Valence-band offsets at strained semiconductor heterojunctions

Abstract

Valence-band offsets at lattice mismatched semiconductor heterojunctions are studied by using the interface-bond-polarity model with tight-binding approximation. The interface dipoles for lattice mismatched (001) III-V/IV heterojunctions are calculated based on the polarity of individual bond. It is found that the valence-band discontinuities depend strongly upon both of the strain conditions and the interface bond structures. An improved agreement of the calculated valence-band offsets with that of experimental measurement can be obtained by taking account of the strain effect and the interface dipole correction simultaneously.