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Optics Express

Optics Express

  • Editor: Michael Duncan
  • Vol. 13, Iss. 1 — Jan. 10, 2005
  • pp: 26–31

Enhanced performance of tris-(8-hydroxyquinoline) aluminum-based organic light-emitting devices with LiF/Mg:Ag/Ag cathode

B. J. Chen, X. W. Sun, K. S. Wong, and X. Hu  »View Author Affiliations

Optics Express, Vol. 13, Issue 1, pp. 26-31 (2005)

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The device characteristics of organic light-emitting devices based on tris-(8-hydroxyqunoline) aluminum devices with LiF/Mg:Ag/Ag cathodes were investigated. The devices with Mg:Ag/Ag, LiF/Al and Al-only cathodes were also fabricated in the same run for comparison. Similar to the LiF/Al cathodes, the LiF/Mg:Ag/Ag cathode greatly improved the performance of the device over the Mg:Ag/Ag cathode. A LiF layer of 0.5 nm significantly enhanced the electron injection and resulted in lower turn-on voltage and increased device efficiency. The turn-on voltage of the device with 0.5 nm LiF as buffered layer is as low as 2.8 V. At injection current density of 20 mA/cm2, the current efficiency and power efficiency of the device is 5.56 cd/A and 1.94 lm/W, respectively. Compared to the device with Mg:Ag/Ag only cathode, the turn-on voltage is 1.6 V lower, the current efficiency improved by 75 %, and power efficiency is almost double. The performance of the device is also much improved over the device with LiF/Al cathode.

© 2005 Optical Society of America

OCIS Codes
(160.4890) Materials : Organic materials
(230.3670) Optical devices : Light-emitting diodes
(310.6860) Thin films : Thin films, optical properties

ToC Category:
Research Papers

Original Manuscript: October 25, 2004
Revised Manuscript: December 15, 2004
Manuscript Accepted: December 18, 2004
Published: January 10, 2005

B. J. Chen, X. W. Sun, K. S. Wong, and X. Hu, "Enhanced performance of tris-(8-hydroxyquinoline) aluminum-based organic light-emitting devices with LiF/Mg:Ag/Ag cathode," Opt. Express 13, 26-31 (2005)

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