利用LiF/Al作为电极的有机电致发光器件

FABRICATION OF ORGANIC LIGHT-EMITTING DEVICES USING LiF/Al AS CATHODE

本文报道了利用 L i F/ Al作为负电极的有机电致发光器件 ,器件结构为 ITO/ TPD/Alq3/ Li F/ Al,Li F层的加入增强了电子注入 ,当其厚度为 0 .4nm时 ,器件的性能最好 ,与单层 Al和 Mg/ Al电极的同类器件相比 ,此时器件的开启电压由 Al电极时的 4.3V和 Mg/ Al电极时的 3.0 V降低到了 2 .0 V,器件的最大亮度分别由 40 0 0 cd/ m2、1 40 0 0 cd/ m2提高到1 960 0 cd/ m2 ,器件的发光效率也分别增加了 5倍和 2倍 ,达到 2 .66lm/ W.

It is reported the fabrication of organic light emitting devices (OLEDs) using LiF/Al as cathode.The structure of this devices is ITO/TPD/Alq 3/LiF/Al,and the insertion of the ultra thin LiF layer enhanced the electron injection in this device.As a result,when the thickness of the LiF layer is optimized 0.4nm,the OLEDs′properties show best,its maximum brightness is 19600 cd/m 2(17V),while the devices with Al cathode or Mg/Al cathode exihibit only 4000 cd/m 2(22V),14000 cd/m 2(19V) respectively.And the operating voltage for devices with LiF/Al cathode is lower (2.0V) than those of devices with Al cathode (4.3V) or Mg/Al cathode (3.0V).Its luminescent efficiency is 5 and 2 times than that of devices with Al cathode or Mg/Al cathode.