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Optics Express

Optics Express

  • Editor: C. Martijn de Sterke
  • Vol. 19, Iss. 4 — Feb. 14, 2011
  • pp: 2886–2894

Effect of current spreading on the efficiency droop of InGaN light-emitting diodes

Han-Youl Ryu and Jong-In Shim  »View Author Affiliations

Optics Express, Vol. 19, Issue 4, pp. 2886-2894 (2011)

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We investigate the effects of current spreading on the efficiency droop of InGaN blue light-emitting diodes with lateral injection geometry based on numerical simulation. Current crowding near the mesa edge and the decrease in the current spreading length with current density are shown to cause significant efficiency droop. It is found that the efficiency droop can be reduced considerably as the uniformity of current spreading is improved by increasing the resistivity of the p-type current spreading layer or decreasing the sheet resistance of the n-GaN layer. The droop reduction is well interpreted by the uniformity of carrier distribution in the plane of quantum wells.

© 2011 OSA

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

ToC Category:
Optical Devices

Original Manuscript: December 22, 2010
Revised Manuscript: January 15, 2011
Manuscript Accepted: January 19, 2011
Published: January 31, 2011

Han-Youl Ryu and Jong-In Shim, "Effect of current spreading on the efficiency droop of InGaN light-emitting diodes," Opt. Express 19, 2886-2894 (2011)

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