Micro-pixel design milliwatt power 254 nm emission light emitting diodes

We report on AlGaN based deep ultraviolet (UV) light emitting diodes (LED) with a novel micro-pixel design and emission at 254 nm. The micro-pixel design was adopted to improve the lateral current spreading and to reduce the operation voltages. For a 4 x 4 and 10 x 10 interconnected 30 mum diameter micro-pixel design, the device series resistances as low as 17 Omega and 11 Omega were measured. For an unpackaged 10 x 10 pixel design LED, pulsed output power as high as 1 mW was measured at a pump current of 1 A which translates to a peak external quantum efficiency of 0.02%.