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Optics Express

Optics Express

  • Editor: Andrew M. Weiner
  • Vol. 21, Iss. 22 — Nov. 4, 2013
  • pp: 26774–26779

Near ultraviolet InGaN/AlGaN-based light-emitting diodes with highly reflective tin-doped indium oxide/Al-based reflectors

Chang-Hoon Choi, Jaecheon Han, Jae-Seong Park, and Tae-Yeon Seong  »View Author Affiliations

Optics Express, Vol. 21, Issue 22, pp. 26774-26779 (2013)

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The enhanced light output power of a InGaN/AlGaN-based light-emitting diodes (LEDs) using three different types of highly reflective Sn-doped indium oxide (ITO)/Al-based p-type reflectors, namely, ITO/Al, Cu-doped indium oxide (CIO)/s-ITO(sputtered)/Al, and Ag nano-dots(n-Ag)/CIO/s-ITO/Al, is presented. The ITO/Al-based reflectors exhibit lower reflectance (76 - 84% at 365 nm) than Al only reflector (91.1%). However, unlike Al only n-type contact, the ITO/Al-based contacts to p-GaN show good ohmic characteristics. Near-UV (365 nm) InGaN/AlGaN-based LEDs with ITO/Al, CIO/s-ITO/Al, and n-Ag/CIO/s-ITO/Al reflectors exhibit forward-bias voltages of 3.55, 3.48, and 3.34 V at 20 mA, respectively. The LEDs with the ITO/Al and CIO/s-ITO/Al reflectors exhibit 9.5% and 13.5% higher light output power (at 20 mA), respectively, than the LEDs with the n-Ag/CIO/s-ITO/Al reflector. The improved performance of near UV LEDs is attributed to the high reflectance and low contact resistivity of the ITO/Al-based reflectors, which are better than those of conventional Al-based reflectors.

© 2013 Optical Society of America

OCIS Codes
(230.3670) Optical devices : Light-emitting diodes
(230.4040) Optical devices : Mirrors

ToC Category:
Optical Devices

Original Manuscript: September 12, 2013
Revised Manuscript: October 21, 2013
Manuscript Accepted: October 21, 2013
Published: October 29, 2013

Chang-Hoon Choi, Jaecheon Han, Jae-Seong Park, and Tae-Yeon Seong, "Near ultraviolet InGaN/AlGaN-based light-emitting diodes with highly reflective tin-doped indium oxide/Al-based reflectors," Opt. Express 21, 26774-26779 (2013)

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