Effects of surface orientations and polarities on the InN/ZnO heterojunctions band offsets: A first-principles study

Band offsets are calculated between InN and ZnO for both polar-c and nonpolar-a interface orientations through hybrid functionals. The pseudomorphic interfaces are considered by assuming whether unstrained InN or ZnO is taken as the substrate. Periodic superlattices satisfying the electron counting rule are used to model the interfaces. By combining separate interface and bulk calculations, the band offsets are obtained through an electrostatic potential alignment scheme. These band offsets are important to the device designs based on the InN/ZnO heterojunctions. Particularly, for the polar c-plane interface heterojunction, the effects of crystal polarities are discussed in detail. The modeling procedures can be directly applied to the theoretical studies of the heterojunctions between nitrides and ZnO.