The effect of post-annealing on Indium Tin Oxide thin films by magnetron sputtering method

Abstract We report effects of post-annealing on Indium Tin Oxide (ITO) thin films by their physical, electrical, optical, and electronic properties. Carrier concentrations increase up to annealing temperatures of 400 °C, and then decrease at higher annealing temperatures. Burstein–Moss effect occurs as a function of annealing temperature with the highest optical bandgap of 4.17 eV achieved at 400 °C. X-ray photoelectron spectroscopy revealed a ∼0.3 eV shift in the Fermi level of the annealed ITO films at 400 °C, and the shift was reduced for temperatures higher than 400 °C. In addition, the results of curve-fitting for the core levels showed a change of ratios of SnO 2 and oxygen in the oxygen deficient regions after annealing. This is correlated to the change of carrier concentration and optical bandgap in the ultraviolet and near-infrared regions at different annealing temperatures.