Title :
Very efficient high-luminance electrophosphorescent emission in polymer light-emitting diodes
Author :
Xie, Zhiliano ; Qiu, Chengfeng ; Chen, Haiying ; Peng, Huajun ; Wong, Man ; Tang, Benjamin Z. ; Kwok, Hoi Sing
Author_Institution :
Center for Display Res., Hong Kong Univ. of Sci. & Technol., Kowloon, China
Abstract :
The electrophosphorescent emission properties were investigated in polymer light-emitting diodes (PLEDs) based on a poly(9-vinylcarbazole) (PVK) doped with a green phosphorescent dye of fac-tris(2-phenylpyridine) iridium (III) [Ir(ppy)3]. A green light peaked at 516 nm was emitted from devices with a configuration of ITO/PEDOT:PSS/PVK:Ir(ppy)3/BCP/Alq3/LiF/Al. The optimal doping concentration of Ir(ppy)3 in PVK was found at 2% by weight, under which maximum current efficiency of 24.3 cd/A and peak external quantum efficiency of 6.8% were achieved at the high luminance of 4240 cd/m2. The external quantum efficiency of 5% and current efficiency of 18 cd/A can be sustained even at the very high luminance of 35000 cd/m2.
Keywords :
brightness; doping profiles; dyes; electroluminescence; optical polymers; organic light emitting diodes; organic semiconductors; semiconductor device testing; visible spectra; 6.8 percent; current efficiency; electrophosphorescent emission; fac-tris(2-phenylpyridine) iridium (III); green phosphorescent dye; luminance; optimal doping concentration; poly(9-vinylcarbazole); polymer light-emitting diodes; quantum efficiency; Charge carrier processes; Chemistry; Displays; Doping; Excitons; Glass; Indium tin oxide; Light emitting diodes; Organic light emitting diodes; Phosphorescence;
Conference_Titel :
Optoelectronics, Proceedings of the Sixth Chinese Symposium
Print_ISBN :
0-7803-7887-3
DOI :
10.1109/COS.2003.1278198
