Effects of defects and surface structure on oxide film on non-polar 4H-SiC plane

• Project/Area Number: 17K05049
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Crystal engineering
• Research Institution: Japan Fine Ceramics Center
• Principal Investigator: Yukari Ishikawa 一般財団法人ファインセラミックスセンター, その他部局等, 主席研究員 (60416196)
• Co-Investigator(Kenkyū-buntansha): 菅原 義弘 一般財団法人ファインセラミックスセンター, その他部局等, 上級研究員 (70466291) ; 姚 永昭 一般財団法人ファインセラミックスセンター, その他部局等, 上級研究員 (80523935)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2019: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2018: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2017: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000)
• Keywords: 4H-SiC / 非極性面 / 転位 / CL / 積層欠陥 / M面 / 基底面転位 / 部分転位 / GaN / EBIC / TEM / 拡張 / 結晶工学 / 半導体

Outline of Final Research Achievements

We observed the generation and expansion of single Shockley stacking faults which cause the forward voltage drift in 4H-SiC PiN diode from basal plane dislocations in a 4H-SiC from the non-polar plane under electron beam irradiation. We found that 1) not only direct excitation but also indirect excitation which provide electron-hole can generate and expand stacking fault from basal plane dislocation, 2) indirect excitation of partial dislocation is more effective than direct excitation of stacking fault for expand stacking fault and 3) C-core partial dislocation become mobile after supplying a threshold number of electron-hole pairs.

Academic Significance and Societal Importance of the Research Achievements

SiCパワーデバイスの順方向ドリフトの原因となる積層欠陥の生成メカニズムに関して新たな知見を得た。これは、電気自動車、電力変換、電車等社会インフラに必要な電力変換素子の信頼性、性能維持に必要な情報となる。また、学術的には光や電子線の照射によって転位が可動化するメカニズムに新たな知見を加えるものである。転位はデバイスだけではなく材料の力学的特性を決めるものであり、光・放射線照射下（宇宙・原子炉等の加工環境下）での材料物性の変化の予測、解明に役立つことが期待される。

Research Products

• [Journal Article] Observation of dislocations in β-Ga2O3 single-crystal substrates by synchrotron X-ray topography, chemical etching, and transmission electron microscopy (2020)
  • Author(s): Yongzhao Yao, Yoshihiro Sugawara and Yukari Ishikawa
  • Journal Title: Japanese Journal of Applied Physics Volume: 59 Issue: 4 Pages: 045502-045502
  • DOI: 10.35848/1347-4065/ab7dda
  • Peer Reviewed
• [Journal Article] X-ray diffraction and Raman characterization of β-Ga2O3 single crystal grown by edge-defined film-fed growth method (2019)
  • Author(s): Yao, Yongzhao, Sugawara, Yoshihiro, Yukari, Ishikawa,Takahashi, Yumiko, Hirano, Keiichi
  • Journal Title: Journal of Applied Physics Volume: 126 Issue: 20 Pages: 205110-205110
  • DOI: 10.1063/5.0007229
  • Peer Reviewed
• [Journal Article] Expansion of Basal Plane Dislocation in 4H-SiC Epitaxial Layer on A-Plane by Electron Beam Irradiation (2018)
  • Author(s): Masaki Sudo, Yukari Ishikawa, Yongzhao Yao, Yoshihiro Sugawara, and Masashi Kato
  • Journal Title: Materials Science Forum Volume: 924 Pages: 151-154
  • DOI: 10.4028/www.scientific.net/msf.924.151
  • Peer Reviewed
• [Journal Article] Expansion of a single Shockley stacking fault in a 4H-SiC (11-20) epitaxial layer caused by electron beam irradiation (2018)
  • Author(s): Yukari Ishikawa, Masaki Sudo, Yongzhao Yao, Yoshihiro Sugawara, and Masashi Kato
  • Journal Title: Journal of Applied Physics Volume: 123 Issue: 22 Pages: 1-6
  • DOI: 10.1063/1.5026448
  • Peer Reviewed
• [Presentation] HVPE-GaN基板上に形成したビッカース圧痕周囲の転位構造 (2020)
  • Author(s): 石川 由加里、菅原 義弘、横江 大作、姚 永昭
  • Organizer: 2020年第67回応用物理学会春季学術講演会
• [Presentation] Synchrotron X-Ray Topography Observation and Classification of Dislocations in β-Ga2O3 single crystal substrates grown by edge-defined film-fed growth (2019)
  • Author(s): Yao, Yongzhao, Sugawara, Yoshihiro, Yukari, Ishikawa,Takahashi, Yumiko, Hirano, Keiichi
  • Organizer: Yao, Yongzhao, Sugawara, Yoshihiro, Yukari, Ishikawa,Takahashi, Yumiko, Hirano, Keiichi
  • Int'l Joint Research
• [Presentation] Observation and classification of defects in gallium oxide (2019)
  • Author(s): Yao, Yongzhao
  • Organizer: International Workshop on Gallium Oxide and Related Materials
  • Int'l Joint Research
• [Presentation] 4H-SiC, GaNの基底面転位のm面電子線照射による挙動 (2019)
  • Author(s): 石川由加里，須藤正喜，菅原義弘，姚永昭，加藤正史、三好実人、江川孝志
  • Organizer: 2019年第66回応用物理学会春季学術講演会
• [Presentation] 4H-SiCのA面における基底面転位の電子線照射による拡張挙動 (2017)
  • Author(s): 石川由加里，須藤正喜，姚永昭，菅原義弘，加藤正史
  • Organizer: 第78回応用物理学会秋季学術講演会
• [Presentation] 4H-SiC A面電子線励起による基底面転位の拡張挙動 (2017)
  • Author(s): 石川由加里，須藤正喜，姚永昭，菅原義弘，加藤正史
  • Organizer: 先進パワー半導体分科会 第4回講演会
• [Presentation] Expansion of basal plane dislocation in 4H-SiC epitaxial layer on A-plane by electron beam irradiation (2017)
  • Author(s): Masaki Sudo, Yukari Ishikawa, Yong-Zhao Yao, Yoshihiro Sugawara, and Masashi Kato
  • Organizer: 2017 International Conference on Silicon Carbide and Related Materials
  • Int'l Joint Research