Researcher basic information

• 博士（工学）, 北海道大学, Mar. 2008

• https://researchmap.jp/read0146924?lang=en

• https://jglobal.jst.go.jp/detail?JGLOBAL_ID=200901095124047349
• https://scholar.google.com/citations?user=KUBinl4AAAAJ&hl=ja

• 60519411

• 200901095124047349

• Thin film growth
• 結晶成長
• 量子構造
• ナノワイヤ
• 半導体物性
• 半導体デバイス物理

• Bachelor's degree program, School of Engineering
• Master's degree program, Graduate School of Information Science and Technology
• Doctoral (PhD) degree program, Graduate School of Information Science and Technology

Research activity information

• Oct. 2022, 北海道経産局, 第7回 NoMaps Dream Pitch 最優秀賞・NEDO賞・NICT賞
  燃えない近未来デバイス技術プラットフォーム
• Feb. 2022, 北海道, 北海道科学技術奨励賞
  半導体ナノワイヤ成長技術とその次世代電子デバイスへの応用
• Dec. 2017, MRS, Symposium Best Paper Award
  International society
• Apr. 2017, 公益財団法人 船井情報科学振興財団, 第16回船井学術賞
  冨岡 克広
• Dec. 2016, The JSPS Prize
  Tomioka Katsuhiro
• Sep. 2016, 国際固体素子・材料国際会議論文賞(SSDM Paper Award)
• Feb. 2016, 国立大学法人 北海道大学, 平成27年度 研究総長賞(奨励賞)
  冨岡 克広
• Nov. 2015, 東北大学 電気通信研究所（RIEC）, 第5回 RIEC Award
  冨岡 克広
• Nov. 2015, 一般財団法人 エヌエフ基金, 研究開発奨励賞優秀賞
  冨岡 克広
• Oct. 2015, 一般財団法人 エヌエフ基金, 研究開発奨励賞
  冨岡 克広
• Apr. 2015, 文部科学省, 科学技術分野の文部科学大臣表彰・若手科学者賞
  冨岡克広
• Jun. 2014, 一般財団法人 安藤研究所, 第27回安藤研究所研究奨励賞
  冨岡克広
• Mar. 2014, 一般財団法人 丸文財団, 第17回丸文研究奨励賞
  冨岡克広
• Feb. 2014, 電子情報通信学会, エレクトロニクスソサイエティ招待論文賞
  冨岡克広
• Sep. 2010, Japan Science and Applied Physics, Young Scientist Oral Presentation Award
  MOVPE選択成長法と再成長によるシリコン基板上のGaAs/InAs/GaAsナノワイヤ量子井戸の作製
  Tomioka Katsuhiro
• Aug. 2009, MRS 2009 spring meeting Session Best poster award
• Jul. 2009, IWPSN Committee, International Workshop on Photon and Spins in Nanostructure (IWPSN) Best Poster Award
  冨岡克広

• Selective-Area Growth of Large-Area Wurtzite InP Nanofin Arrays: Implications for Solid-State Lighting
  Yuki Azuma; Ziye Zheng; Junichi Motohisa; Katsuhiro Tomioka
  ACS Applied Nano Materials, 8, 39, 18734, 18739, American Chemical Society (ACS), 25 Sep. 2025, [Peer-reviewed], [Last author, Corresponding author]
  Scientific journal
• Origin of performance degradation in vertical gate-all-around transistors using vertical InGaAs nanowires on SOI(111) substrates
  Keita Taniyama; Yuki Takeda; Yuki Azuma; Ziye Zheng; Katsuhiro Tomioka
  Japanese Journal of Applied Physics, 64, 4, 04SP62, 04SP62, IOP Publishing, 01 Apr. 2025, [Peer-reviewed], [Last author]
  Scientific journal, Abstract
  
  Selective-area growth of InGaAs nanowires (NWs) and vertical gate-all-around (VGAA) transistors using the vertical InGaAs NWs on Silicon-on-insulator (SOI) substrates were characterized toward future three-dimensional integrated circuit applications using III-V NW-based VGAA transistors. On an n-type SOI, the VGAA transistor acts as a field-effect transistor (FET), involving carrier transport and the electrostatic modulation inside the InGaAs NW channels. While on a p-type SOI, the transistor exhibited tunnel FET properties, involving tunnel transport at the InGaAs NW/SOI interface. Characterization of the VGAA transistors with the variation of NW diameter revealed that device properties, including off-leakage current and subthreshold slope, were degraded with large NW diameter due to misfit dislocation at the NW/Si interface.
• InP Crystal Phase Heterojunction Transistor with a Vertical Gate-All-Around Structure
  Yu Katsumi; Hironori Gamo; Junichi Motohisa; Katsuhiro Tomioka
  ACS Applied Materials and Interfaces, 16, 23, 30471, 30477, American Chemical Society (ACS), 31 May 2024, [Peer-reviewed]
  Scientific journal
• Size control of InP nanowires by in situ annealing and its application to the formation of InAsP quantum dots
  Masahiro Sasaki; Tomoya Akamatsu; Katsuhiro Tomioka; Junichi Motohisa
  Nanotechnology, 35, 19, 195604, 195604, IOP Publishing, 20 Feb. 2024
  Scientific journal, Abstract
  
  We carried out in situ annealing of InP nanowires (NWs) in a metal-organic vapor phase epitaxial (MOVPE) growth reactor to control and reduce the tip size of InP NWs. InP NWs were grown by selective-area (SA) MOVPE on partially masked (111)A InP substrates, and annealing was successively applied in tertiarybutylphosphine (TBP) ambient. Initially, the InP NWs had a hexagonal cross-section with $\{11\bar{2}\}$ facets vertical to the substrates; they became tapered, and the edges were rounded by annealing. By appropriately selecting the annealing temperature and initial NW diameter, the tip size of the NW was reduced and NWs with a tip size of 20 nm were successfully formed. Subsequently, a thin InAsP layer was grown on the annealed NWs and their photoluminescence was investigated at low temperatures. The characterization results indicated the formation of InAsP quantum dots (QDs) emitting in the telecom band. Our approach is useful for reducing the size of the NWs and for the controlled formation of InAsP QDs embedded in InP NWs in photonic devices compatible with telecom bands.
• Characterization of nanowire light-emitting diodes with InP/InAsP heterostructures emitting in telecom band
  Junichi Motohisa; Akamatsu Tomoya; Okamoto Manami; Tomioka Katsuhiro
  Japanese Journal of Applied Physics, 63, 3, 03SP08, 03SP08, IOP Publishing, 08 Feb. 2024
  Scientific journal, Abstract
  
  We report the growth and characterization of InP/InAsP/InP nanowires (NWs) and NW LEDs (NW-LEDs), which emit light at telecom wavelengths. InP-based NWs were grown by selective-area metal-organic vapor-phase epitaxy, and a thin InAsP layer was embedded in the NWs. The NW exhibited emission lines in their low-temperature photoluminescence spectra, suggesting the formation of quantum dots (QDs) in the NW. NW-LED operation was demonstrated at both room and low temperatures in the telecom band, but it was found that the emission wavelength range and blueshift behavior induced by current injection differed considerably between room and low temperatures. Our results suggest that an efficient path for carrier injection into the active InAsP layer should be explored for NW-QD-based single-photon sources operating via current-injection.
• Selective-Area Growth of Vertical InGaAs/GaSb Core–Shell Nanowires on Silicon and Dual Switching Properties
  Hironori Gamo; Chen Lian; Junichi Motohisa; Katsuhiro Tomioka
  ACS Nano, American Chemical Society (ACS), 24 Aug. 2023, [Peer-reviewed]
  Scientific journal
• Enhanced Light Extraction of Nano‐Light‐Emitting Diodes with Metal‐Clad Structure Using Vertical GaAs/GaAsP Core–Multishell Nanowires on Si Platform
  Katsuhiro Tomioka; Kazuharu Sugita; Junichi Motohisa
  Advanced Photonics Research, 4, 7, Wiley, 20 Apr. 2023, [Peer-reviewed], [Lead author]
  Scientific journal, Nanometer‐scaled light sources using III–V compound semiconductor nanowires (NWs) on Si are expected as building blocks for next‐generation Si photonics, bioimaging, on‐chip microscopy, and light detection and ranging (LiDAR) techniques. This is, however, limited in a few materials systems due to complexity in integration of the vertical III–V NWs on Si and device process flow. Suppressing optical loss in the NW materials beyond the optical diffraction remains difficult in enhancing light extraction. Herein, the effect of the vertical metal‐clad architectures for the vertical nano‐light‐emitting diodes (LEDs) using GaAs/GaAsP‐related core–multishell NWs heterogeneously integrated on Si is investigated. The grown core–multishell NW is composed of a radial n‐GaAs/n‐GaAsP/p‐GaAs/p‐GaAsP double heterostructure. The vertical metal‐clad NW‐LEDs show suppression of carrier overflow effect and rapid enhancement of electrical luminescence.
• Current injection and luminescence properties of wurtzite InP nanowires with crystal phase transition
  Yuki Azuma; Shun Kimura; Hironori Gamo; Junichi Motohisa; Katsuhiro Tomioka
  Japanese Journal of Applied Physics, 62, SC, SC1011, SC1011, IOP Publishing, 30 Dec. 2022, [Peer-reviewed]
  Scientific journal, Abstract
  
  We characterized the current injection and electroluminescence (EL) properties of wurtzite (WZ) InP nanowire (NW) light-emitting diodes (LEDs) with axial junctions. The EL spectra of two samples with the same LED junction structure exhibited two different behaviors. One showed a single EL peak originating from the zinc-blende (ZB)-InP bandgap. The other showed two EL peaks originating from the ZB and WZ phases. This difference in EL behavior is attributed to the difference in the contact position and to depletion layer spreading. Clarification of the origin of the different EL peaks is important for optimizing the NW-LED structure.
• InP nanowire light-emitting diodes with different pn-junction structures
  S Kimura; H Gamo; Y Katsumi; J Motohisa; K Tomioka
  Nanotechnology, 33, 30, 305204, May 2022, [Peer-reviewed], [Last author]
  English, Scientific journal
• Creation of unexplored tunnel junction by heterogeneous integration of InGaAs nanowires on germanium
  Akinobu Yoshida; Hironori Gamo; Junichi Motohisa; Katsuhiro Tomioka
  Scientific Reports, 12, 1, Springer Science and Business Media LLC, Dec. 2021, [Peer-reviewed], [Corresponding author]
  Scientific journal, Heteroepitaxy has inherent concerns regarding crystal defects originated from differences in lattice constant, thermal expansion coefficient, and crystal structure. The selection of III–V materials on group IV materials that can avoid these issues has however been limited for applications such as photonics, electronics, and photovoltaics. Here, we studied nanometer-scale direct integration of InGaAs nanowires (NWs) on Ge in terms of heterogenous integration and creation of functional materials with an as yet unexplored heterostructure. We revealed that changing the initial Ge into a (111)B-polar surce anabled vertical InGaAs NWs to be integrated for all In compositions examined. Moreover, the growth naturally formed a tunnel junction across the InGaAs/Ge interface that showed a rectification property with a huge current density of several kAcm⁻² and negative differential resistance with a peak-to-valley current ratio of 2.8. The described approach expands the range of material combinations for high-performance transistors, tandem solar cells, and three-dimensional integrations.
• Scaling effect on vertical gate-all-around FETs using III-V NW-channels on Si
  Katsuhiro Tomioka; Junichi Motohisa
  IEEE SNW 2021 Tech. Dig., 51, 52, Jun. 2021, [Peer-reviewed]
• A logical switch to the vertical direction
  Katsuhiro Tomioka
  Compound Semiconductor, V, 40, 45, May 2021, [Peer-reviewed], [Invited], [Lead author]
  English, Research society
• Vertical Gate-All-Around Tunnel FETs Using InGaAs Nanowire/Si with Core-Multishell Structure
  Katsuhiro Tomioka; Hironori Gamo; Junichi Motohisa; Takashi Fukui
  2020 IEEE International Electron Devices Meeting (IEDM), IEEE, 12 Dec. 2020, [Peer-reviewed], [Lead author]
  English, International conference proceedings
• Rational synthesis of atomically thin quantum structures in nanowires based on nucleation processes
  Katsuhiro Tomioka; Junichi Motohisa; Takashi Fukui
  Scientific Reports, 10, 1, Springer Science and Business Media LLC, Dec. 2020, [Peer-reviewed], [Lead author]
  Scientific journal
• Demonstration of InP/InAsP/InP axial heterostructure nanowire array vertical LEDs
  Tomoya Akamatsu; Katsuhiro Tomioka; Junichi Motohisa
  Nanotechnology, 31, 39, 394003, 394003, IOP Publishing, 25 Sep. 2020, [Peer-reviewed]
  Scientific journal
• Selective-Area Growth of AlInAs Nanowires
  Yoshiki Tai; Hironori Gamo; Junichi Motohisa; Katsuhiro Tomioka
  ECS Transactions, 98, 6, 149, 153, The Electrochemical Society, 23 Sep. 2020, [Peer-reviewed], [Last author]
  English, Scientific journal
• InGaAs-InP core–shell nanowire/Si junction for vertical tunnel field-effect transistor
  Katsuhiro Tomioka; Fumiya Ishizaka; Junichi Motohisa; Takashi Fukui
  Applied Physics Letters, 117, 12, 123501, 123501, AIP Publishing, 21 Sep. 2020, [Peer-reviewed], [Lead author]
  English, Scientific journal
• Integration of Indium Arsenide/Indium Phosphide Core-Shell Nanowire Vertical Gate-All-Around Field-Effect Transistors on Si
  Hironori Gamo; Katsuhiro Tomioka
  IEEE Electron Device Letters, 41, 8, 1169, 1172, Institute of Electrical and Electronics Engineers (IEEE), Aug. 2020, [Peer-reviewed], [Last author]
  Scientific journal
• Vertical Tunnel FET Technologies Using III-V/Si Heterojunction
  K.Tomioka; H. Gamo; J. Motohisa
  ECS Transactions, 92, 4, 71, 78, Oct. 2019, [Peer-reviewed]
  English
• III-V族化合物半導体ナノワイヤトランジスタ集積技術 (解説)
  冨岡 克広
  応用物理, 88, 4, 245, 251, Apr. 2019, [Peer-reviewed], [Invited], [Lead author, Corresponding author]
  Japanese, Scientific journal
• Characterization of nanowire light-emitting diodes grown by selective-area metal-organic vapor-phase epitaxy
  J. Motohisa; H. Kameda; M. Sasaki; K. Tomioka
  Nanotechnology, 30, 13, 134002, 134002, IOP Publishing, Mar. 2019, [Peer-reviewed]
  Scientific journal
• Vertical InGaAs Nanowire Array Photodiodes on Si
  K. Chiba; A. Yoshida; K. Tomioka; J. Motohisa
  ACS PHOTONICS, 6, 2, 260, 264, American Chemical Society (ACS), Feb. 2019, [Peer-reviewed]
  Scientific journal
• Preface for Recent Progress in Nanowire Growth
  Tomioka Katsuhiro; Akiyama Toru; Katayama Ryuji
  Journal of the Japanese Association for Crystal Growth, 46, 2, n/a, The Japanese Association for Crystal Growth, 2019
  Japanese
• Growth and characterization of GaAs nanowires on Ge(111) substrates by selective-area MOVPE
  Yusuke Minami; Akinobu Yoshida; Junichi Motohisa; Katsuhiro Tomioka
  J. Cryst. Growth, 506, 135, 139, Oct. 2018, [Peer-reviewed]
  English
• Selective-area growth of pulse-doped InAs nanowires on Si and vertical transistor application
  Hironori Gamo; Katsuhiro Tomioka
  J. Cryst. Growth, 500, 58, 62, Oct. 2018, [Peer-reviewed]
  English
• Composition controllability of InGaAs nanowire arrays in selective area growth with controlled pitches on Si platform
  Kohei Chiba; Katsuhiro Tomioka; Akinobu Yoshida; Junichi Motohisa
  AIP ADVANCES, 7, 12, 125304 – 1, 125304 – 5, Dec. 2017, [Peer-reviewed]
  English, Scientific journal
• Composition controllability of InGaAs nanowire arrays in selective area growth with controlled pitches on Si platform
  Kohei Chiba; Katsuhiro Tomioka; Akinobu Yoshida; Junichi Motohisa
  AIP Advances, 7, 125304, Dec. 2017, [Peer-reviewed]
  English, Scientific journal
• (Invited) Transistor application using vertical III-V nanowires on Si platform
  Katsuhiro Tomioka; Takashi Fukui
  ECS Transaction, 80, 43, 52, Oct. 2017, [Peer-reviewed], [Invited]
  English
• Growth of All-Wurtzite InP/AlInP Core–Multishell Nanowire Array
  Fumiya Ishizaka; Yoshihiro Hiraya; Katsuhiro Tomioka; Junithic Motohisa; Takashi Fukui
  Nano Lett., 17, 1350, 1355, Feb. 2017, [Peer-reviewed]
  English, Scientific journal
• III-V Nanowires: Transistor and photovoltaic applications
  Katsuhiro Tomioka; Junichi Motohisa; Takashi Fukui
  Novel Compound Semiconductor Nanowires: Materials, Devices, and Applications, 465, 516, Pan Stanford Publishing Pte. Ltd., 01 Jan. 2017
  English, In book
• Growth of InGaAs nanowires on Ge(111) by selective-area metal-organic vapor phase epitaxy
  A. Yoshida; K. Tomioka; F. Ishizaka; J. Motohisa
  J. Cryst. Growth, 464, 75, 79, Jan. 2017, [Peer-reviewed]
  English, Scientific journal
• Growth and characterization of wurtzite InP/AlGaP core–multishell nanowires with AlGaP quantum well structures
  Fumiya Ishizaka; Yoshihiro Hiraya; Katsuhiro Tomioka; Junichi Motohisa; Takashi Fukui
  Jpn. J. Appl. Phys., 56, 1, 010311, 10311, Institute of Physics, Dec. 2016, [Peer-reviewed]
  English, Scientific journal, We report on the selective-area growth and characterization of wurtzite (WZ) InP/AlGaP core–multishell nanowires. Quantum well (QW) structures were fabricated in AlGaP multishells by changing the alloy composition. Transmission electron microscopy revealed that the AlGaP multishells were grown with a WZ structure on the side of the WZ InP core. The lattice constants of the WZ InP core and WZ AlGaP shell were determined by X-ray diffraction. Cathodoluminescence studies showed that the WZ AlGaP QW with an Al composition of 20% exhibited green emissions at 2.37 eV. These results open the possibility of fabricating green light-emitting diodes using WZ AlGaP-based materials.
• (Invited) Recent Progress in Vertical Si/III-V Tunnel FETs: From Fundamentals to Current-Boosting Technology
  Katsuhiro Tomioka; Junichi Motohisa; Takashi Fukui
  ECS Transaction, 75, 5, 127, 134, The Electrochemical Society (ECS), Sep. 2016, [Peer-reviewed], [Invited]
  English, International conference proceedings, Tunnel field-effect transistors (TFETs) with a steep subthreshold-slope (SS) are promising low-power switches for future large-scale integrated circuits (LSIs) with low power consumption and high performance. Recently, we demonstrated vertical TFETs with III-V/Si heterojunctions. This new sort of tunnel junction achieves a steep SS because of its unique figure-of-merit. Here, we report on recent progress on vertical TFETs using Si/III-V heterojunctions and means for boosting on-state current.
• Selective-Area Growth of Vertical InGaAs Nanowires on Ge for Transistor Applications
  Akinobu Yoshida; Katsuhiro Tomioka; Fumiya Ishizaka; Kohei Chiba; Junichi Motohisa
  ECS Transaction, 75, 7, 265, 270, The Electrochemical Society (ECS), Sep. 2016, [Peer-reviewed]
  English, International conference proceedings, III-V compound semiconductors and Ge are promising futurechannel materials because of their high carrier mobility. Forexample the electron mobility of InAs is about 20 times faster thanthat of Si at room temperature and hole mobility of Ge is about 5times faster than that of Si. In this paper, we report directintegration of InGaAs nanowires (NWs) on Ge(111) substrate byselective-area metal organic vapor phase epitaxy (SA-MOVPE) forrealization of high carrier mobility InGaAs/Ge hybrid CMOSapplications, and characterization of the composition and growthmodes of InGaAs NWs by X-ray diffraction (XRD) measurement.
• Crystal phase transition to green emission wurtzite AlInP by crystal structure transfer
  Y. Hiraya; F. Ishizaka; K. Tomioka; T. Fukui
  Applied Physics Express, 9, 3, 035502-1, 4, Institute of Physics, Feb. 2016, [Peer-reviewed]
  English, We grew AlInP on two types of GaN substrate in order to transfer the wurtzite (WZ) structure to grown layers. An AlInP epitaxial layer grown on GaN[Formula: see text] with high-density stacking faults was obtained. X-ray diffraction and Raman scattering analyses indicate that the dominant crystal structure of the AlInP layer grown on GaN[Formula: see text] was WZ. Cathode luminescence measurements at 35 K revealed strong green emissions from the WZ AlInP layer, suggesting an energy band gap change from indirect to direct. These results demonstrate the potential of WZ AlInP as a new candidate for high-efficiency green emission material.
• Flat transistor defies hte limit
  Katsuhiro Tomioka
  Nature Digest, 13, 1, 36, 37, Springer Science and Business Media LLC, Jan. 2016, [Peer-reviewed], [Invited], [Corresponding author]
  Japanese, Research society
• Selective-area growth of InGaAs/InP/InAlAs/InP core-multishell nanowires on Si and tunneling transistor application
  Katsuhiro Tomioka; Fumiya Ishizaka; Junichi Motohisa; Takashi Fukui
  2016 COMPOUND SEMICONDUCTOR WEEK (CSW) INCLUDES 28TH INTERNATIONAL CONFERENCE ON INDIUM PHOSPHIDE & RELATED MATERIALS (IPRM) & 43RD INTERNATIONAL SYMPOSIUM ON COMPOUND SEMICONDUCTORS (ISCS), 2016, [Peer-reviewed]
  English, International conference proceedings
• Advances in Steep-Slope Tunnel FETs
  Katsuhiro Tomioka; Junichi Motohisa; Takashi Fukui
  2016 46TH EUROPEAN SOLID-STATE DEVICE RESEARCH CONFERENCE (ESSDERC), 397, 402, 2016, [Peer-reviewed], [Invited]
  English, International conference proceedings
• Flat transistor defies limit
  Katsuhiro Tomioka
  Nature, 526, 51, 52, Oct. 2015, [Peer-reviewed], [Invited]
  English, Scientific journal
• Selective-area growth of InAs nanowires on Ge and vertical transistor application
  K. Tomioka; F. Ishizaka; T. Fukui
  Nano Letters, 15, 7253, 7257, Oct. 2015, [Peer-reviewed]
  English, Scientific journal
• Surrounding-Gate Tunnel FET Using InAs/Si Heterojunction
  K. Tomioka; J. Motohisa; T. Fukui
  ECS Trans., 169, 109, 118, Oct. 2015, [Peer-reviewed]
  English, International conference proceedings
• III-V nanowire channel on Si: From high-performance vertical FET to steep-slope devices
  Katsuhiro Tomioka; Junichi Motohisa; Takashi Fukui
  International Symposium on VLSI Technology, Systems, and Applications, Proceedings, 2015-, Institute of Electrical and Electronics Engineers Inc., 03 Jun. 2015, [Peer-reviewed]
  English, International conference proceedings
• Growth of wurtzite GaP in InP/GaP core-shell nanowires by selective-area MOVPE
  Ishizaka Fumiya; Hiraya Yoshihiro; Tomioka Katsuhiro; Fukui Takashi
  Journal of crystal growth, 411, 71, 75, Elsevier, Feb. 2015, [Peer-reviewed]
  English, A GaP nanowire is promising from the viewpoint of device applications because when its crystal phase is changed from zinc blende (ZB) to wurtzite (WZ), its band gap changes from indirect to direct. GaP in the WZ phase is theoretically and experimentally shown to have the possibility of "green" emission. Here we report on the growth of WZ GaP in InP/GaP core-shell nanowires by selective-area metal-organic vapor-phase epitaxy (SA-MOVPE). WZ InP nanowires were used as a template for transferring the WZ structure to GaP. Transmission electron microscopy revealed that WZ GaP was grown on the sidewalls of the InP core in the lateral <-2 1 1 > direction and that ZB GaP was grown on the top of the le core in the axial < 1 1 1 > A direction. A growth model for the different crystal structures of the GaP shell is proposed from the viewpoint of the growth direction. The WZ structure is "transferred" from the InP core to the GaP shell only when GaP grows in the direction perpendicular to the WZ stacking direction of the InP core. This so-called "crystal structure transfer" can also be applied to p- and n-doped GaP and is therefore promising for fabricating WZ-GaP-basecl light-emitting diodes. (C) 2014 Elsevier B.V. All rights reserved.
• Application of free-standing InP nanowire arrays and their optical properties for resource-saving solar cells
  Chen Muyi; Nakai Eiji; Tomioka Katsuhiro; Fukui Takashi
  Appl. Phys. Express, 8, 1, 012301, 12301, Institute of Physics, Jan. 2015, [Peer-reviewed]
  English, III–V compound semiconductor nanowire (NW) arrays have exhibited remarkable behavior in photovoltaic applications. We embedded an orderly vertical InP NW array in poly(dimethylsiloxane) (PDMS) and peeled it off from the substrate to form a AuZn contact. The sample with the substrate exhibited a very high average absorptance of 92%. However, when the array was peeled off, the optical absorptance degraded, particularly in the longer-wavelength region. After the AuZn was deposited on the back side of the NW array, the absorptance increased. This technology could enable a new approach for NW-based photovoltaics with a lower fabrication cost.
• InGaAs axial-junction nanowire-array solar cells
  Eiji Nakai; Muyi Chen; Masatoshi Yoshimura; Katsuhiro Tomioka; Takashi Fukui
  Japanese Journal of Applied Physics, 54, 1, 015201, 015201, IOP Publishing, 01 Jan. 2015, [Peer-reviewed]
  English, Scientific journal, Axial p–i–n junction nanowire (NW) solar cells (SCs) with a position-controlled GaAs-based NW array were fabricated by selective-area metal organic vapor phase epitaxy (SA-MOVPE). The measured electron-beam-induced current (EBIC) signals showed the formation of an axial p–i–n junction, which confirms power generation under sunlight illumination. The series resistance of the NW SCs is much higher than that of conventional planar SCs based on Si or other III–V compound semiconductors. The main difficulty concerning the fabrication of these NW SCs is the degradation of series resistance between the GaAs-based NWs and the indium–tin oxide (ITO) deposited as a transparent electrode. The series resistance of the fabricated GaAs-based NW SCs was reduced by introducing a tin doping contact layer between the ITO and the NW array, which is formed by pulse doping. As a result of this improved structure, the fabricated SCs exhibited an open-circuit voltage of 0.544 V, a short-circuit current of 18.2 mA/cm², and a fill factor of 0.721 for an overall conversion efficiency of 7.14% under AM1.5G illumination. The series resistance of the SCs could be decreased to 0.132 Ω·cm², which is one order of magnitude lower than that of the SC without a highly doped contact layer. This reduced series resistance indicates that nanostructure SCs with transparent electrodes and multijunction NW SCs with high efficiencies can be fabricated on a commercial basis in the near future.
• Growth of Semiconductor Nanocrystals
  Katsuhiro Tomioka; Takashi Fukui
  Handbook of Crystal Growth: Second Edition, 1, 749, 793, Elsevier Inc., 24 Dec. 2014, [Peer-reviewed]
  English, In book
• Recent progress in integration of III-V nanowire transistors on Si substrate by selective-area growth
  Katsuhiro Tomioka; Takashi Fukui
  JOURNAL OF PHYSICS D-APPLIED PHYSICS, 47, 39, 364001, Oct. 2014, [Peer-reviewed]
  English, Scientific journal
• III-V族化合物半導体ナノワイヤ太陽電池
  福井 孝志; 吉村 正利; 中井 栄治; 冨岡 克広
  日本結晶成長学会誌, 41, 2, 29, 34, Jul. 2014, [Peer-reviewed], [Invited]
  Japanese, Scientific journal
• Vertical Tunnel FETs Using III-V Nanowire/Si Heterojunctions
  Katsuhiro Tomioka; Takashi Fukui
  ECS Trans., 61, 81, May 2014, [Peer-reviewed]
• Current increment of tunnel field-effect transistor using InGaAs nanowire/Si heterojunction by scaling of channel length
  Katsuhiro Tomioka; Takashi Fukui
  Applied Physics Letters, 104, 7, 073507, 73507, American Institute of Physics, Feb. 2014, [Peer-reviewed]
  English, Scientific journal, We report on a fabrication of tunnel field-effect transistors using InGaAs nanowire/Si heterojunctions and the characterization of scaling of channel lengths. The devices consisted of single InGaAs nanowires with a diameter of 30 nm grown on p-type Si(111) substrates. The switch demonstrated steep subthreshold-slope (30 mV/decade) at drain-source voltage (V-DS) of 0.10 V. Also, pinch-off behavior appeared at moderately low VDS, below 0.10 V. Reducing the channel length of the transistors attained a steep subthreshold slope (< 60 mV/decade) and enhanced the drain current, which was 100 higher than that of the longer channels. (C) 2014 AIP Publishing LLC.
• Indium tin oxide and indium phosphide heterojunction nanowire array solar cells
  Masatoshi Yoshimura; Eiji Nakai; Katsuhiro Tomioka; Takashi Fukui
  Applied Physics Letters, 103, 24, 243111, 243111, American Institute of Physics, Dec. 2013, [Peer-reviewed]
  English, Scientific journal, Heterojunction solar cells were formed with a position-controlled InP nanowire array sputtered with indium tin oxide (ITO). The ITO not only acted as a transparent electrode but also as forming a photovoltaic junction. The devices exhibited an open-circuit voltage of 0.436 V, short-circuit current of 24.8 mA/cm(2), and fill factor of 0.682, giving a power conversion efficiency of 7.37% under AM1.5G illumination. The internal quantum efficiency of the device was higher than that of the world-record InP cell in the short wavelength range. (C) 2013 AIP Publishing LLC.
• Sub 60 mV/decade Switch Using an InAs Nanowire-Si Heterojunction and Turn-on Voltage Shift with a Pulsed Doping Technique
  Katsuhiro Tomioka; Masatoshi Yoshimura; Takashi Fukui
  Nano Letters, 13, 12, 5822, 5826, Dec. 2013, [Peer-reviewed]
  English, Scientific journal
• Vertical III-V Nanowire-Channel on Si
  Katsuhiro Tomioka; Takashi Fukui
  ECS Transaction, 58, 7, 99, 114, Oct. 2013, [Peer-reviewed], [Invited]
  English, International conference proceedings
• GaAs/InGaP Core-Multishell Nanowire-Array-Based Solar Cells
  Eiji Nakai; Masatoshi Yoshimura; Katsuhiro Tomioka; Takashi Fukui
  JAPANESE JOURNAL OF APPLIED PHYSICS, 52, 5, UNSP 055002, 055002-4, The Japan Society of Applied Physics, May 2013, [Peer-reviewed]
  English, Scientific journal, Semiconductor nanowires (NWs) are good candidate for light-absorbing material in next generation photovoltaic and III--V NW-based multi-heterojunction solar cells using lattice-mismatched material system are expected as high energy-conversion efficiencies under concentrated light. Here we demonstrate core--shell GaAs NW arrays by using catalyst-free selective-area metal organic vapor phase epitaxy (SA-MOVPE) as a basis for multijunction solar cells. The reflectance of the NW array without any anti-reflection coating showed much lower reflection than that of a planar wafer. Next we then fabricated core--shell GaAs NW array solar cells with radial p--n junction. Despite the low reflectance, the energy-conversion efficiency was 0.71% since a high surface recombination rate of photo-generated carriers and poor ohmic contact between the GaAs and transparent indium--tin-oxide (ITO) electrode. To avoid these degradations, we introduced an InGaP layer and a Ti/ITO electrode. As a result, we obtained a short-circuit current of 12.7 mA cm^-2, an open-circuit voltage of 0.5 V, and a fill factor of 0.65 for an overall efficiency of 4.01%.
• Indium Phosphide Core-Shell Nanowire Array Solar Cells with Lattice-Mismatched Window Layer
  Masatoshi Yoshimura; Eiji Nakai; Katsuhiro Tomioka; Takashi Fukui
  Applied Physics Express, 6, 5, 052301, 052301-4, The Japan Society of Applied Physics, May 2013, [Peer-reviewed]
  English, Scientific journal, We report surface-passivated core--shell InP nanowire array solar cells fabricated using catalyst-free selective-area metal organic vapor phase epitaxy. Reflectance measurements confirm enhanced light absorption due to significantly reduced reflectance over a wide spectral range. The wide-band-gap outer shell layer of core-multishell nanowires effectively passivates the large surface area of the nanowires, increasing the short-circuit current density and elevating the energy conversion efficiency by 6.35% under AM1.5G illumination. This passivation technique could open a new approach to nanowire-based photovoltaics with higher energy efficiency.
• Indium Phosphide core-shell nanowire solar cells with wide bandgap window layer
  M. Yoshimura; E. Nakai; K. Tomioka; T. Fukui
  Applied Physics Express, 6, 052301-1, 4, May 2013, [Peer-reviewed]
  English
• Indium-Rich InGaP Nanowires Formed on InP (111)A Substrates by Selective-Area Metal Organic Vapor Phase Epitaxy
  F. Ishizaka; K. Ikejiri; K.Tomioka; T. Fukui
  Japanese Journal of Applied Physics, 52, 4, UNSP 04CH05, 04CH05-4, The Japan Society of Applied Physics, Apr. 2013, [Peer-reviewed]
  English, International conference proceedings, We studied the growth of indium-rich InGaP nanowires (NWs) on InP (111)A substrates by selective-area metal organic vapor phase epitaxy (SA-MOVPE). We obtained vertically aligned InGaP NWs by optimizing growth conditions, such as group III supply ratio and V/III ratio. We found that the height, diameter, shape, and composition of InGaP NWs depended significantly on the supply ratios of trimethylgallium (TMGa) and trimethylindium (TMIn). As the supply ratio of TMGa was increased, the lateral growth was drastically enhanced, and the uniformity of NWs deteriorated. Furthermore, the sidewall facets of NWs changed from \{\bar{2}11\} to \{\bar{1}10\} as the supply ratio of TMGa was increased, indicating the possibility of structural transition from wurtzite (WZ) to zinc blende (ZB). We propose a possible growth model for such lateral growth, uniformity, and structural transition. Photoluminescence (PL) measurements revealed that the Ga compositions ranged approximately from 0 to 15%. Our results show that highly uniform InGaP NWs can be grown by controlling the growth conditions.
• GaAs nanowire growth on polycrystalline silicon thin films using selective-area MOVPE
  Keitaro Ikejiri; Fumiya Ishizaka; Katsuhiro Tomioka; Takashi Fukui
  Nanotechnology, 24, 11, 115304, IOP Publishing, Mar. 2013, [Peer-reviewed]
  English, Scientific journal, The growth mechanism of GaAs nanowires (NWs) grown on polycrystalline silicon (poly-Si) thin films using selective-area metalorganic vapor-phase epitaxy was investigated. Wire structures were selectively grown in the mask openings on a poly-Si substrate. The appearance ratio of wire structures strongly depended on the growth conditions and deposition temperature of the poly-Si substrate. Evaluation of the grown shapes and growth characteristics revealed that GaAs NWs grown on a poly-Si substrate have the same growth mechanism as conventional GaAs NWs grown on a single-crystalline GaAs or Si substrate. Experiments showed that the wire structure yield can be improved by increasing the Si grain size and/or increasing the Si deposition temperature. The growth model proposed for understanding NW growth on poly-Si is based on the mask opening size, the Si grain size, and the growth conditions. The ability to control the growth mode is promising for the formation of NWs with complex structures on poly-Si thin layers.
• Gate-first process and EOT-scaling of III-V nanowire-based vertical transistors on Si
  Katsuhiro Tomioka; Takashi Fukui
  2013 71ST ANNUAL DEVICE RESEARCH CONFERENCE (DRC), 15, +, 2013, [Peer-reviewed]
  English, International conference proceedings
• III-V compound semiconductor nanowire solar cells
  Takashi Fukui; Masatoshi Yoshimura; Eiji Nakai; Katsuhiro Tomioka
  CLEO: Science and Innovations, CLEO_SI 2013, CTh1M.3, 2013
  English, International conference proceedings
• Integration of III-V nanowires on Si: From high-performance vertical FET to steep-slope switch
  Katsuhiro Tomioka; Masatoshi Yoshimura; Eiji Nakai; Fumiya Ishizaka; Takashi Fukui
  Technical Digest - International Electron Devices Meeting, IEDM, 4.1.4, 2013, [Peer-reviewed]
  English, International conference proceedings
• III-V/Si heterojunctions for steep subthreshold-slope transistor
  Katsuhiro Tomioka; Takashi Fukui
  2013 THIRD BERKELEY SYMPOSIUM ON ENERGY EFFICIENT ELECTRONIC SYSTEMS (E3S), 2013, [Peer-reviewed]
  English, International conference proceedings
• Bidirectional Growth of Indium Phosphide Nanowires
  Keitaro Ikejiri; Fumiya Ishizaka; Katsuhiro Tomioka; Takashi Fukui
  Nano Letters, 12, 9, 4770, 4774, Sep. 2012, [Peer-reviewed]
  English, Scientific journal
• A III–V nanowire channel on silicon for high-performance vertical transistors
  Katsuhiro Tomioka; Masatoshi Yoshimura; Takashi Fukui
  Nature, 488, 7410, 189, 192, Aug. 2012, [Peer-reviewed]
  English, Scientific journal
• Vibrational modes of GaAs hexagonal nanopillar arrays studied with ultrashort optical pulses
  Hirotaka Sakuma; Motonobu Tomoda; Paul H. Otsuka; Osamu Matsuda; Oliver B. Wright; Takashi Fukui; Katsuhiro Tomioka; Istvan A. Veres
  APPLIED PHYSICS LETTERS, 100, 13, Mar. 2012, [Peer-reviewed]
  English, Scientific journal
• Position-Controlled III-V Compound Semiconductor Nanowire Solar Cells by Selective-Area Metal-Organic Vapor Phase Epitaxy
  Takashi Fukui; Masatoshi Yoshimura; Eiji Nakai; Katsuhiro Tomioka
  AMBIO, 41, 119, 124, Mar. 2012, [Peer-reviewed]
  English, Scientific journal
• Longitudinal and Transverse Exciton Spin Relaxation in Single InP/InAsP/InP Nanowire Quantum Dots
  H. Sasakura; C. Hermannstädter; S. N. Dorenbos; N. Akopian; M. P. van Kouwen; J. Motohisa; Y. Kobayashi; H. Kumano; K. Kondo; K. Tomioka; T. Fukui; I. Suemune; V. Zwiller
  Phys. Rev. B, 85, 075324, Feb. 2012, [Peer-reviewed]
  English, Scientific journal
• Longitudinal and transverse exciton-spin relaxation in a single InAsP quantum dot embedded inside a standing InP nanowire using photoluminescence spectroscopy
  Sasakura H.; Dorenbos S. N.; Akopian N.; van Kouwen M. P.; Motohisa J.; Kobayashi Y.; Kumano H.; Kondo K.; Tomioka K.; Fukui T.; Suemune I.; Zwiller V.
  Phys. Rev. B, 85, 7, 075324-1, 075324-7, American Physical Society, Feb. 2012, [Peer-reviewed]
  English, Scientific journal, We have investigated the optical properties of a single InAsP quantum dot embedded in a standing InP nanowire. Elongation of the transverse exciton-spin relaxation time of the exciton state with decreasing excitation power was observed by first-order photon correlation measurements. This behavior is well explained by the motional narrowing mechanism induced by Gaussian fluctuations of environmental charges in the nanowire. The longitudinal exciton-spin relaxation time is evaluated by the degree of the random polarization of emission originating from exciton states confined in a single-nanowire quantum dot by using Mueller calculus based on Stokes parameters representation. The reduction in the random polarization component with decreasing excitation power is caused by suppression of the exchange interaction of electron and hole due to an optically induced internal electric field by the dipoles at the wurtzite and zinc-blende heterointerfaces in the InP nanowire.
• III-V semiconductor nanowires on Si by selective-area metal-organic vapor phase epitaxy
  Katsuhiro Tomioka; Takashi Fukui
  NanoScience and Technology, 58, 67, 101, 2012, [Peer-reviewed]
  English, Scientific journal
• Steep-slope tunnel field-effect transistors using III-V nanowire/Si heterojunction
  Katsuhiro Tomioka; Masatoshi Yoshimura; Takashi Fukui
  Digest of Technical Papers - Symposium on VLSI Technology, 47, 48, 2012, [Peer-reviewed]
  English, International conference proceedings
• Advances in semiconductor nanowire devices
  Tomioka Katsuhiro; Takashi Fukui
  応用物理, 81, 1, 59, 64, Jan. 2012, [Peer-reviewed]
  Japanese, Scientific journal
• Influence of growth temperature on growth of InGaAs nanowires in selective-area metal-organic vapor-phase epitaxy
  Yoshinori Kohashi; Takuya Sato; Keitaro Ikejiri; Katsuhiro Tomioka; Shinjiroh Hara; Junichi Motohisa
  JOURNAL OF CRYSTAL GROWTH, 338, 1, 47, 51, Jan. 2012, [Peer-reviewed]
  English, Scientific journal
• Fabrication of axial and radial heterostructures for semiconductor nanowires by using selective-area metal-organic vapor-phase epitaxy
  K. Hiruma; K. Tomioka; P. Mohan; L. Yang; J. Noborisaka; B. Hua; A. Hayashida; S. Fujisawa; S. Hara; J. Motohisa; T. Fukui
  Journal of Nanotechnology, Vol. 2012, 169284-1, 169284-29, 2012, [Peer-reviewed], [Invited]
  English, Scientific journal
• Growth of InAs/InAlAs Core-Shell Nanowires on Si and Transistor Application
  Katsuhiro Tomioka; Tomotaka Tanaka; Takashi Fukui
  ECS Transactions, 41, 3, 61, 69, Nov. 2011, [Peer-reviewed]
  English, Scientific journal
• Selective-area growth of III-V nanowires and their applications
  Katsuhiro Tomioka; Keitaro Ikejiri; Tomotaka Tanaka; Junichi Motohisa; Shinjiroh Hara; Kenji Hiruma; Takashi Fukui
  Journal of the Material Society, 26, 17, 2127, 2141, Sep. 2011, [Peer-reviewed]
  English, Scientific journal
• III–V Nanowires on Si Substrate: Selective-Area Growth and Device Applications
  Katsuhiro Tomioka; Tomotaka Tanaka; Shinjiro Hara; Kenji Hiruma; Takashi Fukui
  IEEE Journal of Selected Topics in Quantum Electronics, 17, 4, 1112, 1129, Aug. 2011, [Peer-reviewed], [Invited]
  English, Scientific journal
• Zinc Blende and Wurtzite Crystal Phase Mixing and Transition in Indium Phosphide Nanowires
  Keitaro Ikejiri; Yusuke Kitauchi; Katsuhiro Tomioka; Junichi Motohisa; Takashi Fukui
  Nano Letters, 11, 10, 4314, 4318, Aug. 2011, [Peer-reviewed]
  English, Scientific journal
• Tunnel field-effect transistor using InAs nanowire/Si heterojunction
  Katsuhiro Tomioka; Takashi Fukui
  Applied Physics Letters, 98, 8, 083114, Feb. 2011, [Peer-reviewed]
  English, Scientific journal
• III-V semiconductor nanowire light emitting diodes and lasers
  Junichi Motohisa; Katsuhiro Tomioka; Bin Hua; Kumar S.K. Varadwaj; Shinjiroh Hara; Kenji Hiruma; Takashi Fukui
  Advances in III-V Semiconductor Nanowires and Nanodevices, 145, 157, Bentham Science Publishers Ltd., 2011, [Peer-reviewed]
  English, In book
• Vertical In0.7Ga0.3As Nanowire Surrounding-Gate Transistors with High-k Gate Dielectric on Si Substrate
  Katsuhiro Tomioka; Masatoshi Yoshimura; Takashi Fukui
  2011 IEEE INTERNATIONAL ELECTRON DEVICES MEETING (IEDM), 773, 776, 2011, [Peer-reviewed]
  English, International conference proceedings
• 23pRB-6 EXCITON POLARIZATION IN A SINGLE NANOWIRE QUANTM DOT
  Sasakura H; Kumano H; Suemune I; Dorenbos S. N; Kouwen M; P. van; Zwiller V; Kabayashi Y; Motohisa J; Tomioka K; Fukui T; Herm; stadter C
  Meeting Abstracts of the Physical Society of Japan, 66, 0, The Physical Society of Japan, 2011
  Japanese, Scientific journal
• Selective-area MOVPE of GaSb on GaAs (111)-oriented substrates
  Y. Takayama; K. Tomioka; S. Hara; T. Fukui; J. Motohisa
  physica status solidi c, 8, 2, 272, 274, Nov. 2010, [Peer-reviewed]
  English, Scientific journal
• Position controlled nanowires for infrared single photon emission
  S. N. Dorenbos; H. Sasakura; M. P. van Kouwen; N. Akopian; S. Adachi; N. Namekata; M. Jo; J. Motohisa; Y. Kobayashi; K. Tomioka; T. Fukui; S. Inoue; H. Kumano; C. M. Natarajan; R. H. Hadfield; T. Zijlstra; T. M. Klapwijk; V. Zwiller; I. Suemune
  APPLIED PHYSICS LETTERS, 97, 17, 171106, Oct. 2010, [Peer-reviewed]
  English, Scientific journal
• Lattice-mismatched InGaAs nanowires formed on GaAs(111)B by selective-area MOVPE
  Masatoshi Yoshimura; Katsuhiro Tomioka; Kenji Hiruma; Shinjiroh Hara; Junichi Motohisa; Takashi Fukui
  Journal of Crystal Growth, 315, 1, 148, 151, Sep. 2010, [Peer-reviewed]
  English, Scientific journal
• Noteworthy technology and materials: Development of new structural light emission element using silicon substrate
  冨岡克広; 福井孝志
  月刊ディスプレイ, 7, 7, 39, 46, テクノタイムズ社, Jul. 2010, [Invited]
  Japanese, Scientific journal
• AlGaAs/GaAs core-multishell nanowire based light-emitting diode on Si substrate
  K. Tomioka; J. Motohisa; S. Hara; K. Hiruma; T. Fukui
  Nano Letters, 10, 5, 1639, 1644, Apr. 2010, [Peer-reviewed]
  English, Scientific journal
• Structural Transition in Indium Phosphide Nanowires
  Yusuke Kitauchi; Yasunori Kobayashi; Katsuhiro Tomioka; Shinjiro Hara; Kenji Hiruma; Takashi Fukui; Junichi Motohis
  Nano Letters, 10, 5, 1699, 1703, Apr. 2010, [Peer-reviewed]
  English, Scientific journal
• Growth and Characterization of InGaAs Nanowires Formed on GaAs(111)B by Selective-Area Metal Organic Vapor Phase Epitaxy
  Masatoshi Yoshimura; Katsuhiro Tomioka; Kenji Hiruma; Shinjiro Hara; Junichi Motohisa; Takashi Fukui
  Japanese Journal of Applied Physics, 49, 4, 04DH08-1, 04DH08-4, The Japan Society of Applied Physics, Apr. 2010, [Peer-reviewed]
  English, Scientific journal, We fabricated InGaAs nanowires (NWs) in SiO2 mask openings on a GaAs(111)B substrate at growth temperatures of 600–700 °C using catalyst-free selective-area metal organic vapor phase epitaxy. At a growth temperature of 600 °C, particle-like depositions occurred, but they decreased in number and density when the growth temperature was increased to 650 °C and disappeared above 675 °C. The heights and growth rates of the NWs increased when the growth temperature was increased and the mask opening diameter was decreased from 300 to 50 nm. Photoluminescence (PL) spectra measured for the NWs indicated a blue shift in the peak from 0.95 to 1.3 eV as the growth temperature was increased from 600 to 700 °C, indicating an increase in the Ga composition from 62 to 88% in the InGaAs NWs.
• Vertical Surrounding Gate Transistors Using Single InAs Nanowires Grown on Si Substrates
  T. Tanaka; K.Tomioka; S. Hara; J. Motohisa; E. Sano; T. Fukui
  Applied Physics Express, 3, 2, 025003-1, 025003-3, The Japan Society of Applied Physics, Jan. 2010, [Peer-reviewed]
  English, Scientific journal, We report on the fabrication and characterization of vertical InAs nanowire channel field effect transistors (FETs) with high-$k$/metal gate-all-around structures. Single InAs nanowires were grown on Si substrates by the selective-area metalorganic vapor phase epitaxy method. The resultant devices exhibited n-channel FET characteristics with a threshold voltage of around $-0.1$ V. The best device exhibited maximum drain current ($I_{\text{DS,max } }/w_{\text{G } }$), maximum transconductance ($g_{\text{m,max } }/w_{\text{G } }$), on--off ratio ($I_{\text{ON/OFF } }$), subthreshold slope ($\mathit{SS}$) of 83 μA/μm, 83 μS/μm, $10^{4}$, and 320 mV/decade, respectively, for a nanowire diameter of 100 nm.
• Selective-area MOVPE growth and optical properties of single InAsP quantum dots embedded in InP NWs
  Yasunori Kobayashi; Junichi Motohisa; Katsuhiro Tomioka; Shinjiro Hara; Kenji Hiruma; Takashi Fukui
  2010 22ND INTERNATIONAL CONFERENCE ON INDIUM PHOSPHIDE AND RELATED MATERIALS (IPRM), 2010, [Peer-reviewed]
  English, International conference proceedings
• Optical properties and application of MOVPE-grown III-V nanowires
  J. Motohisa; K. S. K. Varadwaj; K. Tomioka; T. Fukui
  2010 15TH OPTOELECTRONICS AND COMMUNICATIONS CONFERENCE (OECC), 214, +, 2010, [Peer-reviewed]
  English, International conference proceedings
• Fabrication of III-V semiconductor core-shell nanowires by SA-MOVPE and their device applications
  T. Fukui; K. Tomioka; S. Hara; K. Hiruma; J. Motohisa
  PROCEEDINGS OF 2010 CONFERENCE ON OPTOELECTRONIC AND MICROELECTRONIC MATERIALS AND DEVICES (COMMAND 2010), 209, 210, 2010, [Peer-reviewed]
  English, International conference proceedings
• FABRICATION OF III-V SEMICONDCTOR NANOWIRES BY SA-MOVPE AND THEIR APPLICATIONS TO PHOTONIC AND PHOTOVOLTAIC DEVICES
  T. Fukui; K. Tomioka; S. Hara; K. Hiruma; J. Motohisa
  2010 22ND INTERNATIONAL CONFERENCE ON INDIUM PHOSPHIDE AND RELATED MATERIALS (IPRM), 2010, [Peer-reviewed]
  English, International conference proceedings
• Knowledge exploratory project for nanodevice design and manufacturing
  Masaharu Yoshioka; Katsuhiro Tomioka; Shinjiroh Hara; Takashi Fukui
  iiWAS2010 - 12th International Conference on Information Integration and Web-Based Applications and Services, 871, 874, ACM, 2010, [Peer-reviewed]
  English, International conference proceedings
• Growth of Core-Shell InP Nanowires for Photovoltaic Application by Selective-Area Metal Organic Vapor Phase Epitaxy
  H. Goto; K. Nosaki; K. Tomioka; S. Hara; K. Hiruma; J. Motohisa; T. Fukui
  Applied Physics Express, 2, 3, 035004-1, 035004-3, The Japan Society of Applied Physics, Feb. 2009, [Peer-reviewed]
  English, Scientific journal, We report on the formation of core--shell pn junction InP nanowires using a catalyst-free selective-area metalorganic vapor-phase epitaxy (SA-MOVPE) method. A periodically aligned dense core--shell InP nanowire array was fabricated and used in photovoltaic device applications. The device exhibited open-circuit voltage ($V_{\text{OC } }$), short-circuit current ($I_{\text{SC } }$) and fill factor (FF) levels of 0.43 V, 13.72 mA/cm2 and 0.57, respectively, which indicated a solar power conversion efficiency of 3.37% under AM1.5G illumination. This study demonstrates that high quality core--shell structure nanowire fabrication is possible by SA-MOVPE and that the nanowire arrays can be used in integrated nanowire photovoltaic devices.
• Selective-area growth of vertically aligned GaAs and GaAs/AlGaAs core-shell nanowires on Si(111) substrate
  K. Tomioka; Y. Kobayashi; J. Motohisa; S. Hara; T. Fukui
  Nanotechnology, 20, 145302, 2009
• Exciton coherence in clean single InP/InAsP/InP nanowire quantum dots emitting in infra-red measured by Fourier spectroscopy
  H. Sasakura; H. Kumano; I. Suemune; J. Motohisa; Y. Kobayashi; M. van Kouwen; K. Tomioka; T. Fukui; N. Akopian; V. Zwiller
  16TH INTERNATIONAL CONFERENCE ON ELECTRON DYNAMICS IN SEMICONDUCTORS, OPTOELECTRONICS AND NANOSTRUCTURES (EDISON 16), 193, 01232, 2009, [Peer-reviewed]
  English, International conference proceedings
• Fabrication and excitation-power-density-dependent micro-photoluminescence of hexagonal nanopillars with a single InGaAs/GaAs quantum well
  L. Yang; J. Motohisa; K. Tomioka; J. Takeda; T. Fukui; M-M Geng; L-X. Jia; L. Zhang; Y-L. Liu
  Nanotechnology, 19, 275304-1, 275304-7, May 2008, [Peer-reviewed]
  English, Scientific journal
• Catalyst-free growth and FET application of (InGa) as nanowires
  J. Noborisaka; T. Sato; J. Motohisa; K. Tomioka; S. Hara; T. Fukui
  Device Research Conference - Conference Digest, DRC, 177, 178, 2008, [Peer-reviewed]
  English, International conference proceedings
• Formation of III-V Compound Semiconductor Nanowires by using Selective-area MOVPE
  Katsuhiro TOMIOKA; Takuya SATO; Shinjiroh HARA; Junichi MOTOHISA; Takashi FUKUI
  Hyomen Kagaku, 29, 12, 726, 730, Surface Science Society Japan, 2008
  Japanese, Scientific journal, We report on the growth of III-V compound semiconductor nanowires by selective-area MOVPE. Position-controlled growth of GaAs nanowire, and InP/InAs/InP core-multi shell nanowires are reviewed. The nanowires are oriented to <111>B or <111>A directions and they have hexagonal cross-section surrounded with {1-10} vertical side facets and (111)B or A top surface. Also, we can control the growth direction to axial or radial by changing the growth parameters. InP/InAs/InP core-multi shell nanowires whose well thickness is of several monolayers are fabricated by using this method. We also review on the growth of vertical GaAs nanowires on Si substrate and fabrication of InGaAs nanowire-FETs.
• Control of InAs nanowire growth directions on Si
  TOMIOKA K.
  Nano Lett., 8, 10, 3475, 3480, 2008
• III-V族化合物半導体ナノワイヤにおける閃亜鉛鉱構造とウルツ鉱構造の構造相転移
  比留間 健之; 池尻 圭太郎; 吉田 浩惇; 冨岡 克広; 本久 順一; 原 真二郎; 福井 孝志
  日本結晶成長学会誌, 34, 4, 36, 44, Jan. 2008, [Peer-reviewed]
  Japanese, Scientific journal
• Electrical Characterizations of InGaAs Nanowire-Top-Gate Field-Effect Transistors by Selective-Area Metal Organic Vapor Phase Epitaxy
  J. Noborisaka; T. Sato; J. Motohisa; S. Hara; K. Tomioka; T. Fukui
  Japanese Journal of Applied Physics, 46, 11, 7562, 7568, INSTITUTE OF PURE AND APPLIED PHYSICS, Nov. 2007, [Peer-reviewed]
  English, Scientific journal, Single InGaAs nanowire-top-gate metal–semiconductor field-effect transistors (MESFETs) were fabricated and characterized. Silicon-doped n-InGaAs nanowires (with a typical diameter of 100 nm) were grown by catalyst-free selective-area metal–organic vapor-phase epitaxy (SA-MOVPE). The FETs of single nanowires on SiO2-coated Si substrates were fabricated by defining metal contacts at both ends of the nanowires and the metal top gate between contacts. According to the measurements of drain current–voltage and gate transfer characteristics, the top-gate MESFETs exhibited significant enhancements in device performance characteristics compared with FETs under back-gate operation; that is, a peak transconductance of 33 mS/mm and a current on–off ratio of $10^{3}$ were obtained. A possibility for further improvements in FET characteristics was also considered.
• Growth of highly uniform InAs nanowire arrays by selective-area MOVPE
  K. Tomioka; P. Mohan; J. Noborisaka; S. Hara; J. Motohisa; T. Fukui
  Journal of Crystal Growth, 298, 644, 2007
• Crystallographic Structure of InAs Nanowires Studied by Transmission Electron Microscopy
  Tomioka Katsuhiro; Motohisa Junichi; Hara Shinjiroh; Fukui Takashi
  Jpn J Appl Phys, 46, 45, L1102, L1104, INSTITUTE OF PURE AND APPLIED PHYSICS, 2007
  English, Crystallographic structure of InAs nanowires, which were grown by selective-area metalorganic vapor phase epitaxy on (111)B-oriented substrates, was investigated by transmission electron microscopy (TEM). The TEM images showed that the nanowires had many stacking faults along the growth direction. Statistical analysis of the atomic-layer stacking showed that InAs nanowires contained both zincblende and wurtzite crystal phases, whose transition took place in every one to three monolayers. This specific crystal phase transition resulted in peculiar electron diffraction patterns. The stacking of the atomic layers had no distinct correlation with the diameter of the nanowires.
• Selective-area growth of hexagonal nanopillars with single InGaAs/GaAs quantum, wells on GaAs(111)B substrate and their temperature-dependent photoluminescence
  L. Yang; J. Motohisa; J. Takeda; S. Hara; K. Tomioka; T. Fukui
  Nanotechnology, 18, 105302-1, 105302-5, Jan. 2007, [Peer-reviewed]
  English, Scientific journal
• Size-dependent photoluminescence of hexagonal nanopillars with single InGaAs/GaAs quantum wells fabricated by selective-area metal organic vapor phase epitaxy
  L. Yang; J. Motohisa; J. Takeda; K. Tomioka; T. Fukui
  Applied Physics Letters, 89, 203110-1, 203110-3, Nov. 2006, [Peer-reviewed]
  English, Scientific journal
• Ultraviolet emission from porous silicon photosynyhesized in aqueous alkali fluoride solutions
  K. Uchida; K. Tomioka; S. Adachi
  Journal of Applied Physics, 100, 3, 014301-1, 014301-5, American Institute of Physics, Jul. 2006, [Peer-reviewed]
  English, Scientific journal, Stable ultraviolet (UV) photoluminescence (PL) has been observed at room temperature in poroussilicon (PSi) fabricated by photoetching in aqueous alkali fluoride solutions. The aqueous solutionsused are 1 M NaF and 1 M KF.They give an alkaline reaction caused by partial hydrolysis. The PLpeaks at ～3.3 eV have a full width at half maximum of ～0.1 eV, which is much smaller than thosereported previously (?0.5 eV). Spectral analyses suggest that both quantum confinement andsurface passivation effects enable the observation of UV emission in NaF- and KF-prepared PSisamples.
• Selective-area growth of the hexagonal nano-pillars with single InGaAs/GaAs quantum well and their temperature-dependence photoluminescence
  L. Yang; J. Motohisa; J. Takeda; K. Tomioka; T. Fukui
  2006 6th IEEE Conference on Nanotechnology, IEEE-NANO 2006, 2, 706, 709, Institute of Electrical and Electronics Engineers Inc., 2006
  English, International conference proceedings
• Strong and stable ultraviolet emission from porous silicon prepared by photoetching in KF solution
  TOMIOKA K.
  Applied Physics Letters, 87, 25, 251920-1, 251920-3, American Institute of Physics, Dec. 2005, [Peer-reviewed]
  English, Scientific journal, A new method of fabricating porous silicon emitting in the ultraviolet (UV) spectral region ispresented. This method uses photoetching in an aqueous salt (KF) solution. Strong UVphotoluminescence is observed at ～3.3 eV with a full width at a half maximum of ～0.1 eV, whichis much narrower than those reported previously. Fourier transform infrared spectroscopy suggeststhat the surface oxide produced during photoetching plays an important role in the UV emission ofthe KF-prepared PSi.
• Structural and photoluminescence properties of porous GaP formed by electrochemical etching
  Katsuhiro Tomioka; Sadao Adachi
  Journal of Applied Physics, 98, 7, 073551-1, 073551-7, American Institute of Physics, Oct. 2005, [Peer-reviewed]
  English, Scientific journal, The structural and optical properties of porous GaP have been studied by scanning electronmicroscopy, spectroscopic ellipsometry, and photoluminescence (PL) spectroscopy. Porous GaPlayers were fabricated by anodic etching in HF:H2O:C2H5OH=1:1:2 electrolyte on n-type (100)and (111)A substrates. The morphology of the porous GaP layer is found to depend strongly on thesurface orientation. Apart from the red emission band at ～1.7 eV, a supra-band-gap (EgX) emissionhas been clearly observed on the porous GaP (111)A sample. The anodic porous layer on the (100)substrate, on the other hand, has shown only the red emission at 300 K and both red and greendonor-acceptor pair emissions at low temperatures. The correlation between the PL properties andthe porous morphology is discussed. An optical transition model is also proposed for the explanationof the PL emission properties of the porous GaP samples.
• Visible light emission from porous silicon prepared by photoetching in alkaline solution
  Sadao Adachi; Katsuhiro Tomioka
  Electrochemical Solid-State Letters, 8, 10, G251, G253, Aug. 2005, [Peer-reviewed]
  English, Scientific journal
• Spectroscopic characterization of GaP surfaces treated in HCl solution
  Katsuhiro Tomioka; Sadao Adachi
  Journal of the Electrochemical Society, 152, 3, G173, G178, Jan. 2005, [Peer-reviewed]
  English, Scientific journal

• Integration of III-V Nanowires on Si and Surrounding-Gate FET
  TOMIOKA Katsuhiro; FUKUI Takashi, 電気学会研究会資料. EDD, 電子デバイス研究会, 2012, 30, 45, 50, 07 Mar. 2012
  Japanese
• 1Pb-6 Acoustic Modes of GaAs Nanopillars Studied with Ultrashort Optical Pulses(Poster Session)
  Sakuma Hirotaka; Tomoda Motonobu; Matsuda Osamu; Fukui Takashi; Tomioka Katsuhiro; Veres Istvan A.; Wright Oliver B., Proceedings of Symposium on Ultrasonic Electronics, 31, 153, 154, 06 Dec. 2010
  Steering committee of symposium on ultrasonic electronics, English
• CT-2-4 InAs-BASED NANOWIRE TRANSISTORS
  Motohisa Junichi; Tanaka Tomotaka; Tomioka Katsuhiro; Fukui Takashi, Proceedings of the IEICE General Conference, 2010, 2, "SS, 45", 02 Mar. 2010
  The Institute of Electronics, Information and Communication Engineers, Japanese
• 2P1-4 Vibrations of nanostructures probed by ultrashort optical pulses(Poster Session)
  Sakuma Hirotaka; Tomoda Motonobu; Matsuda Osamu; Fukui Takashi; Tomioka Katsuhiro; Wright Oliver B., Proceedings of Symposium on Ultrasonic Electronics, 30, 209, 210, 18 Nov. 2009
  Steering committee of symposium on ultrasonic electronics, English
• 1J2a-3 Vibrational modes of semiconductor nanopillars studied by picosecond ultrasonics(Measurement techniques)
  Sakuma Hirotaka; Tomoda Motonobu; Matsuda Osamu; Fukui Takashi; Tomioka Katsuhiro; Wright Oliver B., Proceedings of Symposium on Ultrasonic Electronics, 29, 19, 20, 11 Nov. 2008
  We investigate the vibrational modes of GaAs nanopillars of hexagonal cross section on a GaAs substrate using an ultrafast optical technique. The motions of the pillars after excitation with visible light pulses are detected using a time-delayed infrared light pulses. Thickness modes of the pillars are detected in the 10-30 GHz range., Steering committee of symposium on ultrasonic electronics, Japanese
• Formation of III-V Compound Semiconductor Nanowires and a Crystal Structure Change between Zincblende and Wurtzite
  HIRUMA Kenji; IKEJIRI Keitaro; YOSHIDA Hiroatsu; TOMIOKA Katsuhiro; MOTOHISA Junichi; HARA Shinjiroh; FUKUI Takashi, Journal of the Japanese Association of Crystal Growth, 34, 4, 224, 232, 30 Nov. 2007
  GaAs and InAs nanowires were selectively grown by using metal-organic vapor-phase epitaxy. The nanowires were as thin as several tens to several hundreds nanometers and as long as several micronmeters. Scanning electron microscope observations showed that the growth direction of nanowires was parallel to the <111> B crystallographic orientation. It was found by a transmission electron microscopy analysis that the crystal structure of the GaAs nanowire was zincblende with rotational twins around the <111> axis. For the GaAs nanowires, the density of twins along the <111> direction increased as the nanowire diameter decreased. The growth mechanism was understood based upon a model that the GaAs nanowire was composed of stacked thin-layers with interfaces containing rotational twins., The Japanese Association for Crystal Growth (JACG), Japanese

• 半導体・磁性体・電池の固/固界面制御と接合・積層技術
  化合物半導体ナノワイヤ異種集積技術, 第2章第6節
  S&T出版, Jun. 2024, 9784911146040, 244 p, Japanese, [Contributor]
• Emerging Devices for Low-Power and High-Performance Nanosystems: Physics, Novel Functions, and Data Processing
  Tomioka Katsuhiro, Chapter 2 - Several Challenges in Steep-Slope Tunnel Field-Effect Transistors
  Pan Stanford, Aug. 2018, 9814800112, 450, Scholarly book, [Contributor]
• Novel Compound Semiconductor Nanowires – Materials, Devices, and Applications
  Tomioka Katsuhiro, Chapter 14 – III-V Nanowires: Transistor and photovoltaic applications
  Pan Stanford Publishing, Nov. 2017, 9814745766, 53, p. 464 – 516, [Contributor]
• Handbook of Crystal Growth, Second Edition edited by T. Nishinaga, P. Rudolph, and T. Kuech
  Katsuhiro Tomioka; Takashi Fukui, Chapter 4 in Volume: 2A - Growth of Semiconductor Nanocrystals
  Elsevier, Dec. 2014, 9780444563699, [Contributor]
• ナノワイヤ最新技術の基礎と応用展開
  冨岡克広, 第III編第3章 - ナノワイヤのトランジスタ応用
  株式会社シーエムシー出版, Mar. 2013, 9784781307602, 241, 208-223, Japanese, [Contributor]
• Semiconductor Nanowire and Their Optical Applications
  Katsuhiro Tomioka; Takashi Fukui, Chapter 3: III-V Semiconductor Nanowires on Si by Selective-Area Metal-Organic Vapor Phase Epitaxy.
  Springer, Jan. 2012, 3642224792, English, Scholarly book, [Contributor]
• Advances in III-V Semiconductor Nanowires and Nanodevices, edited by J. Li, D. Wang, and R. R. LaPierre
  Junichi Motohisa; Katsuhiro Tomioka; Bin Hua; Kumar S; K. Varadwaj; Shinjiroh Hara; Kenji Hiruma; Takashi Fukui, III-V Semiconductor Nanowire Light Emitting Diodes and Lasers
  Bentham Science Publisher, Nov. 2011, [Contributor]

• Selective-area growth of InGaAs/GaAs super-lattice nanowires and vertical gate-all-around resonant tunnel transistor
  Katsuhiro Tomioka
  International Symposium on Semiconductor Optoelectronics and Nanotechnology (ISSON), Canberra, Australia, 09 Dec. 2025
  [Invited]
• (Invited) Integration of vertical III-V nanowires on Si and their transistor applications
  Katsuhiro Tomioka
  Bilateral Workshop on Low-dimensional Semiconductors, Taipei, Taiwan, 05 Dec. 2024
  [Invited]
• (Invited) Heterogeneous Integration of Vertical III-V Nanowires on Si and Vertical Transistor Applications
  Katsuhiro Tomioka
  Australian Institute of Physics Congress / Conference on Optoelectronic and Microelectronic Materials and Devices (COMMAD) 2024, Melbourne, Australia, 02 Dec. 2024
  [Invited]
• (Invited) Integration of Vertical III-V Nanowire Transistors on Si for Low-power LSI Cube
  Katsuhiro Tomioka
  International Workshop on Semiconductor Nanotechnology and Bio-medical Science, Sapporo, Japan, 25 Jun. 2024
  [Invited]
• (Invited) Vertical III-V Nanowire Transistors and Prospects
  Katsuhiro Tomioka
  17th D2T Symposium, 15 Sep. 2022, English, Invited oral presentation
  15 Sep. 2022, [Invited]
• (Invited) Integration of III-V Nanowires on Si and their Device Applications
  Katsuhiro Tomioka; Junichi Motohisa
  14th International Symposium on Advanced Plasma Science and its Applications for Nitrides and Nanomaterials/15th International Conference on Plasma-Nano Technology & Science (ISPlasma2022/IC-PLANTS2022), 09 Mar. 2022, English, Invited oral presentation
  06 Mar. 2022, [Invited]
• (Invited) Integration of III-V Nanowire on Si and Their Device Application
  Katsuhiro Tomioka; Hironori Gamo; Junichi Motohisa
  International Union of Materials Research Societies - International Conference in Asia 2021 (IUMRS-ICA 2021), Invited oral presentation
  03 Oct. 2021 - 08 Oct. 2021, On/Offline hybrid event, Jeju, Korea, [Invited]
• (Invited) Integration of III-V nanowire LEDs on Si
  Katsuhiro Tomioka; Junichi Motohisa
  The 20th International Meeting on Information Display (IMID 2020), Invited oral presentation
  25 Aug. 2020 - 28 Aug. 2020, Online conference, Korea, [Invited]
• (Invited) InP-based Nanowires Towards On-demand Single Photon Emitters
  Junichi Motohisa; Katsuhiro Tomioka
  XXth International Workshop on Physics of Semiconductor Devices (IWPSD 2019), Invited oral presentation
  17 Dec. 2019 - 19 Dec. 2019, Kolkata, India, [Invited]
• “(Invited) Vertical Tunnel FET Technologies Using III-V/Si Heterojunction
  K. Tomioka; H. Gamo; J. Motohisa
  236th ECS meeting, 15 Oct. 2019, English, Invited oral presentation
  [Invited], [International presentation]
• Selective-Area Epitaxy of III-V Nanowires on Si and Their Switching Applications
  K. Tomioka; J. Motohisa
  7th International Workshop on Epitaxial Growth and Fundamental Properties of Semiconductor Nanostructures (Semicon Nano 2019), 27 Sep. 2019, English, Invited oral presentation
  [Invited], [International presentation]
• Integration of III-V nanowires on Si and their transistor applications (Plenary)
  Katsuhiro Tomioka
  22nd International Conference on Advanced Materials, 10 Dec. 2018, English, Keynote oral presentation
  [Invited], [International presentation]
• Transistor applications using vertical III-V nanowires on Si platform
  K. Tomioka; T. Fukui
  232nd ECS meeting, 01 Oct. 2017, English, Invited oral presentation
  [Invited], [International presentation]
• MOVPE選択成長法によるナノワイヤ成長とデバイス応用
  冨岡 克広; 本久 順一
  第78回応用物理学秋季学術講演会, 08 Sep. 2017, Japanese, Invited oral presentation
  [Invited], [Domestic Conference]
• Vertical III-V nanowires on Si and transistor applications
  K. Tomioka; J. Motohisa; T. Fukui
  The 15th International Conference on Advanced Materials (IUMRS-ICAM 2017), 01 Aug. 2017, English, Invited oral presentation
  [Invited], [International presentation]
• 半導体ナノワイヤ選択成長と電子デバイス応用
  第9回ナノ構造エピタキシャル成長講演会, 14 Jul. 2017, Japanese, Invited oral presentation
  [Invited], [Domestic Conference]
• Phase transition from Zinc Blende to Wurtzite and green-yellow emission of AlInP grown by crystal structure transfer method (Invited)
  Takashi Fukui; Yoshihiro Hiraya; Fumiya Ishizaka; Katsuhiro Tomioka
  13th Sweden - Japan QNANO Workshop, 23 Mar. 2017, English, Invited oral presentation
  [Invited], [International presentation]
• Selective area growth of III-V nanowires on Si and their transistor applications
  K. Tomioka
  2016 HU-SNU Joint Workshop, 25 Nov. 2016, English, Invited oral presentation
  [Invited]
• Recent progress in vertical Si/III-V tunnel FETs: from fundamentals to current boosting technology
  K. Tomioka; J. Motohisa; T. Fukui
  PRiME 2016, 02 Oct. 2016, English, Invited oral presentation
  [Invited], [International presentation]
• Advances in Steep-Slope Tunnel FETs
  Katsuhiro Tomioka; Junichi Motohisa; Takashi Fukui
  ESSDERC 2016, 15 Sep. 2016, English, Invited oral presentation
  [Invited], [International presentation]
• Selective-area growth of III-V nanowires on Si and transistor applications
  Katsuhiro Tomioka; Junichi Motohisa; Takashi Fukui
  The 8th International Conference on Low Dimensional Structures and Devices (LDSD 2016), 30 Aug. 2016, English, Invited oral presentation
  [Invited], [International presentation]
• Heterogeneous Integration of InGaAs-Related Nanowires on Si and Their Device Applications
  K. Tomioka; F. Ishizaka; J. Motohisa; T. Fukui
  18th International Conference on Metal-Organic Vapor Phase Epitaxy (ICMOVPE-XVIII), San Diego, USA, July 10-15 (2016), Jul. 2016, English, Invited oral presentation
  [Invited], [International presentation]
• Vertical transistors using III-V nanowires on Si
  Tomioka Katsuhiro
  2015 CNU-HU Joint Workshop, Daejeon, Korea, Nov. 20th (2015)., Nov. 2015, English, Invited oral presentation
  [Invited], [International presentation]
• Recent progress in vertical TFET using III-V/Si heterojunction
  K. Tomioka; J. Motohisa; T. Fukui
  Steep Transistors Workshop, Notre Dame, USA, Oct. 5-6 (2015)., Oct. 2015, English, Invited oral presentation
  [Invited], [International presentation]
• Vertical Tunnel FETs Using III-V Nanowire/Si Heterojunctions
  K. Tomioka; J. Motohisa; T. Fuku
  228th ECS Meeting, phoenix, Arizona, USA, Oct. 2015, English, Invited oral presentation
  [Invited], [International presentation]
• Vertical III-V nanowire transistors for future low-power switches
  K. Tomioka; T. Fukui
  12th Sweden - Japan QNANO Workshop, Hindas, Sweden, Sep. 24-25 (2015)., Sep. 2015, English, Invited oral presentation
  [Invited], [International presentation]
• Heterogeneous integration of vertical III-V nanowires on Si and Ge and their applications
  K.Tomioka; J. Motohisa; T. Fukui
  The 20th American Conference on Crystal Growth and Epitaxy and The 17th Biennial Workshop on Organometallic Vapor Phase Epitaxy (ACCGE-20/OMVPE-17), Big Sky, Montana, USA, 2-7 Aug. (2015)., Aug. 2015, English, Invited oral presentation
  [Invited], [International presentation]
• Vertically Aligned Semiconductor Nanowire Array and Their Applications (Invited)
  T. Fukui; F. Ishizaka; K. Tomioka
  Compound Semiconductor Week 2015 (CSW2015), Santa Barbara, USA, June 28 - July 2 (2015)., Jun. 2015, English, Invited oral presentation
  [Invited], [International presentation]
• III-V nanowire channel on Si: From high-performance Vertical FET to steep-slope device
  K. Tomioka; J. Motohisa; T. Fukui
  2015 International Symposium on VLSI Technology, Systems and Applications (2015 VLSI-TSA), Hsinchu, Taiwan, April 27-29 (2015), Apr. 2015, English, Invited oral presentation
  [Invited], [International presentation]
• シリコン基板上のInAsナノワイヤ縦型サラウンディングゲートFETの作製
  第70回応用物理学学術講演会, 2009
• GaAs(111)B上にMOVPE選択成長されたInGaAsナノワイヤの成長温度依存性評価
  第70回応用物理学学術講演会, 2009
• AlGaAs/GaAsコア・マルチシェルナノワイヤ発光ダイオードの作製とSi基板上への集積化
  第70回応用物理学学術講演会, 2009, Poster presentation
• シリコン基板上のGaAsナノワイヤ成長：コヒーレント成長の実現
  第70回応用物理学学術講演会, 2009
• MOVPE選択成長法によるSi(111)基板上のInAsナノワイヤ成長
  第55回応用物理学関係連合講演会, 2008
• MOVPE選択成長したInAsナノワイヤの縦型二端子測定
  第69回応用物理学学術講演会, 2008
• MOVPE選択成長法によるSi基板上のGaAs/AlGaAsコア・シェルナノワイヤの作製
  第69回応用物理学学術講演会, 2008, Poster presentation
• MOVPE選択成長法により作製したInAsナノワイヤのTEM観察
  第54回応用物理学関連連合講演会, 2007
• MOVPE選択成長法によるSi(111)基板上のIII-V化合物半導体ナノワイヤの作製
  第68回応用物理学学術講演会, 2007
• (Invited) Selective-Area Growth of Vertical III-V Nanowires on Si and Transistor Applications
  Katsuhiro Tomioka
  AM&ST-24, Hobart, Australia
  [Invited]

• 半導体デバイス物理学特論, 2024年, 修士課程, 情報科学院
• 半導体デバイス物理学特論, 2024年, 博士後期課程, 情報科学院
• 量子デバイス学特論, 2024年, 博士後期課程, 情報科学研究科
• 科学・技術の世界（1単位）, 2024年, 学士課程, 全学教育
• 科学・技術の世界（1単位）, 2024年, 学士課程, 全学教育
• 電子デバイス工学, 2024年, 学士課程, 工学部
• 電気電子材料工学, 2024年, 学士課程, 工学部

• JAPANESE ASSOCIATION FOR CRYSTAL GROWTH
• IEEE
• 応用物理学会

• Semiconductor Crystal Phase Heterojunction Electronics
  Grants-in-Aid for Scientific Research
  27 Jun. 2025 - 31 Mar. 2029
  冨岡 克広
  Japan Society for the Promotion of Science, Grant-in-Aid for Challenging Research (Pioneering), Hokkaido University, 25K21682
• Near to Middle Infrared Photodetector Utilizing Core-Shell Semiconductor Nanowires
  Grants-in-Aid for Scientific Research
  01 Apr. 2025 - 31 Mar. 2028
  本久 順一; 冨岡 克広
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 25K01256
• 縦型半導体ナノワイヤアレイ量子集積回路基盤技術の創成
  戦略的な研究開発の推進 戦略的創造研究推進事業 CREST
  2023 - 2028
  冨岡 克広
  III-V族化合物半導体ナノ材料の選択成長技術とヘテロ接合形成技術を発展させ、異なるキャリア・機能を1つの素子に統合する新型デバイスの実証に立脚した3次元立体集積プロセス・システム・回路技術を構築し,縦型ナノワイヤアレイ立体量子集積回路の学術基盤を確立することで、従来の集積回路技術では原理的に実現できない、消費電力・発熱を極限まで抑制した新たな省電力エレクトロニクスの基礎を築きます。
  科学技術振興機構, 北海道大学, Principal investigator
• Development on strucural phase transition semiconductors
  FOREST
  Apr. 2021 - Mar. 2027
  JST, 創発的研究支援事業, Hokkaido Univ.
• Vertical-Ge-nanowire-based spin devices
  Grants-in-Aid for Scientific Research
  28 Jun. 2024 - 31 Mar. 2026
  山田 道洋; 冨岡 克広
  Japan Society for the Promotion of Science, Grant-in-Aid for Challenging Research (Exploratory), Tokyo City University, 24K21736
• Development of nanowire hybrid integrated devices
  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
  Apr. 2022 - Mar. 2026
  冨岡 克広; 池辺 将之; 本久 順一
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, 22H00202
• III-V族化合物半導体ナノ選択成長技術の確立とナノフォトニクス応用
  国際的な科学技術共同研究などの推進 先端国際共同研究推進事業 単独公募(次世代)
  2023 - 2026
  冨岡 克広
  本研究は半導体材料結晶成長学分野における未踏領域であるシリコン上の構造相転移材料系材料のナノ選択成長技術を確立することで、将来のチップ内光配線技術や高度な小型ナノ分光測定技術などの次世代ナノフォトニクスにおける高輝度・高機能ナノ光源の基盤技術の創出を目的とする。具体的には、日本側チームはシリコン基板上の構造相転移ナノワイヤ材料のナノ選択成長技術の伝導形制御手法とナノ光源素子のデバイス開発を行い、相手側チームはシリコン基板上の構造相転移ナノ構造に関するナノ選択成長技術とともに成長材料の光学的特性・物性の評価を行う。
  科学技術振興機構, 北海道大学, Principal investigator
• Development of vertical HEMT-type devices using Si-Ge core-shell heterojunction nanowires
  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
  Apr. 2021 - Mar. 2025
  深田 直樹; J. Wipakorn; 宮崎 剛; 本久 順一; 冨岡 克広; 松村 亮
  現行の平面型金属・酸化膜・半導体電界効果型トランジスタ（MOSFET）では、微細化した回路素子からのリーク電流による発熱が大きくなるため、従来のスケール則に従った微細化だけでは素子の性能向上に限界が指摘されている。本研究では、IV族半導体Si、Ge、新規高移動度材料として注目されているGeSnから形成される特殊なコアシェルヘテロ接合により高電子移動度型トランジスタ（HEMT）構造を１次元ナノワイヤ内部に形成することで、次世代トランジスタの微細化限界・低消費電力化の課題を解決し、ナノ構造でも不純物散乱のない高移動度デバイスを実現する。
  初年度はサイズ・配列制御可能で、大面積での繰り返しパターン形成が容易で時間短縮できるナノインプリント法と反応性イオンエッチング（RIE）法を適用し、i(intrinsic)-Ge/p-Si、逆構造であるp-Si/i-Geおよびp-Si/i-Ge1-xSnxコアシェルナノワイヤ中のコア領域のp-Siおよびi-Geナノワイヤアレイの形成を行った。RIEの条件をSiとGeで最適化することで、直径150nmのi-Geおよびp-Siナノワイヤアレイのサイズ・配列制御に成功した。RIEではナノワイヤ表面にダメージが導入される。そこで、表面ダメージ層を低温オゾン酸化とエッチングで除去し、ナノワイヤ径を高速チャネルのサイズとして利用できる50nmまで縮小化することに成功した。ナノワイヤFET形成のためのプロセスおよび大規模第一原理計算によるコアシェルナノワイヤモデルの構築を行った。
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), National Institute for Materials Science, 21H04642
• Generation of Vector Beams using Semiconductor Nanowires
  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
  Apr. 2020 - Mar. 2023
  本久 順一; 冨岡 克広
  令和2年度は、ナノワイヤを利用したベクトル光波を発生する素子構造として提案しているもののうち、WGM型の発光特性の評価を行うとともに、そのナノワイヤからのベクトル光波の発生を確認した。具体的には、有機金属気相選択成長法により作製したGaAs/InGaAs/GaAs コアマルチシェル構造のナノワイヤに対し、まず連続光励起下の顕微PL測定により、Q値が200程度の共振モードが複数のナノワイヤで観測されることを確認した。そして、パルス光励起による評価を行ったところ、連続光励起ではブロードな発光しか観測されなかった波長において、励起光強度に対し非線形的に増大する発光ピークを複數のナノワイヤにおいて観測した。これはナノワイヤがレーザ発振していることを強く示している。そして、連続光およびパルス光励起のそれぞれの条件で、発光のピーク強度の偏光依存性を評価したところ、λ/2波長板の回転角に対し90度周期で強度が振動的に変化する一方で、λ/4波長板に対してはその回転角にはほとんど依存しない発光ピークが存在することが明らかとなった。これはナノワイヤからの発光が単純な直線偏光もしくは円偏光とはなっていないことを示している。さらに、パルス光励起の条件下で非常に強度の強い単一ピークが観測されているナノワイヤについて、その発光像を観測したところ、発光像の強度分布が、λ/2波長板の回転角に応じて周期的・空間的に変化することが明らかとなった。この結果は、ナノワイヤからの発光スポットの偏光分布が空間的に一様でなく、そしてまた軸対称となっていることを示しており、以上よりベクトル光波の発生が確認された。同時に発光像のストークス解析を行ったところ、得られたナノワイヤからのベクトル光波は低次のベクトル光波となっていることを示唆する実験結果が得られた。
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 20H02176
• Demonstration of ultrafast resonant tunneling transistor
  Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Research (Exploratory)
  Jun. 2019 - Mar. 2022
  Tomioka Katsuhiro
  In this research, we developed a formation of superlattice NWs by selective-are growth technique and demonstrated vertical diode and vertical gate all-around resonant tunneling transistor (VGAA-RTFET) device using the superlattice nanowires for the first time. The demonstrated VGAA-RTFET device has realized high-speed switching properties with high tunneling current and steep subthreshold slope (SS), and material and device technologies that simultaneously solve the TFET problem of high switching current and steep SS have been realized. This has pioneered a new methodology for low-power switching devices and high-frequency devices.
  Japan Society for the Promotion of Science, Grant-in-Aid for Challenging Research (Exploratory), Hokkaido University, 19K21951
• Inverstigation on vertical tunnel FET using Si/III-V heterojunction and their three-dimensional integrated circuit applications
  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
  Apr. 2019 - Mar. 2022
  Tomioka Katsuhiro
  In this research, we developed and explored heterogeneous integration of III-V nanowires heterogeneous for high-speed, low-power, and high-efficiency three-dimensional (3D) circuits application. a nanowire 3D-architecture revolutionized the existing planar integration paradigm, and created a new trend in next-generation electronics. We have created an ultra-efficient tunnel transistors driven by nanowatts based on a new Si/III-V nanowire junction and tunneling transport mechanism. These results would provided new design guidelines for three-dimensional circuit structures based on nanowire TFETs.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 19H02184
• 化合物半導体ナノワイヤによる立体縦型トランジスタ高速CMOS技術の確立
  平成３０年度助成
  Apr. 2018 - Mar. 2021
  冨岡 克広
  一般財団法人 テレコム先端技術研究支援センター, Principal investigator, Competitive research funding
• 新しい半導体接合を用いた低電圧スイッチ素子の高性能化
  2017年度研究助成（基礎研究）
  Apr. 2018 - Mar. 2020
  冨岡 克広
  公益財団法人 東電記念財団, Principal investigator, Competitive research funding
• Study on Light-Emittind Devices on Si Substrates based on Semiconductor Nanowires
  Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
  Apr. 2017 - Mar. 2020
  Motohisa Junichi
  We attempted the growth of InGaAs nanowires (NWs) on Si substrates by selective-area metalorganic vapor-phase epitaxy. By controlling the supply ratio of source materials of group III atoms, emission from InGaAs NW arrays in the telecommunication bands were successfully confirmed by the low-temperature photoluminescence measurement. InGaAs NW arrays with a vertical pn junction are also fabricated and photocurrent spectroscopy reveals that fabricated NW array exhibited optical bandgap in the telecommunication bands. Emission mechanism of InP-based light-emitting diode (LED) was investigated and radiative tunneling was the dominant emission mechanism in the NW-LEDs. Control of the emission wavelength and size of InAsP quantum dots embedded in InP NWs were attempted and emission from the telecommunication band was demonstrated. NW-LEDs utilizing InAsP/InP heterostructure NWs were also fabricated and confirmed the light emission in the near-infrared regions originating from InAsP layer.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (B), Hokkaido University, 17H03223
• 高品質狭ギャップ化合物半導体ナノワイヤ材料の創生と省エネルギー電子素子応用
  第34回(2016年度)一般研究助成（新材料）
  Apr. 2017 - Mar. 2020
  冨岡 克広
  公益財団法人 矢崎科学技術振興記念財団, Principal investigator, Competitive research funding
• IV族/III-V族ヘテロ接合の界面欠陥制御に基づく低電圧スイッチ素子の回路応用
  科学研究費助成事業（科学研究費補助金）若手研究（A)
  Apr. 2016 - Mar. 2019
  冨岡 克広
  独立行政法人日本学術振興会, Principal investigator, Competitive research funding
• 高品質狭ギャップ化合物半導体ナノワイヤ材料の創生と低電圧電子素子応用
  第1回(2018年度)一般研究助成
  Oct. 2017 - Oct. 2018
  冨岡 克広
  公益財団法人 サムコ科学技術振興財団, Principal investigator, Competitive research funding
• 半導体ナノワイヤを用いた新型光検出器 (分担)
  科学研究費助成事業 挑戦的萌芽研究
  Apr. 2016 - Mar. 2018
  本久 順一
  独立行政法人日本学術振興会, Competitive research funding
• 新しい半導体接合による低電圧スイッチ素子応用と高性能化に関する研究
  第34回（平成28年度）研究助成
  Dec. 2016 - Dec. 2017
  冨岡 克広
  公益財団法人 カシオ科学振興財団, Principal investigator, Competitive research funding
• ナノワイヤ異種集積技術に基づくGe/III-V ハイブリッド電子デバイスの創成
  第32回(2016年度)マツダ研究助成
  Nov. 2016 - Nov. 2017
  冨岡 克広
  公益財団法人 マツダ財団, Principal investigator, Competitive research funding
• ナノワイヤ異種集積技術に基づくGe/III-Vハイブリッド電子デバイスの創成
  平成28年度 研究助成（自然科学）
  Jun. 2016 - Jun. 2017
  冨岡 克広
  公益財団法人 村田学術振興財団, Principal investigator, Competitive research funding
• 化合物半導体ナノワイヤによる光デバイス応用(分担)
  科学研究費助成事業（科学研究費補助金）基盤研究（S）
  Apr. 2015 - Mar. 2016
  福井孝志
  独立行政法人日本学術振興会, Competitive research funding
• Development of novel hydrogen-generating devices and low-power switch using new semiconductor heterointerfaces
  PRESTO
  Oct. 2012 - Mar. 2016
  Tomioka Katsuhiro
  JST, Principal investigator, Competitive research funding
• Si/III-V族半導体超ヘテロ界面の機能化と低電力スイッチ素子の開発
  ＪＳＴ戦略的創造研究推進制度（個人研究型） （個人研究推進事業：さきがけ研究２１‐ＰＲＥＳＴＯ）
  2009 - 2013
  Competitive research funding
• Si/III-V族化合物半導体ナノワイヤへテロ接合界面のTEM観察評価とその応用に関する研究
  笹川研究助成
  Apr. 2009 - Mar. 2010
  冨岡 克広
  日本科学協会, Principal investigator, Competitive research funding
• 半導体ナノワイヤに形成したコア・シェル量子井戸おける光物性と微小電流注入レーザーへの応用に関する研究
  研究助成
  Apr. 2009 - Mar. 2010
  冨岡 克広
  財団法人光科学技術研究振興財団, Principal investigator, Competitive research funding
• 有機金属気相選択成長法による半導体ナノワイヤへテロ構造作製とその応用に関する研究
  特別研究員奨励費 PD
  Apr. 2008 - Mar. 2009
  冨岡 克広
  独立行政法人日本学術振興会, Principal investigator, Competitive research funding
• 有機金属気相選択成長法による半導体ナノワイヤへテロ構造作製とその応用に関する研究
  特別研究員奨励費 DC2
  Apr. 2007 - Mar. 2008
  冨岡 克広
  独立行政法人日本学術振興会, Principal investigator, Competitive research funding

• マルチモードスイッチ素子
  Patent right, 蒲生 浩憲; 冨岡 克広, 北海道大学
  特願2022-48567, 24 Mar. 2022
• Group III-V compound semiconductor nanowire, field effect transistor, and switching element
  Patent right, Katsuhiro Tomioka; Takashi Fukui
  米国特許登録 US Patent 10,403,498, Apr. 2019
  米国特許登録 US Patent 10,403,498
  Apr. 2019
• トンネル電界効果トランジスタ
  Patent right, 冨岡 克広; 福井 孝志
  特願2015-193196, 30 Sep. 2015
• トンネル電界トランジスタおよびその製造方法
  Patent right, 冨岡 克広; 福井 孝志; 田中 智隆
  中華人民共和国特許登録番号ZL201080043950.2
  07 Jan. 2015
• 半導体構造物の製造方法
  Patent right, 冨岡 克広; 福井 孝志; 本久 順一; 原 真二郎
  特許番号第5655228号
  05 Dec. 2014
• トンネル電界効果トランジスタおよびその製造方法
  Patent right, 冨岡 克広; 福井 孝志; 田中 智隆
  特許番号第5652827号
  28 Nov. 2014
• 発光素子およびその製造方法
  Patent right, 冨岡 克広; 福井 孝志
  United States Patent No.8895958
  25 Nov. 2014
• III-V族化合物半導体ナノワイヤ、電界効果トランジスタおよびスイッチ素子
  Patent right, 冨岡 克広; 福井 孝志
  台湾出願103137589, 30 Oct. 2014
• III-V族化合物半導体ナノワイヤ、電界効果トランジスタおよびスイッチ素子
  Patent right, 冨岡 克広; 福井 孝志
  PCT出願PCT/JP2014/005463, 29 Oct. 2014
• Semiconductor Device and Method for Manufacturing Semiconductor Device (半導体装置および半導体装置の製造方法)
  Patent right, Takashi Fukui; Katsuhiro Tomioka; Junichi Motohisa; Shinjiroh Hara
  United States Patent No. 8816324
  24 Aug. 2014
• トンネル電界効果トランジスタ、その製造方法およびスイッチ素子
  Patent right, 冨岡 克広; 福井 孝志
  PCT出願PCT/JP2014/004175, 12 Aug. 2014
• Tunnel Field Effect Transistor and Method for Manufacturing Same (トンネル効果トランジスタ、その製造方法およびスイッチ素子)
  Patent right, Katsuhiro Tomioka; Takashi Fukui; Tomotaka Tanaka
  United States Patent No.8698254
  30 Mar. 2014
• 半導体装置及び半導体装置の製造方法
  Patent right, 福井 孝志; 冨岡 克広; 本久 順一; 原 真二郎
  特願2008-223713, 01 Sep. 2008
  特許5464458
  31 Jan. 2014
• III-V族化合物半導体ナノワイヤ、電界効果トランジスタおよびスイッチ素子
  Patent right, 冨岡 克広; 福井 孝志
  特願2013-226675, 31 Oct. 2013
• トンネル電界効果トランジスタ、その製造方法およびスイッチ素子
  Patent right, 冨岡 克広; 福井 孝志
  台湾出願103127711, 13 Aug. 2013
• トンネル電界効果トランジスタ、その製造方法およびスイッチ素子
  Patent right, 冨岡 克広; 福井 孝志
  特願2013-168048, 13 Aug. 2013
• 発光素子およびその製造方法
  Patent right, 福井 孝志; 石坂 文哉; 冨岡 克広
  特願2013-138894, 02 Jul. 2013
• 半導体装置及び半導体装置の製造方法
  Patent right, 福井 孝志; 冨岡 克広; 本久 順一; 原 真二郎
  台湾出願100106528, 23 Feb. 2011
• 半導体装置及び半導体装置の製造方法
  Patent right, 福井 孝志; 冨岡 克広; 本久 順一; 原 真二郎
  米国出願13/581242, 23 Feb. 2011
• 半導体装置及び半導体装置の製造方法
  Patent right, 福井 孝志; 冨岡 克広; 本久 順一; 原 真二郎
  特願2012-501804, 23 Feb. 2011
• 半導体装置及び半導体装置の製造方法
  Patent right, 福井 孝志; 冨岡 克広; 本久 順一; 原 真二郎
  欧州出願11747358.7, 23 Feb. 2011
• 半導体装置及び半導体装置の製造方法
  Patent right, 福井 孝志; 冨岡 克広; 本久 順一; 原 真二郎
  PCT出願PCT/JP2011/053909, 23 Feb. 2011
• トンネル電界効果トランジスタおよびその製造方法
  Patent right, 冨岡 克広; 福井 孝志; 田中 智隆
  米国出願13/499333, 29 Sep. 2010
• トンネル電界効果トランジスタおよびその製造方法
  Patent right, 冨岡 克広; 福井 孝志; 田中 智隆
  韓国出願10-2012-7007578, 29 Sep. 2010
• トンネル電界効果トランジスタおよびその製造方法
  Patent right, 冨岡 克広; 福井 孝志; 田中 智隆
  特願2011-534074, 29 Sep. 2010
• トンネル電界効果トランジスタおよびその製造方法
  Patent right, 冨岡 克広; 福井 孝志; 田中 智隆
  欧州出願10820133.6, 29 Sep. 2010
• トンネル電界効果トランジスタおよびその製造方法
  Patent right, 冨岡 克広; 福井 孝志; 田中 智隆
  PCT出願PCT/JP2010/005862, 29 Sep. 2010
• 発光素子およびその製造方法
  Patent right, 冨岡 克広; 福井 孝志
  米国出願13/513082, 04 Jun. 2010
• 発光素子およびその製造方法
  Patent right, 冨岡 克広; 福井 孝志
  特願2011-544174, 04 Jun. 2010
• 発光素子およびその製造方法
  Patent right, 冨岡 克広; 福井 孝志
  PCT出願 PCT/JP2010/003762, 04 Jun. 2010
• 半導体装置及び半導体装置の製造方法
  Patent right, 本久 順一; 原 真二郎; 福井 孝志; 冨岡 克広
  特願2010-040019, 25 Feb. 2010
• トンネル電界効果トランジスタおよびその製造方法
  Patent right, 冨岡 克広; 福井 孝志; 田中 智隆
  特願2009-273561, 01 Dec. 2009
• 多孔質半導体膜の形成方法
  Patent right
  特許第４２５７４３１号