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Virtual Journal for Biomedical Optics

Virtual Journal for Biomedical Optics


  • Editors: Andrew Dunn and Anthony Durkin
  • Vol. 7, Iss. 7 — Jun. 25, 2012

Enhancement of light output power in GaN-based light-emitting diodes using hydrothermally grown ZnO micro-walls

Hyun Jeong, Yong Hwan Kim, Tae Hoon Seo, Hong Seok Lee, Jun Sung Kim, Eun-Kyung Suh, and Mun Seok Jeong  »View Author Affiliations

Optics Express, Vol. 20, Issue 10, pp. 10597-10604 (2012)

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We report on the efficiency enhancement in GaN-based light-emitting diodes (LEDs) using ZnO micro-walls grown by a hydrothermal method. The formation of ZnO micro-walls at the indium tin oxide (ITO) border on the LED structure is explained by the heterogeneous nucleation effect. The light output power of LEDs with ZnO micro-walls operated at 20 mA was found to increase by approximately 30% compared to conventional LEDs. Moreover, the finding of nearly the same current-voltage characteristics of GaN-based LEDs with and without a ZnO micro-wall shows that the ZnO micro-wall does not influence the electrical properties of the device but only leads to an increase in the light extraction efficiency. From the confocal scanning electroluminescence results, we confirm that ZnO micro-walls enhance the light output power via the photon wave-guiding effect.

© 2012 OSA

OCIS Codes
(160.6000) Materials : Semiconductor materials
(180.1790) Microscopy : Confocal microscopy
(220.4000) Optical design and fabrication : Microstructure fabrication
(230.3670) Optical devices : Light-emitting diodes

ToC Category:
Optical Devices

Original Manuscript: March 5, 2012
Revised Manuscript: April 5, 2012
Manuscript Accepted: April 6, 2012
Published: April 24, 2012

Virtual Issues
Vol. 7, Iss. 7 Virtual Journal for Biomedical Optics

Hyun Jeong, Yong Hwan Kim, Tae Hoon Seo, Hong Seok Lee, Jun Sung Kim, Eun-Kyung Suh, and Mun Seok Jeong, "Enhancement of light output power in GaN-based light-emitting diodes using hydrothermally grown ZnO micro-walls," Opt. Express 20, 10597-10604 (2012)

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