Valence-Band Offset at the Zn-P Interface Between ZnSe and III-V Wide Gap Semiconductor Alloys: A First-Principles Investigation

We present a first-principles calculation of the valence-band offset at the (001) interface between ZnSe and III-V lattice-matched alloys based on Al, Ca, In, P elements, namely Al0.5In0. 5P and Ga0.1n0.5P. Among the different possible interface geometries we have focused on the P-terminated alloy in contact with the Zn-terminated ZnSe crystal. The results of this study show the existence of a very low band offset at the abrupt interface, both for the ideal geometry and for the relaxed atomic positions. The investigation of the electronic interface band structure reveals the presence of a low-lying half-filled interface band related to the Zn-P bond.