Improved IGZO-TFT structure Using High-k Gate Dielectric Materials

In this paper an IGZO-TFT based on High-K gate dielectric is simulated using TCAD software. We report on the electrical properties of amorphous indium-gallium-zinc-oxide thin-film transistors (TFTs) with a range of oxides (SiO2, HfO2, ZrO2, Al2O3or TiO2) gate dielectrics materials IGZO-TFT with TiO2layer dielectric exhibited threshold voltage Vthof 2 V, a Saturation mobility μsatof 4.51 cm2/Vs, Subthreshold swing SS of 0.075 V/dec, and a current ratio Ion/Ioffof 1.244E13. These characteristics make it suitable for use as a switching transistor in low-power application, furthermore a temperature-dependent transfer characteristic of the a-IGZO TFT, ranging from 300 to 500 k. show that more the dielectric constant of the oxide gate dielectric is high, more we get a high current.