双栅非晶InGaZnO 薄膜晶体管( DG a-IGZO TFTs) 具有比单栅a-IGZO TFTs 更优良的电学性能． 文中基于a-IGZO/SiO₂界面缺陷态呈指数型分布的模型，讨论了在界面缺陷态影响下双栅驱动的DG a-IGZO TFTs 有源层厚度对电学性能的影响． 研究结果表明:随着有源层厚度的减小，双栅驱动模式下DG a-IGZO TFTs 两栅极的耦合作用增强，有源层上、下表面的导电沟道向体内延伸，使器件的场效应迁移率显著增加; 界面缺陷态对DG a-IGZO TFTs 场效应迁移率的影响随着有源层厚度的减小而降低，对亚阈值摆幅的影响随着有源层厚度的减小而增大．

Dual-gate amorphous InGaZnO thin film transistors ( DG a-IGZO TFTs) have better electrical characteristics than single-gate a-IGZO TFTs.In this paper,on the basis of a model describing the exponential distribution of defect states of a-IGZO/SiO₂ interface,the effects of the active layer thickness of DG a-IGZO TFTs on their electrical characteristics are investigated by taking into consideration the interface defect states.The results show that,as the active layer becomes thinner,the two gates of DG a-IGZO TFTs get coupled more strongly,which causes the conduction channels initially locating at the front and back interfaces of active layer to extend into the bulk of a-IGZO,thus greatly increasing the field effect mobility of DG a-IGZO TFTs.In addition,with the decrease of the active layer thickness,the field effect mobility of DG a-IGZO TFTs gradually becomes immune to the interface defect states,while the subthreshold swing becomes more sensitive to the interface defect states.