By using first-principles calculations, the self-diffusion coefficient of Zn in ZnO was derived as a function of the chemical potential and Fermi level. Density functional calculations, combined with the climbing image nudged elastic band method, were used to determine the migration barriers to vacancy, interstitial and interstitialcy jumps. It was found that Zn interstitials preferentially diffused to second-nearest neighbor positions. They became mobile at temperatures as low as 90 to 130K, and therefore allowed rapid defect annealing. Under predominantly O-rich and n-type conditions, self-diffusion occurred via a vacancy mechanism.

Diffusion of Zinc Vacancies and Interstitials in Zinc Oxide. P.Erhart, K.Albe: Applied Physics Letters, 2006, 88[20], 201918 (3pp)