Review of dynamic recovery effects on ion irradiation damage in ionic-covalent materials

Single crystalline samples of highly ionic Ca2La8(SiO4)6O2 and covalent 6H-SiC have been irradiated with different ions/energies to study the effects of dose, temperature, damage-energy density, and in-cascade ionization rate on the dynamics of irradiation-induced amorphization. Above temperatures of 100-150 K, the dose for complete amorphization, D, increases with temperature in a single stage and exhibits a strong dependence on the ratio of in-cascade recovery to displacement cross sections, σr/σd. A fit of a dynamic model for amorphization to these data indicates that irradiation-induced dynamic recovery occurs with an activation energy of 0.15 ± 0.02 and 0.12 ± 0.01 eV for Ca2La8(SiO4)6O2 and 6H-SiC, respectively. Analysis of these data reveals that ionization processes are the dominant contributor to in-cascade recovery in Ca2La8(SiO4)6O2; while in 6H-SiC, ionization processes are less dominant.