Though AlGaN ultraviolet (UV) light-emitting diodes (LEDs) have been explored widely, their performance is still limited in the UV B and C regions due to several challenges. Electron leakage is one of the prominent reasons behind the poor performance of AlGaN deep UV LEDs. This problem can be mitigated by integrating the electron-blocking layer (EBL) between the active region and p-region to an extent, not entirely due to the own disadvantages of the EBL. In this regard, we report the achievement of high-performance EBL free AlGaN LEDs using a strip-in-a-barrier structure operating in the UV B and C regions, particularly at 254 nm and 292 nm wavelengths, respectively. Here, we have engineered each quantum barrier by integrating a 1 nm optimized intrinsic AlGaN strip layer in the middle of the QB. The resulting structure could significantly reduce the electron overflow and enhance the output power by ~1.87 times and ~1.48 times for 254 nm and 292 nm LEDs, respectively, compared to the conventional structure. Moreover, internal quantum efficiency droop is reduced notably in the proposed structure at 254 nm and 292 nm wavelengths.
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