Design of Highly Stable Tungsten-Doped IZO Thin-Film Transistors With Enhanced Performance

High-performance thin-film transistors (TFTs) were obtained by incorporating small amount of tungsten (W) into amorphous indium zinc oxide (IZO)-based thin films via a solution process. Compared with original IZO TFTs, 0.2-wt% W-doped IZO TFTs exhibit improved bias stress stability and field-effect mobility of 30.5 cm
²
/V·s. Meanwhile, the bias stress stability of IZO TFTs can be further enhanced with 0.5-wt% W-doping. The pulsed current-voltage (I-V) method is employed to study the hysteresis and charging behavior of the W-doped IZO TFTs. The X-ray photoelectron spectroscopy analysis and the pulsed I-V measurement results suggest that these desirable performances could be attributed to the suppression of excessive oxygen vacancies and improved interface quality because of W-doping. The results represent an effective strategy to achieve high-performance solution-processed amorphous oxide-based TFTs with desirable stability by W-doping.