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 language | English |
|---|---|
| Pages (from-to) | 591-597 |
| Number of pages | 7 |
| Journal | Materials Research Society Symposium - Proceedings |
| Volume | 408 |
| Publication status | Published - 1996 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
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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 journal › Article
}
TY - JOUR
T1 - Computer simulation of cluster ion impacts on a solid surface
AU - Insepov, Z.
AU - Yamada, I.
PY - 1996
Y1 - 1996
N2 - 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.
AB - 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.
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M3 - Article
VL - 408
SP - 591
EP - 597
JO - Materials Research Society Symposium - Proceedings
JF - Materials Research Society Symposium - Proceedings
SN - 0272-9172
ER -