Patent RU-2280010-C1 (RU)
Inventor: ELJUTIN ALEKSANDR VJACHESLAVOV
IPC: C01B33/107
Filed: 2004-12-10
Granted: 2006-07-20
Abstract: FIELD: chemical industry; microelectronics; methods of production of trichlorosilane for manufacture of the semiconducting materials. 
     SUBSTANCE: the invention is pertaining to the method of the semiconducting materials and may be used in production of semiconducting silicon used for manufacture of trichlorosilane being the starting crude for production of the semiconducting silicon. The method of production of trichlorosilane includes: synthesis of hydrogen chloride; synthesis of trichlorosilane with production of trichlorosilane in the steam-gas mixture containing also silicon tetrachloride, hydrogen and hydrogen chloride; condensation of chlorosilanes with separation of hydrogen and hydrogen chloride; rectification of the produced condensate with separation of trichlorosilane and silicon tetrachloride and with rectification of trichlorosilane and silicon tetrachloride. The synthesis of trichlorosilane is conducted at the pressure of 3.0-5.0 atm in the boiling layer by hydrochlorination of silicon with the particles size fineness of 100-1000 microns at the linear speed of the formed steam-gas mixture stream in the middle part of the reaction zone of the reactor of 0.10-0.30 m\s and the height of the boiling layer of 3.5-5.5 m. The steam-gas mixture is sequentially subjected to the "dry" and "wet" dust purifications. The "Wet" dust purification is conducted in three phases: at the first phase the steam-gas mixture stream is passing through the hollow column sprinkled by chlorosilanes, at the second phase the steam-gas mixture stream is subjected to bubbling during its passing through the bubble-type still filled with chlorosilanes, at the third phase the steam-gas mixture stream is subjected to the passage through the bubble column sprinkled by chlorosilanes. The condensation of the steam-gas mixture is conducted with the separate production of hydrogen, hydrogen chloride and condensate of chlorosilanes. The produced hydrogen is sent back to the synthesis of the hydrogen chloride, and hydrogen chloride - to the synthesis of trichlorosilane. The silicon tetrachloride produced after separation of condensate of chlorosilanes is subjected to purification from the high-boiling impurities by rectification. Trichlorosilane is in series subject to the "reaction" rectification, settling-out and direct to the deep purification by rectification for separation of the low- boiling impurities with the factor of separation of the limiting impurities in the system with trichlorosilane of 1.20 - 1.40 and for separation of the high-boiling impurities with the factor of separation of the limiting impurities in the system with trichlorosilane of 1.10 - 1.20. All the processes of the rectification are conducted at the pressure of the top part of the columns of 1.5-4.0 atm. The solid and liquid wastes of the process of production of trichlorosilane are decontaminated, transforming them into the chemically safe form. The technical result of the invention is the increased purity of the produced trichlorosilane, improvement of the technical and economic indices of the production process, provision of the high purity of the main by-product - silicon tetrachloride. 
     EFFECT: the invention ensures the increased purity of the produced trichlorosilane, improvement of the technical and economic indices of the production process, provision of the high purity of the main by-product - silicon tetrachloride. 
     13 cl, 2 tbl, 1 dwg, 1 ex