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Energy Express

Energy Express

  • Editor: Christian Seassal
  • Vol. 22, Iss. S3 — May. 5, 2014
  • pp: A857–A866

Influence of V-pits on the efficiency droop in InGaN/GaN quantum wells

Jaekyun Kim, Yong-Hee Cho, Dong-Su Ko, Xiang-Shu Li, Jung-Yeon Won, Eunha Lee, Seoung-Hwan Park, Jun-Youn Kim, and Sungjin Kim  »View Author Affiliations

Optics Express, Vol. 22, Issue S3, pp. A857-A866 (2014)

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We discuss the influence of V-pits and their energy barrier, originating from its facets of ( 10 1 ¯ 1 ) planes, on the luminescence efficiency of InGaN LEDs. Experimental analysis using cathodoluminescence (CL) exhibits that thin facets of V-pits of InGaN quantum wells (QWs) appear to be effective in improving the emission intensity, preventing the injected carriers from recombining non-radiatively with threading dislocations (TDs). Our theoretical calculation based on the self-consistent approach with adopting k⋅p method reveals that higher V-pit energy barrier heights in InGaN QWs more efficiently suppress the non-radiative recombination at TDs, thus enhancing the internal quantum efficiency (IQE).

© 2014 Optical Society of America

OCIS Codes
(230.3670) Optical devices : Light-emitting diodes
(230.5590) Optical devices : Quantum-well, -wire and -dot devices

ToC Category:
Light-Emitting Diodes

Original Manuscript: January 8, 2014
Revised Manuscript: February 15, 2014
Manuscript Accepted: March 4, 2014
Published: April 10, 2014

Jaekyun Kim, Yong-Hee Cho, Dong-Su Ko, Xiang-Shu Li, Jung-Yeon Won, Eunha Lee, Seoung-Hwan Park, Jun-Youn Kim, and Sungjin Kim, "Influence of V-pits on the efficiency droop in InGaN/GaN quantum wells," Opt. Express 22, A857-A866 (2014)

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