Crystal Growth And Nucleation in Liquid Silicon During Natural Cooling: A molecular-dynamics simulation

摘要

Molecular dynamics simulations have been performed under three different temperature conditions to investigate the velocity and kinetic energy distributions of atoms during natural cooling, and the crystal growth and nucleation processes of liquid Si have been investigated. The interatomic forces acting on the particles were calculated using the Tersoff potential. The newly developed natural cooling system simulated by determining the atomic movements with a combination of Langevin and Newton equations was employed for cooling the overall system. The influence of the effect of temperature conditions on the crystal growth and nucleation processes was also investigated. We found that the velocity of crystal growth and nucleation of Si could be separated into the general epitixial growth, and crystal growth and concomitant nucleation processes according to the process temperatures. It was found that the nucleus was nucleated in the temperature range of 1,850 K - 1,950 K under the temperature gradient of about 11.1A.