High-temperature threshold of damage of SiC by swift heavy ions

TL;DR

This study investigates how high temperatures up to 2200 K affect the damage threshold of SiC when irradiated with swift heavy ions, revealing temperature-dependent damage mechanisms and formation of nanometric voids.

Contribution

It provides the first experimental and computational analysis of SiC's irradiation stability at elevated temperatures, identifying a damage threshold around 1800 K.

Findings

Damage threshold of ~1800 K identified for SiC under SHI irradiation.

Higher temperatures lead to larger voids and more stable damage structures.

Recrystallization occurs within 100 ps at lower temperatures.

Abstract

At ambient conditions, SiC is known to be resistant to irradiation with swift heavy ions (SHI) decelerating in the electronic stopping regime. However, there is no experimental data on the SiC irradiation at elevated temperatures. To investigate this problem, we evaluate the stability of SiC to SHI impacts at high temperatures up to 2200 K. We apply the combination of the Monte-Carlo code TREKIS-3, describing excitation of the electronic and atomic systems using temperature-dependent scattering cross-sections, with molecular-dynamic modeling of the lattice response to the excitation. We demonstrate that increasing irradiation temperature increases the energy transferred to the atomic lattice from the excited electronic system. This material heating leads to formation of a stable nanometric damaged core along the trajectory of 710 MeV Bi ion when the irradiation temperature overcomes the threshold of ~1800 K. In this case, a chain of nanometric voids along the ion trajectory forms due to the mass transport from the track core by edge dislocations. Voids of larger sizes appear at higher irradiation temperatures. At lower irradiation temperatures, the damaged regions recrystallize completely within ~100 ps after the ion passage.