Modeling of Temperature Effects on the Formation of Tracks of Swift Heavy Ions in Silicon Carbide

Abstract

A hybrid multiscale model consisting of two coupled modules is used to study the effect of irradiation temperature on the kinetics of the formation of swift heavy ions tracks in silicon carbide (6H-SiC). Excitation of the electronic and atomic subsystems of the material is simulated using the Monte Carlo TREKIS-3 code. The profile of energy transferred to the atomic lattice is used as the initial conditions for molecular-dynamics simulations (using the LAMMPS package) of structural changes in the material near the trajectory of the swift heavy ion. Using the example of Bi-ion irradiation with an energy of 710 MeV, it is found that increasing irradiation temperature leads to an increase in the energy density transferred to the lattice. This induces rapid disordering of the core structure of the track at timescales on the order of 0.25 ps. At irradiation temperatures below 1800 K, subsequent recrystallization of the amorphous region within the cooling track leads to complete restoration of the material structure. At temperatures above the threshold of 1800 K, mass transfer, determined by the ejection of dislocations from the track core, results in the formation of nanoscale voids with a diameter of approximately 3 nm along the ion trajectory. The simulation results are useful for assessing the radiation resistance of silicon carbide under extreme irradiation conditions and for formulating ideas and designing new experiments on high-temperature SiC irradiation.