摘要
In GaN/GaN multiple quantum well（MQW） green light-emitting diodes（LEDs） with varying In GaN quantum well layer thickness are fabricated and characterized. The investigation of luminescence efficiency versus injection current reveals that several physical mechanisms may jointly influence the efficiency droop, resulting in a non-monotonic variation of droop behavior with increasing quantum well（QW） thickness. When the QW is very thin, the increase of In GaN well layer thickness makes the efficiency droop more serious due to the enhancement of polarization effect. When the QW thickness increases further, however, the droop is alleviated significantly, which is mainly ascribed to the enhanced nonradiative recombination process and the weak delocalization effect.
In GaN/GaN multiple quantum well（MQW） green light-emitting diodes（LEDs） with varying In GaN quantum well layer thickness are fabricated and characterized. The investigation of luminescence efficiency versus injection current reveals that several physical mechanisms may jointly influence the efficiency droop, resulting in a non-monotonic variation of droop behavior with increasing quantum well（QW） thickness. When the QW is very thin, the increase of In GaN well layer thickness makes the efficiency droop more serious due to the enhancement of polarization effect. When the QW thickness increases further, however, the droop is alleviated significantly, which is mainly ascribed to the enhanced nonradiative recombination process and the weak delocalization effect.
基金
Project supported by the National Natural Science Foundation of China(Grant Nos.61574135
61574134
61474142
61474110
61377020
61376089
61223005
and 61321063)
the One-Hundred Person Project of the Chinese Academy of Sciences
the Basic Research Project of Jiangsu Province
China(Grant No.BK20130362)
the Scientific Research Fund of Chongqing Municipal Education Commission
China(Grant No.KJ131206)
the Natural Science Foundation of Chongqing Municipal Science and Technology Commission
China(Grant No.cstc2012jj A50036)
