Preparation And Properties Of ITO Films Prepared By Sol-Gel Method

Indium Tin Oxide (ITO) is a tin-doped oxide semiconductor material. It is widely material of transparent conductive film because of high conductivity and excellent transparency. But most ITO films are manufactured by vacuum vapour deposition and ion sputtering process, which limited its application. In comparison with this, Using InCl₃·4H₂O and SnCl₄·5H₂O as raw materials, ITO transparent thin films were prepared on common glass substrate by sol-gel spin-coating process. The effects of the heat-treatment temperature and the time, and Sn dopant content on the grain size, optical and electrical properties of the ITO thin films were investigated by X-ray diffraction , UV-Vis transmission spectra and four-probe electrical measurement quenching in air and N₂. The surface morphology of the ITO thin films was observed using AFM .The ITO films prepared by inorganic salts method were investigated. The XRD results indicate that the ITO film is a cubic bixbyite structure. During the process of doping, each Sn4+ replaces an In3+ donating a free electron for the conductivity. The AFM's results showed that the ITO films is composed of nanometer-scaled particles. The optimum processing conditions are 11% of Sn dopant content and annealing for 60min at 480℃. Under above optimum conditions, we prepared the ITO films, The average visible transmittance is about 82% and the sheet resistance is about 390?/â–¡with quenching in air. The average visible transmittance is about 81% and the sheet resistance is about 340?/â–¡with quenching in N2.The average grain size is about 50nm.And the properties of ITO films quenching in N2 is better than in air.