Post-Annealing on the Electrical Properties of Ta-Doped In2O3 Transparent Conductive Films

Abstract

Ta-doped In2O3 transparent conductive oxide (TCO) films are deposited on glass substrates by radio-frequency (RF) sputtering at 300°C. The influence of post-annealing on the structural, morphologic, electrical, and optical properties of the films is investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Hall measurement, and optical transmission spectroscopy. The obtained films are polycrystalline with a cubic structure and preferentially oriented in the (222) crystallographic direction. The lowest resistivity of 5.1 × 10−4 Ω•cm is obtained from the film annealed at 500°C, which is only half of that from the un-annealed film (9.9 × 10-4 Ω).