Study of dual-blue light-emitting diodes with asymmetric AlGaN graded barriers

摘要

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.