Numerical Simulation of the Formation Process of Overhanging Structures in SiC Solution Growth to Suppress Solvent Inclusion

This research presents a study utilizing the phase field model to investigate the formation process of overhanging structures during silicon carbide (SiC) solution crystal growth. The model integrates phase field and diffusion field equations to simulate the evolution of steps and solute diffusion. The simulation successfully replicated the formation process of the overhanging structure. It revealed that the formation mechanism of overhanging inclusions is insufficient solute diffusion, and the difference in carbon flux between the upper and lower parts of the macroscopic step leads to the formation of overhanging structures and inclusions. Factors influencing overhanging formation are explored, such as the solution flow direction and step height. The results show that antiparallel solution flow and optimal step heights can suppress the overhanging formation. This study guides suppressing the formation of the overhanging structure inclusions and can be applied to various crystals beyond SiC.