Molecular dynamics simulation of competitive crystal growth of in SiC with different nuclei: Temperature-dependent crystallization and defect formation

Abstract

Silicon carbide (SiC), a third-generation semiconductor distinguished by its wide bandgap, superior thermal conductivity, and exceptional electron saturation velocity, has become indispensable for aerospace and defense systems requiring extreme operational reliability. Optimizing SiC's crystalline perfection is critical for high-power devices, necessitating atomic-scale insights into its growth thermodynamics. This study conducted large-scale molecular dynamics simulations to elucidate polytype-specific crystallization mechanisms in pure SiC melts across 2800–3250 K. Radial distribution function analysis, time-resolved crystallization kinetics, and defect visualization revealed temperature-dependent growth regimes: low-temperature conditions exhibited nucleation suppression, while high-temperature regimes promoted competitive growth between cubic (3C–SiC) and hexagonal (4H–SiC) polytypes, highlighting the importance of temperature control in optimizing crystal quality. This study enhances our understanding of the crystallization process of SiC and provides theoretical insights for the production of high-performance power semiconductors.