High-brightness vertical gan-based light-emitting diodes with hexagonally close-packed micrometer array structures

Kyeong Jae Byeon, Joong Yeon Cho, June O. Song, Sang Youl Lee, Heon Lee

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

A high-brightness GaN-based vertical light-emitting diode (VLED) was demonstrated by introducing a large-area low-cost direct printing process. A hexagonally close-packed micrometer convex array was fabricated on the n-GaN top layer of the VLED by direct printing using a hydrogen silsesquioxane solution and subsequent inductively coupled plasma etching. To confirm that the enhancement of light extraction by this structure, a conventional wet-chemical-etched structure was also fabricated on the n-GaN top layer of the VLED, yielding randomly oriented pyramid structures on the layer. Both VLEDs showed much stronger electroluminescence emission than an unpatterned VLED. However, the micrometer convex array improved the light extraction significantly more than the random pyramid structure owing to its greater ability to enlarge the light escape cone, attributed to its 50°-tapered profile and large extraction area. After chip packaging with silicone encapsulation, the light output power of the micropatterned VLED was 11.4% and 106% greater than those of the wet-etched and unpatterned VLEDs, respectively, under a 350-mA drive current.

Original languageEnglish
Article number6678212
JournalIEEE Photonics Journal
Volume5
Issue number6
DOIs
Publication statusPublished - 2013 Dec 1

Fingerprint

Light emitting diodes
micrometers
Luminance
brightness
light emitting diodes
pyramids
printing
Printing
Plasma etching
Electroluminescence
Inductively coupled plasma
silicones
plasma etching
Encapsulation
packaging
Silicones
electroluminescence
escape
Cones
Packaging

Keywords

  • Light-emitting diodes (LEDs)
  • microstructure fabrication

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Atomic and Molecular Physics, and Optics

Cite this

High-brightness vertical gan-based light-emitting diodes with hexagonally close-packed micrometer array structures. / Byeon, Kyeong Jae; Cho, Joong Yeon; Song, June O.; Lee, Sang Youl; Lee, Heon.

In: IEEE Photonics Journal, Vol. 5, No. 6, 6678212, 01.12.2013.

Research output: Contribution to journalArticle

Byeon, Kyeong Jae ; Cho, Joong Yeon ; Song, June O. ; Lee, Sang Youl ; Lee, Heon. / High-brightness vertical gan-based light-emitting diodes with hexagonally close-packed micrometer array structures. In: IEEE Photonics Journal. 2013 ; Vol. 5, No. 6.
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