First-principles study for self-limiting growth of GaN layers on AlN(0001) surface

Abstract

The GaN thickness dependence of surface structural stability and adsorption behavior of Ga adatom in GaN layers on a AlN(0001) surface are investigated on the basis of first-principles calculations to clarify the self-limiting growth on AlN(0001) surface during metal-organic vapor phase epitaxy. The calculations demonstrate that the stability of reconstructed GaN layers on a AlN(0001) surface is similar to that of a GaN(0001) surface irrespective of the GaN film thickness. Furthermore, we find that the adsorption of a Ga adatom on the AlN(0001) surface easily occurs compared with that on AlN(0001) surface with GaN layers. The difference in the adsorption behavior implies that the growth of GaN layers on a AlN(0001) surface is suppressed. The calculated results provide theoretical guidance for understanding the self-limiting growth of GaN layers, resulting in the formation mechanism of GaN quantum wells.