Investigation of Carbon Interstitials in the Vicinity of the Si02/4H-SiC(0001) Interface

Native defects, including carbon vacancies and interstitials, are understood to be important defects that degrade device performance. In particular, during oxidation to form SiO2dielectric layers, carbon interstitials are thought to be injected into the SiC channels. Using density functional theory, the kinetics of diffusion of interstitial from the SiO2/4H-SiC(0001) interface has been investigated. The results show that the injection of a carbon interstitial from a site at the 4H-SiC-SiO2 interface is hindered by an additional 1 eV relative to the migration barrier of the native defect in bulk 4H-SiC.