Improved Photoluminescence in InGaN/GaN Strained Quantum Wells
DING Li-Zhen1,2, CHEN Hong2**, HE Miao1**, JIANG Yang2, LU Tai-Ping2, DENG Zhen2, CHEN Fang-Sheng1, YANG Fan1, YANG Qi1, ZHANG Yu-Li1
1Laboratory of Nanophotonic Functional Materials and Devices, Institute of Optoelectronic Materials and Technology, South China Normal University, Guangzhou 510631 2Key Laboratory for Renewable Energy, Chinese Academy of Sciences, Beijing Key Laboratory for New Energy Materials and Devices, Beijing National Laboratory for Condense Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190
Abstract：The influence of strain accumulation on optical properties is investigated for InGaN/GaN-based blue light-emitting diodes grown by metal organic vapor-phase epitaxy. It is found that it is possible to reduce the strain relaxation and hence the nonradiative recombination centers in InGaN multi-quantum wells (MQWs) by adopting more InGaN/GaN MQWs pairs. The alleviation of strain relaxation in a superlattice layer results in the crystalline perfection and effective quality improvement of the epitaxial structures. With suitable control of the crystalline quality and reduced strain relaxation in the MQWs, there shows a 4-fold increase in light output luminous efficiency as compared to their conventional counterparts.
2014, Vol. 31 
