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Energy Express

Energy Express

  • Editor: Bernard Kippelen
  • Vol. 20, Iss. S2 — Mar. 12, 2012
  • pp: A287–A292

Enhancement of wall-plug efficiency in vertical InGaN/GaN LEDs by improved current spreading

Jun Ho Son, Buem Joon Kim, Chul Jong Ryu, Yang Hee Song, Hwan Keon Lee, Joo Won Choi, and Jong-Lam Lee  »View Author Affiliations

Optics Express, Vol. 20, Issue S2, pp. A287-A292 (2012)

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We present the enhancement of wall-plug efficiency in vertical InGaN/GaN light-emitting diodes (V-LEDs) by improved current spreading with a novel Al2O3 current blocking layer (CBL). The Al2O3 CBL deposited by electron-beam evaporation shows high transmittance and good corrosion resistance to acidic solutions. V-LEDs with an Al2O3 CBL show similar light output power but lower forward voltage as compared to those with a SiO2 CBL deposited by plasma-enhanced chemical vapor deposition. As a result, the wall-plug efficiency of V-LEDs with an Al2O3 CBL at 500 mA was improved by 5% as compared to those with a SiO2 CBL, and by 19% as compared to those without a CBL.

© 2012 OSA

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

ToC Category:
Light-Emitting Diodes

Original Manuscript: November 23, 2011
Revised Manuscript: January 17, 2012
Manuscript Accepted: February 17, 2012
Published: February 24, 2012

Jun Ho Son, Buem Joon Kim, Chul Jong Ryu, Yang Hee Song, Hwan Keon Lee, Joo Won Choi, and Jong-Lam Lee, "Enhancement of wall-plug efficiency in vertical InGaN/GaN LEDs by improved current spreading," Opt. Express 20, A287-A292 (2012)

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