Title :
Enhanced light output of GaN-based thin-film flip-chip light-emitting diodes by surface texturing using laser ablation and chemical etching
Author :
Tseng-Hsing Lin ; Shui-Jinn Wang ; Yung-Chun Tu ; Chien-Hsiung Hung ; Zong-Sian You ; Yu-Hsueh Chin
Author_Institution :
Dept. of Electr. Eng., Nat. Cheng Kung Univ., Tainan, Taiwan
Abstract :
A surface texturing scheme using ablation etching by KrF excimer laser irradiation and chemical wet etching is demonstrated to improve the light-extraction efficiency of GaN-based thin-film flip-chip light-emitting diodes (TFFC-LED). Both simulated and experimental results on the light emission characteristics are presented and discussed. For the TFFC-LED (die size of 1×1 mm2) with the proposed surface roughening scheme, enhancements in light output power (LOP) by 13.08% (12.81%) and wall-plug efficiency (WPE) by 2.87% (2.25%) at 350 mA (700 mA) as compared with that of the TFFC-LED without surface texturing are achieved experimentally.
Keywords :
III-V semiconductors; etching; excimers; flip-chip devices; gallium compounds; laser ablation; light emitting diodes; surface roughness; surface texture; GaN; GaN-based thin-film flip-chip light-emitting diodes; KrF; KrF excimer laser irradiation; LOP; TFFC-LED; WPE; ablation etching; chemical wet etching; current 350 mA; current 700 mA; light output power; light-extraction efficiency; surface roughening scheme; wall-plug efficiency; Etching; Light emitting diodes; Radiation effects; Rough surfaces; Surface emitting lasers; Surface roughness;
Conference_Titel :
Device Research Conference (DRC), 2015 73rd Annual
Conference_Location :
Columbus, OH
Print_ISBN :
978-1-4673-8134-5
DOI :
10.1109/DRC.2015.7175586