The electronic properties of Mg-doped perfect SrTiO3 and crystals containing oxygen vacancies systems were investigated by first principles calculation. Dopant formation energy results showed that the Mg atoms preferentially enter the Sr site in SrTiO3. Substitution of Ti by Mg brings some acceptor levels, which introduces the p-type conductivity of SrTiO3. Creation of oxygen vacancies in SrTiO3 introduces donor levels, which could contribute to the n-type conductivity. In SrTiO3 containing oxygen vacancies system, a self-compensation effect will occur when Ti was substituted by Mg, and the system undergoes n-type to p-type transition.

Atomic and Electronic Structures of Mg-Doped Perfect SrTiO3 and Crystals Containing Oxygen Vacancies from First Principles. W.Zeng, T.M.Liu, C.l.Lu, D.J.Liu: Physica B, 2011, 406[8], 1420-8