Influence of patterned TiO_2/SiO_2 dielectric multilayers for back and front mirror facets on GaN-based laser diodes  

作　　者：陈伟华 胡晓东 代涛 李睿 叶学敏 赵太平 杜为民 杨志坚 张国义 

机构地区：[1]State Key Laboratory for Mesoscopic Physics and Department of Physics,School of Physics,Peking University [2]Institute of Modern Optics,School of Physics,Peking University

出　　处：《Chinese Physics B》2008年第9期3363-3366,共4页中国物理B（英文版）

基　　金：supported by the National High Technology Program of China (Grant No 2007AA03Z403);the National Natural Science Foundation of China (Grant Nos 60776042 and 60477011);National Basic Research Program of China (Grand No2006CB921607)

摘　　要：Ridge InGaN multi-quantum-well-structure （MQW） edge-emitting laser diodes （LDs） were grown on （0001） sapphire substrates by low-pressure metal-organic chemical vapour deposition （MOCVD）. The dielectric TiO2/SiO2 front and back facet coatings as cavity mirror facets of the LDs have been deposited with electron-beam evaporation method. The reflectivity of the designed front coating is about 50% and that of the back high reflective coating is as high as 99.9%. Under pulsed current injection at room temperature, the influences of the dielectric facets were discussed. The threshold current of the ridge GaN-based LDs was decreased after the deposition of the back high reflective dielectric mirrors and decreased again after the front facets were deposited. Above the threshold, the slope efficiency of the LDs with both reflective facets was larger than those with only back facets and without any reflective facets. It is important to design the reflectivity of the front facets for improving the performance of GaN-based LDs.Ridge InGaN multi-quantum-well-structure （MQW） edge-emitting laser diodes （LDs） were grown on （0001） sapphire substrates by low-pressure metal-organic chemical vapour deposition （MOCVD）. The dielectric TiO2/SiO2 front and back facet coatings as cavity mirror facets of the LDs have been deposited with electron-beam evaporation method. The reflectivity of the designed front coating is about 50% and that of the back high reflective coating is as high as 99.9%. Under pulsed current injection at room temperature, the influences of the dielectric facets were discussed. The threshold current of the ridge GaN-based LDs was decreased after the deposition of the back high reflective dielectric mirrors and decreased again after the front facets were deposited. Above the threshold, the slope efficiency of the LDs with both reflective facets was larger than those with only back facets and without any reflective facets. It is important to design the reflectivity of the front facets for improving the performance of GaN-based LDs.

关 键 词：dielectric multilayers GaN-based LD stimulated emission threshold current 

分 类 号：TN365[电子电信—物理电子学]