Degradation of 6H-SiC MOS capacitors operated at high temperatures

6H-SiC MOS capacitors were operated at temperatures above 600K under negati ve bias. Enhancement of energetically shallow and deep interface states at n/p-type SiC/SiO2 structures and of a fixed charge are observed, which can partially be passivated by a hydrogen treatment. The generation and passiva tion of the fixed charge is explained in the framework of the "negative-bia s-temperature instability" originally proposed for Si-based MOS capacitors.