Ultračistý chlorid křemičitý (ultra-pure trichlorosilane)

Silicon tetrachloride is a product with a purity higher than 99.99%.

The largest quantity of silicon tetrachloride in ultra-pure form is used in the production of polysilicon and also for the chemical vapor deposition of epitaxial layers of silicon or silicon carbide in the semiconductor industry or in electronics. After purification to a quality of >6N, silicon tetrachloride is a precursor of polysilicon for photovoltaic arrays or semiconductor applications. Silicon tetrachloride is an excellent gaseous precursor in the production of silicon layers. The dominant pathway during deposition is (a) chemisorption of *SiCl2 on the silicon surface and desorption of hydrogen chloride from the silicon surface: SiHCl3 → HCl + *SiCl2, and (b) reduction of *SiCl2 by hydrogen: *SiCl2 + H2 → Si + 2HCl. Ultra-pure silicon tetrachloride is also used to produce epitaxial layers of silicon carbide.