Study on optical constants of ITO:Ag nanocompsite films

Indium tin oxide (ITO) thin films doped with a volume ratio of 0.3% Ag were prepared by sputtering and subsequently annealed in temperatures of 200, 260, 300, 360, and 400 degrees C. The annealed films show increased transmittance in the visible wavelength range. The refractive index n and extinction coefficient k were extracted from simulating the transmittance spectra by using spectroscopic ellipsometry analysis method. The n values apparently increased in the whole wavelength range, but the k values were found to have almost no change in the near ultraviolet region after Ag doping. It is, therefore, proposed that the ITO:Ag combined with an ITO multilayer structure can be applied in special optical devices.