摘要：
For the purpose of improving the performance of organic light-emitting device (OLED), the green phosphorescent OLED was fabricated using Ir(ppy)3as emitter and CsN3as N-dopant doped in B3PYPPM which functioned as electron-transporting layer (ETL). The N-doped device with best performance named device B comprising ITO/HAT-CN(5 nm)/TAPC(70 nm)/TCTA:Ir(ppy)3(15%,20 nm)/B3PYPPM(17 nm)/B3PYPPM:CsN3(10%,63 nm)/Al was achieved by optimizing the doping concentration and the thickness of N-doped ETL. The results indicate that employing the N-doped ETL possessing proper doping concentration as well as thickness can enhance current efficiency and power efficiency dramatically. Served effectively as N-dopant in B3PYPPM, CsN3reduces the injection barrier for electron, enhances the electron conductivity, facilitates the electron injection and transportation and enhances the charge balance, leading to the decrease in turn on and operating voltages as well as improvement on current efficiency and power efficiency. The optimized N-doped device B shows rather low turn-on voltage with the value of 2.1 V,and the maximum efficiencies are 67.0 cd/A and 91.1 lm/W respectively. It is worthwhile to point out pow-er efficiency of device B can also reach 80.1 lm/W at high luminance of 1 000 cd/m2.%为了改善有机电致发光器件的性能,利用CsN3作为N掺杂剂,以B3PYPPM为电子传输材料,制备了基于绿色磷光材料Ir(ppy)3的高效率有机电致发光器件.针对不同N掺杂浓度和掺杂厚度的器件进行研究,最终得到最佳N掺杂器件B,器件结构为ITO/HAT-CN(5 nm)/TAPC(70 nm)/TCTA:Ir(ppy)3(15%,20 nm)/B3PYPPM(17 nm)/B3PYPPM:CsN3(10%,63 nm)/Al.实验结果表明,浓度与厚度适当的N掺杂器件能有效提高器件的电流效率和功率效率.CsN3作为一种高效的N掺杂剂,与电子传输材料B3PYPPM掺杂后,有效地降低了电子的注入势垒,增加了电子注入,提高了电子迁移率,改善了电子的注入和传输能力,使载流子更加平衡,从而降低了器件的开启电压和驱动电压,有效地提高了电流效率和功率效率.最佳N掺杂器件B开启电压仅为2.1 V,最大电流效率和功率效率分别为67.0 cd/A、91.1 lm/W.值得注意的是,在1000 cd/m2亮度下,最佳N掺杂器件B的功率效率仍能达到80.1 lm/W.
