Optimization of SiC single crystal growth via numerical simulation: Enhanced mass transport with graphite ring and block design

The silicon carbide (SiC) single crystal, serving as a critical material for high-power and high-temperature semiconductor devices, has consistently encountered the significant challenge of balancing growth rate with crystal quality during its fabrication process. This study employs finite element analysis within the STR Virtual Reactor simulation environment to examine the impact of optimizing the crucible’s internal structure through the introduction of a graphite ring and graphite blocks on mass transport and crystal quality. Simulation results demonstrate that the graphite ring can effectively suppress the recrystallization phenomenon on the surface of SiC raw powders, optimize gas-phase transport pathways, and consequently reduce the formation of carbon inclusions and defects. Although the graphite ring slightly decreases the growth rate, the incorporation of a cylindrical graphite block compensates for this reduction by enhancing thermal flux and thereby accelerating the growth process. The combined application of these two structural designs effectively optimizes mass transport while maintaining the growth rate, offering new insights into crucible design optimization and providing a novel technical approach for the large-scale production of high-quality SiC single crystals.