为了研究不同的空穴注入层修饰柔性衬底对柔性OLED器件性能的影响, 本文采用HAT-CN、PEDOT∶PSS、PEDOT∶PSS/HAT-CN 3种空穴注入层制备柔性OLED器件。设计的器件结构为PET/ITO/HIL/TAPC (60 nm)/CBP∶Ir(ppy)3 (20 nm, 10%)/TmPyPB (45 nm)/Liq (2 nm)/Al (100 nm)。采用旋涂的方法制备了PEDOT∶PSS, 其余有机层及阴极采用真空蒸镀法制备。结果表明, 采用PEDOT∶PSS/HAT-CN复合薄膜作为空穴注入层的柔性OLED器件性能最优。该器件的最大电流效率和最大功率效率分别为84 cd/A和76 lm/W。研究表明, 经PEDOT∶PSS修饰的柔性衬底表面更为连续及平滑, 不容易使器件发生漏电及短路现象; 同时PET/ITO/PEDOT∶PSS/HAT-CN复合薄膜在绿光波段有较高的透过率, 可以提高器件的出光率; 另外该双空穴注入结构使器件内部载流子的注入处于动态平衡状态, 增加了电子和空穴载流子的复合概率。

In order to study the effect of different hole injection layers on the performance of flexible OLED devices, HAT-CN, PEDOT∶PSS and PEDOT∶PSS/HAT-CN were used to prepare flexible OLED devices and measure their performance parameters. The device structure is PET/ITO/HIL/TAPC (60 nm)/CBP∶Ir(ppy)3 (20 nm, 10%)/TmPyPB (45 nm)/Liq (2 nm)/Al (100 nm). PEDOT∶PSS was prepared by spin coating, and the other organic layers and cathode were prepared by vacuum evaporation. The results show that the flexible OLED device with PEDOT∶PSS/HAT-CN composite film as hole injection layer has the best performance. The maximum current efficiency and power efficiency can reach 84 cd/A and 76 lm/W. The research shows that the surface of the flexible substrate modified by PEDOT∶PSS has better continuity and smoothness, so that the phenomenon of leakage and short circuit is reduced; meanwhile, the composite film of PET/ITO/PEDOT∶PSS/HAT-CN has a higher transmittance in green light band, which can improve the extraction efficiency of the device. Moreover, the injection of carriers in this device is in balance, increasing the compound probability of electrons and holes.