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http://dx.doi.org/10.12925/jkocs.2013.30.2.244

Effect of Changing the Thickness of Charge Control Layer on Performance of Green Phosphorescent Organic Light-Emitting Diodes  

Lee, Dong-Hyung (Dept. of Information Display, Hongik University)
Lee, Seok-Jae (Dept. of Information Display, Hongik University)
Koo, Ja-Ryong (Dept. of Information Display, Hongik University)
Lee, Ho-Won (Dept. of Information Display, Hongik University)
Lee, Song-Eun (Dept. of Information Display, Hongik University)
Yang, Hyung-Jin (Dept. of Information Display, Hongik University)
Park, Jae-Hoon (Dept. of Electronic Engineering, Hallym University)
Kim, Young-Kwan (Dept. of Information Display, Hongik University)
Publication Information
Journal of the Korean Applied Science and Technology / v.30, no.2, 2013 , pp. 244-250 More about this Journal
Abstract
We investigated green phosphorescent organic light-emitting diodes (PHOLEDs) with charge control layer (CCL) to produce high efficiency. The CCL and host material which was 4,4,N,N'-dicarbazolebiphenyl (CBP) of bipolar property can control the carrier movement in emitting layer (EML). The performance improvement by the insertion of CCL was realized to the well confined exciton and the reduced triplet exciton quenching effect in EML. Five types of devices (Device A, B, C, D, and E) were fabricated following the thickness of CCL within EML. The properties of device D using optimized thickness of CCL showed external quantum efficiency of 16.22% and luminous efficiency of 55.76 cd/A, respectively.
Keywords
green phosphorescent organic light-emitting diodes; charge control layer; triplet-triplet annihilation; bipolar;
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