Eliminating nanometer-scale asperities on metallic thin films through plasma modification processes studied by molecular dynamics and AFM

Abstract We report the effects of reducing surface asperity size at the nanometer scale on metallic surfaces by plasma-assisted surface modification processes using simulations and experiments. Molecular dynamics (MD) simulations were conducted by irradiating various inert gas ions (Ne, Ar, Kr, and...

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Main Authors: Tomoyuki Tsuyama, Tatsuki Oyama, Yu Azuma, Haruhisa Ohashi, Masahiro Irie, Ayumi Yamakawa, Shoko Uetake, Takayuki Konno, Takahiro Ukai, Kohei Ochiai, Nobuyuki Iwaoka, Atsushi Hashimoto, Yoshishige Okuno
Format: Article
Language:English
Published: Nature Portfolio 2025-04-01
Series:Scientific Reports
Online Access:https://doi.org/10.1038/s41598-025-92095-5
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author Tomoyuki Tsuyama
Tatsuki Oyama
Yu Azuma
Haruhisa Ohashi
Masahiro Irie
Ayumi Yamakawa
Shoko Uetake
Takayuki Konno
Takahiro Ukai
Kohei Ochiai
Nobuyuki Iwaoka
Atsushi Hashimoto
Yoshishige Okuno
author_facet Tomoyuki Tsuyama
Tatsuki Oyama
Yu Azuma
Haruhisa Ohashi
Masahiro Irie
Ayumi Yamakawa
Shoko Uetake
Takayuki Konno
Takahiro Ukai
Kohei Ochiai
Nobuyuki Iwaoka
Atsushi Hashimoto
Yoshishige Okuno
author_sort Tomoyuki Tsuyama
collection DOAJ
description Abstract We report the effects of reducing surface asperity size at the nanometer scale on metallic surfaces by plasma-assisted surface modification processes using simulations and experiments. Molecular dynamics (MD) simulations were conducted by irradiating various inert gas ions (Ne, Ar, Kr, and Xe) onto a cobalt slab with nanoscale asperities on the surface. The MD simulations showed that as the atomic number of the inert gas increased the surface asperity size was reduced more efficiently, while the etching rate decreased. The dependencies of the scattering behaviors on the inert gas ions originated from the mass exchange between the working gas ions and the slab atoms. Atomic force microscopy and X-ray fluorescence measurements were performed on hard disk media subjected to the surface modification processes. These measurements experimentally demonstrated that the density of nanoscale asperities was reduced with a lower etching rate as the atomic number of the inert gas increased, consistent with the simulation results. Through this study, we clarified that heavier working gases were more effective in reducing surface asperity size without significantly reducing the thickness of the material, which can contribute to better control of surface morphologies at the nanometer scale.
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publishDate 2025-04-01
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spelling doaj-art-d4d366b4d38f4061a82d9e982a5c8e892025-08-20T02:11:46ZengNature PortfolioScientific Reports2045-23222025-04-011511910.1038/s41598-025-92095-5Eliminating nanometer-scale asperities on metallic thin films through plasma modification processes studied by molecular dynamics and AFMTomoyuki Tsuyama0Tatsuki Oyama1Yu Azuma2Haruhisa Ohashi3Masahiro Irie4Ayumi Yamakawa5Shoko Uetake6Takayuki Konno7Takahiro Ukai8Kohei Ochiai9Nobuyuki Iwaoka10Atsushi Hashimoto11Yoshishige Okuno12Resonac Corporation, Research Center for Computational Science and InformaticsResonac Hard Disk Corporation, Research & Development CenterResonac Hard Disk Corporation, Research & Development CenterResonac Hard Disk Corporation, Research & Development CenterResonac Hard Disk Corporation, Research & Development CenterResonac Hard Disk Corporation, Research & Development CenterResonac Hard Disk Corporation, Research & Development CenterResonac Hard Disk Corporation, Research & Development CenterResonac Hard Disk Corporation, Research & Development CenterResonac Corporation, Research Center for Computational Science and InformaticsResonac Corporation, Research Center for Computational Science and InformaticsResonac Hard Disk Corporation, Research & Development CenterResonac Corporation, Research Center for Computational Science and InformaticsAbstract We report the effects of reducing surface asperity size at the nanometer scale on metallic surfaces by plasma-assisted surface modification processes using simulations and experiments. Molecular dynamics (MD) simulations were conducted by irradiating various inert gas ions (Ne, Ar, Kr, and Xe) onto a cobalt slab with nanoscale asperities on the surface. The MD simulations showed that as the atomic number of the inert gas increased the surface asperity size was reduced more efficiently, while the etching rate decreased. The dependencies of the scattering behaviors on the inert gas ions originated from the mass exchange between the working gas ions and the slab atoms. Atomic force microscopy and X-ray fluorescence measurements were performed on hard disk media subjected to the surface modification processes. These measurements experimentally demonstrated that the density of nanoscale asperities was reduced with a lower etching rate as the atomic number of the inert gas increased, consistent with the simulation results. Through this study, we clarified that heavier working gases were more effective in reducing surface asperity size without significantly reducing the thickness of the material, which can contribute to better control of surface morphologies at the nanometer scale.https://doi.org/10.1038/s41598-025-92095-5
spellingShingle Tomoyuki Tsuyama
Tatsuki Oyama
Yu Azuma
Haruhisa Ohashi
Masahiro Irie
Ayumi Yamakawa
Shoko Uetake
Takayuki Konno
Takahiro Ukai
Kohei Ochiai
Nobuyuki Iwaoka
Atsushi Hashimoto
Yoshishige Okuno
Eliminating nanometer-scale asperities on metallic thin films through plasma modification processes studied by molecular dynamics and AFM
Scientific Reports
title Eliminating nanometer-scale asperities on metallic thin films through plasma modification processes studied by molecular dynamics and AFM
title_full Eliminating nanometer-scale asperities on metallic thin films through plasma modification processes studied by molecular dynamics and AFM
title_fullStr Eliminating nanometer-scale asperities on metallic thin films through plasma modification processes studied by molecular dynamics and AFM
title_full_unstemmed Eliminating nanometer-scale asperities on metallic thin films through plasma modification processes studied by molecular dynamics and AFM
title_short Eliminating nanometer-scale asperities on metallic thin films through plasma modification processes studied by molecular dynamics and AFM
title_sort eliminating nanometer scale asperities on metallic thin films through plasma modification processes studied by molecular dynamics and afm
url https://doi.org/10.1038/s41598-025-92095-5
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