Qi-rong Yan,Yong Zhang,Jun-zheng Li.Study of dual-blue light-emitting diodes with asymmetric AlGaN graded barriers[J].Optoelectronics Letters,2014,10(4):258-261 Study of dual-blue light-emitting diodes with asymmetric AlGaN graded barriers Author Name Affiliation E-mail Qi-rong Yan  Guangdong Vocational School of Polytechnic, Guangzhou, 510500, China  gmyanqirong@163.com  Yong Zhang  Laboratory of Nanophotonic Functional Materials and Devices, Institute of Optoelectronic Materials and Technology, South China Normal University, Guangzhou, 510631, China    Jun-zheng Li  Foshan Nation Star Optoelectronics Co. Ltd., Foshan, 528000, China    Abstract:       A dual-blue light-emitting diode (LED) with asymmetric AlGaN composition-graded barriers but without an AlGaN electron blocking layer (EBL) is analyzed numerically. Its spectral stability and efficiency droop are improved compared with those of the conventional InGaN/GaN quantum well (QW) dual-blue LEDs based on stacking structure of two In0.18Ga0.82N/GaN QWs and two In0.12Ga0.88N/GaN QWs on the same sapphire substrate. The improvement can be attributed to the markedly enhanced injection of holes into the dual-blue active regions and effective reduction of leakage current. Hits: 3811 Download times: 0 View Full Text    Download reader