DocumentCode :
2697569
Title :
Highly efficient organic light-emitting devices
Author :
Liu, Shiyong ; Li, Feng ; Cheng, Gang ; Feng, Jing
Author_Institution :
Nat. Lab of Integrated Optoelectronics, Jilin Univ., Changchun, China
fYear :
2003
fDate :
12-14 Sept. 2003
Firstpage :
266
Lastpage :
269
Abstract :
For organic light-emitting devices (OLEDs), improving efficiency is very important. Many scientists are interested in it. In this paper, we report some of our results. The optical and electrical characteristics of organic red light-emitting devices are improved through utilizing the two-step energy transfer, the maximum efficiency is 2.9 cd/A. The efficiency of white organic light-emitting devices has been improved dramatically by the introduction of phosphorescent material fac tris (2-phenylpyridine) indium [Ir(ppy)3] as sensitizer. The maximum efficiency is 6.0 cd/A. Two kinds of new phosphorescent materials (s-phen)Re(CO)3Cl (s-phen = 3,9-dimethyl-1,10-phenanthroline) and (s-bpy) Re(CO)3Cl (s-bpy = 4,4´dimethyl formate-2,2´-bipyridine) are employed to fabricate the organic electrophosphorescence devices. The maximum efficiencies and the light colors of the devices based on (s-phen)Re(CO)3Cl and (s-bpy) Re(CO)3Cl are 7.15 cd/A, yellow and 1.28 cd/A, orange-red, respectively. The devices with two rubrene sub-monolayers are fabricated. The maximum electroluminescent efficiency of the device was 6.61 cd /A at 7 V. It was higher than the common dope-type device, and besides, the efficiency is relatively independent on the drive voltage in the range from 5 to 13 V. The brightness can reach 18610 cd/m2 at 13 V.
Keywords :
brightness; electroluminescence; organic light emitting diodes; organic semiconductors; (s-bpy) Re(CO)3Cl; (s-phen)Re(CO)3Cl; 3,9-dimethyl-l,10-phenanthroline; 4,4´- dimethyl formate-2,2´-bipyridine; 5 to 13 V; OLED; brightness; electroluminescent efficiency; organic electrophosphorescence devices; organic light-emitting devices; organic red light-emitting devices; phosphorescent material; rubrene submonolayers; tris (2-phenylpyridine) indium [Ir(ppy)3]; two-step energy transfer; Electric variables; Electroluminescent devices; Energy exchange; Indium; Optical devices; Optical materials; Optical sensors; Organic light emitting diodes; Organic materials; Phosphorescence;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Optoelectronics, Proceedings of the Sixth Chinese Symposium
Print_ISBN :
0-7803-7887-3
Type :
conf
DOI :
10.1109/COS.2003.1278220
Filename :
1278220
Link To Document :
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