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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 19, Iss. 2 — Jan. 17, 2011
  • pp: 1113–1121

Highly transparent organic light-emitting diodes with a metallic top electrode: the dual role of a Cs2CO3 layer

Hyunsu Cho, Jung-Min Choi, and Seunghyup Yoo  »View Author Affiliations

Optics Express, Vol. 19, Issue 2, pp. 1113-1121 (2011)

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Highly transparent organic light-emitting diodes (TrOLEDs) are demonstrated using damage-free top cathodes of Cs2CO3/ Ag capped with ZnS layers. The presence of ultrathin Cs2CO3 layers not only improves the electron injection properties but also makes Ag thin films more continuous and uniform, resulting in ideal top electrodes with low sheet resistance and high transmittance. The combination of the uniform Ag morphology enabled by Cs2CO3 and the optimized thickness of ZnS capping layers results in TrOLEDs that have a peak transmittance as large as 80% with a luminous transmittance of 76.4%. These TrOLEDs exhibit a low turn-on voltage of 2.6V due to injection improvement by the Cs2CO3 layers.

© 2011 OSA

OCIS Codes
(230.3670) Optical devices : Light-emitting diodes
(230.4170) Optical devices : Multilayers
(310.6860) Thin films : Thin films, optical properties
(310.6845) Thin films : Thin film devices and applications

ToC Category:
Optical Devices

Original Manuscript: November 24, 2010
Revised Manuscript: December 23, 2010
Manuscript Accepted: December 23, 2010
Published: January 10, 2011

Virtual Issues
Vol. 6, Iss. 2 Virtual Journal for Biomedical Optics

Hyunsu Cho, Jung-Min Choi, and Seunghyup Yoo, "Highly transparent organic light-emitting diodes with a metallic top electrode: the dual role of a Cs2CO3 layer," Opt. Express 19, 1113-1121 (2011)

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