Effects of Gate Oxide Materials on the Electrical Performance of a Ga-Sn-O Thin Film Transistor

Effect of SiO2, La2O3, and TiO2 as the gate oxide on the electrical performance of Ga-Sn-O thin film transistor (GTO TFT) was investigated using ATLAS SILVACO®. The device was simulated in a 2D environment and the ratio of the on- to off-state currents (Ion/Ioff), subthreshold swing (SS), saturation current and gate capacitance were studies. The results showed that the TiO2/GTO TFT gives better electrical properties in terms of a larger Ion/Ioff, 2.73×1014, a smaller SS, 0.071 V/decade, a larger saturation current, 1.95×10-4 A, and a higher gate capacitance, 1.1×10-12 F/μm, compared to the La2O3/GTO and SiO2/GTO TFTs.

Keywords:

Ga-Sn-O (GTO) , thin-film transistor (TFT) , high-k , SiO2 , La2O3 , TiO2 , density of state model (DOS).