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Energy Express

  • Editor: Christian Seassal
  • Vol. 21, Iss. S6 — Nov. 4, 2013
  • pp: A970–A976

Nano-patterned dual-layer ITO electrode of high brightness blue light emitting diodes using maskless wet etching

Semi Oh, Pei-Chen Su, Yong-Jin Yoon, Soohaeng Cho, Joon-Ho Oh, Tae-Yeon Seong, and Kyoung-Kook Kim  »View Author Affiliations

Optics Express, Vol. 21, Issue S6, pp. A970-A976 (2013)

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We propose a dual-layer transparent Indium Tin Oxide (ITO) top electrode scheme and demonstrate the enhancement of the optical output power of GaN-based light emitting diodes (LEDs). The proposed dual-layer structure is composed of a layer with randomly distributed sphere-like nano-patterns obtained solely by a maskless wet etching process and a pre-annealed bottom layer to maintain current spreading of the electrode. It was observed that the surface morphologies and optoelectronic properties are dependent on etching duration. This electrode significantly improves the optical output power of GaN-based LEDs with an enhancement factor of 2.18 at 100 mA without degradation in electrical property when compared to a reference LED.

© 2013 OSA

OCIS Codes
(160.6000) Materials : Semiconductor materials
(230.3670) Optical devices : Light-emitting diodes
(220.4241) Optical design and fabrication : Nanostructure fabrication

ToC Category:
Light-Emitting Diodes

Original Manuscript: January 14, 2013
Revised Manuscript: March 25, 2013
Manuscript Accepted: April 18, 2013
Published: October 2, 2013

Semi Oh, Pei-Chen Su, Yong-Jin Yoon, Soohaeng Cho, Joon-Ho Oh, Tae-Yeon Seong, and Kyoung-Kook Kim, "Nano-patterned dual-layer ITO electrode of high brightness blue light emitting diodes using maskless wet etching," Opt. Express 21, A970-A976 (2013)

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  1. R. Windisch, B. Dutta, M. Kuijk, A. Knobloch, S. Meinlschmidt, S. Schoberth, P. Kiesel, G. Borghs, G. H. Döhler, P. Heremans, “40% Efficient thin-film surface-textured light-emitting diodes by optimization of natural lithography,” IEEE Trans. Electron. Dev. 47(7), 1492–1498 (2000). [CrossRef]
  2. J. J. Wierer, M. R. Krames, J. E. Epler, N. F. Gardner, M. G. Craford, J. R. Wendt, J. A. Simmons, M. M. Sigalas, “InGaN/GaN quantum-well heterostructure light-emitting diodes employing photonic crystal structure,” Appl. Phys. Lett. 84(19), 3885 (2004). [CrossRef]
  3. X. X. Fu, B. Zhang, X. N. Kang, J. J. Deng, C. Xiong, T. Dai, X. Z. Jiang, T. J. Yu, Z. Z. Chen, G. Y. Zhang, “GaN-based light-emitting diodes with photonic crystals structures fabricated by porous anodic alumina template,” Opt. Express 19(S5Suppl 5), A1104–A1108 (2011). [CrossRef] [PubMed]
  4. K. S. Kim, S.-M. Kim, H. Jeong, G. Y. Jung, “Enhancement of light extraction through the wave-guiding effect of ZnO sub-microrods in InGaN blue light-emitting diodes,” Adv. Funct. Mater. 20(7), 1076–1082 (2010). [CrossRef]
  5. K.-J. Byeon, J.-Y. Cho, J. Kim, H. Park, H. Lee, “Fabrication of SiNx-based photonic crystals on GaN-based LED devices with patterned sapphire substrate by nanoimprint lithography,” Opt. Express 20(10), 11423–11432 (2012). [CrossRef] [PubMed]
  6. T. Fujii, Y. Gao, R. Sharma, E. L. Hu, S. P. DenBaars, S. Nakamura, “Increase in the extraction efficiency of GaN-based light-emitting diodes via surface roughening,” Appl. Phys. Lett. 84(6), 855 (2004). [CrossRef]
  7. S. M. Pan, R. C. Tu, Y. M. Fan, R. C. Yeh, J. T. Hsu, “Improvement of InGaN-GaN light-emitting diodes with surface-textured indium-tin-oxide transparent ohmic contacts,” IEEE Photon. Technol. Lett. 15(5), 649–651 (2003). [CrossRef]
  8. R. H. Horng, C. C. Yang, J. Y. Wu, S. H. Huang, C. E. Lee, D. S. Wuu, “GaN based light-emitting diodes with indium tin oxide texturing window layers using natural lithography,” Appl. Phys. Lett. 86(22), 221101 (2005). [CrossRef]
  9. Q. Zhang, K. H. Li, H. W. Choi, “InGaN light-emitting diodes with indium-tin-oxide sub-micro lenses patterned by nanosphere lithography,” Appl. Phys. Lett. 100(6), 061120 (2012). [CrossRef]
  10. A. P. Vasudev, J. A. Schuller, M. L. Brongersma, “Nanophotonic light trapping with patterned transparent conductive oxides,” Opt. Express 20(S3), A385–A394 (2012). [CrossRef] [PubMed]
  11. D.-S. Leem, T. Lee, T.-Y. Seong, “Enhancement of the light output of GaN-based light-emitting diodes with surface-patterned ITO electrodes by maskless wet-etching,” Solid-State Electron. 51(5), 793 (2007). [CrossRef]
  12. J. E. A. M. van den Meerakker, P. C. Baarslag, W. Walrave, T. J. Vink, J. L. C. Daams, “On the homogeneity of sputter-deposited ITO films Part II. Etching behaviour,” Thin Solid Films 266(2), 152–156 (1995). [CrossRef]

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