摘要
通过对器件结构的优化设计,提高了白光电致发光器件中蓝光成分的发光效率,从而得到了一种较为理想的有机白光电致发光器件。驱动电压为5V时,电流密度J=0 5mA/cm2,器件的效率达到最大,流明效率为1 92lm/W,此时器件的发光亮度接近20cd/m2,色坐标为(x=0 317,y=0 328),非常接近白光等能点,是色度很好的白光。并且在很大范围内,色度随器件的驱动电压或电流变化不大,当驱动电压变化至15V时,J=232mA/cm2,色坐标变化至(x=0 338,y=0 353)。在电压为22V时,器件的亮度达到最大,为17000cd/m2。此外器件结构相对简单,器件制备的可重复性得到很大程度的改善。
An organic whitelight electroluminescent device with high performances is designed and fabricated. In this work, the efficiency of bluelightemitting was improved only by designing the device structure, which increase the performances of the whitelightemitting device. Using a hole blocking material (BCP) to controlling the lightemitting zone based on NPB layer, we obtained bluelightemitting, which comes from excited NPB molecules. Similarly, we obtained yellowlightemitting by doping in NPB layer with rubrene. Base on the above, through partly doped NPB layer with rubrene, in which the doped part of NPB layer emits orangelight and the undoped part contributes to bluelight, we can obtain whitelightemitting. Because the undoped part of NPB is near the interface of NPB/BCP and this layer is very narrow, only about 3nm, the efficiency of bluelight emission is increased, which results the improvement of the performances of whitelight emitting device. The device has a maximum brightness of 17 000cd/m2 (at a driving voltage of 22V), and the maximum electroluminescent and power efficiency are 305cd/A and 192 lm/W (at a drive voltage of 5V, the current density of 05mA/cm2), respectively. At drive voltage of 5V, the CIE coordinate of the device is (x=0317, y=0328), which is very close to the equienergy point.
出处
《发光学报》
EI
CAS
CSCD
北大核心
2003年第3期270-274,共5页
Chinese Journal of Luminescence
基金
国家自然科学基金资助项目(60077014
59973007)
