InGaN/GaN multiple quantum wells （MQWs） are grown on planar and maskless periodically grooved sapphires by metal organic vapour phase epitaxy （MOCVD）. High-resolution x-ray rocking curves and transmission electron...InGaN/GaN multiple quantum wells （MQWs） are grown on planar and maskless periodically grooved sapphires by metal organic vapour phase epitaxy （MOCVD）. High-resolution x-ray rocking curves and transmission electron microscopy （TEM） are adopted to characterize the film quality. Compared with the MQWs grown on planar sapphire, the sample grown on grooved sapphire shows better crystalline quality： a remarkable reduction of dislocation densities is achieved. Meanwhile, the MQWs grown on grooved sapphire show two times larger PL intensity at room temperature. Temperature-dependent PL measurements are adopted to investigate the luminescence properties. The luminescence thermal quenching based on a fit to the Arrhenius plot of the normalized integrated PL intensity over the measured temperature range suggests that the nonradiative recombination centres （NRCs） are greatly reduced for the sample grown on grooved sapphire. We assume that the reduction of dislocations which act as NRCs is the main reason for the sample grown on pattern sapphire having higher PL intensity.展开更多
基金supported by the National Natural Science Foundation of China(21203179,11274057,51102036)National Key Basic Research Program of China(973)(2012CB626801)+1 种基金Fundamental Research Funds for the Central Universities,China(DC13010219.B)Science and Technology Project of Liaoning Province,China(2012222009)~~
基金Support by the National High Technology Research and Development Programme of China under Grant Nos 2001AA313120, the National Natural Science Foundation of China under Grant Nos 10474126 and 10574148, and the National Key Basic Research and Development Programme of China under Grant No 2002CB311900.
文摘InGaN/GaN multiple quantum wells （MQWs） are grown on planar and maskless periodically grooved sapphires by metal organic vapour phase epitaxy （MOCVD）. High-resolution x-ray rocking curves and transmission electron microscopy （TEM） are adopted to characterize the film quality. Compared with the MQWs grown on planar sapphire, the sample grown on grooved sapphire shows better crystalline quality： a remarkable reduction of dislocation densities is achieved. Meanwhile, the MQWs grown on grooved sapphire show two times larger PL intensity at room temperature. Temperature-dependent PL measurements are adopted to investigate the luminescence properties. The luminescence thermal quenching based on a fit to the Arrhenius plot of the normalized integrated PL intensity over the measured temperature range suggests that the nonradiative recombination centres （NRCs） are greatly reduced for the sample grown on grooved sapphire. We assume that the reduction of dislocations which act as NRCs is the main reason for the sample grown on pattern sapphire having higher PL intensity.
