Electrically driven, phosphor-free, white light-emitting diodes using gallium nitride-based double concentric truncated pyramid structures

Seung Hyuk Lim, Young Ho Ko, Christophe Rodriguez, Su-Hyun Gong, Yong Hoon Cho

Research output: Contribution to journalArticle

42 Citations (Scopus)


White light-emitting diodes (LEDs) are becoming an alternative general light source, with huge energy savings compared to conventional lighting. However, white LEDs using phosphor(s) suffer from unavoidable Stokes energy converting losses, higher manufacturing cost, and reduced thermal stability. Here, we demonstrate electrically driven, phosphor-free, white LEDs based on three-dimensional gallium nitride structures with double concentric truncated hexagonal pyramids. The electroluminescence spectra are stable with varying current. The origin of the emission wavelength is studied by cathodoluminescence and high-angle annular dark field scanning transmission electron microscopy experiments. Spatial variation of the carrier injection efficiency is also investigated by a comparative analysis between spatially resolved photoluminescence and electroluminescence.

Original languageEnglish
Article numbere16030
JournalLight: Science and Applications
Publication statusPublished - 2016 Feb 12
Externally publishedYes



  • indium gallium nitride
  • light-emitting diodes
  • phosphor-free
  • three-dimensional structures
  • white color

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics

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