Enhanced Light Output of GaN-Based Light-Emitting Diodes by Using Omnidirectional Sidewall Reflectors

Author

Kim, Hyunsoo ; Baik Kwang Hyeon ; Cho, Jaehee ; Kim, Kyoung-Kook ; Lee, Sung-Nam ; Sone, Cheolsoo ; Park, YongJo ; Seong, Tae-Yeon

Author_Institution

Korea Univ., Seoul

Volume

19

Issue

19

fYear

2007

Firstpage

1562

Lastpage

1564

Abstract

We report on the enhancement of light output in GaN-based light-emitting diodes (LEDs) by using omnidirectional sidewall reflectors. Optical ray-tracing simulation results show that the light extraction efficiency of LEDs can vary in the range of 15.0%-24.4%, depending on the mesa depth, reflectivity, and profile angle of mesa sidewalls. Based on these findings, LEDs are fabricated with SiO₂-Al omnidirectional sidewall reflectors (at a mesa depth of 1.6 m and a sidewall profile-angle of 42deg). The LEDs show an enhancement of the light output by 18%, as compared with reference LEDs.

Keywords

III-V semiconductors; aluminium; gallium compounds; light emitting diodes; optical fabrication; ray tracing; reflectivity; silicon compounds; wide band gap semiconductors; GaN - Interface; LED fabrication; SiO₂-Al - Interface; depth 1.6 mum; efficiency 15.0 percent to 24.4 percent; light extraction efficiency; light output enhancement; light-emitting diodes; mesa sidewall profile-angle; omnidirectional sidewall reflectors; optical ray-tracing simulation; reflectivity; Dry etching; Electrodes; Fabrication; Light emitting diodes; Optical films; Optical reflection; Plasma applications; Plasma chemistry; Ray tracing; Reflectivity; GaN; light-emitting diode (LED); reflector; sidewall;

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/LPT.2007.904325

Filename

4303165