It was found experimentally that ZnO thin films deposited by dc-magnetron sputtering exhibited differing conduction types after annealing at high temperature in different ambients. Hall measurements showed that ZnO films annealed at 1100C in N2 and in O2 ambients became n-type and p-type, respectively. This was due to the generation of different intrinsic defects by annealing in different ambients. X-ray photo-electron spectroscopy and photoluminescence measurements indicated that zinc interstitials became the main defects after annealing at 1100C in N2 ambient, and these defects played an important role in the n-type conductivity of ZnO.

Effect of High Temperature Annealing on Conduction-Type ZnO Films Prepared by Direct-Current Magnetron Sputtering. L.J.Sun, D.K.He, X.Q.Xu, Z.Zhong, X.P.Wu, B.X.Lin, Z.X.Fu: Chinese Physics Letters, 2010, 27[12], 126802