Title :
Optical Simulation and Fabrication of Near-Ultraviolet LEDs on a Roughened Backside GaN Substrate
Author :
Fu, Yi-Keng ; Lu, Yu-Hsuan ; Xuan, Rong ; Chao, Chia-Hsin ; Su, Yan-Kuin ; Chen, Jenn-Fang
Author_Institution :
Dept. of Opto-Electron. Epitaxy & Devices, Ind. Technol. Res. Inst., Hsinchu, Taiwan
fDate :
3/15/2012 12:00:00 AM
Abstract :
In this letter, the numerical and experimental demonstrations for enhancement of light extraction efficiency in near-ultraviolet light-emitting diodes (LEDs) with a roughened backside on the N-face surface of GaN substrate through a chemical wet-etching process are investigated. It was also found that the increased etching time can increase the height of hexagonal pyramids and decrease the density of hexagonal pyramids. With 20-mA injection current, it was found that forward voltages were 3.13 and 3.16 V while output powers were 13.15 and 27.18 mW for the conventional LED and roughened backside LED, respectively.
Keywords :
III-V semiconductors; etching; gallium compounds; light emitting diodes; optical fabrication; wide band gap semiconductors; chemical wet-etching process; current 20 mA; etching time; hexagonal pyramids; injection current; light extraction efficiency; near-ultraviolet LED; near-ultraviolet light-emitting diodes; optical fabrication; optical simulation; power 13.15 mW; power 27.18 mW; roughened backside substrate; voltage 3.13 V; voltage 3.16 V; Chemicals; Etching; Gallium nitride; Light emitting diodes; Quantum well devices; Substrates; Chemical wet-etching; GaN; light extraction; near-ultraviolet light-emitting diode (NUV LED); simulation;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2011.2182606
