Low Temperature Electroluminescence of AlGaN based UV Edge Emitting LEDs grown by MBE on Bulk AlN Substrates

Ultraviolet (UV) light-emitting diodes (LEDs) based on the AlGaN ultrawide bandgap semiconductor material system hold significant promise for a range of applications, including sterilization, water purification, and high-density optical storage. However, the external quantum efficiency (EQE) of these devices remains limited, primarily due to incomplete understanding of the microscopic processes governing carrier dynamics and recombination mechanisms in these ultrawide bandgap semiconductor materials. Lowtemperature electroluminescence (LT-EL) is a powerful technique for probing these mechanisms. Here we deploy LT-EL to elucidate the fundamental device physics of AlGaN-based UV LEDs to identify key avenues for improving EQE for more efficient UV diode technologies.