Heat Treatment Effects of ZnO:Al Thin Films Prepared by Facing-Target-Type Sputtering Method

Abstract
ZnO:Al films were deposited by a facing-target-type method on a glass substrate, which is held at 300°C. The minimum resistivity was obtained with an Al concentration of 1.3%. The decrease of resistivity after the heat treatment of ZnO:Al (1.3%; calculated from area ratio of target) film seems to be mainly attributed to the increase of Hall mobility. The improvement of Hall mobility is not due to the improvement of crystallinity, but it may be due to the decrease of oxygen impurities at interstitial sites.