Elucidation of defects at SiC/SiO2 interfaces by electrical and spectroscopic measurements

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K20429
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0302:Electrical and electronic engineering and related fields
• Research Institution: Osaka University
• Principal Investigator: Kobayashi Takuma 大阪大学, 大学院工学研究科, 助教 (20827711)
• Project Period (FY): 2021-08-30 – 2023-03-31
• Keywords: 炭化珪素（SiC） / 二酸化珪素（SiO2） / 電界効果トランジスタ（MOSFET） / パワーデバイス / 界面欠陥 / 窒化 / 信頼性

Outline of Final Research Achievements

Silicon carbide (SiC) is well-suited for power device applications because of its wide bandgap and high critical electric field. The aim of this study was to understand the factors that dominate the performance and reliability of metal-oxide-semiconductor (MOS) devices. It was found that, while nitridation in nitric oxide (NO) is effective in passivating the interface defects, it induces additional traps that are activated by electrical stress or ultraviolet light irradiation.

Free Research Field

半導体デバイス

Academic Significance and Societal Importance of the Research Achievements

本研究では、SiO2/SiC構造の詳細な電気的評価および物理分析（X線光電子分光法）を実施し、SiO2膜への過剰窒素導入がMOSデバイスの信頼性および安定性を劣化させることを指摘した。逆に言えば、膜中へ過剰窒素を導入しない窒化技術は、性能と信頼性を両立するSiC MOSデバイス実現の鍵となり得る。本研究で得られた知見は高性能・信頼性SiC MOSデバイスを実現する上で重要なものである。