Influence of RF Power on Optical and Surface Properties of the ZnO Thin Films Deposited by Magnetron Sputtering

The influences of the effects of sputtering power on the optical and structural properties of ZnO thin films were investigated. The ZnO layers were deposited on glass slides by RF magnetron sputtering. RF sputtering powers were adjust to 150 W and 250 W. Optical analysis and tools and methods were used for the comparison of the optical and surface properties. The results show that sputtering powers have affected the optical and surface properties. The band gap variations of ZnO thin films are observed. The samples are transparent. The roughness values of sample grown at 250 W are increased threefold in comparison with sample grown at 150 W while RF power is increased. Furthermore, surface contact angle was decreased to one-half of its values obtained at low RF power. This value is close to theoretical limit of contact angle. Obtained results show that surface properties of the layers can changed by RF power, but optical properties are slightly different.