Improvement of AlGaN-based deep ultraviolet light-emitting diodes by using a graded AlGaN superlattice hole reservoir layer

The AlGaN-based deep ultraviolet light emitting diodes (DUV-LEDs) with a graded superlattice hole reservoir layer (HRL) can significantly enhance hole injection efficiency, compared with the traditional LED. We have systematically studied by APSYS software. The application of new structure can obtain higher output power and carrier concentrations, and further influence the carrier recombination rate. The DUV-LEDs with a graded superlattice HRL can obviously improve internal quantum efficiency (IQE) and alleviate efficiency droop. The improved performance is mainly attributed to the higher electron potential height and lower hole potential height, so it enhances electron confinement and hole injection. Thereby, the proposed structure effectively improve the photoelectric performance.