Numerical simulation of heat distribution of silicon carbide growth by PVT method with inner rod

Abstract

The physical vapor transport (PVT) method has been widely used in the growth of silicon carbide single crystals. In designing the growth system, effective thermal management is crucial, particularly regarding the temperature of the growth surface and the horizontal and vertical temperature gradients. In this paper, an inner rod positioned along the central axis of the crucible to optimize thermal field through numerical simulations. The results show that the introduction of the inner rod reduces the horizontal temperature difference of the growth surface from nearly 80 °C to less than 10 °C, significantly minimizing the bulging of the growth crystals. Additionally, simulations were performed to examine the effects of varying the radius and height of the inner rod, as well as the radius of the bottom graphite holder, with findings discussed in detail. This study provides a theoretical method for the growth of high-quality, low-stress 4H-SiC crystals with smooth surfaces. It also provides a reference for the growth of 3C-SiC from small distance of material source to seed by sublimation epitaxy.