[1] [1] XU R, KANG Q, ZHANG Y, et al. Research progress of AlGaN-based deep ultraviolet light-emitting diodes[J]. Micromachines, 2023, 14(4): 844.

[2] [2] GAO X, YANG J, HE J, et al. N-AlGaN free deep-ultraviolet light-emitting diode with transverse electron injection[J]. ACS photonics, 2023, 10(3): 601-608.

[3] [3] HUANG P, XIAO L, CHEN X, et al. Efficiency improvement of AlGaN-based deep ultraviolet LEDs with gradual Al-composition AlGaN conduction layer[J]. Optoelectronics letters, 2020, 16(4): 279-283.

[4] [4] TAKANO T, MINO T, SAKAI J, et al. Deep-ultraviolet light-emitting diodes with external quantum efficiency higher than 20% at 275 nm achieved by improving light-extraction efficiency[J]. Applied physics express, 2017, 10(3): 031002.

[5] [5] IIDA D, ZHUANG Z, KIRILENKO P, et al. Demonstration of low forward voltage InGaN-based red LEDs[J]. Applied physics express, 2020, 13(3): 031001.

[6] [6] LI X, PANT N, DEJONG E, et al. Carrier dynamics in blue, cyan, and green InGaN/GaN LEDs measured by small-signal electroluminescence[J]. Applied physics letters, 2023, 122: 212108.

[7] [7] GUO Q, KIRSTE R, MITA S, et al. The polarization field in Al-rich AlGaN multiple quantum wells[J]. Japanese journal of applied physics, 2019, 58: SCCC10.

[8] [8] YU H, CHEN Q, REN Z, et al. Enhanced performance of an AlGaN-based deep-ultraviolet LED having graded quantum well structure[J]. IEEE photonics journal, 2019, 11(4): 8201006.

[9] [9] PENG K, LAI S, SHEN M, et al. AlGaN-based deep-ultraviolet light-emitting diodes with varied thickness of sidewall passivation via atomic layer deposition[J]. IEEE transactions on electron devices, 2023, 70(10): 5727-5731.

[10] [10] QIAN Y, LIAO Z, LV Z, et al. Enhanced performance of 275-nm AlGaN-based deep-ultraviolet LEDs via internal-roughed sapphire and SiO2-antireflection film[J]. Optics letters, 2023, 48(4): 1072-1075.

[11] [11] YUE W, LIU R, LI P, et al. Power enhancement of 265 nm DUV-LED flip-chip by HVPE-AlN high-temperature annealing[J]. Micromachines, 2023, 14(2): 467.

[12] [12] SHARIF M N, KHAN M A, WALI Q, et al. Tunnelling assisted by Si-doped n-AlGaN layer on the p-side of 254 nm DUV LED[J]. Optical and quantum electronics, 2023, 55(9): 785.

[13] [13] SUN X, LIU J, HUANG Y, et al. Improved external quantum efficiency of deep UV LEDs with an ultra-thin AlGaN last quantum barrier by controlling the desorption-kinetics process[J]. Applied physics express, 2023, 16(11): 111004.

[14] [14] IVANOV A E, TALNISHNIKH N A, CHERNYAKOV A E, et al. Current and temperature dependences of optical characteristics of powerful deep UV AlGaN LED (=270 nm)[J]. Physics and mathematics, 2023, 16(1.3): 170-175.

[15] [15] ISHII R, YOSHIKAWA A, NAGASE K, et al. Temperature-dependent electroluminescence study on 265-nm AlGaN-based deep-ultraviolet light-emitting diodes grown on AlN substrates[J]. AIP advances, 2020, 10(12): 125014.

[16] [16] YAN J, WANG J, LIU N, et al. High quality AlGaN grown on a high temperature AIN template by MOCVD[J]. Journal of semiconductors, 2009, 30(10): 103001.

[17] [17] LEE S R, WEST A M, ALLERMAN A A, et al. Effect of threading dislocations on the Bragg peak widths of GaN, AlGaN, and AlN heterolayers[J]. Applied physics letters, 2005, 86: 241904.

[18] [18] AJIA I A, EDWARDS P R, LIU Z, et al. Excitonic localization in AlN-rich AlxGa1−xN/AlyGa1−yN multi-quantum-well grain boundaries[J]. Applied physics letters, 2014, 105: 122111.

[19] [19] TAMULAITIS G, MICKEVIIUS J, KAZLAUSKAS K, et al. Efficiency droop in high-Al-content Al-GaN/AlGaN quantum wells[J]. Physica status solidi C, 2011, 8(7): 2130-2132.

[20] [20] WANG H, JI Z, QU S, et al. Influence of excitation power and temperature on photoluminescence in In-GaN/GaN multiple quantum wells[J]. Optics express, 2012, 20(4): 3932-3940.

[21] [21] CAI L, ZHANG B, LIN H, et al. Effect of barrier thickness on photoelectric properties of InGaN/GaN asymmetric multiple-quantum-well structure light-emitting diode[J]. AIP advances, 2022, 12(6): 065007.

[22] [22] LI L, MIYACHI Y, MIYOSHI M, et al. Enhanced emission efficiency of deep ultraviolet light-emitting AlGaN multiple quantum wells grown on an n-AlGaN underlying layer[J]. IEEE photonics journal, 2016, 8(5): 1601710.

[23] [23] CHEN S, LI Y, TIAN W, et al. Numerical analysis on the effects of multi-quantum last barriers in Al-GaN-based ultraviolet light-emitting diodes[J]. Applied physics A, 2015, 118: 1357-1363.

[24] [24] LI L, MIYACHI Y, MIYOSHI M, et al. Ultrathin inserted AlGaN/InAlN heterojunction for performance improvement in AlGaN-based deep ultraviolet light-emitting diodes[J]. Applied physics express, 2019, 12(1): 011010.