Molecular beam epitaxy and characterization of AlGaN nanowire ultraviolet light emitting diodes on Al coated Si (0 0 1) substrate

Abstract

We have demonstrated the epitaxial growth of AlGaN nanowires on Al coated Si (0 0 1) substrate. The as-grown nanowires feature diameters of >200 nm and relatively uniform height distribution. AlGaN nanowires with emission wavelengths from 340 nm to 288 nm have been successfully achieved by varying Al/Ga beam equivalent pressure ratio and growth temperature. Detailed structural characterization suggests that AlGaN nanowires grown on Al template are free of dislocations. We have further demonstrated functional AlGaN nanowire deep ultraviolet (DUV) light emitting diodes, which exhibit a turn-on voltage of 7 V and a single peak EL emission at 288 nm. The realization of high quality AlGaN nanostructures on reflective Al template provides a promising approach for achieving high efficiency DUV light emitters.