High mobility transparent flexible nickel-doped zinc oxide thin-film transistors with small subthreshold swing

High-mobility nickel (Ni)-doped zinc oxide thin-film transistors (NZO TFTs) have been successfully fabricated on flexible transparent plastic substrates at a low temperature. The devices all exhibited good electrical properties with small subthreshold swing (SS) and high saturation mobility fabricated under different sputtering pressure (0.4, 0.8, 1.2, 1.6 Pa) during channel deposition by RF magnetron sputtering were found. The electrical properties of NZO TFTs reached the best when the sputtering pressure was 1.6 Pa, with an SS of 89 mV/decade, a saturation mobility of 172 cm²·V^-1·s^-1, a drain current on/off ratio of 10⁸, and a positive threshold voltage of 2.36 V. The results show that Ni-doped ZnO is a promising candidate for flexible fully transparent displays.