The Investigation of Two Different Types of Multiple-Quantum-Well Structure on Fluorescent White Organic Light Emitting Devices

Chen, YuC; Fang, YC; Wu, MHua; Juang, YDer; Chu, SY

HERO ID

3576188

Reference Type

Journal Article

Year

2012

HERO ID 3576188
In Press No
Year 2012
Title The Investigation of Two Different Types of Multiple-Quantum-Well Structure on Fluorescent White Organic Light Emitting Devices
Authors Chen, YuC; Fang, YC; Wu, MHua; Juang, YDer; Chu, SY
Volume 1
Issue 2
Page Numbers R66-R71
Abstract To study the effect of multiple-quantum-well (MQW) structure on emission characteristics of white organic light-emitting diodes (WOLEDs), we fabricate trapping-type and blocking-type MQWs by inserting C545T (green dye) and TPBi, respectively, into hole transport NPB layer (ITO/CuPc/NPB/MADN:rubrene/TPBi/LiF/Al). Bright efficient and stable fluorescent white emission was obtained for the OLED with 2 trapping-type MQWs formed with C545T (thickness: 2 nm). The device current and power efficiency were greatly raised 36% (7.55 cd/A, 4.36 lm/w) relative to that of reference device (5.44 cd/A, 3.40 lm/w). Furthermore, the improvement remained even beyond the roll-off effect caused by high current density. However, the blocking-type MQW structure was difficult to optimize due to too intense blocking effect of TPBi layer. The mechanistic differences between trapping-and blocking-type MQW structures were elucidated using hole-only device and SCLC measurements. The experimental results show that trapping-type MQW structure manipulates hole transport effectively to improve charges balance which is essential in enhancing device performance, making it applicable for facile fabrication of efficient OLEDs. (C) 2012 The Electrochemical Society. All rights reserved.
Doi 10.1149/2.009202jss
Wosid WOS:000319445100020
Is Certified Translation No
Dupe Override No
Comments Journal:ECS JOURNAL OF SOLID STATE SCIENCE AND TECHNOLOGY 2162-8769
Is Public Yes