Solution growth method of SiC is assumed to be a promising technique to grow high quality SiC bulk crystal. Solution growth of SiC are based on the liquid phase growth from an incongruent melt composed of Si and C. Among various solution growth techniques, top seeded solution growth (TSSG) method for SiC has been widely studied for a next generation SiC growing technique. In TSSG method, the crystal growth on seed crystals is accomplished by the precipitation of solid SiC from C dissolved a Si melt on a seed crystal located at the top of the liquid. Because of the low solubility of C in liquid Si, SiC crystal growth on seed crystals using TSSG involves the use of a Si-rich Si-C solution. Therefore, in the TSSG method, high C solubility is required to increase the growth rate of SiC. Hence, there have been lots of studies how to increase the C solubility of Si melt. Eventually, several metallic solvents were proved to enhance the carbon solubility, so that the growth rate of SiC using TSSG were remarkably increased up to 2 mm/h. So, it is very optimistic to increase the thickness of grown crystal.

However, TSSG has critical issue to increase crystal thickness because the C is supplied from the graphite crucible which is also the reservoir of Si melt. As growing time goes, therefore, the crucible will be dissolved to Si melt and the dissolved carbon will be consumed to grow single crystalline SiC crystal. Eventually, the thickness of SiC grown layer will be limited the volume size of graphite crucible. The reduction of graphite crucible will bring about the change of temperature distribution in the solid and liquid inside the reactor. Mechanical failure during crystal growth could be happened.

Therefore, in this study, we applied a graphite block inside graphite crucible for elongate the growing time limit using graphite crucible for TSSG. Several graphite blocks with different design and materials properties were evaluated using finite element analysis using COMSOL multiphysics. The simulated results were then applied to the real experimental growth using small seed samples. Finally, the durability of graphite crucible and the crystal quality were comparatively evaluated with and without graphite blocks using several characterizations techniques.