Reconsideration of interface science and engineering of silicon carbide-based metal-oxide-semiconductor interface

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K18170
• Research Category: Grant-in-Aid for Challenging Research (Pioneering)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 21:Electrical and electronic engineering and related fields
• Research Institution: Osaka University
• Principal Investigator: Watanabe Heiji 大阪大学, 大学院工学研究科, 教授 (90379115)
• Project Period (FY): 2021-07-09 – 2024-03-31
• Keywords: 炭化珪素 / パワーデバイス / MOS構造 / 界面科学

Outline of Final Research Achievements

Silicon carbide (SiC) is a promising semiconductor material for power device applications, and SiC-based metal-oxide-semiconductor field-effect transistors (MOSFETs) are being implemented. However, a large number of defects exist at the interface between the SiC and the gate dielectric (MOS interface), leading to deteriorated device performance and poor long-term reliability. However, details of the interface defects have not yet been revealed, and the quality of SiC MOS interface needs to be further improved for the widespread implementation of SiC power devices. In this study, aiming at understanding the unique nature of the SiC MOS interface and establishing new guidelines for interface engineering, we explored a novel method for fabricating high-quality SiC MOS structure without oxidizing the SiC surface, and characterized specially designed SiC MOS devices for the analysis of interface properties.

Free Research Field

薄膜工学

Academic Significance and Societal Importance of the Research Achievements

熱酸化SiC MOS界面の欠陥については、酸化の進行に伴う炭素不純物の偏析に加えて、SiC半導体のエネルギーバンド構造の特異性を指摘する理論計算結果が報告されている。しかし、これらの影響を系統的に解き明かした報告は皆無であり、本研究は新規ヘテロ界面科学の再構築を目指す取り組みとして学術的にも大きな意義を有している。また、SiCパワーデバイスの高性能化と信頼性向上は、電気エネルギーの高効率利活用に貢献し、省エネ社会実現に向けた最重要課題として位置付けられる。