GaN Free Graded Hole Source Layer Terminated Structure for Efficient AlGaN-Based UV-C LED

In this simulation study, we replace the p-GaN and p-Al<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.65</inf>Ga<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.35</inf>N layers with graded p-Al<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</inf>Ga<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1-x</inf>N layer (x = 0.65-0) to improve the light extraction efficiency and internal quantum efficiency (IQE). This enhances the hole supply by varying the polarization charge density (also reduces the resistivity of the p-AlGaN layer), increases the hole concentration by ~2.5-fold in the final proposed structure, and enhances the radiative recombination rate in the active region. This increases the maximum IQE by ~49% in the final proposed structure.