Low-Resistivity Indium-Tin-Oxide Transparent Conducting Films: Dependence of Carrier Electron Concentration on Tin Concentration

Indium-Tin-Oxide (ITO, tin-doped In2O3) films with low resistivity (7.7x10(-5) ohm cm) and high carrier electron concentration (1.8x10(21) cm-3) was successfully prepared by spray chemical vapor deposision in air and post-deposition annealing in reducing atmosphere in our previous papers; Y. Sawada et al., Thin Solid Films, 409 (2002) 46-50 and Y. Sawada, Materials Sci. Forum, 437-438 (2003) 23-26. Doping one tin ion generated two carrier electrons at low concentration of tin. The relation between carrier electron concentration and tin concentration are discussed in the present paper to propose a nobel defect model.