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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 18, Iss. 9 — Apr. 26, 2010
  • pp: 9728–9732

Enhanced light extraction of nonpolar a-plane (11-20) GaN light emitting diodes on sapphire substrates by photo-enhanced chemical wet etching

Younghun Jung, Jihyun Kim, Soohwan Jang, Kwang Hyeon Baik, Yong Gon Seo, and Sung-Min Hwang  »View Author Affiliations

Optics Express, Vol. 18, Issue 9, pp. 9728-9732 (2010)

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The extraction efficiency of nonpolar a-plane (11-20) GaN LEDs on sapphire substrates has been enhanced by selectively etching the mesa sidewall faces and the n-type GaN surfaces with photoenhanced chemical wet etching. Submicron-sized trigonal prisms having prismatic planes of {1-100} were clearly displayed on the n-type GaN surfaces as well as the sidewall face after 5 min etching at 60°C. The radiation patterns have shown that more light is extracted in all directions and the output powers of surface textured a-plane GaN LEDs have increased by 25% compared with control samples. PEC wet etching produced unique feature of etching morphology on the mesa sidewall faces and the n-type GaN surface.

© 2010 OSA

OCIS Codes
(230.0230) Optical devices : Optical devices
(230.3670) Optical devices : Light-emitting diodes
(230.4000) Optical devices : Microstructure fabrication

ToC Category:
Optical Devices

Original Manuscript: April 5, 2010
Revised Manuscript: April 21, 2010
Manuscript Accepted: April 22, 2010
Published: April 23, 2010

Younghun Jung, Jihyun Kim, Soohwan Jang, Kwang Hyeon Baik, Yong Gon Seo, and Sung-Min Hwang, "Enhanced light extraction of nonpolar a-plane (11-20) GaN light emitting diodes on sapphire substrates by photo-enhanced chemical wet etching," Opt. Express 18, 9728-9732 (2010)

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