Effects of oxygen concentration on characteristics of RF-sputtered In2O3-ZnO thin films

The effects of oxygen concentration on the electrical and optical properties Of In2O3-ZnO films are investigated. In2O3-ZnO films deposited under the pure Ar gas show a resistivity of about 3.8 x 10(-4) Omega .cm, comparable to that of indium-tin-oxide (ITO) films (similar to 10(-4) Omega .cm), and an average transmittance of over 90% in the visible range. Thin films deposited at higher oxygen concentration also show larger absorption at about 400-500 mn compared to those deposited at the oxygen concentration of 0.0%. We propose that it is desirable to use pure Ar gas to obtain films with lower resistivity and higher transmittance in the visible range. Moreover, in the case of films deposited with a higher oxygen concentration, it is found that the resistivity significantly decreases with increasing heat treatment temperature.