The physical mechanism of improving the photoelectric performance of InGaN/AlGaN‐based near UV light‐emitting diode (LED) with convex quantum barrier and staggered quantum well (QW) is studied by numerical simulation. The simulation results indicate that the voltage–current characteristics of the LED structure with convex quantum barrier and staggered QW are effectively improved compared with the traditional multiple quantum well (MQW) structure, and its electroluminescence (EL) intensity and light output power are significantly improved. The main physical mechanisms are: on the one hand, the convex quantum barrier with a lower average Al component can reduce the polarization electric field at the interface between the quantum barrier and QW as well as the effective potential barrier of holes, improve the spatial separation of electron and hole wave functions, promote the injection efficiency of carriers, and improve the uniformity of carrier distribution in the MQWs active region; On the other hand, staggered QWs can provide stronger carrier confinement effect and further increase the overlap of electron and hole wave functions, so as to improve the carrier radiative recombination efficiency; In a word, this work provides a valuable reference for obtaining high‐performance near‐ultraviolet LED.

Compared with conventional InGaN Quantum Wells (QWs), staggered InGaN QWs offer improved optical and electronic properties. This work studied the carrier concentration, band structure, overlap of hole and electron wave functions, and polarization field of three-layer staggered QWs in the blue spectral region and analyzed them in detail theoretically to explore the source and the dominant mechanism for improvement. Although theoretical studies indicate that the polarization field in QWs of staggered InGaN QWs is larger, the carrier confinement effect is stronger, and the carrier distribution is more uniform. Therefore, three-layer staggered QWs can improve overlapping of the hole and electron wave functions and then enhance the recombination rate so as to increase the optical output power and electroluminescence intensity. Moreover, the performance of the staggered structure C with the lowest indium content at the center of the well is better than that of the step-staggered structure B.

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Herein, a novel AlGaN‐based multiple quantum well (MQW) deep UV light‐emitting diode (DUV‐LED) structure with two parts linearly graded barriers is presented. The simulation result shows that at a current of 50 mA, the light output power of the DUV‐LED with two parts linearly graded barrier MQWs has significant improvement as compared to stationary barriers. The electroluminescence spectrum and radiative recombination rate of novel DUV‐LEDs are also larger more than twice that of the conventional QW structure. The reason is that the injection efficiency of holes is increased which helps improve the hole and electron concentration in the active area. Meanwhile, the electric field is also decreased by using two parts linearly graded quantum barriers, and according to reduce the electric field the quantum‐confined Stark effect and the bend of the energy band get relieved.