Frenkel pair accumulation in ion- and electron-irradiated SiC

Abstract

Classical MD simulations have been applied to study the Frenkel pair accumulation in electron- and ion-irradiated SiC for a wide temperature range 20–1200K using different dose rates, so that ion flux affects significantly the resulting damage levels. Since the range of experimental dose rates is not accessible in MD simulations because of computational time limitations, an analytical model of amorphization accounting for different fractions of stable Frenkel pairs (FPs) was used to predict FPs generation/recombination behavior at experimental values of ion flux and study their role in crystalline-to-amorphous transition in SiC. Critical temperatures for amorphization using electron and ion irradiation as estimated with the formalism of our model are consistent with experimental data. FPs configurations responsible for damage annealing at different temperatures are discussed. For example, tetrahedral SiTC interstitials are shown to be dominating in the generation-recombination process for the temperature region 200–800K in electron-irradiated SiC.