DOPING MECHANISMS OF TIN-DOPED INDIUM OXIDE-FILMS

The polycrystalline Sn-doped In2O3 (ITO) films with different Sn concentrations of 0-6.7 wt% (SnO2 Wt%) were prepared by postannealing the amorphous ITO films deposited by highly dense plasma-assisted EB evaporation at the low substrate temperature. These films were confirmed to show the high crystallinity and homogeneous Sn distribution by x-ray diffraction (XRD), scanning electron microscopy, and electron spectroscopy for chemical analysis. The detail XRD pattern of 1.9 wt% Sn concentration film showed the doublet peaks, indicating that the film structure was the mixture of two different lattice parameters (LP); one was +0.18% larger and another was -0.13% smaller than the In2O3 LP. The enlargement and shrinkage of LP could be attributed to the interstitial and the substitutional Sn atoms, respectively.