Characteristics of cubic MgZnO thin films grown by radio frequency reaction magnetron co-sputtering

Cubic MgZnO thin films were prepared on fused quartz substrate by radio frequency (rf) reaction magnetron co-sputtering technique, and composition modulation of cubic MgZnO films could be accomplished by changing rf power on Zn metal target. During growth process crystal quality of our MgZnO films can be improved by increasing the ratio Of O-2/Ar. Unlike reported growth of (1 1 1) plane cubic MgZnO films, our cubic MgZnO films show (2 0 0) plane growth properties. This phenomenon was assigned to a preferred selection growth characteristic of MgZnO on non-crystalline quartz substrate. Band gaps of cubic MgZnO films calculated by empirical formula are different from that obtained in the absorption spectrum. It is suggested that parts of Mg do not contribute to the band gaps of MgxZn1-xO thin films. (C) 2009 Elsevier B.V. All rights reserved.