Entries |
Document | Title | Date |
20090053124 | METHOD FOR PURIFICATION OF DISILICON HEXACHLORIDE AND HIGH PURITY DISILICON HEXACHLORIDE - The objective of the present invention is to provide a method for obtaining a high purity disilicon hexachloride by removing a silanol with good efficiency from a disilicon hexachloride material containing the silanol as an impurity. The purification method for disilicon hexachloride of the present invention comprises a process for contacting a disilicon hexachloride material containing disilicon hexachloride and a silanol as an impurity with an adsorbent material such as activated carbon to remove the silanol. The method may further comprise a distillation process. The above processes are preferably performed in an atmosphere of an inert gas. | 02-26-2009 |
20090092534 | PROCESSES FOR PURIFICATION OF SILICON TETRAFLUORIDE - Processes for purifying silicon tetrafluoride source gas by subjecting the source gas to one or more purification processes including: contacting the silicon tetrafluoride source gas with an ion exchange resin to remove acidic contaminants, contacting the silicon tetrafluoride source gas with a catalyst to remove carbon monoxide, by removal of carbon dioxide by use of an absorption liquid, and by removal of inert compounds by cryogenic distillation; catalysts suitable for removal of carbon monoxide from silicon tetrafluoride source gas and processes for producing such catalysts. | 04-09-2009 |
20090136407 | ISOTOPE ENRICHEMENT METHOD - An isotope enrichment method comprising the step of performing the isotope exchange between an aqueous solution containing at least two components each represented by the formula: H | 05-28-2009 |
20090274606 | PROCESS FOR PRODUCTION OF SILICON TETRAFLUORIDE, AND APPARATUS FOR THE PROCESS - Disclosed is a process for production of silicon tetrafluoride which can reduce the cost for the silicon tetrafluoride production and can also reduce the quantities of waste products produced in the process. Also disclosed is an apparatus for use for the process. The method comprises the steps of: (a) a high-silica fluorosilicic acid production step in which a raw material ( | 11-05-2009 |
20100008841 | Method for the Manufacture of Silicon Tetrachloride - The invention concerns a method for the manufacture of silicon tetrachloride by conversion of a mixture of finely divided and/or amorphous silicon dioxide, carbon and an energy donator with chlorine. Energy donators are metallic or silicon alloys such as silicon, ferrosilicon or calcium suicide. The addition of the donors effects a self-sustaining, exothermic reaction on one hand and a significant lowering of the reaction starting temperature on the other hand. | 01-14-2010 |
20100061911 | METHOD TO CONVERT SILICON POWDER TO HIGH PURITY POLYSILICON THROUGH INTERMEDIATE SiF4 - A process for the recovery of silicon includes providing silicon-containing solids recovered from a silicon manufacturing process, said recovered silicon-containing solids being substantially free of semiconductor dopants; converting the recovered silicon-containing solids into gaseous silicon forms; subjecting to purification by minimal distillation; collecting the gaseous silicon forms as a condensed liquid of silicon-containing compounds; and utilizing the silicon-containing compounds for silicon deposition. | 03-11-2010 |
20100129281 | A PROCESS FOR THE RECYCLING OF HIGH PURITY SILICON METAL - A process for the re-use of remainders or other residual Si of high purity silicon such as saw dust or kerf from manufacturing of solar cells wafers or semi-conductor devices, is characterized in that the dry kerf, chips and/or other residual Si from wafer production processes or semi-conductor devices is used as feedstock together with metallurgical grade silicon in a direct chlorination reactor ( | 05-27-2010 |
20100150808 | PROCESSES FOR PRODUCING SILICON TETRAFLUORIDE FROM FLUOROSILICATES IN A FLUIDIZED BED REACTOR - Processes for preparing silicon tetrafluoride by the thermal decomposition of an alkali or alkaline earth-metal fluorosilicate in a fluidized bed reactor. A portion of silicon tetrafluoride that is generated in the decomposition reaction may be recycled to the reactor and used as a fluidizing gas to suspend the fluorosilicate material. Alkali or alkaline earth-metal fluoride residue generated in the decomposition reaction may be discharged from the reactor and reacted with fluorosilicic acid to produce an alkali or alkaline earth-metal fluorosilicate that may be introduced to the reactor for further generation of silicon tetrafluoride. | 06-17-2010 |
20100189621 | PROCESS OF SILICON TETRAFLUORIDE GAS SYNTHESIS - A process of producing silicon tetrafluoride from fluoride containing feedstocks. The process calcines the fluoride containing feedstock and a silica containing feedstock before reacting the mixture with sulfuric acid to produce silicon tetrafluoride. The silicon tetrafluoride is scrubbed with sulfuric acid. Excess sulfuric acid is recycled to the process. The process demonstrates an economic and environmentally friendly way to produce high quality silicon tetrafluoride. | 07-29-2010 |
20100272625 | GECL4 AND/OR SICL4 RECOVERY PROCESS FROM OPTICAL FIBERS OR GLASSY RESIDUES AND PROCESS FOR PRODUCING SICL4 FROM SIO2 RICH MATERIALS - A method is provided for producing GeCl | 10-28-2010 |
20110150739 | METHOD FOR REMOVING BORON-CONTAINING IMPURITIES FROM HALOGEN SILANES AND APPARATUS FOR PERFORMING SAID METHOD - The invention relates to a method for reducing the content of boron-containing compounds in compositions I comprising at least one silicon halide, especially of chlorosilanes of the type HnSiCI4-n with n being equal to 0, 1, 2 or 3, by introducing a small amount of moisture into the composition I in a first step and separating the hydrolyzed boron- and/or silicon-containing compounds in a second step in such a way that a pre-purified composition II having a reduced boron content is obtained, wherein, in particular, the first and second steps can be run in at least one or more cycles. Also claimed is an apparatus for performing the method and an overall system into which this apparatus is integrated. | 06-23-2011 |
20110158882 | Methods For Producing Silicon Tetrafluoride - Methods for producing silicon tetrafluoride by acid digestion of fluoride salts of alkali metal or alkaline earth metal and aluminum, optionally, in the presence of a source of silicon; methods for producing silane that include acid digestion of by-products of silane production to produce silicon tetrafluoride. | 06-30-2011 |
20110305619 | Silicon Containing Halogenide, Method for Producing the Same, and Use of the Same - The invention relates to silicon containing halogenide obtained by thermal disintegration of halogenized polysilane, and a method for producing the silicon. The silicon has a halogenide content of 1 at %-50 at %. The invention further relates to the use of the silicon containing halogenide for purifying metallurgical silicon. | 12-15-2011 |
20110305620 | Method for producing halogenated oligomers and/or halogenated polymers of elements of the third to fifth main group - The invention relates to a method for producing halogenated oligomers and/or halogenated polymers of elements of the third to fifth main group, wherein the halogenated oligomers and/or halogenated polymers are synthesized from a first chain-forming agent and a second chain-forming agent in a plasma-chemical reaction. At least one of the two chain-forming agents is a halogen compound of an element of the third to fifth main group. | 12-15-2011 |
20120189525 | Contamination Free Compression of Corrosive Gas - A process for the synthesis of a high purity corrosive gas generated by decomposition of a precursor solid at high temperature deploys a dry vacuum pump and a compressor in series so that the corrosive gas is pressured as it fills storage containers. | 07-26-2012 |
20130115157 | CALCINING CHAMBER AND PROCESS - Solid materials capable of producing toxic and/or corrosive gases by thermal decomposition are heated in a stirred in a sealable crucible. The stirring rod is supported on a downward extending shaft using a combination of a lip seal or other mechanical seal and a ferro-fluidic seal or rotary feed through. The lip seal region is evacuated to reduce the chance that the small upward flow of corrosive gas will detrimentally react with components of the ferro-fluid. In a process for calcining sodium fluorosilicate to product silicon tetra-fluoride gas, the lip seal and ferro-fluidic seal regions are purged and/or blanked to prevent the absorption of water during an initial drying phase. A preferred embodiment of the process of synthesis of a high purity corrosive gas generated by decomposition of a precursor solid at high temperature deploys a dry vacuum pump and a compressor in series so that the corrosive gas is pressurized as it fills storage containers. Accordingly, the reaction of water with silicon tetra-fluoride to produce corrosive hydrogen fluoride gas is prevented. | 05-09-2013 |
20130272945 | Method for Producing Silicon Chloride from Silicon Sludge - Provided is a method for producing silicon chloride from silicon sludge by separating and recovering silicon carbide from waste silicon sludge generated during a semiconductor manufacturing process. With the method for producing silicon chloride from silicon sludge according to the present invention, oil components, iron, silicon that are contained in the silicon sludge may be removed, and silicon carbide may be selectively separated, thereby making it possible to produce high purity silicon chloride that may be used as a raw material for producing silica, silicon, or the like. | 10-17-2013 |
20140335006 | METHOD FOR PRODUCING TETRAHALOSILANES - A method produces tetrahalosilanes (SiX | 11-13-2014 |
20140341795 | Fluorspar/Iodide Process for Reduction, Purification, and Crystallization of Silicon - Method and apparatus for producing molten purified crystalline silicon from low-grade siliceous fluorspar ore, sulfur trioxide gas, and a metallic iodide salt. Method involves: (1) initially reacting silicon dioxide-bearing fluorspar ore and sulfur trioxide gas in sulfuric acid to create silicon tetrafluoride gas and fluorogypsum; (2) reacting the product gas with a heated iodide salt to form a fluoride salt and silicon tetraiodide; (3) isolating silicon tetraiodide from impurities and purifying it by washing steps and distillation in a series of distillation columns; (4) heating the silicon tetraiodide to its decomposition temperature in a silicon crystal casting machine, producing pure molten silicon metal ready for crystallization; and pure iodine gas, extracted as liquid in a cold-wall chamber. The system is batch process-based, with continuous elements. The system operates largely at atmospheric pressure, requiring limited inert gas purges during batch changes. | 11-20-2014 |
20140363362 | MANUFACTURING METHOD OF HIGH-PURITY CHLOROPOLYSILANE - [Problem] Chloropolysilane having a low metallic impurity concentration has been required to be obtained in order to be used for semiconductor applications. However, it is difficult by distillation to remove impurities such as a titanium compound having a vapor pressure close to that of chloropolysilane and an aluminum compound having a sublimating property. Meanwhile, when the content of metallic impurities such as aluminum and titanium reduces in metallic silicon that is a raw material, chlorination reaction is less likely to occur unless a reaction temperature is raised and that causes equipment to be restricted. It is found that a chlorination reaction can be carried out at a relatively low temperature by heating a mixture of granular metallic silicon and metallic copper or a copper compound in an inert atmosphere even when the metallic silicon has a high purity and does not contain aluminum and titanium and that chloropolysilane of high purity can be obtained by further adding metallic silicon as needed after the chlorination reaction is started. | 12-11-2014 |
20150023861 | ALTERNATIVE METHODS FOR THE SYNTHESIS OF ORGANOSILICON COMPOUNDS - A method of forming chloro-substituted silanes from the reaction of an alkoxysilane with a chlorinating agent in the optional presence of a catalyst is provided. More specifically, chloro-substituted silanes, including but not limited to silicon tetrachloride, are formed by reacting a chlorinating agent, such as thionyl chloride, with an alkylalkoxysilane having the formula (R′O) | 01-22-2015 |