Impact of Source/Drain Metal Work Function on the Electrical Characteristics of Anatase TiO₂-Based Thin Film Transistors

Abstract

Thin film transistors (TFTs) with anatase-TiO2 channel material deposited on an SiO2/Si substrate by atomic layer deposition are fabricated to investigate the effect of the source/drain (S/D) metal work function on the electrical characteristics of the TFTs. S/D materials such as aluminum, silver, and gold are selected for this study. From the measured current-voltage characteristic curves in the dark and at room temperature, it is demonstrated that the anatase TiO2-based TFT with Ag S/D material shows the highest on/off-current ratio (∼ 105), field effect mobility in the saturation regime (μsat = 5.17 cm2V−1s−1), and saturation current (IDS,sat ∼ 0.47 mA).