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Industrial-scale deposition of nanocrystalline silicon oxide for 26.4%-efficient silicon heterojunction solar cells with copper electrodes

Nature Energy volume 8, pages 1375–1385 (2023)Cite this article

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Abstract

To unlock the full performance potential of silicon heterojunction solar cells requires reductions of parasitic absorption and shadowing losses. Yet the translation of the hydrogenated nanocrystalline silicon oxide (nc-SiOx:H) window layer and copper-plated electrodes to a cost-effective and scalable production-relevant context remains one of the largest roadblocks towards mainstream adoption of silicon heterojunction technology. Here we address the first challenge by developing an industrial-scale high-frequency plasma-enhanced chemical vapour deposition system with a minimized standing wave effect, enabling the deposition of doped nc-SiOx:H with excellent electron selectivity, low parasitic absorption and high uniformity. Next, we demonstrate seed-free copper plating, resulting in grids with a high aspect ratio and low metal fraction. By implementing the doped nc-SiOx:H window layer, certified efficiencies of 25.98% and 26.41% are obtained for M6-size bifacial silicon heterojunction devices with screen-printed silver electrodes and copper-plated electrodes, respectively. These results underline the performance potential of silicon heterojunction technology and lower the threshold towards their mass manufacturing.

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Fig. 1: SHJ solar cell structure and performance.
Fig. 2: Dependence of SHJ device parameters on the thickness of nc-SiOx:H(n) layer deposited under VHF1.
Fig. 3: Thickness-dependent microstructure and contact resistivity of nc-SiOx:H(n) layers deposited under VHF1.
Fig. 4: Dependence of nc-SiOx:H(n) uniformity and device performance on frequency.
Fig. 5: Simulative voltage distribution on frequency.
Fig. 6: Dark degradation of SHJ solar cells and mechanism.
Fig. 7: SHJ solar cell with Cu-plated electrode.

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Acknowledgements

X.Y. acknowledges the financial support from the National Natural Science Foundation of China (no. 62174114), the National Key R&D Program of China (no. 2022YFB4200203), the Department of Science and Technology of Jiangsu Province (no. BE2022027, no. BE2022036, no. BE2022023), the Distinguished Professor Award of Jiangsu Province and the ‘Dual Carbon’ Science and Technology Project of Suzhou (no. ST202219). X.Z. acknowledges the financial support from the Major Research Plan of the National Natural Science Foundation of China (no. 91833303) and the Foundation for Innovation Research Groups of the National Natural Science Foundation of China (no. 51821002). J. Zhou acknowledges the financial support from the Carbon Emission Peak and Carbon Neutrality Special Fund of Jiangsu Province (no. BA2022205). This work is partly supported by the Australian Renewable Energy Agency (ARENA) under 2020/ARP006. The views expressed herein are not necessarily the views of the Australian Government, and the Australian Government does not accept responsibility for any information or advice contained herein. We thank X. Ran, J. Allen and S. Drury for sample preparation and device fabrication.

Author information

Author notes

  1. These authors contributed equally: Cao Yu, Kun Gao.

Authors and Affiliations

  1. Suzhou Maxwell Technologies Co., Ltd., Suzhou, China

    Cao Yu, Chen-Wei Peng, Chenran He, Jiteng Zhang, Dengzhi Wang, Gangyu Tian, Gangqiang Dong, Hao Jiang, Haihong Wu, Xinmin Cao & Jian Zhou

  2. College of Energy, Soochow Institute for Energy and Materials InnovationS (SIEMIS), Soochow University, Suzhou, China

    Cao Yu, Kun Gao, Shibo Wang, Wei Shi, Qing Ma, Xinyu Wang, Dacheng Xu, Kun Li & Xinbo Yang

  3. SunDrive Solar Pty., Ltd., Kirrawee, New South Wales, Australia

    Vince Allen, Youzhong Hu, Jack Colwell, Huiting Wu, Liangyuan Guo, Daniel Chen & Alison Lennon

  4. Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Ministry of Education), School of Physics, Dalian University of Technology, Dalian, China

    Yifan Zhang & Yuanhong Song

  5. College of Artificial Intelligence, Southwest University, Chongqing, China

    Wenzhu Jia

  6. Institute of Functional Nano & Soft Materials (FUNSOM), Soochow University, Suzhou, China

    Chunfang Xing, Jun Peng & Xiaohong Zhang

  7. Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Soochow University, Suzhou, China

    Jun Peng, Xinbo Yang & Xiaohong Zhang

  8. Research Center for New Energy Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, China

    Wenzhu Liu

  9. School of Photovoltaic and Renewable Energy Engineering, The University of New South Wales (UNSW), Sydney, New South Wales, Australia

    Daniel Chen & Alison Lennon

  10. KAUST Solar Center, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia

    Stefaan De Wolf

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  1. Cao Yu
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Contributions

X.Y. and C.Y. conceived the idea, designed the experiments and led the project. C.Y. and K.G. fabricated the devices, performed the device characterizations and wrote the paper. C.-W.P. and C.H. helped with the device optimization and analysis. S.W. and W.S. performed the Raman spectra and contact resistivity measurements. J. Zhang and D.W. performed the large-scale uniformity experiment. V.A., Y.H., J.C., Huiting Wu, L.G., D.C. and A.L. designed and carried out the copper plating. G.T., Y.Z., W.J. and Y.S. performed the simulation validation of the voltage distribution on excitation frequency and substrate size. G.D. performed the TCO deposition, and H.J. performed screen printing. Haihong Wu performed lifetime, EQE and HR-TEM measurements. C.X., Q.M. and X.W. performed HR-TEM and EQE measurements. K.L. and D.X. performed the absorption spectra and optical bandgap measurement. J.P. and W.L. helped with the TOF-SIMS result analysis and discussion. X.C. designed the PECVD chamber. S.D.W. helped with the discussion of the results. J. Zhou, X.Y. and X.Z. supervised the project. All authors contributed to the discussion of the results and revision of the manuscript.

Corresponding authors

Correspondence to Alison Lennon, Jian Zhou, Xinbo Yang or Xiaohong Zhang.

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Competing interests

C.Y., C.-W.P., C.H., J. Zhou, D.W., G.T., G.D., H.J., Haihong Wu, X.C. and J. Zhang are employees of Suzhou Maxwell Technologies Co. Ltd. V.A., D.C., A.L., Y.H., J.C., Huiting Wu and L.G. are employees of SunDrive Solar Pty., Ltd. All other authors declare no competing interests.

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Supplementary information

Supplementary Information

Supplementary Tables 1 and 2, Figs. 1–12, note and references.

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Supplementary Data 1

Source data for Supplementary Fig. 2.

Supplementary Data 2

Source data for Supplementary Fig. 3.

Supplementary Data 3

Source data for Supplementary Fig. 4.

Supplementary Data 4

Source data for Supplementary Fig. 7.

Supplementary Data 5

Source data for Supplementary Figs. 8 and 11.

Source data

Source Data Fig. 1

Certified I–V and EQE data.

Source Data Fig. 2

Photovoltaic parameter data.

Source Data Fig. 3

Raman and contact resistivity data.

Source Data Fig. 4

Thickness and PCE uniformity data.

Source Data Fig. 5

Voltage distribution simulation data.

Source Data Fig. 6

PCE and TOF-SIMS data.

Source Data Fig. 7

Certified I–V data.

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Yu, C., Gao, K., Peng, CW. et al. Industrial-scale deposition of nanocrystalline silicon oxide for 26.4%-efficient silicon heterojunction solar cells with copper electrodes. Nat Energy 8, 1375–1385 (2023). https://doi.org/10.1038/s41560-023-01388-4

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