Pioneering development of fundamental technologies for fabrication of wide bandgap III-group oxide/nitride heterostructures

• Project/Area Number: 25289093
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Electronic materials/Electric materials
• Research Institution: National Institute of Information and Communications Technology
• Principal Investigator: Higashiwaki Masataka 国立研究開発法人情報通信研究機構, 未来ICT研究所 グリーンICTデバイス先端開発センター, センター長 (70358927)
• Co-Investigator(Kenkyū-buntansha): 尾沼 猛儀 工学院大学, 先進工学部, 准教授 (10375420) ; 本田 徹 工学院大学, 工学部, 教授 (20251671)
• Co-Investigator(Renkei-kenkyūsha): YAMAGUCHI Tomohiro 工学院大学, 先進工学部, 准教授 (50454517)
• Project Period (FY): 2013-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥17,550,000 (Direct Cost: ¥13,500,000、Indirect Cost: ¥4,050,000); Fiscal Year 2015: ¥5,070,000 (Direct Cost: ¥3,900,000、Indirect Cost: ¥1,170,000); Fiscal Year 2014: ¥5,070,000 (Direct Cost: ¥3,900,000、Indirect Cost: ¥1,170,000); Fiscal Year 2013: ¥7,410,000 (Direct Cost: ¥5,700,000、Indirect Cost: ¥1,710,000)
• Keywords: 分子線エピタキシー / 酸化物 / 窒化物 / 半導体物性 / 先端機能デバイス / MBE

Outline of Final Research Achievements

We challenged to realize two types of novel heterostructures composed of III-oxide and nitride semiconductors. Type-I had structures with channel and barrier layers made of a nitride (GaN) and an oxide (Al2O3) layers, respectively. On the other hand, Type-II structures had an oxide channel (Ga2O3) and a nitride barrier (AlN) layers. As a result of optimization regarding growth sequences and conditions by testing out various substrate treatment processes prior to epitaxial growth and growth conditions for buffer layers, we succeeded in establishing basic molecular beam epitaxy growth technology for both types of structures. Furthermore, from optical characterization, we obtained a lot of new knowledge about undetermined fundamental physical properties of Ga2O3 including its bandgap energy.

Research Products

• [Int'l Joint Research] University of Nebraska, Lincoln(米国)
• [Int'l Joint Research] Linkoping University(スウェーデン)
• [Int'l Joint Research] University of Nebraska, Lincoln/University of California, Santa Barbara/Univeristy of Notre Dame(米国)
• [Int'l Joint Research] University of Cagliari/University of Parma(イタリア)
• [Int'l Joint Research] Linkoping University(スウェーデン)
• [Journal Article] Spectroscopic ellipsometry studies on β-Ga2O3 films and single crystal (2016)
  • Author(s): T. Onuma, S. Saito, K. Sasaki, T. Masui, T. Yamaguchi, T. Honda, A. Kuramata, and M. Higashiwaki
  • Journal Title: Japanese Journal of Applied Physics Volume: 55 Issue: 12 Pages: 1202B2-1202B2
  • DOI: 10.7567/jjap.55.1202b2
  • NAID: 210000147262
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Temperature-dependent exciton resonance energies and their correlation with IR-active optical phonon modes in beta-Ga2O3 single crystals (2016)
  • Author(s): T.Onuma, S.Saito, K.Sasaki, K.Goto, T.Masui, T.Yamaguchi, T.Honda, A.Kuramata, and M.Higashiwaki
  • Journal Title: Applied Physics Letters Volume: 108 Issue: 10 Pages: 1019041-5
  • DOI: 10.1063/1.4943175
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Anisotropy, phonon modes, and free charge carrier parameters in monoclinic beta-gallium oxide single crystals (2016)
  • Author(s): M. Schubert, R. Korlacki, S. Knight, T. Hofmann, S. Schoche, V. Darakc hieva, E. Janzen, B. Monemar, D. Gogova, Q.T. Thieu, R. Togashi, H. Murakami, Y. Kumagai, K. Goto, A. Kuramata, S. Yamakoshi, and M. Higashiwaki
  • Journal Title: Physical Review B Volume: 93 Issue: 12
  • DOI: 10.1103/physrevb.93.125209
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Theoretical and experimental investigation of optical absorption anisotropy in beta-Ga2O3 (2016)
  • Author(s): F. Ricci, F. Boschi, A. Barldi, A. Filippetti, M. Higashiwaki, A. Kuramata, V. Fiorentini, and R. Fornari
  • Journal Title: Journal of Physics: Condensed Matter Volume: 28 Issue: 22 Pages: 224005-224005
  • DOI: 10.1088/0953-8984/28/22/224005
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Valence band ordering in beta-Ga2O3 studied by polarized transmittance and reflectance spectroscopy (2015)
  • Author(s): T.Onuma, S.Saito, K.Sasaki, T.Masui, T.Yamaguchi, T.Honda, and M.Higashiwaki
  • Journal Title: Japanese Journal of Applied Physics Volume: 54 Issue: 11 Pages: 1126011-5
  • DOI: 10.7567/jjap.54.112601
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Impacts of AlOx formation on emission properties of AlN/GaN heterostructures (2015)
  • Author(s): Takeyoshi Onuma, Yohei Sugiura, Tomohiro Yamaguchi, Tohru Honda, and Masataka Higashiwaki
  • Journal Title: Applied Physics Express Volume: 8 Issue: 5 Pages: 0524011-3
  • DOI: 10.7567/apex.8.052401
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Growth of crystallized AlOx on AlN/GaN heterostructures by in-situ RF-MBE (2014)
  • Author(s): Yohei Sugiura, Tohru Honda, Masataka Higashiwaki
  • Journal Title: Journal of Crystal Growth Volume: 405 Pages: 64-67
  • DOI: 10.1016/j.jcrysgro.2014.07.055
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Polarized Raman spectra in β-Ga2O3 single crystals (2014)
  • Author(s): T. Onuma, S. Fujioka, T. Yamaguchi, Y. Itoh, M. Higashiwaki, K. Sasaki, T. Masui, and T. Honda
  • Journal Title: Journal of Crystal Growth Volume: in press Pages: 330-333
  • DOI: 10.1016/j.jcrysgro.2013.12.061
  • Peer Reviewed
• [Journal Article] Correlation between blue luminescence intensity and resistivity in β-Ga2O3 single crystals (2013)
  • Author(s): T. Onuma, S. Fujioka, T. Yamaguchi, M. Higashiwaki, K. Sasaki, T. Masui, and T. Honda
  • Journal Title: Applied Physcs Letters Volume: 103 Issue: 4 Pages: 0419101-3
  • DOI: 10.1063/1.4816759
  • Peer Reviewed
• [Presentation] Optical properties of Ga2O3 films and crystals (2017)
  • Author(s): T. Onuma, S. Saito, K. Sasaki, K. Goto, T. Masui, T. Yamaguchi, T. Honda, A. Kuramata, M. Higashiwaki
  • Organizer: Compound Semiconductor Week 2017 (CSW 2017)
  • Place of Presentation: dbb forum berlin, Berlin, Germany
  • Year and Date: 2017-05-14
  • Int'l Joint Research / Invited
• [Presentation] 単斜晶酸化ガリウム結晶における光学遷移過程 (2017)
  • Author(s): 尾沼 猛儀、齋藤 伸吾、佐々木 公平、後藤 健、増井 建和、山口 智広、本田 徹、倉又 朗人、東脇 正高
  • Organizer: 第64回応用物理学会春季学術講演会 シンポジウム「金属酸化物の結晶物性に迫る」
  • Place of Presentation: 神奈川県横浜市 横浜国際平和会議場（パシフィコ横浜）
  • Year and Date: 2017-03-14
  • Invited
• [Presentation] Effect of nitridation on properties of AlN/β-Ga2O3 composite structures (2017)
  • Author(s): L. Ravikiran、中田 義昭、倉又 朗人、山腰 茂伸、東脇 正高
  • Organizer: 第64回応用物理学会春季学術講演会
  • Place of Presentation: 神奈川県横浜市 横浜国際平和会議場（パシフィコ横浜）
  • Year and Date: 2017-03-14
• [Presentation] β-Ga2O3結晶における光学的異方性の解析 (2017)
  • Author(s): 尾沼 猛儀、山口 智広、本田 徹、佐々木 公平、後藤 健、増井 建和、倉又 朗人、齋藤 伸吾、東脇 正高
  • Organizer: 日本学術振興会161委員会 第98回研究会「ワイドギャップ酸化物半導体β-Ga2O3結晶成長、結晶評価、デバイス応用」
  • Place of Presentation: 滋賀県長浜市 長浜ロイヤルホテル
  • Year and Date: 2017-01-12
  • Invited
• [Presentation] β-Ga2O3薄膜と単結晶の光学定数の比較 (2016)
  • Author(s): 尾沼 猛儀、齋藤 伸吾、佐々木 公平、増井 建和、山口 智広、本田 徹、倉又 朗人、東脇 正高
  • Organizer: 第77回応用物理学会秋季学術講演会
  • Place of Presentation: 新潟県新潟市 朱鷺メッセ
  • Year and Date: 2016-09-13
• [Presentation] Observation of exciton-LO-phonon interaction in β-Ga2O3 single crystals (2016)
  • Author(s): T. Onuma, S. Saito, K. Sasaki, K. Goto, T. Masui, T. Yamaguchi, T. Honda, A. Kuramata, M. Higashiwaki
  • Organizer: German-Japanese Gallium Oxide Technology Meeting 2016
  • Place of Presentation: Leibniz Institute for Crystal Growth, Berlin, Germany
  • Year and Date: 2016-09-07
  • Int'l Joint Research / Invited
• [Presentation] Anisotropic optical constants in β-Ga2O3 single crystal (2016)
  • Author(s): T. Onuma, S. Saito, K. Sasaki, T. Masui, T. Yamaguchi, T. Honda, A. Kuramata, M. Higashiwaki
  • Organizer: 58th Electronic Materials Conference (EMC 2016)
  • Place of Presentation: University of Delaware, Newark, Delaware, USA
  • Year and Date: 2016-06-22
  • Int'l Joint Research
• [Presentation] Beta-Ga2O3結晶における励起子-LOフォノン相互作用 (2016)
  • Author(s): 尾沼猛儀、齋藤伸吾、佐々木公平、後藤健、増井建和、山口智広、本田徹、倉又朗人、東脇正高
  • Organizer: 第63回応用物理学会春季学術講演会
  • Place of Presentation: 東京都目黒区東京工業大学大岡山キャンパス
  • Year and Date: 2016-03-19
• [Presentation] Valence band structure of monoclinic gallium oxide studied by polarized optical measurements (2015)
  • Author(s): T. Onuma, S. Saito, K. Sasaki, K. Goto, T. Masui, T. Yamaguchi, T. Honda, and M. Higashiwaki
  • Organizer: The Collaborative Conference on Crystal Growth 2015 (3CG 2015)
  • Place of Presentation: Eaton Hotel, Kowloon, Hong Kong
  • Year and Date: 2015-12-14
  • Int'l Joint Research / Invited
• [Presentation] Optical anisotropy in (010) plane of beta-Ga2O3 single crystals (2015)
  • Author(s): T. Onuma, S. Saito, K. Sasaki, K. Goto, T. Masui, T. Yamaguchi, T. Honda, and M. Higashiwaki
  • Organizer: 1st International Workshop on Gallium Oxide and Related Materials (IWGO-1)
  • Place of Presentation: 京都府京都市京都大学桂キャンパス
  • Year and Date: 2015-11-03
  • Int'l Joint Research
• [Presentation] Beta-Ga2O3結晶の(010)面における光学的異方性 (2015)
  • Author(s): 尾沼猛儀、齋藤伸吾、佐々木公平、増井建和、山口智広、本田徹、東脇正高
  • Organizer: 第76回応用物理学会秋季学術講演会
  • Place of Presentation: 愛知県名古屋市名古屋国際会議場
  • Year and Date: 2015-09-13
• [Presentation] "Determination of Direct and Indirect Bandgap-energies of beta-Ga2O3 by polarized transmittance and reflectance spectroscopy (2015)
  • Author(s): T. Onuma, S. Saito, K. Sasaki, T. Masui, T. Yamaguchi, T. Honda, and M. Higashiwaki
  • Organizer: 57th Electronic Materials Conference (EMC-57)
  • Place of Presentation: The Ohio State University, Columbus, Ohio, USA
  • Year and Date: 2015-06-24
  • Int'l Joint Research
• [Presentation] Optical anisotropy in beta-Ga2O3 crystals grown by melt-growth methods (2015)
  • Author(s): T. Onuma, S. Saito, K. Sasaki, T. Masui, T. Yamaguchi, T. Honda, and M. Higashiwaki
  • Organizer: International Conference on Light-Emitting Devices and Thier Industrial Applications ’15 (LEDIA ’15)
  • Place of Presentation: 神奈川県横浜市横浜国際平和会議場（パシフィコ横浜）
  • Year and Date: 2015-04-22
  • Int'l Joint Research
• [Presentation] (-201) Ga2O3基板上へのAlN薄膜のRF-MBE成長 (2015)
  • Author(s): 東脇 正高、中田 義昭、倉又 朗人、山腰 茂伸
  • Organizer: 第62回応用物理学会春季学術講演会
  • Place of Presentation: 神奈川県平塚市東海大学湘南キャンパス
  • Year and Date: 2015-03-11 – 2015-03-14
• [Presentation] β-Ga2O3結晶の透過と反射スペクトルの偏光依存性 (2015)
  • Author(s): 尾沼 猛儀、齋藤 伸吾、佐々木 公平、増井 建和、山口 智広、本田 徹、東脇 正高
  • Organizer: 第62回応用物理学会春季学術講演会
  • Place of Presentation: 神奈川県平塚市東海大学湘南キャンパス
  • Year and Date: 2015-03-11 – 2015-03-14
• [Presentation] Ga2O3基板の光学的特性評価 (2014)
  • Author(s): 尾沼 猛儀、山口 智広、伊藤 雄三、本田 徹、佐々木 公平、増井 建和、東脇 正高
  • Organizer: 日本学術振興会第162委員会第91回研究会「酸化物材料の最近の進展」
  • Place of Presentation: 東京都品川区京都大学東京オフィス
  • Year and Date: 2014-09-26
  • Invited
• [Presentation] AlOx/AlN/GaNヘテロ構造の発光特性 (2014)
  • Author(s): 尾沼 猛儀、杉浦 洋平、山口 智広、本田 徹、東脇 正高
  • Organizer: 第75回応用物理学会秋季学術講演会
  • Place of Presentation: 北海道札幌市北海道大学札幌キャンパス
  • Year and Date: 2014-09-17 – 2014-09-20
• [Presentation] In-situ RF-MBE growth of AlOx/AlN/GaN heterostructures (2013)
  • Author(s): Y. Sugiura, T. Yamaguchi, T. Honda, and M. Higashiwaki
  • Organizer: International Symposium on Compound Semiconductors (ISCS 2013)
  • Place of Presentation: 兵庫県神戸市神戸国際会議場
• [Presentation] In-situ RF-MBEによるる窒化物構造上AlOx薄膜の結晶成長 (2013)
  • Author(s): 杉浦 洋平、本田 徹、東脇 正高
  • Organizer: 第5回窒化物半導体結晶成長講演会
  • Place of Presentation: 大阪府吹田市大阪大学吹田キャンパス
• [Presentation] RF-MBE growth of AlOx/AlN/GaN heterostructures (2013)
  • Author(s): 杉浦 洋平、山口 智広、本田 徹、東脇 正高
  • Organizer: 32nd Electronic Materials Syposium
  • Place of Presentation: 滋賀県守山市ラフォーレ琵琶湖
• [Presentation] Polarized Raman spectra in β-Ga2O3 crystals (2013)
  • Author(s): T. Onuma, S. Fujioka, T. Yamaguchi, M. Higashiwaki, K. Sasaki, T. Masui, and T. Honda
  • Organizer: 17th International Conference on Crystal Growth and Epitaxy (ICCGE-17)
  • Place of Presentation: University of Warsaw, Warsaw, Poland
• [Presentation] Crystallized AlOx/AlN/GaN heterostructures grown by plasma-assisted molecular beam epitaxy (2013)
  • Author(s): Y. Sugiura, T. Honda, and M. Higashiwaki
  • Organizer: 10th International Conference on Nitride Semiconductors (ICNS-10)
  • Place of Presentation: Gaylord National Hotel and Convention Center, Washington, D.C., USA
• [Presentation] In-situ RF-MBEによるAlN/GaNヘテロ構造上へのAlOx薄膜成長 (2013)
  • Author(s): 杉浦 洋平、本田 徹、東脇 正高
  • Organizer: 第74回応用物理学会秋季学術講演会
  • Place of Presentation: 京都府京田辺市同志社大学京田辺キャンパス
• [Presentation] β-Ga2O3結晶における青色発光強度と抵抗率の相関 (2013)
  • Author(s): 尾沼 猛儀、藤岡 秀平、山口 智広、東脇 正高、佐々木 公平、増井 建和、本田 徹
  • Organizer: 第74回応用物理学会秋季学術講演会
  • Place of Presentation: 京都府京田辺市同志社大学京田辺キャンパス
• [Book] 次世代パワー半導体の高性能化とその産業展開 (2015)
  • Author(s): 東脇 正高
  • Total Pages: 251
  • Publisher: シーエムシー出版
• [Remarks] 情報通信研究機構 未来ICT研究所 グリーンICTデバイス先端開発センター
  • URL: http://www2.nict.go.jp/green/
• [Remarks] 情報通信研究機構 未来ICT研究所 グリーンICTデバイス先端開発センター
  • URL: http://www2.nict.go.jp/green/index.html
• [Remarks] 情報通信研究機構 未来ICT研究所 グリーンICTデバイス先端開発センター
  • URL: http://www2.nict.go.jp/advanced_ict/green/index.html