溶胶凝胶法制备的ITO薄膜电学及光学性能的研究

Electrical and optical properties of pransparent conductive ITO thin films prepared by the sol-gel process

以无机盐为出发原料,采用溶胶 凝胶法制备了氧化铟锡(ITO)透明导电薄膜。进一步研究了热处理气氛、温度、Sn掺杂量对In2O3薄膜电学及光学性能的影响。分别在氮气、真空和空气3种环境下对薄膜进行热处理,结果表明真空热处理后薄膜的导电性最好。研究了薄膜方块电阻随锡掺杂量的变化,发现薄膜的方阻随掺锡量的增加先减小后增加,并在掺杂量为7mol%左右时达到最低;另外探讨了热处理温度对薄膜光电性能的影响,结果发现薄膜方块电阻随热处理温度的升高而减小,且热处理温度高于700℃后变化不显著,薄膜在可见光区平均透过率随热处理温度升高呈上升趋势。本研究所制得的薄膜可见光区(400～800nm)平均透过率可达85%、方阻约为66Ω。

Indium tin oxide (ITO) thin films have been prepared by a sol-gel process using inorganic metal salts as raw materials. The effects of heat-treatment atmosphere, temperature and Sn dopant content on the electrical and optical properties of In_2O_3 thin films were investigated. The ITO thin films were heat-treated in nitrogen, vacuum and air, respectively. The test results revealed that heat treatment in vacuum was optimum. From the study of the effects of Sn dopant content on electrical and optical properties, it was found that the resistance decreased with increasing Sn content up to 7%, and at 7% had the lowest resistance and then increased. The effects of the heat-treatment temperature on electrical and optical properties were discussed. It revealed that the sheet resistance decreased with increasing heat-treatment temperature up to 700℃ and then it changed weakly .The transparency increased with increasing heat-treatment temperature. The optimized ITO thin films exhibit an average visible solar transmission of around 85% at the wavelength range of 400～800nm and a sheet resistance of around 66Ω.