Microstructure and crystal defects in epitaxial ZnOZnO film grown on GaGa modified (0001) sapphire surface

Abstract

Surface modification of sapphire (0001) by GaGa can eliminate multiple rotation domains in ZnOZnO films. The existence of GaGa at ZnOZnO∕sapphire interface was confirmed by x-ray energy dispersive spectroscopy in a transmission electron microscope. Atomic detail of mismatch dislocations at interface was imaged by high resolution transmission electron microscopy. Inside the ZnOZnO film, there is a high density of stacking fault. Both pure gliding of ZnO (0001)ZnO (0001) plane and condensation of vacancies or interstatials are possible mechanisms to generate the stacking fault.