Very large purity silicon for semiconductors is received utilizing the Siemens system; the silicon is reacted to make trichlorosilane, which is to start with purified by distillation, then reacted with purified hydrogen on high purity silicon rods at 1150 oC to generate large purity, polycrystalline silicon with hydrochloric acid byproduct. https://busbarmachine71470.timeblog.net/72288476/the-basic-principles-of-silicon-carbide-crucible