The Effect of Crucible Rotation and Crucible Size in Top-Seeded Solution Growth of Single-Crystal Silicon Carbide

The top-seeded solution growth method is a promising technique for growing high-quality silicon carbide single crystal. Some inherent issues in this growth process, such as morphological instability, polycrystalline growth, and low growth rate, should be clarified. A high temperature difference between the seed and the crucible wall in this system is needed to enhance growth. However, such a high temperature gradient makes the radial growth rate profile non-uniform due to the effect of Marangoni convection below the seed crystal, which leads to poor crystal quality. In the present work, the effects of crucible size and crucible rotation are numerically investigated to minimize the effect of Marangoni convection. The possibilities of the occurrence of growth-rate non-uniformity and undesired impurity incorporation are examined. A smaller crucible (in radius) leads to a more uniform growth rate profile. However, it gives rise to a higher possibility of impurity incorporation. It is also predicted that crucible rotation is ineffective in suppressing the Marangoni flow near the seed edge. This leads to a flow stagnation in the center of the melt, and consequently, it does not enhance the carbon transport below the seed. It also does not reduce the possibility of undesired impurity incorporation.