Vacancy defects in ZnO induced by electron irradiation were characterized by the Doppler broadening of annihilation radiation measurements together with the local density approximation calculations. Zinc vacancies (VZn) were responsible for positron trapping in the as-irradiated state. These were annealed out below 200C. The further annealing at 400C resulted in the formation of secondary defects attributed to the complexes composed of Zn vacancies and Zn antisites (VZn-ZnO).

Vacancy Defects in Electron-Irradiated ZnO Studied by Doppler Broadening of Annihilation Radiation. Chen, Z.Q., Betsuyaku, K., Kawasuso, A.: Physical Review B, 2008, 77[11], 113204