First-principles calculations of the energetics of In-terminated (00•1), (00•¯1), (10•1) and (10•¯1) surfaces indicated that In had an appreciable effect upon the relative formation energies of these surfaces. The In-induced changes in the surface energetics permitted the formation of inverted hexagonal pyramid defects having (10•1) facets at the termination of threading defects on the (00•1) surface of pseudomorphic InGaN films. In the case of dislocations which terminated on the InGaN (00•¯1) surface, the calculations predicted that large (10•¯1) faceted defects were not energetically favourable.

Indium-Induced Changes in GaN(0001) Surface Morphology J.E.Northrup, J.Neugebauer: Physical Review B, 1999, 60[12], R8473-6