Electronic structure, formation energies, transition levels, and the concentration of intrinsic defects in wurtzite ZnO were investigated by using the projector augmented wave method in the generalized gradient approximation. Interstitials, vacancies, and antisites in various charge states were considered. Convergence of the formation energies of various intrinsic point defects was checked, and a comparison was made with earlier results. Even though there existed a difference in the calculated formation energies of certain defects, the calculations also showed that O and Zn vacancies were the predominant intrinsic donor and acceptor defects in ZnO; indicating a consistency among the results obtained using differing methods. The O vacancy was not expected to be the main source of strong n-type conductivity in unintentionally doped ZnO, due to its deep level in the band-gap, but it had to be the origin of an experimentally observed visible photoluminescence band centered between 2.3 and 2.5eV.

Convergence of the Formation Energies of Intrinsic Point Defects in Wurtzite ZnO - First-Principles Study by Projector Augmented Wave Method. J.L.Zhao, W.Zhang, X.M.Li, J.W.Feng, X.Shi: Journal of Physics - Condensed Matter, 2006, 18, 1495-508