A process for the production of an electronic grade bis-tert-butylamino-silane

Abstract

The application discloses a kind of electronic grade di-tert-butyl amino-silane manufacturing method, which is sequentially provided with raw material reaction system, centrifugal double-layer membrane separation device, triple nitrogen gas protection rectifying kettle assembly and three-waste recovery treatment device from feeding to discharging in the manufacturing device used in the manufacturing method;Solid-liquid separation device and reactant detection device are arranged between the raw material reaction system and the centrifugal double-layer membrane separation device;Microporous filter membrane with filter pore size 1 μm and nanofiltration membrane with pore size 0.001 μm-0.002 μm are sequentially arranged from inside to outside in the centrifugal double-layer membrane separation device;The intermediate layer of the centrifugal double-layer membrane separation device is communicated with the triple nitrogen gas protection rectifying kettle assembly, and the intermediate layer and the triple nitrogen gas protection rectifying kettle assembly are provided with pre-purified product detection device;The gas and solid discharged from the triple nitrogen gas protection rectifying kettle assembly are all introduced into the three-waste recovery treatment device.The production process of the application is environmentally friendly, the types of raw materials are simple, the emissions are less, and the product purity is high.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for manufacturing electronic-grade material for semiconductor, in particular to a method for manufacturing electronic-grade bis-tert-butylamino-silane. BACKGROUND

[0002] Bis-tert-butylamino-silane is a kind of silane coupling agent (BTBAS), which is a precursor of chemical vapor liquid chemistry and can be used to deposit uniform silicon nitride and prepare silicon nitride film, semiconductor devices and shallow trench isolation film.

[0003] In the prior art, the production of bis-tert-butylamino-silane often produces environmentally incompatible gas by-products and a large amount of impurity slurry waste, which is difficult to clean up in the system. The main reason for this problem is that the production equipment of bis-tert-butylamino-silane, especially the high-purity electronic-grade bis-tert-butylamino-silane production equipment, has low integration and complex process, resulting in more emissions and difficult to handle. At the same time, due to the low integration of production technology and process, the actual product purity is difficult to meet the needs of higher quality semiconductors.

[0004] Therefore, there is a need for a method for manufacturing electronic-grade bis-tert-butylamino-silane with an environmentally friendly production process, simple raw material types, less emissions, and high product purity. SUMMARY

[0005] The present application aims to provide a method for manufacturing electronic-grade bis-tert-butylamino-silane with an environmentally friendly production process, simple raw material types, less emissions, and high product purity.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a method for manufacturing electronic-grade bis-tert-butylamino-silane, which is matched with the following manufacturing apparatus, wherein the manufacturing apparatus is arranged in the order of feeding to discharging, including a raw material reaction system, a centrifugal double-layer membrane separation device, a triple nitrogen-protected distillation vessel assembly, and a waste recovery and treatment device; wherein a solid-liquid separation device and a reactant detection device are arranged between the raw material reaction system and the centrifugal double-layer membrane separation device; the centrifugal double-layer membrane separation device is arranged from the inside to the outside with a commercially available microporous filter membrane with a pore size of 1 μm and a nanofiltration membrane with a pore size of 0.001 μm-0.002 μm; the intermediate product layer of the centrifugal double-layer membrane separation device is connected to the triple nitrogen-protected distillation vessel assembly. A pre-purified product detection device is installed between the yield layer of the centrifugal double-layer membrane separator and the triple nitrogen-protected distillation vessel assembly; the centrifugal double-layer membrane separator is also equipped with a core residue conveying device, which is matched with the waste recovery and treatment device; the triple nitrogen-protected distillation vessel assembly is equipped with a condensation device and a reflux control device; the gas and solid discharged from the triple nitrogen-protected distillation vessel assembly are both fed into the waste recovery and treatment device; the waste recovery and treatment device consists of a collection device for collecting waste gas, waste liquid and waste residue, a treatment liquid, a physical stirring device, an ultraviolet generator and an outlet combustion device; the treatment liquid is a turbid liquid in which hydrogen dioxide and titanium dioxide are mixed at a mass ratio of 200:1 to 2 and kept uniformly stirred;

[0007] The process for preparing electronic-grade bis-tert-butylamino-silane includes the following stages:

[0008] S1: Raw Material Preparation

[0009] ① Raw material preparation: Prepare sufficient amounts of methylal and tert-butylamine;

[0010] ②Auxiliary material preparation: Prepare commercially available 1μm microporous filter membrane; sufficient amounts of hexadecyltrimethylammonium bromide, tetraethoxysilane, 10% ethanol aqueous solution, saturated ammonia, a glass plate with an ITO membrane integrated on its surface, sufficient amounts of polymethyl methacrylate, 1% hydrogen chloride ethanol solution, 10% hydrogen chloride aqueous solution, a 100:10 toluene-acetone mixed solution, and a 0.012mm thick mechanically perforated polyester film; wherein the mechanically perforated polyester film has round holes with a diameter of φ0.1mm-φ0.2mm and a pore density of 1 hole / mm². 2 -1.5 pieces / mm 2 ;

[0011] S2: Pure manufacturing of crude bis-tert-butylaminosilane

[0012]

[0013]

[0014] S3: Preparation of nanofiltration membrane and pre-purification

[0015]

[0016]

[0017]

[0018] ​​​​​④After the composite film B is cleaned and naturally dried, it is tightly attached to the mechanically punched polyester film prepared in step ② of S1 to form a new composite film, and then the new composite film is placed in a nitrogen-protected closed space, heated to 125-130℃, and treated for 90-100 min. Then the treated new composite film is completely immersed in the toluene-acetone mixed solution prepared in step ② of S1 for 15-18 h, taken out, cleaned and naturally dried to obtain the composite film C; the composite film C is stacked in 3-5 layers and cut into a size matching the centrifugal double-layer membrane separation device, i.e. the required nanofiltration membrane is obtained;

[0019] ⑤The 1 μm microporous filter film obtained in step ② of stage S1 is arranged at the position close to the axis of the centrifugal double-layer membrane separation device, and the nanofiltration membrane obtained in step ④ is arranged at the position close to the outer wall of the centrifugal double-layer membrane separation device. Then, after the centrifugal double-layer membrane separation device is filled with nitrogen, the treated liquid obtained in step ② of stage S2 is injected along the axis position, and then centrifugal separation is adopted, with the separation parameters being 18,000-25,000 rpm, until physical filtration is completed. The microporous filter film has a foreign matter layer in the middle, the microporous filter film and the nanofiltration membrane have a product layer in the middle, and the reaction liquid layer is outside the nanofiltration membrane; the reaction liquid layer is continuously fed into the feed inlet of the raw material reaction system for recycling; the foreign matter layer is sent to a three-waste recycling treatment device; and the product layer is sent to the next link, which is the pre-purified bis-tert-butylamino-silane;

[0020] ⑥The pre-purified bis-tert-butylamino-silane obtained in step ⑤ is sent to a pre-purified product detection device, and the purity of the bis-tert-butylamino-silane is required to be not less than 99.95%. If the pre-purified bis-tert-butylamino-silane is qualified, it is sent to a three-in-one nitrogen-protected rectifying kettle assembly for rectification;

[0021] S4: Rectification

[0022] ①The qualified pre-purified bis-tert-butylamino-silane obtained in step ④ of stage S3 is fed into a 1st-stage rectifying column in the three-in-one nitrogen-protected rectifying kettle assembly for vacuum distillation, heated by an oil bath partition, and the gas phase escapes to the tray. After multiple condensation and vaporization processes, the rectification product collection valve and the storage tank valve are opened, the bis-tert-butylamino-silane is introduced into the 1st-stage rectification product storage tank, the 1st-stage rectification product storage tank discharge valve and the rectifying column continuous feeding regulating valve are opened, and continuous feeding production is carried out;

[0023] ②The 1st-stage rectification product is fed into a 2nd-stage rectifying column, and step ① is repeated. The bis-tert-butylamino-silane is introduced into the 2nd-stage rectification product storage tank, the 2nd-stage rectification product storage tank discharge valve and the rectifying column continuous feeding regulating valve are opened, and continuous feeding production is carried out;

[0024] ③The 2nd-stage rectification product is placed in a 3rd-stage rectifying column, and step ① is repeated. The bis-tert-butylamino-silane is introduced into the 2nd-stage rectification product storage tank to obtain the required electronic-grade bis-tert-butylamino-silane.

[0025] S5: detection

[0026] ① The electronic grade bis-tert-butyl amino-silane obtained in step ③ of stage S4 is detected, and the purity of the main fraction bis-tert-butyl amino-silane is required to be not less than 99.99%, and if qualified, the trace impurity detection procedure is entered;

[0027] ② The trace impurities in the electronic grade bis-tert-butyl amino-silane in step ③ of stage S4 are detected, and the total content of impurities is required to be not higher than 0.0000005% (8.5N), and if qualified, the packaging procedure is entered.

[0028] Compared with the prior art, the application has the following advantages due to the above technical scheme:

[0029] (1) The application adopts a nanofiltration membrane (pore size 0.001-0.002 μm) independently developed and a commercially available microporous filtration membrane to form a double-membrane structure, and a mild centrifugal method is used to physically filter the solution, which is energy-saving and environmentally friendly, and greatly improves the stability of the product.

[0030] (2) The application carries out targeted recovery or collection and removal treatment of harmful three-waste substances discharged from the production system, and the whole process is controllable and environmentally friendly.

[0031] (3) In addition to the main raw material components, all process auxiliary materials and added components can be completely recycled, which does not increase the extraction cost, so the composition is simple, the cost is low, and it is suitable for industrial production; at the same time, physical filtration is adopted, which is stable and reliable, and the energy consumption is low.

[0032] (4) Compared with conventional technology, the synthesis route is slightly longer, so the production cycle is relatively long, but because different purification technologies are adopted, complementary impurity removal is achieved, so the quality of the final product is more controllable, and the main fraction purity is 99.99%, and the trace impurity content is 8.5N, which can actually reach more than 99.997% of the main fraction purity and 9N of the trace impurity content, and the purity of the electronic grade bis-tert-butyl amino-silane on the market is higher.

[0033] Therefore, the application has the characteristics of environmental protection in the production process, simple types of raw materials, less emissions, and high purity of the product. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 is a structural schematic diagram of the application;

[0035] Figure 2 is a chemical reaction formula of the application;

[0036] In the diagram: 1. Crude distillation vessel assembly; 2. Solid-liquid separation device; 3. Reactant detection device; 4. Centrifugal double-layer membrane separation device; 5. Condensation device; 6. Reflux control device; 7. Triple nitrogen-protected distillation vessel assembly; 8. Nanofiltration membrane; 9. Pre-purified material detection device; 10. Waste recovery and treatment device. Detailed Implementation Example 1

[0037] A kind of appendix Figure 1 The apparatus shown for manufacturing electronic-grade bis-tert-butylamino-silane is based on... Figure 2 The reaction matching setup shown includes a raw material reaction system 1, a centrifugal double-layer membrane separation device 4, a triple nitrogen-protected distillation vessel assembly 7, and a waste recovery and treatment device 10, arranged in sequence from feed to discharge. A solid-liquid separation device 2 and a reactant detection device 3 are installed between the raw material reaction system 1 and the centrifugal double-layer membrane separation device 4. The centrifugal double-layer membrane separation device 4 contains, from the inside out, a commercially available microporous membrane with a pore size of 1 μm and a nanofiltration membrane with a pore size of 0.001 μm-0.002 μm. The intermediate product layer of the centrifugal double-layer membrane separation device 4 is connected to the triple nitrogen-protected distillation vessel assembly 7. The product layer of the centrifugal double-layer membrane separation device 4 and the triple nitrogen-protected distillation vessel assembly are connected. A pre-purified substance detection device 9 is installed between components 7; the centrifugal double-layer membrane separation device 4 is also equipped with a core residue conveying device, which is matched with the waste recovery and treatment device 10; each of the triple nitrogen-protected distillation kettle components 7 is equipped with a condensation device 5 and a reflux control device 6; the gas and solid discharged from the triple nitrogen-protected distillation kettle components 7 are both fed into the waste recovery and treatment device 10; the waste recovery and treatment device 10 consists of a collection device for collecting waste gas, waste liquid and waste residue, a treatment liquid, a physical stirring device, an ultraviolet generating device and an outlet combustion device; wherein the treatment liquid is a turbid liquid in which hydrogen dioxide and titanium dioxide are mixed at a mass ratio of 200:1 to 2 and maintained in a uniform stirring state;

[0038] The process for preparing electronic-grade bis-tert-butylamino-silane includes the following stages:

[0039] S1: Raw Material Preparation

[0040] ① Raw material preparation: Prepare sufficient amounts of methylal and tert-butylamine;

[0041] ②Auxiliary material preparation: prepare commercially available 1 μm microporous filter membrane; sufficient cetyltrimethylammonium bromide, sufficient tetraethoxysilane, sufficient 10% mass fraction of solute in ethanol aqueous solution, sufficient saturated ammonia, glass plate with ITO film on the surface, sufficient polymethyl methacrylate, sufficient 1% mass fraction of solute in hydrogen chloride ethanol solution, sufficient 10% mass fraction of solute in hydrogen chloride aqueous solution, sufficient 100:10 volume ratio of toluene acetone mixed solution, sufficient 0.012 mm thick mechanical punching polyester film; wherein the mechanical punching polyester film has circular holes, a hole diameter of φ0.1 mm-φ0.2 mm, and a hole surface distribution density of 1 / mm 2 -1.5 / mm 2 ;

[0042] S2: Purely manufacturing crude bis-tert-butylamino-silane

[0043] ①Introduce nitrogen into the reaction container of the raw material reaction system 1 to remove air, and then vacuumize to 0.01 MPa-0.05 MPa; according to the molar ratio, 1:2 of the dimethylformamide prepared in step ① of stage S1 is weighed and put into the reaction container, and the reaction is carried out under the protection of nitrogen gas at a pressure of 0.01 MPa-0.05 MPa, the reaction parameters are temperature range of-10℃-0℃, reaction time of 18h-20h, and the process parameters are controlled by distributed control system DCS, and the crude reaction product is obtained; the gas and waste generated in the reaction process are introduced into the three-waste recovery treatment device 10;

[0044] ②The crude reaction product obtained in step ① is injected into the solid-liquid separation device 2 for solid-liquid separation, the solid residue is introduced into the three-waste recovery treatment device 10, and the liquid part is the treated liquid, which is first introduced into the reaction product detection device 3 and then sent to the centrifugal double-layer membrane separation device 4 after passing the test;

[0045] S3: Nanofiltration membrane preparation 8 and pre-purification

[0046] ①In a quartz container, add cetyltrimethylammonium bromide prepared in step ② of stage S1, deionized water and ethanol prepared in step ① of stage S1 according to the mass ratio of 1:(425-430):(140-145) in sequence, stir until the solution is clear, then add saturated ammonia and 6‰-8‰ tetraethoxysilane prepared in step ② of stage S1 into the solution drop by drop according to the mass ratio of 0.08‰-0.1‰ of the mixed solution and 6‰-8‰ of the tetraethoxysilane, stir until completely mixed and uniform, and obtain solution A;

[0047] ②After the glass plate with ITO film integrated on the surface prepared in step ② of stage S1 is cleaned with deionized water and dried, the cleaned glass plate is immersed in the solution A obtained in step ①, and is placed in a nitrogen-protected closed space, and is heated to 62-68℃, and is reacted for 16-18 hours, and then is cleaned with deionized water and dried, and then is placed in a nitrogen-protected closed space, and is heated to 100-105℃, and is treated for 12-16 hours, and then the treated glass plate is completely immersed in the hydrogen chloride ethanol solution prepared in step ② of stage S1, and is stirred for 18-20 minutes, and then is cleaned to obtain the glass plate to be treated;

[0048] ③The surface of the glass plate to be treated obtained in step ② is spin-coated with a layer of polymethyl methacrylate, and then is placed in a nitrogen-protected closed space, and is heated to 115-120℃, and is kept for 10-12 minutes, and then is cooled to room temperature, and then is completely immersed in the hydrogen chloride aqueous solution prepared in step ② of stage S1, and is placed for 2-3 days, and then the film layer on the glass plate is peeled off to obtain a composite film B;

[0049] ④After the composite film B is cleaned and naturally dried, the composite film B is tightly attached to the mechanically punched polyester film prepared in step ② of stage S1 to form a new composite film, and then the new composite film is placed in a nitrogen-protected closed space, and is heated to 125-130℃, and is treated for 90-100 minutes, and then the treated new composite film is completely immersed in the toluene acetone mixed solution prepared in step ② of stage S1, and is treated for 15-18 hours, and then is taken out, cleaned and naturally dried to obtain a composite film C; the composite film C is stacked in 3-5 layers and is cut into a size matching the centrifugal double-layer membrane separation device 4 to obtain the required nanofiltration membrane 8;

[0050] ⑤The 1 μm microporous filter film obtained in step ② of stage S1 is arranged at a position close to the axis of the centrifugal double-layer membrane separation device 4, and the nanofiltration membrane 8 obtained in step ④ is arranged at a position close to the outer wall of the centrifugal double-layer membrane separation device 4, and then nitrogen is filled in the centrifugal double-layer membrane separation device 4, and then the liquid to be treated obtained in step ② of stage S2 is injected along the axis, and then is centrifuged at a speed of 18,000-25,000 rpm until physical filtration is completed, and then the microporous filter film has a foreign matter layer in the middle, the microporous filter film and the nanofiltration membrane 8 have a product layer in the middle, and the nanofiltration membrane 8 has a reaction liquid layer outside; the reaction liquid layer is continuously fed into the feed inlet of the raw material reaction system 1 for recycling; the foreign matter layer is sent to the three-waste recycling treatment device 10; and the product layer is sent to the next link, and the product layer is the pre-purified bis-tert-butylamino-silane;

[0051] ⑥ The pre-purified bis-tert-butylamino-silane obtained in step ⑤ is sent to the pre-purified material detection device 9. The purity of bis-tert-butylamino-silane is required to be no less than 99.95%. Then the qualified pre-purified bis-tert-butylamino-silane is sent to the triple nitrogen-protected distillation vessel assembly 7 for distillation.

[0052] S4: Distillation

[0053] ① The qualified pre-purified bis-tert-butylamino-silane obtained in step ④ of stage S3 is fed into the first-stage distillation column of the triple nitrogen-protected distillation vessel assembly 7 for vacuum distillation. It is heated by the oil bath wall and the gas phase escapes to the tower plate. After multiple condensation and vaporization processes, the distillate collection valve and storage tank valve are opened to introduce bis-tert-butylamino-silane into the first-stage distillate storage tank. The first-stage distillate storage tank discharge valve and the distillation column continuous feed regulating valve are opened for continuous feeding production.

[0054] ② Feed the first-stage distillate into the second-stage distillation column, repeat step ①, introduce bis-tert-butylamino-silane into the second-stage distillate storage tank, open the discharge valve of the second-stage distillate storage tank and the continuous feed regulating valve of the distillation column, and continue feeding for production.

[0055] ③ Place the second-stage distillate into the third-stage distillation column, repeat step ①, and introduce bis-tert-butylamino-silane into the second-stage distillate storage tank to obtain the desired electronic-grade bis-tert-butylamino-silane;

[0056] S5: Detection

[0057] ① The electronic-grade bis-tert-butylamino-silane obtained in step ③ of stage S4 is tested. The purity of the main fraction of bis-tert-butylamino-silane is required to be not less than 99.99%. If it is qualified, it will proceed to the trace impurity detection procedure.

[0058] ②Detect trace impurities in electronic grade bis-tert-butylamino-silane in step S4 of stage ③. The total impurity content should not exceed 0.0000005% (8.5N). If it passes the test, proceed to the packaging process.

[0059] The electronic-grade bis-tert-butylamino-silane (BTBAS) manufactured according to the method of this embodiment has a purity of not less than 99.99% for its main component bis-tert-butylamino-silane and a total impurity content of not more than 0.0000005%.

[0060] The foregoing description of the disclosed embodiments is merely exemplary in nature and is not intended to limit the present application, application, or the application to the specific embodiments. Numerous modifications and variations are possible in light of the above teachings. It is therefore to be understood that within the scope of the claims and their equivalents, the application can be practiced otherwise than as specifically described.

Claims

1. A process for the production of electronic grade bis-tert-butylamino-silane, characterized by: The manufacturing method is matched with a manufacturing device which is provided with a raw material reaction system (1), a centrifugal double-layer membrane separation device (4), a triple nitrogen protection rectification kettle assembly (7), and a three-waste recycling device (10) in sequence from feeding to discharging; wherein the solid-liquid separation device (2) and the reactant detection device (3) are arranged between the raw material reaction system (1) and the centrifugal double-layer membrane separation device (4); the commercially available microporous filter membrane with a filter pore size of 1 μm and the nanofiltration membrane (8) with a pore size of 0.001 μm-0.002 μm are sequentially arranged in the centrifugal double-layer membrane separation device (4) from inside to outside; the intermediate product layer in the centrifugal double-layer membrane separation device (4) is communicated with the triple nitrogen protection rectification kettle assembly (7), and the pre-purified product detection device (9) is arranged between the intermediate product layer of the centrifugal double-layer membrane separation device (4) and the triple nitrogen protection rectification kettle assembly (7); the centrifugal double-layer membrane separation device (4) is further provided with a core residue conveying device which is matched with the three-waste recycling device (10); the triple nitrogen protection rectification kettle assembly (7) is provided with the condensing device (5) and the reflux control device (6); the gas and solid discharged from the triple nitrogen protection rectification kettle assembly (7) are introduced into the three-waste recycling device (10); the three-waste recycling device (10) is composed of a collection device for collecting waste gas, waste liquid and waste residue, a treatment liquid, a physical stirring device, an ultraviolet light generating device and an outlet combustion device; wherein the treatment liquid is the turbid liquid prepared by mixing hydrogen dioxide and titanium dioxide at a mass ratio of 200:1-2 and uniformly stirring; Process for the preparation of electronic grade bis-tert-butylamino-silane comprising the following stages: S1: raw material preparation 1. Raw material preparation: prepare sufficient amount of methylal and tert-butylamine; ②Auxiliary material preparation: prepare commercially available 1 μm microporous filter membrane; sufficient cetyltrimethylammonium bromide, sufficient tetraethoxysilane, sufficient 10% solute mass fraction ethanol aqueous solution, sufficient saturated ammonia water, glass plate with ITO film integrated on the surface, sufficient polymethyl methacrylate, sufficient 1% solute mass fraction hydrogen chloride ethanol solution, sufficient 10% solute mass fraction hydrogen chloride aqueous solution, sufficient 100:10 volume ratio toluene acetone mixed solution, sufficient 0.012 mm thickness mechanical punching polyester film; wherein the mechanical punching polyester film has circular holes, a hole diameter of 0.1-0.2 mm, and a hole surface distribution density of 1 / mm 2 -1.5 / mm 2 ; S2: pure preparation of crude bis(tert-butylamino)silane 1. Introduce nitrogen into the reaction vessel of the raw material reaction system (1) to remove air, and then vacuumize to 0.01-0.05 MPa; introduce the methylal and tert-butylamine prepared in step 1 of stage S1 at a molar ratio of 1:2 into the reaction vessel, and control the reaction system to react under nitrogen protection at a gas pressure of 0.01-0.05 MPa; the reaction parameters are a temperature range of -10-0°C, and the reaction time is 18-20 h; the process parameters are controlled by a distributed control system (DCS); the crude reaction product is obtained; the gas and waste generated during the reaction are introduced into the three-waste recycling device (10); 2. Introduce the crude reaction product obtained in step 1 into the solid-liquid separation device (2) for solid-liquid separation; the solid residue is introduced into the three-waste recycling device (10), and the liquid part is the treated liquid; the treated liquid is first introduced into the reactant detection device (3), and then introduced into the centrifugal double-layer membrane separation device (4) after passing the detection; S3: nanofiltration membrane preparation (8) and pre-purification ①In a quartz container, add the cetyltrimethylammonium bromide prepared in step ② of stage S1, deionized water and the ethanol prepared in step ① of stage S1 in the order of 1: (425-430): (140-145) by mass ratio, stir until the solution is clear, then add dropwise into the solution the saturated ammonia water prepared in step ② of stage S1 accounting for 0.08‰-0.1‰ of the mass of the mixed solution by mass ratio and 6‰-8‰ of tetraethoxysilane, stir until completely mixed and uniform, and obtain solution A; ②After the glass plate with ITO film integrated on the surface prepared in step ② of stage S1 is cleaned with deionized water and dried, the cleaned glass is immersed in the solution A obtained in step ①, placed in a nitrogen-protected closed space, heated to 62℃-68℃, and reacted for 16h-18h, then cleaned with deionized water and dried, and then placed in a nitrogen-protected closed space, heated to 100℃-105℃, and treated for 12h-16h, then the treated glass plate is completely immersed in the hydrogen chloride ethanol solution prepared in step ② of stage S1, stirred for 18min-20min, cleaned, and the treated glass plate is obtained; ③The surface of the treated glass plate obtained in step ② with the original ITO film integrated is spin-coated with a layer of polymethyl methacrylate, then left to stand for 80min-100min, the spin-coated glass plate is placed in a nitrogen-protected closed space, heated to 115℃-120℃, and kept for 10min-12min, then left to stand to room temperature, then completely immersed in the hydrogen chloride aqueous solution prepared in step ② of stage S1, and left to stand for 2-3 days, the film layer on the glass plate falls off, and composite film B is obtained; ④After the composite film B is cleaned and naturally dried, it is tightly attached to the mechanically punched polyester film prepared in step ② of stage S1 to form a new composite film, then the new composite film is placed in a nitrogen-protected closed space, heated to 125℃-130℃, and treated for 90min-100min, then the treated new composite film is completely immersed in the toluene acetone mixed solution prepared in step ② of stage S1, treated for 15h-18h, taken out, cleaned, and naturally dried, and the composite film C is obtained; the composite film C is stacked in 3-5 layers and cut into a size matching the centrifugal double-layer membrane separation device (4), and the required nanofiltration membrane (8) is obtained. ⑤ Place the 1μm microporous filter membrane obtained in step ② of stage S1 near the axis of the centrifugal double-layer membrane separation device (4), and place the nanofiltration membrane (8) obtained in step ④ near the outer wall of the centrifugal double-layer membrane separation device (4). After filling the centrifugal double-layer membrane separation device (4) with nitrogen for protection, inject the liquid to be treated obtained in step ② of stage S2 along the axis. Then, centrifuge separation is performed with separation parameters of 18000rpm-25000rpm until physical filtration is completed. The middle of the microporous filter membrane is a layer of impurities, the middle of the microporous filter membrane and the nanofiltration membrane (8) is a layer of yield, and the outside of the nanofiltration membrane (8) is a layer of reaction liquid. The layer of reaction liquid is fed into the feed inlet of the raw material reaction system (1) for recycling. The impurity layer is sent to the waste recycling treatment device (10). The layer of yield is sent to the next stage. The layer of yield is the pre-purified bis(tert-butylamino)silane. ⑥ The pre-purified bis(tert-butylamino)silane obtained in step ⑤ is sent to the pre-purified material detection device (9). The purity of bis(tert-butylamino)silane is required to be no less than 99.95%. Then the qualified pre-purified bis(tert-butylamino)silane is sent to the triple nitrogen-protected distillation vessel assembly (7) for distillation. S4: Distillation ① The qualified pre-purified bis(tert-butylamino)silane obtained in step ④ of stage S3 is fed into the first-stage distillation column of the triple nitrogen-protected distillation vessel assembly (7) for vacuum distillation. It is heated by the oil bath wall and the gas phase escapes to the tower plate. After multiple condensation and vaporization processes, the distillate collection valve and storage tank valve are opened to introduce bis(tert-butylamino)silane into the first-stage distillate storage tank. The first-stage distillate storage tank discharge valve and the distillation column continuous feed regulating valve are opened for continuous feeding production. ② Feed the first-stage distillate into the second-stage distillation column, repeat step ①, introduce bis(tert-butylamino)silane into the second-stage distillate storage tank, open the discharge valve of the second-stage distillate storage tank and the continuous feed regulating valve of the distillation column, and continue feeding for production. ③ Place the second-stage distillate into the third-stage distillation column, repeat step ①, and introduce bis(tert-butylamino)silane into the second-stage distillate storage tank to obtain the desired electronic-grade bis-tert-butylamino-silane; S5: Detection ① The electronic-grade bis-tert-butylamino-silane obtained in step ③ of stage S4 is tested. The purity of the main fraction of bis(tert-butylamino)silane is required to be not less than 99.99%. If it is qualified, it will proceed to the trace impurity detection procedure. ②Detect trace impurities in electronic grade bis-tert-butylamino-silane in step S4 of stage ③. The total impurity content should not exceed 0.0000005% (8.5N). If it passes the test, proceed to the packaging process.

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