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arXiv · 1510.03680

A quasi-conserved particle Monte Carlo model of surface evolution with semi-empirical sputter yield modulated erosion: 1 keV Ar$^+$ sputtering of Si

Emmanuel Oyewande
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Abstract

We introduce a new Monte Carlo model based on a semi-empirical sputter yield parameter in ion-solid energetic collisions. This model circumvents the complexity of the existing statistical, classical and continuum models, most of which are difficult to relate to real experimental parameters, by its semi-empirical nature of direct reliance on the experimental values of the sputter yield. Constrained by this crucial experimental factor, the model then addresses the multidimensional nature of other accompanying physical processes stochastically; thus reducing the complexity of their computation. This model exhibits the experimentally observed features of solid surfaces that evolve under continuous particle irradiation and allows for a way to study the effect of the different mechanisms of the surface morphology and the nature of their interplay in the dynamics of the surface evolution. Our study of the average surface height reveals that it is constant when eroded particles are redeposited but varies linearly with simulation time, when eroded particles are not redeposited. Our studies also show that the roughening process is not significantly affected by re-deposition of eroded material.

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Emmanuel Oyewande. 2015-10-13. A quasi-conserved particle Monte Carlo model of surface evolution with semi-empirical sputter yield modulated erosion: 1 keV Ar$^+$ sputtering of Si. https://arxiv.org/abs/1510.03680

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