Effect of Patterned Sapphire Substrate Shape on Light Output Power of GaN-Based LEDs

Author

Huang, Xiao-Hui ; Liu, Jian-Ping ; Fan, Ya-Ying ; Kong, Jun-Jie ; Yang, Hui ; Wang, Huai-Bing

Author_Institution

Dept. of Nano Device, Suzhou Inst. of Nano-Tech & Nano-Bionics, Suzhou, China

Volume

23

Issue

14

fYear

2011

fDate

7/15/2011 12:00:00 AM

Firstpage

944

Lastpage

946

Abstract

An optical simulation including reflection and refraction is used to simulate the light illumination intensity of gallium nitride (GaN)-based light-emitting diodes (LEDs) on varied patterned sapphire substrates (PSS) with different slanted angles and fill factors (f ). It is found that a micro pyramid array with a slanted angle from 25° to 60° is able to effectively improve illumination intensity which reaches to summit as the slanted angle is around 33°. And illumination intensity enhances monotonously as f increases. In addition to the mentioned work, epitaxial growth of GaN-LEDs on PSS is investigated for comparison. The output power of GaN-LEDs on PSS increases with simulated light illumination intensity increasing. The experimental results prove the simulation.

Keywords

III-V semiconductors; epitaxial growth; gallium compounds; light emitting diodes; light refraction; lighting; reflectivity; wide band gap semiconductors; Al₂O₃; GaN; LED; epitaxial growth; fill factors; gallium nitride-based light-emitting diodes; light illumination intensity; light output power; micropyramid array; optical reflection; optical refraction; optical simulation; patterned sapphire substrate; slanted angles; Arrays; Gallium nitride; Light emitting diodes; Lighting; Power generation; Reflection; Substrates; GaN; illumination intensity; light-emitting diode (LED); patterned sapphire substrate (PSS);

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/LPT.2011.2142397

Filename

5750032