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Energy Express

  • Editor: Christian Seassal
  • Vol. 21, Iss. S1 — Jan. 14, 2013
  • pp: A190–A200

Dependence of efficiencies in GaN-based vertical blue light-emitting diodes on the thickness and doping concentration of the n-GaN layer

Han-Youl Ryu, Ki-Seong Jeon, Min-Goo Kang, Yunho Choi, and Jeong-Soo Lee  »View Author Affiliations

Optics Express, Vol. 21, Issue S1, pp. A190-A200 (2013)

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We investigate the dependence of various efficiencies in GaN-based vertical blue light-emitting diode (LED) structures on the thickness and doping concentration of the n-GaN layer by using numerical simulations. The electrical efficiency (EE) and the internal quantum efficiency (IQE) are found to increase as the thickness or doping concentration increases due to the improvement of current spreading. On the contrary, the light extraction efficiency (LEE) decreases with increasing doping concentration or n-GaN thickness by the free-carrier absorption. By combining the results of EE, IQE, and LEE, wall-plug efficiency (WPE) of the vertical LED is calculated, and the optimum thickness and doping concentration of the n-GaN layer is found for obtaining the maximum WPE.

© 2013 OSA

OCIS Codes
(230.0250) Optical devices : Optoelectronics
(230.3670) Optical devices : Light-emitting diodes

ToC Category:
Light-Emitting Diodes

Original Manuscript: October 4, 2012
Revised Manuscript: November 22, 2012
Manuscript Accepted: December 12, 2012
Published: January 8, 2013

Han-Youl Ryu, Ki-Seong Jeon, Min-Goo Kang, Yunho Choi, and Jeong-Soo Lee, "Dependence of efficiencies in GaN-based vertical blue light-emitting diodes on the thickness and doping concentration of the n-GaN layer," Opt. Express 21, A190-A200 (2013)

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