A comparative study of electrode effects on the electrical and luminescent characteristics of Alq3/TPD OLED:: Improvements due to conductive polymer (PEDOT) anode

被引：57
作者：
Mu, H. [1 ]
Li, W. [1 ]
Jones, R. [1 ]
Steckl, A. [1 ]
Klotzkin, D. [1 ]
机构：
[1] Univ Cincinnati, Dept Elect & Comp Engn & Comp Sci, Cincinnati, OH 45221 USA
来源：
JOURNAL OF LUMINESCENCE | 2007年 / 126卷 / 01期
关键词：
PEDOT; OLED; organic luminescence devices;
D O I：
10.1016/j.jlumin.2006.07.005
中图分类号：
O43 [光学];
学科分类号：
070207 ; 0803 ;
摘要：
The performance of organic light emitting device (OLED) structures, based on identically fabricated Alq(3)/TPD active regions, with various anode and cathode electrode structures are compared, and performance differences related to the different anode structure. The best performance was achieved with a conductive polymer, 3,4-polyethylenedioxythiopene-polystyrenesultonate (PEDOT), used as an anode layer, yielding a brightness of 1720cd/m(2) at 25V, a turn-on voltage of 3V, and electroluminescence (EL) efficiency and external quantum efficiency of 8.2 cd/A and 2%, respectively, at a brightness of 100 cd/m(2) and 5V. Compared to a baseline device (TPD/Alq(3)/Al), PEDOT anodes substantially reduce the turn-on voltage and made current injection almost linear after turn-on, whiles devices incorporating a LiF and CuPc layers significantly improved device efficiency while slightly improving turn-on voltage and maintaining superlinear I V injection. This is attributed to the reduced barrier at the organic-organic interface in PEDOT, the 'ladder' effect of stepping the band offset over several interfaces, and the favorable PEDOT film morphology. The benefit of the PEDOT anode is clearly seen in the improvement in device brightness and the high external quantum efficiency obtained. (C) 2006 Elsevier B.V. All rights reserved.
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页码：225 / 229
页数：5
相关论文
共 22 条
[1]   Hole injection from an ITO|PEDT anode into the hole transporting layer of an OLED probed by bias induced absorption [J].
Book, K ;
Bässler, H ;
Elschner, A ;
Kirchmeyer, S .
ORGANIC ELECTRONICS, 2003, 4 (04) :227-232
[2]   RELIABILITY AND DEGRADATION OF ORGANIC LIGHT-EMITTING DEVICES [J].
BURROWS, PE ;
BULOVIC, V ;
FORREST, SR ;
SAPOCHAK, LS ;
MCCARTY, DM ;
THOMPSON, ME .
APPLIED PHYSICS LETTERS, 1994, 65 (23) :2922-2924
[3]   Plasma treatments of indium tin oxide anodes in carbon tetrafluorinde (CF4)/oxygen (O2) to improve the performance of organic light-emitting diodes [J].
Chan, IM ;
Hong, FCN .
THIN SOLID FILMS, 2003, 444 (1-2) :254-259
[4]   OLED matrix displays: in-line process technology and fundamentals [J].
Dobbertin, T ;
Becker, E ;
Benstem, I ;
Ginev, G ;
Heithecker, D ;
Johannes, HH ;
Metzdorf, D ;
Neuner, H ;
Parashkov, R ;
Kowalsky, W .
THIN SOLID FILMS, 2003, 442 (1-2) :132-139
[5]  
FUJIKAWA H, 2000, MAT RES SOC S P, V621
[6]   Electron injection enhancement by diamond-like carbon film in organic electroluminescence devices [J].
Han, DW ;
Jeong, SM ;
Baik, HK ;
Lee, SJ ;
Yang, NC ;
Suh, DH .
THIN SOLID FILMS, 2002, 420 :190-194
[7]   Very high-efficiency and low voltage phosphorescent organic light-emitting diodes based on a p-i-n junction [J].
He, GF ;
Schneider, O ;
Qin, DS ;
Zhou, X ;
Pfeiffer, M ;
Leo, K .
JOURNAL OF APPLIED PHYSICS, 2004, 95 (10) :5773-5777
[8]   BRIGHT RED LIGHT-EMITTING ORGANIC ELECTROLUMINESCENT DEVICES HAVING A EUROPIUM COMPLEX AS AN EMITTER [J].
KIDO, J ;
HAYASE, H ;
HONGAWA, K ;
NAGAI, K ;
OKUYAMA, K .
APPLIED PHYSICS LETTERS, 1994, 65 (17) :2124-2126
[9]   Effect of aluminum doping on zinc oxide thin films grown by pulsed laser deposition for organic light-emitting devices [J].
Kim, H ;
Piqué, A ;
Horwitz, JS ;
Murata, H ;
Kafafi, ZH ;
Gilmore, CM ;
Chrisey, DB .
THIN SOLID FILMS, 2000, 377 (377-378) :798-802
[10]   Effect of annealing on the electrical properties and morphology of a conducting polymer used as an anode in organic light-emitting devices [J].
Kim, WH ;
Kushto, GP ;
Kim, H ;
Kafafi, ZH .
JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS, 2003, 41 (21) :2522-2528
123