基于第一性原理的碳化硅界面态机制研究进展

Research Progress of SiO_2/SiC Interface-state Mechanism Based on First-principles Calculation

碳化硅(SiC)金属–氧化物–半导体场效应晶体管(metal-oxide-semiconductor field-effect transistor,MOSFET)具有低导通电阻及高击穿临界场强等特点,在高压开关器件领域有着较为广阔的应用及发展前景。但由于SiC/SiO_2具有较高的界面态密度,使得器件反型沟道电子迁移率过低,从而严重阻碍SiC器件的广泛应用。为有效地控制界面态,回顾了国内外对SiC/SiO_2界面态的第一性原理研究进展,分析界面态的形成机制,讨论近导带边界中高界面态的根本原因,为SiC器件工艺制备提供理论指导。

SiC metal-oxide-semiconductor field-effect transistors（MOSFETs） have been recognized as having broad application and development prospects in the field of high-voltage switching devices for its low on-resistance and high breakdown critical field strength, etc. However, inversion channel electron mobility of the device is too low due to the high interface-state density of SiC/SiO_2, which severely hinders the widespread use of SiC devices. To effectively control the interface state, the research progress of the first principles of SiC/SiO_2 interface-state at home and abroad was introduced in this paper. Also, we analyzed the formation mechanism of the interface state, and discussed the root cause of the high interface-state density near the SiC conduction band. It provides theoretical guidance for the preparation and fabrication procedure of SiC devices.