It was noted that the surface modification of sapphire (00▪1) by Ga could eliminate multiple rotation domains in ZnO films. The existence of Ga at ZnO/sapphire interfaces was confirmed by X-ray energy dispersive spectroscopy in a transmission electron microscope. The atomic detail of mismatch dislocations at interfaces was imaged by high-resolution transmission electron microscopy. Within the ZnO film, there was a high density of stacking faults. Both the pure gliding of ZnO (00▪1) planes, and the condensation of vacancies or interstitials, were possible mechanisms for generating stacking faults.

Microstructure and Crystal Defects in Epitaxial ZnO Film Grown on Ga Modified (0001) Sapphire Surface. H.P.Sun, X.Q.Pan, X.L.Du, Z.X.Mei, Z.Q.Zeng, Q.K.Xue: Applied Physics Letters, 2004, 85[19], 4385-7