First principles study of SiC/SiO<inf>2</inf> interfaces towards future power devices

Abstract

We clarify the intrinsic problems of SiC/SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> interfaces by the first principles calculations. The unique nearly free electron like characteristics of SiC conduction band bottom causes unexpected formation of interface states near the conduction band bottoms by process induced strain. These results indicate that strain free process is necessary for fabricating high quality NMOSFET. Another proposal is developing PMOSFET instead of presently popular NMOSFET. Moreover, we also discuss the Vth instability caused by proton diffusion.