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硅异质结(SHJ)太阳电池中空穴端接触的电接触性能调控是提升电池效率的关键挑战之一。本文采用TCAD数值模拟，通过构建多子端和少子端接触模型，系统研究了p型硅薄膜(p-layer)接触叠层中的载流子输运行为，重点揭示了诱导p-n结与寄生肖特基结的耦合作用机制及其对接触性能的影响。研究表明，p-layer的激活能(Ea,p)是决定载流子输运行为的核心参数。较低的Ea,p有利于在 p-layer/TCO 界面激发更有效的空穴隧穿方式(B2BT或TAT-DBS)，并在 i-a-Si:H/c-Si界面引入更适合载流子输运的能带弯曲，这不仅显著降低了接触电阻，还抑制了高偏压下的电子电流，从而在宽偏压范围内维持了优异的载流子选择性。同时，在光学方面，低Ea,p有利于拓宽透明导电氧化物(TCO)薄膜的材料选择窗口，选择具有更低载流子浓度的TCO薄膜，从而有效抑制TCO膜层的寄生吸收，提升器件的光谱响应。本研究阐明了空穴传输端的载流子输运机理，明确了关键材料的调控准则，为高性能SHJ太阳电池的界面工程优化和器件设计提供了重要的理论依据与实践指导。The modulation of electrical contact properties at the hole-selective contact represents a critical challenge for enhancing the efficiency of silicon heterojunction (SHJ) solar cells, particularly due to the complex carrier transport in the induced p-n junction at the p-layer/TCO interface. In this work, we systematically investigate the carrier transport behavior within the hole contact stack by employing TCAD numerical simulations. Both the majority- and minority-carrier analyzing models were built, based on the typical TLM (Transfer Length Method) and CSM (Cox and Strack Method) architectures, specifically. Our findings reveal that the activation energy (Ea,p) of p-layer is a decisive parameter governing the carrier transport dynamics. A lower Ea,p (e.g., 100 meV) significantly reduces the hole transport barrier at the p-layer/TCO interface, facilitating dominant band-to-band tunneling (B2BT) or dangling-bond-assisted trap-assisted tunneling (TAT-DBS), while simultaneously optimizing band bending at the i-a-Si:H/c-Si interface to enhance hole collection efficiency. These synergistic effects not only significantly reduce the contact resistivity but also suppress the parasitic electron current under high forward bias, thereby maintaining excellent carrier selectivity over a wide voltage range. From an optical perspective, a lower Ea,p broadens the selection window for transparent conductive oxide (TCO) materials, as it allows the use of TCO films with lower carrier concentration, thereby effectively mitigating parasitic absorption. This study clarifies the carrier transport mechanism at the hole-selective contact and establishes key material design criteria, providing vital theoretical guidance and practical strategies for the interface engineering and performance optimization of next-generation high-efficiency SHJ solar cells, as validated by experimental trends in recent high-efficiency devices.
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Keywords:
- Silicon heterojunction solar cells /
- Numerical simulations /
- Contact resistivity /
- Transport mechanisms
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[1] Lin H, Yang M, Ru X, Wang G, Yin S, Peng F, Hong C, Qu M, Lu J, Fang L, Han C, Procel P, Isabella O, Gao P, Li Z, Xu X 2023 Nat. Energy 8 789
[2] Wang G, Su Q, Tang H, Wu H, Lin H, Han C, Wang T, Xue C, Lu J, Fang L, Li Z, Xu X, Gao P 2024 Nat. Commun 15 8931
[3] Wu H, Ye F, Yang M, Luo F, Tang X, Tang Q, Qiu H, Huang Z, Wang G, Sun Z, Lin H, Wei J, Li Y, Tian X, Zhang J, Xie L, Deng X, Yuan T, Yu M, Liu Y, Li P, Chen H, Zhou S, Xu Q, Li P, Duan J, Chen J, Li C, Yin S, Liu B, Sun C, Su Q, Wang Y, Deng H, Xie T, Gao P, Kang Q, Zhang Y, Yan H, Yuan N, Peng F, Yuan Y, Ru X, He B, Chen L, Wang J, Lu J, Qu M, Xue C, Ding J, Fang L, Li Z, Xu X 2024 Nature 635 604
[4] Wang G, Yu M, Wu H, Li Y, Xie L, Wei J, Deng X, Zhou S, Yuan T, Luo F, Yuan Y, Huang Z, Tang X, Tang Q, Yin S, Qiu H, Liu Y, Yang M, Sun C, Wu L, Lin H, Tang H, Liu Q, Liu H, Chen J, Ru X, Ye F, Qu M, Wang J, Lu J, He B, Chen L, Xue C, Gao P, He D, Fang L, Xu X, Li Z 2025 Nature 647 369
[5] Allen T G, Bullock J, Yang X, Javey A, De Wolf S 2019 Nat. Energy 4 914
[6] Feldmann F, Bivour M, Reichel C, Hermle M, Glunz S W 2014 Sol. Energy Mater. Sol. Cells 120 270
[7] Sun Z, Chen X, He Y, Li J, Wang J, Yan H, Zhang Y 2022 Adv. Energy Mater 12 2200015
[8] Long W, Yin S, Peng F, Yang M, Fang L, Ru X, Qu M, Lin H, Xu X 2021 Sol. Energy Mater. Sol. Cells 231 111291
[9] YUAN H, CHEN X, LIANG B, SUN A, WANG X, ZHAO Y, ZHANG X 2025 Acta Phys. Sin. 74 047801（in Chinese）[袁赫泽, 陈新亮, 梁柄权, 孙爱鑫, 王雪骄, 赵颖, 张晓丹 2025 物理学报 74 047801]
[10] Schulze T F, Korte L, Conrad E, Schmidt M, Rech B 2010 J. Appl. Phys. 107 023711
[11] Muralidharan P, Leilaeioun M A, Weigand W, Holman Z C, Goodnick S M, Vasileska D 2020 IEEE J. Photovoltaics 10 363
[12] Varache R, Kleider J P, Gueunier-Farret M E, Korte L 2013 MAT SCI ENG B-ADV 178 593
[13] Madani Ghahfarokhi O, Von Maydell K, Agert C 2014 Appl. Phys. Lett 104 113901
[14] Bivour M, Schröer S, Hermle M 2013 Energy Procedia 38 658
[15] Ritzau K U, Bivour M, Schröer S, Steinkemper H, Reinecke P, Wagner F, Hermle M 2014 Sol. Energy Mater. Sol. Cells 131 9
[16] Bivour M, Reichel C, Hermle M, Glunz S W 2012 Sol. Energy Mater. Sol. Cells 106 11
[17] Procel P, Xu H, Saez A, Ruiz‐Tobon C, Mazzarella L, Zhao Y, Han C, Yang G, Zeman M, Isabella O 2020 Prog Photovolt Res Appl 28 935
[18] Procel P, Yang G, Isabella O, Zeman M 2018 Sol. Energy Mater. Sol. Cells 186 66
[19] Luderer C, Tutsch L, Messmer C, Hermle M, Bivour M 2021 IEEE J. Photovoltaics 11 329
[20] Lachenal D, Baetzner D, Frammelsberger W, Legradic B, Meixenberger J, Papet P, Strahm B, Wahli G 2016 Energy Procedia 92 932
[21] Cox R H, Strack H 1967 Solid-State Electron 10 1213
[22] Wang W, Lin H, Yang Z, Wang Z, Wang J, Zhang L, Liao M, Zeng Y, Gao P, Yan B, Ye J 2019 IEEE J. Photovoltaics 9 1113
[23] Gao T, Geng Q, Gao Z, Li Y, Chen L, Li M 2021 ACS Appl. Energy Mater. 4 12543
[24] Rached D, Rahal W L 2020 OPTIK 223 165575
[25] Richter A, Werner F, Cuevas A, Schmidt J, Glunz S W 2012 Energy Procedia 27 88
[26] Klaassen D B M 1992 Solid-State Electron 35 953
[27] Shannon J M, Nieuwesteeg K J B M 1993 Appl. Phys. Lett. 62 1815
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