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

The formation of the {1bar 210} 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<10bar 11>{1bar 210} configuration is more stable in GaN and InN. In GaN layers, only the 1/2<10bar 11>{1bar 210} configuration was observed. The 1/6<20bar 23> 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<10bar 11>{1bar 210} atomic configuration