Metallurgical silicon is the starting material for production of polysilicon. Typically, the metallurgical silicon is reacted with either hydrogen chloride (HCl) or with silicon tetrachloride (SiCl4) and hydrogen (H2) to produce trichlorosilane (HSiCl3). The produced trichlorosilane is in the next step purified and decomposed to a high purity silicon called polysilicon. Elkem’s Silgrain® silicon provides enhanced selectivity and yield to polysilicon producers utilizing both these processes.