Design and Characterization of Polarization-Reversed AlInGaN Based Ultraviolet Light-Emitting Diode

The effect of using polarization-reversed AlInGaN-based quantum well active region in ultraviolet light-emitting diode is numerically investigated. By employing ${\rm Al}_{0.54}{\rm In}_{0.26}{\rm Ga}_{0.20}{\rm N}$ and ${\rm Al}_{0.83}{\rm In}_{0.17}{\rm N}$ as barrier and electron blocking layers, which ably reverse the direction of the polarization in ${\rm Al}_{0.005}{\rm In}_{0.02}{\rm Ga}_{0.975}{\rm N}$ quantum well and provide sufficient potential barrier height to confine electrons in the conduction band, simulation results show that the energy band profile of the ${\rm Al}_{0.005}{\rm In}_{0.02}{\rm Ga}_{0.975}{\rm N}$ quantum well is tilted up, resulting in better carrier confinement and more uniform distribution of carriers in the quantum well. Moreover, the overlap between electron and hole wave functions is increased and the Auger recombination is suppressed effectively, which in turn improves the radiative recombination efficiency.