Ceramic composite device for water removal in the preparation of dimethyldimethoxysilane and method of manufacturing thereof

Abstract

The application discloses a ceramic composite device for water removal in the preparation of dimethyldimethoxysilane and a manufacturing method thereof. The ceramic composite device is internally hollow and cylindrical, is located in a distillation outlet gas pipeline at the rear end of a dimethyldimethoxysilane purification device, and the outer diameter of the ceramic composite device is in sealing matching with the inner diameter of the distillation outlet gas pipeline. The ceramic composite device is composed of a hollow porous ceramic shell and a water-absorbing filler inside the ceramic shell, and the gas permeation rate of the porous ceramic shell is not less than 90%. The application has the characteristics of high gas permeation rate, good water removal, no increase of impurities, stability and controllability, and easy maintenance.

Description

Technical Field

[0001] This invention relates to an apparatus for manufacturing high-purity semiconductor dopant dimethyldimethoxysilane, and more particularly to a method for manufacturing a ceramic composite apparatus for removing water during the preparation of dimethyldimethoxysilane. Background Technology

[0002] Semiconductor doping is used to improve the electrical performance of semiconductor devices. Many electrical properties of semiconductors are related to the concentration of impurities in the dopant.

[0003] Pure semiconductors generate charge carriers and conduct electricity through intrinsic excitation. However, the number of charge carriers generated by intrinsic excitation alone is very small and easily affected by external factors such as temperature. Doping with appropriate trivalent or pentavalent elements can generate other charge carriers in addition to intrinsic excitation. There are two main doping techniques for semiconductors: high-temperature (thermal) diffusion and ion implantation. The impurities introduced are mainly of two types: the first type is acceptor or donor impurities that provide charge carriers (such as B, P, and As in Si); the second type is heavy metal impurities that generate recombination centers (such as Au in Si).

[0004] However, high-end semiconductor products have extremely high requirements for dopants, and dimethyldimethoxysilane (DMDMOS) is generally prepared by distillation purification process. In current technology, dimethyldimethoxysilane (DMDMOS) undergoes a significant hydrolysis reaction with water during heating, so controlling the water content in the overall purification system is crucial.

[0005] Currently, no existing technology can solve the above problems. What is needed is a method for manufacturing a ceramic composite device for dehydration in the preparation of dimethyldimethoxysilane that has high gas throughput, good water removal performance, does not increase impurities, is stable and controllable, and is easy to maintain. Summary of the Invention

[0006] The present invention aims to provide a method for manufacturing a ceramic composite device for dehydration in the preparation of dimethyldimethoxysilane, which has high gas throughput, good water removal performance, does not increase impurities, is stable and controllable, and is easy to maintain.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a ceramic composite device for dehydration during the preparation of dimethyldimethoxysilane, wherein the ceramic composite device is a hollow cylinder located within the distillation pipeline system of the dimethyldimethoxysilane purification device, and the outer diameter of the ceramic composite device forms a sealed match with the inner diameter of the distillation outlet pipeline; the ceramic composite device consists of a hollow porous ceramic shell and an internal water-absorbing filler, wherein the gas throughput of the porous ceramic shell is not less than 90%; The manufacturing method for preparing the above-mentioned ceramic composite device is characterized by comprising the following stages: S1: Raw Material Preparation ① Raw material preparation: Prepare sufficient activated carbon granules with a particle size of 0.2mm-0.5mm, alumina powder with a particle size of 0.05mm-0.1mm, alumina powder with a particle size of 1μm-2μm, isobutylene maleic anhydride copolymer, polymethyl methacrylate, aluminum fluoride powder, aluminum hydroxide, clay, polyvinyl alcohol, coconut shell charcoal, and glucose. S2: Preparation of ceramic support shell ① By weight, prepare 50-55 parts of alumina powder with a particle size of 0.05mm-0.1mm, 15-20 parts of alumina powder with a particle size of 1μm-2μm, 11-12 parts of aluminum fluoride powder, 16-17 parts of aluminum hydroxide, 0.8-1.2 parts of clay, 13-15 parts of coconut shell charcoal, and 8-10 parts of polyvinyl alcohol; ② After mixing the raw materials prepared in step ① evenly, fill the mold corresponding to the support shell with a hollow cavity as required by the design, sinter and remove the glue. The process parameters are: sintering temperature 1480℃-1500℃, holding time 130min-150min, to make a porous ceramic support shell. S3: Preparation of absorbent filler ① Under normal pressure, activated carbon particles are mixed with a 5% nitric acid aqueous solution at a mass ratio of 1:(18-23), and the mixture is heated to 75℃-80℃ and reacted for 4 hours. The activated carbon particles are filtered out, washed with distilled water, and then dried. The treated activated carbon particles are then mixed with a 10% sodium hydroxide solution at a mass ratio of 1:(8-12) and treated in a hydrothermal reactor at a reaction temperature of 215℃-220℃ for 8-10 hours. The reacted activated carbon particles are filtered out, washed with distilled water until the pH is neutral, and then dried to obtain surface-activated activated carbon particles. ② The surface-activated carbon particles obtained in step ① are treated with a glucose coating process. The specific parameters of the treatment are: the amount of glucose coating the activated carbon particles is 12%-14%, the carbonization temperature is 780℃-790℃, and the degree of carbonization is not less than 98%, so as to obtain glucose-coated activated carbon particles. S4: Ceramic Composite Device ① Fill the hollow cavity of the porous ceramic support shell obtained in step S2 ② with the glucose-coated activated carbon particles obtained in step S3 ② to obtain the desired ceramic composite device.

[0008] Compared with the prior art, the present invention has the following advantages due to the adoption of the above technical solutions: (1) This invention is essentially the product of the applicant’s targeted efforts to overcome the pain points and difficulties encountered in the long-term preparation of high-purity dopants. The biggest problem encountered by the applicant in the preparation of high-purity (7N grade, that is, purity above 99.99999%) dimethyldimethoxysilane is that dimethyldimethoxysilane is very easy to hydrolyze when it is in contact with water at high temperature. Therefore, water in the system, even water at the micro-molecular level, will have a significant impact on the purity of the final product. Moreover, this situation is more prevalent when the product purity is higher. The simple water removal device specially developed in this invention can effectively solve this problem and help the applicant improve the product purity to 8.5N grade or even 9N grade.

[0009] (2) The ceramic shell of the present invention is in fact a porous structure that does not impede gas flow, and its purpose is to provide structural support for the filling material inside. Through various tests, the applicant found that the filling material purified by the activated carbon of the present invention and covered with monosaccharide carbonization is the material with the best water removal effect without affecting the purity of the product.

[0010] Therefore, the present invention has the characteristics of high gas throughput, good water removal, no increase in impurities, stable and controllable operation, and easy maintenance. Detailed Implementation

[0011] Example

[0012] A ceramic composite device for dehydration in the preparation of dimethyldimethoxysilane is disclosed. The device is a hollow cylinder located within the distillation piping system of the dimethyldimethoxysilane purification apparatus. The outer diameter of the ceramic composite device forms a sealed match with the inner diameter of the distillation outlet pipe. The ceramic composite device consists of a hollow porous ceramic shell and an internal water-absorbing filler, wherein the gas throughput of the porous ceramic shell is not less than 90%. The manufacturing method for preparing the above-mentioned ceramic composite device is characterized by comprising the following stages: S1: Raw Material Preparation ① Raw material preparation: Prepare sufficient activated carbon granules with a particle size of 0.2mm-0.5mm, alumina powder with a particle size of 0.05mm-0.1mm, alumina powder with a particle size of 1μm-2μm, isobutylene maleic anhydride copolymer, polymethyl methacrylate, aluminum fluoride powder, aluminum hydroxide, clay, polyvinyl alcohol, coconut shell charcoal, and glucose. S2: Preparation of ceramic support shell ① By weight, prepare 50-55 parts of alumina powder with a particle size of 0.05mm-0.1mm, 15-20 parts of alumina powder with a particle size of 1μm-2μm, 11-12 parts of aluminum fluoride powder, 16-17 parts of aluminum hydroxide, 0.8-1.2 parts of clay, 13-15 parts of coconut shell charcoal, and 8-10 parts of polyvinyl alcohol; ② After mixing the raw materials prepared in step ① evenly, fill the mold corresponding to the support shell with a hollow cavity as required by the design, sinter and remove the glue. The process parameters are: sintering temperature 1480℃-1500℃, holding time 130min-150min, to make a porous ceramic support shell. S3: Preparation of absorbent filler ① Under normal pressure, activated carbon particles are mixed with a 5% nitric acid aqueous solution at a mass ratio of 1:(18-23), and the mixture is heated to 75℃-80℃ and reacted for 4 hours. The activated carbon particles are filtered out, washed with distilled water, and then dried. The treated activated carbon particles are then mixed with a 10% sodium hydroxide solution at a mass ratio of 1:(8-12) and treated in a hydrothermal reactor at a reaction temperature of 215℃-220℃ for 8-10 hours. The reacted activated carbon particles are filtered out, washed with distilled water until the pH is neutral, and then dried to obtain surface-activated activated carbon particles. ② The surface-activated carbon particles obtained in step ① are treated with a glucose coating process. The specific parameters of the treatment are: the amount of glucose coating the activated carbon particles is 12%-14%, the carbonization temperature is 780℃-790℃, and the degree of carbonization is not less than 98%, so as to obtain glucose-coated activated carbon particles. S4: Ceramic Composite Device ① Fill the hollow cavity of the porous ceramic support shell obtained in step S2 ② with the glucose-coated activated carbon particles obtained in step S3 ② to obtain the desired ceramic composite device.

[0013] The above description of the disclosed embodiments is merely intended to enable those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A ceramic composite device for dehydration during the preparation of dimethyldimethoxysilane, characterized in that: The ceramic composite device is a hollow cylinder located within the distillation piping system of the dimethyldimethoxysilane purification unit. The outer diameter of the ceramic composite device and the inner diameter of the distillation outlet pipe form a sealed match. The ceramic composite device consists of a hollow porous ceramic shell and an internal water-absorbing filler, wherein the gas throughput of the porous ceramic shell is not less than 90%. The manufacturing method for preparing the above-mentioned ceramic composite device is characterized by comprising the following stages: S1: Raw Material Preparation ① Raw material preparation: Prepare sufficient activated carbon granules with a particle size of 0.2mm-0.5mm, alumina powder with a particle size of 0.05mm-0.1mm, alumina powder with a particle size of 1μm-2μm, isobutylene maleic anhydride copolymer, polymethyl methacrylate, aluminum fluoride powder, aluminum hydroxide, clay, polyvinyl alcohol, coconut shell charcoal, and glucose. S2: Preparation of ceramic support shell ① By weight, prepare 50-55 parts of alumina powder with a particle size of 0.05mm-0.1mm, 15-20 parts of alumina powder with a particle size of 1μm-2μm, 11-12 parts of aluminum fluoride powder, 16-17 parts of aluminum hydroxide, 0.8-1.2 parts of clay, 13-15 parts of coconut shell charcoal, and 8-10 parts of polyvinyl alcohol; ② After mixing the raw materials prepared in step ① evenly, fill the mold corresponding to the support shell with a hollow cavity as required by the design, sinter and remove the glue. The process parameters are: sintering temperature 1480℃-1500℃, holding time 130min-150min, to make a porous ceramic support shell. S3: Preparation of absorbent filler ① Under normal pressure, activated carbon particles are mixed with a 5% nitric acid aqueous solution at a mass ratio of 1:(18-23), and the mixture is heated to 75℃-80℃ and reacted for 4 hours. The activated carbon particles are filtered out, washed with distilled water, and then dried. The treated activated carbon particles are then mixed with a 10% sodium hydroxide solution at a mass ratio of 1:(8-12) and treated in a hydrothermal reactor at a reaction temperature of 215℃-220℃ for 8-10 hours. The reacted activated carbon particles are filtered out, washed with distilled water until the pH is neutral, and then dried to obtain surface-activated activated carbon particles. ② The surface-activated carbon particles obtained in step ① are treated with a glucose coating process. The specific parameters of the treatment are: the amount of glucose coating the activated carbon particles is 12%-14%, the carbonization temperature is 780℃-790℃, and the degree of carbonization is not less than 98%, so as to obtain glucose-coated activated carbon particles. S4: Ceramic Composite Device ① Fill the hollow cavity of the porous ceramic support shell obtained in step S2 ② with the glucose-coated activated carbon particles obtained in step S3 ② to obtain the desired ceramic composite device.