Device for monitoring the content of ammonia, water and / or hydrolysis products in the distillation of ethylsilane

Abstract

The utility model provides a device for monitoring ammonia gas, water and / or hydrolysis product content in the process of ethylsilane rectification, adopts the device of the utility model can realize ammonia gas, water and / or hydrolysis product content monitoring in the process of ethylsilane rectification. The device includes sample gas delivery pipeline and positive pressure flow measuring chamber, further includes the tail gas treatment device, gas recovery device for setting in positive pressure flow measuring chamber, is used for supplying the calibration gas supply device of required calibration gas, gas replacement device, three -way valve I, three -way valve II and is equipped with gas pool's fourier transform infrared spectrometer, positive pressure flow measuring chamber is equipped with inert gas supply unit for making dry inert gas in positive pressure flow measuring chamber and makes positive pressure flow measuring chamber reach the preset positive pressure value, is equipped with the moisture content determination appearance for detecting moisture content in positive pressure flow measuring chamber.

Description

Technical Field

[0001] This utility model relates to monitoring technology for the distillation process of silane, specifically to a device for monitoring the content of ammonia, water and / or hydrolysis products during the distillation process of silane. Background Technology

[0002] Silane is an important raw material in the vapor deposition process of silicon oxide films, silicon nitride films, and polycrystalline silicon films in the semiconductor industry. It has advantages such as fast deposition rate, low deposition temperature, and high uniformity of deposited films.

[0003] The magnesium silicide process (Komatsu process) is a mature technology for synthesizing silane. This process uses liquid ammonia as the reaction medium. Due to their respective physicochemical properties, separating liquid ammonia and the product silane presents certain challenges. Therefore, the ammonia content during silane distillation is a crucial quality control indicator. In addition, the presence of trace amounts of water can lead to the hydrolysis of silane, generating silane ethers or other polymers containing Si-O-Si structures. Therefore, controlling moisture content and monitoring hydrolysis products are equally important for the yield and purity of silane.

[0004] In summary, monitoring and control of ammonia, water, and hydrolysis products during the distillation of silane are crucial, especially the simultaneous online monitoring of these three impurities. Currently, the specialty gas analysis industry commonly uses gas chromatography for process monitoring and control; however, the strong adsorption properties of ammonia and the strong polarity of water prevent accurate quantification using gas chromatography. Furthermore, in existing technologies for preparing silane via the magnesium silicide method, methods and equipment for monitoring the silane distillation process are lacking, hindering efficient production. Utility Model Content

[0005] To address at least one deficiency in the existing technology, this utility model provides a device for monitoring the content of ammonia, water and / or hydrolysis products during the distillation of silane. Using the device of this utility model, the content of ammonia, water and / or hydrolysis products during the distillation of silane can be monitored.

[0006] To achieve its purpose, this utility model provides the following technical solution: This utility model provides a device for monitoring the content of ammonia, water and / or hydrolysis products during the distillation of silane. The device includes a sample gas delivery pipeline and a positive pressure flow measurement chamber. It also includes a tail gas treatment device, a gas recovery device, a calibration gas supply device for supplying the required calibration gas, a gas replacement device, a three-way valve I, a three-way valve II, and a Fourier transform infrared spectrometer equipped with a gas cell. The positive pressure flow measurement chamber is equipped with an inert gas supply unit to continuously circulate dry inert gas within the chamber and maintain a preset positive pressure value. The positive pressure flow measurement chamber also contains a moisture content analyzer for detecting moisture content. One end of the sample gas delivery pipeline is connected to the sample gas outlet of the distillation apparatus, and the other end extends into the positive pressure flow measurement chamber and is connected to port a of the three-way valve I. The sample gas delivery pipeline is equipped with a diaphragm valve I. The inlet of the gas pool is connected to port b of the three-way valve I via a first pipeline; the calibration gas supply device is connected to port c of the three-way valve I via a second pipeline. The gas replacement device is connected to the first pipeline via a third pipeline. The gas replacement device is used to evacuate the pipeline and device connected to it and to replace them with inert gas. The exhaust gas outlet of the gas pool is connected to port b of the three-way valve II via a fourth pipeline. The exhaust gas treatment device is connected to port a of the three-way valve II, and port c of the three-way valve II is connected to the gas recovery device. The first pipeline, the third pipeline, and the fourth pipeline are respectively equipped with diaphragm valve III, diaphragm valve II, and diaphragm valve IV.

[0007] Preferably, the section of the sample gas delivery pipeline located between port a of the diaphragm valve I and the three-way valve I is connected to the gas recovery device via a fifth pipeline.

[0008] Preferably, a needle valve II is provided on the fifth pipeline.

[0009] Preferably, a pressure reducing valve I is provided on the sample gas delivery pipeline; The fourth pipeline is also equipped with a needle valve I.

[0010] Preferably, at least the section of the sample gas delivery pipeline near the sample gas outlet of the distillation apparatus is a heat tracing cable with heating and temperature control functions; the second pipeline is a heat tracing cable with heating and temperature control functions.

[0011] Preferably, the positive pressure flow measurement chamber is equipped with a heater and a pressure sensor I.

[0012] Preferably, the moisture content analyzer is a dew point meter.

[0013] Preferably, the inert gas supply unit includes an inert gas source, a drying column for drying and removing moisture from the inert gas output from the inert gas source, an inert gas delivery pipeline, and an inert gas output pipeline; The inert gas source is connected to the inlet of the positive pressure flow measuring chamber through the inert gas delivery pipeline; the drying column is provided on the inert gas delivery pipeline; the pressure reducing valve II is also provided on the inert gas delivery pipeline; The inert gas output pipeline is connected to the outlet of the positive pressure flow measurement chamber, and a needle valve III is provided on the inert gas output pipeline.

[0014] Preferably, the gas pool is equipped with a pressure sensor II; And / or, the gas pool has heating and temperature control functions; And / or, the optical path length of the gas cell is 5-30m; And / or, the Fourier transform infrared spectrometer is also equipped with a vacuum optical stage and an MCT detector.

[0015] The technical solution provided by this utility model has the following beneficial effects: The device based on this invention can be used to detect sample gases during the distillation of silane, which helps to efficiently and accurately monitor the content of ammonia, water, and hydrolysis products, and helps to promote process optimization, ensure production safety, and achieve "process controllability" and "batch stability". Attached Figure Description

[0016] Figure 1 This is a schematic diagram of an apparatus for monitoring the content of ammonia, water, and / or hydrolysis products during the distillation of silane in one embodiment.

[0017] Explanation of reference numerals in the attached diagram: 1. Inert gas source; 2. Drying column; 3. Distillation apparatus; 4. Positive pressure flow measurement chamber; 5. Heater; 6. Fourier transform infrared spectrometer; 7. Gas cell; 8. Moisture content analyzer; 9. Pressure sensor I; 10. Calibration gas supply device; 11. Tail gas treatment device; 12. Gas recovery device; 13. Gas replacement device; 14. Sample gas delivery pipeline; 15. Pressure reducing valve I; 16. Diaphragm valve I. 7. Three-way valve I; 18. Diaphragm valve III; 19. Diaphragm valve IV; 20. Needle valve I; 21. Three-way valve II; 22. Pressure sensor II; 23. Fifth pipeline; 24. Needle valve II; 25. Needle valve III; 26. Pressure reducing valve II; 27. Inert gas delivery pipeline; 28. Second pipeline; 29. ​​First pipeline; 30. Third pipeline; 31. Diaphragm valve II; 32. Fourth pipeline; 33. Inert gas output pipeline. Detailed Implementation

[0018] To facilitate understanding of this utility model, the following description will further illustrate it with reference to embodiments. It should be understood that the following embodiments are merely for better understanding of this utility model and do not imply that this utility model is limited to the following embodiments.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The term "and / or" as used herein may include any and all combinations of one or more of the associated listed items. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0020] This invention provides a device for monitoring the content of ammonia, water, and / or hydrolysis products during the distillation of silane. See [link to device]. Figure 1 The device includes a sample gas delivery pipeline 14 and a positive pressure flow measurement chamber 4, and also includes an exhaust gas treatment device 11, a gas recovery device 12, a calibration gas supply device 10, a gas replacement device 13, a three-way valve I 17, a three-way valve II 21, and a Fourier transform infrared spectrometer 6 equipped with a gas cell 7, all disposed within the positive pressure flow measurement chamber 4; wherein, the calibration gas supply device 10 is used to supply the required calibration gas, and can be a calibration gas supply device commonly used in the art, such as having a calibration gas inlet for outputting the required calibration gas, and an outlet valve provided on the calibration gas inlet.

[0021] The positive pressure flow measurement chamber 4 is equipped with an inert gas supply unit, which is used to continuously circulate dry inert gas in the positive pressure flow measurement chamber 4 and to make the positive pressure flow measurement chamber 4 reach a preset positive pressure value (e.g., pressure of 0.01-0.5 bar). The positive pressure flow measurement chamber 4 is equipped with a moisture content meter 8 for detecting moisture content. The moisture content meter 8 is, for example, a dew point meter, which monitors the water content in the dry inert gas in the positive pressure flow measurement chamber 4 in real time. One end of the sample gas delivery line 14 is connected to the sample gas outlet of the distillation apparatus 3, and the other end extends into the positive pressure flow measurement chamber 4 and is connected to port a of the three-way valve I 17. The sample gas delivery line 14 is equipped with a diaphragm valve I 16 and a pressure reducing valve I 15. The inlet of the gas tank 7 is connected to port b of the three-way valve I 17 via the first pipeline 29; the calibration gas supply device 10 is connected to port c of the three-way valve I 17 via the second pipeline 28. The gas replacement device 13 is connected to the first pipeline 29 via the third pipeline 30. The gas replacement device 13 is used to evacuate the connected pipelines and devices and to replace them with inert gas. Specifically, the gas replacement device 13 can be a conventional device in the art that has the functions of evacuation and inert gas replacement of connected pipelines and devices. For example, it may include a vacuum pump group connected in series with the pipeline 30 and an ultra-high purity inert gas source. By operating the gas replacement device 13, the gas and water in the connected pipelines can be completely replaced. In a specific example, the gas replacement device 13 can be controlled by a PLC. In this invention, the clever arrangement of the gas replacement device 13 helps to ensure the freshness of the sample and the real-time nature of the test results.

[0022] The exhaust gas outlet of the gas pool 7 is connected to port b of the three-way valve II 21 via the fourth pipeline 32, the exhaust gas treatment device 11 is connected to port a of the three-way valve II 21, and port c of the three-way valve II 21 is connected to the gas recovery device 12. Diaphragm valve III 18, diaphragm valve II 31, and diaphragm valve IV 19 are respectively installed on the first pipeline 29, the third pipeline 30, and the fourth pipeline 32.

[0023] Preferably, the section of the sample gas delivery line 14 located between port a of diaphragm valve I 16 and three-way valve I 17 is connected to the gas recovery device 12 via a fifth line 23. Specifically, the fifth line 23 is equipped with a needle valve II 24. During continuous real-time monitoring, the needle valve II 24 is opened, allowing the sample gas output from the distillation unit 3 to flow out in two streams: one stream flows to the gas pool 7, and the other flows to the gas recovery device 12, forming a loop purging. Compared to keeping only one stream flowing to the gas pool 7, this allows for a larger and smoother gas output during continuous real-time monitoring, enabling the Fourier transform infrared spectrometer 6 to detect the freshest gas sample and ensuring the real-time nature of the detection results.

[0024] Preferably, at least the section 34 of the sample gas delivery line 14 near the sample gas outlet of the distillation apparatus 3 is a heat tracing cable with heating and temperature control functions. The second line 28 is also a heat tracing cable with heating and temperature control functions. Existing heat tracing cables with heating and temperature control functions in the art can be used. This preferred design helps prevent moisture condensation on the pipe wall, thereby ensuring the accuracy of the test results. In some examples, an integrated electric heat tracing cable is used, for example, made of 316L stainless steel, internally polished, with a temperature controller and a temperature control range of 35~80°C.

[0025] Preferably, the positive pressure flow measurement chamber 4 is equipped with a heater 5 and a pressure sensor I 9. The heater 5 heats the chamber, for example, maintaining the ambient temperature between 35 and 80°C, preventing moisture condensation on the chamber walls and improving the accuracy of the detection results.

[0026] Specifically, the fourth pipeline 32 is also equipped with a needle valve I 20, which helps to regulate the pressure in the gas pool 7. Specifically, the gas pool 7 is equipped with a pressure sensor II 22.

[0027] In this invention, all relevant devices and components for gas sample detection (such as exhaust gas treatment device 11, gas recovery device 12, calibration gas supply device 10, gas replacement device 13, three-way valve I 17, three-way valve II 21, and Fourier transform infrared spectrometer 6 equipped with gas cell 7) are placed inside the positive pressure flow measurement chamber 4. The periphery of the positive pressure flow measurement chamber 4 is sealed. The positive pressure flow measurement chamber 4 is equipped with an inert gas supply unit, which ensures a continuous flow of dry inert gas in the space inside the positive pressure flow measurement chamber 4 and maintains positive pressure. This effectively prevents moisture in the air in the detection environment from seeping into the pipelines, devices, and components related to the detection process, thus ensuring the accuracy of the detection results. Preferably, the inert gas supply unit includes an inert gas source 1, a drying column 2 for drying and removing moisture from the inert gas output from the inert gas source, an inert gas delivery pipeline 27, and an inert gas output pipeline 33. The inert gas source 1 is connected to the inlet of the positive pressure flow measurement chamber 4 via the inert gas delivery pipeline 27. The drying column 2 is installed on the inert gas delivery pipeline 27. A pressure reducing valve II 26 is also installed on the inert gas delivery pipeline 27. The inert gas output pipeline 33 is connected to the outlet of the positive pressure flow measurement chamber 4, and a needle valve III 25 is installed on the inert gas output pipeline 33. The drying column 2 can be a commonly used drying column in the art capable of adsorbing and drying moisture in the inert gas; there are no particular limitations on this. Preferably, the moisture content in the inert gas entering the positive pressure flow measurement chamber 4 is below 10 ppb through the drying column 2. By adjusting pressure reducing valve II 26 and needle valve III 25, the intake and exhaust volume of dry inert gas in the positive pressure flow measurement chamber 4 are controlled, so that the chamber contains dry inert gas flowing at a certain pressure, which helps to ensure that the test results are not affected by moisture in the environment.

[0028] In this invention, the Fourier transform infrared spectrometer 6 can be a commonly used instrument in the field, and it can have a conventional configuration. In addition to being equipped with a gas cell 7, it may also be equipped with a vacuum optical stage to eliminate the absorption of moisture in the atmosphere and ensure the accuracy of the detection results; and it may also be equipped with a liquid nitrogen-cooled high-sensitivity MCT detector to ensure the low detection limit of the instrument. The gas cell 7 is selected to have heating and temperature control functions, and the optical path length is preferably 5-30m. The gas cell 7 is mechanically connected to the Fourier transform infrared spectrometer, and the gas cell is preferably of the type with high temperature resistance and anti-adsorption design.

[0029] The exhaust gas treatment device 11 is used to treat gases that do not need to be recovered, such as those that are discharged externally.

[0030] The gas recovery device 12 is used to recover silane gas and loop purging gas, for example, to store and recover these gases.

[0031] The calibration gas supply device 10 is mainly used to provide various calibration gases required in the calibration process. For example, for water detection, the calibration gas includes calibration gases with different water concentrations, which can be obtained by mixing different amounts of water into an inert gas. For ammonia detection, the calibration gas includes calibration gases with different ammonia concentrations. For hydrolysis product detection, the calibration gas includes calibration gases with different concentrations of hydrolysis products. Different concentrations of calibration gas can be obtained by mixing different amounts of the target substance into an inert gas.

[0032] The "inert gas" mentioned in the text can be nitrogen, helium, argon, etc.

[0033] For ease of understanding, the following is an exemplary description of the working process of using the device provided by this utility model for monitoring the content of ammonia, water and / or hydrolysis products during the distillation of silane: 1. Turn on the heater 5 of the positive pressure flow measurement chamber 4 to control the temperature of the positive pressure flow measurement chamber 4 at 50-80℃. Open the outlet of the inert gas source 1 and adjust the pressure reducing valve II 26 to keep the pressure between 0.01-1 bar. The inert gas enters the positive pressure flow measurement chamber 4 after passing through the drying column 2. Adjust the needle valve III 25 to keep the pressure in the positive pressure flow measurement chamber 4 between 0.01-0.5 bar. Observe the dew point meter reading to be below 10 ppb.

[0034] 2. System replacement: 2.1 Open diaphragm valve II 31 and diaphragm valve III 18, keep port a and port b connected by three-way valve I17, start gas replacement device 13, turn on temperature control of gas pool 7 (40-60℃), gas replacement device 13 performs "vacuuming-introduction of dry inert gas" cycle replacement of sample gas delivery pipeline 14 and gas pool 7 3-5 times, the above cycle replacement process can be controlled by PLC.

[0035] 2.2 Afterwards, the three-way valve I 17 keeps ports b and c connected, diaphragm valves II 31 and III 18 remain open, and the gas replacement device 13 starts to start, performing a "vacuuming-introduction of dry inert gas" cycle replacement of the calibration gas in the calibration gas supply device 10 through the pipeline 3-5 times. The above cycle replacement process can be controlled by PLC. Afterwards, all valves are reset, and the three-way valves I 17 and II 21 are closed.

[0036] 3. Calibration: Open diaphragm valve III 18, diaphragm valve IV 19, and needle valve I 20. Connect ports b and c of three-way valve I 17. Introduce the corresponding calibration gas into the second pipeline 28 through calibration gas supply device 10. This serves as the temperature control for the heating cable of the second pipeline 28, with a temperature control range of 35~80℃ and an output pressure set between 0.01-1 bar. Keep ports b and a of three-way valve II 21 connected. The calibration gas output from calibration gas supply device 10 flows through gas pool 7 and enters tail gas treatment device 11. After 3-10 minutes, close diaphragm valve III 18, diaphragm valve IV 19, and needle valve I 20. Record the reading of pressure sensor II 22. Start detection using Fourier transform infrared spectrometer 6 (FT-IR). After the test is completed, all valves are reset (three-way valve I 17 and three-way valve II 21 are closed), diaphragm valve III 18 is opened, gas replacement device 13 is started, and "vacuuming-introduction of dry inert gas" is cyclically replaced 2-3 times. After that, gas replacement device 13 is closed and diaphragm valve III 18 is closed.

[0037] 4. Initial monitoring of distillation sample: Turn on the temperature control function of section 34 of the sample gas delivery line 14 (which is a heated cable), and set the temperature control to 35-80℃; open pressure reducing valve I 15, with an output pressure range of 0.01-1 bar; keep ports a and b connected with three-way valve I 17; open diaphragm valves I 16, III 18, IV 19, and needle valve I 20; keep ports b and c connected with three-way valve II 21. The sample gas output from distillation device 3 enters gas recovery device 12 through gas cell 7. After 3-10 minutes, adjust needle valve I 20 and record the reading of pressure sensor II 22 to match the reading in step 3. Reset all valves and start FT-IR detection.

[0038] 5. Continuous monitoring method 1 during distillation: Open the sampling valve of distillation unit 3, activate the temperature control function of section 34 (heated cable) in sample gas delivery pipeline 14, maintaining the temperature between 35-80℃, open pressure reducing valve I 15, keeping the output pressure of pressure reducing valve I 15 between 0.01-1 bar, keep ports a and b of three-way valve I 17 connected, keep diaphragm valves I 16, III 18, and IV 19 open, adjust the opening of needle valve I 20 to make the reading of pressure sensor II 22 consistent with step 3, keep needle valve II 24 at a certain opening, and keep ports b and c of three-way valve II 21 connected. In this state, gas in gas cell 7 can be sampled and analyzed in real time, with a frequency of >60 times / h.

[0039] 6. Continuous monitoring method 2 during distillation: Perform 6-1 before sample testing and 6-2 when preparing for monitoring. For each new time point sample test, first perform 6-1, then perform 6-2.

[0040] 6-1: Open diaphragm valve II 31 and three-way valve I 17 to keep ports a and b connected, open diaphragm valve III 18, start gas replacement device 13, evacuate for at least 1 minute, and then reset all valves. In particular, to ensure that the optical path system in gas cell 7 is not damaged, the cavity of gas cell 7 is under slight negative pressure.

[0041] 6-2: Open pressure reducing valve I 15, output pressure range 0.01-1 bar, temperature control of the section of sample gas delivery line 14 with heat tracing cable is 35-80℃; keep ports a and b connected with three-way valve I 17, open diaphragm valve I 16, diaphragm valve III 18, diaphragm valve IV 19, and needle valve I 20, keep ports b and c connected with three-way valve II 21, sample gas output from distillation unit 3 enters gas recovery device through gas cell 7, adjust needle valve I 20 after 3-10 minutes, record the reading of pressure sensor II 22 to match the reading in step 3, reset all valves, and start FT-IR detection.

[0042] 7. Instrument Detection Data Processing: When detecting ammonia, water, and hydrolysis products containing Si-O-Si structures in the gas sample of silane after distillation using a distillation apparatus, the selection of infrared wavelengths must be based on the infrared absorption peaks of the characteristic functional groups of each substance, while avoiding absorption interference between silane itself and various impurities. Through theoretical research and repeated experiments, the inventors of this utility model selected the core wavelength combination: NH3 (931 cm⁻¹). -1 ) + H2O (1640 cm -1 ) + Si-O-Si (1080 cm) -1By using peak area quantification, infrared monitoring of ammonia, water, and Si-O-Si can be accurately and efficiently completed during the distillation of silane.

[0043] This invention primarily develops a detection device system based on Fourier transform infrared (FTIR) detection technology, specifically suitable for detecting the content of ammonia, water, and hydrolysis products in sample gas during the distillation of silane. This detection system integrates a positive pressure flow measurement chamber, a calibration gas supply device, a gas replacement device, a tail gas treatment device, and a gas recovery device into a Fourier transform infrared (FTIR) detector. These devices are organically combined through pipelines and valves to form a complete system. Detection of sample gas during the silane distillation process using this system facilitates efficient and accurate monitoring of the content of ammonia, water, and hydrolysis products. Specific devices and components not specifically described herein are those understood or known by those skilled in the art based on conventional technical means, common knowledge, and existing technology, and will not be elaborated upon individually.

[0044] The present invention will be further illustrated by a specific embodiment below, but it should not be construed as being limited to this.

[0045] Where specific experimental steps or conditions are not specified in the examples, the corresponding conventional experimental steps or conditions in this technical field can be followed. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0046] Example 1 In this embodiment, the inert gas used is nitrogen.

[0047] 1. Turn on the heater 5 of the positive pressure flow measurement chamber 4 to control the temperature of the positive pressure flow measurement chamber 4 at 60℃. Open the outlet of the inert gas source 1 and adjust the pressure reducing valve II 26 to a pressure of 0.5 bar. Nitrogen enters the positive pressure flow measurement chamber 4 after passing through the drying column 2. Adjust the needle valve III 25 to a half-turn opening to maintain the pressure in the positive pressure flow measurement chamber 4 at 0.1 bar. The dew point meter reading is 8 ppb.

[0048] 2. System replacement: 2.1. The temperature control of gas cell 7 is turned on and the temperature is controlled at 60℃. Diaphragm valve II 31 and diaphragm valve III 18 are opened. Three-way valve I 17 keeps ports a and b connected. Gas replacement device 13 starts and performs "vacuuming-introduction of dry inert gas" cycle replacement 3 times through PLC control of sample gas delivery pipeline 14 and gas cell 7.

[0049] 2.2 Afterwards, keep ports b and c connected in the three-way valve I 17, keep diaphragm valve II 31 and diaphragm valve III 18 open, start the gas replacement device 13, and perform a "vacuuming-introduction of dry inert gas" cycle to replace the calibration gas in the calibration gas supply device 10 through the pipeline 3 times; after that, all valves are reset, and the three-way valve I 17 and the three-way valve II 21 are both closed.

[0050] 3. Calibration: Open diaphragm valve III 18, diaphragm valve IV 19, and needle valve I 20. Keep ports b and c connected with three-way valve I 17. Introduce calibration gas containing water of the required concentration into the second pipeline 28 through calibration gas supply device 10. This serves as the temperature control for the heat tracing cable of the second pipeline 28, with a temperature control range of 60℃ and an output pressure set at 0.1 bar. Keep ports b and a connected with three-way valve II 21. The calibration gas output from calibration gas supply device 10 flows through gas pool 7 into tail gas treatment device 11. After 5 minutes, close diaphragm valve III 18, diaphragm valve IV 19, and needle valve I 20. Pressure sensor II reads 0.075 bar, and FT-IR detection begins.

[0051] Repeat steps 2.2 and 3, introducing calibration gases containing different concentrations of water for FT-IR detection to obtain infrared spectra of different water concentrations. Based on the infrared spectra of water, determine the peak area of ​​the corresponding characteristic peak. Specifically, select the characteristic peak of water at 1640 cm⁻¹. -1 A standard curve for water is established with water concentration as the ordinate and the peak area of ​​the corresponding characteristic peak as the abscissa.

[0052] Referring to the process of establishing the standard curve for water, the standard curve for ammonia (931 cm⁻¹) was established. -1 ), hydrolysis products (1080 cm) -1 The standard curve is obtained, passing through the origin, and the correction coefficient is calculated. After the test, all valves are reset, three-way valve I 17 and three-way valve II 21 are closed, diaphragm valve III 18 is opened, and gas replacement device 13 is started to perform a "vacuuming-introduction of dry inert gas" cycle replacement 3 times before closing. After the last vacuuming, background data is collected and the background spectrum is saved.

[0053] 4. Initial monitoring of distillation sample: Open the sampling valve of distillation unit 3, and turn on the temperature control function of section 34 of the sample gas delivery line 14 (which is a heated cable), setting the temperature control to 60℃; open pressure reducing valve I 15, with an output pressure range of 1 bar; keep ports a and b connected with three-way valve I 17, and open diaphragm valves I 16, III 18, IV 19, and needle valve I 20; keep ports b and c connected with three-way valve II 21. The sample gas output from distillation unit 3 enters the gas recovery device 12 through gas cell 7. After 8 minutes, adjust needle valve I 20 by about 1.5 turns until the pressure sensor II 22 reads 0.075 bar. Reset all valves, and start FT-IR detection.

[0054] 5. Continuous monitoring method 1 during distillation: Open the sampling valve of distillation unit 3, activate the temperature control function of section 34 (heated cable) in sample gas delivery pipeline 14, maintaining the temperature at 60℃, open pressure reducing valve I 15, maintaining the output pressure at 1 bar, keep ports a and b connected in three-way valve I 17, keep diaphragm valves I 16, III 18, and IV 19 open, adjust the opening of needle valve I 20 to make the reading of pressure sensor II 22 0.075 bar, keep needle valve II 24 at a certain opening, and keep ports b and c connected in three-way valve II 21. In this state, gas in gas cell 7 can be sampled and analyzed in real time, with a maximum frequency of 75 times / hour.

[0055] 6. Continuous monitoring method 2 during distillation: Perform 6-1 before sample testing and 6-2 when preparing for monitoring. For each new time point sample test, first perform 6-1, then perform 6-2.

[0056] 6-1: Open the sampling valve of the distillation apparatus 3, open diaphragm valve II 31 and three-way valve I 17 to keep ports a and b connected, open diaphragm valve III 18, turn on the gas replacement device 13, and evacuate the original sample gas in the gas cell 7. After evacuating for 8 minutes, the pressure in the gas cell 7 is -25 kPa. Reset all valves.

[0057] 6-2: Open pressure reducing valve I 15, output pressure range 1 bar; keep ports a and b connected with three-way valve I 17, open the temperature control function of section 34 of the sample gas delivery line 14 (which is a heated cable), and keep the temperature at 60℃; open diaphragm valve III 18, diaphragm valve IV 19, and needle valve I 20, keep ports b and c connected with three-way valve II 21, the sample gas output from distillation unit 3 enters the gas recovery device through gas cell 7, adjust needle valve I 20 after 5 minutes, the pressure sensor II 22 reads 0.075 bar, all valves reset, and FT-IR detection begins.

[0058] 7. Instrument detection and data processing: The infrared spectrum of the sample to be tested is obtained. The characteristic peaks of the infrared spectrum of the distillation sample are calibrated, the peak areas are recorded, and the concentration is calculated through the correction coefficient.

[0059] The specific results of sample gas detection at a certain time point using "Continuous Monitoring Method 1 during Distillation" are shown in Table 1 below: Table 1

[0060] The specific results of sample gas detection at a certain time point using "Continuous Monitoring Method 2 during Distillation" are shown in Table 2 below:

[0061] The technical solution provided by this utility model has at least the following beneficial effects: 1. The device provided by this utility model enables the monitoring of ammonia, water, and / or hydrolysis product content during the distillation of silane. It allows for simultaneous online monitoring of these contents, facilitating accurate analytical data to guide process control and improve production efficiency. This facilitates efficient monitoring of the silane distillation process, promotes process optimization, and helps ensure production safety, achieve process controllability and batch stability, and further optimize the process.

[0062] 2. The device provided by this utility model can accurately and efficiently perform infrared monitoring of ammonia, water and hydrolysis products (such as hydrolysis products with Si-O-Si structure) in the silane system.

[0063] 3. All pipelines, devices, and components related to the testing process are placed inside the flow measurement chamber. The inert gas supply unit ensures a continuous flow of dry inert gas within the positive pressure flow measurement chamber, maintaining positive pressure. This positive pressure flow design, coupled with a dew point meter for real-time monitoring of chamber moisture, minimizes the interference of environmental moisture on the test results and improves the accuracy of the test data.

[0064] 4. The device provided by this utility model can flexibly adjust the monitoring method according to the needs, which helps to meet the process requirements at different stages and has strong flexibility and practicality.

[0065] It is readily understood that the above embodiments are merely illustrative examples for clear explanation and do not imply that the present invention is limited thereto. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. An apparatus for monitoring the content of ammonia, water, and / or hydrolysis products during the distillation of silane, characterized in that, The device includes a sample gas delivery pipeline (14) and a positive pressure flow measurement chamber (4), and also includes a tail gas treatment device (11), a gas recovery device (12), a calibration gas supply device (10) for supplying the required calibration gas, a gas replacement device (13), a three-way valve I (17), a three-way valve II (21), and a Fourier transform infrared spectrometer (6) equipped with a gas cell (7) in the positive pressure flow measurement chamber (4). The positive pressure flow measurement chamber (4) is equipped with an inert gas supply unit, which is used to continuously circulate dry inert gas in the positive pressure flow measurement chamber (4) and make the positive pressure flow measurement chamber (4) reach a preset positive pressure value; the positive pressure flow measurement chamber (4) is equipped with a moisture content analyzer (8) for detecting moisture content. One end of the sample gas delivery pipeline (14) is connected to the sample gas outlet of the distillation apparatus (3), and the other end extends into the positive pressure flow measurement chamber (4) and is connected to port a of the three-way valve I (17). The sample gas delivery pipeline (14) is equipped with a diaphragm valve I (16). The inlet of the gas pool (7) is connected to port b of the three-way valve I (17) via the first pipeline (29); the calibration gas supply device (10) is connected to port c of the three-way valve I (17) via the second pipeline (28). The gas replacement device (13) is connected to the first pipeline (29) via the third pipeline (30). The gas replacement device (13) is used to evacuate the pipeline and device connected to it and to replace them with inert gas. The exhaust outlet of the gas pool (7) is connected to port b of the three-way valve II (21) via the fourth pipeline (32), the exhaust gas treatment device (11) is connected to port a of the three-way valve II (21), and port c of the three-way valve II (21) is connected to the gas recovery device (12). Diaphragm valve III (18), diaphragm valve II (31), and diaphragm valve IV (19) are respectively installed on the first pipeline (29), the third pipeline (30), and the fourth pipeline (32).

2. The apparatus for monitoring the content of ammonia, water, and / or hydrolysis products during the distillation of silane according to claim 1, characterized in that, The section of the sample gas delivery pipeline (14) located between port a of the diaphragm valve I (16) and the three-way valve I (17) is connected to the gas recovery device (12) via the fifth pipeline (23).

3. The apparatus for monitoring the content of ammonia, water, and / or hydrolysis products during the distillation of silane according to claim 2, characterized in that, The fifth pipeline (23) is equipped with needle valve II (24).

4. The apparatus for monitoring the content of ammonia, water, and / or hydrolysis products during the distillation of silane according to claim 1, characterized in that, The sample gas delivery pipeline (14) is equipped with a pressure reducing valve I (15); The fourth pipeline (32) is also equipped with a needle valve I (20).

5. The apparatus for monitoring the content of ammonia, water, and / or hydrolysis products during the distillation of silane according to any one of claims 1-4, characterized in that, The sample gas delivery pipeline (14) is at least a section near the sample gas outlet of the distillation apparatus (3) that is a heat tracing cable with heating and temperature control functions; the second pipeline (28) is a heat tracing cable with heating and temperature control functions.

6. The apparatus for monitoring the content of ammonia, water, and / or hydrolysis products during the distillation of silane according to any one of claims 1-4, characterized in that, The positive pressure flow measurement chamber (4) is equipped with a heater (5) and a pressure sensor I (9).

7. The apparatus for monitoring the content of ammonia, water, and / or hydrolysis products during the distillation of silane according to any one of claims 1-4, characterized in that, The moisture content measuring instrument (8) is a dew point meter.

8. The apparatus for monitoring the content of ammonia, water, and / or hydrolysis products during the distillation of silane according to any one of claims 1-4, characterized in that, The inert gas supply unit includes an inert gas source (1), a drying column (2) for drying and removing moisture from the inert gas output from the inert gas source (1), an inert gas delivery pipeline (27), and an inert gas output pipeline (33). The inert gas source (1) is connected to the inlet of the positive pressure flow measuring chamber (4) through the inert gas delivery pipeline (27); the drying column (2) is provided on the inert gas delivery pipeline (27); the pressure reducing valve II (26) is also provided on the inert gas delivery pipeline (27); The inert gas output line (33) is connected to the outlet of the positive pressure flow measuring chamber (4), and a needle valve III (25) is provided on the inert gas output line (33).

9. The apparatus for monitoring the content of ammonia, water, and / or hydrolysis products during the distillation of silane according to any one of claims 1-4, characterized in that, The gas pool (7) is equipped with pressure sensor II (22); And / or, the gas pool (7) has heating and temperature control functions; And / or, the optical path length of the gas cell (7) is 5-30m; And / or, the Fourier transform infrared spectrometer (6) is also equipped with a vacuum optical stage and an MCT detector.

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