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Energy Express

  • Editor: Christian Seassal
  • Vol. 22, Iss. S3 — May. 5, 2014
  • pp: A833–A841

Enhanced electroluminescence using Ta2O5/ZnO/HfO2 asymmetric double heterostructure in ZnO/GaN-based light emitting diodes

Hao Long, Songzhan Li, Xiaoming Mo, Haoning Wang, Zhao Chen, Zhe Chuan Feng, and Guojia Fang  »View Author Affiliations

Optics Express, Vol. 22, Issue S3, pp. A833-A841 (2014)

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ZnO/GaN-based light-emitting diodes (LEDs) with improved asymmetric double heterostructure of Ta2O5/ZnO/HfO2 have been fabricated. Electroluminescence (EL) performance has been enhanced by the HfO2 electron blocking layer and further improved by continuing inserting the Ta2O5 hole blocking layer. The origins of the emission have been identified, which indicated that the Ta2O5/ZnO/HfO2 asymmetric structure could more effectively confine carriers in the active i-ZnO layer and meanwhile suppresses of radiation from GaN. This device exhibits superior stability in long-time running. It’s hoped that the asymmetric double heterostructure may be helpful for the development of the future ZnO-based LEDs.

© 2014 Optical Society of America

OCIS Codes
(160.6000) Materials : Semiconductor materials
(230.2090) Optical devices : Electro-optical devices
(230.3670) Optical devices : Light-emitting diodes
(310.4165) Thin films : Multilayer design

ToC Category:
Light-Emitting Diodes

Original Manuscript: February 14, 2014
Revised Manuscript: April 1, 2014
Manuscript Accepted: April 1, 2014
Published: April 10, 2014

Hao Long, Songzhan Li, Xiaoming Mo, Haoning Wang, Zhao Chen, Zhe Chuan Feng, and Guojia Fang, "Enhanced electroluminescence using Ta2O5/ZnO/HfO2 asymmetric double heterostructure in ZnO/GaN-based light emitting diodes," Opt. Express 22, A833-A841 (2014)

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