Pretty high purity silicon for semiconductors is obtained using the Siemens procedure; the silicon is reacted to supply trichlorosilane, and that is to start with purified by distillation, then reacted with purified hydrogen on superior purity silicon rods at 1150 oC to generate superior purity, polycrystalline silicon with hydrochloric acid https://damienuutqp.blognody.com/40473403/5-essential-elements-for-sic-heating-element