The novel AlGaN-based ultraviolet light-emitting diodes(UV-LEDs) with double superlattice structure(DSL) are proposed and demonstrated by numerical simulation and experimental verification. The DSL consists of 30-peri...The novel AlGaN-based ultraviolet light-emitting diodes(UV-LEDs) with double superlattice structure(DSL) are proposed and demonstrated by numerical simulation and experimental verification. The DSL consists of 30-period Mg modulation-doped p-AlGaN/u-GaN superlattice(SL) and 4-period p-AlGaN/p-GaN SL electron blocking layer, which are used to replace the p-type GaN layer and electron blocking layer of conventional UV-LEDs, respectively. Due to the special effects and interfacial stress, the AlGaN/GaN short-period superlattice can reduce the acceptor ionization energy of the ptype regions, thereby increasing the hole concentration. Meanwhile, the multi-barrier electron blocking layers are effective in suppressing electron leakage and improving hole injection. Experimental results show that the enhancements of 22.5%and 37.9% in the output power and external quantum efficiency at 120 m A appear in the device with double superlattice structure.展开更多
基金supported by the National Key R&D Program of China(Grant Nos.2016YFB0400800,2016YFB0400801,and 2016YFB0400802)the National Natural Science Foundation of China(Grant No.61634005)the Fundamental Research Funds for the Central Universities,China(Grant No.JBZ171101)
文摘The novel AlGaN-based ultraviolet light-emitting diodes(UV-LEDs) with double superlattice structure(DSL) are proposed and demonstrated by numerical simulation and experimental verification. The DSL consists of 30-period Mg modulation-doped p-AlGaN/u-GaN superlattice(SL) and 4-period p-AlGaN/p-GaN SL electron blocking layer, which are used to replace the p-type GaN layer and electron blocking layer of conventional UV-LEDs, respectively. Due to the special effects and interfacial stress, the AlGaN/GaN short-period superlattice can reduce the acceptor ionization energy of the ptype regions, thereby increasing the hole concentration. Meanwhile, the multi-barrier electron blocking layers are effective in suppressing electron leakage and improving hole injection. Experimental results show that the enhancements of 22.5%and 37.9% in the output power and external quantum efficiency at 120 m A appear in the device with double superlattice structure.