+ abstract = "Atomistic simulations on the silicon carbide
+ precipitation in bulk silicon employing both, classical
+ potential and first-principles methods are presented.
+ The calculations aim at a comprehensive, microscopic
+ understanding of the precipitation mechanism in the
+ context of controversial discussions in the literature.
+ For the quantum-mechanical treatment, basic processes
+ assumed in the precipitation process are calculated in
+ feasible systems of small size. The migration mechanism
+ of a carbon \hkl<1 0 0> interstitial and silicon \hkl<1
+ 1 0> self-interstitial in otherwise defect-free silicon
+ are investigated using density functional theory
+ calculations. The influence of a nearby vacancy,
+ another carbon interstitial and a substitutional defect
+ as well as a silicon self-interstitial has been
+ investigated systematically. Interactions of various
+ combinations of defects have been characterized
+ including a couple of selected migration pathways
+ within these configurations. Almost all of the
+ investigated pairs of defects tend to agglomerate
+ allowing for a reduction in strain. The formation of
+ structures involving strong carbon-carbon bonds turns
+ out to be very unlikely. In contrast, substitutional
+ carbon occurs in all probability. A long range capture
+ radius has been observed for pairs of interstitial
+ carbon as well as interstitial carbon and vacancies. A
+ rather small capture radius is predicted for
+ substitutional carbon and silicon self-interstitials.
+ Initial assumptions regarding the precipitation
+ mechanism of silicon carbide in bulk silicon are
+ established and conformability to experimental findings
+ is discussed. Furthermore, results of the accurate
+ first-principles calculations on defects and carbon
+ diffusion in silicon are compared to results of
+ classical potential simulations revealing significant
+ limitations of the latter method. An approach to work
+ around this problem is proposed. Finally, results of
+ the classical potential molecular dynamics simulations
+ of large systems are examined, which reinforce previous
+ assumptions and give further insight into basic
+ processes involved in the silicon carbide transition.",