Computer simulation of cluster ion impacts on a solid surface

Z. Insepov, I. Yamada

Research output: Contribution to journalArticle

Abstract

The sputtering probabilities for normal and oblique cluster ion impacts were calculated by the use of two-dimensional molecular dynamics (MD) calculations. These simulations have revealed the angular dependence of ejecting surface atoms on the cluster incidence angle. The ejecting flux has a symmetrical form with an essential lateral component in the case of normal cluster incidence. For an oblique cluster indidence we found a sharp asymmetry of sputtering orientation. We obtained that the ejecting flux consists of three components: a) fast flying atoms with the velocities higher than the cluster velocity ν approx. 2.3ν0, b) approximately self-similar component with ν ≈ ν0, and, finally, c) slowly moving tail with ν approx. 0.2ν0, where ν0 is the cluster velocity. According to our MD results we developed a new model of surface modification phenomena which consists of the Langevin Dynamics based on the Kardar-Parisi-Zhang equation, combined with a Monte-Carlo procedure for crater formation at normal and oblique cluster impacts. We obtained that for a symmetrical crater shape with a size in the order of 20 angstrom, a significant smoothing occurs after irradiation by approx. 103 cluster impacts which has been supported by experiment at dose of approx. 1014 ion/cm2. The rate of the smoothing process can be significantly accelerated if the lateral sputtering phenomenon is taken into account. Simulation of oblique cluster impact on a surface at a grazing angle of 30° by constructing of asymmetric crater shape gives an opposite result: the surface roughness increases. The latter obtaining qualitatively agrees with the experiment.

Original languageEnglish
Pages (from-to)591-597
Number of pages7
JournalMaterials Research Society Symposium - Proceedings
Volume408
Publication statusPublished - 1996
Externally publishedYes

Fingerprint

ion impact
solid surfaces
Sputtering
computerized simulation
Ions
Molecular dynamics
Computer simulation
Fluxes
Atoms
craters
Surface treatment
sputtering
Surface roughness
Experiments
Irradiation
smoothing
incidence
molecular dynamics
grazing
atoms

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials

Cite this

Computer simulation of cluster ion impacts on a solid surface. / Insepov, Z.; Yamada, I.

In: Materials Research Society Symposium - Proceedings, Vol. 408, 1996, p. 591-597.

Research output: Contribution to journalArticle

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