Effects of film thickness and sputtering power on properties of ITO thin films deposited by RF magnetron sputtering without oxygen

In this work, indium tin oxide (ITO) thin films were grown on a glass substrate without introducing oxygen into the growth environment using RF magnetron sputtering technique. The dependence of surface morphological, optical and electrical properties at different film thicknesses and sputtering RF power were investigated. Results showed that these properties were strongly influenced by the film thickness and sputtering RF power. It was found that the resistivity, sheet resistance and optical transmittance of ITO thin films deposited on glass substrate decreased as film thickness increased from 75 to 225 nm while the surface roughness and optical bandgap increased. The optimum properties were obtained for ITO films 225 nm thick grown at 250 W RF power. This has revealed an excellent figure of merit of (38.4 x 10(-4) Omega(-1)) with average transmittance (83.3 %), resistivity (9.4 x 10(-4) Omega cm), and carrier concentration (6.1 x 10(20) cm(-3)). These ITO films are suitable for use in solar cells applications.