MgxZn1-xO thin films were deposited on quartz substrates by RF magnetron sputtering. The effect of post-annealing temperature on structural, optical, and electrical properties was investigated with the annealing temperatures increasing from 450 to 750 degrees C. The crystallinity of MgxZn1-xO film annealed at 650 degrees C was significantly improved while the film annealed at 750 degrees C showed little improvement. The electrical properties degraded with the increase of annealing temperature. The annealing temperature seemed to impact the E-g value of MgxZn1-xO thin films because of the variation of carrier concentration. Crown Copyright (C) 2010 Published by Elsevier B.V. All rights reserved.