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Optics Express

Optics Express

  • Editor: Andrew M. Weiner
  • Vol. 21, Iss. 6 — Mar. 25, 2013
  • pp: 7125–7130

An improvement of light extraction efficiency for GaN-based light emitting diodes by selective etched nanorods in periodic microholes

Seung Hwan Kim, Hyun Ho Park, Young Ho Song, Hyung Jo Park, Jae Beom Kim, Seong Ran Jeon, Hyun Jeong, Mun Seok Jeong, and Gye Mo Yang  »View Author Affiliations

Optics Express, Vol. 21, Issue 6, pp. 7125-7130 (2013)

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We have demonstrated the enhancement of a GaN-based light emitting diode (LED) by means of a selective etching technique. A conventional LED structure was periodically etched, to form periodic microholes. It showed an improvement of the light extraction efficiency (LEE) of approximately 15%, compared to that of a conventional LED. Furthermore, nano-sized rods inside the microholes were randomly formed by using a powder mask, resulting in an LEE of 43%. From the result of confocal scanning electroluminescence measurement, the light emission arises mainly from the vicinity of the nanorods in the periodic microholes. Therefore, we found that nanorods randomly distributed in periodic microholes in a LED structure play a significant role in the reduction of total internal reflection, by acting as photon wave-guides and scattering centers. This method would be valuable for the fabrication of high efficiency GaN-based LED, in terms of technical simplification and cost.

© 2013 OSA

OCIS Codes
(160.6000) Materials : Semiconductor materials
(180.1790) Microscopy : Confocal microscopy
(230.3670) Optical devices : Light-emitting diodes
(220.4241) Optical design and fabrication : Nanostructure fabrication

ToC Category:
Optical Devices

Original Manuscript: December 20, 2012
Revised Manuscript: February 20, 2013
Manuscript Accepted: March 1, 2013
Published: March 13, 2013

Seung Hwan Kim, Hyun Ho Park, Young Ho Song, Hyung Jo Park, Jae Beom Kim, Seong Ran Jeon, Hyun Jeong, Mun Seok Jeong, and Gye Mo Yang, "An improvement of light extraction efficiency for GaN-based light emitting diodes by selective etched nanorods in periodic microholes," Opt. Express 21, 7125-7130 (2013)

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