溶液法制备氧化锌半导体薄膜及其顶栅极晶体管器件

采用旋涂法用浓度分别为0.05，0.10和0.25 mol·L^-1的氧化锌前躯体溶液制备了氧化锌薄膜，并且制备了基于氧化锌多层膜的顶栅极晶体管器件，其中以利用光刻工艺刻蚀的氧化铟锡为源漏电极。通过原子力显微镜(AFM)和X-射线衍射(XRD)分别表征了薄膜的形貌以及结晶情况，并且讨论了前躯体的浓度顺序对氧化锌多层膜的影响。按照浓度从大到小的顺序依次旋涂前躯体溶液制备的氧化锌薄膜表现出了较高的载流子迁移率(7.1×10^-3 cm²·V^-1·s^-1)，而按照浓度从小到大的顺序依次旋涂前躯体溶液制备的氧化锌薄膜的载流子迁移率为5.2×10^-3 cm²·V^-1·s^-1。文中通过对两种多层薄膜的形貌和结晶性能的分析表明影响顶栅极薄膜晶体管性能的主要因素是薄膜的粗糙度。平整的薄膜有利于形成较好的半导体层/绝缘层接触界面，从而有利于提高器件的载流子迁移率。

Solution-Processed Zinc Oxide Thin Films and Top-Gate Thin Film Transistors

ZnO thin films were prepared by spin-coating the precursor solution with different concentrations. The morphologies and crystallinity of the ZnO films were characterized by Atomic Force Microscopy (AFM) and X-ray Diffraction (XRD). Multilayer ZnO films were employed as active layers to prepare thin film transistors (TFTs), and patterned indium tin oxide (ITO) was used as source and drain electrodes. The device based on the three-layer ZnO films, prepared with the precursor concentration order of 0.25, 0.10 and 0.05 mol·L^-1, showed higher mobility of 7.1×10^-3 cm²·V^-1·s^-1 than the device with the precursor concentration order of 0.05, 0.10 and 0.25 mol·L^-1 (5.2×10^-3 cm²·V^-1·s^-1). The difference of the performance of TFTs based on these two kinds of films is attributed to the roughness of the multilayer ZnO thin films. Smooth film is useful for forming excellent semiconductor/insulator interface, resulting in high mobility.