UENO Keiji(Material Science Division)｜Saitama University Researcher List

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UENO　Keiji
Material Science Division Professor
Chemistry

Home Page:
http://surface-www.chem.saitama-u.ac.jp/

Researcher information

■ Research Keyword

chemical vapor transport

atomic layer deposition

molecular beam epitaxy

epitaxial growth

layered chalcogenides

transition metal dichalcogenides

layered materials

■ Field Of Study

Manufacturing technology (mechanical, electrical/electronic, chemical engineering), Electronic devices and equipment

Nanotechnology/Materials, Nanostructure chemistry

Nanotechnology/Materials, Nanomaterials

Nanotechnology/Materials, Thin-film surfaces and interfaces

■ Career

Apr. 2019 - Present, Saitama University, Graduate School of Science and Engineering, Professor

Apr. 2007 - Mar. 2019, Saitama University, Graduate School of Science and Engineering, Associate Professor

Oct. 2002 - Mar. 2007, Saitama University, Department of Chemistry, Faculty of Science, Associate Professor

Apr. 1990 - Sep. 2002, The University of Tokyo, Department of Chemistry, Faculty of Science, Research Associate

■ Member History

Apr. 2018 - Present
Society

Apr. 2012 - Mar. 2022
Society

Apr. 2014 - Mar. 2018
Society

Apr. 2010 - Mar. 2014
Society

Performance information

■ Paper

Frequency-modulation atomic force microscopy observation of 1T-TaS2 in the nearly commensurate charge density wave phase　　　　　　　　　　　　　　　
Takahiro Ono; Tomohiro Shigeno; Yuuki Yasui; Masahiro Fukuda; Taisuke Ozaki; Keiji Ueno; Yoshiaki Sugimoto
Applied Physics Letters, Jun. 2025, [Reviewed]
Scientific journal
DOI：https://doi.org/10.1063/5.0273456
DOI ID：10.1063/5.0273456, ORCID：186948295

Dimensionality-Induced Transition from Degenerate to Nondegenerate States in Nb-Doped WSe₂
Kaito Kanahashi; Itsuki Tanaka; Tomonori Nishimura; Kohei Aso; Anh Khoa Augustin Lu; Satoru Morito; Limi Chen; Takafumi Kakeya; Satoshi Watanabe; Yoshifumi Oshima; Yukiko Yamada-Takamura; Keiji Ueno; Amin Azizi; Kosuke Nagashio
ACS Nano, Mar. 2025, [Reviewed]
American Chemical Society (ACS), Scientific journal
DOI：https://doi.org/10.1021/acsnano.4c17660
DOI ID：10.1021/acsnano.4c17660, ISSN：1936-0851, eISSN：1936-086X

Spatial and reconfigurable control of photoluminescence from single-layer MoS2 using a strained VO2-based Fabry–Pérot cavity
Koyo Nakayama; Shota Toida; Takahiko Endo; Mitsuru Inada; Shingo Sato; Hiroshi Tani; Kenji Watanabe; Takashi Taniguchi; Keiji Ueno; Yasumitsu Miyata; Kazunari Matsuda; Mahito Yamamoto
Applied Physics Letters, Volume：125, Number：22, Nov. 2024, [Reviewed]
We investigated the photoluminescence (PL) from single-layer MoS2 on VO2 platelets grown on SiO2, where the insulating and metallic phases can coexist above a bulk transition temperature of 340 K, due to the inhomogeneous strain. We found that the intensity of PL from MoS2 on metallic VO2 is higher than that on the insulating counterpart, resulting in spatially varying PL even at the sub-micrometer scale. In contrast to the intensity, the PL peak energies were observed to be nearly identical on insulating and metallic VO2, indicating that the influences of charge transfer, strain, and dielectric screening on MoS2 are comparable, regardless of the phase state. Thus, the observed difference in PL intensity is due to the difference in refractive indices of insulating and metallic VO2, leading to the phase-dependent Fabry–Pérot interference effect. We performed numerical simulations for the emission from MoS2 supported on the VO2-based Fabry–Pérot interferometer. The calculated emission intensity ratio on insulating and metallic VO2 well reproduces the experimental observations. These results suggest a strategy for controlling PL from two-dimensional semiconductors in a spatial and reconfigurable manner.
AIP Publishing, Scientific journal
DOI：https://doi.org/10.1063/5.0236517
DOI ID：10.1063/5.0236517, ISSN：0003-6951, eISSN：1077-3118

Contact Properties on a Semiconducting MoTe₂ Crystal Using Polymorphic Structures
Tianshun Xie; Mengnan Ke; Peter Krüger; Keiji Ueno; Nobuyuki Aoki
ACS Applied Electronic Materials, Volume：6, Number：9, First page：7026, Last page：7034, Sep. 2024, [Reviewed]
American Chemical Society (ACS), Scientific journal
DOI：https://doi.org/10.1021/acsaelm.4c01369
DOI ID：10.1021/acsaelm.4c01369, ISSN：2637-6113, eISSN：2637-6113

Realization of single MoTe2 crystal in-plane TFET by laser-induced doping technique　　　　　　　　　　　　　　　
Tianshun Xie; Mengnan Ke; Keiji Ueno; Kenji Watanabe; Takashi Taniguchi; Nobuyuki Aoki
Applied Physics Letters, May 2024, [Reviewed]
Scientific journal
DOI：https://doi.org/10.1063/5.0197172
DOI ID：10.1063/5.0197172, ORCID：160223643

Realization of MoTe2 CMOS inverter by contact doping and channel encapsulation　　　　　　　　　　　　　　　
Tianshun Xie; Mengnan Ke; Keiji Ueno; Kenji Watanabe; Takashi Taniguchi; Nobuyuki Aoki
Japanese Journal of Applied Physics, Feb. 2024, [Reviewed]
Scientific journal
DOI：https://doi.org/10.35848/1347-4065/ad16bc
DOI ID：10.35848/1347-4065/ad16bc, ORCID：148977672

Single-Gate MoS₂ Tunnel FET with a Thickness-Modulated Homojunction
Tomohiro Fukui; Tomonori Nishimura; Yasumitsu Miyata; Keiji Ueno; Takashi Taniguchi; Kenji Watanabe; Kosuke Nagashio
ACS Applied Materials & Interfaces, Volume：16, Number：7, First page：8993, Last page：9001, Feb. 2024, [Reviewed]
American Chemical Society (ACS), Scientific journal
DOI：https://doi.org/10.1021/acsami.3c15535
DOI ID：10.1021/acsami.3c15535, ISSN：1944-8244, eISSN：1944-8252

Coherent optical response driven by non-equilibrium electron–phonon dynamics in a layered transition-metal dichalcogenide
Takumi Fukuda; Kotaro Makino; Yuta Saito; Paul Fons; Atsushi Ando; Takuya Mori; Ryo Ishikawa; Keiji Ueno; Jessica Afalla; Muneaki Hase
APL Materials, Volume：12, Number：2, Feb. 2024, [Reviewed]
Layered transition-metal dichalcogenides (TMDs) are model systems to explore ultrafast many-body interactions and various nonlinear optical phenomena. For the application of TMD-based optoelectronic devices capable of ultrafast response, it is essential to understand how characteristic electron–hole and electron–phonon couplings modify ultrafast electronic and optical properties under photoexcitation. Here, we investigate the sub-picosecond optical responses of layered semiconductor 2H–MoTe2 in the presence of an electron–hole (e–h) plasma and a long-lived coherent phonon. Transient reflectivity measurements depending on photon energy reveal that the optical response for short-time delays (< 1ps) was significantly modified by band-gap renormalization and state filling due to the presence of the e–h plasma. Furthermore, octave, sum, and difference phonon frequencies transiently appeared for the early time delays (< 2ps). The emergent multiple phonon frequencies can be described as higher-order optical modulations due to deformation-potential electron–phonon coupling under resonant photoexcitation conditions. This work provides comprehensive insights into fundamental physics and the application of non-equilibrium quasiparticle generations on TMDs under time-periodic phonon driving forces.
AIP Publishing, Scientific journal
DOI：https://doi.org/10.1063/5.0188537
DOI ID：10.1063/5.0188537, eISSN：2166-532X

Silicon–van der Waals heterointegration for CMOS-compatible logic-in-memory design
Mu-Pai Lee; Caifang Gao; Meng-Yu Tsai; Che-Yi Lin; Feng-Shou Yang; Hsin-Ya Sung; Chi Zhang; Wenwu Li; Jun Li; Jianhua Zhang; Kenji Watanabe; Takashi Taniguchi; Keiji Ueno; Kazuhito Tsukagoshi; Ching-Hwa Ho; Junhao Chu; Po-Wen Chiu; Mengjiao Li; Wen-Wei Wu; Yen-Fu Lin
Science Advances, Volume：9, Number：49, Dec. 2023, [Reviewed]
Silicon CMOS-based computing-in-memory encounters design and power challenges, especially in logic-in-memory scenarios requiring nonvolatility and reconfigurability. Here, we report a universal design for nonvolatile reconfigurable devices featuring a 2D/3D heterointegrated configuration. By leveraging the photo-controlled charge trapping/detrapping process and the partially top-gated energy band landscape, the van der Waals heterostacking achieves polarity storage and logic reconfigurable characteristics, respectively. Precise polarity tunability, logic nonvolatility, robustness against high temperature (at 85°C), and near-ideal subthreshold swing (80 mV dec ⁻¹ ) can be done. A comprehensive investigation of dynamic charge fluctuations provides a holistic understanding of the origins of nonvolatile reconfigurability (a trap level of 10 ¹³ cm ⁻² eV ⁻¹ ). Furthermore, we cascade such nonvolatile reconfigurable units into a monolithic circuit layer to demonstrate logic-in-memory computing possibilities, such as high-gain (65 at V_dd = 0.5 V) logic gates. This work provides an innovative 3D heterointegration prototype for future computing-in-memory hardware.
American Association for the Advancement of Science (AAAS), Scientific journal
DOI：https://doi.org/10.1126/sciadv.adk1597
DOI ID：10.1126/sciadv.adk1597, eISSN：2375-2548

Soft x-ray photoelectron momentum microscope for multimodal valence band stereography
Fumihiko Matsui; Kenta Hagiwara; Eiken Nakamura; Takayuki Yano; Hiroyuki Matsuda; Yasuaki Okano; Satoshi Kera; Eri Hashimoto; Shinji Koh; Keiji Ueno; Takahiro Kobayashi; Emi Iwamoto; Kazuyuki Sakamoto; Shin-ichiro Tanaka; Shigemasa SUGA
Review of Scientific Instruments, Volume：94, Number：8, Aug. 2023, [Reviewed]
The photoelectron momentum microscope (PMM) in operation at BL6U, an undulator-based soft x-ray beamline at the UVSOR Synchrotron Facility, offers a new approach for μm-scale momentum-resolved photoelectron spectroscopy (MRPES). A key feature of the PMM is that it can very effectively reduce radiation-induced damage by directly projecting a single photoelectron constant energy contour in reciprocal space with a radius of a few Å−1 or real space with a radius of a few 100 μm onto a two-dimensional detector. This approach was applied to three-dimensional valence band structure E(k) and E(r) measurements (“stereography”) as functions of photon energy (hν), its polarization (e), detection position (r), and temperature (T). In this study, we described some examples of possible measurement techniques using a soft x-ray PMM. We successfully applied this stereography technique to μm-scale MRPES to selectively visualize the single-domain band structure of twinned face-centered-cubic Ir thin films grown on Al2O3(0001) substrates. The photon energy dependence of the photoelectron intensity on the Au(111) surface state was measured in detail within the bulk Fermi surface. By changing the temperature of 1T-TaS2, we clarified the variations in the valence band dispersion associated with chiral charge-density-wave phase transitions. Finally, PMMs for valence band stereography with various electron analyzers were compared, and the advantages of each were discussed.
{AIP} Publishing, English, Scientific journal
DOI：https://doi.org/10.1063/5.0154156
DOI ID：10.1063/5.0154156, ISSN：0034-6748, eISSN：1089-7623, ORCID：140830833

Photoinduced Structural Dynamics of 2H-MoTe₂ Under Extremely High-Density Excitation Conditions
Takumi Fukuda; Uta Ozaki; Samuel Jeong; Yusuke Arashida; Kaito En-ya; Shoji Yoshida; Paul J. Fons; Jun-ichi Fujita; Keiji Ueno; Muneaki Hase; Masaki Hada
The Journal of Physical Chemistry C, Jul. 2023, [Reviewed]
American Chemical Society (ACS), Scientific journal
DOI：https://doi.org/10.1021/acs.jpcc.3c02838
DOI ID：10.1021/acs.jpcc.3c02838, ISSN：1932-7447, eISSN：1932-7455

Ultrafast melting of charge-density wave fluctuations at room temperature in 1T-TiSe2 monitored under non-equilibrium conditions
Yu Mizukoshi; Takumi Fukuda; Yuta Komori; Ryo Ishikawa; Keiji Ueno; Muneaki Hase
Applied Physics Letters, Volume：122, Number：24, Jun. 2023, [Reviewed]
We investigate the ultrafast lattice dynamics in 1T-TiSe2 using femtosecond reflection pump–probe and pump–pump–probe techniques at room temperature. The time-domain signals and Fourier-transformed spectra show the A1g phonon mode at 5.9 THz. Moreover, we observe an additional mode at ≈ 3 THz, corresponding to the charge-density wave (CDW) amplitude mode (AM), which is generally visible below Tc≈200 K. We argue that the emergence of the CDW amplitude mode at room temperature can be a consequence of fluctuations of order parameters based on the additional experiment using the pump–pump–probe technique, which exhibited suppression of the AM signal within the ultrafast timescale of ∼0.5 ps.
AIP Publishing, Scientific journal
DOI：https://doi.org/10.1063/5.0153161
DOI ID：10.1063/5.0153161, ISSN：0003-6951, eISSN：1077-3118

Terahertz emission from transient currents and coherent phonons in layered MoSe2 and WSe2
Jessica Afalla; Joselito Muldera; Semmi Takamizawa; Takumi Fukuda; Keiji Ueno; Masahiko Tani; Muneaki Hase
Journal of Applied Physics, Volume：133, Number：16, Apr. 2023, [Reviewed]
Terahertz (THz) time-domain emission spectroscopy was performed on layered 2H-MoSe 2 and 2H-WSe 2. The THz emission shows an initial cycle attributed to surge currents and is followed by oscillations attributed to coherent interlayer phonon modes. To obtain the frequencies of the interlayer vibrations, an analysis of the THz emission waveforms was performed, separating the two contributions to the total waveform. Results of the fitting show several vibrational modes in the range of 5.87–32.75 cm − 1 for the samples, attributed to infrared-active interlayer shear and breathing modes. This study demonstrates that THz emission spectroscopy provides a means of observing these low-frequency vibrational modes in layered materials.
AIP Publishing, Scientific journal
DOI：https://doi.org/10.1063/5.0146489
DOI ID：10.1063/5.0146489, ISSN：0021-8979, eISSN：1089-7550

Carrier Transport Properties in Few-Layer WS_0.3Se_1.7/(WO_x)WS_0.3Se_1.7 Lateral p⁺–n Junctions Using a Metal–Oxide–Semiconductor Field-Effect Transistor (MOSFET) Structure
Abdul Kuddus; Kojun Yokoyama; Wenbo Fan; Keiji Ueno; Hajime Shirai
ACS Applied Electronic Materials, Volume：23, Number：3, First page：1546, Last page：1557, Mar. 2023, [Reviewed]
American Chemical Society (ACS), Scientific journal
DOI：https://doi.org/10.1021/acsaelm.2c01598
DOI ID：10.1021/acsaelm.2c01598, ISSN：2637-6113, eISSN：2637-6113

Multilayer In-Plane Heterostructures Based on Transition Metal Dichalcogenides for Advanced Electronics　　　　　　　　　　　　　　　
Hiroto Ogura; Seiya Kawasaki; Zheng Liu; Takahiko Endo; Mina Maruyama; Yanlin Gao; Yusuke Nakanishi; Hong En Lim; Kazuhiro Yanagi; Toshifumi Irisawa; Keiji Ueno; Susumu Okada; Kosuke Nagashio; Yasumitsu Miyata
ACS Nano, Volume：17, Number：7, First page：6545, Last page：6554, Feb. 2023, [Reviewed]
Scientific journal
DOI：https://doi.org/10.1021/acsnano.2c11927
Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85149104150&origin=inward
Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85149104150&origin=inward
DOI ID：10.1021/acsnano.2c11927, ISSN：1936-0851, eISSN：1936-086X, ORCID：129773033, PubMed ID：36847351, SCOPUS ID：85149104150

Enhanced contact properties of MoTe₂-FET via laser-induced heavy doping
Tianshun Xie; Kazuki Fukuda; Mengnan Ke; Peter Krüger; Keiji Ueno; Gil-Ho Kim; Nobuyuki Aoki
Japanese Journal of Applied Physics, Volume：62, Number：SC, First page：SC1010, Last page：SC1010, Dec. 2022, [Reviewed]
Abstract

The doping technique is vital for applying two-dimensional (2D) materials such as transition metal dichalcogenide (TMDC)-based field effect transistors (FETs), which can control the channel polarity and improve the performance. However, as conventional doping techniques for silicon-based FET are not suitable for 2D materials, the realization of heavy doping of TMDC materials is challenging, especially for n-type heavy doping. This study reports a simple, regioselective, controllable, and chemically stable heavy doping method for 2H-MoTe₂ crystal via high-density laser irradiation. The polarity of the doping can be controlled by changing the irradiation environment. For the MoTe₂-nFET, good performance with enhanced contact properties was obtained using the contact doping method via laser irradiation in a vacuum environment.
IOP Publishing, Scientific journal
DOI：https://doi.org/10.35848/1347-4065/aca67e
DOI ID：10.35848/1347-4065/aca67e, ISSN：0021-4922, eISSN：1347-4065

Is the Bandgap of Bulk PdSe2Located Truly in the Far-Infrared Region? Determination by Fourier-Transform Photocurrent Spectroscopy
Wataru Nishiyama; Tomonori Nishimura; Masao Nishioka; Keiji Ueno; Satoshi Iwamoto; Kosuke Nagashio
Advanced Photonics Research, Volume：3, Number：11, First page：2200231, Last page：2200231, Nov. 2022, [Reviewed]
Wiley, Scientific journal
DOI：https://doi.org/10.1002/adpr.202200231
DOI ID：10.1002/adpr.202200231, ISSN：2699-9293, eISSN：2699-9293

Diffused beam energy to dope van der waals electronics and boost their contact barrier lowering　　　　　　　　　　　　　　　
Che-Yi Lin; Mu-Pai Lee; Yuan-Ming Chang; Yi-Tang Tseng; Feng-Shou Yang; Mengjiao Li; Jiann-Yeu Chen; Ciao-Fen Chen; Meng-Yu Tsai; Yi-Chun Lin; Keiji Ueno; Mahito Yamamoto; Shun-Tsung Lo; Chen-Hsin Lien; Po-Wen Chiu; Kazuhito Tsukagoshi; Wen-Wei Wu; Yen-Fu Lin
ACS applied materials & interfaces, Aug. 2022, [Reviewed]
American chemical society ({ACS}), English, Scientific journal
DOI：https://doi.org/10.1021/acsami.2c07679
DOI ID：10.1021/acsami.2c07679, ISSN：1944-8244, ORCID：118159145

Photo‐Induced Tellurium Segregation in MoTe 2
Takumi Fukuda; Ryota Kaburauchi; Yuta Saito; Kotaro Makino; Paul Fons; Keiji Ueno; Muneaki Hase
physica status solidi (RRL) – Rapid Research Letters, Volume：16, Number：9, First page：2100633, Last page：2100633, Jun. 2022, [Reviewed]
Wiley, Scientific journal
DOI：https://doi.org/10.1002/pssr.202100633
DOI ID：10.1002/pssr.202100633, ISSN：1862-6254, eISSN：1862-6270, ORCID：114313321

Mist chemical vapor deposition of Al1−xTixOy thin films and their application to a high dielectric material　　　　　　　　　　　　　　　
Arifuzzaman Rajib; Abdul Kuddus; Kojun Yokoyama; Tomohiro Shida; Keiji Ueno; Hajime Shirai
Journal of Applied Physics, Volume：131, Number：10, First page：105301, Last page：105301, Mar. 2022, [Reviewed]
{AIP} Publishing, Scientific journal
DOI：https://doi.org/10.1063/5.0073719
DOI ID：10.1063/5.0073719, ORCID：109527683

Mist chemical vapor deposition of crystalline MoS2 atomic layer films using sequential mist supply mode and its application in field-effect transistors　　　　　　　　　　　　　　　
Abdul Kuddus; Arifuzzaman Rajib; Kojun Yokoyama; Tomohiro Shida; Keiji Ueno; Hajime Shirai
Nanotechnology, Volume：33, Number：4, Jan. 2022, [Reviewed]
{IOP} Publishing, Scientific journal
DOI：https://doi.org/10.1088/1361-6528/ac30f4
Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85119168347&origin=inward
DOI ID：10.1088/1361-6528/ac30f4, ISSN：0957-4484, eISSN：1361-6528, ORCID：101720561, PubMed ID：34666322, SCOPUS ID：85119168347

Intrinsic Electronic Transport Properties and Carrier Densities in PtS2 and SnSe2: Exploration of n(+)-Source for 2D Tunnel FETs　　　　　　　　　　　　　　　
Yuichiro Sato; Tomonori Nishimura; Dong Duanfei; Keiji Ueno; Keisuke Shinokita; Kazunari Matsuda; Kosuke Nagashio
ADVANCED ELECTRONIC MATERIALS, Volume：7, Number：12, Dec. 2021, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1002/aelm.202100292
DOI ID：10.1002/aelm.202100292, ISSN：2199-160X, Web of Science ID：WOS:000681339800001

Improved Efficiency of Perovskite Solar Cells by adding fluorophenyl phosphine　　　　　　　　　　　　　　　
Ishikawa Ryo; Ueno keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2021.2, First page：2312, Last page：2312, Aug. 2021
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2021.2.0_2312
DOI ID：10.11470/jsapmeeting.2021.2.0_2312, eISSN：2436-7613

State-of-the-Art of Solution-Processed Crystalline Silicon/Organic Heterojunction Solar Cells: Challenges and Future
Jaker Hossain; A. T. M. Saiful Islam; Koji Kasahara; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
Challenges and Advances in Computational Chemistry and Physics, First page：33, Last page：56, May 2021, [Reviewed]
Springer International Publishing, In book
DOI：https://doi.org/10.1007/978-3-030-69445-6_2
DOI ID：10.1007/978-3-030-69445-6_2, ISSN：2542-4491, eISSN：2542-4483

Material and Device Structure Designs for 2D Memory Devices Based on the Floating Gate Voltage Trajectory　　　　　　　　　　　　　　　
Taro Sasaki; Keiji Ueno; Takashi Taniguchi; Kenji Watanabe; Tomonori Nishimura; Kosuke Nagashio
ACS NANO, Volume：15, Number：4, First page：6658, Last page：6668, Apr. 2021
English, Scientific journal
DOI：https://doi.org/10.1021/acsnano.0c10005
DOI ID：10.1021/acsnano.0c10005, ISSN：1936-0851, eISSN：1936-086X, Web of Science ID：WOS:000645436800061

Improvement of FA_0.9Cs_0.1Pb(I_0.65Br_0.35)₃ thin film for the fabrication of tandem solar cells　　　　　　　　　　　　　　　
Shimomura Kazushi; Ishikawa Ryo; Ueno Keiji; Hajime Shirai
JSAP Annual Meetings Extended Abstracts, Volume：2021.1, First page：2118, Last page：2118, Feb. 2021
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2021.1.0_2118
DOI ID：10.11470/jsapmeeting.2021.1.0_2118, eISSN：2436-7613

AlOxThin Films Synthesized by Mist Chemical Vapor Deposition, Monitored by a Fast-Scanning Mobility Particle Analyzer, and Applied as a Gate Insulating Layer in the Field-Effect Transistors　　　　　　　　　　　　　　　
Arifuzzaman Rajib; Abdul Kuddus; Tomohiro Shida; Keiji Ueno; Hajime Shirai
ACS Applied Electronic Materials, Volume：3, Number：2, First page：658, Last page：667, Feb. 2021
Scientific journal
DOI：https://doi.org/10.1021/acsaelm.0c00758
Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85099954273&origin=inward
Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85099954273&origin=inward
DOI ID：10.1021/acsaelm.0c00758, eISSN：2637-6113, SCOPUS ID：85099954273

Enhanced Exciton-Exciton Collisions in an Ultraflat Monolayer MoSe2 Prepared through Deterministic Flattening.　　　　　　　　　　　　　　　
Takato Hotta; Akihiko Ueda; Shohei Higuchi; Mitsuhiro Okada; Tetsuo Shimizu; Toshitaka Kubo; Keiji Ueno; Takashi Taniguchi; Kenji Watanabe; Ryo Kitaura
ACS nano, Dec. 2020, ［International magazine］
Squeezing bubbles and impurities out of interlayer spaces by applying force through a few-layer graphene capping layer leads to van der Waals heterostructures with the ultraflat structure free from random electrostatic potential arising from charged impurities. Without the graphene capping layer, a squeezing process with an AFM tip induces applied-force-dependent charges of Δn ∼ 2 × 1012 cm-2 μN-1, resulting in the significant intensity of trions in photoluminescence spectra of MoSe2 at low temperature. We found that a hBN/MoSe2/hBN prepared with the "graphene-capping-assisted AFM nano-squeezing method" shows a strong excitonic emission with negligible trion peak, and the residual line width of the exciton peak is only 2.2 meV, which is comparable to the homogeneous limit. Furthermore, in this high-quality sample, we found that the formation of biexciton occurs even at extremely low excitation power (Φph ∼ 2.3 × 1019 cm-2 s-1) due to the enhanced collisions between excitons.
English
DOI：https://doi.org/10.1021/acsnano.0c08642
DOI ID：10.1021/acsnano.0c08642, arXiv ID：arXiv:2006.02640, PubMed ID：33356145

All 2D Heterostructure Tunnel Field-Effect Transistors: Impact of Band Alignment and Heterointerface Quality
Keigo Nakamura; Naoka Nagamura; Keiji Ueno; Takashi Taniguchi; Kenji Watanabe; Kosuke Nagashio
ACS Applied Materials & Interfaces, Volume：12, Number：46, First page：51598, Last page：51606, Nov. 2020
American Chemical Society (ACS), Scientific journal
DOI：https://doi.org/10.1021/acsami.0c13233
DOI ID：10.1021/acsami.0c13233, ISSN：1944-8244, eISSN：1944-8252

Flat bands in twisted bilayer transition metal dichalcogenides　　　　　　　　　　　　　　　
Zhiming Zhang; Yimeng Wang; Kenji Watanabe; Takashi Taniguchi; Keiji Ueno; Emanuel Tutuc; Brian J. LeRoy
Nature Physics, Volume：16, Number：11, First page：1093, Last page：1096, Nov. 2020
Nature Research, English, Scientific journal
DOI：https://doi.org/10.1038/s41567-020-0958-x
DOI ID：10.1038/s41567-020-0958-x, ISSN：1745-2481, SCOPUS ID：85087652297

Understanding the Memory Window Overestimation of 2D Materials Based Floating Gate Type Memory Devices by Measuring Floating Gate Voltage　　　　　　　　　　　　　　　
Taro Sasaki; Keiji Ueno; Takashi Taniguchi; Kenji Watanabe; Tomonori Nishimura; Kosuke Nagashio
SMALL, Volume：16, Number：47, Nov. 2020
English, Scientific journal
DOI：https://doi.org/10.1002/smll.202004907
DOI ID：10.1002/smll.202004907, ISSN：1613-6810, eISSN：1613-6829, Web of Science ID：WOS:000583797900001

Exciton diffusion in hBN-encapsulated monolayer MoSe2　　　　　　　　　　　　　　　
Takato Hotta; Shohei Higuchi; Akihiro Ueda; Keisuke Shinokita; Yuhei Miyauchi; Kazunari Matsuda; Keiji Ueno; Takashi Taniguchi; Kenji Watanabe; Ryo Kitaura
PHYSICAL REVIEW B, Volume：102, Number：11, Sep. 2020
English, Scientific journal
DOI：https://doi.org/10.1103/PhysRevB.102.115424
DOI ID：10.1103/PhysRevB.102.115424, ISSN：2469-9950, eISSN：2469-9969, Web of Science ID：WOS:000571391100006

Facile and reversible carrier-type manipulation of layered MoTe2 toward long-term stable electronics
Mengjiao Li; Che-Yi Lin; Yuan-Ming Chang; Shih-Hsien Yang; Mu-Pai Lee; Ciao-Fen Chen; Ko-Chun Lee; Feng-Shou Yang; Yi Chou; Yi-Chun Lin; Keiji Ueno; Yumeng Shi; Yi-Chia Chou; Kazuhito Tsukagoshi; Yen-Fu Lin
ACS Applied Materials & Interfaces, Aug. 2020
American Chemical Society (ACS), Scientific journal
DOI：https://doi.org/10.1021/acsami.0c09922
DOI ID：10.1021/acsami.0c09922, ISSN：1944-8244, eISSN：1944-8252

Effect of thermally annealed atomic-layer-deposited AlOx/chemical tunnel oxide stack layer at the PEDOT:PSS/n-type Si interface to improve its junction quality　　　　　　　　　　　　　　　
Md Enamul Karim; Yuki Nasuno; Abdul Kuddus; Tomofumi Ukai; Shunji Kurosu; Masahide Tokuda; Yasuhiko Fujii; Tatsuro Hanajiri; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
JOURNAL OF APPLIED PHYSICS, Volume：128, Number：4, Jul. 2020
English, Scientific journal
DOI：https://doi.org/10.1063/5.0007918
DOI ID：10.1063/5.0007918, ISSN：0021-8979, eISSN：1089-7550, Web of Science ID：WOS:000556325800003

Investigation of laser-induced-metal phase of MoTe2 and its contact property via scanning gate microscopy　　　　　　　　　　　　　　　
Kohei Sakanashi; Hidemitsu Ouchi; Kota Kamiya; Peter Krüger; Katsuhiko Miyamoto; Takashige Omatsu; Keiji Ueno; Kenji Watanabe; Takashi Taniguchi; Jonathan P. Bird; Nobuyuki Aoki
Nanotechnology, Volume：31, Number：20, First page：205205, May 2020, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1088/1361-6528/ab71b8
Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85082307375&origin=inward
Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85082307375&origin=inward
DOI ID：10.1088/1361-6528/ab71b8, ISSN：0957-4484, eISSN：1361-6528, SCOPUS ID：85082307375

Synthesis of AlOx thin films by atmospheric-pressure mist chemical vapor deposition for surface passivation and electrical insulator layers
Arifuzzaman Rajib; Karim Md Enamul; Shunji Kurosu; Tomofumi Ukai; Masahide Tokuda; Yasuhiko Fujii; Tatsuro Hanajiri; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
Journal of Vacuum Science & Technology A, Volume：38, Number：3, First page：033413, Last page：033413, May 2020
American Vacuum Society, Scientific journal
DOI：https://doi.org/10.1116/1.5143273
DOI ID：10.1116/1.5143273, ISSN：0734-2101, eISSN：1520-8559

Ultrafast dynamics of the low frequency shear phonon in 1T′- MoTe 2
Takumi Fukuda; Kotaro Makino; Yuta Saito; Paul Fons; Alexander V. Kolobov; Keiji Ueno; Muneaki Hase
Applied Physics Letters, Volume：116, Number：9, First page：093103, Last page：093103, Mar. 2020
AIP Publishing, Scientific journal
DOI：https://doi.org/10.1063/1.5143485
DOI ID：10.1063/1.5143485, ISSN：0003-6951, eISSN：1077-3118

Improved efficiency of methylammonium-free perovskite thin film solar cells by fluorinated ammonium iodide treatment　　　　　　　　　　　　　　　
Ryo Ishikawa; Keiji Ueno; Hajime Shirai
Organic Electronics, Volume：78, First page：105596, Last page：105596, Mar. 2020
Elsevier BV, Scientific journal
DOI：https://doi.org/10.1016/j.orgel.2019.105596
DOI ID：10.1016/j.orgel.2019.105596, ISSN：1566-1199

Investigation of Surface passivation effects by Fluorinated Polymer in FA_0.8Cs_0.2PbI₃thin film and photovoltaic cells　　　　　　　　　　　　　　　
Moriya Yuma; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2020.1, First page：2414, Last page：2414, Feb. 2020
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2020.1.0_2414
DOI ID：10.11470/jsapmeeting.2020.1.0_2414, eISSN：2436-7613

Low-temperature growth of crystalline tungsten disulfide thin films by using organic liquid precursors　　　　　　　　　　　　　　　
Yukihiro Ikeda; Keiji Ueno
Japanese Journal of Applied Physics, Volume：59, Feb. 2020
Institute of Physics Publishing, English, Scientific journal
DOI：https://doi.org/10.7567/1347-4065/ab489a
DOI ID：10.7567/1347-4065/ab489a, ISSN：1347-4065, SCOPUS ID：85081950694

Self-assembled Fluorinated Polymer Passivation Layer for Efficient Perovskite Thin-film Solar Cells
Yuma Moriya; Ryo Ishikawa; Shuhei Akiyama; Keiji Ueno; Hajime Shirai
Chemistry Letters, Volume：49, Number：1, First page：87, Last page：90, Jan. 2020
The Chemical Society of Japan, Scientific journal
DOI：https://doi.org/10.1246/cl.190692
DOI ID：10.1246/cl.190692, ISSN：0366-7022, eISSN：1348-0715

Oxygen-Sensitive Layered MoTe2 Channels for Environmental Detection　　　　　　　　　　　　　　　
Shih-Hsien Yang; Che-Yi Lin; Yuan-Ming Chang; Mengjiao Li; Ko-Chun Lee; Ciao-Fen Chen; Feng-Shou Yang; Chen-Hsin Lien; Keiji Ueno; Kenji Watanabe; Takashi Taniguchi; Kazuhito Tsukagoshi; Yen-Fu Lin
ACS APPLIED MATERIALS & INTERFACES, Volume：11, Number：50, First page：47047, Last page：47053, Dec. 2019
English, Scientific journal
DOI：https://doi.org/10.1021/acsami.9b15036
DOI ID：10.1021/acsami.9b15036, ISSN：1944-8244, eISSN：1944-8252, Web of Science ID：WOS:000503918300069

Selective oxidation of the surface layer of bilayer WSe2 by laser heating
Hiroki Shioya; Kazuhito Tsukagoshi; Keiji Ueno; Akira Oiwa
Japanese Journal of Applied Physics, Volume：58, Number：12, First page：120903, Last page：120903, Dec. 2019, [Reviewed]
IOP Publishing, Scientific journal
DOI：https://doi.org/10.7567/1347-4065/ab50da
DOI ID：10.7567/1347-4065/ab50da, ISSN：0021-4922, eISSN：1347-4065

Selective oxidation of the surface layer of bilayer WSe2 by laser heating
Shioya, Hiroki; TSUKAGOSHI, Kazuhito; Ueno, Keiji; Oiwa, Akira
Japanese Journal of Applied Physics, Dec. 2019, [Reviewed]
Scientific journal
DOI：https://doi.org/10.7567/1347-4065/ab50da
DOI ID：10.7567/1347-4065/ab50da, ISSN：1347-4065, ORCID：64386641

Role of the solvent in large crystal grain growth of inorganic-organic halide FA_0.8Cs_0.2PbI_xBr_3 −_x perovskite thin films monitored by ellipsometry
Koki Kawamura; Ryo Ishikawa; Yoko Wasai; Nataliya Nabatova-Gabain; Shun-ji Kurosu; Tomofumi Ukai; Masahide Tokuda; Yasuhiko Fujii; Tatsuro Hanajiri; Keiji Ueno; Hajime Shirai
Journal of Vacuum Science & Technology B, Volume：37, Number：6, First page：062401, Last page：062401, Nov. 2019
American Vacuum Society, Scientific journal
DOI：https://doi.org/10.1116/1.5123399
DOI ID：10.1116/1.5123399, ISSN：2166-2746, eISSN：2166-2754

Barrier Formation at the Contacts of Vanadium Dioxide and Transition-Metal Dichalcogenides
Mahito Yamamoto; Ryo Nouchi; Teruo Kanki; Shu Nakaharai; Azusa N. Hattori; Kenji Watanabe; Takashi Taniguchi; Yutaka Wakayama; Keiji Ueno; Hidekazu Tanaka
ACS Applied Materials & Interfaces, Volume：11, Number：40, First page：36871, Last page：36879, Oct. 2019
American Chemical Society (ACS), Scientific journal
DOI：https://doi.org/10.1021/acsami.9b13763
DOI ID：10.1021/acsami.9b13763, ISSN：1944-8244, eISSN：1944-8252

Role of TSC additive in the grain growth of perovskite phase　　　　　　　　　　　　　　　
Kawamura Koki; Wasai Yoko; Nabatova-Gabain Nataliya; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2019.2, First page：2733, Last page：2733, Sep. 2019
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2019.2.0_2733
DOI ID：10.11470/jsapmeeting.2019.2.0_2733, eISSN：2436-7613

Fabrication and characterization of Perovskite photovoltaic cells with low temperature processed Carbon Electrode　　　　　　　　　　　　　　　
Moriya Yuma; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2019.2, First page：2703, Last page：2703, Sep. 2019
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2019.2.0_2703
DOI ID：10.11470/jsapmeeting.2019.2.0_2703, eISSN：2436-7613

Fabrication and characterization of highly oriented and durable two-dimensional (4F-PEA)₂PbI₄ incorporating perovskite thin films　　　　　　　　　　　　　　　
Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2019.2, First page：2704, Last page：2704, Sep. 2019
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2019.2.0_2704
DOI ID：10.11470/jsapmeeting.2019.2.0_2704, eISSN：2436-7613

Highly crystalline large-grained perovskite films using two additives without an antisolvent for high-efficiency solar cells　　　　　　　　　　　　　　　
Ryo Ishikawa; Keiji Ueno; Hajime Shirai
Thin Solid Films, Volume：679, First page：27, Last page：34, Jun. 2019
Elsevier BV, Scientific journal
DOI：https://doi.org/10.1016/j.tsf.2019.03.030
DOI ID：10.1016/j.tsf.2019.03.030, ISSN：0040-6090

Fabrication and characterization of Fluorinated polymer combined Perovskite photovoltaic cells.　　　　　　　　　　　　　　　
Moriya Yuma; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2019.1, First page：2414, Last page：2414, Feb. 2019
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2019.1.0_2414
DOI ID：10.11470/jsapmeeting.2019.1.0_2414, eISSN：2436-7613

Improved Efficiency of Perovskite Solar Cells by fluorinated amine treatment　　　　　　　　　　　　　　　
Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2019.1, First page：2413, Last page：2413, Feb. 2019
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2019.1.0_2413
DOI ID：10.11470/jsapmeeting.2019.1.0_2413, eISSN：2436-7613

Exciton Diffusion in hBN-encapsulated Monolayer MoSe2　　　　　　　　　　　　　　　
Takato Hotta; Syohei Higuchi; Yosuke Uchiyama; Keiji Ueno; Kenji Watanabe; Takashi Taniguchi; Hisanori Shinohara; Ryo Kitaura
2019 COMPOUND SEMICONDUCTOR WEEK (CSW), 2019
English, International conference proceedings
Web of Science ID：WOS:000539485600130

Site-dependence of relationships between photoluminescence and applied electric field in monolayer and bilayer molybdenum disulfide　　　　　　　　　　　　　　　
Junji Nozaki; Hiroyuki Nishidome; Mina Maruyama; Susumu Okada; Satoshi Kusaba; Koichiro Tanaka; Keiji Ueno; Yohei Yomogida; Kazuhiro Yanagi
Japanese Journal of Applied Physics, Volume：58, Number：1, Jan. 2019
Institute of Physics Publishing, English, Scientific journal
DOI：https://doi.org/10.7567/1347-4065/aaead2
DOI ID：10.7567/1347-4065/aaead2, ISSN：1347-4065, SCOPUS ID：85059871335

Gate-Tunable Thermal Metal-Insulator Transition in VO2 Monolithically Integrated into a WSe2 Field-Effect Transistor　　　　　　　　　　　　　　　
Mahito Yamamoto; Ryo Nouchi; Teruo Kanki; Azusa N Hattori; Kenji Watanabe; Takashi Taniguchi; Keiji Ueno; Hidekazu Tanaka
ACS applied materials & interfaces, Volume：11, Number：3, First page：3224, Last page：3230, Jan. 2019, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1021/acsami.8b18745
DOI ID：10.1021/acsami.8b18745, ISSN：1944-8244, eISSN：1944-8252, Web of Science ID：WOS:000457067300076

Self-passivated ultra-thin SnS layers via mechanical exfoliation and post-oxidation　　　　　　　　　　　　　　　
Higashitarumizu Naoki; Kawamoto Hayami; Nakamura Masaru; Shimamura Kiyoshi; Ohashi Naoki; Ueno Keiji; Nagashio Kosuke
NANOSCALE, Volume：10, Number：47, First page：22474, Last page：22483, Dec. 2018, [Reviewed]
DOI：https://doi.org/10.1039/c8nr06390g
DOI ID：10.1039/c8nr06390g, ISSN：2040-3364, PubMed ID：30480284, Web of Science ID：WOS:000452490800036

Fabrication and characterization of K_x(FA_0.8Cs_0.2)_1-xPbI₃thin films by one step method using additive　　　　　　　　　　　　　　　
Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2018.2, First page：2552, Last page：2552, Sep. 2018
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2018.2.0_2552
DOI ID：10.11470/jsapmeeting.2018.2.0_2552, eISSN：2436-7613

Fabrication and Spin Transport Properties of van der Waals Heterostructures based on Ferromagnetic Transition Metal Dichalcogenides　　　　　　　　　　　　　　　
Moriya Rai; Yamasaki Yuji; Arai Miho; Masubuchi Satoru; Pyon Sunseng; Tamegai Tsuyoshi; Ueno Keiji; Machida Tomoki
JSAP Annual Meetings Extended Abstracts, Volume：2018.2, First page：137, Last page：137, Sep. 2018
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2018.2.0_137
DOI ID：10.11470/jsapmeeting.2018.2.0_137, eISSN：2436-7613

Fabrication of [CH(NH₂)₂]_0.8Cs_0.2PbI₃ Perovskite Thin Films for n-i-p Planar-structure Solar Cells by a One-step Method Using 1-Cyclohexyl-2-pyrrolidone as an Additive
Ryo Ishikawa; Keiji Ueno; Hajime Shirai
Chemistry Letters, Volume：47, Number：7, First page：905, Last page：908, Jul. 2018
The Chemical Society of Japan, Scientific journal
DOI：https://doi.org/10.1246/cl.180216
DOI ID：10.1246/cl.180216, ISSN：0366-7022, eISSN：1348-0715

2D Tunnel Field Effect Transistors (FETs) with a Stable Charge-Transfer-Type p(+)-WSe2 Source　　　　　　　　　　　　　　　
He Junyang; Fang Nan; Nakamura Keigo; Ueno Keiji; Taniguchi Takashi; Watanabe Kenji; Nagashio Kosuke
ADVANCED ELECTRONIC MATERIALS, Volume：4, Number：7, Jul. 2018, [Reviewed]
DOI：https://doi.org/10.1002/aelm.201800207
DOI ID：10.1002/aelm.201800207, ISSN：2199-160X, Web of Science ID：WOS:000437828700021

Ultrathin Bismuth Film on 1T-TaS2: Structural Transition and Charge-Density-Wave Proximity Effect　　　　　　　　　　　　　　　
Keiko Yamada; Seigo Souma; Kunihiko Yamauchi; Natsumi Shimamura; Katsuaki Sugawara; Chi Xuan Trang; Tamio Oguchi; Keiji Ueno; Takashi Takahashi; Takafumi Sato
Nano Letters, Volume：18, Number：5, First page：3235, Last page：3240, May 2018, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1021/acs.nanolett.8b01003
DOI ID：10.1021/acs.nanolett.8b01003, ISSN：1530-6992, SCOPUS ID：85046664908, Web of Science ID：WOS:000432093200070

Anisotropic band splitting in monolayer NbSe2: implications for superconductivity and charge density wave　　　　　　　　　　　　　　　
Nakata Yuki; Sugawara Katsuaki; Ichinokura Satoru; Okada Yoshinori; Hitosugi Taro; Koretsune Takashi; Ueno Keiji; Hasegawa Shuji; Takahashi Takashi; Sato Takafumi
NPJ 2D MATERIALS AND APPLICATIONS, Volume：2, May 2018, [Reviewed]
DOI：https://doi.org/10.1038/s41699-018-0057-3
DOI ID：10.1038/s41699-018-0057-3, ISSN：2397-7132, Web of Science ID：WOS:000441131600001

Pronounced photogating effect in atomically thin WSe2 with a self-limiting surface oxide layer
Mahito Yamamoto; Keiji Ueno; Kazuhito Tsukagoshi
Applied Physics Letters, Volume：112, Number：18, Apr. 2018, [Reviewed]
American Institute of Physics Inc., English, Scientific journal
DOI：https://doi.org/10.1063/1.5030525
DOI ID：10.1063/1.5030525, ISSN：0003-6951, ORCID：44180688, SCOPUS ID：85046538865

Reversible and Precisely Controllable p/n-Type Doping of MoTe2 Transistors through Electrothermal Doping　　　　　　　　　　　　　　　
Yuan-Ming Chang; Shih-Hsien Yang; Che-Yi Lin; Chang-Hung Chen; Chen-Hsin Lien; Wen-Bin Jian; Keiji Ueno; Yuen-Wuu Suen; Kazuhito Tsukagoshi; Yen-Fu Lin
Advanced Materials, Volume：30, Number：13, Mar. 2018, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1002/adma.201706995
DOI ID：10.1002/adma.201706995, ISSN：1521-4095, SCOPUS ID：85041844399, Web of Science ID：WOS:000428793600028

Fabrication and characterization of Fluorinated polymer combined FA_0.8Cs_0.2PbI₃ thin films　　　　　　　　　　　　　　　
Akiyama Shuhei; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2018.1, First page：2786, Last page：2786, Mar. 2018
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2018.1.0_2786
DOI ID：10.11470/jsapmeeting.2018.1.0_2786, eISSN：2436-7613

Perovskite photovoltaic cells with bilayer electron-transporting layers of titanium oxide and tin oxide　　　　　　　　　　　　　　　
Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2018.1, First page：2752, Last page：2752, Mar. 2018
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2018.1.0_2752
DOI ID：10.11470/jsapmeeting.2018.1.0_2752, eISSN：2436-7613

Optical anisotropy and compositional ratio of conductive polymer PEDOT: PSS and their effect on photovoltaic performance of crystalline silicon/organic heterojunction solar cells　　　　　　　　　　　　　　　
Hajime Shirai; Qiming Liu; Tatsuya Ohki; Ryo Ishikawa; Keiji Ueno
Advances in Silicon Solar Cells, First page：137, Last page：159, Jan. 2018, [Reviewed]
Springer International Publishing, English, In book
DOI：https://doi.org/10.1007/978-3-319-69703-1_5
DOI ID：10.1007/978-3-319-69703-1_5, SCOPUS ID：85045552655

Exciton Diffusion in a hBN-encapsulated Monolayer Transition Metal Dichalcogenide　　　　　　　　　　　　　　　
Takato Hotta; Shohei Higuchi; Yosuke Uchiyama; Keiji Ueno; Kenji Watanabe; Takashi Taniguchi; Hisanori Shinohara; Ryo Kitaura
Optics InfoBase Conference Papers, Volume：Part F125-JSAP 2018, 2018
International conference proceedings
Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85065880514&origin=inward
Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85065880514&origin=inward
SCOPUS ID：85065880514

Fabrication and Surface Engineering of Two-Dimensional SnS Toward Piezoelectric Nanogenerator Application　　　　　　　　　　　　　　　
Higashitarumizu Naoki; Kawamoto Hayami; Ueno Keiji; Nagashio Kosuke
MRS ADVANCES, Volume：3, Number：45-46, First page：2809, Last page：2814, 2018, [Reviewed]
DOI：https://doi.org/10.1557/adv.2018.404
DOI ID：10.1557/adv.2018.404, ISSN：2059-8521, Web of Science ID：WOS:000445086800009

Exfoliation and van der Waals heterostructure assembly of intercalated ferromagnet Cr1/3TaS2　　　　　　　　　　　　　　　
Yuji Yamasaki; Rai Moriya; Miho Arai; Satoru Masubuchi; Sunseng Pyon; Tsuyoshi Tamegai; Keiji Ueno; Tomoki Machida
2D MATERIALS, Volume：4, Number：4, Dec. 2017, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1088/2053-1583/aa8a2b
DOI ID：10.1088/2053-1583/aa8a2b, ISSN：2053-1583, Web of Science ID：WOS:000411520500001

Fine structure of CsPbI₂ dependent Cs_0.2FA_0.8PbI_xBr_3-xperovskite by two-step reaction　　　　　　　　　　　　　　　
Miura Takuya; Takahashi Kotaro; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2017.2, First page：2576, Last page：2576, Aug. 2017
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2017.2.0_2576
DOI ID：10.11470/jsapmeeting.2017.2.0_2576, eISSN：2436-7613

Fabrication and characterization of FA_1-xCs_xPbI₃ thin films by one step method using additive (2)　　　　　　　　　　　　　　　
Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2017.2, First page：2665, Last page：2665, Aug. 2017
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2017.2.0_2665
DOI ID：10.11470/jsapmeeting.2017.2.0_2665, eISSN：2436-7613

Barium hydroxide hole blocking layer for front- and back-organic/crystalline Si heterojunction solar cells　　　　　　　　　　　　　　　
Jaker Hossain; Koji Kasahara; Daisuke Harada; A. T. M. Saiful Islam; Ryo Ishikawa; Keiji Ueno; Tatsuro Hanajiri; Yoshikata Nakajima; Yasuhiko Fujii; Masahide Tokuda; Hajime Shirai
JOURNAL OF APPLIED PHYSICS, Volume：122, Number：5, First page：055101, Aug. 2017, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1063/1.4985812
DOI ID：10.1063/1.4985812, ISSN：0021-8979, eISSN：1089-7550, ORCID：44072979, Web of Science ID：WOS:000407740600029

Sensitive Phonon-Based Probe for Structure Identification of 1T ' MoTe2　　　　　　　　　　　　　　　
Lin Zhou; Shengxi Huang; Yuki Tatsumi; Lijun Wu; Huaihong Guo; Ya-Qing Bie; Keiji Ueno; Teng Yang; Yimei Zhu; Jing Kong; Riichiro f Saito; Mildred Dresselhaus
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, Volume：139, Number：25, First page：8396, Last page：8399, Jun. 2017, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1021/jacs.7b03445
DOI ID：10.1021/jacs.7b03445, ISSN：0002-7863, Web of Science ID：WOS:000404809600004

Fabrication of {CH(NH2)(2)}(1-x)CsxPbI3 Perovskite Thin Films by Two-step Method and Its Application to Thin Film Solar Cells　　　　　　　　　　　　　　　
Ryo Ishikawa; Keiji Ueno; Hajime Shirai
CHEMISTRY LETTERS, Volume：46, Number：4, First page：612, Last page：615, Apr. 2017
English, Scientific journal
DOI：https://doi.org/10.1246/cl.161194
DOI ID：10.1246/cl.161194, ISSN：0366-7022, eISSN：1348-0715, SCOPUS ID：85016144027, Web of Science ID：WOS:000400134700012

High-performance organic-inorganic heterojunction solar cells with thin layered material additives　　　　　　　　　　　　　　　
Kimura Takahiro; Ishikawa Ryo; Shirai Hajime; Ueno Keiji
JSAP Annual Meetings Extended Abstracts, Volume：2017.1, First page：2664, Last page：2664, Mar. 2017
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2017.1.0_2664
DOI ID：10.11470/jsapmeeting.2017.1.0_2664, eISSN：2436-7613

Fabrication and characterization of FA_1-xCs_xPbI₃ thin films by one step method using additive　　　　　　　　　　　　　　　
Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2017.1, First page：2700, Last page：2700, Mar. 2017
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2017.1.0_2700
DOI ID：10.11470/jsapmeeting.2017.1.0_2700, eISSN：2436-7613

Long-lived optical coherent phonon mode in transition metal dichalcogenide MoTe₂　　　　　　　　　　　　　　　
Makino,K; Saito,Y; Horii,S; Fons,P; Kolobov,A. V; Ando,A; Ueno,K; Hase,M
Meeting Abstracts of the Physical Society of Japan, Volume：72, Number：0, First page：1300, Last page：1300, 2017
The Physical Society of Japan, Japanese, Scientific journal
DOI：https://doi.org/10.11316/jpsgaiyo.72.2.0_1300
DOI ID：10.11316/jpsgaiyo.72.2.0_1300, ISSN：2189-0803

Role of Isopropyl Alcohol Solvent in the Synthesis of Organic-Inorganic Halide CH(NH2)(2)PbIxBr3-x Perovskite Thin Films by a Two-Step Method　　　　　　　　　　　　　　　
Takanori Yamanaka; Kenta Masumori; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
JOURNAL OF PHYSICAL CHEMISTRY C, Volume：120, Number：44, First page：25371, Last page：25377, Nov. 2016
English, Scientific journal
DOI：https://doi.org/10.1021/acs.jpcc.6b07527
DOI ID：10.1021/acs.jpcc.6b07527, ISSN：1932-7447, SCOPUS ID：84994884896, Web of Science ID：WOS:000387737900022

Nafion-Modified PEDOT:PSS as a Transparent Hole-Transporting Layer for High-Performance Crystalline-Si/Organic Heterojunction Solar Cells with Improved Light Soaking Stability　　　　　　　　　　　　　　　
Jaker Hossain; Qiming Liu; Takuya Miura; Koji Kasahara; Daisuke Harada; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
ACS Applied Materials & Interfaces, Volume：8, Number：46, First page：31926, Last page：31934, Nov. 2016
English, Scientific journal
DOI：https://doi.org/10.1021/acsami.6b10272
DOI ID：10.1021/acsami.6b10272, ISSN：1944-8244, SCOPUS ID：84999115078, Web of Science ID：WOS:000388913900053

Monolayer 1 T-NbSe2 as a Mott insulator　　　　　　　　　　　　　　　
Yuki Nakata; Katsuaki Sugawara; Ryota Shimizu; Yoshinori Okada; Patrick Han; Taro Hitosugi; Keiji Ueno; Takafumi Sato; Takashi Takahashi
NPG ASIA MATERIALS, Volume：8, Nov. 2016
English, Scientific journal
DOI：https://doi.org/10.1038/am.2016.157
DOI ID：10.1038/am.2016.157, ISSN：1884-4049, eISSN：1884-4057, SCOPUS ID：84994571030, Web of Science ID：WOS:000387402500001

Synthesis of High-Quality Large-Area Homogenous 1T ' MoTe2 from Chemical Vapor Deposition　　　　　　　　　　　　　　　
Lin Zhou; Ahmad Zubair; Ziqiang Wang; Xu Zhang; Fangping Ouyang; Kai Xu; Wenjing Fang; Keiji Ueno; Ju Li; Tomas Palacios; Jing Kong; Mildred S. Dresselhaus
ADVANCED MATERIALS, Volume：28, Number：43, First page：9526, Last page：+, Nov. 2016
English, Scientific journal
DOI：https://doi.org/10.1002/adma.201602687
DOI ID：10.1002/adma.201602687, ISSN：0935-9648, eISSN：1521-4095, SCOPUS ID：84987638165, Web of Science ID：WOS:000391175000010

Nafion-Modified PEDOT:PSS/c-Si Solar Cells　　　　　　　　　　　　　　　
Liu Qiming; Hossain Jaker; Miura Takuya; Harada Daisuke; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2016.2, First page：3397, Last page：3397, Sep. 2016
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2016.2.0_3397
DOI ID：10.11470/jsapmeeting.2016.2.0_3397, eISSN：2436-7613

c-Si/PEDOT:PSS heterojunction solar cells　　　　　　　　　　　　　　　
Shirai Hajime; Liu Qiming; Hayashi Tsutomu; Ishikawa Ryo; Ueno Keiji
JSAP Annual Meetings Extended Abstracts, Volume：2016.2, First page：258, Last page：258, Sep. 2016
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2016.2.0_258
DOI ID：10.11470/jsapmeeting.2016.2.0_258, eISSN：2436-7613

Fabrication and characterization of FA_1-xCs_xPbI₃ thin films using two step method　　　　　　　　　　　　　　　
Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2016.2, First page：2491, Last page：2491, Sep. 2016
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2016.2.0_2491
DOI ID：10.11470/jsapmeeting.2016.2.0_2491, eISSN：2436-7613

Effect of substrate bias on mist deposition of conjugated polymer on textured crystalline-Si for efficient c-Si/organic heterojunction solar cells　　　　　　　　　　　　　　　
Tatsuya Ohki; Koki Ichikawa; Jaker Hossein; Yasuhiko Fujii; Tatsuro Hanajiri; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
PHYSICA STATUS SOLIDI A-APPLICATIONS AND MATERIALS SCIENCE, Volume：213, Number：7, First page：1922, Last page：1925, Jul. 2016
English, Scientific journal
DOI：https://doi.org/10.1002/pssa.201532951
DOI ID：10.1002/pssa.201532951, ISSN：1862-6300, eISSN：1862-6319, SCOPUS ID：84963730570, Web of Science ID：WOS:000385222900040

Correlation between the fine structure of spin-coated PEDOT:PSS and the photovoltaic performance of organic/crystalline-silicon heterojunction solar cells　　　　　　　　　　　　　　　
Shuji Funda; Tatsuya Ohki; Qiming Liu; Jaker Hossain; Yoshihiro Ishimaru; Keiji Ueno; Hajime Shirai
JOURNAL OF APPLIED PHYSICS, Volume：120, Number：3, Jul. 2016
English, Scientific journal
DOI：https://doi.org/10.1063/1.4958845
DOI ID：10.1063/1.4958845, ISSN：0021-8979, eISSN：1089-7550, SCOPUS ID：84979299024, Web of Science ID：WOS:000381382500003

Carrier Polarity Control in alpha-MoTe2 Schottky Junctions Based on Weak Fermi-Level Pinning　　　　　　　　　　　　　　　
Shu Nakaharai; Mahito Yamamoto; Keiji Ueno; Kazuhito Tsukagoshi
ACS APPLIED MATERIALS & INTERFACES, Volume：8, Number：23, First page：14732, Last page：14739, Jun. 2016
English, Scientific journal
DOI：https://doi.org/10.1021/acsami.6b02036
DOI ID：10.1021/acsami.6b02036, ISSN：1944-8244, eISSN：1944-8252, SCOPUS ID：84975299230, Web of Science ID：WOS:000378195000054

Self-Limiting Oxides on WSe2 as Controlled Surface Acceptors and Low-Resistance Hole Contacts　　　　　　　　　　　　　　　
Mahito Yamamoto; Shu Nakaharai; Keiji Ueno; Kazuhito Tsukagoshi
NANO LETTERS, Volume：16, Number：4, First page：2720, Last page：2727, Apr. 2016
English, Scientific journal
DOI：https://doi.org/10.1021/acs.nanolett.6b00390
DOI ID：10.1021/acs.nanolett.6b00390, ISSN：1530-6984, eISSN：1530-6992, SCOPUS ID：84964914034, Web of Science ID：WOS:000374274600088

Deposition process of PEDOT:PSS on c-Si by Chemical Mist Deposition　　　　　　　　　　　　　　　
Ichikawa Koki; Ohki Tatsuya; Hossain Jaker; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2016.1, First page：3710, Last page：3710, Mar. 2016
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2016.1.0_3710
DOI ID：10.11470/jsapmeeting.2016.1.0_3710, eISSN：2436-7613

Plasma CVD of a-SiOH as AR coating layer for c-Si/PEDOT:PSS solar cells　　　　　　　　　　　　　　　
Kasahara Koji; Hossain Jaker; Liu Qiming; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2016.1, First page：3711, Last page：3711, Mar. 2016
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2016.1.0_3711
DOI ID：10.11470/jsapmeeting.2016.1.0_3711, eISSN：2436-7613

Fabrication of back-contact c-Si/PEDOT:PSS heterojunction solar cells　　　　　　　　　　　　　　　
Hossain Jaker; Kasahara Koji; Liu Qiming; Ishikawa Ryo; Ueno Keiji; Kaneko Tetsuya; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2016.1, First page：3709, Last page：3709, Mar. 2016
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2016.1.0_3709
DOI ID：10.11470/jsapmeeting.2016.1.0_3709, eISSN：2436-7613

Fabrication and characterization of (FAPbI₃)_1-x(MAPbBr₃)_x thin film from porous PbI₂ thin film as precursor　　　　　　　　　　　　　　　
Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2016.1, First page：2618, Last page：2618, Mar. 2016
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2016.1.0_2618
DOI ID：10.11470/jsapmeeting.2016.1.0_2618, eISSN：2436-7613

Investigating the chemical mist deposition technique for poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) on textured crystalline-silicon for organic/crystalline-silicon heterojunction solar cells　　　　　　　　　　　　　　　
Jaker Hossain; Tatsuya Ohki; Koki Ichikawa; Kazuhiko Fujiyama; Keiji Ueno; Yasuhiko Fujii; Tatsuro Hanajiri; Hajime Shirai
JAPANESE JOURNAL OF APPLIED PHYSICS, Volume：55, Number：3, Mar. 2016
English, Scientific journal
DOI：https://doi.org/10.7567/JJAP.55.031601
DOI ID：10.7567/JJAP.55.031601, ISSN：0021-4922, eISSN：1347-4065, SCOPUS ID：84961990487, Web of Science ID：WOS:000370491100017

Solution-processed crystalline silicon double-heterojunction solar cells　　　　　　　　　　　　　　　
Ramesh Devkota; Qiming Liu; Tatsuya Ohki; Jaker Hossain; Keiji Ueno; Hajime Shirai
APPLIED PHYSICS EXPRESS, Volume：9, Number：2, Feb. 2016
English, Scientific journal
DOI：https://doi.org/10.7567/APEX.9.022301
DOI ID：10.7567/APEX.9.022301, ISSN：1882-0778, eISSN：1882-0786, SCOPUS ID：84956984570, Web of Science ID：WOS:000371297800013

19aAJ-4 Electronic structure of Bi ultrathin film on transition-metal dichalcogenide 1T-TaS_2 studied by high-resolution ARPES　　　　　　　　　　　　　　　
Yamada K.; Trang C.; Souma S.; Sugawara K.; Sato T.; Ueno K.; Takahashi T.
Meeting Abstracts of the Physical Society of Japan, Volume：71, First page：2470, Last page：2470, 2016
The Physical Society of Japan (JPS), Japanese
DOI：https://doi.org/10.11316/jpsgaiyo.71.1.0_2470
DOI ID：10.11316/jpsgaiyo.71.1.0_2470, ISSN：2189-079X, CiNii Articles ID：110010058409, CiNii Books ID：AA12721570

20pBE-2 Thickness dependence of electronic states in NbSe_2 thin film studied by high-resolution ARPES　　　　　　　　　　　　　　　
Nakata Y.; Yamada K.; Kimizuka H.; Tanaka Y.; Sugawara K.; Souma S.; Sato T.; Shimizu R.; Hitosugi T.; Ueno K.; Takahashi T.
Meeting Abstracts of the Physical Society of Japan, Volume：71, First page：1868, Last page：1868, 2016
The Physical Society of Japan (JPS), Japanese
DOI：https://doi.org/10.11316/jpsgaiyo.71.1.0_1868
DOI ID：10.11316/jpsgaiyo.71.1.0_1868, ISSN：2189-079X, CiNii Articles ID：110010057838, CiNii Books ID：AA12721570

Electronic structure of atomic layer NbSe₂ thin film studied by high-resolution ARPES　　　　　　　　　　　　　　　
Nakata Y.; Sugawara K.; Souma S.; Sato T.; Shimuzu R.; Hitosugi T.; Ueno K.; Takahashi T.
Meeting Abstracts of the Physical Society of Japan, Volume：71, First page：1171, Last page：1171, 2016
遷移金属ダイカルコゲナイドNbSe_2_の原子層化に伴う電子状態の変化を明らかにするために、分子線エピタキシー法を用いて2層グラフェン上に単層NbSe_2_薄膜を作製し、その電子状態を高分解能ARPESにより測定した。その結果、単層NbSe_2_において、バルクとは大きく異なる特異な電子状態を観測した。講演では、バルクの実験結果およびバンド計算との比較から、特異な電子状態の起源について議論する。

The Physical Society of Japan, Japanese
DOI：https://doi.org/10.11316/jpsgaiyo.71.2.0_1171
DOI ID：10.11316/jpsgaiyo.71.2.0_1171, CiNii Articles ID：130006243828

High-resolution ARPES study of NbSe₂ thin film grown on Graphene　　　　　　　　　　　　　　　
Nakata Y.; Sugawara K.; Souma S.; Sato T.; Shimuzu R.; Hitosugi T.; Ueno K.; Takahashi T.
Meeting Abstracts of the Physical Society of Japan, Volume：71, First page：1393, Last page：1393, 2016
バルクの2H-NbSe_2_は約33K以下でCDW相へ転移することが知られているが、膜厚の減少に伴うCDWの変化については未解明である。今回我々は、2層グラフェン上にMBE法により単層及び多層のNbSe_2_薄膜を作製し、それらの電子状態を高分解能ARPESによって測定した。講演では、詳細な電子構造の実験結果を報告するとともに、膜厚に依存したCDWの変化について議論する。

The Physical Society of Japan, Japanese
DOI：https://doi.org/10.11316/jpsgaiyo.71.2.0_1393
DOI ID：10.11316/jpsgaiyo.71.2.0_1393, CiNii Articles ID：130006244003

Anomalous band structure of Bi ultrathin film on 1T-TaS₂ studied by high-resolution ARPES　　　　　　　　　　　　　　　
Yamada K.; Trang C.; Souma S.; Sugawara K.; Sato T.; Ueno K.; Takahashi T.
Meeting Abstracts of the Physical Society of Japan, Volume：71, First page：2310, Last page：2310, 2016
V族のBi薄膜は、黒リン同様に興味深い相変態を示すことが知られており、(111)方位だけではなく、(110)方位の超薄膜においても2次元のトポロジカル絶縁体(TI)相の発現が期待され、注目を集めている。今回我々は、1T-TaS_2_やSi基板上にBi(110)超薄膜を作製し、電子構造を高分解能ARPESで測定した。その結果、TI相を予測するバンド計算と類似した電子構造を見出した。講演では、Bi(110)超薄膜のバンド構造における基板・温度依存性を詳しく議論する。

The Physical Society of Japan, Japanese
DOI：https://doi.org/10.11316/jpsgaiyo.71.2.0_2310
DOI ID：10.11316/jpsgaiyo.71.2.0_2310, CiNii Articles ID：130006244991

Introduction to the Growth of Bulk Single Crystals of Two-Dimensional Transition-Metal Dichalcogenides　　　　　　　　　　　　　　　
Keiji Ueno
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：84, Number：12, Dec. 2015
English, Scientific journal
DOI：https://doi.org/10.7566/JPSJ.84.121015
DOI ID：10.7566/JPSJ.84.121015, ISSN：0031-9015, SCOPUS ID：84957074331, Web of Science ID：WOS:000365804100015

Origin of Noise in Layered MoTe2 Transistors and its Possible Use for Environmental Sensors　　　　　　　　　　　　　　　
Yen-Fu Lin; Yong Xu; Che-Yi Lin; Yuen-Wuu Suen; Mahito Yamamoto; Shu Nakaharai; Keiji Ueno; Kazuhito Tsukagoshi
ADVANCED MATERIALS, Volume：27, Number：42, First page：6612, Last page：+, Nov. 2015
English, Scientific journal
DOI：https://doi.org/10.1002/adma.201502677
DOI ID：10.1002/adma.201502677, ISSN：0935-9648, eISSN：1521-4095, SCOPUS ID：84946781252, Web of Science ID：WOS:000364700200007

Changes in structure and chemical composition of alpha-MoTe2 and beta-MoTe2 during heating in vacuum conditions　　　　　　　　　　　　　　　
Keiji Ueno; Koji Fukushima
APPLIED PHYSICS EXPRESS, Volume：8, Number：9, Sep. 2015
English, Scientific journal
DOI：https://doi.org/10.7567/APEX.8.095201
DOI ID：10.7567/APEX.8.095201, ISSN：1882-0778, eISSN：1882-0786, SCOPUS ID：84940992838, Web of Science ID：WOS:000362184700026

Highly Efficient Solution-Processed Poly(3,4-ethylenedio-xythiophene):Poly(styrenesulfonate)/Crystalline-Silicon Heterojunction Solar Cells with Improved Light-Induced Stability　　　　　　　　　　　　　　　
Qiming Liu; Ryo Ishikawa; Shuji Funada; Tatsuya Ohki; Keiji Ueno; Hajime Shirai
ADVANCED ENERGY MATERIALS, Volume：5, Number：17, Sep. 2015
English, Scientific journal
DOI：https://doi.org/10.1002/aenm.201500744
DOI ID：10.1002/aenm.201500744, ISSN：1614-6832, eISSN：1614-6840, SCOPUS ID：84941186958, Web of Science ID：WOS:000361226700013

Construction of van der Waals magnetic tunnel junction using ferromagnetic layered dichalcogenide　　　　　　　　　　　　　　　
Miho Arai; Rai Moriya; Naoto Yabuki; Satoru Masubuchi; Keiji Ueno; Tomoki Machida
APPLIED PHYSICS LETTERS, Volume：107, Number：10, Sep. 2015
English, Scientific journal
DOI：https://doi.org/10.1063/1.4930311
DOI ID：10.1063/1.4930311, ISSN：0003-6951, eISSN：1077-3118, SCOPUS ID：84941356974, Web of Science ID：WOS:000361640200042

Large-Area Synthesis of High-Quality Uniform Few-Layer MoTe2　　　　　　　　　　　　　　　
Lin Zhou; Kai Xu; Ahmad Zubair; Albert D. Liao; Wenjing Fang; Fangping Ouyang; Yi-Hsien Lee; Keiji Ueno; Riichiro Saito; Tomas Palacios; Jing Kong; Mildred S. Dresselhaus
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, Volume：137, Number：37, First page：11892, Last page：11895, Sep. 2015
English, Scientific journal
DOI：https://doi.org/10.1021/jacs.5b07452
DOI ID：10.1021/jacs.5b07452, ISSN：0002-7863, SCOPUS ID：84942239142, Web of Science ID：WOS:000361930000010

C-Si/PEDOT: PSS heterojunction solar cells with a MoO₃ AR coating using chemical mist deposition method　　　　　　　　　　　　　　　
Ichikawa Koki; Ohki Tatsuya; Hossain Jaker; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2015.2, First page：2392, Last page：2392, Aug. 2015
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2015.2.0_2392
DOI ID：10.11470/jsapmeeting.2015.2.0_2392, eISSN：2436-7613

Fabrication of metal-oxide/PEDOT:PSS/Si heterojunction tandem solar cells　　　　　　　　　　　　　　　
yagi daichi; Kimura Takahiro; Ishikawa Ryo; Shirai Hajime; Ueno Keiji
JSAP Annual Meetings Extended Abstracts, Volume：2015.2, First page：2432, Last page：2432, Aug. 2015
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2015.2.0_2432
DOI ID：10.11470/jsapmeeting.2015.2.0_2432, eISSN：2436-7613

High-performance heterojunction solar cells using layered chalcogenide atomic layer　　　　　　　　　　　　　　　
Kimura Takahiro; Yagi Daichi; Ishikawa Ryo; Shirai Hajime; Ueno Keiji
JSAP Annual Meetings Extended Abstracts, Volume：2015.2, First page：2431, Last page：2431, Aug. 2015
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2015.2.0_2431
DOI ID：10.11470/jsapmeeting.2015.2.0_2431, eISSN：2436-7613

Fine Structure of PEDOT:PSS Modified by PTSA/DMSO Cosolvent　　　　　　　　　　　　　　　
Funada Shuji; Liu Qiming; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2015.2, First page：2394, Last page：2394, Aug. 2015
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2015.2.0_2394
DOI ID：10.11470/jsapmeeting.2015.2.0_2394, eISSN：2436-7613

Fabrication and characterization of (FAPbI₃)_1-x(MAPbBr₃)_x thin film by two step method　　　　　　　　　　　　　　　
Ishikawa Ryo; Yamanaka Takanori; Honda Zentaro; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2015.2, First page：148, Last page：148, Aug. 2015
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2015.2.0_148
DOI ID：10.11470/jsapmeeting.2015.2.0_148, eISSN：2436-7613

Growth of single-layer graphitic carbon nitride on single crystal substrates　　　　　　　　　　　　　　　
Katoh Tokio; Obata Seiji; Ueno Keiji; Saiki Koichiro
JSAP Annual Meetings Extended Abstracts, Volume：2015.2, First page：3367, Last page：3367, Aug. 2015
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2015.2.0_3367
DOI ID：10.11470/jsapmeeting.2015.2.0_3367, eISSN：2436-7613

Electrostatically Reversible Polarity of Ambipolar alpha-MoTe2 Transistors　　　　　　　　　　　　　　　
Shu Nakaharai; Mahito Yamamoto; Keiji Ueno; Yen-Fu Lin; Song-Lin Li; Kazuhito Tsukagoshi
ACS NANO, Volume：9, Number：6, First page：5976, Last page：5983, Jun. 2015
English, Scientific journal
DOI：https://doi.org/10.1021/acsnano.5b00736
DOI ID：10.1021/acsnano.5b00736, ISSN：1936-0851, eISSN：1936-086X, SCOPUS ID：84935017328, Web of Science ID：WOS:000356988500038

Double resonance Raman modes in monolayer and few-layer MoTe2　　　　　　　　　　　　　　　
Huaihong Guo; Teng Yang; Mahito Yamamoto; Lin Zhou; Ryo Ishikawa; Keiji Ueno; Kazuhito Tsukagoshi; Zhidong Zhang; Mildred S. Dresselhaus; Riichiro Saito
PHYSICAL REVIEW B, Volume：91, Number：20, May 2015
English, Scientific journal
DOI：https://doi.org/10.1103/PhysRevB.91.205415
DOI ID：10.1103/PhysRevB.91.205415, ISSN：1098-0121, eISSN：1550-235X, SCOPUS ID：84929598374, Web of Science ID：WOS:000354365100005

Self-Limiting Layer-by-Layer Oxidation of Atomically Thin WSe2　　　　　　　　　　　　　　　
Mahito Yamamoto; Sudipta Dutta; Shinya Aikawa; Shu Nakaharai; Katsunori Wakabayashi; Michael S. Fuhrer; Keiji Ueno; Kazuhito Tsukagoshi
NANO LETTERS, Volume：15, Number：3, First page：2067, Last page：2073, Mar. 2015
English, Scientific journal
DOI：https://doi.org/10.1021/nl5049753
DOI ID：10.1021/nl5049753, ISSN：1530-6984, eISSN：1530-6992, SCOPUS ID：84924630786, Web of Science ID：WOS:000351188000095

FTIR-ATR study on c-Si/PEDOT:PSS interface and its PV performance　　　　　　　　　　　　　　　
Funada Shuji; Ohki Tatuya; Ichikawa Kouki; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2015.1, First page：2513, Last page：2513, Feb. 2015
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2015.1.0_2513
DOI ID：10.11470/jsapmeeting.2015.1.0_2513, eISSN：2436-7613

Fabrication and characterization of CH(NH₂)₂Pb(I_1-xBr_x)₃ thin film　　　　　　　　　　　　　　　
Yamanaka Takanori; Ishikawa Ryou; Honda Zentarou; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2015.1, First page：2226, Last page：2226, Feb. 2015
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2015.1.0_2226
DOI ID：10.11470/jsapmeeting.2015.1.0_2226, eISSN：2436-7613

Textured-Si/PEDOT:PSS heterojunction solar cells using chemical mist deposition method　　　　　　　　　　　　　　　
Ohki Tatsuya; Ichikawa Koki; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2015.1, First page：2512, Last page：2512, Feb. 2015
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2015.1.0_2512
DOI ID：10.11470/jsapmeeting.2015.1.0_2512, eISSN：2436-7613

Degradation mechanism of Si/PEDOT:PSS heterojunction solar cells　　　　　　　　　　　　　　　
Takei Yuki; Yagi Daichi; Ishikawa Ryo; Shirai Hajime; Ueno Keiji
JSAP Annual Meetings Extended Abstracts, Volume：2015.1, First page：2510, Last page：2510, Feb. 2015
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2015.1.0_2510
DOI ID：10.11470/jsapmeeting.2015.1.0_2510, eISSN：2436-7613

Ferroelectric polymer inserted c-Si/PEDOT:PSS heterojunction solar cells　　　　　　　　　　　　　　　
Masumori Kenta; Liu Qiming; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2015.1, First page：2514, Last page：2514, Feb. 2015
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2015.1.0_2514
DOI ID：10.11470/jsapmeeting.2015.1.0_2514, eISSN：2436-7613

Optical microscope observation of Diacetylene thin film growth on Si(111) substrate　　　　　　　　　　　　　　　
Kamata Yuto; Obata Seiji; Ueno Keiji; Saiki Koichiro
JSAP Annual Meetings Extended Abstracts, Volume：2015.1, First page：2166, Last page：2166, Feb. 2015
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2015.1.0_2166
DOI ID：10.11470/jsapmeeting.2015.1.0_2166, eISSN：2436-7613

Fabrication of organic/inorganic hybrid CMOS devices using solution-processed graphene electrodes
Koichi Suganuma; Hajime Shirai; Keiji Ueno
IEEJ Transactions on Electronics, Information and Systems, Volume：135, Number：2, First page：156, Last page：159, Feb. 2015
Institute of Electrical Engineers of Japan, Japanese, Scientific journal
DOI：https://doi.org/10.1541/ieejeiss.135.156
DOI ID：10.1541/ieejeiss.135.156, ISSN：1348-8155, SCOPUS ID：84922239834

17pAH-4 High-resolution ARPES study of NbSe_2 thin film　　　　　　　　　　　　　　　
Nakata Y.; Yamada K.; Kimizuka H.; Tanaka Y.; Sugawara K.; Souma S.; Sato T.; Ueno K.; Takahashi T.
Meeting Abstracts of the Physical Society of Japan, Volume：70, First page：1592, Last page：1592, 2015
The Physical Society of Japan (JPS), Japanese
DOI：https://doi.org/10.11316/jpsgaiyo.70.2.0_1592
DOI ID：10.11316/jpsgaiyo.70.2.0_1592, ISSN：2189-079X, CiNii Articles ID：110010029283, CiNii Books ID：AA12721570

18aCE-3 Bi ultrathin film on 1T-TaS_2 studied by high-resolution ARPES　　　　　　　　　　　　　　　
Yamada K.; C. Trang; Souma S.; Sugawara K.; Sato T.; Ueno K.; Takahashi T.
Meeting Abstracts of the Physical Society of Japan, Volume：70, First page：1230, Last page：1230, 2015
The Physical Society of Japan (JPS), Japanese
DOI：https://doi.org/10.11316/jpsgaiyo.70.2.0_1230
DOI ID：10.11316/jpsgaiyo.70.2.0_1230, ISSN：2189-079X, CiNii Articles ID：110010029080, CiNii Books ID：AA12721570

Retraction to Poly(3-hexylthiophene) films by electrospray deposition for crystalline silicon/organic hybrid junction solar cells [Phys. Status Solidi C, 2071, (2012) 10-11], DOI: 10.1002/pssc.201200129
Taiga Hiate; Naoto Miyauchi; Zeguo Tang; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
Physica Status Solidi (C) Current Topics in Solid State Physics, Volume：12, First page：1191, Last page：1191, Jan. 2015
DOI：https://doi.org/10.1002/pssc.201570094
DOI ID：10.1002/pssc.201570094, ISSN：1862-6351, SCOPUS ID：84939653832

Efficient organic/polycrystalline silicon hybrid solar cells　　　　　　　　　　　　　　　
Qiming Liu; Tatsuya Ohki; Dequan Liu; Hiromitsu Sugawara; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
NANO ENERGY, Volume：11, First page：260, Last page：266, Jan. 2015
English, Scientific journal
DOI：https://doi.org/10.1016/j.nanoen.2014.10.032
DOI ID：10.1016/j.nanoen.2014.10.032, ISSN：2211-2855, eISSN：2211-3282, SCOPUS ID：84911930097, Web of Science ID：WOS:000351194300030

van der Waals Junctions of Layered 2D Materials for Functional Devices　　　　　　　　　　　　　　　
Tomoki Machida; Rai Moriya; Miho Arai; Yohta Sata; Takehiro Yamaguchi; Naoto Yabuki; Sei Morikawa; Satoru Masubuchi; Keiji Ueno
2015 IEEE INTERNATIONAL ELECTRON DEVICES MEETING (IEDM), Volume：2016-February, 2015
English, International conference proceedings
DOI：https://doi.org/10.1109/IEDM.2015.7409783
DOI ID：10.1109/IEDM.2015.7409783, ISSN：0163-1918, SCOPUS ID：84964038603, Web of Science ID：WOS:000380472500177

Erratum: Optical and carrier transport properties of graphene oxide based crystalline-Si/organic Schottky junction solar cells (Journal of Applied Physics (2013) 114 (234506))
I. Khatri; Z. Tang; T. Hiate; Q. Liu; R. Ishikawa; K. Ueno; H. Shirai
Journal of Applied Physics, Volume：116, Number：23, Dec. 2014
American Institute of Physics Inc., English, Scientific journal
DOI：https://doi.org/10.1063/1.4900524
DOI ID：10.1063/1.4900524, ISSN：1089-7550, SCOPUS ID：84919683738

Improved performance of poly(3,4-ethylenedioxythiophene):poly(stylene sulfonate)/n-Si hybrid solar cell by incorporating silver nanoparticles　　　　　　　　　　　　　　　
Ishwor Khatri; Qiming Liu; Keiji Ueno; Hajime Shirai
JAPANESE JOURNAL OF APPLIED PHYSICS, Volume：53, Number：11, Nov. 2014
English, Scientific journal
DOI：https://doi.org/10.7567/JJAP.53.110305
DOI ID：10.7567/JJAP.53.110305, ISSN：0021-4922, eISSN：1347-4065, SCOPUS ID：84909957557, Web of Science ID：WOS:000346462200005

Mist transport and sticking process of PEDOT:PSS on textured c-Si using CMD Ⅱ　　　　　　　　　　　　　　　
Ohki Tatsuya; Sugawara Hiromitsu; Ichikawa Koki; Ku Pei-ju; Fujiyama Kazuhiko; Hanajiri Tatsuro; Ishikawa Ryo; Ueno Keiji; Sun Kienwen; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2014.2, First page：3474, Last page：3474, Sep. 2014
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2014.2.0_3474
DOI ID：10.11470/jsapmeeting.2014.2.0_3474, eISSN：2436-7613

Perovskite photovoltaic cells with electron-transporting layers of zinc oxide nanoparticles(2)　　　　　　　　　　　　　　　
Ishikawa Ryo; Yamanaka Takanori; Honda Zentaro; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2014.2, First page：2494, Last page：2494, Sep. 2014
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2014.2.0_2494
DOI ID：10.11470/jsapmeeting.2014.2.0_2494, eISSN：2436-7613

Improvement in the performance of Si/PEDOT:PSS heterojunction solar cells by inserting metal oxide layers　　　　　　　　　　　　　　　
Yagi Daichi; Takei Yuki; Ishikawa Ryo; Shirai Hajime; Ueno Keiji
JSAP Annual Meetings Extended Abstracts, Volume：2014.2, First page：2434, Last page：2434, Sep. 2014
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2014.2.0_2434
DOI ID：10.11470/jsapmeeting.2014.2.0_2434, eISSN：2436-7613

Degradation of Si/PEDOT:PSS heterojunction solar cells under the illumination　　　　　　　　　　　　　　　
Takei Yuki; Yagi Daichi; Ishikawa Ryo; Shirai Hajime; Ueno Keiji
JSAP Annual Meetings Extended Abstracts, Volume：2014.2, First page：2419, Last page：2419, Sep. 2014
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2014.2.0_2419
DOI ID：10.11470/jsapmeeting.2014.2.0_2419, eISSN：2436-7613

PEDOT:PSS/poly-Si heterojunction solar cells　　　　　　　　　　　　　　　
Liu Qiming; Ohki Tatsuya; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2014.2, First page：3460, Last page：3460, Sep. 2014
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2014.2.0_3460
DOI ID：10.11470/jsapmeeting.2014.2.0_3460, eISSN：2436-7613

Improved photovoltaic response by incorporating green tea modified multiwalled carbon nanotubes in organic-inorganic hybrid solar cell　　　　　　　　　　　　　　　
Ishwor Khatri; Qiming Liu; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
CANADIAN JOURNAL OF PHYSICS, Volume：92, Number：7-8, First page：849, Last page：852, Jul. 2014
English, Scientific journal
DOI：https://doi.org/10.1139/cjp-2013-0506
DOI ID：10.1139/cjp-2013-0506, ISSN：0008-4204, eISSN：1208-6045, SCOPUS ID：84904297439, Web of Science ID：WOS:000339379500064

Self assembled silver nanowire mesh as top electrode for organic-inorganic hybrid solar cell　　　　　　　　　　　　　　　
Ishwor Khatri; Qiming Liu; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
CANADIAN JOURNAL OF PHYSICS, Volume：92, Number：7-8, First page：867, Last page：870, Jul. 2014
English, Scientific journal
DOI：https://doi.org/10.1139/cjp-2013-0564
DOI ID：10.1139/cjp-2013-0564, ISSN：0008-4204, eISSN：1208-6045, SCOPUS ID：84904317577, Web of Science ID：WOS:000339379500068

Self-assembled silver nanowires as top electrode for poly(3,4-ethylenedioxythiophene): poly(stylenesulfonate)/n-silicon solar cell　　　　　　　　　　　　　　　
Ishwor Khatri; Ayo Hoshino; Fumiya Watanabe; Qiming Liu; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
THIN SOLID FILMS, Volume：558, First page：306, Last page：310, May 2014
English, Scientific journal
DOI：https://doi.org/10.1016/j.tsf.2014.02.073
DOI ID：10.1016/j.tsf.2014.02.073, ISSN：0040-6090, SCOPUS ID：84898785080, Web of Science ID：WOS:000334314100047

Ambipolar MoTe2 Transistors and Their Applications in Logic Circuits　　　　　　　　　　　　　　　
Yen-Fu Lin; Yong Xu; Sheng-Tsung Wang; Song-Lin Li; Mahito Yamamoto; Alex Aparecido-Ferreira; Wenwu Li; Huabin Sun; Shu Nakaharai; Wen-Bin Jian; Keiji Ueno; Kazuhito Tsukagoshi
ADVANCED MATERIALS, Volume：26, Number：20, First page：3263, Last page：+, May 2014
English, Scientific journal
DOI：https://doi.org/10.1002/adma.201305845
DOI ID：10.1002/adma.201305845, ISSN：0935-9648, eISSN：1521-4095, SCOPUS ID：84901493242, Web of Science ID：WOS:000336999800012

Strong Enhancement of Raman Scattering from a Bulk-Inactive Vibrational Mode in Few-Layer MoTe2　　　　　　　　　　　　　　　
Mahito Yamamoto; Sheng Tsung Wang; Meiyan Ni; Yen-Fu Lin; Song-Lin Li; Shinya Aikawa; Wen-Bin Jian; Keiji Ueno; Katsunori Wakabayashi; Kazuhito Tsukagoshi
ACS NANO, Volume：8, Number：4, First page：3895, Last page：3903, Apr. 2014
English, Scientific journal
DOI：https://doi.org/10.1021/nn5007607
DOI ID：10.1021/nn5007607, ISSN：1936-0851, eISSN：1936-086X, SCOPUS ID：84899451693, Web of Science ID：WOS:000334990600087

2D map of photovoltaic parameters in c-Si/PEDOT:PSS heterojunction solar cells　　　　　　　　　　　　　　　
Liu Qiming; Ohki Tatsuya; Kakinuma Takayuki; Ishwor Khatri; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2014.1, First page：3530, Last page：3530, Mar. 2014
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2014.1.0_3530
DOI ID：10.11470/jsapmeeting.2014.1.0_3530, eISSN：2436-7613

Preparation of (CH₃NH₃)PbI₃ thin films and it’s photoconductive property　　　　　　　　　　　　　　　
Yamanaka Takanori; Watanabe Kyouhei; Qiming Liu; Ishikawa Ryou; Honda Zentarou; Ueno Keizi; Shirai Hazime
JSAP Annual Meetings Extended Abstracts, Volume：2014.1, First page：2239, Last page：2239, Mar. 2014
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2014.1.0_2239
DOI ID：10.11470/jsapmeeting.2014.1.0_2239, eISSN：2436-7613

2D mapping of photovoltaic performance of c-Si/PEDOT:PSS heterojunction solar cells　　　　　　　　　　　　　　　
Ohki Tatsuya; Miyauchi Naoto; Sugawara Hiromitsu; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2014.1, First page：3529, Last page：3529, Mar. 2014
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2014.1.0_3529
DOI ID：10.11470/jsapmeeting.2014.1.0_3529, eISSN：2436-7613

Perovskite photovoltaic cells with electron-transporting layers of zinc oxide nanoparticles　　　　　　　　　　　　　　　
Ishikawa Ryo; Yamanaka Takanori; Honda Zentaro; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2014.1, First page：2446, Last page：2446, Mar. 2014
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2014.1.0_2446
DOI ID：10.11470/jsapmeeting.2014.1.0_2446, eISSN：2436-7613

Gas phase diagnostics of PEDOT:PSS mist transport and morphology on textured Si　　　　　　　　　　　　　　　
Sugawara Hiromitsu; Miyauchi Naoto; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2014.1, First page：3528, Last page：3528, Mar. 2014
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2014.1.0_3528
DOI ID：10.11470/jsapmeeting.2014.1.0_3528, eISSN：2436-7613

Real-time characterization of mist-deposited graphene oxide (GO) by spectroscopic ellipsometry　　　　　　　　　　　　　　　
Funada Shuji; Hiate Taiga; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2014.1, First page：3631, Last page：3631, Mar. 2014
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2014.1.0_3631
DOI ID：10.11470/jsapmeeting.2014.1.0_3631, eISSN：2436-7613

The effect of inserting a-Si:H for c-Si/PEDOT:PSS heterojunction solar cells　　　　　　　　　　　　　　　
Watanabe Kyohei; Liu Qiming; Khatri Ishwor; Ishikawa Ryo; Ueno Keiji; Shirai Hajime
JSAP Annual Meetings Extended Abstracts, Volume：2014.1, First page：3565, Last page：3565, Mar. 2014
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2014.1.0_3565
DOI ID：10.11470/jsapmeeting.2014.1.0_3565, eISSN：2436-7613

Preparation of graphene films from solid state precursors on Cu foils by Joule-heating method　　　　　　　　　　　　　　　
Baba Tomoya; Saiki Koichiro; Ueno Keiji
JSAP Annual Meetings Extended Abstracts, Volume：2014.1, First page：3606, Last page：3606, Mar. 2014
The Japan Society of Applied Physics, Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2014.1.0_3606
DOI ID：10.11470/jsapmeeting.2014.1.0_3606, eISSN：2436-7613

Real-time measurement of optical anisotropy during film growth using a chemical mist deposition of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)　　　　　　　　　　　　　　　
T. Hiate; N. Miyauchi; Q. Liu; R. Ishikawa; K. Ueno; H. Shirai
JOURNAL OF APPLIED PHYSICS, Volume：115, Number：12, Mar. 2014
English, Scientific journal
DOI：https://doi.org/10.1063/1.4869956
DOI ID：10.1063/1.4869956, ISSN：0021-8979, eISSN：1089-7550, SCOPUS ID：84898045854, Web of Science ID：WOS:000333901100023

原子層エレクトロニクスに向けたカルコゲナイド系層状物質の基礎物性と薄膜形成手法　　　　　　　　　　　　　　　
上野啓司; 塚越一仁
応用物理, Volume：83, Number：4, First page：274, Last page：278, 2014, [Reviewed]
応用物理学会, Japanese
ISSN：0369-8009, CiNii Articles ID：40020062119, CiNii Books ID：AN00026679, ORCID：35732259

Solution-processed graphene oxide as a possible material for photovoltaic device　　　　　　　　　　　　　　　
Shirai, H.; Ueno, K.
Journal of the Institute of Electronics, Information and Communication Engineers, Volume：97, Number：3, First page：215, Last page：221, Jan. 2014
Scientific journal
ISSN：0913-5693, ORCID：33901965, SCOPUS ID：84901430610

Optical and carrier transport properties of graphene oxide based crystalline-Si/organic Schottky junction solar cells
I. Khatri; Z. Tang; T. Hiate; Q. Liu; R. Ishikawa; K. Ueno; H. Shirai
Journal of Applied Physics, Volume：114, Number：23, Dec. 2013
English, Scientific journal
DOI：https://doi.org/10.1063/1.4847515
DOI ID：10.1063/1.4847515, ISSN：0021-8979, SCOPUS ID：84891389994

Improved photovoltaic performance of crystalline-Si/organic Schottky junction solar cells using ferroelectric polymers　　　　　　　　　　　　　　　
Q. Liu; I. Khatri; R. Ishikawa; A. Fujimori; K. Ueno; K. Manabe; H. Nishino; H. Shirai
APPLIED PHYSICS LETTERS, Volume：103, Number：16, Oct. 2013
English, Scientific journal
DOI：https://doi.org/10.1063/1.4826323
DOI ID：10.1063/1.4826323, ISSN：0003-6951, eISSN：1077-3118, SCOPUS ID：84886421198, Web of Science ID：WOS:000326148700086

結晶Si/PEDOT:PSSへテロ接合太陽電池の水素パッシベーション効果　　　　　　　　　　　　　　　
渡辺恭平; 山中孝紀; 石川良; 上野啓司; 白井肇
Volume：2013.2, First page：4218, Last page：4218, Aug. 2013
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2013.2.0_4218
DOI ID：10.11470/jsapmeeting.2013.2.0_4218, eISSN：2436-7613

パリレン積層膜による結晶Si/PEDOT:PSSヘテロ接合太陽電池の耐久性向上　　　　　　　　　　　　　　　
武居雄輝; 石川良; 白井肇; 上野啓司
Volume：2013.2, First page：3338, Last page：3338, Aug. 2013
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2013.2.0_3338
DOI ID：10.11470/jsapmeeting.2013.2.0_3338, eISSN：2436-7613

基板面方位による結晶Si/PEDOT:PSSヘテロ接合太陽電池の特性変化　　　　　　　　　　　　　　　
石川良; 柴山拓; 白井肇; 上野啓司
Volume：2013.2, First page：3332, Last page：3332, Aug. 2013
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2013.2.0_3332
DOI ID：10.11470/jsapmeeting.2013.2.0_3332, eISSN：2436-7613

分光エリプソメトリーにおける酸化グラフェンの評価　　　　　　　　　　　　　　　
船田修司; 日當大我; 上野啓司; 石川良; 白井肇
Volume：2013.2, First page：4266, Last page：4266, Aug. 2013
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2013.2.0_4266
DOI ID：10.11470/jsapmeeting.2013.2.0_4266, eISSN：2436-7613

酸化チタンナノ粒子を電子輸送層とする逆型有機薄膜太陽電池　　　　　　　　　　　　　　　
石川良; 白井肇; 上野啓司
Volume：2013.2, First page：3377, Last page：3377, Aug. 2013
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2013.2.0_3377
DOI ID：10.11470/jsapmeeting.2013.2.0_3377, eISSN：2436-7613

Optical anisotropy in solvent-modified poly(3,4-ethylenedioxythiophene): poly(styrenesulfonic acid) and its effect on the photovoltaic performance of crystalline silicon/organic heterojunction solar cells　　　　　　　　　　　　　　　
Qiming Liu; Takashi Imamura; Taiga Hiate; Ishwor Khatri; Zeguo Tang; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
APPLIED PHYSICS LETTERS, Volume：102, Number：24, Jun. 2013
English, Scientific journal
DOI：https://doi.org/10.1063/1.4811355
DOI ID：10.1063/1.4811355, ISSN：0003-6951, SCOPUS ID：84879820777, Web of Science ID：WOS:000320962400113

Effects of molybdenum oxide molecular doping on the chemical structure of poly(3,4-ethylenedioxythiophene):poly(stylenesulfonate) and on carrier collection efficiency of silicon/poly(3,4-ethylenedioxythiophene): poly(stylenesulfonate) heterojunction solar cells　　　　　　　　　　　　　　　
Q. Liu; I. Khatri; R. Ishikawa; K. Ueno; H. Shirai
APPLIED PHYSICS LETTERS, Volume：102, Number：18, May 2013
English, Scientific journal
DOI：https://doi.org/10.1063/1.4804298
DOI ID：10.1063/1.4804298, ISSN：0003-6951, eISSN：1077-3118, SCOPUS ID：84877775124, Web of Science ID：WOS:000320439900081

可溶性グラフェンを基盤材料に用いたZnO系TFT　　　　　　　　　　　　　　　
柿沼貴之; 菊池智大; 菅沼洸一; 石川良; 上野啓司; 白井肇
Volume：2013.1, First page：3517, Last page：3517, Mar. 2013
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2013.1.0_3517
DOI ID：10.11470/jsapmeeting.2013.1.0_3517, eISSN：2436-7613

Agナノワイヤーand MWCNTsを用いたc-Si/PEDOT:PSS接合太陽電池　　　　　　　　　　　　　　　
渡邊郁弥; 星野彩; 石川良; 上野啓司; 白井肇
Volume：2013.1, First page：2484, Last page：2484, Mar. 2013
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2013.1.0_2484
DOI ID：10.11470/jsapmeeting.2013.1.0_2484, eISSN：2436-7613

酸化グラフェンをテンプレートに利用した薄膜SiおよびAZO剥離転写　　　　　　　　　　　　　　　
渡辺恭平; 越野秀人; 石川良; 上野啓司; 白井肇
Volume：2013.1, First page：3450, Last page：3450, Mar. 2013
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2013.1.0_3450
DOI ID：10.11470/jsapmeeting.2013.1.0_3450, eISSN：2436-7613

Si ナノワイヤ配列の形成と PEDOT:PSS の埋め込みプロセス　　　　　　　　　　　　　　　
今村教嗣; 石川良; 上野啓司; 白井肇
Volume：2013.1, First page：2544, Last page：2544, Mar. 2013
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2013.1.0_2544
DOI ID：10.11470/jsapmeeting.2013.1.0_2544, eISSN：2436-7613

可溶性酸化グラフェンを基盤材料とした結晶Si系太陽電池　　　　　　　　　　　　　　　
星野彩; 渡邊郁弥; 石川良; 上野啓司; 白井肇
Volume：2013.1, First page：3484, Last page：3484, Mar. 2013
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2013.1.0_3484
DOI ID：10.11470/jsapmeeting.2013.1.0_3484, eISSN：2436-7613

MoO3添加PEDOT:PSSの微細構造と結晶Si系太陽電池　　　　　　　　　　　　　　　
劉奇明; 石川良; 上野啓司; 白井肇
Volume：2013.1, First page：2485, Last page：2485, Mar. 2013
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2013.1.0_2485
DOI ID：10.11470/jsapmeeting.2013.1.0_2485, eISSN：2436-7613

PEDOT:PSSの光学異方性と結晶Si接合系太陽電池　　　　　　　　　　　　　　　
石川恭兵; 日當大我; 石川良; 上野啓司; 白井肇
Volume：2013.1, First page：2543, Last page：2543, Mar. 2013
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2013.1.0_2543
DOI ID：10.11470/jsapmeeting.2013.1.0_2543, eISSN：2436-7613

酸化亜鉛ナノ粒子を電子輸送層とする逆型有機薄膜太陽電池(2)　　　　　　　　　　　　　　　
石川良; 白井肇; 上野啓司
Volume：2013.1, First page：2541, Last page：2541, Mar. 2013
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2013.1.0_2541
DOI ID：10.11470/jsapmeeting.2013.1.0_2541, eISSN：2436-7613

Efficient Organic Photovoltaic Cells Using MoO3 Hole-Transporting Layers Prepared by Simple Spin-Cast of Its Dispersion Solution in Methanol　　　　　　　　　　　　　　　
Mayuko Kishi; Yosuke Kubo; Ryo Ishikawa; Hajime Shirai; Keiji Ueno
JAPANESE JOURNAL OF APPLIED PHYSICS, Volume：52, Number：2, Feb. 2013
English, Scientific journal
DOI：https://doi.org/10.7567/JJAP.52.020202
DOI ID：10.7567/JJAP.52.020202, ISSN：0021-4922, SCOPUS ID：84874145843, Web of Science ID：WOS:000314466800002

Green-tea modified multiwalled carbon nanotubes for efficient poly(3,4-ethylenedioxythiophene):poly(stylenesulfonate)/n-silicon hybrid solar cell　　　　　　　　　　　　　　　
Ishwor Khatri; Zeguo Tang; Qiming Liu; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
APPLIED PHYSICS LETTERS, Volume：102, Number：6, Feb. 2013
English, Scientific journal
DOI：https://doi.org/10.1063/1.4792691
DOI ID：10.1063/1.4792691, ISSN：0003-6951, SCOPUS ID：84874255755, Web of Science ID：WOS:000315053300101

High-performance top-gated monolayer SnS2 field-effect transistors and their integrated logic circuits　　　　　　　　　　　　　　　
H. S. Song; S. L. Li; L. Gao; Y. Xu; K. Ueno; J. Tang; Y. B. Cheng; K. Tsukagoshi
NANOSCALE, Volume：5, Number：20, First page：9666, Last page：9670, 2013
English, Scientific journal
DOI：https://doi.org/10.1039/c3nr01899g
DOI ID：10.1039/c3nr01899g, ISSN：2040-3364, eISSN：2040-3372, SCOPUS ID：84884862198, Web of Science ID：WOS:000325005500032

Top-Contacted Organic Field-Effect Transistors with Graphene Electrodes Prepared by Laminate Transfer Method　　　　　　　　　　　　　　　
Koichi Suganuma; Takuya Gotou; Keiji Ueno
APPLIED PHYSICS EXPRESS, Volume：5, Number：12, Dec. 2012
English, Scientific journal
DOI：https://doi.org/10.1143/APEX.5.125104
DOI ID：10.1143/APEX.5.125104, ISSN：1882-0778, SCOPUS ID：84871267851, Web of Science ID：WOS:000312000800021

Increased Organic Photovoltaic Cell Efficiency by Incorporating a Nonionic Fluorinated Surfactant Cathode Interlayer　　　　　　　　　　　　　　　
Ryo Ishikawa; Hajime Shirai; Keiji Ueno
APPLIED PHYSICS EXPRESS, Volume：5, Number：12, Dec. 2012
English, Scientific journal
DOI：https://doi.org/10.1143/APEX.5.121601
DOI ID：10.1143/APEX.5.121601, ISSN：1882-0778, SCOPUS ID：84871261851, Web of Science ID：WOS:000312000800003

Crystalline Silicon/Graphene Oxide Hybrid Junction Solar Cells　　　　　　　　　　　　　　　
Qiming Liu; Fumiya Wanatabe; Aya Hoshino; Ryo Ishikawa; Takuya Gotou; Keiji Ueno; Hajime Shirai
JAPANESE JOURNAL OF APPLIED PHYSICS, Volume：51, Number：10, Oct. 2012
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.51.10NE22
DOI ID：10.1143/JJAP.51.10NE22, ISSN：0021-4922, eISSN：1347-4065, SCOPUS ID：84869120444, Web of Science ID：WOS:000310707800114

Electrospray-Deposited Poly(3,4-ethylenedioxythiophene):Poly(styrene sulfonate) for Poly(3-hexylthiophene):Phenyl-C-61-Butyric Acid Methyl Ester Photovoltaic Cells　　　　　　　　　　　　　　　
Taiga Hiate; Tomohisa Ino; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
JAPANESE JOURNAL OF APPLIED PHYSICS, Volume：51, Number：10, Oct. 2012
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.51.10NE30
DOI ID：10.1143/JJAP.51.10NE30, ISSN：0021-4922, eISSN：1347-4065, SCOPUS ID：84869115119, Web of Science ID：WOS:000310707800122

Real-time ellipsometric characterization of the initial growth stage of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) films by electrospray deposition using N,N-dimethylformamide solvent solution　　　　　　　　　　　　　　　
Tomohisa Ino; Taiga Hiate; Takeshi Fukuda; Keiji Ueno; Hajime Shirai
JOURNAL OF NON-CRYSTALLINE SOLIDS, Volume：358, Number：17, First page：2520, Last page：2524, Sep. 2012
English, Scientific journal
DOI：https://doi.org/10.1016/j.jnoncrysol.2012.01.055
DOI ID：10.1016/j.jnoncrysol.2012.01.055, ISSN：0022-3093, eISSN：1873-4812, SCOPUS ID：84865702464, Web of Science ID：WOS:000310394700142

酸化グラフェン(GO)薄片のC₂H₂/Arプラズマ処理による低抵抗化　　　　　　　　　　　　　　　
渡邊郁弥; 星野彩; 菅沼洸一; 石川良; 上野啓司; 白井肇
Volume：2012.2, First page：3603, Last page：3603, Aug. 2012
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2012.2.0_3603
DOI ID：10.11470/jsapmeeting.2012.2.0_3603, eISSN：2436-7613

Siテクスチャー上の結晶Si/PEDOT:PSS接合太陽電池　　　　　　　　　　　　　　　
宮内直人; 今村教嗣; 劉奇明; 石川良; 上野啓司; 白井肇
Volume：2012.2, First page：2602, Last page：2602, Aug. 2012
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2012.2.0_2602
DOI ID：10.11470/jsapmeeting.2012.2.0_2602, eISSN：2436-7613

結晶Ｓｉ上の霧化塗布(CMD)法によるＰＥＤＯＴ：ＰＳＳ製膜　　　　　　　　　　　　　　　
今村教嗣; 石川良; 上野啓司; 白井肇
Volume：2012.2, First page：2600, Last page：2600, Aug. 2012
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2012.2.0_2600
DOI ID：10.11470/jsapmeeting.2012.2.0_2600, eISSN：2436-7613

フッ素系界面活性剤層の挿入による有機薄膜太陽電池の性能向上　　　　　　　　　　　　　　　
石川良; 白井肇; 上野啓司
Volume：2012.2, First page：2568, Last page：2568, Aug. 2012
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2012.2.0_2568
DOI ID：10.11470/jsapmeeting.2012.2.0_2568, eISSN：2436-7613

Electrospray Deposition of Poly(3-hexylthiophene) Films for Crystalline Silicon/Organic Hybrid Junction Solar Cells　　　　　　　　　　　　　　　
Tomohisa Ino; Masahiro Ono; Naoto Miyauchi; Qiming Liu; Zeguo Tang; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
JAPANESE JOURNAL OF APPLIED PHYSICS, Volume：51, Number：6, Jun. 2012
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.51.061602
DOI ID：10.1143/JJAP.51.061602, ISSN：0021-4922, eISSN：1347-4065, SCOPUS ID：84863329516, Web of Science ID：WOS:000305135200010

Highly efficient crystalline silicon/Zonyl fluorosurfactant-treated organic heterojunction solar cells　　　　　　　　　　　　　　　
Qiming Liu; Masahiro Ono; Zeguo Tang; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
APPLIED PHYSICS LETTERS, Volume：100, Number：18, Apr. 2012
English, Scientific journal
DOI：https://doi.org/10.1063/1.4709615
DOI ID：10.1063/1.4709615, ISSN：0003-6951, eISSN：1077-3118, SCOPUS ID：84862542199, Web of Science ID：WOS:000303598600067

Efficient Crystalline Si/Poly(ethylene dioxythiophene): Poly(styrene sulfonate): Graphene Oxide Composite Heterojunction Solar Cells　　　　　　　　　　　　　　　
Masahiro Ono; Zeguo Tang; Ryo Ishikawa; Takuya Gotou; Keiji Ueno; Hajime Shirai
APPLIED PHYSICS EXPRESS, Volume：5, Number：3, Mar. 2012
English, Scientific journal
DOI：https://doi.org/10.1143/APEX.5.032301
DOI ID：10.1143/APEX.5.032301, ISSN：1882-0778, eISSN：1882-0786, SCOPUS ID：84858675339, Web of Science ID：WOS:000301344400014

酸化グラフェンを正孔輸送層とする有機薄膜太陽電池素子のUV-O₃処理による性能向上　　　　　　　　　　　　　　　
久保洋輔; 石川良; 白井肇; 後藤拓也; 上野啓司
Volume：2012.1, First page：2772, Last page：2772, Feb. 2012
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2012.1.0_2772
DOI ID：10.11470/jsapmeeting.2012.1.0_2772, eISSN：2436-7613

結晶Si/PEDOT:PSS:GOへテロ接合素子のキャリア輸送特性　　　　　　　　　　　　　　　
唐澤国; 小野正浩; 猪野智久; 石川良; 上野啓司; 白井肇
Volume：2012.1, First page：427, Last page：427, Feb. 2012
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2012.1.0_427
DOI ID：10.11470/jsapmeeting.2012.1.0_427, eISSN：2436-7613

Ionic liquid-mediated epitaxy of high-quality C-60 crystallites in a vacuum　　　　　　　　　　　　　　　
Yoko Takeyama; Shingo Maruyama; Hiroki Taniguchi; Mitsuru Itoh; Keiji Ueno; Yuji Matsumoto
CRYSTENGCOMM, Volume：14, Number：15, First page：4939, Last page：4945, 2012
English, Scientific journal
DOI：https://doi.org/10.1039/c2ce25163a
DOI ID：10.1039/c2ce25163a, ISSN：1466-8033, SCOPUS ID：84863705273, Web of Science ID：WOS:000305999500009

Chemical mist deposition of graphene oxide and PEDOT:PSS films for crystalline Si/organic heterojunction solar cells　　　　　　　　　　　　　　　
Ishwor Khatri; Takashi Imamura; Akira Uehara; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 9, NO 10-11, Volume：9, Number：10-11, First page：2134, Last page：2137, 2012
English, International conference proceedings
DOI：https://doi.org/10.1002/pssc.201200132
DOI ID：10.1002/pssc.201200132, ISSN：1862-6351, SCOPUS ID：84867947008, Web of Science ID：WOS:000314688000059

Efficient crystalline Si/organic hybrid heterojunction solar cells　　　　　　　　　　　　　　　
Qiming Liu; Ishwor Khatri; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 9, NO 10-11, Volume：9, Number：10-11, First page：2101, Last page：2106, 2012
English, International conference proceedings
DOI：https://doi.org/10.1002/pssc.201200131
DOI ID：10.1002/pssc.201200131, ISSN：1862-6351, SCOPUS ID：84867952936, Web of Science ID：WOS:000314688000051

Poly(3-hexylthiophene) films by electrospray deposition for crystalline silicon/organic hybrid junction solar cells　　　　　　　　　　　　　　　
Taiga Hiate; Naoto Miyauchi; Zeguo Tang; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 9, NO 10-11, Volume：9, Number：10-11, First page：2071, Last page：2074, 2012
English, International conference proceedings
DOI：https://doi.org/10.1002/pssc.201200129
DOI ID：10.1002/pssc.201200129, ISSN：1862-6351, SCOPUS ID：84867942138, Web of Science ID：WOS:000314688000044

Optical properties and carrier transport in c-Si/conductive PEDOT:PSS(GO) composite heterojunctions　　　　　　　　　　　　　　　
Zeguo Tang; Qiming Liu; Ishwor Khatri; Ryo Ishikawa; Keiji Ueno; Hajime Shirai
PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 9, NO 10-11, Volume：9, Number：10-11, First page：2075, Last page：2078, 2012
English, International conference proceedings
DOI：https://doi.org/10.1002/pssc.201200130
DOI ID：10.1002/pssc.201200130, ISSN：1862-6351, SCOPUS ID：84867935974, Web of Science ID：WOS:000314688000045

Solution Processed Graphene Transparent Conductive Film
Keiji Ueno
2012 19TH INTERNATIONAL WORKSHOP ON ACTIVE-MATRIX FLATPANEL DISPLAYS AND DEVICES (AM-FPD): TFT TECHNOLOGIES AND FPD MATERIALS, First page：49, Last page：52, 2012
English, International conference proceedings
SCOPUS ID：84867908879, Web of Science ID：WOS:000326894500013

Surface Modification of Poly(3,4-ethylene dioxthiophene):Poly(styrene sulfonic acid) (PEDOT:PSS) Films by Atmospheric-Pressure Argon Plasma for Organic Thin-Film Solar Cells　　　　　　　　　　　　　　　
Tomohisa Mo; Tatsuya Hayashi; Takeshi Fukuda; Keiji Ueno; Hajime Shirai
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY, Volume：11, Number：9, First page：8035, Last page：8039, Sep. 2011
English, Scientific journal
DOI：https://doi.org/10.1166/jnn.2011.5065
DOI ID：10.1166/jnn.2011.5065, ISSN：1533-4880, eISSN：1533-4899, SCOPUS ID：84856850669, Web of Science ID：WOS:000296209900070

Real-Time Ellipsometric Characterization of the Initial Growth Stage of Poly(3,4-ethylene dioxythiophene): Poly(styrene sulfonic acid) Films by Electrospray Deposition　　　　　　　　　　　　　　　
Tomohisa Ino; Takashi Asano; Takeshi Fukuda; Keiji Ueno; Hajime Shirai
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY, Volume：11, Number：9, First page：8030, Last page：8034, Sep. 2011
English, Scientific journal
DOI：https://doi.org/10.1166/jnn.2011.5064
DOI ID：10.1166/jnn.2011.5064, ISSN：1533-4880, eISSN：1533-4899, SCOPUS ID：84856894365, Web of Science ID：WOS:000296209900069

有機薄膜太陽電池の光電変換層へのグラフェンドーピング効果（2）　　　　　　　　　　　　　　　
石川良; 後藤拓也; 白井肇; 上野啓司
Volume：2011.2, First page：2161, Last page：2161, Aug. 2011
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2011.2.0_2161
DOI ID：10.11470/jsapmeeting.2011.2.0_2161, eISSN：2436-7613

Depth Profile Characterization of Spin-Coated Poly(3,4-ethylenedioxythiophene):Poly(styrene sulfonic acid) Films for Thin-Film Solar Cells during Argon Plasma Etching by Spectroscopic Ellipsometry　　　　　　　　　　　　　　　
Tomohisa Ino; Tatsuya Hayashi; Keiji Ueno; Hajime Shirai
JAPANESE JOURNAL OF APPLIED PHYSICS, Volume：50, Number：8, Aug. 2011
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.50.08JG02
DOI ID：10.1143/JJAP.50.08JG02, ISSN：0021-4922, eISSN：1347-4065, SCOPUS ID：80051969829, Web of Science ID：WOS:000294339500045

Real-Time Ellipsometric Characterization of Initial Growth Stage of Poly(3,4-ethylene dioxythiophene):Poly(styrene sulfonic acid) Films by Electrospray Deposition　　　　　　　　　　　　　　　
Tomohisa Ino; Takashi Asano; Takeshi Fukuda; Keiji Ueno; Hajime Shirai
JAPANESE JOURNAL OF APPLIED PHYSICS, Volume：50, Number：8, Aug. 2011
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.50.081603
DOI ID：10.1143/JJAP.50.081603, ISSN：0021-4922, eISSN：1347-4065, SCOPUS ID：80051974504, Web of Science ID：WOS:000294336600032

Atmospheric-pressure argon plasma etching of spin-coated 3,4-polyethylenedioxythiophene:polystyrenesulfonic acid (PEDOT:PSS) films for cupper phtalocyanine (CuPc)/C-60 heterojunction thin-film solar cells　　　　　　　　　　　　　　　
Tomohisa Ino; Tatsuya Hayashi; Keiji Ueno; Hajime Shirai
THIN SOLID FILMS, Volume：519, Number：20, First page：6834, Last page：6839, Aug. 2011
English, Scientific journal
DOI：https://doi.org/10.1016/j.tsf.2011.04.042
DOI ID：10.1016/j.tsf.2011.04.042, ISSN：0040-6090, SCOPUS ID：80051547199, Web of Science ID：WOS:000294790900043

Bulk heterojunction organic photovoltaic cell fabricated by the electrospray deposition method using mixed organic solvent　　　　　　　　　　　　　　　
Takeshi Fukuda; Kenji Takagi; Takashi Asano; Zentaro Honda; Norihiko Kamata; Keiji Ueno; Hajime Shirai; Jungmyoung Ju; Yutaka Yamagata; Yusuke Tajima
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS, Volume：5, Number：7, First page：229, Last page：231, Jul. 2011
English, Scientific journal
DOI：https://doi.org/10.1002/pssr.201105232
DOI ID：10.1002/pssr.201105232, ISSN：1862-6254, SCOPUS ID：79959962240, Web of Science ID：WOS:000293595100005

Efficient Organic Photovoltaic Cells Using Hole-Transporting MoO3 Buffer Layers Converted from Solution-Processed MoS2 Films　　　　　　　　　　　　　　　
Shogo Kato; Ryo Ishikawa; Yosuke Kubo; Hajime Shirai; Keiji Ueno
JAPANESE JOURNAL OF APPLIED PHYSICS, Volume：50, Number：7, Jul. 2011
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.50.071604
DOI ID：10.1143/JJAP.50.071604, ISSN：0021-4922, SCOPUS ID：79960694667, Web of Science ID：WOS:000292878200045

DMSOドープPEDOT:PSSをTCOに用いたCuPc/C60へテロ接合型太陽電池　　　　　　　　　　　　　　　
村松義之; 林達也; 猪野智久; 石川良; 上野啓司
Volume：2011.1, First page：2802, Last page：2802, Mar. 2011
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2011.1.0_2802
DOI ID：10.11470/jsapmeeting.2011.1.0_2802, eISSN：2436-7613

有機薄膜太陽電池の光電変換層へのグラフェンドーピング効果　　　　　　　　　　　　　　　
石川良; 後藤拓也; 白井肇; 上野啓司
Volume：2011.1, First page：2781, Last page：2781, Mar. 2011
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2011.1.0_2781
DOI ID：10.11470/jsapmeeting.2011.1.0_2781, eISSN：2436-7613

Fabrication of Transparent and Flexible Organic Field-Effect Transistors with Solution-Processed Graphene Source-Drain and Gate Electrodes　　　　　　　　　　　　　　　
Koichi Suganuma; Shunichiro Watanabe; Takuya Gotou; Keiji Ueno
APPLIED PHYSICS EXPRESS, Volume：4, Number：2, Feb. 2011
English, Scientific journal
DOI：https://doi.org/10.1143/APEX.4.021603
DOI ID：10.1143/APEX.4.021603, ISSN：1882-0778, SCOPUS ID：79951588162, Web of Science ID：WOS:000287378800011

Depth profile characterization of spin-coated poly(3,4-ethylenedioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSS) films by spectroscopic ellipsometry　　　　　　　　　　　　　　　
Tomohisa Ino; Tatsuya Hayashi; Takeshi Fukuda; Keiji Ueno; Hajime Shirai
PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 8, NO 10, Volume：8, Number：10, First page：3025, Last page：3028, 2011
English, International conference proceedings
DOI：https://doi.org/10.1002/pssc.201001218
DOI ID：10.1002/pssc.201001218, ISSN：1862-6351, SCOPUS ID：80053599990, Web of Science ID：WOS:000301591500013

酸化グラフェンを正孔輸送層に用いたCuPc/C₆₀太陽電池　　　　　　　　　　　　　　　
林達也; 猪野智久; 村松義之; 久保洋輔; 石川良; 後藤拓也; 上野啓司; 白井肇
Volume：2010.2, First page：2115, Last page：2115, Aug. 2010
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2010.2.0_2115
DOI ID：10.11470/jsapmeeting.2010.2.0_2115, eISSN：2436-7613

CuPc/C₆₀太陽電池素子性能におけるPEDOT:PSSの低温プラズマ処理効果　　　　　　　　　　　　　　　
猪野智久; 林達也; 石川良; 菅沼洸一; 上野啓司; 白井肇
Volume：2010.2, First page：2130, Last page：2130, Aug. 2010
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2010.2.0_2130
DOI ID：10.11470/jsapmeeting.2010.2.0_2130, eISSN：2436-7613

化学的薄片剥離により形成したグラフェン薄膜の電子エネルギー損失分光測定(2):還元状態の深さ方向解析　　　　　　　　　　　　　　　
石川良; 吉田雅史; 斉木幸一朗; 後藤拓也; 上野啓司
Volume：2010.1, First page：3784, Last page：3784, Mar. 2010
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2010.1.0_3784
DOI ID：10.11470/jsapmeeting.2010.1.0_3784, eISSN：2436-7613

プラズマ処理PEDOT:PSS基板上 CuPc/C₆₀太陽電池　　　　　　　　　　　　　　　
林達也; 猪野智久; 白井肇; 上野啓司; 石川良
Volume：2010.1, First page：2383, Last page：2383, Mar. 2010
Japanese
DOI：https://doi.org/10.11470/jsapmeeting.2010.1.0_2383
DOI ID：10.11470/jsapmeeting.2010.1.0_2383, eISSN：2436-7613

Origin of the ambipolar operation of a pentacene field-effect transistor fabricated on a poly(vinyl alcohol)-coated Ta2O5 gate dielectric with Au source/drain electrodes　　　　　　　　　　　　　　　
Satoko Takebayashi; Shigeomi Abe; Koichiro Saiki; Keiji Ueno
APPLIED PHYSICS LETTERS, Volume：94, Number：8, Feb. 2009
English, Scientific journal
DOI：https://doi.org/10.1063/1.3089692
DOI ID：10.1063/1.3089692, ISSN：0003-6951, SCOPUS ID：61349094005, Web of Science ID：WOS:000263804400079

27aYH-8 Reduction of ultra thin graphene oxide films and its electric properties　　　　　　　　　　　　　　　
小幡誠司; 佐藤裕樹; 白石淳子; 服部功三; 吉田雅史; 上野啓司; 斉木幸一朗
Meeting Abstracts of the Physical Society of Japan, Volume：64.1.4, First page：812, 2009
The Physical Society of Japan, Japanese
DOI：https://doi.org/10.11316/jpsgaiyo.64.1.4.0_812_3
DOI ID：10.11316/jpsgaiyo.64.1.4.0_812_3, eISSN：2189-0803, CiNii Articles ID：110007372761

Step-bunched Bi-terminated Si(111) surfaces as a nanoscale orientation template for quasisingle crystalline epitaxial growth of thin film phase pentacene　　　　　　　　　　　　　　　
Toshihiro Shimada; Manabu Ohtomo; Tadamasa Suzuki; Tetsuya Hasegawa; Keiji Ueno; Susumu Ikeda; Koichiro Saiki; Miho Sasaki; Katsuhiko Inaba
APPLIED PHYSICS LETTERS, Volume：93, Number：22, First page：223303, Dec. 2008
English, Scientific journal
DOI：https://doi.org/10.1063/1.3040309
DOI ID：10.1063/1.3040309, ISSN：0003-6951, eISSN：1077-3118, CiNii Articles ID：80020068364, SCOPUS ID：57349166529, Web of Science ID：WOS:000261430600074

Nucleation on the substrate surfaces during liquid flux-mediated vacuum deposition of rubrene　　　　　　　　　　　　　　　
Toshihiro Shimada; Yui Ishii; Keiji Ueno; Tetsuya Hasegawa
JOURNAL OF CRYSTAL GROWTH, Volume：311, Number：1, First page：163, Last page：166, Dec. 2008
English, Scientific journal
DOI：https://doi.org/10.1016/j.jcrysgro.2008.10.096
DOI ID：10.1016/j.jcrysgro.2008.10.096, ISSN：0022-0248, SCOPUS ID：57649215856, Web of Science ID：WOS:000262796500032

Nanotransfer of the Polythiophene Molecular Alignment onto the Step-Bunched Vicinal Si(111) Substrate　　　　　　　　　　　　　　　
Ryo Onoki; Genki Yoshikawa; Yuki Tsuruma; Susumu Ikeda; Koichiro Saiki; Keiji Ueno
LANGMUIR, Volume：24, Number：20, First page：11605, Last page：11610, Oct. 2008
English, Scientific journal
DOI：https://doi.org/10.1021/la8016722
DOI ID：10.1021/la8016722, ISSN：0743-7463, CiNii Articles ID：80019928706, PubMed ID：18778089, SCOPUS ID：55549094431, Web of Science ID：WOS:000260049300039

Molecular layer-by-layer growth of C-60 thin films by continuous-wave infrared laser deposition　　　　　　　　　　　　　　　
Seiichiro Yaginuma; Kenji Itaka; Masamitsu Haemori; Masao Katayama; Keiji Ueno; Tsuyoshi Ohnishi; Mikk Lippmaa; Yuji Matsumoto; Hideomi Koinuma
APPLIED PHYSICS EXPRESS, Volume：1, Number：1, First page：015005-1-015005-3, Jan. 2008
English, Scientific journal
DOI：https://doi.org/10.1143/APEX.1.015005
DOI ID：10.1143/APEX.1.015005, ISSN：1882-0778, SCOPUS ID：57049104631, Web of Science ID：WOS:000255452500034

Effect of organic buffer layer on performance of pentacene field-effect transistor fabricated on natural mica gate dielectric　　　　　　　　　　　　　　　
Akira Matsumoto; Ryo Onoki; Susumu Ikeda; Koichiro Saiki; Keiji Ueno
JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS, Volume：46, Number：36-40, First page：L913, Last page：L916, Oct. 2007
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.46.L913
DOI ID：10.1143/JJAP.46.L913, ISSN：0021-4922, CiNii Articles ID：120001370972, SCOPUS ID：36048995921, Web of Science ID：WOS:000250535600017

Orientation control of standing epitaxial pentacene monolayers using surface steps and inplane band dispersion analysis by angle resolved photoelectron spectroscopy
Tadamasa Suzuki; Toshihiro Shimada; Keiji Ueno; Susumu Ikeda; Koichiro Saiki; Tetsuya Hasegawa
Materials Research Society Symposium Proceedings, Volume：965, First page：380, Last page：385, Dec. 2006
Springer Science and Business Media LLC, Scientific journal
DOI：https://doi.org/10.1557/proc-0965-s06-19
DOI ID：10.1557/proc-0965-s06-19, ISSN：0272-9172, eISSN：1946-4274, SCOPUS ID：40949147723

Structure of organic thin films grown on surface-modified tantalum oxide　　　　　　　　　　　　　　　
Ryo Onoki; Shigeomi Abe; Keiji Ueno; Hiroo Nakahara; Koichiro Saiki
CHEMISTRY LETTERS, Volume：35, Number：7, First page：746, Last page：747, Jul. 2006
English, Scientific journal
DOI：https://doi.org/10.1246/cl.2006.746
DOI ID：10.1246/cl.2006.746, ISSN：0366-7022, eISSN：1348-0715, SCOPUS ID：33749340028, Web of Science ID：WOS:000240439900026

In-situ measurement of molecular orientation of the pentacene ultrathin films grown on SiO2 substrates　　　　　　　　　　　　　　　
Genki Yoshikawa; Tetsuhiko Miyadera; Ryo Onoki; Keiji Ueno; Ikuyo Nakai; Shiro Entani; Susumu Ikeda; Dong Guo; Manabu Kiguchi; Hiroshi Kondoh; Toshiaki Ohta; Koichiro Saiki
SURFACE SCIENCE, Volume：600, Number：12, First page：2518, Last page：2522, Jun. 2006
English, Scientific journal
DOI：https://doi.org/10.1016/j.susc.2006.04.012
DOI ID：10.1016/j.susc.2006.04.012, ISSN：0039-6028, CiNii Articles ID：120001370595, SCOPUS ID：33744992043, Web of Science ID：WOS:000238893800016

Anisotropic polymerization of a long-chain diacetylene derivative Langmuir-Blodgett film on a step-bunched SiO2/Si surface　　　　　　　　　　　　　　　
R Onoki; K Ueno; H Nakahara; G Yoshikawa; S Ikeda; S Entani; T Miyadera; Nakai, I; H Kondoh; T Ohta; M Kiguchi; K Saiki
LANGMUIR, Volume：22, Number：13, First page：5742, Last page：5747, Jun. 2006
English, Scientific journal
DOI：https://doi.org/10.1021/la060482d
DOI ID：10.1021/la060482d, ISSN：0743-7463, SCOPUS ID：33745746059, Web of Science ID：WOS:000238217000039

Fabrication of an organic field-effect transistor on a mica gate dielectric　　　　　　　　　　　　　　　
Akira Matsumoto; Ryo Onoki; Keiji Ueno; Susumu Ikeda; Koichiro Saiki
CHEMISTRY LETTERS, Volume：35, Number：4, First page：354, Last page：355, Apr. 2006
English, Scientific journal
DOI：https://doi.org/10.1246/cl.2006.354
DOI ID：10.1246/cl.2006.354, ISSN：0366-7022, eISSN：1348-0715, SCOPUS ID：33745840149, Web of Science ID：WOS:000237721500005

Anodization of electrolytically polished Ta surfaces for enhancement of carrier injection into organic field-effect transistors　　　　　　　　　　　　　　　
K Ueno; S Abe; R Onoki; K Saiki
JOURNAL OF APPLIED PHYSICS, Volume：98, Number：11, First page：114503-1-114503-5, Dec. 2005
English, Scientific journal
DOI：https://doi.org/10.1063/1.2138807
DOI ID：10.1063/1.2138807, ISSN：0021-8979, eISSN：1089-7550, SCOPUS ID：29144535658, Web of Science ID：WOS:000234119600088

Bulk-like pentacene epitaxial films on hydrogen-terminated Si(111)　　　　　　　　　　　　　　　
T Shimada; H Nogawa; T Hasegawa; R Okada; H Ichikawa; K Ueno; K Saiki
APPLIED PHYSICS LETTERS, Volume：87, Number：6, First page：061917, Aug. 2005
English, Scientific journal
DOI：https://doi.org/10.1063/1.2008371
DOI ID：10.1063/1.2008371, ISSN：0003-6951, eISSN：1077-3118, SCOPUS ID：23944444818, Web of Science ID：WOS:000231016900031

26pXC-7 Direction-controlled polymerization and NEXAFS analysis of a long-chain diacetylene derivative LB film　　　　　　　　　　　　　　　
Onoki R.; Ueno K.; Nakahara H.; Yoshikawa G.; Ikeda S.; Kiguchi M.; Nakai I.; Kondoh H.; Ohta T.; Saiki K.
Meeting Abstracts of the Physical Society of Japan, Volume：60.1.4, First page：870, 2005
The Physical Society of Japan, Japanese
DOI：https://doi.org/10.11316/jpsgaiyo.60.1.4.0_870_3
DOI ID：10.11316/jpsgaiyo.60.1.4.0_870_3, eISSN：2189-0803, CiNii Articles ID：110004537383

Morphological change of C60 monolayer epitaxial films under photoexcitation　　　　　　　　　　　　　　　
Y. Yamamoto; H. Ichikawa; K. Ueno; A. Koma; K. Saiki; T. Shimada
Physical Review B - Condensed Matter and Materials Physics, Volume：70, Number：15, First page：1, Last page：155415, Oct. 2004, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1103/PhysRevB.70.155415
DOI ID：10.1103/PhysRevB.70.155415, ISSN：0163-1829, SCOPUS ID：37649031320

Methyl-terminated Si(111) surface as the ultra thin protection layer to fabricate position-controlled alkyl SAMs by using atomic force microscope anodic oxidation　　　　　　　　　　　　　　　
R Okada; T Miyadera; T Shimada; A Koma; K Ueno; K Saiki
SURFACE SCIENCE, Volume：552, Number：1-3, First page：46, Last page：52, Mar. 2004
English, Scientific journal
DOI：https://doi.org/10.1016/j.susc.2004.01.026
DOI ID：10.1016/j.susc.2004.01.026, ISSN：0039-6028, eISSN：1879-2758, CiNii Articles ID：80016549565, SCOPUS ID：1342264254, Web of Science ID：WOS:000220123000009

Scanning tunneling microscopy and spectroscopy study of LiBr/Si(001) heterostructure　　　　　　　　　　　　　　　
M Katayama; K Ueno; A Koma; M Kiguchi; K Saiki
JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS, Volume：43, Number：2A, First page：L203, Last page：L205, Feb. 2004
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.43L203
DOI ID：10.1143/JJAP.43L203, ISSN：0021-4922, CiNii Articles ID：150000012948, SCOPUS ID：1942475767, Web of Science ID：WOS:000220092900027

Accumulation and depletion layer thicknesses in organic field effect transistors　　　　　　　　　　　　　　　
M Kiguchi; M Nakayama; K Fujiwara; K Ueno; T Shimada; K Saiki
JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS, Volume：42, Number：12A, First page：L1408, Last page：L1410, Dec. 2003
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.42.L1408
DOI ID：10.1143/JJAP.42.L1408, ISSN：0021-4922, CiNii Articles ID：150000012372, SCOPUS ID：0742286297, Web of Science ID：WOS:000187509800002

Visible light photoemission and negative electron affinity of single-crystalline CsCl thin films　　　　　　　　　　　　　　　
G Yoshikawa; M Kiguchi; K Ueno; A Koma; K Saiki
SURFACE SCIENCE, Volume：544, Number：2-3, First page：220, Last page：226, Oct. 2003
English, Scientific journal
DOI：https://doi.org/10.1016/j.susc.2003.08.016
DOI ID：10.1016/j.susc.2003.08.016, ISSN：0039-6028, CiNii Articles ID：80016315513, SCOPUS ID：0141959022, Web of Science ID：WOS:000186017900015

Nano-scale anodic oxidation on a Si(111) surface terminated by bilayer-GaSe　　　　　　　　　　　　　　　
K Ueno; R Okada; K Saiki; A Koma
SURFACE SCIENCE, Volume：514, Number：1-3, First page：27, Last page：32, Aug. 2002
English, Scientific journal
DOI：https://doi.org/10.1016/S0039-6028(02)01603-5
DOI ID：10.1016/S0039-6028(02)01603-5, ISSN：0039-6028, eISSN：1879-2758, SCOPUS ID：0037055541, Web of Science ID：WOS:000177832500005

Fabrication of GaAs quantum dots on a bilayer-GaSe terminated Si(111) substrate　　　　　　　　　　　　　　　
上野啓司; 斉木幸一朗; 小間篤
JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS, Volume：40, Number：3B, First page：1888, Last page：1891, Dec. 2001
INSTITUTE OF PURE AND APPLIED PHYSICS, English
DOI：https://doi.org/10.1143/JJAP.40.1888
DOI ID：10.1143/JJAP.40.1888, ISSN：0021-4922, CiNii Articles ID：150000038119, CiNii Books ID：AA10457675, SCOPUS ID：0035267624

Electron-energy-loss spectroscopy of C-60 monolayer films on active and inactive surfaces　　　　　　　　　　　　　　　
K Iizumi; K Ueno; K Saiki; A Koma
APPLIED SURFACE SCIENCE, Volume：169, First page：142, Last page：146, Jan. 2001, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1016/S0169-4332(00)00740-6
DOI ID：10.1016/S0169-4332(00)00740-6, ISSN：0169-4332, Web of Science ID：WOS:000167087700028

Fabrication of compound-semiconductor quantum dots on a Si(111) substrate terminated by bilayer-GaSe　　　　　　　　　　　　　　　
K Ueno; K Saiki; A Koma
PROCEEDINGS OF THE 25TH INTERNATIONAL CONFERENCE ON THE PHYSICS OF SEMICONDUCTORS, PTS I AND II, Volume：87, First page：385, Last page：386, 2001, [Reviewed]
English, International conference proceedings
ISSN：0930-8989, Web of Science ID：WOS:000171592800177

Low-energy electron energy loss spectroscopy of monolayer and thick La@C-82 films grown on MOS2 substrates　　　　　　　　　　　　　　　
K Ueno; Y Uchino; K Iizumi; A Koma; K Saiki; Y Inada; K Nagai; Y Iwasa; T Mitani
NANONETWORK MATERIALS: FULLERENES, NANOTUBES AND RELATED SYSTEMS, Volume：590, First page：485, Last page：488, 2001, [Reviewed]
English, International conference proceedings
ISSN：0094-243X, Web of Science ID：WOS:000176150700115

Electron-energy-loss spectroscopy of KxC60 and K-halides: comparison in the K-3p excitation region　　　　　　　　　　　　　　　
K Ueno; Y Uchino; K Iizumi; K Saiki; A Koma
APPLIED SURFACE SCIENCE, Volume：169, First page：184, Last page：187, Jan. 2001
English, Scientific journal
DOI：https://doi.org/10.1016/S0169-4332(00)00729-7
DOI ID：10.1016/S0169-4332(00)00729-7, ISSN：0169-4332, CiNii Articles ID：120001370985, SCOPUS ID：18844471293, Web of Science ID：WOS:000167087700037

Investigation of the growth mechanism of an InSe epitaxial layer on a MoS2 substrate　　　　　　　　　　　　　　　
T Hayashi; K Ueno; K Saiki; A Koma
JOURNAL OF CRYSTAL GROWTH, Volume：219, Number：1-2, First page：115, Last page：122, Oct. 2000
English, Scientific journal
DOI：https://doi.org/10.1016/S0022-0248(00)00627-8
DOI ID：10.1016/S0022-0248(00)00627-8, ISSN：0022-0248, SCOPUS ID：0037743369, Web of Science ID：WOS:000089675700015

Highly sensitive reflection high-energy electron diffraction measurement by use of micro-channel imaging plate　　　　　　　　　　　　　　　
K Saiki; T Kono; K Ueno; A Koma
REVIEW OF SCIENTIFIC INSTRUMENTS, Volume：71, Number：9, First page：3478, Last page：3479, Sep. 2000
English, Scientific journal
DOI：https://doi.org/10.1063/1.1287625
DOI ID：10.1063/1.1287625, ISSN：0034-6748, CiNii Articles ID：120001370930, SCOPUS ID：0141916970, Web of Science ID：WOS:000089036700036

Electron energy loss spectroscopy of a La@C_<82> thin film.　　　　　　　　　　　　　　　
Uchino Y.; Ueno K.; Iizumi K.; Saiki K.; Koma A.; Inada Y.; Nagai K.; Iwasa Y.; Mitani T.
Meeting Abstracts of the Physical Society of Japan, Volume：55.1.4, First page：740, 2000
The Physical Society of Japan, Japanese
DOI：https://doi.org/10.11316/jpsgaiyo.55.1.4.0_740_2
DOI ID：10.11316/jpsgaiyo.55.1.4.0_740_2, eISSN：2189-0803, CiNii Articles ID：110001916237

Electron spectroscopy of Ga quantum dots fabricated on bilayer-GaSe.　　　　　　　　　　　　　　　
Nakahara T.; Ueno K.; Saiki K.; Koma A.
Meeting Abstracts of the Physical Society of Japan, Volume：55.2.4, First page：778, 2000
The Physical Society of Japan, Japanese
DOI：https://doi.org/10.11316/jpsgaiyo.55.2.4.0_778_2
DOI ID：10.11316/jpsgaiyo.55.2.4.0_778_2, eISSN：2189-0803, CiNii Articles ID：110002150713

Growth and characterization of Ga2Se3/GaAs(100) epitaxial thin films　　　　　　　　　　　　　　　
K Ueno; M Kawayama; ZR Dai; A Koma; FS Ohuchi
JOURNAL OF CRYSTAL GROWTH, Volume：207, Number：1-2, First page：69, Last page：76, Nov. 1999, [Reviewed]
English, Scientific journal
ISSN：0022-0248, eISSN：1873-5002, Web of Science ID：WOS:000083594900011

A Novel Method to Fabricate a Molecular Quantum Structure: Selective Growth of C60 on Layered Material Heterostructures　　　　　　　　　　　　　　　
Keiji Ueno; Kentaro Sasaki; Koichiro Saiki; Atsushi Koma
Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers, Volume：38, Number：1 B, First page：511, Last page：514, 1999
Japan Society of Applied Physics, English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.38.511
DOI ID：10.1143/JJAP.38.511, ISSN：0021-4922, CiNii Articles ID：110003955735, SCOPUS ID：0032621059

Van der Weals type buffer layers: epitaxial growth of the large lattice mismatch system CdS/InSe/H-Si(111)　　　　　　　　　　　　　　　
T Loher; K Ueno; A Koma
APPLIED SURFACE SCIENCE, Volume：130, First page：334, Last page：339, Jun. 1998, [Reviewed]
English, Scientific journal
ISSN：0169-4332, Web of Science ID：WOS:000074407600059

Fabrication of C(60) nanostructures by selective growth on GaSe/MoS(2) and InSe/MoS(2) heterostructure substrates　　　　　　　　　　　　　　　
K Ueno; K Sasaki; T Nakahara; A Koma
APPLIED SURFACE SCIENCE, Volume：130, First page：670, Last page：675, Jun. 1998
English, Scientific journal
DOI：https://doi.org/10.1016/S0169-4332(98)00136-6
DOI ID：10.1016/S0169-4332(98)00136-6, ISSN：0169-4332, CiNii Articles ID：120001370933, SCOPUS ID：17444440854, Web of Science ID：WOS:000074407600116

Nanostructure fabrication using selective growth on nanosize patterns drawn by a scanning probe microscope　　　　　　　　　　　　　　　
K Sasaki; K Ueno; A Koma
JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS, Volume：36, Number：6B, First page：4061, Last page：4064, Jun. 1997
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.36.4061
DOI ID：10.1143/JJAP.36.4061, ISSN：0021-4922, CiNii Articles ID：110003947120, SCOPUS ID：0004786354, Web of Science ID：WOS:000073628300065

Investigation of the growth mechanism of layered semiconductor GaSe　　　　　　　　　　　　　　　
K Ueno; N Takeda; K Sasaki; A Koma
APPLIED SURFACE SCIENCE, Volume：113, First page：38, Last page：42, Apr. 1997
English, Scientific journal
DOI：https://doi.org/10.1016/S0169-4332(96)00837-9
DOI ID：10.1016/S0169-4332(96)00837-9, ISSN：0169-4332, SCOPUS ID：0031547190, Web of Science ID：WOS:A1997WW85000008

Nanostructure fabrication by selective growth of molecular crystals on layered material substrates　　　　　　　　　　　　　　　
K Ueno; K Sasaki; N Takeda; K Saiki; A Koma
APPLIED PHYSICS LETTERS, Volume：70, Number：9, First page：1104, Last page：1106, Mar. 1997
English, Scientific journal
DOI：https://doi.org/10.1063/1.118498
DOI ID：10.1063/1.118498, ISSN：0003-6951, CiNii Articles ID：120001370929, SCOPUS ID：0343095886, Web of Science ID：WOS:A1997WL14700015

Preparation of GaS thin films by molecular beam epitaxy　　　　　　　　　　　　　　　
H Yamada; K Ueno; A Koma
JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS, Volume：35, Number：5A, First page：L568, Last page：L570, May 1996
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.35.L568
DOI ID：10.1143/JJAP.35.L568, ISSN：0021-4922, SCOPUS ID：0030142630, Web of Science ID：WOS:A1996UM42300012

SCANNING TUNNELING MICROSCOPE OBSERVATION OF THE METAL-ADSORBED LAYERED SEMICONDUCTOR SURFACES　　　　　　　　　　　　　　　
H ABE; K KATAOKA; K UENO; A KOMA
JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS, Volume：34, Number：6B, First page：3342, Last page：3345, Jun. 1995
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.34.3342
DOI ID：10.1143/JJAP.34.3342, ISSN：0021-4922, SCOPUS ID：0029327415, Web of Science ID：WOS:A1995RH68400007

VAN-DER-WAALS EPITAXY ON HYDROGEN-TERMINATED SI(111) SURFACES AND INVESTIGATION OF ITS GROWTH-MECHANISM BY ATOMIC-FORCE MICROSCOPE　　　　　　　　　　　　　　　
K UENO; M SAKURAI; A KOMA
JOURNAL OF CRYSTAL GROWTH, Volume：150, Number：1-4, First page：1180, Last page：1185, May 1995, [Reviewed]
English, Scientific journal
ISSN：0022-0248, Web of Science ID：WOS:A1995RD43300095

Substrate effects on the nucleation and growth of GaSe layers by van der Waals epitaxy　　　　　　　　　　　　　　　
LE Rumaner; JL Gray; FS Ohuchi; K Ueno; A Koma
STRUCTURE AND PROPERTIES OF MULTILAYERED THIN FILMS, Volume：382, First page：101, Last page：106, 1995, [Reviewed]
English, International conference proceedings
ISSN：0272-9172, Web of Science ID：WOS:A1995BE43P00016

HETEROEPITAXIAL GROWTH OF LAYERED GASE FILMS ON GAAS(001) SURFACES　　　　　　　　　　　　　　　
H ABE; K UENO; K SAIKI; A KOMA
JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS, Volume：32, Number：10A, First page：L1444, Last page：L1447, Oct. 1993, [Reviewed]
English, Scientific journal
ISSN：0021-4922, Web of Science ID：WOS:A1993MC04400023

Heteroepitaxial growth of layered semiconductor gase on a hydrogen-terminated si(111) surface
Kuang-Yu Liu; Keiji Ueno; Yasunori Fujikawa; Koichiro Saiki; Atsushi Koma
Japanese Journal of Applied Physics, Volume：32, Number：3 B, First page：L434, Last page：L437, 1993
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.32.L434
DOI ID：10.1143/JJAP.32.L434, ISSN：1347-4065, SCOPUS ID：0345497522

Hétéroépitaxial growth of layered gase films on gaas(Ool) surfaces
Hideki Abe; Keiji Ueno; Koichiro Saiki; Atsushi Koma
Japanese Journal of Applied Physics, Volume：32, Number：10 A, First page：1444, Last page：1447, 1993
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.32.L1444
DOI ID：10.1143/JJAP.32.L1444, ISSN：1347-4065, SCOPUS ID：0027677089

Heteroepitaxy of layered III-VI semiconductor GaSe on hydrogen-terminated Si(111) surfaces　　　　　　　　　　　　　　　
Keiji Ueno; Liu Kuang-Yu; Yasunori Fujikawa; Koichiro Saiki; Atsushi Koma
Conference on Solid State Devices and Materials, First page：680, Last page：682, Dec. 1992
SCOPUS ID：0026957774

HETEROEPITAXY OF LAYERED COMPOUND SEMICONDUCTOR GASE ONTO GAAS-SURFACES FOR VERY EFFECTIVE PASSIVATION OF NANOMETER STRUCTURES　　　　　　　　　　　　　　　
K UENO; H ABE; K SAIKI; A KOMA; H OIGAWA; Y NANNICHI
SURFACE SCIENCE, Volume：267, Number：1-3, First page：43, Last page：46, Apr. 1992
English, Scientific journal
DOI：https://doi.org/10.1016/0039-6028(92)91084-O
DOI ID：10.1016/0039-6028(92)91084-O, ISSN：0039-6028, SCOPUS ID：0026850793, Web of Science ID：WOS:A1992HM90100013

GROWTH OF MOSE2 THIN-FILMS WITH VANDERWAALS EPITAXY　　　　　　　　　　　　　　　
FS OHUCHI; T SHIMADA; BA PARKINSON; K UENO; A KOMA
JOURNAL OF CRYSTAL GROWTH, Volume：111, Number：1-4, First page：1033, Last page：1037, May 1991, [Reviewed]
English, Scientific journal
DOI：https://doi.org/10.1016/0022-0248(91)91127-V
DOI ID：10.1016/0022-0248(91)91127-V, ISSN：0022-0248, Web of Science ID：WOS:A1991FT19000191

HETEROEPITAXIAL GROWTH BY VANDERWAALS INTERACTION IN ONE-DIMENSIONAL, 2-DIMENSIONAL AND 3-DIMENSIONAL MATERIALS　　　　　　　　　　　　　　　
A KOMA; K UENO; K SAIKI
JOURNAL OF CRYSTAL GROWTH, Volume：111, Number：1-4, First page：1029, Last page：1032, May 1991
English, Scientific journal
DOI：https://doi.org/10.1016/0022-0248(91)91126-U
DOI ID：10.1016/0022-0248(91)91126-U, ISSN：0022-0248, SCOPUS ID：0026413337, Web of Science ID：WOS:A1991FT19000190

Heteroepitaxy of layered semiconductor gase on a gaas(III)b surface
Keiji Ueno; Hideki Abe; Koichiro Saiki; Atsushi Koma
Japanese Journal of Applied Physics, Volume：30, Number：8, First page：L1352, Last page：L1354, 1991
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.30.L1352
DOI ID：10.1143/JJAP.30.L1352, ISSN：1347-4065, SCOPUS ID：0026203505

EPITAXIAL-GROWTH OF TRANSITION-METAL DICHALCOGENIDES ON CLEAVED FACES OF MICA　　　　　　　　　　　　　　　
K UENO; K SAIKI; T SHIMADA; A KOMA
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS, Volume：8, Number：1, First page：68, Last page：72, Jan. 1990
English, Scientific journal
DOI：https://doi.org/10.1116/1.576983
DOI ID：10.1116/1.576983, ISSN：0734-2101, CiNii Articles ID：120001370926, SCOPUS ID：84967850146, Web of Science ID：WOS:A1990CL59400010

Heteroepitaxial growth of layered transition metal dichalcogenides on sulfur-terminated GaAs{111} surfaces　　　　　　　　　　　　　　　
Keiji Ueno; Toshihiro Shimada; Koichiro Saiki; Atsushi Koma
Applied Physics Letters, Volume：56, Number：4, First page：327, Last page：329, 1990
English, Scientific journal
DOI：https://doi.org/10.1063/1.102817
DOI ID：10.1063/1.102817, ISSN：0003-6951, CiNii Articles ID：120001370925, SCOPUS ID：0000367334

APPLICATION OF VANDERWAALS EPITAXY TO HIGHLY HETEROGENEOUS SYSTEMS　　　　　　　　　　　　　　　
K SAIKI; K UENO; T SHIMADA; A KOMA
JOURNAL OF CRYSTAL GROWTH, Volume：95, Number：1-4, First page：603, Last page：606, Feb. 1989
English, Scientific journal
DOI：https://doi.org/10.1016/0022-0248(89)90475-2
DOI ID：10.1016/0022-0248(89)90475-2, ISSN：0022-0248, SCOPUS ID：0024605783, Web of Science ID：WOS:A1989T639300138

Characteristic secondary electron emission from graphite and glassy carbon surfaces
Keiji Ueno; Takao Kumihashi; Atsushi Saiki; Atsushi Koma
Japanese Journal of Applied Physics, Volume：27, Number：5A, First page：L759, Last page：L761, 1988
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.27.L759
DOI ID：10.1143/JJAP.27.L759, ISSN：1347-4065, SCOPUS ID：0024011602

Low-energy electron energy loss spectroscopy on YBa2Cu3O7-y
Atsushi Ando; Koichiro Saiki; Keiji Ueno; Atsushi Koma
Japanese Journal of Applied Physics, Volume：27, Number：3A, First page：L304, Last page：L307, 1988
English, Scientific journal
DOI：https://doi.org/10.1143/JJAP.27.L304
DOI ID：10.1143/JJAP.27.L304, ISSN：1347-4065, SCOPUS ID：0023983227

■ MISC

Transport properties of ferromagnetic layered chalcogenide Cr_1/3TaS₂　　　　　　　　　　　　　　　
Yamasaki Y.; Arai M.; Moriya R.; Masubuchi S.; Pyon S.; Tamegai T.; Ueno K.; Machida T.
Meeting Abstracts of the Physical Society of Japan, Volume：72.1, First page：1803, Last page：1803, 2017
遷移金属ダイカルコゲナイドは、層間に異なる元素をインターカレートすることにより強磁性や超伝導などの様々な物性を発現する。我々は劈開可能な層状物質強磁性体の候補として、2H-TaS_2_にCrをインターカレートしたCr_1/3_TaS_2_に着目し、その電気伝導及び磁化特性を調べた。さらにこの物質を劈開した試料における伝導特性についても報告する。
The Physical Society of Japan, Japanese
DOI：https://doi.org/10.11316/jpsgaiyo.72.1.0_1803
DOI ID：10.11316/jpsgaiyo.72.1.0_1803, eISSN：2189-0803, CiNii Articles ID：130006709619

Depth Profile Characterization of Spin-Coated Poly(3,4-ethylenedioxythiophene): Poly(styrene sulfonic acid) Films for Thin-Film Solar Cells during Argon Plasma Etching by Spectroscopic Ellipsometry (Retraction of Vol 50, art no 08JG02, 2011)　　　　　　　　　　　　　　　
Tomohisa Ino; Tatsuya Hayashi; Keiji Ueno; Hajime Shirai
JAPANESE JOURNAL OF APPLIED PHYSICS, Volume：55, Number：8, Aug. 2016
English, Others
DOI：https://doi.org/10.7567/JJAP.55.089201
DOI ID：10.7567/JJAP.55.089201, ISSN：0021-4922, eISSN：1347-4065, Web of Science ID：WOS:000403923600001

Graphene oxide/Crystalline Si solar cells　　　　　　　　　　　　　　　
ONO Masahiro; INO Tomohisa; ISHIKAWA Ryo; GOTOU Takuya; UENO Keiji; SHIRAI Hajime
Technical report of IEICE. OME, Volume：111, Number：369, First page：29, Last page：33, 21 Dec. 2011
Efficient crystalline Si heterojunction solar cells with poly(ethylenehiophene)(PEDOT)-polystyrene sulfonate (PSS) and graphene oxide (GO) composite are demonstrated using a structure of Ag/(PEDOT:PSS:GO)/c-Si (100)(ρ: 3-5 Ω・cm)/Al. The power conversion efficiency enhanced up to 6.5% under illumination of AM1.5 100 mW/cm^2 light. Because of ease of preparation, soluble PEDOT:PSS:GO composite will be promising for hole-transporting layer and transparent conducting layer for crystalline Si photovoltaic applications.
The Institute of Electronics, Information and Communication Engineers, English
ISSN：0913-5685, CiNii Articles ID：110009466889, CiNii Books ID：AN10013334

Organic field-effect transistors with solution-processed graphene electrodes　　　　　　　　　　　　　　　
SUGANUMA Koichi; SAIKI Koichiro; GOTOU Takuya; UENO Keiji
Technical report of IEICE. OME, Volume：111, Number：369, First page：35, Last page：39, 21 Dec. 2011
Solution-processed electrodes for organic field effect transistor (OFET) were fabricated using a graphene oxide (GO) solution. The GO solution was synthesized by oxidation and exfoliation of natural graphite powder. Fabricated graphene electrodes for OFET were available as either bottom- or top-contacted ones. Graphene electrode OFETs showed better OFET performance and higher mobility than those of thermally deposited Au electrode OFETs.
The Institute of Electronics, Information and Communication Engineers, Japanese
ISSN：0913-5685, CiNii Articles ID：110009466890, CiNii Books ID：AN10013334

21aTA-6 Comparison of different methods for fabricating graphene thin films using the chemical exfoliation　　　　　　　　　　　　　　　
Yoshida M.; Saiki K.; Ueno K.
Meeting abstracts of the Physical Society of Japan, Volume：63, Number：2, First page：807, Last page：807, 25 Aug. 2008
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110006985487, CiNii Books ID：AA11439205

低次元構造半導体を用いた新奇薄膜電界効果トランジスタ形成に関する研究　　　　　　　　　　　　　　　
上野啓司; 小野木亮; 阿部重臣; 松本晃; 川端ちひろ; 平岡和; 保戸塚梢; 白石淳子; 高橋新; 武林聡子; 坪倉陽
Volume：平成17-18年度, First page：1, Last page：45, 2007

直鎖π共役電子系の電気伝導度測定に関する研究　　　　　　　　　　　　　　　
上野啓司
Volume：第5号(18年度), First page：553, Last page：554, 2007

低次元構造半導体を用いた新奇薄膜電界効果トランジスタ形成に関する研究　　　　　　　　　　　　　　　
上野啓司; 小野木亮; 阿部重臣; 松本晃; 川端ちひろ; 平岡和; 保戸塚梢; 白石淳子; 高橋新; 武林聡子; 坪倉陽
科学研究費補助金(基盤研究(C)) 研究成果報告書, Volume：平成17-18年度, First page：1, Last page：45, 2007

直鎖π共役電子系の電気伝導度測定に関する研究　　　　　　　　　　　　　　　
上野啓司
総合研究機構研究プロジェクト研究成果報告書, Volume：第5号(18年度), First page：553, Last page：554, 2007

層状化合物を用いた高移動度フレキシブル電界効果トランジスタの開発に関する研究　　　　　　　　　　　　　　　
上野啓司
Volume：第4号(17年度), 2006

Preparation of organic devices by the solution process　　　　　　　　　　　　　　　
上野啓司; 小野木亮; 高橋新; 森朋彦
Volume：7, Number：7, First page：49, Last page：52, 2006
A thin film of 2, 5, 11, 14-tetradodecylhexabenzocoronene (HBC4D) was fabricated by the horizontal lifting transfer of its Langmuir film onto a hydrophobic substrate surface, and characterized by UV-vis optical absorption spectroscopy, X-ray diffraction and atomic force microscopy. A field effect transistor (FET) of HBC4D was also fabricated by the wet process, and its performances were compared with HBC4D-FET fabricated by the vacuum deposition. Highly-ordered growth of the HBC4D thin film was achieved by the wet process, but its FET performances were worse than those of the vacuum-deposited FET.
Japanese
ISSN：1347-4758, CiNii Articles ID：120001371309, CiNii Books ID：AA11808968

層状化合物を用いた高移動度フレキシブル電界効果トランジスタの開発に関する研究　　　　　　　　　　　　　　　
上野啓司
総合研究機構研究プロジェクト研究成果報告書, Volume：第4号(17年度), 2006

溶液系の有機デバイス作製技術検討　　　　　　　　　　　　　　　
上野啓司; 小野木亮; 高橋新; 森朋彦
埼玉大学地域共同研究センター紀要, Volume：7, Number：7, First page：49, Last page：52, 2006
A thin film of 2, 5, 11, 14-tetradodecylhexabenzocoronene (HBC4D) was fabricated by the horizontal lifting transfer of its Langmuir film onto a hydrophobic substrate surface, and characterized by UV-vis optical absorption spectroscopy, X-ray diffraction and atomic force microscopy. A field effect transistor (FET) of HBC4D was also fabricated by the wet process, and its performances were compared with HBC4D-FET fabricated by the vacuum deposition. Highly-ordered growth of the HBC4D thin film was achieved by the wet process, but its FET performances were worse than those of the vacuum-deposited FET.
Japanese
ISSN：1347-4758, CiNii Articles ID：120001371309, CiNii Books ID：AA11808968

27aWB-5 Molecular orientation in pentacene ultra thin films grown on SiO_2 substrates　　　　　　　　　　　　　　　
Yoshikawa G.; Miyadera T.; Ueno K.; Onoki R.; Nakai I.; Entani S.; Ikeda S.; Kiguchi M.; Kondoh H.; Ohta T.; Saiki K.
Meeting abstracts of the Physical Society of Japan, Volume：60, Number：1, First page：875, Last page：875, 04 Mar. 2005
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110004537400, CiNii Books ID：AA11439205

26pYK-6 Time of Flight Measurement of Organic Thin Film FETs　　　　　　　　　　　　　　　
Yamamoto Y.; Shimada T.; Ueno K.; Saiki K.
Meeting abstracts of the Physical Society of Japan, Volume：60, Number：1, First page：803, Last page：803, 04 Mar. 2005
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110004537122, CiNii Books ID：AA11439205

高誘電率ゲート酸化膜を用いた電界効果トランジスタによる有機薄膜の物性変調　　　　　　　　　　　　　　　
上野啓司
Volume：16年度, 2005

高誘電率ゲート酸化膜を用いた電界効果トランジスタによる有機薄膜の物性変調　　　　　　　　　　　　　　　
上野啓司
総合研究機構研究プロジェクト研究成果報告書, Volume：16年度, 2005

Morphological change of C-60 monolayer epitaxial films under photoexcitation　　　　　　　　　　　　　　　
Y Yamamoto; H Ichikawa; K Ueno; A Koma; K Saiki; T Shimada
PHYSICAL REVIEW B, Volume：70, Number：15, First page：155415-1-155415-6, Oct. 2004
English
DOI：https://doi.org/10.1103/PhysRevB.70.155415
DOI ID：10.1103/PhysRevB.70.155415, ISSN：2469-9950, eISSN：2469-9969, Web of Science ID：WOS:000224855900091

13pWH-8 Operating characteristics of an organic FET having a high-k gate oxide layer(FET)　　　　　　　　　　　　　　　
Ueno K.; Onoki R.; Abe S.; Saiki K.
Meeting abstracts of the Physical Society of Japan, Volume：59, Number：2, First page：761, Last page：761, 25 Aug. 2004
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002049847, CiNii Books ID：AA11439205

13pWH-8 Operating characteristics of an organic FET having a high-k gate oxide layer(FET)　　　　　　　　　　　　　　　
Ueno K; Onoki R; Abe S; Saiki K
Meeting abstracts of the Physical Society of Japan, Volume：59, Number：2, First page：506, Last page：506, 25 Aug. 2004
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002054167, CiNii Books ID：AA11439205

STM observation of alkall hallde/metal heterostructures　　　　　　　　　　　　　　　
Katayama M.; Inoue H.; Kiguchi M.; Ueno K.; Saiki K.
Meeting abstracts of the Physical Society of Japan, Volume：58, Number：2, First page：789, Last page：789, 15 Aug. 2003
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002064118, CiNii Books ID：AA11439205

Organic FET using pentaccne thin films grown under anisotropic condition　　　　　　　　　　　　　　　
Ueno K.; Saiki K.
Meeting abstracts of the Physical Society of Japan, Volume：58, Number：2, First page：752, Last page：752, 15 Aug. 2003
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002063824, CiNii Books ID：AA11439205

Film Thickness Dependence of Field Effect Mobility in Pentacene Thin Film　　　　　　　　　　　　　　　
Kiguchi M.; Nakayama M.; Fujiwara S.; Ueno K.; Shimada T.; Saiki K.
Meeting abstracts of the Physical Society of Japan, Volume：58, Number：2, First page：752, Last page：752, 15 Aug. 2003
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002063826, CiNii Books ID：AA11439205

STM observation of LiBr thin films　　　　　　　　　　　　　　　
Katayama M.; Ueno K.; Kiguchi M.; Saiki K.; Koma A.
Meeting abstracts of the Physical Society of Japan, Volume：58, Number：1, First page：880, Last page：880, 06 Mar. 2003
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002223859, CiNii Books ID：AA11439205

表面不活性化シリコン基板上における異方的有機薄膜成長　　　　　　　　　　　　　　　
上野啓司; 斉木幸一朗小間篤
Volume：72, Number：3, First page：322, Last page：326, 2003

表面不活性化シリコン基板上における異方的有機薄膜成長　　　　　　　　　　　　　　　
Volume：28, Number：3, First page：46, Last page：55, 2003

表面不活性化シリコン基板上における異方的有機薄膜成長　　　　　　　　　　　　　　　
上野啓司; 斉木幸一朗小間篤
応用物理, Volume：72, Number：3, First page：322, Last page：326, 2003

表面不活性化シリコン基板上における異方的有機薄膜成長　　　　　　　　　　　　　　　
応用物理, Volume：28, Number：3, First page：46, Last page：55, 2003

STM observation of LiBr/Si(001) heterostructure　　　　　　　　　　　　　　　
Katayama M.; Ueno K.; Kiguchi M.; Saiki K.; Koma A.
Meeting abstracts of the Physical Society of Japan, Volume：57, Number：2, First page：779, Last page：779, 13 Aug. 2002
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110009719873, CiNii Books ID：AA11439205

Mechanism of the visible light photoemission from alkali halide thin films induced by UV irradiation　　　　　　　　　　　　　　　
Yoshikawa G.; Kiguchi M.; Ueno K.; Saiki K.; Koma A.
Meeting abstracts of the Physical Society of Japan, Volume：57, Number：2, First page：779, Last page：779, 13 Aug. 2002
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110009719872, CiNii Books ID：AA11439205

Highly stable passivation of a Si(111) surface using bilayer-GaSe　　　　　　　　　　　　　　　
K Ueno; H Shirota; T Kawamura; T Shimada; K Saiki; A Koma
APPLIED SURFACE SCIENCE, Volume：190, Number：1-4, First page：485, Last page：490, May 2002
English
DOI：https://doi.org/10.1016/S0169-4332(01)00923-0
DOI ID：10.1016/S0169-4332(01)00923-0, ISSN：0169-4332, CiNii Articles ID：120001370987, Web of Science ID：WOS:000176520700090

Epitaxial growth of a vacancy-ordered Ga2Se3 thin film on a vicinal Si(001) substrate　　　　　　　　　　　　　　　
K Ueno; S Tokuchi; K Saiki; A Koma
JOURNAL OF CRYSTAL GROWTH, Volume：237, Number：2, First page：1610, Last page：1614, Apr. 2002
English
DOI：https://doi.org/10.1016/S0022-0248(01)02353-3
DOI ID：10.1016/S0022-0248(01)02353-3, ISSN：0022-0248, Web of Science ID：WOS:000176512900139

Epitaxial growth and electronic structure of a C-60 derivative prepared by using a solution spray technique　　　　　　　　　　　　　　　
T Shimada; H Nakatani; K Ueno; A Koma; Y Kuninobu; M Sawamura; E Nakamura
JOURNAL OF APPLIED PHYSICS, Volume：90, Number：1, First page：209, Last page：212, Jul. 2001
English
DOI：https://doi.org/10.1063/1.1379052
DOI ID：10.1063/1.1379052, ISSN：0021-8979, CiNii Articles ID：120001370931, Web of Science ID：WOS:000169361100030

STM observation of a bilayer-GaSe terminated Si(111) surface.　　　　　　　　　　　　　　　
Shirota H.; Ueno K.; Saiki K.; Koma A.
Meeting abstracts of the Physical Society of Japan, Volume：56, Number：1, First page：820, Last page：820, 09 Mar. 2001
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002164817, CiNii Books ID：AA11439205

表面不活性基板を利用した有機・無機ナノ構造の形成(<小特集>ナノ結晶)　　　　　　　　　　　　　　　
上野啓司; 小間篤
Volume：28, Number：3, First page：164, Last page：173, 2001
DOI：https://doi.org/10.19009/jjacg.28.3_164
DOI ID：10.19009/jjacg.28.3_164

表面不活性基板を利用した有機・無機ナノ構造の形成(<小特集>ナノ結晶)　　　　　　　　　　　　　　　
上野啓司; 小間篤
日本結晶成長学会誌, Volume：28, Number：3, First page：164, Last page：173, 2001
New-type nanostructures of organic molecules and inorganic semiconductors have been successfully fabricated on 'inactive' substrate surfaces such as layered material surfaces and dangling-bond terminated semiconductor surfaces. In this article we introduce two examples of our methods. One is the fabrication of C_<60> molecular nanostructures on a GaSe/MoS2 heterostructure substrate by the selective growth method. The other is the fabrication of self-organized compound semiconductor quantum dots on a bilayer-GaSe terminated Si(111) substrate. The use of the inactive substrate surfaces opens a new way to fabricate position-controlled nanostructures, which have been difficult to form by conventional self-organization methods.
The Japanese Association for Crystal Growth (JACG), Japanese
DOI ID：10.19009/jjacg.28.3_164, ISSN：0385-6275, CiNii Articles ID：110002715468, CiNii Books ID：AN00188386

Layered Material Substrates　　　　　　　　　　　　　　　
UENO Keiji; KOMA Atsushi
Journal of the Surface Science Society of Japan, Volume：21, Number：11, First page：716, Last page：723, 10 Nov. 2000
Japanese
ISSN：0388-5321, CiNii Articles ID：10005348918, CiNii Books ID：AN00334149

Investigation of the growth mechanism of an InSe epitaxial layer on a MoS2 substrate　　　　　　　　　　　　　　　
T Hayashi; K Ueno; K Saiki; A Koma
JOURNAL OF CRYSTAL GROWTH, Volume：219, Number：1-2, First page：115, Last page：122, Oct. 2000
English
DOI：https://doi.org/10.1016/S0022-0248(00)00627-8
DOI ID：10.1016/S0022-0248(00)00627-8, ISSN：0022-0248, CiNii Articles ID：120001370934, Web of Science ID：WOS:000089675700015

C(1s) core-electron excitation of C_<60>/Si(111) systems.　　　　　　　　　　　　　　　
Iizumi K.; Ueno K.; Saiki K.; Koma A.
Meeting abstracts of the Physical Society of Japan, Volume：55, Number：2, First page：749, Last page：749, 10 Sep. 2000
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002150110, CiNii Books ID：AA11439205

Surface structure of a bilayer-GaSe teminated Si(111) substrate and its application to thin film growth.　　　　　　　　　　　　　　　
Shirota H.; Iizumi K.; Ueno K.; Saiki K.; Koma A.
Meeting abstracts of the Physical Society of Japan, Volume：55, Number：2, First page：777, Last page：777, 10 Sep. 2000
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002150687, CiNii Books ID：AA11439205

Investigation of epitaxial arrangement and electronic structure of a La@ C-82 film grown on an MoS2 surface　　　　　　　　　　　　　　　
K Iizumi; Y Uchino; K Ueno; A Koma; K Saiki; Y Inada; K Nagai; Y Iwasa; T Mitani
PHYSICAL REVIEW B, Volume：62, Number：12, First page：8281, Last page：8285, Sep. 2000
English
DOI：https://doi.org/10.1103/PhysRevB.62.8281
DOI ID：10.1103/PhysRevB.62.8281, ISSN：1098-0121, eISSN：1550-235X, Web of Science ID：WOS:000089593400085

Investigation of epitaxial arrangement and electronic structure of a La@ C-82 film grown on an MoS2 surface
上野啓司; 小間篤
PHYSICAL REVIEW B, Volume：62, Number：12, First page：8281, Last page：8285, Sep. 2000
Copyright notice(c)2000 American Physical Society. All rights reserved. Publisher's version: http://link.aps.org/abstract/PRB/v62/p8281Molecular arrangement and electronic structure of a La@C-82 film epitaxially grown on an MoS2 surface have been studied using reflection high-energy electron diffraction and electron energy-loss spectroscopy (EELS). It was revealed that La@C-82 molecules form a close-packed hexagonal lattice on a cleaved face of MoS2 with the intermolecular distance of 1.13+/-0.03 nm. EELS of the La@C-82 film in the valence excitation region indicated seven peaks coming from pi-->pi* transitions together with the pi-plasmon excitation. The absence of a distinct band gap means that the La@C-82 epitaxial him is not semiconducting, but metallic or semimetallic. From the EELS result, we propose an electronic structure diagram of the La@C-82 epitaxial film.
American Physical Society, English
ISSN：0163-1829, CiNii Articles ID：120001370971

Epitaxy of fullerene molecules on Si substrates terminetaed by foreign atoms　　　　　　　　　　　　　　　
UENO Keiji
Technical report of IEICE. OME, Volume：100, Number：245, First page：51, Last page：56, 21 Jul. 2000
There are active dangling bonds on a clean surface of Si(111), but the surface can be passivated by termintating those bonds using appropriate atoms. The surface regularly terminated by foreign atoms is as inactive as the cleaved surface of a layered material such as MoS_2 or GaSe, and the surface energy is quite low. Then it is possible to utilize this surface as the substrate to grow an epitaxial thin film of such organic molecular crystals as fullerene and metal-phthalocyanine via the van der Waals interaction. In this paper I will explain the method for terminating a Si(111) surface by hydrogen, arsenic or bilayer-GaSe, and report on the growth of C_<60> thin films on these dangling bond terminated Si(111) surfaces. In addition, I will report about the measurement of the electronic structure of grown C_<60> films.
The Institute of Electronics, Information and Communication Engineers, Japanese
ISSN：0913-5685, CiNii Articles ID：110003301168, CiNii Books ID：AN10013334

Electronic structure of C_<60> molecules adsorbed on Si(111) surfaces terminated by foreign atoms　　　　　　　　　　　　　　　
Ueno K.; Shirota H.; Iizumi K.; Saiki K.; Koma A.
Meeting abstracts of the Physical Society of Japan, Volume：55, Number：1, First page：782, Last page：782, 10 Mar. 2000
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110001916742, CiNii Books ID：AA11439205

Electron Energy Loss Spectroscopy of (C_<60>,K)/Si(111) systems.　　　　　　　　　　　　　　　
Iizumi K.; Ueno K.; Saiki K.; Koma A.
Meeting abstracts of the Physical Society of Japan, Volume：55, Number：1, First page：749, Last page：749, 10 Mar. 2000
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110001916354, CiNii Books ID：AA11439205

Growth mechanism of a III-VI layered compound semiconductor thin film grown on a MoS_2 substrate　　　　　　　　　　　　　　　
Hayashi T.; Ueno K.; Saiki K.; Koma A.
Meeting abstracts of the Physical Society of Japan, Volume：55, Number：1, First page：759, Last page：759, 10 Mar. 2000
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110001916471, CiNii Books ID：AA11439205

24aZ-6 Electron Energy Loss Spectroscopy of C_<60> monolayer films grown on Si(111)-7×7 and Si(100)-2×1 surfaces　　　　　　　　　　　　　　　
Iizumi K.; Ueno K.; Saiki K.; Koma A.
Meeting abstracts of the Physical Society of Japan, Volume：54, Number：2, First page：785, Last page：785, 03 Sep. 1999
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110001994330, CiNii Books ID：AA11439205

24aZ-1 Photoyield measurement on alkali halide / semiconductor heterostructures (II)　　　　　　　　　　　　　　　
Kono T.; Saiki K.; Ueno K.; Koma A.
Meeting abstracts of the Physical Society of Japan, Volume：54, Number：2, First page：783, Last page：783, 03 Sep. 1999
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110001994325, CiNii Books ID：AA11439205

26aPS-34 Epitaxial growth and electron spectroscopy measurement of Ga_2Se_3 thin films on Si substrates　　　　　　　　　　　　　　　
Ueno K; Nakahara T; Iizumi K; Saiki K; Koma A; Dai Z.R.; Ohuchi F
Meeting abstracts of the Physical Society of Japan, Volume：54, Number：2, First page：820, Last page：820, 03 Sep. 1999
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110001994464, CiNii Books ID：AA11439205

26aPS-13 High Resolution Electron Energy Loss Spectroscopy of C_<60> monolayer films grown on a Si(111)-√<3>x√<3>Ag surface　　　　　　　　　　　　　　　
Iizumi K; Ueno K; Saiki K; Koma A
Meeting abstracts of the Physical Society of Japan, Volume：54, Number：2, First page：815, Last page：815, 03 Sep. 1999
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110001994444, CiNii Books ID：AA11439205

31a-S-12 Electron Energy Loss Spectroscopy of C-<60> monolayer films grown on inactive surfaces　　　　　　　　　　　　　　　
Iizumi K.; Ueno K.; Saiki K.; Koma A.
Meeting abstracts of the Physical Society of Japan, Volume：54, Number：1, First page：338, Last page：338, 15 Mar. 1999
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002220666, CiNii Books ID：AA11439205

28p-S-9 Photoyield measurement on alkali halide / semiconductor heterostructures　　　　　　　　　　　　　　　
Kono T.; Saiki K.; Ueno K.; Koma A.
Meeting abstracts of the Physical Society of Japan, Volume：54, Number：1, First page：306, Last page：306, 15 Mar. 1999
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002220202, CiNii Books ID：AA11439205

Structure of C_<60> thin films epitaxially grown on various layered material substrates.　　　　　　　　　　　　　　　
UENO K.; IIZUMI K.; SAIKI K.; KOMA A.
Meeting abstracts of the Physical Society of Japan, Volume：53, Number：2, First page：396, Last page：396, 05 Sep. 1998
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002056924, CiNii Books ID：AA11439205

Growth mechanism of InSe thin films grown on MoS_2 substrates.　　　　　　　　　　　　　　　
HAYASHI T.; UENO K.; SAIKI K.; KOMA A.
Meeting abstracts of the Physical Society of Japan, Volume：53, Number：2, First page：378, Last page：378, 05 Sep. 1998
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002056781, CiNii Books ID：AA11439205

Fabrication of Molecular Crystal Nanostructures by a Selective Growth Method　　　　　　　　　　　　　　　
UENO Keiji; SHIMADA Toshihiro; KOMA Atsushi
Journal of the Surface Science Society of Japan, Volume：19, Number：1, First page：14, Last page：20, 10 Jan. 1998
Japanese
ISSN：0388-5321, CiNii Articles ID：10009861740, CiNii Books ID：AN00334149

表面を選ぶサッカーボール　　　　　　　　　　　　　　　
上野啓司
Volume：13, Number：11, First page：47, Last page：50, 1998

表面を選ぶサッカーボール　　　　　　　　　　　　　　　
上野啓司
物理科学雑誌パリティ, Volume：13, Number：11, First page：47, Last page：50, 1998
Japanese
ISSN：0911-4815, CiNii Articles ID：120001370937, CiNii Books ID：AN10017131

7a-PS-58 Selective Growth of Organic Mlecular Crystals on Layered Material Substrates　　　　　　　　　　　　　　　
Ueno K.; Sasaki K.; Koma A.
Meeting abstracts of the Physical Society of Japan, Volume：52, Number：2, First page：369, Last page：369, 16 Sep. 1997
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002061306, CiNii Books ID：AA11439205

31a-T-12 2D layered material buffer layers in large lattice mismatch heterostructures:The system CdS/InSe/Si　　　　　　　　　　　　　　　
Loher T; Ueno K; Koma A
Meeting abstracts of the Physical Society of Japan, Volume：52, Number：1, First page：364, Last page：364, 17 Mar. 1997
The Physical Society of Japan (JPS), English
ISSN：1342-8349, CiNii Articles ID：110002237728, CiNii Books ID：AA11439205

29a-PS-31 SPM observation of heteroepitaxially grown III-VI layered semiconductor thin film surface.　　　　　　　　　　　　　　　
Ueno K; Sasaki K; Koma A
Meeting abstracts of the Physical Society of Japan, Volume：52, Number：1, First page：338, Last page：338, 17 Mar. 1997
The Physical Society of Japan (JPS), Japanese
ISSN：1342-8349, CiNii Articles ID：110002237630, CiNii Books ID：AA11439205

Initial growth mechanism of C_<60> epitaxial thin films　　　　　　　　　　　　　　　
Sugai M.; Saiki K.; Koma A.
Abstracts of the meeting of the Physical Society of Japan. Sectional meeting, Volume：1996, Number：2, First page：572, Last page：572, 13 Sep. 1996
The Physical Society of Japan (JPS), Japanese
CiNii Articles ID：110001985810, CiNii Books ID：AN10453836

27p-PSA-7 Characterization of heteroepitaxially grown layerd materials by HREELS.　　　　　　　　　　　　　　　
Ueno K; Fujikawa Y; Wei Gao; Saiki K; Koma A
Volume：1992, Number：2, First page：491, Last page：491, 14 Sep. 1992
The Physical Society of Japan (JPS), Japanese
CiNii Articles ID：110001999247, CiNii Books ID：AA11823236

29p-PS-18 Van der waals Epitaxy on Hydrogen-terminated Si Substrate.　　　　　　　　　　　　　　　
Liu K; Ueno K; Saiki K; Koma A
Volume：47, Number：2, First page：467, Last page：467, 12 Mar. 1992
The Physical Society of Japan (JPS), Japanese
CiNii Articles ID：110002173617, CiNii Books ID：AN10453938

30p-BPS-2 STM Observation of Heteroepitaxially Grown Layered Materials　　　　　　　　　　　　　　　
Ueno K.; Yamamoto H.; Mori T.; Yoshii K.; Saiki K.; Koma A.
Volume：46, Number：2, First page：462, Last page：462, 12 Sep. 1991
The Physical Society of Japan (JPS), Japanese
CiNii Articles ID：110002154207, CiNii Books ID：AN10453938

27p-R-6 Growth and Characterization of (GaSe/MoSe_2)_n Superlattice on GaAs　　　　　　　　　　　　　　　
Ueno K.; Abe H.; Saiki K.; Koma A.
Volume：1991, Number：2, First page：514, Last page：514, 11 Mar. 1991
The Physical Society of Japan (JPS), Japanese
CiNii Articles ID：110001905439, CiNii Books ID：AA11403638

PERIODIC LATTICE-DISTORTIONS AS A RESULT OF LATTICE MISMATCH IN EPITAXIAL-FILMS OF 2-DIMENSIONAL MATERIALS　　　　　　　　　　　　　　　
BA PARKINSON; FS OHUCHI; K UENO; A KOMA
APPLIED PHYSICS LETTERS, Volume：58, Number：5, First page：472, Last page：474, Feb. 1991
English
DOI：https://doi.org/10.1063/1.104611
DOI ID：10.1063/1.104611, ISSN：0003-6951, CiNii Articles ID：120001370928, Web of Science ID：WOS:A1991EW47700014

2a-E-12 STM observation of the heterostructure grown by Van der Waals epitaxy method.　　　　　　　　　　　　　　　
Ueno K.; Saiki K.; Koma A.; Parkinson B.A.; Ohuchi F.
Volume：1990, Number：2, First page：418, Last page：418, 12 Sep. 1990
The Physical Society of Japan (JPS), Japanese
CiNii Articles ID：110002023554, CiNii Books ID：AA11823236

VANDERWAALS EPITAXIAL-GROWTH AND CHARACTERIZATION OF MOSE2 THIN-FILMS ON SNS2　　　　　　　　　　　　　　　
FS OHUCHI; BA PARKINSON; K UENO; A KOMA
JOURNAL OF APPLIED PHYSICS, Volume：68, Number：5, First page：2168, Last page：2175, Sep. 1990
English
DOI：https://doi.org/10.1063/1.346574
DOI ID：10.1063/1.346574, ISSN：0021-8979, CiNii Articles ID：120001370927, Web of Science ID：WOS:A1990DW26700034

■ Thesis Guidance

2024

2024

■ Affiliated academic society

Present

Present

Present

Present

■ Research projects

Integration of 2 dimensional tunnel FET for ultra-low power consumption system　　　　　　　　　　　　　　　
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (S), 27 Apr. 2022 - 31 Mar. 2027
The University of Tokyo
Grant amount(Total)：200070000, Direct funding：153900000, Indirect funding：46170000
Grant number：22H04957

Synthesis of Ultrathin Functional Oxides Using Atomically Thin Transition Metal Dichalcogenides as Oxidation Precursors　　　　　　　　　　　　　　　
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), 01 Apr. 2022 - 31 Mar. 2026
Kansai University
Grant amount(Total)：17290000, Direct funding：13300000, Indirect funding：3990000
Grant number：23K23182

Synthesis of Ultrathin Functional Oxides Using Atomically Thin Transition Metal Dichalcogenides as Oxidation Precursors　　　　　　　　　　　　　　　
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), 01 Apr. 2022 - 31 Mar. 2026
Kansai University
Grant amount(Total)：17290000, Direct funding：13300000, Indirect funding：3990000
Grant number：22H01914

触媒効果による層状化合物原子膜の低温単結晶成長実現　　　　　　　　　　　　　　　
01 Apr. 2021 - 31 Mar. 2024
Grant amount(Total)：4160000, Direct funding：3200000, Indirect funding：960000
Grant number：21K04826

Low-temperature van der Waals epitaxy using high vapor pressure sources　　　　　　　　　　　　　　　
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), 01 Apr. 2018 - 31 Mar. 2021
Ueno Keiji, Saitama University
Grant amount(Total)：16510000, Direct funding：12700000, Indirect funding：3810000
In order to epitaxially grow single-crystalline ultra-thin films of layered transition metal dichalcogenides at low substrate temperatures, we have set up a molecular beam epitaxy system using highly reactive high-vapor pressure precursor compounds as source materials and proceeded with deposition experiments. As a result, tungsten disulfide, niobium disulfide, and niobium diselenide thin films were successfully epitaxially grown on synthetic mica and other substrates.
In deposition experiments using an atomic layer deposition system, it was found that crystalline tungsten disulfide thin films can be grown not only on the metal film but also on the external substrate surface at lower temperatures than those without the metal film, by depositing a small metal film on a thermally oxidized silicon substrate in advance.
Grant number：18H01822

International supports of atomic layered materials and promoting the collaborated research　　　　　　　　　　　　　　　
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area), 06 Nov. 2015 - 31 Mar. 2019
Saito Riichiro; NISHINA yuta; YANAGI kazuhiro; KAWANO yukio, Tohoku University
Grant amount(Total)：45890000, Direct funding：35300000, Indirect funding：10590000
Atomic layered materials, which are the thinnest material in the nature, have shown unique and significant properties and thus the research of the atomic layered materials are very active in the world for recent decades. In particular, hexagonal boron nitride (h-BN) is an important atomically-flat materials which can produce only in Japan. In this project, we support the supply of hBN samples internationally to enhance the international collaboration, which is very efficient for promoting the activity not only domestic but also international research. Further, sending or inviting many young researchers for the international collaborating research on atomic layer materials by this project, we encourage young scientists to establish a new network of the research. This is an important results of the project for our continuing the research for the next generation.
Grant number：15K21722

Understanding and device application of the hetero-atomic layers　　　　　　　　　　　　　　　
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area), 28 Jun. 2013 - 31 Mar. 2018
NAGASHIO Kosuke; WATANABE Kenji; YAMADA Takatoshi, The University of Tokyo
Grant amount(Total)：204230000, Direct funding：157100000, Indirect funding：47130000
In the research of atomic layers for Scientific Research on Innovative Areas, (1) the transport properties of 2 dimensional layered semiconductors, (2) fabrication technique for the layered heterostructure, and its transport properties and (3) application to the OLED were studied. Compared with the conventional heteroepitaxy, layered heterostructure can be fabricated without considering the lattice mismatch. The layered heterointerface is proved to be electrically inert. Further development can be expected.
Grant number：25107004

Promotion of Science Atomic layers　　　　　　　　　　　　　　　
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area), 28 Jun. 2013 - 31 Mar. 2018
Saito Riichiro, Tohoku University
Grant amount(Total)：181740000, Direct funding：139800000, Indirect funding：41940000
In this project, we have synthesized the thinnest material in the history of human, that is, atomic layered materials. Using the synthesized, atomic layered materials, we have developed electronic or optical devices that require minimum consumption of the power, which enable us the possible applications for the commercial market. Further, stacking these atomic layered materials one by one, we make a completely new materials which enables a new properties such as two-dimensional superconductivity or quantum devices. This research activity is enhanced by the international collaboration of the researches.
Grant number：25107001

Development of high performance organic thin film devices by utilizing the junction between graphene and organic semiconductor　　　　　　　　　　　　　　　
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), 2010 - 2012
UENO Keiji, Saitama University
Grant amount(Total)：4290000, Direct funding：3300000, Indirect funding：990000
In the present research, it has been tried to improve the performance of solar cells and field-effect transistors by using chemically exfoliated solubilized graphene as the constituent material of these devices. By adding solubilized graphene, photoconversion efficiency of the solution-processed thin film solar cell was improved to be higher than 12 %. It was also realized to obtain three times higher mobility of an organic thin film field-effect transistor by adding the solubilized graphene, and to fabricate a transparent transistor by using graphene transparent electrodes.
Grant number：22560002

層状物質の薄片剥離およびヘテロ積層による新奇物性発現　　　　　　　　　　　　　　　
2007 - 2008
Grant amount(Total)：3300000, Direct funding：3300000
Grant number：19656011

Fabrication of novel thin film transistors by using low-dimensional structure semiconductors　　　　　　　　　　　　　　　
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), 2005 - 2006
UENO Keiji, Saitama University
Grant amount(Total)：3600000, Direct funding：3600000
In this research, I tried to fabricate a "flexible" and "high-quality" thin film transistor by using such "anisotropic" structure low-dimensional materials as organic macromolecule polymers and inorganic layered structure semiconductors. For two years research, following results have been obtained.
(1)Optimization of the fabrication process of a SiOx gate substrate surface that has an anisotropic template structure.
(2)Establishment of the fabrication process of a highly ordered thin film of a diacetylene derivative compound.
(3)Successful fabrication of highly ordered and defect-free ;t-conjugated systems by the anisotropic polymerization of a highly-ordered diacetylene derivative thin film.
(4)Successful fabrication of an organic field effect transistor on a mica gate dielectric.
(5)Successful transfer of the anisotropic template surface structure by the imprinting method onto an amorphous surface.
(6)Successful fabrication of a. highly ordered thin film of a polythiophene derivative compound onto the template substrate surface by the horizontal lifting method.
(7)Successful position-selective fabrication of C_<60>domains on the SiOx template substrate surface that has the one-dimensional periodic structures.
(8)Improvement in the performances of the organic field effect transistor fabricated on the mica gate dielectric by inserting a PMMA or OTMS shielding layer between the mica surface and the organic film.
(9)Investigation of the exfoliation method of such layered materials as MoS_2, WSe_2, graphite, etc.
Grant number：17550165

高度界面制御有機・無機複合構造による量子物性の発現と応用　　　　　　　　　　　　　　　
2002 - 2006
Grant amount(Total)：526370000, Direct funding：431780000, Indirect funding：94590000
Grant number：14GS0207

有機超伝導薄膜からのコヒーレント光超放射に関する研究　　　　　　　　　　　　　　　
2002 - 2003
Grant amount(Total)：3400000, Direct funding：3400000
Grant number：14750006

Research of "vacancy epitaxy"　　　　　　　　　　　　　　　
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), 2000 - 2001
UENO Keiji, The University of Tokyo
Grant amount(Total)：3600000, Direct funding：3600000
(1) I tried to grow Ga vacancy-ordered Ga_2Se_3 epitaxial films on Si (100) substrates. In order to obtain a single-domain epitaxial film I used a vicinal Si (001) substrare, whose clean surface has the 2×1 single-domain reconstruction. In addition, the lattice constant of the Si is almost same with that of Ga_2Se_3. It has been found that Ga vacancy-ordered single-domain Ga_2Se_3 films can be grown on the vicinal Si (001) substrates with the growth condisions ; substrate temperature = 480℃, VI/III ratio > 100. At the substrate temperature higher than 500℃, no Ga vacancy ordering was observed. At lower substrate temperature than 420 ℃, polycrystalline growth occurred. At the VI/III ratio of 10, no Ga vacancy-ordering was found, too. Photoluminescence spectra taken at 6.5K showed very btoad luminescence peak around 650 〜 1000 nm. No polarized photoluminescence was observed from the Ga vacancy-ordered Ga2Se3 film, which suggests that the grown film on the vicinal Si (001) substrate has the monoclinic crystal structure.
Grant number：12650006

フラーレンおよびその化合物のヘテロ構造化による新物性の探求　　　　　　　　　　　　　　　
1999 - 2000
Grant amount(Total)：3700000, Direct funding：3700000
Grant number：11165212

分子性結晶を用いた室温動作単電子トンネル素子の研究　　　　　　　　　　　　　　　
1998 - 1999
Grant amount(Total)：2100000, Direct funding：2100000
Grant number：10750006

Fabrication of their properties　　　　　　　　　　　　　　　
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (A), 1998 - 1999
KOMA Atsushi; SHIMADA Toshihiro; UENO Keiji; SAIKI Koichiro, The University of Tokyo
Grant amount(Total)：38900000, Direct funding：38900000
This project has aimed at establishing techniques necessary to fabricate highly heterogeneous crystalline structures among various materials from inorganic to inorganic and from insulators to superconductors. Novel physical properties are being found from those exotic structures.
(1) A complex heterostructure to achieve a rocksalt oxide film on GaAs
A single-crystalline MgO film was grown on GaAs (001) by constructing a complex heterostructure with two alkali halide buffer layers. The growth temperature was decreased to 150℃ as compared with direct growth of MgO on GaAs (001). Electron energy loss spectrum of the grown film agreed well with that of bulk MgO, indicating that surface stoichiometry was maintained. The structure was stable up to 600℃ against heating in, UHV condition. The concept of a complex heterostructure will help fabrication of functional oxide layers on GaAs substrates and lead to oxide/semiconductor integrated devices.
(2) Epitaxial growth and phase transition of liquid crystal monolayers
Monolayer films of liquid crystals on single-crystalline inorganic substrates are expected to reveal novel properties involving phase transitions in two dimensions. It was found that liquid crystal 12CB can be grown epitaxially on alkali halide (OO1) surfaces. Temperature dependence of the film structure was investigated by using high-sensitive reflection high energy electron diffraction and atomic force microscopy. The shape of the monolayer boundary drastically changes with the substrate temperature near the transition temperature of 12CB.
(3) Selective growth of molecular materials for quantum structures
Selective growth is the only practical method to fabricate well-defined nanostructures of molecular materials in large scales. Difference in the stabilization energies at film-substrate interfaces is essential to achieve high selectivity. Two guiding principles have been established. One is the use of lattice matching of the grown film and the substrate materials which is found among ionic substrate materials. The other is the use of different van der Waals interaction which is found using layered materials.
(4) Physical properties of ultrathin films and heterostructures
Physical properties of fabricated structures were measured and novel properties are being revealed. For example, MnPc ultrathin film shows magnetic properties different from bulk single crystals due to different molecular arrangement.
Grant number：10305002

Fabrication of novel functional surfaces through ionic crystal / semiconductor heterostructurse and their properties　　　　　　　　　　　　　　　
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (B), 1997 - 1998
SAIKI Koichiro; UENO Keiji, The University of Tokyo
Grant amount(Total)：13900000, Direct funding：13900000
The results of the present research are summarized.
(1) Initial oxidation process of Mg and Ba films studied by electron spectroscopies
MgO and BaO, which are lattice matched to GaAs and Si, could be expected to be key materials to integrate functional perovskite oxides with highly developed semiconductor technologies. In the present work we have revealed the initial oxidation process of Mg and Ba films using Auger electron spectroscopy, electron energy loss spectroscopy and ultraviolet photoelectron spectroscopy. The conditions of oxidation such as critical oxygen exposure, appropriate substrate temperature, etc. have been clarified.
(2) Evaluation of alkali halide hetero-interface by high sensitive RHEED analysis
The interface of alkali halide heterostructures have been analyzed by reflection high energy electron diffraction (RHEED). The disadvantage of this method is that the probing electron causes damage to the growing film. In the present work we have devised high sensitive RHEED apparatus using micro channel plate (MCP), which could reduce the probing current by as much as 1/8000. With this apparatus we could observe the initial growth process of alkali halide films and clarified the mechanism in detail.
(3) A complex heterostructure to achieve a rocksalt oxide film on GaAs
A single-crystalline MgO film was grown on GaAs(001) by constructing a complex heterostructure with two alkali halide buffer layers. The growth temperature was decreased to 150 ﾟC as compared with direct growth of MgO on GaAs(001). Electron energy loss spectrum of the grown film agreed well with that of bulk MgO, indicating that surface stoichiometry was maintained. The structure was stable up to 600ﾟC against heating in UHV condition. The concept of a complex heterostructure will help fabrication of functional oxide layers on GaAs substrates and lead to oxide/semiconductor integrated devices.
(4) Photoyield measurement of alkali halide/semiconductor heterostructure
We have devised a new apparatus to measure a photoyield from the film surface. The photoyield from the NaCl/GaAs heterostructure with various NaCl thickness have been measured up to now. This provides the photo threshold for the electron emission and additive information on the band alignment of the exotic heterostructure such as NaCl/GaAs.
Grant number：09450006

STM/AFMによる層状物質基板上への超微細構造の作製　　　　　　　　　　　　　　　
1996 - 1996
Grant amount(Total)：1000000, Direct funding：1000000
Grant number：08750009

原子モアレ変調構造の走査トンネル分光　　　　　　　　　　　　　　　
1995 - 1995
Grant amount(Total)：2000000, Direct funding：2000000
Grant number：07225204

ファンデアワールス・エピタキシ-法によるフラーレン超薄膜の作製とその物性の解明　　　　　　　　　　　　　　　
1995 - 1995
Grant amount(Total)：2000000, Direct funding：2000000
Grant number：07213207

表面をSTM/AFMで修飾した基板上への結晶成長に関する研究　　　　　　　　　　　　　　　
1994 - 1994
Grant amount(Total)：900000, Direct funding：900000
Grant number：06750004

ファンデアワールス・エピタキシ-法によるフラーレン超薄膜の作製とのその物性の解明　　　　　　　　　　　　　　　
1994 - 1994
Grant amount(Total)：1700000, Direct funding：1700000
Grant number：06224206

原子モアレ変調構造の走査トンネル分光　　　　　　　　　　　　　　　
1994 - 1994
Grant amount(Total)：2300000, Direct funding：2300000
Grant number：06236204

Fabrication and Physical Properties of Organic-Inorganic Superlattice　　　　　　　　　　　　　　　
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for General Scientific Research (B), 1993 - 1994
KOMA Atsushi; SHIMADA Toshihiro; UENO Keiji, The University of Tokyo
Grant amount(Total)：7300000, Direct funding：7300000
This project was aimed at the fabrication and the pursuit of novel physical properties of organic-inorganic epitaxial superlattices. The method of fabrication was van der Waals epitaxy, which utilizes molecular beam epitaxy technique to van der Waals interfaces. The results obtained are as follows : (1) The first example of organic-inorganic EPITAXIAL superlattice has been presented using KBr-VOPc (vanadyl phthalocyanine) system.(2) By using AFM (atomic force microscope), it has been found that the morphology of the grown organic films can be controlled by changing the substrate temperature and molecular beam flux. This result is important to fabricate atomically uniform superlattices.(3) It was demonstrated that the molecular orientation can be controlled by regularly-spaced steps of vicinal substrates. This method is expected to be useful to suppress the formation of multi-domain structure which deteriorates the crystallinity of organic-inorganic superlattices. It will also be useful to fabricate 'quantum wells' , or onedimensionally ordered structure of organic molecules.(4) Capping of organic micro structure by inorganic material for protection is achieved for the first time by using the idea of organic-inorganic superlattice.(5) As new materials combinations for organic-inorganic heteroepitaxy, metal phathalocyanines on Se-terminated GaAs (111) substrates, and squaric acid (C_4H_2O_4) on alkali halides were introduced.
Grant number：05452093

異種構造物質間でのヘテロエピタキシ-に関する研究　　　　　　　　　　　　　　　
1993 - 1993
Grant amount(Total)：900000, Direct funding：900000
Grant number：05750005

ファンデアワールス・エピタキシー法によるフラーレン超薄膜の作製とその物性の解明　　　　　　　　　　　　　　　
1993 - 1993
Grant amount(Total)：3000000, Direct funding：3000000
Grant number：05233208

ファンデアワールス相互作用によるヘテロエピタキシャル成長と界面構造の解明　　　　　　　　　　　　　　　
1993 - 1993
Grant amount(Total)：3100000, Direct funding：3100000
Grant number：05211206

原子モアレ変調構造の走査トンネル分光　　　　　　　　　　　　　　　
1993 - 1993
Grant amount(Total)：3700000, Direct funding：3700000
Grant number：05245203

Exploring Study of Novel Properties in Artificially Stacked Materials Grown by van der Waals Epitaxy　　　　　　　　　　　　　　　
Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Specially Promoted Research, 1990 - 1992
KOMA Atsushi; UENO Keiji; TADA Hirokazu; SAIKI Koichiro; AOKI Hideo, University of Tokyo
Grant amount(Total)：220000000, Direct funding：220000000
This project has been fulfillled to create new artificially stacked materials made of highly heterogeneous layrs and to explore novel properties they show. By extending the idea of van der Waals epitaxy developed by us we have succeeded to grow various kinds of heterostructures. The concept of dangling bond termination has made it possible to grow many layred materials on such ordinary three-dimensional materials as GaAs and Si. Good epitaxial films of fullerene and many organic molecular meterials have also been fabricated successfully. Success in heteroepitaxy between lattice-mismatched alkali halides or polar organic materials on alkali halide by using electrostatic interaction has also increased the possible combination of materials in heteroepitaxy. New properties found and investigated in the present project include moiree-type modulation in STM image, polytype and charge density state formations in ultrathin films, control of optical properties of phthalocyanien films by stacking and anomaly in surface polariton dispersion in ultrathin epitaxial films of alkali halides. Crystal growth, crystal structure, electronic properties, superconductivity dielectric properties in the artificially stacked structures have been investigated theoretically by means of Monte Carlo study, Band, calculation, Quantum Monte Carlo study of analytical method. The occurrence of superconductivity due to nonretarded attraction has been demonstrated in a class of repulsively interacting electron systems that consist of a carrier band interacting with an insulting band.
Grant number：02102002

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Competitive research funding

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Competitive research funding

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UENO KeijiMaterial Science DivisionProfessorChemistry

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UENO　Keiji
Material Science Division Professor
Chemistry