AlGaN nanowire deep ultraviolet light emitting diodes with graphene electrode

Despite graphene being an attractive transparent conductive electrode for semiconductor deep ultraviolet (UV) light emitting diodes (LEDs), there have been no experimental demonstrations of any kind UV LEDs using a electrode. Moreover, although aluminum gallium nitride (AlGaN) alloys in the format nanowires are appealing platform surface-emitting vertical LEDs, particular, at short wavelengths, few AlGaN nanowire with In this work, we show that transferred can serve as top and devices down to around 240 nm demonstrated. Compared metal, improves both output power external quantum efficiency. Nonetheless, more severe efficiency droop compared metal. Here, attribute heating effect associated large contact resistance be major reason Detailed scanning electron microscopy Raman scattering experiments suggest height nonuniformity is main cause resistance; issue could potentially alleviated by grown selective area epitaxy able produce uniform height. This therefore, not only demonstrates shortest wavelength but also provides viable path wavelengths.