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Si nanocluster formation during rapid cooling from high temperature Si vapors and its subsequent interaction with substrate was simulated by molecular dynamics. It was confirmed that several nm sized clusters with a loosely bound structure form during rapid cooling and their metastable structures are retained even at temperatures below the Si melting point. Such globular clusters tend to rearrange themselves upon impingement to be a similar structure to that of the substrate, at least near the cluster/substrate interface. This is suggestive of the role of clusters formed under the mesoplasma condition as growth precursors for fast rate epitaxy. [ABSTRACT FROM AUTHOR]

The formation dynamics of nano-sized hydrogenated Si (Si : H) clusters and their interaction with the Si(1 0 0) substrate have been investigated with molecular dynamics simulation using the Tersoff potential. Several nm-sized clusters comprising H atoms are obtained during rapid cooling of atomic Si and H vapour mixtures. Upon surface impingement, the Si : H clusters display higher degrees of deformation and atomic self-ordering than the Si clusters formed with no H atom incorporation. This is due to the movement of the high potential H atoms toward the cluster surface during deformation, not to the local heat generation by the atomic H recombination within the cluster. [ABSTRACT FROM AUTHOR]

Abstract: The dynamics of Si nano-clusters during epitaxial growth has been investigated with molecular dynamics simulation using the Tersoff potential. Several nm sized Si cluster formed during rapid cooling was found to deform instantaneously upon impingement on a Si(100) substrate at the same time with the spontaneous ordering of the atomic structure to that of the substrate. Due to the increased fraction of high-energy atoms at the surface, smaller clusters (∼1nm) are favorable for such a deformation even at lower temperatures. This is the advantage of loosely-bound cluster as growth precursor to attain epitaxy with reduced impact energies. [Copyright &y& Elsevier]