Optimization Of The Raw Material Input Molar Ratio On The Carbothermal Production Of Solar-grade Silicon

With the fast growth of solar cells market, it is strongly required to improve the fabrication process of solar-grade silicon, which is the base material for more than 93% of solar cells technology. Conventionally, solar-grade silicon is produced via the direct reduction of silica stone to metal-grade silicon by arc furnace followed by the Siemens method with chemical treatment and hydrogen. However, in this technique, a low yield of solar-grade silicon is obtained with high energy cost due to its multiple complex processes. Meanwhile, it has been turned out that, the direct reduction process from silica sand to solar-grade silicon via induction furnace simplify the fabrication process with low energy and cost consumption with higher yield. In this study, the optimum partial pressure and temperature conditions of this process were based on the stability phase diagram for reduction reaction process. Using the simulation results, we succeeded to increase the reduction yield by ten times.