Enhanced Performance in AlGaN Deep-Ultraviolet Light-Emitting Diodes without an Electron Blocking Layer by Using Graded Decreasing Quantum Barrier Structure

With the continuous advancement of technology, the demand for deep ultraviolet (DUV) light sources has gradually increased across various fields. In order to enhance the light output power of AlGaN-based DUV light-emitting diodes (LEDs), this study proposes a quantum barrier (QB) structure with a graded Al composition decrease, based on the removal of the electron blocking layer. Through an analysis of the energy band diagram, it is demonstrated that this structure can increase the effective electron barrier height, effectively suppress electron leakage, and improve hole injection efficiency. This leads to an increase in carrier concentration in the active region, enhancing the recombination efficiency within the quantum wells. At a current of 100 mA, the LED's light output power reached 439 mW, with an internal quantum efficiency of 0.96. This approach provides a new perspective for improving the light-emitting efficiency and reliability of LEDs.