In this talk, I will discuss using AlGaN nanowires for surface-emitting semiconductor deep UV LEDs at short wavelengths in vertical geometry. I will first show that by using high Al content AlGaN nanowires, devices emitting down to 207 nm can be obtained. The incorporation of polarization engineered layers further improves the device electrical performance significantly, whereas replacing conventional metal top electrode with graphene improves the device optical performance. I will also show in this talk that, by using nanowire template assisted AlN buffer layers, vertical semiconductor deep UV LEDs emitting down to 247 nm can be achieved.
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