Effect of thickness and substrate temperature on the properties of transparent Ti-doped In₂O₃ films grown by direct current magnetron sputtering

We reported on the effect of film thickness and substrate temperature on the properties of TiO₂-doped In₂O₃ (TIO) films deposited on a glass substrate by direct current (DC) magnetron sputtering for touch panel applications. The electrical, optical, surface and structural properties of TIO films grown at room temperature were significantly dependent on its thickness. At optimized TIO thickness (480 nm), the resistivity of the TIO film decreased with increasing substrate temperature due to effective activation of Ti dopant and crystallization of the In₂O₃ matrix. Furthermore, the increase in substrate temperature during DC sputtering leads to increase of optical bandgap of the TIO films due to Burstein–Moss effect, which is caused by change in carrier concentration of TIO films. At optimized conditions, the TIO film shows resistivity of 1.947 × 10⁻⁴ Ω-cm and optical transmittance of 85.3% comparable conventional indium tin oxide films. - Highlights: • Thickness effect on the properties of Ti-doped In₂O₃ (TIO) films was investigated. • TIO film properties were correlated with thickness and substrate temperature. • The optical band-gap of the TIO films due to Burstein–Moss effect was investigated