Influence of temperature and layers on the characterization of ITO films

In this paper, the effects of high heating temperature on electrical and optical properties of transparent indium tin oxide (ITO) films were investigated, which is a topic that has received little attention from previous studies. Uniform and transparent indium tin oxide (ITO) films were deposited onto quartz glass substrates through a sol–gel process. Specifically, the microstructure and phase of the films were analyzed by AFM, AES, and XRD. The sheet resistance and optical transmittance of the films were measured using the four-point probe method and spectrophotometer, respectively. The grain size of the ITO film was refined when it heated at 800 °C. The influence of coating layers on electrical and optical properties was also discussed. With the rise of heating temperature from 400 to 800 °C, the optical transmittance of the films climbed from 76 to 93% (750 °C). With the increase of dip-coating layers from 3 to 7, their sheet resistance varied from 642.1 to 241.0 Ω/□.