Published April 30, 2005 | Version v1
Journal article

Enhancement of electroplex emission by using multi-layer device structure

  • 1. Key Laboratory for Information Storage, Displays and Materials, Beijing 100044 (China)
  • 2. Institute of Optoelectronic Technology, Beijing Jiaotong University, Beijing 100044 (China)
  • 3. Institute of Optoelectronic Technology, Beijing Jiaotong University, Beijing 100044 (China) and Key Laboratory for Information Storage, Displays and Materials, Beijing 100044 (China)

Description

Electroplex emission based on poly(N-vinylcarbazole) (PVK) and 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) has been improved dramatically by using a multi-layer device structure indium-tin oxide (ITO)/poly(3,4-ethylenedioxythiophene): poly(styrenesulphonic acid) (PEDOT:PSS)/PVK/BCP/PVK/BCP/LiF/Al. Electroplex emission at 595 nm has been improved about 10 times under low voltage and four times under high voltage compared to the double layer device ITO/PVK/BCP/Al. The maximum brightness of the device also has been improved about eight times. Bright white emission via electroplex formation can be obtained with Commission International d'Eclairage (CIE) coordinates (0.336, 0.320) at 26 V with a brightness of 123 cd/m2. Based on the analysis of highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) of the materials, we suggest the enhancement is mainly ascribed to the confinement effect of the quantum-well-like multi-layer device structure. Every hole and electron has more possibilities to cross recombination at the PVK/BCP interface

Additional details

Identifiers

DOI
10.1016/j.apsusc.2004.09.080;
PII
S0169-4332(04)01435-7;

Publishing Information

Journal Title
Applied Surface Science
Journal Volume
243
Journal Issue
1-4
Journal Page Range
p. 357-361
ISSN
0169-4332
CODEN
ASUSEE

Optional Information

Copyright
Copyright (c) 2004 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.