Improving the performance of organic light-emitting diodes containing BCP/LiF/Al by thermal annealing

Author

Sun, J.X. ; Zhu, X.L. ; Yu, X.M. ; Peng, H.J. ; Wong, M. ; Kwok, H.S.

Author_Institution

Dept. of Electr. & Electron. Eng., Hong Kong Univ. of Sci. & Technol.

Volume

2

Issue

2

fYear

2006

fDate

6/1/2006 12:00:00 AM

Firstpage

138

Lastpage

142

Abstract

In this paper, we examined the effect of post-packaging annealing on the performance of organic light-emitting diodes containing tris-(8-hydroxyquinoline) aluminum (Alq,) or 2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) in direct contact with a LiF-Al bilayer cathode. The detailed electroluminescent (EL) characteristics were compared before and after annealing at 70 degC for 5 hrs. It was found that better luminous efficiency as well as greater power efficiency could be achieved for devices with BCP/LiF/Al structure. However, other devices consisting of Alq₃/LiF/Al were less affected. It is believed that the thermal treatment helps to enhance the electron injection for the former, and less helpful for the latter

Keywords

aluminium; annealing; lithium compounds; organic light emitting diodes; 2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline; 5 hrs; 70 C; Alq3 /LiF/Al structure; BCP/LiF/Al structure; bilayer cathode; electroluminescent characteristics; electron injection; greater power efficiency; luminous efficiency; organic light emitting diodes; thermal annealing; tris-(8-hydroxyquinoline) aluminum; Aluminum; Annealing; Business continuity; Charge carrier processes; Electrons; Light emitting diodes; Mass spectroscopy; Organic light emitting diodes; Substrates; Sun; Annealing; light-emitting diodes (LEDs); organic;

fLanguage

English

Journal_Title

Display Technology, Journal of

Publisher

ieee

ISSN

1551-319X

Type

jour

DOI

10.1109/JDT.2006.872304

Filename

1634381