The energies of basal-plane stacking faults in wurtzites were determined by using a 1-dimensional Ising-type model which incorporated effective layer-layer interactions that were based upon density-functional theory calculations. The stacking-fault energies were found to be largest for AlN and smallest for GaN. This was consistent with density-functional results for wurtzite/zincblende energy differences. Estimates were also obtained for stacking-fault energies in the zincblende structure. The values were negative, in agreement with the observation that nominal zincblende films typically contained a large number of stacking faults. A related result was that hexagonal structures with stacking sequences that repeated after 4 or 6 bilayers had lower energies than zincblende, for all 3 compounds.

A.F.Wright: Journal of Applied Physics, 1997, 82[10], 5259-61