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G. Hobler, D. Maciazek, Z. Postawa:
"Crater function moments: Role of implanted noble gas atoms";
Physical Review B, 97 (2018), 155307; 155307-1 - 155307-13.

Spontaneous pattern formation by energetic ion beams is usually explained in terms of surface-curvature
dependent sputtering and atom redistribution in the target. Recently, the effect of ion implantation on surface
stability has been studied for nonvolatile ion species, but for the case of noble gas ion beams it has always been
assumed that the implanted atoms can be neglected. In thiswork, we showby molecular dynamics (MD) andMonte
Carlo (MC) simulations that this assumption is not valid in a wide range of implant conditions. Sequential-impact
MD simulations are performed for 1-keV Ar, 2-keV Kr, and 2-keV Xe bombardments of Si, starting with a pure
single-crystalline Si target and running impacts until sputtering equilibrium has been reached. The simulations
demonstrate the importance of the implanted ions for crater-function estimates. The atomic volumes of Ar, Kr,
and Xe in Si are found to be a factor of two larger than in the solid state. To extend the study to a wider range
of energies, MC simulations are performed. We find that the role of the implanted ions increases with the ion
energy although the increase is attenuated for the heavier ions. The analysis uses the crater function formalism
specialized to the case of sputtering equilibrium.

http://dx.doi.org/10.1103/PhysRevB.97.155307