State Key Laboratory of Luminescence and Applications, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, People's Republic of China. University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
Nanotechnology. 2017 Sep 8;28(36):365201. doi: 10.1088/1361-6528/aa7d9c. Epub 2017 Jul 4.
As an indium-free transparent conducting film, Al-doped zinc oxide (AZO) was prepared by magnetron sputtering technique, exhibiting good electrical, optical and surface characteristics. UPS/XPS measurements show that AZO and zinc oxide nanoparticles (ZnO NPs) have matched energy level that can facilitate the electron injection from AZO to ZnO NPs. Inverted structural green quantum dot light-emitting diodes based on AZO cathode were fabricated, which exhibits a maximum luminance up to 178 000 cd m, and a maximum current efficiency of 10.1 cd A. Therewith, combined with the simulated space-charge-limited current (SCLC) theory, the measured current density-voltage characteristics of charge-only devices were analyzed. It demonstrated that AZO and ZnO NPs had much better electron injection efficiency than ITO, showing a electron injection efficiency close to 100%. By studying the relationship between the electric field and the current density, the measured curve of AZO-based devices nearly fits the theoretical curve of SCLC and the AZO electrode has a better ohmic contact with ZnO NPs than ITO.
作为一种无铟透明导电膜，掺铝氧化锌（AZO）采用磁控溅射技术制备，表现出良好的电学、光学和表面特性。UPS/XPS 测量表明，AZO 和氧化锌纳米粒子（ZnO NPs）具有匹配的能级，这有利于电子从 AZO 注入 ZnO NPs。基于 AZO 阴极的倒置结构绿色量子点发光二极管被制备，其展示了高达 178000 cd m 的最大亮度和 10.1 cd A 的最大电流效率。此外，结合模拟空间电荷限制电流（SCLC）理论，对电荷控制器件的测量电流密度-电压特性进行了分析。结果表明，AZO 和 ZnO NPs 的电子注入效率远优于 ITO，接近 100%。通过研究电场与电流密度的关系，AZO 基器件的测量曲线几乎符合 SCLC 的理论曲线，并且 AZO 电极与 ZnO NPs 的欧姆接触优于 ITO。
