ITO Films Prepared by Long-throw Magnetron Sputtering without Oxygen Partial Pressure

This study has investigated the influence of the radio frequency (rf) power and working pressure on the properties of indium tin oxide (ITO) thin films, which were prepared by long-throw rf magnetron sputtering technique at room temperature. For 200 nm thick ITO films grown at room temperature in pure argon pressure of 0.27 Pa and sputtering power of 40 W, sheet resistance was 26.6 Ω/sq. and transmittance was higher than 88% (at wavelength 500 nm). An X-ray diffraction analysis of the samples deposited at room temperature revealed a structural change from amorphous to mixed amorphous/polycrystalline structure at (222) and (400) texture with increasing rf power. The surface composition of ITO films was characterized by X-ray photoelectron spectroscopy (XPS). Oxygen atoms in both amorphous and crystalline ITO structures were observed from O 1s XPS spectra.