Enhanced light extraction of a high-power GaN-based light-emitting diode with a nanohemispherical hybrid backside reflector

Jian Kai Liou, Wei Cheng Chen, Ching Hong Chang, Yu Chih Chang, Jung Hui Tsai, Wen Chau Liu

Research output: Contribution to journalArticle

8 Citations (Scopus)


A high-power GaN-based light-emitting diode (LED) with an inductively coupled plasma (ICP)-transferred nanohemispherical hybrid backside reflector is studied. A self-assembled 100 ± 5 nm SiO2 nanosphere monolayer is drop-coated on the backside of a sapphire substrate as a mask to transfer nanohemispherical patterns onto the backside of the sapphire substrate by ICP. Nanohemispherical patterns could be transferred to the deposited backside reflector. Thus, reflected photons could be redirected and scattered into arbitrary directions for light extraction. As compared with a conventional LED without a backside reflector, at 350 mA, the studied device exhibits a 118.2% enhancement in light output power without the degradation of electrical properties. Note that the adhesion between an ICP-transferred sapphire substrate and the hybrid backside reflector is better than when directly inserting an SiO2 nanosphere monolayer in the device. Thus, the process yield could be enhanced for applying in the solid-state lighting.

Original languageEnglish
Article number7194779
Pages (from-to)3296-3301
Number of pages6
JournalIEEE Transactions on Electron Devices
Issue number10
Publication statusPublished - 2015 Oct 1


All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Electrical and Electronic Engineering

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