IGZO薄膜溅射功率对IGZOTFT栅电压不稳定性的影响

Gate bias stress induced instability of InGaZnO thin film transistor under different sputter power

采用不同溅射功率制备的铟镓氧化锌(IGZO)薄膜作为薄膜晶体管(TFT)的有源层,通过扫描电镜、霍尔效应测试仪,分析了溅射功率对IGZO薄膜形貌及电特性的影响,研究了不同IGZO溅射功率对IGZO-TFT栅偏压不稳定性的影响。结果表明,在一定范围内,低溅射功率使得IGZO薄膜的表面粗糙,缺陷较多,载流子浓度较低;在正栅极偏压作用下,低IGZO薄膜溅射功率导致较大的IGZO-TFT阈值电压漂移;在负偏压作用下不产生阈值电压漂移。

IGZO film,as the active layer of thin film transistor,is prepared by different sputter power.The film morphology and the electrical characteristics of IGZO film are measured by scanning electron microscopy and Hall effect measurement system.The instability of IGZO TFT prepared by different sputter power under gate bias stress is studied.The result shows that,in a certain range,the film prepared by lower sputter power has rough surface,more defect density and lower carrier concentration.Positive gate bias induces IGZO-TFT positive voltage threshold shift,but negative gate bias stress do not produce voltage threshold shift.