Molecular dynamics (MD) simulations have been employed to study cascade overlap and defect accumulation processes during amorphization in 3C-SiC. A large number of 10 keV displacement cascades were randomly generated in a model crystal to achieve the amorphous state, and the corresponding dose is consistent with experimental observations. The results show that most defects are single interstitials and mono-vacancies at low dose, whereas the amorphous or disordered clusters, which consist of interstitials and antisite defects, appear at intermediate dose levels. These local disordered regions play an important role in the amorphization of SiC. At higher doses, a significant proportion of antisite defects is created during continued cascade overlap. The increase in interstitials and antisite defects with increasing dose suggests that the primary driving force for the crystalline-to-amorphous transition under these ion irradiation conditions in SiC is due to the accumulation of both Frenkel pairs and antisite defects.
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