Summary: | 碩士 === 國立雲林科技大學 === 電子與光電工程研究所碩士班 === 101 === This work has investigated on high-efficiency white organic light-emitting diodes (WOLEDs). First, we have compared the non-doped, conventionally doped, and multilayer-doped structures for the WOLEDs. Our results show that the multilayer-doped structure has better emission performance than the other structures. The quantized energy bands of the multilayer-doped emitting layer facilitate the electron and hole carriers to recombine in balance so that the emission properties of the WOLED can be improved. Both the emission efficiency and color stability are increased with effective energy transfer in the multilayer-doped emitting structure. In this work, the optimum WOLED structure with multilayer-doped emission layer is ITO/NPB(50nm)/{MADN(5nm)+[MADN:0.33%TBRb(6.25nm)]*8+MADN(5nm)}/Alq3(15nm)/LiF(1nm)/Al(120nm). When the doping concentration is 0.33%, it can effectively balance the intensity of blue and yellow light, and obtain the CIE coordinates of (0.33, 0.38) with a maximum luminance of 10400 cd/m2 and a maximum current efficiency of 6.13 cd/A.
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