Optimization of structure parameters for highly efficient AlGaN based deep ultraviolet light emitting diodes

The efficiency of any LEDs critically depends on its base structure. In this paper, we have reported the dependence of active layer structure on the performance of AlGaN based deep ultraviolet light emitting diodes (LEDs) having emission wavelength at 265 nm which is very crucial for DNA manipulation of most of the water borne harmful pathogens. Advanced device simulations have been performed for the deep UV-LEDs by using SiLENSE module of the SimuLED software tool. We have optimized the number of quantum well, quantum well thickness, aluminum content in electron blocking layer (EBL) and the aluminum content in the barrier region. We have observed that optimization of structural properties plays a crucial role in improving the internal quantum efficiency leading to improvement of overall efficiency of the LEDs. The internal quantum efficiency of the UV LED having an emission wavelength of 265 nm reaches up to 55% when the number of quantum well is fixed to five and each well has a thickness in the order of 1.8 nm with aluminum content as 95% and 62% in EBL and barrier region respectively.