Heat and mass transfer characteristics of three-dimensional bell-shaped polysilicon chemical vapor deposition reactor

Abstract

Polysilicon, the crucial material of photovoltaic field, is commonly produced in a Siemens chemical vapor deposition (CVD) reactor with a complex physical and chemical phenomenon included inside as well as complicated geometry structure. In order to study the performance of silicon CVD reactor, a three-dimensional bell-shaped reactor model with 24 rods is constructed and verified to investigate the heat and mass transfer performance inside. The distributions of velocity, temperature, complex concentrations of six main components, silicon deposition rate, and energy of the reduction furnace at high and low inlet velocities are analyzed in detail. Results show that high inlet velocity is more conductive to obtain uniform distributions of velocity, temperature, complex concentration, and silicon deposition rate, leading to better silicon CVD performance. The inner rods are easier to collapse than the outer rods. In addition, radiation loss is the main energy consumption in the silicon reduction furnace and accounts for more than 60% of the total energy consumption. The convective heat transfer, chemical reaction heat, proportion of convective heat, and the proportion of chemical reaction heat increase with the rise in inlet velocity due to a fully developed flow field.