This letter studies the correlation of postannealing treatment on the electrical performance of amorphous In-Zn-Sn-O thin-film transistor (a-IZTO TFT). The 400 °C annealed a-IZTO TFT exhibits a superior performance with field-effect mobility of 39.6 cm2/Vs, threshold voltage (Vth) of -2.8 V, and subthreshold swing of 0.25 V/decade. Owing to the structural relaxation by 400 °C annealing, both trap states of a-IZTO film and the interface trap states at the a-IZTO/SiO2 interface decrease to 2.16 × 1017 cm-3 eV-1 and 4.38 × 1012 cm-2 eV-1, respectively. The positive bias stability of 400 °C annealed a-IZTO TFTs is also effectively improved with a Vth shift of 0.92 V.
- high mobility TFTs
- In-Zn-Sn-O TFTs