Light Extraction Enhancement of a GaN-Based Light-Emitting Diode Through Grating-Patterned Photoelectrochemical Surface Etching With Phase Mask Interferometry

Author

Lin, Cheng-Hung ; Chen, Cheng-Yen ; Yeh, Dong-Ming ; Yang, Chih-Chung

Author_Institution

Dept. of Electr. Eng., Nat. Taiwan Univ., Taipei, Taiwan

Volume

22

Issue

9

fYear

2010

fDate

5/1/2010 12:00:00 AM

Firstpage

640

Lastpage

642

Abstract

The enhancement of light extraction by fabricating a surface grating structure around the mesa of a light-emitting diode (LED) with an approach combining photoelectrochemical (PEC) wet etching and phase mask interferometry is demonstrated. The PEC etching rate is controlled by the intensity of illuminating UV light, which is spatially modulated by the fringe pattern of phase mask interferometry, for forming the grating structure. Without affecting the resistance characteristics of the device, the diffraction of such a grating structure leads to LED output enhancement by > 43% on either the top or bottom side.

Keywords

III-V semiconductors; diffraction gratings; etching; gallium compounds; light emitting diodes; wide band gap semiconductors; GaN; PEC etching rate; fringe pattern; grating-patterned photoelectrochemical surface etching; illuminating UV light; light extraction enhancement; light-emitting diode; phase mask interferometry; photoelectrochemical wet etching; resistance characteristics; surface grating structure; Diffraction; Dry etching; Gratings; Holography; Light emitting diodes; Mass production; Optical interferometry; Rough surfaces; Surface roughness; Wet etching; Light-emitting diode (LED); light extraction; photoelectrochemical (PEC) etching;

fLanguage

English

Journal_Title

Photonics Technology Letters, IEEE

Publisher

ieee

ISSN

1041-1135

Type

jour

DOI

10.1109/LPT.2010.2043093

Filename

5444561