In this paper, amorphous InGaZnO 4 thin-film transistors with an asymmetric structure exhibit ultraviolet (UV) light sensing property. At the offset region near the drain electrode, the extended active layer plays the role of a resistor. However, the ON-state current is obviously reduced with increasing offset length at the offset region near the source electrode and the characteristics cannot be turned ON when offset length is over 4 μ m. After exposure to UV light, photogenerated holes-induce source barrier lowering and then amplifying the photocurrent response. Therefore, the devices in this paper reach a high-ON/OFF ratio of UV sensitivity to (10 6 .
- Amorphous InGaZnO (a-InGaZnO)
- thin-film transistors (TFTs)
- ultraviolet (UV) sensor