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Propagation of Ripples in Monte Carlo Models of Sputter Induced Surface Morphology

Emmanuel O. Yewande·Alexander K. Hartmann·Reiner Kree
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Abstract

Periodic ripples generated from the off-normal incidence ion beam bombardment of solid surfaces have been observed to propagate with a dispersion in the velocity. We investigate this ripple behaviour by means of a Monte Carlo model of the erosion process, in conjuction with one of two different surface diffusion mechanisms, representative of two different classes of materials; one is an Arrhenius-type Monte Carlo method including a term (possibly zero) that accounts for the Schwoebel effect, the other a thermodynamic mechanism without the Schwoebel effect. We find that the behavior of the ripple velocity and wavelength depends on the sputtering timescale, qualitatively consistent with experiments. Futhermore, we observe a strong temperature dependance of the ripple velocity, calling for experiments at different temperatures. Also, we observe that the ripple velocity vanishes ahead of the periodic ripple pattern.

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Emmanuel O. Yewande, Alexander K. Hartmann, Reiner Kree. 2005-02-18. Propagation of Ripples in Monte Carlo Models of Sputter Induced Surface Morphology. https://doi.org/10.1103/physrevb.71.195405

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