Amorphous bilayer TiO₂-InGaZnO thin film transistors with low drive voltage

This paper describes a high-performance thin-film transistor (TFT) fabricated using TiO₂ and InGaZnO semiconducting layers. Favorable transistor characteristics, including a low threshold voltage of 0.45 V, a small subthreshold swing of 174 mV/decade, and a high field effect mobility of 19 cm²/V s at a low drive voltage of <2 V, were achieved. This favorable performance mainly resulted from the combined effect of the high-dielectric-constant gate dielectric and the TiO₂-InGaZnO active semiconductor bilayer, which reduced the operating voltage, enhanced the device mobility, and improved the transistor gate swing. This TiO₂-InGaZnO TFT exhibits great potential for future high-speed and high-resolution display applications.