Patent application number | Description | Published |
20090057129 | METHOD FOR PRODUCING TRICHLOROSILANE AND METHOD FOR PRODUCING POLYCRYSTALLINE SILICON - A hydrogenation reaction vessel makes STC-containing substance react with hydrogen to convert the substance into TCS. A low boils removal column separates a chlorosilane distillate discharged from a hydrogenation reaction vessel into TCS and a mixture distillate containing hyper-hydrogenated chlorosilane, and circulates the mixture distillate containing hyper-hydrogenated chlorosilane to the hydrogenation reaction vessel. The mixture distillate containing the hyper-hydrogenated chlorosilane separated in the low boils removal column is circulatingly supplied to the hydrogenation reaction vessel. Accordingly, low boils by-product conventionally wasted is circulated and recycled in the process, which results in enhancing a yield of TCS production. | 03-05-2009 |
20090060817 | METHOD FOR PRODUCING TRICHLOROSILANE - A by-product mixture produced in a process for producing polycrystalline silicon is made to react with chlorine to form tetrachlorosilane (STC) distillate in a chlorination reaction vessel, and the tetrachlorosilane (STC) distillate is made to react with hydrogen in a hydrogenation reaction vessel to be converted into trichlorosilane (TCS). In the chlorination step, methyl chlorosilanes having boiling points close to TCS are hyper-chlorinated to be converted into hyper-chlorinated methyl chlorosilanes having higher boiling points, which facilitates the hyper-chlorinated methyl chlorosilanes to be separated into high concentration, and inhibits carbon from contaminating the polycrystalline silicon. A donor/acceptor eliminator is provided in the circulation cycle for producing TCS, and accordingly there is no need to take out a by-product produced in the process for producing TCS to the outside of the system, which can highly purify the TCS. | 03-05-2009 |
20090060820 | METHOD FOR PRODUCING TRICHLOROSILANE AND METHOD FOR PRODUCING POLYCRYSTALLINE SILICON - The present invention includes a step of separating an effluent produced in a hydrogenation step of making tetrachlorosilane (STC) react with hydrogen into trichlorosilane (TCS), into a chlorosilane fraction containing a hydrocarbon and a TCS fraction, and a chlorination step of making the chlorosilane fraction containing the hydrocarbon react with chlorine to form STC and a substance containing a chlorinated hydrocarbon, wherein the effluent containing STC produced in the chlorination step is circulated to the hydrogenation step. In the chlorination step, the chlorosilane fraction containing a hydrocarbon (capable of containing hyper-hydrogenated chlorosilanes) having a boiling point close to TCS is hyper-chlorinated to be converted and acquire a higher boiling point, which facilitates the hyper-chlorinated chlorosilanes and the hyper-chlorinated hydrocarbons to be separated into high concentration, and increases the purity of TCS to be finally obtained. | 03-05-2009 |
20090060822 | METHOD FOR PRODUCING POLYCRYSTALLINE SILICON - A by-product mixture produced when polycrystalline silicon is deposited on a base material in a CVD reactor is made to react with chlorine to form a tetrachlorosilane (STC) effluent in a chlorination reaction vessel, and the tetrachlorosilane (STC) distillate is made to react with hydrogen in a hydrogenation reaction vessel to be converted into trichlorosilane (TCS). In the chlorination step, poly-silane contained in the above described by-product mixture can be efficiently recycled as a raw material for producing the polycrystalline silicon, which can enhance a yield of the production process. In addition, in the chlorination step, methyl chlorosilanes having boiling points close to TCS are hyper-chlorinated to be converted into hyper-chlorinated methyl chlorosilanes having higher boiling points, which facilitates the hyper-chlorinated methyl chlorosilanes to be separated into high concentration, and reduces carbon contamination of the polycrystalline silicon. | 03-05-2009 |
20120121493 | METHOD FOR PURIFYING CHLOROSILANES - The present invention provides a method for obtaining high purity chlorosilanes from chlorosilanes containing boron impurities and phosphorus impurities. On the basis of the finding that solid by-product formation in the purification of chlorosilanes by adding an aromatic aldehyde results from a catalytic reaction by iron ions or rust-like iron, a Lewis base having a masking effect is added to chlorosilanes. Examples of the Lewis base include a divalent sulfur-containing compound and an alkoxysilane. The divalent sulfur-containing compound is preferably a compound represented by the formula: R—S—R′ (wherein R is a hydrocarbon group or a carbonyl group; and the sum of the carbon atoms in R and R′ is 7 or more), and the alkoxysilane is preferably a compound represented by the formula: R | 05-17-2012 |
20120237429 | REACTOR FOR PRODUCING POLYCRYSTALLINE SILICON, SYSTEM FOR PRODUCING POLYCRYSTALLINE SILICON, AND PROCESS FOR PRODUCING POLYCRYSTALLINE SILICON - An inner wall | 09-20-2012 |