SiC UMOSFET 구조에 따른 온도 신뢰성 분석

국문 초록 (Abstract)

SiC 기반 소자는 silicon 소자 대비 1200V 이상의 고전압 환경에서 우수하게 동작하며 특히 매우 높은 온도에서 안정적인 특성을 보여준다. 따라서 최근 1700V급 UMOSFET이 전기 자동차, 항공기 등의 전력시스템의 사용을 목표로 활발하게 연구개발 되고 있다. 본 논문에서는 최근 연구되고 있는 세 종류의 1700급 UMOSFET-Conventional UMOSFET (C-UMOSFET), Source Trench UMOSFET (ST-UMOSFET), Local Floating Superjunction UMOSFET (LFS-UMOSFET)-에 대해 온도변화(300K-600K)에 따른 전력소자에서 중요한 변수 (breakdown voltage(BV), on-resistance(Ron), threshold voltage(vth), transconductance(gm))의 신뢰성 특성을 비교 분석하였다. 세 소자 모두 온도 증가에 따른 BV 증가, Ron 증가, vth 감소, gm 감소를 확인하였다. 그러나 세 소자의 구조 차이에 따라 BV, Ron vth, gm 변화에 차이가 있어 그 정도 및 원인에 대해 비교 분석하였다. 모든 결과는 sentaurus TCAD을 통해 simulation 되었다.

다국어 초록 (Multilingual Abstract)

SiC-based devices perform well in high-voltage environments of more than 1200V compared to silicon devices, and are particularly stable at very high temperatures. Therefore, 1700V UMOSFET has been actively researched and developed for the use of electric power systems such as electric vehicles and aircrafts. In this paper, we analysed thermal variations of critical variables (breakdown voltage (BV), on-resistance (Ron), threshold voltage (vth), and transconductance (gm)) for the three type 1700V UMOSFETs-Conventional UMOSFET (C-UMOSFET), Source Trench UMOSFET (STUMOSFET), and Local Floating Superjunction UMOSFET (LFS-UMOSFET). All three devices showed BV increase, Ron increase, vth decrease, and gm decrease with increasing temperature. However, there are differences in BV, vth, gm, according to the structural differences of the three devices, and the degree and cause of the analysis were compared. All results were simulated using sentaurus TCAD.

목차 (Table of Contents)

• Abstract
• 요약
• Ⅰ. 배경
• Ⅱ. SiC UMOSFET 구조
• Ⅲ. SiC UMOSFET 구조별 온도에 따른 신뢰성 분석
• Ⅳ. 결론
• References

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