Effect of RF Sputtering Power and Deposition Time on Optical and Electrical Properties of Indium Tin Oxide Thin Film

Indium tin oxide (ITO) films are widely used as transparent conducting electrodes in solar cells, gas sensors, and car windows because of their high electrical conductivity and good optical transparency in the visible region. In this work, ITO thin films were prepared by cathodic radio-frequency (RF) sputtering using an ITO target with 90% In2O3 and 10% SnO2. The structural properties were studied by X-ray diffraction (XRD), scanning electronic microscopy (SEM), and X-ray reflectometry (XRR). Electrical measurements were performed by applying the four-point method and studying the Hall Effect. Finally, optical properties were taken by the UV-Vis-NIR spectrophotometry. The effect of the RF power and deposition time on optical and electrical properties was investigated. It is shown that by using a RF power of 110-80 W, one can prepare crystalline samples with low resistivity, which is an aimed property for TCO semiconductors. Electrical measurements revealed that the resistivity decreases by increasing the RF power and/or the deposition time.