关键词: 薄膜晶体管, 氧化锌, 光诱导, 稳定性

Abstract:

 In order to promote the commercial application of ZnO- based thin film transistors (ZnO- TFTs) to active-driving flat display field,TFTs with ZnO as the channel layer were fabricated via the RF (Radio Frequency) mag-netron sputtering with undoped ZnO target.Then,the photo- induced instability of the devices was investigated under visible light illumination.Experimental results indicate that (1) the ZnO- TFT device exhibits light- induced instability under visible light illumination; (2) with the increase of illumination intensity,the carrier mobility of the device slightly increases,while the threshold voltage weakly reduces; and (3) the relative variation of drain current is strongly modulated by gate voltage,for instance,it becomes smaller with a minimum of 0.58 at 2210lx when the device operates in the on- state mode,but becomes larger with a maximum of 36.29 at the same illumina-tion intensity when the device operates in the subthreshold or off- state mode.Moreover,it is also found that,the recovery of the photo- induced instability is relatively slow and tends to slow down with the passage of time.

Key words:  thin film transistors, zinc oxide, photoinduction, stability