Exploring the Replacement of Toxic Mercury UV Lamp using AlGaN Tunnel Junction in 254 nm-Band DUV LED

Abstract

In the past, low-pressure mercury (Hg) -based deep-ultraviolet (DUV) lamps have been widely used for DUV applications. The exposure of pathogen to DUV radiation at 254 nm emission has been proven to be an effective way of their inactivation in unmanned environment. However, the low-pressure mercury (Hg) DUV lamps are toxic in nature and it consumes a lot of power too. Therefore, in this work, smart and clean single tunnel junction (TJ) AlGaN-based DUV light-emitting diode (LED) at 254 nm peak wavelength has been proposed. The simulated conventional DUV LED device has maximum internal quantum efficiency (IQE) of 50 % with an efficiency droop of 18 % under 200 A/cm2. The performance of the conventional LED can be improved by employing a 5 nm-thin single layer AlGaN TJ. The calculated result shows that AlGaN TJ-based LED has a maximum IQE of 62 % with an efficiency droop of 15 % under higher injection current. In addition, the TJ LED emitted power has been improved by 34 % compared to the conventional LED structure. Such efficient AlGaN DUV LED at 254 nm emission wavelength will be an effective replacement of Hg-DUV lamp in the future.