High-performance organic light emitting diodes fabricated with a ruthenium oxide hole injection layer

被引:21
作者
Kim, SY [1 ]
Lee, JL [1 ]
机构
[1] Pohang Univ Sci & Technol, Dept Mat Sci & Engn, Pohang 790784, Gyeongbuk, South Korea
关键词
OLED; hole injection layer; X-ray photoemission spectroscopy; O-2 plasma treatment; ruthenium oxide;
D O I
10.1007/BF03027512
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
We report enhanced hole injection using an RuOx layer between indium tin oxide anodes and 4,4'-bis[N-(1-naphtyl)-N-phenyl-amino]biphenyl in organic light emitting diodes (OLEDs). The operation voltage of OLEDs at a current density of 100 mA/cm(2) decreased from 17 V to 14 V and the maximum luminance value increased from 1200 cd/m(2) to 2500 cd/m(2) upon transformation of the Ru layer to RuOx by surface treatment using O-2 plasma. Synchrotron radiation photoelectron spectroscopy results showed that the work function increased by 0.4 eV as the Ru layer was transformed to RuOx. Thus, the hole injection energy barrier was lowered, reducing the turn-on voltage and increasing the quantum efficiency of the OLEDs.
引用
收藏
页码:411 / 414
页数:4
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