J. Semicond. > 2022, Volume 43 > Issue 7 > 072301

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Watts-level ultraviolet-C LED integrated light sources for efficient surface and air sterilization

Wei Luo1, Tai Li2, Yongde Li1, Houjin Wang1, Ye Yuan1, Shangfeng Liu2, Weiyun Wang1, Qi Wang3, Junjie Kang1, and Xinqiang Wang1, 2,

+ Author Affiliations

 Corresponding author: Junjie Kang, kangjunjie@sslab.org.cn; Xinqiang Wang, wangshi@pku.edu.cn

DOI: 10.1088/1674-4926/43/7/072301

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Abstract: With the epidemic of the coronavirus disease (COVID-19) infection, AlGaN-based ultraviolet-C light emitting diodes (UVC-LEDs) have attracted widespread attention for their sterilization application. However, the sterilization characters of high power integrated light sources (ILSs) haven’t been widely investigated before utilizing in public sanitary security. In this work, by integrating up to 195 UVC-LED chips, high power UVC-LED ILSs with a light output power (LOP) of 1.88 W were demonstrated. The UVC-LED ILSs were verified to have efficient and rapid sterilization capability, which have achieved more than 99.9% inactivation rate of several common pathogenic microorganisms within 1 s. In addition, the corresponding air sterilization module based on them was also demonstrated to kill more than 97% of Staphylococcus albus in the air of 20 m3 confined room within 30 min. This work demonstrates excellent sterilization ability of UVC-LED ILSs with high LOP, revealing great potential of UVC-LEDs in sterilization applications in the future.

Key words: ultraviolet-C LEDintegrated light sourcesurface sterilizationair sterilization



[1]
Abbasi R, Jain R, Nelson K, et al. Polymeric films containing sodium chlorite that release disinfectant gas upon activation with UV light. Adv Funct Mater, 2019, 29(7), 1804851 doi: 10.1002/adfm.201804851
[2]
Ogata N, Sakasegawa M, Miura T, et al. Inactivation of airborne bacteria and viruses using extremely low concentrations of chlorine dioxide gas. Pharmacology, 2016, 97(5/6), 301 doi: 10.1159/000444503
[3]
Rauth A M. The physical state of viral nucleic acid and the sensitivity of viruses to ultraviolet light. Biophys J, 1965, 5(3), 257 doi: 10.1016/S0006-3495(65)86715-7
[4]
Beck S E, Wright H B, Hargy T M, et al. Action spectra for validation of pathogen disinfection in medium-pressure ultraviolet (UV) systems. Water Res, 2015, 70, 27 doi: 10.1016/j.watres.2014.11.028
[5]
Santos A L, Moreirinha C, Lopes D, et al. Effects of UV radiation on the lipids and proteins of bacteria studied by mid-infrared spectroscopy. Environ Sci Technol, 2013, 47(12), 6306 doi: 10.1021/es400660g
[6]
Hijnen W, Beerendonk E, Medema G J. Inactivation credit of UV radiation for viruses, bacteria and protozoan (oo) cysts in water: a review. Water Res, 2006, 40(1), 3 doi: 10.1016/j.watres.2005.10.030
[7]
Sarigiannis D, Karakitsios S, Antonakopoulou M, et al. Exposure analysis of accidental release of mercury from compact fluorescent lamps (CFLs). Sci Total Environ, 2012, 435, 306 doi: 10.1016/j.scitotenv.2012.07.026
[8]
Schalk S, Adam V, Arnold E, et al. UV-lamps for disinfection and advanced oxidation-lamp types, technologies and applications. IUVA News, 2006, 8(1), 32
[9]
da Silveira Petruci J F, Fortes P R, Kokoric V, et al. Real-time monitoring of ozone in air using substrate-integrated hollow waveguide mid-infrared sensors. Sci Reports, 2013, 3(1), 1 doi: 10.1038/srep03174
[10]
Hirayama H, Maeda N, Fujikawa S, et al. Recent progress and future prospects of AlGaN-based high-efficiency deep-ultraviolet light-emitting diodes. Jpn J Appl Phys, 2014, 53(10), 100209 doi: 10.7567/JJAP.53.100209
[11]
Li D, Jiang K, Sun X, et al. AlGaN photonics: recent advances in materials and ultraviolet devices. Adv Opt Photonics, 2018, 10(1), 43 doi: 10.1364/AOP.10.000043
[12]
Kneissl M, Seong T Y, Han J, et al. The emergence and prospects of deep-ultraviolet light-emitting diode technologies. Nat Photonics, 2019, 13(4), 233 doi: 10.1038/s41566-019-0359-9
[13]
Taniyasu Y, Kasu M, Makimoto T. An aluminium nitride light-emitting diode with a wavelength of 210 nanometres. Nature, 2006, 441(7091), 325 doi: 10.1038/nature04760
[14]
Khan A, Balakrishnan K, Katona T. Ultraviolet light-emitting diodes based on group three nitrides. Nat Photonics, 2008, 2(2), 77 doi: 10.1038/nphoton.2007.293
[15]
Nagasawa Y, Hirano A. A review of AlGaN-based deep-ultraviolet light-emitting diodes on sapphire. Appl Sci, 2018, 8(8), 1264 doi: 10.3390/app8081264
[16]
Simon J, Protasenko V, Lian C, et al. Polarization-induced hole doping in wide–band-gap uniaxial semiconductor heterostructures. Science, 2010, 327(5961), 60 doi: 10.1126/science.1183226
[17]
Zhang L, Ding K, Yan J, et al. Three-dimensional hole gas induced by polarization in (0001)-oriented metal-face III-nitride structure. Appl Phys Lett, 2010, 97(6), 062103 doi: 10.1063/1.3478556
[18]
Ryu H Y, Choi I G, Choi H S, et al. Investigation of light extraction efficiency in AlGaN deep-ultraviolet light-emitting diodes. Appl Phys Express, 2013, 6(6), 062101 doi: 10.7567/APEX.6.062101
[19]
Li Y, Wang C, Zhang Y, et al. Analysis of TM/TE mode enhancement and droop reduction by a nanoporous n-AlGaN underlayer in a 290 nm UV-LED. Photonics Res, 2020, 8(6), 806 doi: 10.1364/PRJ.387607
[20]
Bowker C, Sain A, Shatalov M, et al. Microbial UV fluence-response assessment using a novel UV-LED collimated beam system. Water Res, 2011, 45(5), 2011 doi: 10.1016/j.watres.2010.12.005
[21]
Bolton J R, Linden K G. Standardization of methods for fluence (UV dose) determination in bench-scale UV experiments. J Environ Eng, 2003, 129(3), 209 doi: 10.1061/(ASCE)0733-9372(2003)129:3(209)
[22]
Suzuki A, Emoto A, Shirai A, et al. Ultraviolet light-emitting diode (UV-LED) sterilization of citrus bacterial canker disease targeted for effective decontamination of citrus sudachi fruit. Biocontrol Sci, 2022, 27(1), 1 doi: 10.4265/bio.27.1
[23]
Lee Y W, Yoon H D, Park J H, et al. Application of 265-nm UVC LED lighting to sterilization of typical gram negative and positive bacteria. J Korean Physl Soc, 2018, 72(10), 1174 doi: 10.3938/jkps.72.1174
[24]
Huang S Y, Lin J C, Huang X Q, et al. Large-area 280 nm LED flexible sterilization light source with improved thermal performance. Optik, 2021, 248, 168109 doi: 10.1016/j.ijleo.2021.168109
[25]
Kim B S, Youm S, Kim Y K. Sterilization of harmful microorganisms in hydroponic cultivation using an ultraviolet LED light source. Sens Mater, 2020, 32(11), 3773 doi: 10.18494/SAM.2020.2979
[26]
Nunayon S S, Zhang H, Lai A C K. Comparison of disinfection performance of UVC-LED and conventional upper-room UVGI systems. Indoor Air, 2020, 30(1), 180 doi: 10.1111/ina.12619
[27]
Liu S, Luo W, Li D, et al. Sec-eliminating the SARS-CoV-2 by AlGaN based high power deep ultraviolet light source. Adv Funct Mater, 2020, 31, 2008452 doi: 10.1002/adfm.202008452
[28]
Bormann M, Alt M, Schipper L, et al. Disinfection of SARS-CoV-2 contaminated surfaces of personal items with UVC-LED disinfection boxes. Viruses, 2021, 13(4), 598 doi: 10.3390/v13040598
[29]
Tamulaitis G, Mickevičius J, Kazlauskas K, et al. Efficiency droop in high-Al-content AlGaN/AlGaN quantum wells. Phys Status Solidi C, 2011, 8(7/8), 2130 doi: 10.1002/pssc.201000889
[30]
Yun J, Shim J I, Hirayama H. Analysis of efficiency droop in 280-nm AlGaN multiple-quantum-well light-emitting diodes based on carrier rate equation. Appl Phys Express, 2015, 8(2), 022104 doi: 10.7567/APEX.8.022104
[31]
Cho J, Schubert E F, Kim J K. Efficiency droop in light-emitting diodes: Challenges and countermeasures. Laser Photonics Rev, 2013, 7(3), 408 doi: 10.1002/lpor.201200025
[32]
Hu J, Zhang J, Zhang Y, et al. Enhanced performance of AlGaN-based deep ultraviolet light-emitting diodes with chirped superlattice electron deceleration layer. Nanoscale Res Lett, 2019, 14(1), 1 doi: 10.1186/s11671-018-2843-4
[33]
Bolton J R, Cotton C A. The ultraviolet disinfection handbook. Glacier Publishing Services, Inc., 2011
[34]
Rastogi R P, Kumar A, Tyagi M B, et al. Molecular mechanisms of ultraviolet radiation-induced DNA damage and repair. J Nucleic Acids, 2010, 90(6/7), 560 doi: 10.4061/2010/592980
Fig. 1.  (Color online) Schematic of UVC-LED ILS: (a) assembly diagram, (b) explosive diagram.

Fig. 2.  (Color online) Characterization of three UVC-LED ILSs: (a) LOP vs. current, (b) voltage vs. current, (c) WPE vs. current, (d) EL spectra.

Fig. 3.  (Color online) (a) Irradiance at different distances from the 275-nm-UVC-LED ILS under an injection current of 0.8 A. The inset shows that the reciprocal of irradiance is approximately proportional to the square of distance. (b) Irradiance distribution of the central axis of light-emitting area (x = 0 at the center of light-emitting area). (c) Temperature change with time after the 275-nm-UVC-LED ILS was turned on. The inset shows the locations for temperature measurements: p1 and p2 are the center and the edge of the quartz glass on light-emitting area, respectively, and p3 is located on AlN ceramic substrate and close to the light-emitting area. (d) Irradiance at a distance of 5 cm from the light-emitting surface of the 275-nm-UVC-LED ILS under different current injection.

Fig. 4.  Micrographs of the Microorganism Colonies of (a, d) Escherichia coli, (b, e) Staphylococcus aureus, (c, f) Candida albicans before (a, b, c) and after (d, e, f) one-second sterilization by the 275-nm-UVC-LED ILS.

Fig. 5.  (Color online) (a) Schematic diagram and (b) photo of the air sterilization module based on 275-nm-UVC-LED ILS. (c) Photo of UVC-LED array viewed from the inlet direction.

Table 1.   Sterilization effects of three UVC-LED ILSs with different light-emitting wavelengths on Staphylococcus aureus.

Test microorganismTest sampleTest conditionIrradiation intensity
(mW/cm2)
Colony counts after
test (CFU/mL)
Inactivation
rate (%)
Staphylococcus
aureus
Controlw/o irradiation1.4 × 106
275-nm-UVC-LED ILS20 cm, 0.36 A, 10 s0.504.6 × 10496.71
265-nm-UVC-LED ILS20 cm, 0.25 A, 10 s0.506.0 × 10399.57
255-nm-UVC-LED ILS20 cm, 0.58 A, 10 s0.503.4 × 10399.76
DownLoad: CSV

Table 2.   Sterilization effects of the 275-nm-UVC-LED ILS on different microorganisms.

Test microorganismTest sampleTest conditionColony counts after test (CFU/mL)Inactivation rate (%)
Escherichia coliControlw/o irradiation5.1 × 105
275-nm-UVC-LED ILS5 cm, 0.80 A, 1 s< 10> 99.99
Staphylococcus aureusControlw/o irradiation6.6 × 105
275-nm-UVC-LED ILS5 cm, 0.80 A, 1 s< 10> 99.99
Candida albicansControlw/o irradiation3.3 × 104
275-nm-UVC-LED ILS5 cm, 0.80 A, 1 s3099.90
DownLoad: CSV

Table 3.   Sterilization effects of the air sterilization module based on the 275-nm-UVC-LED ILS on Staphylococcus albus in the air of 20 m3 confined room.

Test microorganismTest groupTest time (min)Control
(w/o irradiation)
Air sterilization module
Colony count (CFU/m3)Nature inactivation rate (%)Colony count (CFU/m3)Inactivation rate (%)
Staphylococcus albus101.26 × 10517.461.18 × 10597.03
301.04 × 1052.89 × 103
201.18 × 10517.881.29 × 10597.19
300.97 × 1052.98 × 103
301.23 × 10517.891.30 × 10597.14
301.01 × 1053.05 × 103
DownLoad: CSV
[1]
Abbasi R, Jain R, Nelson K, et al. Polymeric films containing sodium chlorite that release disinfectant gas upon activation with UV light. Adv Funct Mater, 2019, 29(7), 1804851 doi: 10.1002/adfm.201804851
[2]
Ogata N, Sakasegawa M, Miura T, et al. Inactivation of airborne bacteria and viruses using extremely low concentrations of chlorine dioxide gas. Pharmacology, 2016, 97(5/6), 301 doi: 10.1159/000444503
[3]
Rauth A M. The physical state of viral nucleic acid and the sensitivity of viruses to ultraviolet light. Biophys J, 1965, 5(3), 257 doi: 10.1016/S0006-3495(65)86715-7
[4]
Beck S E, Wright H B, Hargy T M, et al. Action spectra for validation of pathogen disinfection in medium-pressure ultraviolet (UV) systems. Water Res, 2015, 70, 27 doi: 10.1016/j.watres.2014.11.028
[5]
Santos A L, Moreirinha C, Lopes D, et al. Effects of UV radiation on the lipids and proteins of bacteria studied by mid-infrared spectroscopy. Environ Sci Technol, 2013, 47(12), 6306 doi: 10.1021/es400660g
[6]
Hijnen W, Beerendonk E, Medema G J. Inactivation credit of UV radiation for viruses, bacteria and protozoan (oo) cysts in water: a review. Water Res, 2006, 40(1), 3 doi: 10.1016/j.watres.2005.10.030
[7]
Sarigiannis D, Karakitsios S, Antonakopoulou M, et al. Exposure analysis of accidental release of mercury from compact fluorescent lamps (CFLs). Sci Total Environ, 2012, 435, 306 doi: 10.1016/j.scitotenv.2012.07.026
[8]
Schalk S, Adam V, Arnold E, et al. UV-lamps for disinfection and advanced oxidation-lamp types, technologies and applications. IUVA News, 2006, 8(1), 32
[9]
da Silveira Petruci J F, Fortes P R, Kokoric V, et al. Real-time monitoring of ozone in air using substrate-integrated hollow waveguide mid-infrared sensors. Sci Reports, 2013, 3(1), 1 doi: 10.1038/srep03174
[10]
Hirayama H, Maeda N, Fujikawa S, et al. Recent progress and future prospects of AlGaN-based high-efficiency deep-ultraviolet light-emitting diodes. Jpn J Appl Phys, 2014, 53(10), 100209 doi: 10.7567/JJAP.53.100209
[11]
Li D, Jiang K, Sun X, et al. AlGaN photonics: recent advances in materials and ultraviolet devices. Adv Opt Photonics, 2018, 10(1), 43 doi: 10.1364/AOP.10.000043
[12]
Kneissl M, Seong T Y, Han J, et al. The emergence and prospects of deep-ultraviolet light-emitting diode technologies. Nat Photonics, 2019, 13(4), 233 doi: 10.1038/s41566-019-0359-9
[13]
Taniyasu Y, Kasu M, Makimoto T. An aluminium nitride light-emitting diode with a wavelength of 210 nanometres. Nature, 2006, 441(7091), 325 doi: 10.1038/nature04760
[14]
Khan A, Balakrishnan K, Katona T. Ultraviolet light-emitting diodes based on group three nitrides. Nat Photonics, 2008, 2(2), 77 doi: 10.1038/nphoton.2007.293
[15]
Nagasawa Y, Hirano A. A review of AlGaN-based deep-ultraviolet light-emitting diodes on sapphire. Appl Sci, 2018, 8(8), 1264 doi: 10.3390/app8081264
[16]
Simon J, Protasenko V, Lian C, et al. Polarization-induced hole doping in wide–band-gap uniaxial semiconductor heterostructures. Science, 2010, 327(5961), 60 doi: 10.1126/science.1183226
[17]
Zhang L, Ding K, Yan J, et al. Three-dimensional hole gas induced by polarization in (0001)-oriented metal-face III-nitride structure. Appl Phys Lett, 2010, 97(6), 062103 doi: 10.1063/1.3478556
[18]
Ryu H Y, Choi I G, Choi H S, et al. Investigation of light extraction efficiency in AlGaN deep-ultraviolet light-emitting diodes. Appl Phys Express, 2013, 6(6), 062101 doi: 10.7567/APEX.6.062101
[19]
Li Y, Wang C, Zhang Y, et al. Analysis of TM/TE mode enhancement and droop reduction by a nanoporous n-AlGaN underlayer in a 290 nm UV-LED. Photonics Res, 2020, 8(6), 806 doi: 10.1364/PRJ.387607
[20]
Bowker C, Sain A, Shatalov M, et al. Microbial UV fluence-response assessment using a novel UV-LED collimated beam system. Water Res, 2011, 45(5), 2011 doi: 10.1016/j.watres.2010.12.005
[21]
Bolton J R, Linden K G. Standardization of methods for fluence (UV dose) determination in bench-scale UV experiments. J Environ Eng, 2003, 129(3), 209 doi: 10.1061/(ASCE)0733-9372(2003)129:3(209)
[22]
Suzuki A, Emoto A, Shirai A, et al. Ultraviolet light-emitting diode (UV-LED) sterilization of citrus bacterial canker disease targeted for effective decontamination of citrus sudachi fruit. Biocontrol Sci, 2022, 27(1), 1 doi: 10.4265/bio.27.1
[23]
Lee Y W, Yoon H D, Park J H, et al. Application of 265-nm UVC LED lighting to sterilization of typical gram negative and positive bacteria. J Korean Physl Soc, 2018, 72(10), 1174 doi: 10.3938/jkps.72.1174
[24]
Huang S Y, Lin J C, Huang X Q, et al. Large-area 280 nm LED flexible sterilization light source with improved thermal performance. Optik, 2021, 248, 168109 doi: 10.1016/j.ijleo.2021.168109
[25]
Kim B S, Youm S, Kim Y K. Sterilization of harmful microorganisms in hydroponic cultivation using an ultraviolet LED light source. Sens Mater, 2020, 32(11), 3773 doi: 10.18494/SAM.2020.2979
[26]
Nunayon S S, Zhang H, Lai A C K. Comparison of disinfection performance of UVC-LED and conventional upper-room UVGI systems. Indoor Air, 2020, 30(1), 180 doi: 10.1111/ina.12619
[27]
Liu S, Luo W, Li D, et al. Sec-eliminating the SARS-CoV-2 by AlGaN based high power deep ultraviolet light source. Adv Funct Mater, 2020, 31, 2008452 doi: 10.1002/adfm.202008452
[28]
Bormann M, Alt M, Schipper L, et al. Disinfection of SARS-CoV-2 contaminated surfaces of personal items with UVC-LED disinfection boxes. Viruses, 2021, 13(4), 598 doi: 10.3390/v13040598
[29]
Tamulaitis G, Mickevičius J, Kazlauskas K, et al. Efficiency droop in high-Al-content AlGaN/AlGaN quantum wells. Phys Status Solidi C, 2011, 8(7/8), 2130 doi: 10.1002/pssc.201000889
[30]
Yun J, Shim J I, Hirayama H. Analysis of efficiency droop in 280-nm AlGaN multiple-quantum-well light-emitting diodes based on carrier rate equation. Appl Phys Express, 2015, 8(2), 022104 doi: 10.7567/APEX.8.022104
[31]
Cho J, Schubert E F, Kim J K. Efficiency droop in light-emitting diodes: Challenges and countermeasures. Laser Photonics Rev, 2013, 7(3), 408 doi: 10.1002/lpor.201200025
[32]
Hu J, Zhang J, Zhang Y, et al. Enhanced performance of AlGaN-based deep ultraviolet light-emitting diodes with chirped superlattice electron deceleration layer. Nanoscale Res Lett, 2019, 14(1), 1 doi: 10.1186/s11671-018-2843-4
[33]
Bolton J R, Cotton C A. The ultraviolet disinfection handbook. Glacier Publishing Services, Inc., 2011
[34]
Rastogi R P, Kumar A, Tyagi M B, et al. Molecular mechanisms of ultraviolet radiation-induced DNA damage and repair. J Nucleic Acids, 2010, 90(6/7), 560 doi: 10.4061/2010/592980
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    Received: 05 May 2022 Revised: Online: Accepted Manuscript: 10 May 2022Uncorrected proof: 12 May 2022Published: 01 July 2022

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      Wei Luo, Tai Li, Yongde Li, Houjin Wang, Ye Yuan, Shangfeng Liu, Weiyun Wang, Qi Wang, Junjie Kang, Xinqiang Wang. Watts-level ultraviolet-C LED integrated light sources for efficient surface and air sterilization[J]. Journal of Semiconductors, 2022, 43(7): 072301. doi: 10.1088/1674-4926/43/7/072301 ****Wei Luo, Tai Li, Yongde Li, Houjin Wang, Ye Yuan, Shangfeng Liu, Weiyun Wang, Qi Wang, Junjie Kang, Xinqiang Wang, Watts-level ultraviolet-C LED integrated light sources for efficient surface and air sterilization[J]. Journal of Semiconductors, 2022, 43(7), 072301 doi: 10.1088/1674-4926/43/7/072301
      Citation:
      Wei Luo, Tai Li, Yongde Li, Houjin Wang, Ye Yuan, Shangfeng Liu, Weiyun Wang, Qi Wang, Junjie Kang, Xinqiang Wang. Watts-level ultraviolet-C LED integrated light sources for efficient surface and air sterilization[J]. Journal of Semiconductors, 2022, 43(7): 072301. doi: 10.1088/1674-4926/43/7/072301 ****
      Wei Luo, Tai Li, Yongde Li, Houjin Wang, Ye Yuan, Shangfeng Liu, Weiyun Wang, Qi Wang, Junjie Kang, Xinqiang Wang, Watts-level ultraviolet-C LED integrated light sources for efficient surface and air sterilization[J]. Journal of Semiconductors, 2022, 43(7), 072301 doi: 10.1088/1674-4926/43/7/072301

      Watts-level ultraviolet-C LED integrated light sources for efficient surface and air sterilization

      DOI: 10.1088/1674-4926/43/7/072301
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      • Wei Luo:got his BS and PhD degrees from School of Physics, Peking University in 2014 and 2019, respectively. Then he joined Institute of Physics, Chinese Academy of Sciences and Songshan Lake Materials Laboratory as postdoc. His research mainly focuses on the growth and physics in III-nitride semiconductors, as well as the fabrication and application of optoelectronic devices
      • Tai Li:got his BE degree in Jilin University in 2019. Currently he is studying for his Ph.D. degree in School of Physics, Peking University. His research interests focus on the MOCVD growth and characterization of III-nitride semiconductors and optoelectronic devices
      • Junjie Kang:received his BS degree from Northwestern Polytechnic University in 2010, PhD degree from the Chinese Academy of Sciences in 2015. After graduation, he worked at Chinese Academy of Engineering Physics from July 2015 to June 2019. During this period, he engaged in postdoctoral researches at Korea University and Singapore University of Technology and Design. His main research fields include semiconductor optoelectronic material growth and device fabrication, micro-nano structure, low-temperature spectra, etc. He participated in a number of national and provincial key research projects
      • Xinqiang Wang:is a full Professor of School of Physics at Peking University. He joined the faculty on May 2008, after more than 6 years’ postdoctoral research at Chiba University and Japan Science Technology Agency, Japan. He has received the China National Funds for Distinguished Young Scientists in 2012 and has been awarded Changjiang Distinguished Professor by Ministry of Education in 2014. He mainly concentrates on III-nitrides compound semiconductors including epitaxy and device fabrication. He is the author or co-author of over 200 refereed journal articles with over 3800 citations and has delivered over 40 invited talks at scientific conferences and contributed three chapters in three books
      • Corresponding author: kangjunjie@sslab.org.cnwangshi@pku.edu.cn
      • Received Date: 2022-05-05
        Available Online: 2022-05-10

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