Investigation of Al- and Ag-Based Top-emitting Organic Light-emitting Diodes with Metal Oxides as Hole-injection Layer
Al- and Ag-based top-emitting organic light-emitting diodes (TOLED) are investigated. Both MoO3 and V2 O5 have been used as hole-injection layer (HIL). The performance of the devices is significantly improved using the metal oxides as HIL. A C545T-doped Alq3 TOLED with Al and MoO3 can achieve a maximum current efficiency of 22 cd/A at 20 mA/ cm2. The power efficiency is 20 lm/W at a low brightness and about 8. 9 1m/W at 1 000 cd/m2. For the Ag-based TOLED using V2 O5 as HIL, very low operating voltages are obtained. For instance, 1 000 cd/m2 can be obtained at a voltage of 4.7 V with a power efficiency of about 10 lm/W. From the analysis of the current-voltage characteristics of the single-hole transport layer devices, it is believed that the hole injection from the metal anodes was greatly enhanced because of the lowering of the injection barrier induced by the metal oxides.
TOLED HIL Metal Oxide
X. L. Zhu J. X. Sun X. M. Yu M. Wong H. S. Kwok
Center for Display Research and Dept. of Electronic and Computer Engineering,The Hong Kong University of Science and Technology, Clear Water Bay,Kowloon, Hong Kong, China
国际会议
上海
英文
1429-1433
2007-03-12(万方平台首次上网日期,不代表论文的发表时间)