Effect of oxygen partial pressure on optical and electrical properties of co‐sputtered amorphous zinc indium tin oxide thin films

Abstract

Abstract Transparent thin films of amorphous zinc indium tin oxide were prepared at room temperature by co‐sputtering of zinc oxide and indium tin oxide. Effect of oxygen partial pressure on the optical and electrical properties of amorphous zinc indium tin oxide thin films were investigated. Conductivity, carrier concentration and Hall mobility showed strong dependence on the oxygen partial pressure and these parameters decreased with the increase of oxygen pressure. The effect of subgap states caused a sharp difference in measured optical band gap values between the films deposited with and without oxygen partial pressure. Carrier transport studies were carried out by temperature dependent conductivity measurements. At low electron density, the conductivity showed thermally activated behaviour and at higher carrier concentrations it changed to almost degenerate band conduction. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)