Formation and stability of the prismatic stacking faultin wurtzite (Al,Ga,In) nitrides

Abstract

The formation of the {1 10} stacking fault, which has two atomic configurations in wurtzite (Ga,Al,In)N, has been investigated by high resolution electron microscopy and energetic calculations. It originates from steps at the SiC surface and it can form on a flat (0001) sapphire surface. A modified Stillinger-Weber potential was used in order to investigate the relative stability of the two atomic configurations. They have comparable energy in AlN, whereas the 1/2<10 1>{1 10} configuration is more stable in GaN and InN. In GaN layers, only the 1/2<10 1>{1 10} configuration was observed. The 1/6<20 3> configuration was found in small areas inside the AlN buffer layer where it folded rapidly to the basal plane, and when back into the prismatic plane, it took the 1/2<10 1>{1 10} atomic configuration.