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Applied Optics

Applied Optics

APPLICATIONS-CENTERED RESEARCH IN OPTICS

  • Editor: Joseph N. Mait
  • Vol. 51, Iss. 23 — Aug. 10, 2012
  • pp: 5596–5600

Evaluation of metal/indium-tin-oxide for transparent low-resistance contacts to p-type GaN

Wenting Hou, Christoph Stark, Shi You, Liang Zhao, Theeradetch Detchprohm, and Christian Wetzel  »View Author Affiliations


Applied Optics, Vol. 51, Issue 23, pp. 5596-5600 (2012)
http://dx.doi.org/10.1364/AO.51.005596


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Abstract

In search of a better transparent contact to p-GaN, we analyze various metal/indium-tin-oxide (ITO) (Ag/ITO, AgCu/ITO, Ni/ITO, and NiZn/ITO) contact schemes and compare to Ni/Au, NiZn/Ag, and ITO. The metal layer boosts conductivity while the ITO thickness can be adjusted to constructive transmission interference on GaN that exceeds extraction from bare GaN. We find a best compromise for an Ag/ITO (3nm/67nm) ohmic contact with a relative transmittance of 97% of the bare GaN near 530 nm and a specific contact resistance of 0.03Ω·cm2. The contact proves suitable for green light-emitting diodes in epi-up geometry.

© 2012 Optical Society of America

OCIS Codes
(230.3670) Optical devices : Light-emitting diodes
(310.7005) Thin films : Transparent conductive coatings

ToC Category:
Optical Devices

History
Original Manuscript: March 12, 2012
Revised Manuscript: June 27, 2012
Manuscript Accepted: July 8, 2012
Published: August 2, 2012

Citation
Wenting Hou, Christoph Stark, Shi You, Liang Zhao, Theeradetch Detchprohm, and Christian Wetzel, "Evaluation of metal/indium-tin-oxide for transparent low-resistance contacts to p-type GaN," Appl. Opt. 51, 5596-5600 (2012)
http://www.opticsinfobase.org/ao/abstract.cfm?URI=ao-51-23-5596


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