Effects of growth temperature and Si doping on the formation of vacancy defects in molecular beam epitaxy GaCrN films were studied by positron annihilation spectroscopy. No vacancy defects were detected in the GaCrN films grown at 700C. In the undoped GaCrN film grown at 540C, vacancy clusters with sizes of V8 to V12 were responsible for positron trapping. Vacancy clusters were much reduced by Si doping, but complexes related to nitrogen vacancies still survived.

Defect Structure of MBE-Grown GaCrN Diluted Magnetic Semiconductor Films. A.Yabuuchi, M.Maekawa, A.Kawasuso, S.Hasegawa, Y.K.Zhou, H.Asahi: Journal of Physics - Conference Series, 2011, 262[1], 012066