具有新型双空穴注入层的有机发光二极管

A novel organic light-emitting diode by utilizing double hole injection layer

采用新型双空穴注入层N,N,N′,N′-tetrakis(4-Methoxy-phenyl)benzidine/Copper phthalocyanine(MeO-TPD/CuPc)及器件结构:ITO/MeO-TPD(15nm)/CuPc(15nm)/N,N′-Bis(naphthalen-1-yl)-N,N′-bis(phenyl)benzidine(NPB,15nm)/8-hydroxyquinoline(Alq3,50nm)/LiF(1nm)/Al(120nm),研制出高效有机发光二极管(器件D),与其他器件(器件A,没有空穴注入层的器件;器件B,MeO-TPD单空穴注入层;器件C,CuPc单空穴注入层)相比,其性能得到明显改善.器件D的起亮电压降至3.2V,比器件A,B,C的起亮电压分别降低了2,0.3,0.1V.器件D在10V时,其最大亮度为23893cd/m2,最大功率效率为1.91lm/W,与器件A,B,C的最大功率效率相比,分别提高了43%(1.34lm/W),22%(1.57lm/W),7%(1.79lm/W).性能改善的主要原因是由于空穴注入和传输性能得到了改善,通过单空穴型器件的J-V曲线对这一现象进行了分析.

Highly efficient organic light-emitting diode is fabricated with a novel double hole injection layer consisting of MeO-TPD/CuPc. We observe that the insertion of such a double hole injection layer leads to a striking enhancement in the electrical property： higher luminance, power efficiency and lower driving voltage. It has the configuration of ITO/MeO-TPD （15 nm）/CuPc（15 nm）/NPB（15 nm）/Alq 3 （50 nm）/LiF（1 nm）/Al（120 nm）. Its turn-on voltage is 3.2 V, which is 2, 0.3 and 0.1 V lower than those of the device without hole injection layer （device A） and the devices using MeO-TPD （device B）, CuPc （device C） as hole injection layer, respctively. The highest luminance of the novel device reaches 23893 cd/m^2 at a drving voltage of 10 V. The maximum power efficiency of the novel decive is 1.91 lm/W, which is 43% （1.34 lm/W）, 22% （1.57 lm/W） and 7% （1.79 lm/W） higher than those of devices A, B and C, respectively. The improvement is ascribed to its high hole injection and transport ability. The results are verified by using the J-V curves of ＂hole-only＂ devices.