Xi Jian-Fei, Zhang Fang-Hui, Mu Qiang, Zhang Mai-Li
Shaanxi Engineering Center for Display Devices, Xi'an 710021, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2011 Sep;31(9):2337-40.
It is demonstrated that the panchromatic luminescence devices with organic blue-emissive light-emitting was fabricated. This technique used down conversion, which was already popular in inorganic power LEDs to obtain white light emission. A blue OLED device with a configuration of ITO/2T-NATA (30 nm)/AND : TBPe (50 Wt%, 40 nm)/Alq3 (100 nm)/LiF(1 nm)/Al(100 nm) was prepared via vacuum deposition process, and then coated with YAG : Ce phosphor layers of different thicknesses to obtain a controllable and uniform shape while the CIE coordinates were fine tuned. This development not only decreased steps of technics and degree of difficulty, but also applied the mature technology of phosphor. The results showed that steady spectrogram was obtained in the devices with phosphor, with a best performance of a maximum luminance of 13 840 cd x m(-2) which was about 2 times of that of the devices without phosphor; a maximum current efficiency of 17.3 cd x A(-1) was increased more two times more than the devices without phosphor. The emission spectrum could be adjusted by varying the concentration and thickness of the phosphor layers. Absoulte spectrogram of devices was in direct proportion with different driving current corresponding.
结果表明，制备了具有有机蓝色发光的全色发光器件。该技术采用了下转换，这在无机功率发光二极管中已经很常见，以获得白光发射。通过真空沉积工艺制备了结构为ITO/2T-NATA（30nm）/AND:TBPe（50wt%，40nm）/Alq3（100nm）/LiF（1nm）/Al（100nm）的蓝色OLED器件，然后涂覆不同厚度的YAG:Ce磷光体层，以获得可控且均匀的形状，同时对CIE坐标进行微调。这一进展不仅减少了工艺步骤和难度，还应用了成熟的磷光体技术。结果表明，含磷光体的器件获得了稳定的光谱图，最佳性能为最大亮度13840cd·m⁻²，约为不含磷光体器件的2倍；最大电流效率为17.3cd·A⁻¹，比不含磷光体的器件提高了两倍多。发射光谱可通过改变磷光体层的浓度和厚度来调节。器件的绝对光谱图与不同的驱动电流成正比。
