Abstract
The transition to high-aspect-ratio, eco-friendly plasma etching gases with low global warming potential (GWP) is critical for advancing sustainable semiconductor manufacturing. Hence, the dissociative photoionization dynamics of 1,1,1,2,2,3,4,5,5,5-decafluoropentane (C5H2F10), a promising alternative to conventional high-GWP perfluorocarbons, were comprehensively investigated. Fragmentation mechanisms were elucidated using an integrated approach combining synchrotron-based photoelectron–photoion coincidence (PEPICO) spectroscopy, electron-impact ionization mass spectrometry, and computational quantum chemistry. In addition to mapping the primary fragments (e.g., C4H2F7+, C3H2F5+, and CF3+), this study deciphered the complex rearrangement pathways leading to the prominent and persistent CHF2+ ion, which is a key species that cannot be formed by simple bond cleavage. Computational calculations revealed precise fluorine migration steps and energetic barriers, which were conclusively validated by the strong anticorrelation observed in the time-resolved ion yield curves. Exploration of the influence of electron energy on fragmentation demonstrated that lower energies (20 eV) preserve primary dissociation channels, whereas higher energies (70 eV) drive extensive fragmentation. This study provides a strategic framework for optimizing reactive-species fluxes in next-generation etching processes by linking tunable gas-phase dissociation, including controlled CHF2+ generation, under plasma-relevant conditions.
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The raw data supporting the findings of this study are available from the corresponding author upon reasonable request.
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Acknowledgements
The authors thank the members of the Center for Low-Temperature Plasma Sciences at the Nagoya University. This study was partly supported by JSPS-KAKENHI 21H01073 and JST ASPIRE JPMJAP2321, and was conducted at the BL3B of the UVSOR Synchrotron Facility, Institute for Molecular Science (IMS program 23IMS6015). The authors are grateful to KANTO DENKA KOGYO Co., LTD. for their collaboration in this work.
Funding
This study was partly supported by JSPS-KAKENHI 21H01073 and JST ASPIRE JPMJAP2321.
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Tran Trung Nguyen: Writing—review & editing, Writing—original draft, Investigation, Data curation. Toshio Hayashi: Investigation, Data curation. Hiroshi Iwayama: Investigation, Data curation & resources.Kenji Ishikawa: Supervision, Writing—review & editing, Validation, Conceptualization.
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Tran, N.T., Hayashi, T., Iwayama, H. et al. Photodissociation and electron-collision induced dissociation of C5H2F10 using photoelectron–photoion coincidence spectroscopy and quantum chemistry. Sci Rep (2026). https://doi.org/10.1038/s41598-026-36140-x
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DOI: https://doi.org/10.1038/s41598-026-36140-x
