Silicon carbide (SiC) substrates can be used to fabricate electronic devices and circuits which can function under extreme high-temperature, high-power, high-frequency conditions. The bulk growth of SiC single crystal by physical vapor transport (PVT) technique (modified Lely method) involves sublimation of a SiC powder charge, mass transfer through an inert gas environment, and condensation on a cold substrate seed. The SiC vapor deposits on the seed which has a lower temperature than the powder charge, and the SiC single crystal grows. Control of mass transfer and temperature distribution in the furnace with an extremely high temperature is critical to the quality of grown SiC single crystal. Modeling of the growth process is important for the design of efficient growth furnaces and reduction of micropipes and defect density in the grown crystal. A system model for SiC growth by PVT method is developed here that incorporates the radio frequency (RF) heating, and radiative and conductive heat transfer in the growth system. The generated heat power by RF heating of the graphite susceptor is calculated by solving the electromagnetic field. It is found that the radiation heat transfer plays a dominant role under high temperature and low-pressure conditions.
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