DocumentCode
1258077
Title
High Collection Efficiency Achieved by Photonic Crystal Off- 
Diffractions in Microsized Thin-Film GaN Light-Emitting Diodes
Author
Chu, Ying-Chien ; Su, Yan-Kuin ; Chao, Chia-Hsin ; Yeh, Wen-Yung
Author_Institution
Dept. of Electr. Eng., Nat. Cheng Kung Univ., Tainan, Taiwan
Volume
24
Issue
18
fYear
2012
Firstpage
1635
Lastpage
1637
Abstract
Based on the off-Γ diffractions from a square photonic crystal (PhC), a flat-top far-field profile is achieved in a microsized thin-film light-emitting diode (mTFLED) for higher light-collection efficiency. The PhC mTFLED with a lattice constant of 370 nm and hole depth of 80 nm exhibits two diffractions at ±12°, resulting in a flat-top far-field profile. The off-Γ diffractions improve light-collection efficiency from 6.57% to 10.79% within a ±15° extraction cone. In addition, the light output power of the PhC mTFLED is 2.93 times than that of nonPhC mTFLED.
Keywords
III-V semiconductors; gallium compounds; light emitting diodes; photonic crystals; semiconductor thin films; wide band gap semiconductors; GaN; depth 80 nm; flat-top far-field profile; hole depth; lattice constant; light output power; light-collection efficiency; mTFLED; microsized thin-film light-emitting diodes; photonic crystal off-Γ diffractions; Diffraction; Electrical engineering; Gallium nitride; Lattices; Light emitting diodes; Photonic crystals; Power generation; Flat-top far-field profile; light-collection efficiency; light-emitting diodes (LEDs); photonic crystals (PhCs);
fLanguage
English
Journal_Title
Photonics Technology Letters, IEEE
Publisher
ieee
ISSN
1041-1135
Type
jour
DOI
10.1109/LPT.2012.2211584
Filename
6259828
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