ZnO:N thin films were deposited on sapphire substrate by metal organic chemical vapor deposition with NH3 as N-doping sources. The reproducible p-type ZnO:N film with hole concentration of similar to 10(17) cm(-3) was successfully achieved by subsequent in situ thermal annealing in N2O plasma protective ambient, while only weak p-type ZnO:N film with remarkably lower hole concentration of similar to 10(15) cm(-3) was obtained by annealing in O-2 ambient. To understand the mechanism of the p-type doping behavior of ZnO:N film, X-ray photoelectron spectroscopy (XPS) and soft X-ray absorption near-edge spectroscopy (XANES) measurements have been applied to investigate the local electronic structure and chemical states of nitrogen atoms in ZnO:N films. (c) 2010 Elsevier B.V. All rights reserved.