But care should be taken to suppress the other reaction occurring simultaneously (Si + C SiC), which will not only reduce the yield of Si, but clog up the furnace by SiC.

The 9N purity (99.9999999) silicon is made essentially in three steps:

Liquid Si reacts with all substances and is a universal solvent. This makes crystal growth from liquid Si somewhat difficult. Si is converted to SiHCl₃ via the reaction at around 300°C

Si (s) + 3HCl (g) SiHCl₃ (g) + H₂ (g) + heat

The resulting Trichlorosilane is already much purer than the raw Si; it is a liquid with a boiling point of 31.8°C.

The SiHCl₃ is further distilled, resulting in extremely pure Trichlorosilane.

Finally, high-purity Si is produced by a "Chemical Vapor Deposition" (CVD) process (discussed in later sections) .