A New Kind of Encapsulation Material for OLEDs
In this paper, we have introduced a new kind of encapsulation method consisting of an insulating layer Bi2S3 on top of Al cathode and cover glass. We have studied the performance of the device without Bi2S3 when the thicknesses of Alq3 are different and it has been deduced that the optimal thickness is 65 nm. Then we researched the performance of the passive matrix (PM) OLED whose structure is ITO/NPB(50 nm)/Alq3 (65 nm)/LiF(1 nm)/Al(100 nm)/Bi2S3 (x, x = 50 nm,75 nm,100 nm, 125 nm, 150 nm, 175 nm, 200 nm) prepared on an ITO coated glass by vacuum evaporation. From the experiment, it has been found that there is no crack or peel off on the surface of Bi2S3 film. Additionally, the Bi2S3 layer can improve the contrast of the device. When x equals 150 nm, the threshold voltage of the device is 2.81 V and the current density at a luminance of 100 cd/m2 was 0.90 mA/cm2. The luminance and voltage vary as a function of time at a constant current of 12 mA/cm2. The initial luminance of the device was 1 500 cd/m2, the luminance of Bi2S3 decreases by 24％ after 200hrs, and the driving voltage of the device increases from 5.41 V to 5.70 V.
Encapsulation Material Bi2S3 Insulating Layer
Fanghui Zhang Zhixian Li Xiufeng Wang
Department of Electric & Electron Engineering, Shaanxi University of Science & Technology, Xian, Ch Department of Material science & Engineering, Shaanxi University of Science & Technology, Xian, Chi
国际会议
上海
英文
392-395
2007-03-12（万方平台首次上网日期，不代表论文的发表时间）