Achieving High Field-Effect Mobility Exceeding 50 cm \(^{\mathrm {2}}\) /Vs in In-Zn-Sn-O Thin-Film Transistors

Bottom gate and etch stopper-type thin-film transistors (TFTs) with a channel layer of indium-zinc-tin oxide were fabricated. The resulting TFTs exhibited a high mobility exceeding 52 cm
²
/Vs, a low subthreshold gate swing of 0.2 V/decade, a threshold voltage of 0.1 V, and an I
_ON/OFF
ratio of >2 × 10
⁸
. The stability of the oxide passivated device under the positive and negative bias stress conditions was superior to that of the nitride passivated device, which can be attributed to the lower trap density in the channel layer.