低温透明非晶IGZO薄膜晶体管的光照稳定性

采用室温射频磁控溅射非晶铟镓锌氧化合物(a-IGZO), 在相对低的温度(<200 ℃)下成功制备底栅a-IGZO 薄膜晶体管器件, 其场效应迁移率10 cm^-2·V^-1·s^-1, 开关比大于10⁷, 亚阈值摆幅 SS为0.4 V/dec, 阈值电压为3.6 V. 栅电压正向和负向扫描未发现电滞现象. 白光发光二极管光照对器件的输出特性基本没有影响, 表明制备的器件可用于透明显示器件. 研究了器件的光照稳定性, 光照10000 s后器件阈值电压负向偏移约0.8 V, 这种漂移是由于界面电荷束缚所致. 关键词： 非晶铟镓锌氧化合物 薄膜晶体管 光照稳定性 电滞现象

Stability of low temperature and transparent amorphous InGaZnO thin film transistor under illumination

The amorphous indium-gallium-zinc-oxide (a-IGZO) thin films are prepared by radio frequency magnetron sputtering at ambient temperature. The transparent thin film transistors (TFT) fabricated at low temperature (<200 ℃) with a-IGZO active channel exhibits good electrical properties with a field effect mobility of around 10 cm²·V^-1·s^-1, subthreshold swing of 0.4 V/decade, and high Ionoff current ratio of over 10⁷. Hysteresis is not observed when gate voltage sweeps forward and reverses. And the dependence of white LED illumination on characteristic of a-IGZO TFT is investigated. The results show that output characteristic is hardly affected, indicating the potential of the devices for transparent electronics In particular, illumination stability is investigated under white LED illumination stress test, and the a-IGZO TFT shows only 04 V shift in threshold voltage. The negative shift can be explained on the basis of trap of interface state.
Keywords： amorphous indium-gallium-zinc-oxide thin film transistors illumination stability hysteresis