Influence of doping profile on the efficiency of blue phosphorescent organic light-emitting diodes

被引：65

作者：

Lee, Jonghee ^{[1
]}

Lee, Jeong-Ik ^{[1
]}

Song, Ki-Im ^{[1
]}

Lee, Su Jin ^{[1
]}

Chu, Hye Yong ^{[1
]}

机构：

[1] Elect & Telecommun Res Inst, IT Convergence & Components Lab, Taejon 305350, South Korea

来源：

APPLIED PHYSICS LETTERS | 2008年 / 92卷 / 13期

关键词：

D O I：

10.1063/1.2904632

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We demonstrate that electroluminescent efficiency of blue phosphorescent organic light-emitting diodes could be improved by changing doping profile in the emissive layer (EML) of the device containing iridium(III)bis(4,6-difluorophenyl)-pyridinato-N,C-2') picolinate (FIrpic) and N,N'-dicarbazolyl-3,5-benzene (mCP). By examining the changes of recombination zone and current density with a partially doped EML, we found that most of the recombination occurred at the EML close to the electron transporting layer (ETL). Electron injection and transport were enhanced by increasing doping ratio at the EML close to the ETL and such a stepwise doping profile resulted in almost 40 % improved power efficiency compared to that of a conventional device. (C) 2008 American Institute of Physics.

引用

页数：3

共 21 条

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