针对目前大多数氧化物薄膜晶体管都需要采用热退火工艺来提高其性能不利于其在柔性显示器件中应用这一问题, 提出了一种采用室温工艺制备的新型TFT器件, 无需退火处理即可获得较好的器件性能。该器件采用脉冲激光沉积技术制备的AZO/Al2O3叠层结构作为沟道层。与单层AZO-TFT器件相比, 叠层TFT器件具有更优异的性能, 其迁移率为2.27 cm2·V-1·s-1, 开关比为1.43×106。通过对AZO/Al2O3叠层薄膜的厚度、密度、粗糙度、物相、界面特性及能带结构等进行分析, 发现这种叠层结构能够使电子的运动被限制在AZO薄膜平面内, 即形成了二维电子传输, 从而提升TFT器件的性能。

Most of the oxide thin film transistor (TFT) need thermal annealing process to improve its performance, which is detrimental to their applications in the flexible display devices. Concerning this problem, a new TFT structure with room temperature process was presented, which has good performance without annealing treatment. AZO/Al2O3 stacked thin film was prepared by pulsed laser deposition as a channel layer. The stacked TFT showed better performance than single-layer AZO-TFT. The field effect mobility and on/off current ratio were 2.27 cm2·V-1·s-1 and 1.43×106. By analyzing the thickness, density, roughness, phase and band structure of AZO/Al2O3 stacked thin film, it is found that the electrons can be confined in the potential well of AZO, which forms a two-dimensional electron transport to improve the performance of TFT device.