Modeling of long-term defect evolution in heavy-ion irradiated 3C-SiC: Mechanism for thermal annealing and influences of spatial correlation

TL;DR

This study develops a multi-scale simulation framework combining MD and KMC to investigate long-term defect evolution in heavy-ion irradiated 3C-SiC, revealing key annealing behaviors and the limited impact of spatial correlation at high damage doses.

Contribution

It introduces a multi-scale modeling approach integrating MD and KMC to analyze defect evolution and annealing mechanisms in irradiated 3C-SiC, highlighting the applicability of mean-field approximations.

Findings

Identified two annealing stages below 600K and one above 900K.

Found that spatial correlation effects are insignificant at high damage doses.

Simulated defect recovery behaviors align with experimental observations.

Abstract

Based on the parameters from published ab-inito theoretical and experimental studies, and combining Molecular Dynamics (MD) and kinetic Monte Carlo (KMC) simulations, a framework of multi-scale modeling is developed to investigate the long-term evolution of displacement damage induced by heavy-ion irradiation in cubic silicon carbide. The isochronal annealing after heavy ion irradiation is simulated, and the annealing behaviors of total interstitials are found consistent with previous experiments. Two annealing stages below 600K and one stage above 900K are identified. The mechanisms for those recovery stages are interpreted by the evolution of defects. The influence of the spatial correlation in primary damage on defect recovery has been studied and found insignificant when the damage dose is high enough, which sheds light on the applicability of approaches with mean-field approximation to the long-term evolution of damage by heavy ions in SiC.