Year 2023,
, 51 - 64, 29.03.2023
İrem Alp
,
Bilgehan Barış Öner
,
Esra Eroğlu
References
- [1]Shur, M., (2021), Emerging applications of deep ultraviolet light emitting diodes, in UV and Higher Energy Photonics: From Materials to Applications 2021 Proceedings, International Society for Optics and Photonics, 11801, 1180105.
- [2] Li, J., Gao, N., Cai, D., Lin, W., Huang, K., Li, S., and Kang, J., (2021), Multiple fields manipulation on nitride material structures in ultraviolet light-emitting diodes, Light: Science & Applications, 10, 1-20.
- [3] Raeiszadeh, M. and Adeli, B., (2020), A critical review on ultraviolet disinfection systems against COVID-19 outbreak: Applicability, validation, and safety considerations, ACS Photonics, 7, 2941-2951.
- [4] Takano, T., Mino, T., Sakai, J., Noguchi, N., Tsubaki, K., and Hirayama, H., (2017), Deep-ultraviolet light-emitting diodes with external quantum efficiency higher than 20% at 275 nm achieved by improving light-extraction efficiency, Applied Physics Express, 10, 031002.
- [5] Chang, J.C., Ossoff, S.F., Lobe, D.C., Dorfman, M.H., Dumais, C.M., Qualls, R.G., and Johnson, J.D., (1985), UV inactivation of pathogenic and indicator microorganisms, Applied and environmental microbiology, 49, 1361-1365.
- [6] Kowalski, W., (2009), UVGI disinfection theory, in Ultraviolet germicidal irradiation handbook, Springer, Berlin, Heidelberg, 17-50.
- [7] Zollner, C.J., DenBaars, S.P., Speck, J., and Nakamura, S., (2021), Germicidal ultraviolet LEDs: a review of applications and semiconductor technologies, Semiconductor Science and Technology, 36, 123001.
- [8] SaifAddin, B.K., Almogbel, A.S., Zollner, C.J., Wu, F., Bonef, B., Iza, M., ... and Speck, J.S., (2020), AlGaN deep-ultraviolet light-emitting diodes grown on SiC substrates, ACS Photonics, 7, 554-561.
- [9] Lui, G.Y., Roser, D., Corkish, R., Ashbolt, N.J., and Stuetz, R., (2016), Point-of-use water disinfection using ultraviolet and visible light-emitting diodes, Science of the Total Environment, 553, 626-635.
- [10] Song, K., Mohseni, M., and Taghipour, F., (2016), Application of ultraviolet light-emitting diodes (UV-LEDs) for water disinfection: A review, Water Research, 94, 341-349.
- [11] Kheyrandish, A., Mohseni, M., and Taghipour, F., (2017), Development of a method for the characterization and operation of UV-LED for water treatment, Water Research, 122, 570-579.
- [12] Vilhunen, S., Särkkä, H., and Sillanpää, M., (2009), Ultraviolet light-emitting diodes in water disinfection, Environmental Science and Pollution Research, 16, 439-442.
- [13] Nakamura, S., (1998), The roles of structural imperfections in InGaN-based blue light-emitting diodes and laser diodes, Science, 281, 956-961.
- [14] Kneissl, M., Seong, T.Y., Han, J., and Amano, H., (2019), The emergence and prospects of deep-ultraviolet light-emitting diode technologies, Nature Photonics, 13, 233-244.
- [15] Amano, H., Collazo, R., De Santi, C., Einfeldt, S., Funato, M., Glaab, J., ... and Zhang, Y., (2020), The 2020 UV emitter roadmap, Journal of Physics D: Applied Physics, 53, 503001.
- [16] Demir, İ., (2018), Growth temperature dependency of high Al content AlGaN epilayers on AlN/Al2O3 templates, Cumhuriyet Science Journal, 39, 728-733.
- [17] Park, T.H., Lee, T.H., and Kim, T.G., (2019), Al2O3/AlN/Al-based backside diffuse reflector for high-brightness 370-nm AlGaN ultraviolet light-emitting diodes, Journal of Alloys and Compounds, 776, 1009-1015.
- [18] Lim, S.H., Shin, E.J., Lee, H.S., Han, S.K., Le, D.D., and Hong, S.K., (2019), Effects of growth rate and III/V ratio on properties of AlN films grown on c-plane sapphire substrates by plasma-assisted molecular beam epitaxy, Korean Journal of Materials Research, 29, 579-585.
- [19] Nagasawa, Y. and Hirano, A., (2018), A review of AlGaN-based deep-ultraviolet light-emitting diodes on sapphire, Applied Sciences, 8, 1264.
- [20] Park, K.W. and Yun, Y.H., (2020), Effects of AlN buffer layer on optical properties of epitaxial layer structure deposited on patterned sapphire substrate, Journal of the Korean Crystal Growth and Crystal Technology, 30, 1-6.
- [21] Ren, Z., Lu, Y., Yao, H.-H., Sun, H., Liao, C.-H., Dai, J., …, and Li, X., (2019), III-nitride deep UV LED without electron blocking layer, IEEE Photonics Journal, 11, 1-11.
- [22] Acharya, J., Venkateshh, S., and Ghosh, K., (2021), Engineering the Active Region to Enhance the IQE by ~8% in AlGaN/GaN based UV-C LED, in 2021 International Conference on Numerical Simulation of Optoelectronic Devices Proceedings, Institute of Electrical and Electronics Engineers, NUSOD 2021, 69-70.
- [23] Gao, N., Chen, J., Feng, X., Lu, S., Lin, W., Li, J., Chen, H., Huang, K., and Kang, J., (2021), Strain engineering of digitally alloyed AlN/GaN nanorods for far-UVC emission as short as 220 nm, Optical Materials Express, 11, 1282-1291.
- [24] Peng, Y., Guo, X., Liang, R., Cheng, H., and Chen, M., (2017), Enhanced light extraction from DUV-LEDs by AlN-doped fluoropolymer encapsulation, IEEE Photonics Technology Letters, 29, 1151-1154.
- [25] Liu, C., Melanson, B., and Zhang, J., (2020), AlGaN-Delta-GaN quantum well for DUV LEDs, Photonics, 7, 87.
- [26] Zhuang, Z., Iida, D., and Ohkawa, K., (2020), Enhanced performance of N-polar AlGaN-based deep-ultraviolet light-emitting diodes, Optics Express, 28, 30423-30431.
- [27] Tomson, R., Uhlin, F., and Fridolin, I., (2014), Urea Rebound Assessment Based on UV Absorbance in Spent Dialysate, Asaio Journal, 60, 459-465.
- [28] Hirayama, H., Kashima, Y., Matsuura, E., Maeda, N., and Jo, M., (2021), Progress on high-power UVC LEDs by increasing light-extraction efficiency, in Light-Emitting Devices, Materials, and Applications XXV, International Society for Optics and Photonics, 11706, 117060G.
- [29] Jain, B., Velpula, R.T., Patel, M., Sadaf, S.Md., and Nguyen, H.P.T., (2021), Improved performance of electron blocking layer free AlGaN deep ultraviolet light-emitting diodes using graded staircase barriers, Micromachines, 12, 334.
- [30] Zhang, N., Xu, F.J., Lang, J., Wang, L.B., Wang, J.M., Sun, Y.H., ... and Shen, B., (2021), Improved light extraction efficiency of AlGaN deep-ultraviolet light emitting diodes combining Ag-nanodots/Al reflective electrode with highly transparent p-type layer, Optics Express, 29, 2394-2401.
- [31] Itokazu, Y., Kuwaba, S., Jo, M., Kamata, N., and Hirayama, H., (2019), Influence of the nucleation conditions on the quality of AlN layers with high-temperature annealing and regrowth processes, Japanese Journal of Applied Physics, 58, SC1056.
- [32] Shin, W., Pandey, A., Liu, X., Sun, Y., and Mi, Z., (2019), Photonic crystal tunnel junction deep ultraviolet light emitting diodes with enhanced light extraction efficiency, Optics Express, 27, 38413-38420.
- [33] Moe, C.G., Sugiyama, S., Kasai, J., Grandusky, J.R., and Schowalter, L.J., (2018), AlGaN Light‐Emitting Diodes on AlN Substrates Emitting at 230 nm, Physica Status Solidi (a), 215, 1700660.
- [34] Chen, X. and Wu, Y.R., (2015), Numerical study of current spreading and light extraction in deep UV light-emitting diode, in Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XIX, International Society for Optics and Photonics, 9383, 93830Q.
- [35] Bhattacharyya, A., Moustakas, T.D., Zhou, L., Smith, D.J., and Hug, W., (2009), Deep ultraviolet emitting AlGaN quantum wells with high internal quantum efficiency, Applied Physics Letters, 94, 181907.
- [36] Rudinsky, M.E. and Karpov, S.Y., (2020), Radiative and Auger recombination constants and internal quantum efficiency of (0001) AlGaN deep‐UV light‐emitting diode structures, Physica Status Solidi (a), 217, 1900878.
- [37] Bryan, Z., Bryan, I., Xie, J., Mita, S., Sitar, Z., and Collazo, R., (2015), High internal quantum efficiency in AlGaN multiple quantum wells grown on bulk AlN substrates, Applied Physics Letters, 106, 142107.
- [38] Lobo-Ploch, N., Mehnke, F., Sulmoni, L., Cho, H.K., Guttmann, M., Glaab, J., … and Kneissl, M., (2020), Milliwatt power 233 nm AlGaN-based deep UV-LEDs on sapphire substrates, Applied Physics Letters, 117, 111102.
- [39] Murotani, H., Tanabe, R., Hisanaga, K., Hamada, A., Beppu, K., Maeda, N., ... and Yamada, Y., (2020), High internal quantum efficiency and optically pumped stimulated emission in AlGaN-based UV-C multiple quantum wells, Applied Physics Letters, 117, 162106.
- [40] Shim, J.I., Han, D.P., Oh, C.H., Jung, H., and Shin, D.S., (2018), Measuring the internal quantum efficiency of light-emitting diodes at an arbitrary temperature, IEEE Journal of Quantum Electronics, 54, 1-6.
- [41] Hirayama, H., Fujikawa, S., Noguchi, N., Norimatsu, J., Takano, T., Tsubaki, K., and Kamata, N., (2009), 222–282 nm AlGaN and InAlGaN‐based deep‐UV LEDs fabricated on high‐quality AlN on sapphire, Physica Status Solidi (a), 206, 1176-1182.
- [42] Wang, T.Y., Tasi, C.T., Lin, C.F., and Wuu, D.S., (2017), 85% internal quantum efficiency of 280-nm AlGaN multiple quantum wells by defect engineering, Scientific Reports, 7, 1-8.
- [43] Hao, G.D., Tamari, N., Obata, T., Kinoshita, T., and Inoue, S.I., (2017), Electrical determination of current injection and internal quantum efficiencies in AlGaN-based deep-ultraviolet light-emitting diodes, Optics Express, 25, A639-A648.
- [44] Dong, P., Yan, J., Zhang, Y., Wang, J., Zeng, J., Geng, C., ... and Li, J., (2014), AlGaN-based deep ultraviolet light-emitting diodes grown on nano-patterned sapphire substrates with significant improvement in internal quantum efficiency, Journal of Crystal Growth, 395, 9-13.
- [45] Guttmann, M., Susilo, A., Sulmoni, L., Susilo, N., Ziffer, E., Wernicke, T., and Kneissl, M., (2021), Light extraction efficiency and internal quantum efficiency of fully UVC-transparent AlGaN based LEDs, Journal of Physics D: Applied Physics, 54, 335101.
- [46] Trellakis, A., Zibold, T., Andlauer, T., Birner, S., Smith, R.K., Morschl, R., and Vogl, P., (2006), The 3D nanometer device project nextnano: Concepts, methods, results, Journal of Computational Electronics, 5, 285–289.
- [47] Birner, S., Zibold, T., Andlauer, T., Kubis, T., Sabathil, M., Trellakis, A., and Vogl, P., (2007), Nextnano: general purpose 3-D simulations, IEEE Transactions on Electron Devices, 54, 2137-2142.
- [48] Dmitriev, A. and Oruzheinikov, A., (1999), The rate of radiative recombination in the nitride semiconductors and alloys, Journal of Applied Physics, 86, 3241-3246.
- [49] Nippert, F., Tollabi Mazraehno, M., Davies, M.J., Hoffmann, M.P., Lugauer, H.J., Kure, T., ... and Wagner, M.R., (2018), Auger recombination in AlGaN quantum wells for UV light-emitting diodes, Applied Physics Letters, 113, 071107.
- [50] Hirayama, H., Fujikawa, S., and Kamata, N., (2015), Recent progress in AlGaN‐based deep‐UV LEDs, Electronics and Communications in Japan, 98, 1-8.
- [51] Yu, J., Hao, Z., Li, L., Wang, L., Luo, Y., Wang, J., and Li, H., (2017), Influence of dislocation density on internal quantum efficiency of GaN-based semiconductors, AIP Advances, 7, 035321.
- [52] A. F. Oskooi, D. Roundy, M. Ibanescu, P. Ber-mel, J. D. Joannopoulos, and S. G. Johnson (2010), Meep: A flexible free-software package for electromagnetic simulations by the FDTD method, Computer Physics Communications, 181, 687-702.
285 nm AlGaN-BASED DEEP-ULTRAVIOLET LED WITH HIGH INTERNAL QUANTUM EFFICIENCY: COMPUTATIONAL DESIGN
Year 2023,
, 51 - 64, 29.03.2023
İrem Alp
,
Bilgehan Barış Öner
,
Esra Eroğlu
Abstract
In this paper, the systematic computational design process of AlGaN-based multiple quantum-well (QW) deep-ultraviolet (DUV) light-emitting diode (LED) grown on sapphire (Al2O3) substrate was investigated. An optimization was held to increase internal quantum efficiency (IQE) handling the LED parameters such as doping percentage of the n- and the p-type layers of these devices. The structure parameters of the best design were determined through a customized genetic algorithm integrated into the nanostructure quantum electronic simulation (nextnano). As a determining factor, IQE was obtained to be 24% for the devised 285 nm LED. It has been demonstrated that this result can be increased up to a remarkably high value of 70% by a low threading dislocation density (TDD) and reduced Auger recombination. In addition, the operation input power and potential difference were successfully kept below 0.1 W/mm2 and 5.05 V, respectively.
Thanks
The nanostructure quantum electronic simulation nextnano has been employed in the first optimization step on internal quantum efficiency. We would like to thank Dr. Stefan BIRNER and the team for their understanding and contribution in using the package.
References
- [1]Shur, M., (2021), Emerging applications of deep ultraviolet light emitting diodes, in UV and Higher Energy Photonics: From Materials to Applications 2021 Proceedings, International Society for Optics and Photonics, 11801, 1180105.
- [2] Li, J., Gao, N., Cai, D., Lin, W., Huang, K., Li, S., and Kang, J., (2021), Multiple fields manipulation on nitride material structures in ultraviolet light-emitting diodes, Light: Science & Applications, 10, 1-20.
- [3] Raeiszadeh, M. and Adeli, B., (2020), A critical review on ultraviolet disinfection systems against COVID-19 outbreak: Applicability, validation, and safety considerations, ACS Photonics, 7, 2941-2951.
- [4] Takano, T., Mino, T., Sakai, J., Noguchi, N., Tsubaki, K., and Hirayama, H., (2017), Deep-ultraviolet light-emitting diodes with external quantum efficiency higher than 20% at 275 nm achieved by improving light-extraction efficiency, Applied Physics Express, 10, 031002.
- [5] Chang, J.C., Ossoff, S.F., Lobe, D.C., Dorfman, M.H., Dumais, C.M., Qualls, R.G., and Johnson, J.D., (1985), UV inactivation of pathogenic and indicator microorganisms, Applied and environmental microbiology, 49, 1361-1365.
- [6] Kowalski, W., (2009), UVGI disinfection theory, in Ultraviolet germicidal irradiation handbook, Springer, Berlin, Heidelberg, 17-50.
- [7] Zollner, C.J., DenBaars, S.P., Speck, J., and Nakamura, S., (2021), Germicidal ultraviolet LEDs: a review of applications and semiconductor technologies, Semiconductor Science and Technology, 36, 123001.
- [8] SaifAddin, B.K., Almogbel, A.S., Zollner, C.J., Wu, F., Bonef, B., Iza, M., ... and Speck, J.S., (2020), AlGaN deep-ultraviolet light-emitting diodes grown on SiC substrates, ACS Photonics, 7, 554-561.
- [9] Lui, G.Y., Roser, D., Corkish, R., Ashbolt, N.J., and Stuetz, R., (2016), Point-of-use water disinfection using ultraviolet and visible light-emitting diodes, Science of the Total Environment, 553, 626-635.
- [10] Song, K., Mohseni, M., and Taghipour, F., (2016), Application of ultraviolet light-emitting diodes (UV-LEDs) for water disinfection: A review, Water Research, 94, 341-349.
- [11] Kheyrandish, A., Mohseni, M., and Taghipour, F., (2017), Development of a method for the characterization and operation of UV-LED for water treatment, Water Research, 122, 570-579.
- [12] Vilhunen, S., Särkkä, H., and Sillanpää, M., (2009), Ultraviolet light-emitting diodes in water disinfection, Environmental Science and Pollution Research, 16, 439-442.
- [13] Nakamura, S., (1998), The roles of structural imperfections in InGaN-based blue light-emitting diodes and laser diodes, Science, 281, 956-961.
- [14] Kneissl, M., Seong, T.Y., Han, J., and Amano, H., (2019), The emergence and prospects of deep-ultraviolet light-emitting diode technologies, Nature Photonics, 13, 233-244.
- [15] Amano, H., Collazo, R., De Santi, C., Einfeldt, S., Funato, M., Glaab, J., ... and Zhang, Y., (2020), The 2020 UV emitter roadmap, Journal of Physics D: Applied Physics, 53, 503001.
- [16] Demir, İ., (2018), Growth temperature dependency of high Al content AlGaN epilayers on AlN/Al2O3 templates, Cumhuriyet Science Journal, 39, 728-733.
- [17] Park, T.H., Lee, T.H., and Kim, T.G., (2019), Al2O3/AlN/Al-based backside diffuse reflector for high-brightness 370-nm AlGaN ultraviolet light-emitting diodes, Journal of Alloys and Compounds, 776, 1009-1015.
- [18] Lim, S.H., Shin, E.J., Lee, H.S., Han, S.K., Le, D.D., and Hong, S.K., (2019), Effects of growth rate and III/V ratio on properties of AlN films grown on c-plane sapphire substrates by plasma-assisted molecular beam epitaxy, Korean Journal of Materials Research, 29, 579-585.
- [19] Nagasawa, Y. and Hirano, A., (2018), A review of AlGaN-based deep-ultraviolet light-emitting diodes on sapphire, Applied Sciences, 8, 1264.
- [20] Park, K.W. and Yun, Y.H., (2020), Effects of AlN buffer layer on optical properties of epitaxial layer structure deposited on patterned sapphire substrate, Journal of the Korean Crystal Growth and Crystal Technology, 30, 1-6.
- [21] Ren, Z., Lu, Y., Yao, H.-H., Sun, H., Liao, C.-H., Dai, J., …, and Li, X., (2019), III-nitride deep UV LED without electron blocking layer, IEEE Photonics Journal, 11, 1-11.
- [22] Acharya, J., Venkateshh, S., and Ghosh, K., (2021), Engineering the Active Region to Enhance the IQE by ~8% in AlGaN/GaN based UV-C LED, in 2021 International Conference on Numerical Simulation of Optoelectronic Devices Proceedings, Institute of Electrical and Electronics Engineers, NUSOD 2021, 69-70.
- [23] Gao, N., Chen, J., Feng, X., Lu, S., Lin, W., Li, J., Chen, H., Huang, K., and Kang, J., (2021), Strain engineering of digitally alloyed AlN/GaN nanorods for far-UVC emission as short as 220 nm, Optical Materials Express, 11, 1282-1291.
- [24] Peng, Y., Guo, X., Liang, R., Cheng, H., and Chen, M., (2017), Enhanced light extraction from DUV-LEDs by AlN-doped fluoropolymer encapsulation, IEEE Photonics Technology Letters, 29, 1151-1154.
- [25] Liu, C., Melanson, B., and Zhang, J., (2020), AlGaN-Delta-GaN quantum well for DUV LEDs, Photonics, 7, 87.
- [26] Zhuang, Z., Iida, D., and Ohkawa, K., (2020), Enhanced performance of N-polar AlGaN-based deep-ultraviolet light-emitting diodes, Optics Express, 28, 30423-30431.
- [27] Tomson, R., Uhlin, F., and Fridolin, I., (2014), Urea Rebound Assessment Based on UV Absorbance in Spent Dialysate, Asaio Journal, 60, 459-465.
- [28] Hirayama, H., Kashima, Y., Matsuura, E., Maeda, N., and Jo, M., (2021), Progress on high-power UVC LEDs by increasing light-extraction efficiency, in Light-Emitting Devices, Materials, and Applications XXV, International Society for Optics and Photonics, 11706, 117060G.
- [29] Jain, B., Velpula, R.T., Patel, M., Sadaf, S.Md., and Nguyen, H.P.T., (2021), Improved performance of electron blocking layer free AlGaN deep ultraviolet light-emitting diodes using graded staircase barriers, Micromachines, 12, 334.
- [30] Zhang, N., Xu, F.J., Lang, J., Wang, L.B., Wang, J.M., Sun, Y.H., ... and Shen, B., (2021), Improved light extraction efficiency of AlGaN deep-ultraviolet light emitting diodes combining Ag-nanodots/Al reflective electrode with highly transparent p-type layer, Optics Express, 29, 2394-2401.
- [31] Itokazu, Y., Kuwaba, S., Jo, M., Kamata, N., and Hirayama, H., (2019), Influence of the nucleation conditions on the quality of AlN layers with high-temperature annealing and regrowth processes, Japanese Journal of Applied Physics, 58, SC1056.
- [32] Shin, W., Pandey, A., Liu, X., Sun, Y., and Mi, Z., (2019), Photonic crystal tunnel junction deep ultraviolet light emitting diodes with enhanced light extraction efficiency, Optics Express, 27, 38413-38420.
- [33] Moe, C.G., Sugiyama, S., Kasai, J., Grandusky, J.R., and Schowalter, L.J., (2018), AlGaN Light‐Emitting Diodes on AlN Substrates Emitting at 230 nm, Physica Status Solidi (a), 215, 1700660.
- [34] Chen, X. and Wu, Y.R., (2015), Numerical study of current spreading and light extraction in deep UV light-emitting diode, in Light-Emitting Diodes: Materials, Devices, and Applications for Solid State Lighting XIX, International Society for Optics and Photonics, 9383, 93830Q.
- [35] Bhattacharyya, A., Moustakas, T.D., Zhou, L., Smith, D.J., and Hug, W., (2009), Deep ultraviolet emitting AlGaN quantum wells with high internal quantum efficiency, Applied Physics Letters, 94, 181907.
- [36] Rudinsky, M.E. and Karpov, S.Y., (2020), Radiative and Auger recombination constants and internal quantum efficiency of (0001) AlGaN deep‐UV light‐emitting diode structures, Physica Status Solidi (a), 217, 1900878.
- [37] Bryan, Z., Bryan, I., Xie, J., Mita, S., Sitar, Z., and Collazo, R., (2015), High internal quantum efficiency in AlGaN multiple quantum wells grown on bulk AlN substrates, Applied Physics Letters, 106, 142107.
- [38] Lobo-Ploch, N., Mehnke, F., Sulmoni, L., Cho, H.K., Guttmann, M., Glaab, J., … and Kneissl, M., (2020), Milliwatt power 233 nm AlGaN-based deep UV-LEDs on sapphire substrates, Applied Physics Letters, 117, 111102.
- [39] Murotani, H., Tanabe, R., Hisanaga, K., Hamada, A., Beppu, K., Maeda, N., ... and Yamada, Y., (2020), High internal quantum efficiency and optically pumped stimulated emission in AlGaN-based UV-C multiple quantum wells, Applied Physics Letters, 117, 162106.
- [40] Shim, J.I., Han, D.P., Oh, C.H., Jung, H., and Shin, D.S., (2018), Measuring the internal quantum efficiency of light-emitting diodes at an arbitrary temperature, IEEE Journal of Quantum Electronics, 54, 1-6.
- [41] Hirayama, H., Fujikawa, S., Noguchi, N., Norimatsu, J., Takano, T., Tsubaki, K., and Kamata, N., (2009), 222–282 nm AlGaN and InAlGaN‐based deep‐UV LEDs fabricated on high‐quality AlN on sapphire, Physica Status Solidi (a), 206, 1176-1182.
- [42] Wang, T.Y., Tasi, C.T., Lin, C.F., and Wuu, D.S., (2017), 85% internal quantum efficiency of 280-nm AlGaN multiple quantum wells by defect engineering, Scientific Reports, 7, 1-8.
- [43] Hao, G.D., Tamari, N., Obata, T., Kinoshita, T., and Inoue, S.I., (2017), Electrical determination of current injection and internal quantum efficiencies in AlGaN-based deep-ultraviolet light-emitting diodes, Optics Express, 25, A639-A648.
- [44] Dong, P., Yan, J., Zhang, Y., Wang, J., Zeng, J., Geng, C., ... and Li, J., (2014), AlGaN-based deep ultraviolet light-emitting diodes grown on nano-patterned sapphire substrates with significant improvement in internal quantum efficiency, Journal of Crystal Growth, 395, 9-13.
- [45] Guttmann, M., Susilo, A., Sulmoni, L., Susilo, N., Ziffer, E., Wernicke, T., and Kneissl, M., (2021), Light extraction efficiency and internal quantum efficiency of fully UVC-transparent AlGaN based LEDs, Journal of Physics D: Applied Physics, 54, 335101.
- [46] Trellakis, A., Zibold, T., Andlauer, T., Birner, S., Smith, R.K., Morschl, R., and Vogl, P., (2006), The 3D nanometer device project nextnano: Concepts, methods, results, Journal of Computational Electronics, 5, 285–289.
- [47] Birner, S., Zibold, T., Andlauer, T., Kubis, T., Sabathil, M., Trellakis, A., and Vogl, P., (2007), Nextnano: general purpose 3-D simulations, IEEE Transactions on Electron Devices, 54, 2137-2142.
- [48] Dmitriev, A. and Oruzheinikov, A., (1999), The rate of radiative recombination in the nitride semiconductors and alloys, Journal of Applied Physics, 86, 3241-3246.
- [49] Nippert, F., Tollabi Mazraehno, M., Davies, M.J., Hoffmann, M.P., Lugauer, H.J., Kure, T., ... and Wagner, M.R., (2018), Auger recombination in AlGaN quantum wells for UV light-emitting diodes, Applied Physics Letters, 113, 071107.
- [50] Hirayama, H., Fujikawa, S., and Kamata, N., (2015), Recent progress in AlGaN‐based deep‐UV LEDs, Electronics and Communications in Japan, 98, 1-8.
- [51] Yu, J., Hao, Z., Li, L., Wang, L., Luo, Y., Wang, J., and Li, H., (2017), Influence of dislocation density on internal quantum efficiency of GaN-based semiconductors, AIP Advances, 7, 035321.
- [52] A. F. Oskooi, D. Roundy, M. Ibanescu, P. Ber-mel, J. D. Joannopoulos, and S. G. Johnson (2010), Meep: A flexible free-software package for electromagnetic simulations by the FDTD method, Computer Physics Communications, 181, 687-702.