Effect of oxygen defect on the performance of Nd: InZnO high mobility thin-film transistors

High mobility and stability are eternal themes for oxide semiconductor TFT. However, there is a natural contradiction between mobility and stability. The oxygen defect state has a great influence on oxide semi-conductor devices, so we adopt different sputtering oxygen percentages to prepare Nd: InZnO films of different deposition states. The type and number of oxygen defects were extracted and fitted by mu-PCD, XPS, and CV. Through a series of characterization tests on thin films and devices, the influence mechanism of oxygen-related defect states on the performance and instability of high mobility oxide TFT was analyzed. The results show that the stability of TFT can be improved by appropriately increasing the oxygen percentage, but some mobility will be lost. Finally, we have achieved devices with high mobility and good stability by cleverly designing homo-junction TFT. The best device performance is mu sat=38.2 cm(2)V-1S(-1), SS= 0.13 V/dec, Vth & AP; 0 V, Ion/off=4.3 x 108. This is a simple and effective way to prepare high-performance TFT circuits.

Automated summary

In this study, the influence mechanism of oxygen-related defect states on the performance and stability of high mobility oxide TFT was analyzed by adjusting the oxygen percentage. Through the clever design of homo-junction TFT, devices with high mobility and good stability were achieved.