Influence of the aluminum and indium concentrations on the electrical resistivity and transmittance properties of InAlZnO thin films

Abstract

InAlZnO films were deposited on glass substrates by sputtering InZnO (In2O3-10 wt% ZnO) and AlZnO (3 wt% AI2O 3-97 wt% ZnO) targets simultaneously at room temperature using a DC and AC magnetron cosputtering system. The concentration of Al in the film was varied by using different DC powers for sputtering the InZnO target with the AC power for sputtering the AlZnO target fixed. It has been found that the total concentration of Al and In in the InAlZnO films tends to be maintained constant below a certain Al doping concentration. It has been found that the electrical resistivity of the InZnO film can be decreased by doping Al the concentration of which is higher than a certain lower limit. The cause of the decrease in the resistivity of InZnO by doping 5.2 mol% Al are discussed. The optical transmittance has been found to be also enhanced in all the wavelength range except the range from 410-190 nm by doping 5.2 mol% Al. © 2009 The Ceramic Society of Japan. All rights reserved.