功能层界面制备方法对OLED性能的影响

Effects of preparation method for functional layer interface on the performance of OLEDs

在功能层界面处采用各功能材料共蒸的方法,制备了典型的绿光有机发光器件(OLED)。器件的结构为ITO/NPB(37nm)/(NPB:Alq3)(3nm)/Alq3(27nm):C545T(3%)/Alq3(20nm)/LiF(1nm)/Al(100nm),并与传统的制备方法进行了比较。结果发现,起亮电压从4.5V降低到2.5V,最高耐压从16V提高到21V,最大亮度从13 940cd/m2提高到24 630cd/m2,发光效率由7.0cd/A提高到11.4cd/A。结果表明,本文方法有利于载流子传输,可以有效提高激子形成概率,提高了OLED发光效率。

In this paper, a typical green organic light-emitting device （OLED） was fabricated by using the common evaporate plating method on the interface layer in order to enhance the luminous efficiency and improve the I-V-L characteristics of OLED. The device structure is ITO/NPB（40 nm）/Alq3 （30 nm）： C545T（3%）/Alqa （20 nm）/LiF（1 nm）/Al（100 nm）. Compared with the typical method,it is found that the startup voltage is reduced from 4. 5 V to 2.5 V,and the highest withstand voltage is improved from 16 V to 21 V. The maximum brightness of the device is increased from 13 940 cd/m2 to 24 630 cd/m2 and the luminous efficiency rises to 11.4 cd/A from 7.0 cd/A. The results show that the common evaporate plating method is in favor of transmission to charge carriers. It can effectively improve the form probability of the excitons. It can enhance the luminous efficiency and improve the I-V-L characteristics of OLEDs.