Surface passivation and insulated gate structures for nitride-based semiconductor devices using mist-CVD method

• Project/Area Number: 19K04473
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 21050:Electric and electronic materials-related
• Research Institution: Kumamoto University
• Principal Investigator: Yatabe Zenji 熊本大学, 大学院先端科学研究部(工), 准教授 (00621773)
• Co-Investigator(Kenkyū-buntansha): ASUBAR JOEL 福井大学, 学術研究院工学系部門, 准教授 (10574220) ; 末吉 哲郎 九州産業大学, 理工学部, 准教授 (20315287) ; 中村 有水 熊本大学, 大学院先端科学研究部(工), 教授 (00381004)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Project Status: Completed (Fiscal Year 2021)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2021: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2020: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2019: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000)
• Keywords: ミストCVD / ゲート絶縁膜 / 表面パッシベーション / 窒化物半導体 / 高電子移動度トランジスタ / パワーデバイス / 高周波デバイス / 窒化ガリウム / 電子準位 / トランジスタ

Outline of Research at the Start

低コストで酸化物薄膜が形成可能なミスト化学気相成長(ミストCVD)法を用いて、窒化ガリウム(GaN)系半導体デバイス、特にAlGaN/GaNヘテロ構造の表面パッシベーション膜、およびゲート絶縁膜を作製する。さらに絶縁膜/半導体界面特性を詳細な解析により明らかにし、界面準位密度を極限まで低減した、低コストな絶縁膜堆積プロセス技術の確立を目指す。

Outline of Final Research Achievements

We have developed a gate insulator deposition process for AlGaN/GaN metal-insulator-semiconductor (MIS-HEMTs) using cost-effective and environmental-friendly mist chemical vapor deposition (mist-CVD) method. Mist-deposited gate insulators deposited using optimum condition exhibited characteristics that are comparable to those reported from high-quality amorphous films prepared by the more conventional method of atomic layer deposition (ALD). In addition, we obtained good transistor characteristics from the fabricated devices suggesting high interfacial quality of the resulting insulator/AlGaN interface. These results demonstrate the potential and viability of non-vacuum mist-CVD technique in the development of high-performance AlGaN/GaN-based MIS-HEMTs.

Academic Significance and Societal Importance of the Research Achievements

ミストCVD法は、ALD法など従来の絶縁膜形成プロセスと比較して大掛かりな真空装置を必要としない大気圧下でのプロセスであり、従来手法と比較し低コストで環境負荷が低いプロセスである。本研究課題で得られた成果はSiやGaAsに代わる次世代電力変換用トランジスタ・高周波デバイスとして注目されているGaN系トランジスタの低コスト化、また動作安定性・信頼性向上に繋がると期待される。

Research Products

• [Int'l Joint Research] Slovak Academy of Sciences(スロバキア)
• [Journal Article] GaN-based MIS-HEMTs with Al2O3 dielectric deposited by low-cost and environmental-friendly mist-CVD technique (2021)
  • Author(s): Rui Shan Low, Joel T. Asubar, Ali Baratov, Shunsuke Kamiya, Itsuki Nagase, Shun Urano, Shinsaku Kawabata, Hirokuni Tokuda, Masaaki Kuzuhara, Yusui Nakamura, Kenta Naito, Tomohiro Motoyama, Zenji Yatabe
  • Journal Title: Applied Physics Express Volume: 14 Issue: 3 Pages: 031004-031004
  • DOI: 10.35848/1882-0786/abe19e
  • NAID: 120007160996
  • Peer Reviewed / Open Access
• [Journal Article] Controlling surface/interface states in GaN-based transistors: Surface model, insulated gate, and surface passivation (2021)
  • Author(s): Joel T. Asubar, Zenji Yatabe, Dagmar Gregusova, Tamotsu Hashizume
  • Journal Title: Journal of Applied Physics Volume: 129 Issue: 12 Pages: 121102-121102
  • DOI: 10.1063/5.0039564
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Synthesis and characterization of mist chemical vapor deposited aluminum titanium oxide films (2019)
  • Author(s): Zenji, Yatabe, Koshi Nishiyama, Takaaki Tsuda, Kazuki Nishimura, Yusui Nakamura
  • Journal Title: Japanese Journal of Applied Physics Volume: 58 Issue: 7 Pages: 070905-070905
  • DOI: 10.7567/1347-4065/ab29e3
  • NAID: 120006951248
  • Peer Reviewed
• [Presentation] Mist-Al2O3とALD-Al2O3を絶縁膜としたAlGaN/GaN MIS-HEMTs (2022)
  • Author(s): 浦野 駿, アスバル ジョエル, ロウ ルイシャン, ムハンマド ファリス, 石黒 真輝, 永瀬 樹, バラトフ アリ, 本山 智洋, 中村 有水, 葛原 正明, 谷田部 然治
  • Organizer: 第69回応用物理学会春季学術講演会
• [Presentation] ミストCVD法により堆積したAl2O3絶縁膜の評価とmist-Al2O3/AlGaN/GaN MOS-HEMTへの応用 (2022)
  • Author(s): 本山 智洋, 浦野 駿, バラトフ アリ, 中村 有水, 葛原 正明, アスバル ジョエル, 谷田部 然治
  • Organizer: 第69回応用物理学会春季学術講演会
• [Presentation] Recessed gate GaN-based MIS-HEMTs with Al2O3 gate dielectric deposited by mist-CVD method (2021)
  • Author(s): M. Ishiguro, S. Urano, R. S. Low, M. Faris, I. Nagase, A. Baratov, J. T. Asubar, T. Motoyama, Y. Nakamura, Z. Yatabe, M. Kuzuhara
  • Organizer: The 2021 International Meeting for Future of Electron Devices, Kansai (IMFEDK 2021)
  • Int'l Joint Research
• [Presentation] Electrical properties of GaN-based MISHEMTs with Al2O3 gate insulator deposited by ALD and mist-CVD techniques (2021)
  • Author(s): S. Urano, R. S. Low, M. Faris, M. Ishiguro, I. Nagase, A. Baratov, J. T. Asubar, T. Motoyama, Y. Nakamura, Z. Yatabe, M. Kuzuhara
  • Organizer: The 2021 International Meeting for Future of Electron Devices, Kansai (IMFEDK 2021)
  • Int'l Joint Research
• [Presentation] Mist chemical vapor deposited-Al2O3/AlGaN interfacial characterization for GaN MIS-HEMTs (2021)
  • Author(s): Tomohiro Motoyama, Zenji Yatabe, Yusui Nakamura, Ali Baratov, Rui Shan Low, Shun Urano, Joel T. Asubar, Masaaki Kuzuhara
  • Organizer: The 2021 International Meeting for Future of Electron Devices, Kansai (IMFEDK 2021)
  • Int'l Joint Research
• [Presentation] ミストCVD法により作製したAl2O3薄膜とGaN系MIS-HEMTへの応用 (2021)
  • Author(s): 本山 智洋, Ali Baratov, Rui Shan Low, 浦野 駿, 中村 有水, 葛原 正明, Joel T. Asubar, 谷田部 然治
  • Organizer: 2021年日本表面真空学会学術講演会
• [Presentation] ミストCVD法によるAl2O3絶縁膜を用いたAlGaN/GaN MIS-HEMTの作製と評価 (2021)
  • Author(s): 本山 智洋, Ali Baratov, Rui Shan Low, 浦野 駿, 中村 有水, 葛原 正明, 谷田部 然治, Joel T. Asubar
  • Organizer: 第10回TIAパワーエレクトロニクス・サマースクール
• [Presentation] Characterization of mist-CVD deposited Al2O3 films on AlGaN/GaN heterostructures (2020)
  • Author(s): Tomohiro Motoyama, Kenta Naito, Yusui Nakamura, Zenji Yatabe, Rui Shan Low, Itsuki Nagase, Ali Baratov, Hirokuni Tokuda, Masaaki Kuzuhara, Joel T. Asubar
  • Organizer: IEEE IMFEDK 2020 Satellite event
  • Invited
• [Presentation] Mist-CVD法によるAl2O3絶縁膜を用いたAlGaN/GaN MIS-HEMTの電気特性 (2020)
  • Author(s): ロー ルイ シャン, 永瀬 樹, バラトフ アリ, アスバル ジョエル タクラ, 徳田 博邦, 葛原 正明, 谷田部 然治, 内藤 健太, 本山 智洋, 中村 有水
  • Organizer: 電子情報通信学会 電子デバイス研究会
• [Presentation] ミストCVD法による4-nm Al2O3ゲート絶縁膜を用いたAlGaN/GaN MIS-HEMTの電気特性 (2020)
  • Author(s): Low Rui Shan, 河端 晋作, Joel T. Asubar, 徳田 博邦, 葛原 正明, 谷田部 然治, 内藤 健太, 西村 和樹, 中村 有水
  • Organizer: 第67回応用物理学会春季学術講演会
• [Presentation] Formation of amorphous Al2O3 thin films by mist chemical vapor deposition (2019)
  • Author(s): Kazuki Nishimura, Kenta Naito, Zenji Yatabe, Yusui Nakamura
  • Organizer: 14th International Student Conference on Advanced Science and Technology 2019 (ICAST 2019)
• [Presentation] Al2O3 thin films deposited by mist-CVD for gate insulator application in GaN-based devices (2019)
  • Author(s): Kenta Naito, Kazuki Nishimura, Zenji Yatabe, Joel T. Asubar, Yusui Nakamura
  • Organizer: The 4th Asian Applied Physics Conference (Asian-APC)
  • Int'l Joint Research
• [Presentation] Characterization of Al1-xTixOy thin films deposited by mist-CVD (2019)
  • Author(s): Zenji Yatabe, Koshi Nishiyama, Kazuki Nishimura, Yusui Nakamura
  • Organizer: 2019 International Conference on Solid State Devices and Materials (SSDM2019)
  • Int'l Joint Research
• [Presentation] Characterization of AlxTi1-xOy thin films synthesized using mist-CVD (2019)
  • Author(s): Zenji Yatabe, Koshi Nishiyama, Kazuki Nishimura, Yusui Nakamura
  • Organizer: 13th Topical Workshop on Heterostructure Microelectronics (TWHM 2019)
  • Int'l Joint Research
• [Presentation] Synthesis and characterization of AlTiO films by mist-CVD (2019)
  • Author(s): Zenji Yatabe, Koshi Nishiyama, Takaaki Tsuda, Kazuki Nishimura, Yusui Nakamura
  • Organizer: Compound Semiconductor Week 2019 (CSW2019)
  • Int'l Joint Research
• [Presentation] Characterization of amorphous aluminium oxide thin films synthesized by mist-CVD (2019)
  • Author(s): Zenji Yatabe, Koshi Nishiyama, Takaaki Tsuda, Kazuki Nishimura, Yusui Nakamura
  • Organizer: Compound Semiconductor Week 2019 (CSW2019)
  • Int'l Joint Research
• [Remarks] researchmap
  • URL: https://researchmap.jp/zenji.yatabe
• [Remarks] researchmap
  • URL: https://researchmap.jp/zenji.yatabe/