Optimization of AlGaN-Based Deep Ultraviolet Light Emitting Diodes with Step-Graded Electron Blocking Layer

AlGaN-based deep ultraviolet light-emitting diodes (DUV-LEDs) experience significant electron leakage due to the high mobility of electrons and weak confinement capability of the active region. To mitigate this issue, step- graded (SG) electron blocking layers (EBLs) are proposed. The DUV-LED fabricated by Yan, with an emission wavelength of 284.5 nm, serves as the reference structure. Using the APSYs software, DUV-LEDs with rectangular EBL and SG EBL are simulated. The results show that the SG EBL contributes to the decreased electron leakage in the p-type region, the increased hole injection efficiency, and the enhanced radiation recombination rate of the DUV-LEDs. At an injection current of 60 mA, the output power reaches 9.91 mW, representing an improvement. The SG EBL offers a theoretical framework for addressing electron leakage issues in DUV-LEDs.