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Structural and optical studies of molybdenum oxides thin films obtained by thermal evaporation and atomic layer deposition methods for photovoltaic application

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Abstract

MoOX (X < 3) has shown its promising potential as an efficient hole-selective passivating contact in crystalline Si solar cells. The device performance highly depends on the film properties of MoOX film, which is significantly affected by different synthesis methods. In this work, Si solar cells with c-Si(p)/MoOX rear contacts were demonstrated, where the MoOX films were realized by thermal evaporation (TE), atomic layer deposition (ALD), and UV-assisted ALD (UV-ALD) methods. A pronounced efficiency drop was disclosed with the order of TE, ALD, and UV-ALD MoOX. Subsequently, the contact propertieis, crystallinity, chemical states, roughness, density, and refractive indices of MoOX films were systematically characterized by a series of microscopic and spectroscopic analyses. It is found that the TE film is composed of nanocrystals, while ALD methods yield amorphous feature with a smaller density and refractive indices. A mild UV illumination (3.5 mW/cm2) slightly reduces the film roughness, while a stronger (35 mW/cm2) one increases the film density, roughness, and growth rate significantly.

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The authors declare that materials described in the paper, including all relevant raw data, will be freely available to any scientist wishing to use them for non-commercial purposes, without breaching participant confidentiality.

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Acknowledgements

This work was financially supported by the National Natural Science Foundation of China (61622407), Science & Technology Commission of Shanghai Municipality (19ZR1479100), the Shanxi Science and Technology Department (20201101012), and the Youth Innovation Promotion Association of the Chinese Academy of Sciences (No. 2019287).

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Author notes

  1. Tianyu Pan and **gye Li contributed equally to this work.

Authors and Affiliations

  1. CAS Key Lab of Low-Carbon Conversion Science and Engineering, Shanghai Advanced Research Institute, Chinese Academy of Sciences, 99 Haike Road, Zhangjiang Hi-Tech Park, Pudong, Shanghai, 201210, China

    Tianyu Pan, **gye Li, Yinyue Lin, Min Yin, Linfeng Lu & Dongdong Li

  2. State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, 865 Changning Road, Shanghai, 200050, China

    Zhongying Xue & Zengfeng Di

  3. **neng Clean Energy Technology Ltd, 533 Guang’an Street, **zhong, 030600, China

    Jilei Wang & Liyou Yang

  4. School of Microelectronics, University of Chinese Academy of Sciences, 19 Yuquan Road, Bei**g, 100049, China

    Tianyu Pan & Dongdong Li

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  1. Tianyu Pan
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Contributions

Conceptualization: TP and DL. Data curation: TP. Formal Analysis: TP and DL. Funding acquisition: DL. Investigation: TP. Methodology: TP. Project administration: DL. Resources: ZX, ZD, and DL. Software: TP. Supervision: DL. Validation: YL. Visualization: JL and YL. Writing—original draft: TP and JL. Writing—review & editing: DL.

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Correspondence to Dongdong Li.

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Pan, T., Li, J., Lin, Y. et al. Structural and optical studies of molybdenum oxides thin films obtained by thermal evaporation and atomic layer deposition methods for photovoltaic application. J Mater Sci: Mater Electron 32, 3475–3486 (2021). https://doi.org/10.1007/s10854-020-05094-9

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