| Indium tin oxide (ITO) film is polycrystal with bbc structure. The semi-conducting mechanism of ITO is attributed to doping with Sn and to oxygen vacancies. ITO films possess the predominant electrical and optical properties such as wide band, low resistance, and high transparence in the visible spectrum, that make them have wide applications in the fields of solar cell and optoelectronic devices as the transparent electrodes.In this work, ITO thin films were prepared with thermal evaporation and electron beam evaporation, which was used as the front electrode of silicon based thin film solar cells with nip structure. The best technological conditions were obtained by optimizing, which are, oxygen pressure: 0.13Pa, substrate temperature: 160℃and deposition rate: 0.01nm/s. The best film with transmittance of 90% in the visible range and the resistivity of 4.7×10-4Ω·cm were achieved. The experimental results also confirmed that oxygen vacant and the doped concentration of Sn make significant effects on optical and electrical properties of ITO film.For the sake of the best antireflection, the optimized thickness of ITO film for front electrode of nip structure solar cells is 90nm by theories and experimental analysis. The ITO thin films were used as the front electrode of amorphous silicon solar cells, microcrystalline silicon solar cells and a-Si:H/μc-Si:H tandem solar cells with nip structure, and good device performances were achieved.
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