Dependence of carrier concentrations on oxygen pressure for Ga-doped ZnO prepared by ion plating method

Transparent and conductive Ga-doped ZnO films have been deposited at a glass substrate temperature of 200 degreesC using an ion plating system. The resistivity as low as 2.7 X 10(-4) Omega cm with a high carrier concentration of 8 X 10(20) cm(-3), Hall mobility of 27 cm(2) (V s)(-1) and high average transmittance above 90% in the visible range were obtained from the film deposited under reducing conditions using ZnO:Ga2O3 tablets with a Ga2O3 content of 3 wt.%. Under reducing conditions, carrier concentration decreases very slowly with increasing oxygen partial pressure. Excess oxygen partial pressure substantially decreases both carrier concentration and Hall mobility in the films. (C) 2003 Elsevier B.V. All rights reserved.