Structure and stoichiometry of (0001) 4H–SiC/oxide interface

Abstract

The 4H–SiC/SiO2 interface is a major obstacle that hampers SiC device applications. The nature of the transition region stoichiometry and structure need to be elucidated to both understand and improve such devices. In this paper, we use medium energy ion scattering on device grade structures to examine critical aspects of this dielectric/semiconductor structure. Our findings indicate no excess C greater than 1.8×1014 cm−2 from the oxide surface down to a few monolayers beneath the SiC/SiO2 interface, setting limits on the previously predicted nonstoichiometric transition region on the dielectric side.