Characterization of ITO Thin Films Prepared by DC Magnetron Sputtering

Abstract

Transparent and conductive indium-tin oxide (ITO) films were deposited on glass substrates by DC magnetron sputtering method. The optical and electrical characteristics were investigated to achieve optimum growth and resistance conditions. The film crystallinity was characterized by X-ray diffraction (XRD), while the surface resistivity was measured by the four-probe method. It is found that the thin film structure depends on substrate temperature and oxygen pressure, i.e. the resistivity is decreasing with an increase in the deposition temperature. The film transparency increases upon decreasing the deposition time. The optimum growth conditions: DC power - 150W, deposition pressure - 7 × 10-3 mbar, deposition temperature - 200 °C, the gas (Ar and O2) partial pressure ratio - 28:1 and the deposition time - 6 minute. These optimum synthesis conditions resulted in resistivity values of 10 Ohm/? and transmittance ranging between 85 and 95% for the films grown on glass substrate. We conclude that the deposition temperature may improve film resistivity, while the decrease of deposition time leads to an increase the optical transmittance