Effect of High Temperature Annealing on Conduction-Type ZnO Films Prepared by Direct-Current Magnetron Sputtering.

We experimentally find that the ZnO thin films deposited by dc-magnetron sputtering have different conduction types after annealing at high temperature in different ambient. Hall measurements show that ZnO films annealed at 1100degC in N2 and in O2 ambient become n-type and p-type, respectively. This is due to the generation of different intrinsic defects by annealing in different ambient. X-ray photoelectron spectroscopy and photolumi-nescence measurements indicate that zinc interstitial becomes a main defects after annealing at 1100degC in N2 ambient, and these defects play an important role for n-type conductivity of ZnO. While the ZnO films annealed at 1100degC in O2 ambient, the oxygen antisite contributes ZnO films to p-type. [ABSTRACT FROM AUTHOR]