ZnO thin films were deposited with RF sputtering using pure Zn target. In order to generate oxidation process of Zn, Ar:O-2 gas mixing in (9:1), (7:3) and (5:5) ratios of Ar:O-2 was used. To characterize ZnO thin films thickness and transparency were measured using optical method, and refractive index and band gap energies were calculated. Electrical conductivity of the ZnO thin films was also determined. AFM images were used to determine surface morphology of produced ZnO thin films. (c) 2009 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.