发光学报, 2011, 32 (6): 576, 网络出版: 2011-06-24
红光颜色转换层调节的顶发射有机白光器件
Top-emitting White Organic Light-emitting Diodes with Red Color Conversion Layers
摘要
采用倒置结构顶发射蓝光器件和非掺杂型红光染料NPAMLI制备了TWOLED,研究了器件结构和光电性能的关系,器件结构为Glass/Al/Cs2CO3/Alq3/AND/NPB/MoO3/Au/Alq3/NPAMLI。NPAMLI的吸收谱与ADN的发光谱有较大的重叠,NPAMLI能够吸收ADN发出的部分蓝光并发射红光。实验中改变NPAMLI的厚度来调节器件发光颜色,当NPAMLI的厚度为300 nm时,器件的最高效率为1.25 cd/A (0.71 lm/W),发光色坐标为(0.330, 0.292)。
Abstract
Top-emitting white organic light-emitting diodes (TWOLEDs) have attracted intensive attention due to their great potential for high-resolution full color active matrix display and lighting applications. We have investigated optical and electrical characteristics of the TWOLED combining electroluminescence (EL) of blue material (ADN) with top color conversion layer (CCL) based on non-doped red material (NPAMLI). The TWOLED, with structure of Glass substrate/Al/Cs2CO3/Alq3/ADN/NPB/MoO3/Au/Alq3/NPAMLI, was fabricated by vacuum thermal evaporation. The 10 nm thick Au was used as top semitransparent anode, the 40 nm thick Alq3 was used as a capping layer to improve the light out-coupling, and the non-doped red material NPAMLI was used as the CCL. The NPAMLI CCL showed strong absorption from 450 nm to 550 nm, which matched well with the emission of the ADN. The EL spectra of the TWOLED additionally contained a red component from NPAMLI, which absorbed a part of the blue EL of the ADN, and converted this to its red fluorescence. Therefore, the TWOLED yielded a white light emission resulting from final mixture of color-converted red light and unabsorbed blue light. The TWOLED with a peak current (power) efficiency of 1.25 cd/A (0.71 lm/W), CIE coordinates of (0.330, 0.292), and a color rendering index of around 87.5, has been obtained.
陈双文, 王振, 周翔. 红光颜色转换层调节的顶发射有机白光器件[J]. 发光学报, 2011, 32(6): 576. CHEN Shuang-wen, WANG Zhen, ZHOU Xiang. Top-emitting White Organic Light-emitting Diodes with Red Color Conversion Layers[J]. Chinese Journal of Luminescence, 2011, 32(6): 576.