References
  1. Y. Chen, H. Shen, P. P. Altermatt. Analysis of recombination losses in screen-printed aluminum-alloyed back surface fields of silicon solar cells by numerical device simulation. Solar Energy Materials and Solar Cells. 2014;120, 356-362. doi:https://doi.org/10.1016/j.solmat.2013.05.051
  2. A. W. Blakers, A. Wang, A. M. Milne, J. Zhao, M. A. Green. 22.8% efficient silicon solar cell. Applied Physics Letters.1989;55(13), 1363-1365. doi:10.1063/1.101596
  3. P. J. Verlinden. Future challenges for photovoltaic manufacturing at the terawatt level. Journal of Renewable and Sustainable Energy. 2020;12(5), 1-6. doi: 10.1063/5.0020380
  4. L. Cai, W. Wang, L. Jin, Z. Yao, W. Lin, et al. 12.29% low temperature-processed dopant-free cds/p-si heterojunction solar cells.Advanced Materials Interfaces. 2019;6(12),. doi:10.1002/admi.201900367
  5. A. Richter, J. Benick, F. Feldmann, A. Fell, M. Hermle, et al. N-type si solar cells with passivating electron contact: Identifying sources for efficiency limitations by wafer thickness and resistivity variation. Solar Energy Materials and Solar Cells. 2017;173, 96-105. doi:10.1016/j.solmat.2017.05.042
  6. T. C. Kho, K. Fong, K. McIntosh, E. Franklin, N. Grant, et al. Exceptional silicon surface passivation by an ono-dielectric stack.Solar Energy Materials and Solar Cells. 2019. 189,145-253. doi:10.1016/j.solmat.2018.05.061
  7. J. Bullock, M. Hettick, J. Geissbuhler, A. J. Ong, T. Allen, et al. Efficient silicon solar cells with dopant-free asymmetric heterocontacts. Nature Energy. 2016;1. doi:10.1038/Nenergy.2015.31
  8. J. Dréon, Q. Jeangros, J. Cattin, J. Haschke, L. Antognini, et al. 23.5%-efficient silicon heterojunction silicon solar cell using molybdenum oxide as hole-selective contact. Nano Energy.2020;70. doi:10.1016/j.nanoen.2020.104495
  9. W. Wu, W. Lin, J. Bao, Z. Liu, B. Liu, et al. Dopant-free multilayer back contact silicon solar cells employing V2Ox/metal/ V2Ox as an emitter. RSC Advances. 2017;7(38), 23851-23858. doi:10.1039/c7ra03368k
  10. W. Lin, W. Wu, J. Bao, Z. Liu, K. Qiu, et al. Novel hole selective CrOx contact for dopant-free back contact silicon solar cells. Materials Research Bulletin. 2018;103, 77-82. doi:10.1016/j.materresbull.2018.03.032
  11. X. Yang, E. Aydin, H. Xu, J. Kang, M. Hedhili, et al. Tantalum nitride electron-selective contact for crystalline silicon solar cells.Advanced Energy Materials. 2018;8(20). doi:10.1002/aenm.201800608
  12. S. Jackle, M. Liebhaber, C. Gerstmann, M. Mews, K. Jager, et al. Potential of PEDOT:PSS as a hole selective front contact for silicon heterojunction solar cells. Scientific Reports. 2017;7(1), 2170. doi:10.1038/s41598-017-01946-3
  13. L. Cao, P. Procel, A. Alcañiz, J. Yan, F. Tichelaar, et al. Achieving 23.83% conversion efficiency in silicon heterojunction solar cell with ultra-thin MoOx hole collector layer via tailoring (i)a‐si:H/MoOx interface.Progress in Photovoltaics: Research and Applications. 2022. doi:10.1002/pip.3638
  14. J. Bullock, P. T. Zheng, Q. Jeangros, M. Tosun, M. Hettick, et al. Lithium fluoride based electron contacts for high efficiency n-type crystalline silicon solar cells. Advanced Energy Materials.2016;6(14). doi:10.1002/aenm.201600241
  15. W. Wang, J. He, D. Yan, C. Samundsett, S. P. Phang, et al. 21.3%-efficient n-type silicon solar cell with a full area rear TiOx /lif/al electron-selective contact.Solar Energy Materials and Solar Cells. 2020;206. doi:10.1016/j.solmat.2019.110291
  16. W. Wang, J. He, L. Cai, Z. Wang, S. K. Karuturi, et al. Solution‐processed electron‐selective contacts enabling 21.8% efficiency crystalline silicon solar cells. Solar RRL. 2020;4(12). doi:10.1002/solr.202000569
  17. Y. Zhang, W. Cui, Y. Zhu, F. Zu, L. Liao, et al. High efficiency hybrid PEDOT:PSS/nanostructured silicon Schottky junction solar cells by doping-free rear contact. Energy & Environmental Science. 2015;8(1), 297-302. doi:10.1039/c4ee02282c
  18. X. Yang, Q. Bi, H. Ali, K. Davis, W. V. Schoenfeld, et al. High-performance tio2 -based electron-selective contacts for crystalline silicon solar cells. Advanced Materials. 2016;28(28), 5891-5897. doi:10.1002/adma.201600926
  19. Y. Wan, C. Samundsett, J. Bullock, T. Allen, M. Hettick, et al. Magnesium fluoride electron-selective contacts for crystalline silicon solar cells. ACS Applied Material Interfaces. 2016;8(23), 14671-14677. doi:10.1021/acsami.6b03599
  20. L. Zhang, L. Meng, L. Cai, Z. Chen, W. Lin, et al. High‐performance europium fluoride electron‐selective contacts for efficient crystalline silicon solar cells. Solar RRL. 2021;5(8). doi:10.1002/solr.202100057
  21. N. Chen, L. Cai, F. Xie, W. Wang, H. Wei, et al. Gadolinium fluoride as a high-thickness-tolerant electron-selective contact material for solar cells. ACS Applied Energy Materials. 2022;5(4), 4351-4357. doi:10.1021/acsaem.1c03919
  22. W. Wang, L. Cai, L. Meng, L. Zhang, N. Chen, et al. Cerous fluoride dopant‐free electron‐selective contact for crystalline silicon solar cells. Physica status solidi (RRL) -Rapid Research Letters.2021;15(9). doi:10.1002/pssr.202100135
  23. X. Yang, P. Zheng, Q. Bi, K. Weber. Silicon heterojunction solar cells with electron selective TiOx contact.Solar Energy Materials and Solar Cells. 2016;150, 32-38. doi:10.1016/j.solmat.2016.01.020
  24. W. B. Ji, T. Allen, X. B. Yang, G. S. Zeng, S. De Wolf, et al. Polymeric electron-selective contact for crystalline silicon solar cells with an efficiency exceeding 19%. ACS Energy Letters.2020;5(3), 897-902. doi:10.1021/acsenergylett.0c00110
  25. L. Zeng, L. Cai, Z. Wang, N. Chen, Z. Liu, et al. A high-quality dopant-free electron-selective passivating contact made from ultra-low concentration water solution. Nanomaterials (Basel).2022;12(23). doi:10.3390/nano12234318
  26. Z. Yao, L. Cai, L. Meng, K. Qiu, W. Lin, et al. High-performance and stable dopant-free silicon solar cells with magnesium acetylacetonate electron-selective contacts. Physica Status Solidi-Rapid Research Letters. 2020;14(6). doi:10.1002/pssr.202000103
  27. J Bullock, Y. Wan, Z Xu, D Yan, P Phang, et al. 23% n-type crystalline silicon solar cells with TiOx / LiFx /Al partial rear contacts. 2018. doi:10.1109/PVSC.2018.8547414
  28. Lippert, F. An introduction to toothpaste - its purpose, history and ingredients. Monographs in Oral Science. 2013;23. doi:10.1159/000350456
  29. F. Lin, X. Liu, Y. Li, Y. Hu, X. Guo. Ultrathin metal fluoride interfacial layers for use in organic photovoltaic cells.Advanced Functional Materials. 2015;25(44), 6906-6912. doi:10.1002/adfm.201502871
  30. S. Huang, Y. Pang, X. Li, Y. Wang, A. Yu, et al. Strontium fluoride and zinc oxide stacked structure as an interlayer in high-performance inverted polymer solar cells. ACS Applied Material Interfaces 2019;11(2), 2149-2158. doi:10.1021/acsami.8b18963
  31. R. P. Vasquez. SrF2 by XPS. Surface Science Spectra. 1992;1(1), 24-30. doi:10.1116/1.1247687
  32. J. Cho, J. Melskens, M. Debucquoy, M. Recamán Payo, S. Jambaldinni, et al. Passivating electron-selective contacts for silicon solar cells based on an a-si:H/TiOx stack and a low work function metal. Progress in Photovoltaics: Research and Applications. 2018;26(10), 835-845. doi:10.1002/pip.3023
  33. V. Kanchana, G. Vaitheeswaran, M. Rajagopalan. Structural phase stability of caf2 and srf2 under pressure. Physica B: Condensed Matter. 2003;328(3-4), 283-290. doi:10.1016/s0921-4526(02)01851-3
  34. Y. Seino, S. Yoshikawa, M. Abe, S. Morita. Growth dynamics of insulating SrF2 films on si(111). Journal of Physics: Condensed Matter. 2007;19(44), 445001. doi:10.1088/0953-8984/19/44/445001
  35. R. H. Cox, H. Strack. Ohmic contacts for GaAs devices. Solid-State Electronics. 1967;10(12), 1213. doi:10.1016/0038-1101(67)90063-9
  36. Z. Chen, W. Lin, Z. Liu, L. Cai, Y. Chen, et al. Yttrium fluoride-based electron-selective contacts for crystalline silicon solar cells. ACS Applied Energy Materials. 2021;4(3), 2158-2164. doi:10.1021/acsaem.0c02646
  37. Y. Wan, C. Samundsett, J. Bullock, M. Hettick, T. Allen, et al. Conductive and stable magnesium oxide electron-selective contacts for efficient silicon solar cells. Advanced Energy Materials.2017;7(5). doi:10.1002/aenm.201601863
  38. P. Shen, C. Su, Y. Lin, A. Chou, C. Cheng, et al. Ultralow contact resistance between semimetal and monolayer semiconductors.Nature. 2021;593(7858), 211-217. doi:10.1038/s41586-021-03472-9
  39. L. G. Gerling, C. Voz, R. Alcubilla, J. Puigdollers. Origin of passivation in hole-selective transition metal oxides for crystalline silicon heterojunction solar cells. Journal of Materials Research. 2017;32(2), 260-268. doi:10.1557/jmr.2016.453
  40. N. Chen, L. Cai, F. Xie, W. Wang, H. Wei, et al. Gadolinium fluoride as a high-thickness-tolerant electron-selective contact material for solar cells. ACS Applied Energy Materials. 2022;5(4), 4351-4357. doi:10.1021/acsaem.1c03919
  41. Liu, Y.; Huang, Y.; Duan, X. Van der Waals integration before and beyond two-dimensional materials. Nature 2019;567, 323−333. doi:10.1038/s41586-019-1013-x
  42. L. Zhang, L. Meng, L. Cai, Z. Chen, W. Lin, et al. High‐performance europium fluoride electron-selective contacts for efficient crystalline silicon solar cells. Solar RRL. 2021;5(8). doi:10.1002/solr.202100057