Molecular dynamics simulation of defect production in irradiated β-SiC

We used the molecular dynamics (MD) code MDCASK, in which the Tersoff potential is implemented, to study the mechanisms of defect production due to Si- and C-recoils of different energies in β-SiC. In this paper, we highlight some of our most significant results to date. The threshold displacement energies (TDEs) for Si- and C-atoms have been accurately determined along four main crystallographic directions. The difficulty of defining a single TDE in this material, also because of the effect of temperature, is discussed. High-energy (various keV) recoil-induced displacement cascades have been simulated and it was found that defects on the C-sublattice always outnumber defects on the Si-sublattice, temperature scarcely affecting the number of Frenkel pairs produced within the cascade. Finally, our MD model seems to have proved satisfactory in reproducing the experimentally observed process of irradiation-induced amorphization of SiC at cryogenic temperature.