溶液法制备氧化铝介质层的非晶铟锌氧化物薄膜晶体管

IZO Thin-film Transistors with Solution Processed Alumina Gate Dielectric Layer

采用旋涂法制备了氧化铝栅介质层薄膜.通过XRD和AFM分析表征了薄膜的结晶性和表面平整性.分光光度计测试表明薄膜在可见光范围的平均透射率大于85%.采用MIM结构研究其漏电流密度,在电场强度为1MV/cm时仅为3×10-9 A/cm2,表明可以用作栅介质层.以旋涂法涂覆的a-IZO薄膜为沟道层、旋涂法涂覆的氧化铝为介质层,制备了底栅结构的氧化物薄膜晶体管.测试表明该薄膜晶体管工作在n型沟道增强型模式,器件场效应迁移率为1.4cm2/(V·s),电流开关比约为105,阈值电压为2.2V,显示出相对较好的器件性能.

The alumina gate dielectric layer has been prepared by spin coating method. The crystallinity and surface mophology were examined by XRD and AFM. The average transmission in the visible region of the film is more than 85%. Through the MIM structure the leakage current density of the film is 3 × 10 ^-9 A/cm2 at 1 MV/cm, which suggest that the layer is suit for the gate dielectric. The bottom-gate IZO thin film transistors with alumina gate-insulator was fabricated. Measurement reveals that the oxide-TFTs operate in n-type enhancement mode with a field-effect mobility of 1.4 cm2/（V · s）, an on-off current ratio of l0s , threshold voltage of 2.2 V, showing the relative good performance.