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arXiv · 1203.1167

Solid flow drives surface nanopatterning by ion-beam irradiation

M. Castro·R. Gago·L. Vázquez·J. Muñoz-García·R. Cuerno
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Abstract

Ion Beam Sputtering (IBS) is known to produce surface nanopatterns over macroscopic areas on a wide range of materials. However, in spite of the technological potential of this route to nanostructuring, the physical process by which these surfaces self-organize remains poorly under- stood. We have performed detailed experiments of IBS on Si substrates that validate dynamical and morphological predictions from a hydrodynamic description of the phenomenon. Our results elucidate flow of a nanoscopically thin and highly viscous surface layer, driven by the stress created by the ion-beam, as a description of the system. This type of slow relaxation is akin to flow of macroscopic solids like glaciers or lead pipes, that is driven by defect dynamics.

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M. Castro, R. Gago, L. Vázquez, J. Muñoz-García, R. Cuerno. 2012-03-06. Solid flow drives surface nanopatterning by ion-beam irradiation. https://doi.org/10.1103/physrevb.86.214107

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