Effect of Zr Addition on Sol-Gel Processed InZrZnO Thin-Film Transistor

In this study, solution-processed InZrZnO thin films and a newly developed thin-film transistors (TFTs) were fabricated and characterized electrically. The InZrZnO TFTs were investigated according to the variation of the Zr-metal doping concentration. It was found that the off currents of InZrZnO TFTs were greatly influenced by the composition of Zr atoms suppressing formation of oxygen vacancies. The optimal transistor of InZrZnO channel layer shows good performance properties. The electrical characteristics of a 2.92 mol% Zr-doped InZnO TFT shows a field effect mobility of 0.05 cm2 V−1 s−1, a threshold voltage of 6.1 V, an on/off ratio of 1.4 × 107, and a subthreshold swing of 0.42 V/dec. The InZrZnO TFT also shows better bias stability than undoped InZnO TFT, suggesting Zr plays a key role in regards to stability of TFT.