The upgraded technology of polycrystalline silicon.
The basis of Russia’s modernized technology of polycrystalline silicon on the method of hydrogen reduction of silicon from trichlorosilane. Its feature is the application of high-performance equipment and recirculation circuits with the aim of maximum utilization of the starting materials to obtain the target products.
The technology of obtaining polycrystalline silicon is “Siemens-process”, which in world practice is the main way to obtain material. The Russian technology of reception of polycrystalline silicon is upgraded, it provides the best performance for silicon production “electronic” or “Sunny” quality.
The basis of Russia’s upgraded technology on the method of hydrogen reduction of silicon from trichlorosilane. Its feature is the application of high-performance equipment and recirculation circuits with the aim of maximum utilization of the starting materials to obtain the target products.
The upgraded technology of polycrystalline silicon on an industrial scale includes the following main process stages and departments:
– the synthesis of hydrogen chloride from hydrogen and chlorine,
– synthesis of trichlorosilane by hydrochlorination of silicon,
– pyleochistka gas mixture after synthesis of trichlorosilane,
– separation and purification of CHLOROSILANES (rectification),
– hydrogen recovery silicon using a gas mixture: a trichlorosilane – hydrogen,
– hydrogenation of silicon tetrachloride to trichlorosilane, using vapor-gas mixture: silicon tetrachloride – hydrogen,
– condensation and regeneration of steam-gas mixture formed in the synthesis of trichlorosilane, as well as in the processes of hydrogen recovery and hydrogenation,
– decontamination and disposal of liquid, solid and gaseous waste,
– quality control and certification of raw materials, intermediate and finished products,
– preparation of polysilicon for implementation as commodity products (chopping, packing, etc.).
The semiconductor purity polysilicon is the main raw material for the manufacture of semiconductor technology products, including discrete and integrated microelectronic devices, solar cells, solar panels and solar panel.
|Level acceptors||0,1 – 0,05 ppba (p – type, ρ = 3000 – 5000 Ω*cm or above)|
|Level donors||0.1 to 0.15 ppba (n – type, ρ = 300 – 500 Ω*cm or above)|
|The carbon content||Of 0.1 – 0.15 ppma|
|The total content of metals in the volume of (Fe, Cu, Ni, Cr)||5 – 10 ppba|
|The total content of metal on the surface of (Fe, Cu, Ni, Cr)||≤5 ppba|