Photonic crystal tunnel junction deep ultraviolet light emitting diodes with enhanced light extraction efficiency

We report on the demonstration of top emitting AlGaN tunnel junction deep ultraviolet (UV) light emitting didoes (LEDs) operating at similar to 267 nm. We show, both theoretically and experimentally, that the light extraction efficiency can be enhanced by nearly a factor of two with the incorporation of AlGaN nanowire photonic crystal structures. A peak wall-plug efficiency (WPE) similar to 3.5% and external quantum efficiency (EQE) similar to 5.4% were measured for AlGaN LEDs directly on-wafer without any packaging. This work demonstrates a viable path for achieving high efficiency deep UV LEDs through the integration of AlGaN planar and nanoscale structures. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement