Low resistivity indium–tin oxide transparent conductive films. I. Effect of introducing H2O gas or H2 gas during direct current magnetron sputtering

Abstract

When an inline sputtering system is used to make conductive transparent ITO film by the direct current (dc) magnetron sputtering method, it was found that the partial gas pressure of H2O affected the properties of deposited films. When the substrate temperature is at or below 200 °C, the control of H2O partial gas pressure is especially important. Using room temperature substrates, an addition of 2×10−5 Torr of H2O in the sputtering process could form ITO films with good repeatability at a low resistivity of 6.0×10−4 Ω cm. By adding H2O gas, it was possible to solve the issue of increased resistivity in thicker films. The films with added H2O gas have H element immersed into the film and have high carrier concentration. Film transmittance stayed constant with or without H2O gas addition. Similar effect was observed by adding H2 gas instead of H2O gas.