A high-precision proportioning ethylsilane mixed gas dissolving mixing system and control method

Abstract

The application discloses a high-precision proportioning ethylsilane mixed gas dissolving and mixing system and a control method, relates to the technical field of mixing equipment, and comprises a raw material storage module, which is three stainless steel storage tanks respectively storing ethylsilane, dilution gas and solvent, and is provided with a passivated inner wall and an outer heat preservation layer; a precise metering module, which is provided with a plunger pump and a mass flowmeter for real-time feedback of flow; a dissolving and mixing module, which is a double-layer jacketed tank provided with an atomizing nozzle and double-layer inclined blade reverse stirring paddles; a temperature and pressure control module, which comprises a jacketed temperature control device and a tank top pressure relief valve; a concentration monitoring module, which is provided with an online laser Raman spectrometer; a tail gas treatment module, which is composed of an adsorption tower and a catalytic combustor; and a central control module, which realizes full-process automatic control by using a PLC and a touch screen, and each module cooperates to complete the preparation of mixed gas. The application improves the proportioning precision and dissolving efficiency of ethylsilane mixed gas, stabilizes the concentration drift, realizes environmental protection of tail gas treatment, and is suitable for high-precision requirements in multiple scenes and provides stable raw materials for downstream processes.

Description

Technical Field

[0001] This invention relates to the field of mixing equipment technology, and in particular to a high-precision proportioning silane gas dissolution mixing system and control method. Background Technology

[0002] As a core raw material in high-precision manufacturing scenarios such as semiconductor thin film deposition and photovoltaic cell coating, the accuracy of silane mixture directly determines the performance indicators of downstream products, requiring strict control of silane concentration deviation within an extremely low range. However, existing silane mixture dissolution and mixing systems have significant technical shortcomings in the raw material processing stage: raw material storage often adopts a single tank design, with silane, dilution gas, and solvent stored in separate containers without pressure coordination control. The pressure inside the tank fluctuates greatly due to the influence of ambient temperature and the remaining amount of raw material, causing the flow rate of the metering pump to fluctuate. In particular, silane is prone to liquefaction at low temperatures, and direct delivery without preheating will cause cavitation in the metering pump chamber, further amplifying the flow deviation. Although some systems are equipped with mass flow meters, they can only passively feedback flow data and lack a dynamic correction mechanism based on concentration deviation. This cannot offset the metering errors caused by pump wear and changes in pipeline resistance during long-term operation, ultimately leading to deviations in the raw material ratio from the set value.

[0003] Technical deficiencies in the dissolution and mixing process further restrict the accuracy and efficiency of proportioning: Traditional mixing tanks mostly use single-layer impellers with a single stirring direction, making it difficult for silane gas and solvent to form effective convection, easily leading to "stratification" phenomena with localized excessively high or low concentrations. Furthermore, the feed inlet lacks atomization design, with silane directly entering the solvent in the form of bubbles, resulting in slow dissolution and incomplete dissolution. Temperature and pressure control often employs coarse-grained regulation, with mixing tanks lacking jacketed temperature control or only capable of fixed temperature control, failing to dynamically adjust the temperature based on the exothermic dissolution characteristics of silane. This results in temperature fluctuations within the tank exceeding ±2℃, and temperature changes directly affect the solubility of silane in the solvent. Concentration monitoring relies on offline sampling and analysis using gas chromatography, with a single detection taking more than 5 minutes. The detection results lag behind the mixing process, and even if concentration deviations are detected, a large amount of substandard mixed gas has already been generated, making real-time intervention and adjustment impossible.

[0004] The system also suffers from shortcomings in reliability and environmental friendliness: the activated carbon adsorption tower in the exhaust gas treatment module lacks a regeneration function, requiring complete replacement once the activated carbon is saturated. This not only increases maintenance costs but also poses a safety risk due to unreacted silane leakage during replacement; the precision metering module is equipped with only a single metering pump, requiring shutdown for repairs in case of pump failure, interrupting the mixing process and affecting production continuity; the emergency safety control mechanism is inadequate, only triggering alarms when the mixing tank exceeds temperature or pressure, failing to automatically cut off raw material delivery and depressurize. As silane is a flammable and explosive gas, overpressure poses a safety hazard of tank rupture and gas leakage. These technical shortcomings collectively make it difficult for the existing system to meet the requirements for high-precision, high-reliability, and high-environmental-friendliness silane mixture preparation, becoming a key bottleneck restricting the high-quality development of industries such as semiconductors and photovoltaics. Summary of the Invention

[0005] This invention proposes a high-precision silane mixed gas dissolution mixing system and control method to solve the problems mentioned in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a high-precision proportioning silane mixed gas dissolution mixing system, comprising the following modules: The raw material storage module consists of three independent stainless steel storage tanks, which store silane, dilution gas and solvent respectively. The inner wall of the storage tank is electrochemically passivated. The top is equipped with an inert gas inlet and a pressure monitoring port, the bottom is equipped with a discharge port with a shut-off valve, and the outside is wrapped with a polyurethane insulation layer. The precision metering module is equipped with one high-precision plunger pump for each of the three storage tanks, and a mass flow meter is connected in series at the outlet of each pump to provide real-time feedback on the delivery flow to the subsequent central control module. The dissolving and mixing module adopts a double-layer jacketed mixing tank with three raw material inlets at the top, atomizing nozzles installed at the inlets, a double-layer inclined blade reverse stirring paddle in the middle, and a mixed gas outlet at the bottom of the tank. The jacket layer can be circulated with a temperature control medium. The temperature and pressure control module includes a temperature control unit and a pressure control unit. The temperature control unit is equipped with an electric regulating valve and a platinum resistance temperature sensor at the inlet of the mixing tank jacket. The pressure control unit is equipped with a pressure sensor and a safety relief valve at the top of the mixing tank. The concentration monitoring module is equipped with an online laser Raman spectrometer at the outlet of the mixing tank. It collects the actual concentration value of silane in the mixed gas every 2 seconds, and the detection data is transmitted to the central control module in real time. The exhaust gas treatment module consists of an activated carbon adsorption tower and a catalytic burner. The adsorption tower is filled with columnar activated carbon, with its inlet connected to the exhaust port of the mixing system and its outlet connected to the catalytic burner. The central control module uses a PLC controller and a touch screen. The PLC has analog input / output and digital input / output functions, and can receive relevant data from each module and output control signals to the corresponding actuators.

[0007] Furthermore, it also includes a raw material preheating module. This module is equipped with one tubular preheater for each of the silane and solvent storage tanks. The raw material flows through the tube side, and hot water is introduced into the shell side as the heating medium. A temperature sensor is installed at the inlet and a flow regulating valve is installed at the outlet. Depending on the type of raw material, the silane is preheated to 5-10°C and the solvent is preheated to 15-25°C, which reduces the loss of dissolution efficiency caused by the sudden temperature change after the low-temperature raw material enters the mixing tank.

[0008] Furthermore, it also includes a pressure balancing module, which consists of a 10L nitrogen buffer tank and three pressure regulating valves. The outlet of the buffer tank is connected to the inert gas inlets of the silane, dilution gas, and solvent storage tanks through pipelines, respectively. It can regulate the pressure of the three raw material storage tanks to 0.3-0.5MPa, with a pressure deviation of ≤±0.02MPa for each tank.

[0009] Furthermore, the double-layer inclined blade agitator of the dissolution and mixing module has a special structural design. The diameter of the upper agitator is 1 / 2 of the inner diameter of the mixing tank and the blade tilt angle is 45°. The diameter of the lower agitator is 2 / 3 of the inner diameter of the mixing tank and the blade tilt angle is 60°. The two agitators rotate in opposite directions, with the upper one rotating clockwise and the lower one rotating counterclockwise, which can form an upper and lower convection mixing flow field inside the tank.

[0010] Furthermore, the concentration monitoring module is also equipped with a concentration deviation alarm unit. When the online laser Raman spectrometer detects that the actual concentration of silane deviates from the set concentration by more than ±0.05%, the alarm unit issues an audible and visual alarm signal and transmits the deviation signal to the central control module, which then automatically triggers the metering flow adjustment process.

[0011] Furthermore, the activated carbon adsorption tower of the exhaust gas treatment module is equipped with an adsorbent regeneration unit. The regeneration unit consists of a hot nitrogen generator and a flow control valve. When the pressure difference between the inlet and outlet of the adsorption tower exceeds 0.1 MPa, it is determined that the activated carbon has reached the adsorption saturation state. The central control module automatically closes the inlet valve of the adsorption tower, turns on the hot nitrogen generator, and introduces hot nitrogen at a temperature of 120-150℃ to regenerate the activated carbon. The gas containing silane generated during the regeneration process is introduced into the catalytic burner for treatment. After the regeneration is completed, the hot nitrogen is turned off, and the adsorption function is restored after the temperature of the adsorption tower drops to room temperature.

[0012] Furthermore, the metering module is also equipped with a dual-pump redundancy unit. Each high-precision plunger pump corresponding to each raw material is connected in parallel with a standby pump. The central control module monitors the operating current and outlet pressure of the main pump in real time. When the main pump current exceeds the rated value by 10% or the outlet pressure fluctuates by more than ±0.02MPa, it automatically switches to the standby pump and triggers the main pump fault alarm signal at the same time.

[0013] Furthermore, a control method for a high-precision proportioning silane gas dissolution and mixing system, utilizing a system comprising a raw material storage module, a precise metering module, a dissolution and mixing module, a temperature and pressure control module, a concentration monitoring module, an exhaust gas treatment module, and a central control module, includes the following steps: In the raw material preparation step, the target ratio of silane, dilution gas and solvent is set through the central control module, the pressure balance module is started to regulate the pressure of the three raw material storage tanks to 0.3-0.5MPa, and the raw material preheating module is started at the same time. In the precise metering step, the central control module calculates the theoretical conveying flow rate of each raw material according to the target ratio, sends a control signal to the plunger pump of the precise metering module, starts the main pump to convey the raw materials, and the mass flow meter collects the actual conveying flow rate in real time and feeds it back to the central control module. In the preheating adjustment step, the metered silane and solvent are fed into the tubular preheater of the raw material preheating module. By adjusting the shell-side hot water temperature of the preheater, the silane outlet temperature is maintained at 5-10℃ and the solvent outlet temperature is maintained at 15-25℃. In the dissolution and mixing step, the preheated silane, solvent and dilution gas are sprayed into the tank through the atomizing nozzle at the top of the mixing tank. The double-layer inclined blade stirring paddle is started and the speed is dynamically adjusted according to the solvent viscosity. After the dilution gas is introduced, the speed is adjusted to 200-300 r / min. At the same time, the temperature control unit is started. The concentration monitoring process involves an online laser Raman spectrometer detecting the actual concentration of silane at the outlet of the mixing tank every 2 seconds and transmitting the detection data to the central control module. In the exhaust gas treatment process, a small amount of exhaust gas generated during the mixing process is introduced into the exhaust gas treatment module through a pipeline. The unreacted silane is first adsorbed by the activated carbon adsorption tower. The adsorbed gas then enters the catalytic burner and is heated to completely burn the residual silane. The system cleaning steps are as follows: After the mixing task is completed, close the shut-off valve of the raw material storage tank, stop the metering pump and the stirring motor, start the cleaning process through the central control module, purge the mixing tank with inert gas, then rinse the tank wall with solvent, and then guide the rinsed solvent into the waste liquid collection tank. Finally, purge the tank with inert gas again until it is dry.

[0014] Furthermore, a proportioning accuracy correction process is introduced into the precise metering step. When there is a continuous deviation between the actual flow rate and the theoretical flow rate reported by the mass flow meter, the error is corrected using a formula. Calculate the corrected metered flow rate, where The corrected raw material flow rate, The theoretical flow rate before correction. The flow correction factor is set to a value of 0.8-1.2. This refers to the deviation between the actual concentration detected by the concentration monitoring module and the set concentration. This is the set concentration value for the silane mixture.

[0015] Furthermore, it also includes an emergency shutdown control process. When the temperature and pressure control module detects that the temperature inside the mixing tank exceeds 35°C or the pressure exceeds 0.6MPa, the central control module immediately triggers an emergency shutdown command. First, it closes the bottom shut-off valve and metering pump of the raw material storage tank, then closes the discharge valve of the mixing tank, opens the top pressure relief valve, and at the same time starts the emergency exhaust channel of the exhaust gas treatment module to quickly introduce the residual gas in the tank into the catalytic burner for treatment until the temperature and pressure return to the normal range.

[0016] Compared with existing technologies, the beneficial effects of this invention are: This invention achieves technological breakthroughs in multiple dimensions, including raw material processing, dissolution and mixing, concentration monitoring, exhaust gas treatment, and system reliability, significantly improving the precision, efficiency, and safety of dissolution and mixing of silane mixtures. Its core advantages are as follows: Optimization of the raw material handling process lays the foundation for accurate proportioning. The raw material storage module reduces the interference of environmental factors on the raw material state through passivation treatment of the inner wall of the storage tank and the design of the insulation layer; the pressure balancing module stabilizes the pressure of each storage tank within the same range, eliminating metering fluctuations caused by pressure differences; the raw material preheating module preheats the raw materials according to the characteristics of silane and solvents, avoiding cavitation of the metering pump and loss of dissolution efficiency caused by low-temperature raw materials; the dual-pump redundancy design and proportioning accuracy correction process of the precision metering module not only ensures uninterrupted metering but also dynamically adjusts the flow rate according to concentration deviations, significantly reducing metering errors and improving the accuracy of raw material proportioning from the source.

[0017] Innovations in the dissolution and mixing process significantly improve mixing uniformity and efficiency. A double-jacketed mixing tank, combined with atomizing nozzles, disperses silane in the solvent as microbubbles, shortening dissolution time. Opposite-rotating double-layered inclined blades create an upward-downward convection flow field, effectively mitigating the "stratification" problem of traditional single-layer stirring and ensuring uniform mixing of silane and solvent. A temperature and pressure control module dynamically adjusts the jacket medium temperature and tank pressure in real time, adapting to the exothermic dissolution characteristics of silane to maintain a stable dissolution environment, avoiding the impact of temperature and pressure fluctuations on solubility, and further ensuring stable mixed gas concentration.

[0018] Upgrades to concentration monitoring and exhaust gas treatment enable precise control and environmentally friendly operation. An online laser Raman spectrometer collects concentration data in real time, and with deviation alarms and automatic adjustment functions, it can quickly respond to concentration deviations, preventing the generation of unqualified gas mixtures. The activated carbon regeneration unit in the exhaust gas treatment module eliminates the need for frequent adsorbent replacement, reducing maintenance costs and minimizing the risk of silane leakage. The catalytic burner ensures that unreacted silane is completely converted into harmless products, meeting environmental protection requirements.

[0019] Enhanced system reliability and safety meet the demands of continuous production. The dual-pump redundancy design avoids downtime caused by single-pump failure, improving production continuity. The emergency shutdown control process automatically cuts off raw material delivery, depressurizes, and handles residual gas in cases of over-temperature or over-pressure, completely eliminating safety hazards. Overall, this invention achieves "precise proportioning, efficient mixing, safety, environmental protection, and stable operation" of silane mixtures, effectively addressing the multi-dimensional technical shortcomings of existing systems and providing reliable raw material preparation support for high-precision manufacturing scenarios. Attached Figure Description

[0020] Figure 1 This is a schematic block diagram of a high-precision proportioning silane mixed gas dissolution mixing system proposed in this invention; Figure 2 This is a schematic block diagram of a control method for a high-precision proportioning silane mixed gas dissolution mixing system proposed in this invention. Figure 3 A bar chart comparing the accuracy of silane mixture ratios in different application scenarios; Figure 4 This is a line graph showing the dissolution time of silane as a function of stirring speed. Figure 5 A line graph showing the change in concentration drift of the silane mixture over operating time; Figure 6 A bar chart comparing emergency stop response times under different fault types. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installed," "connected," and "linked" should be interpreted broadly; for example, they may refer to a fixed connection, a detachable connection, or an integral connection; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; and they may refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances. The invention will now be described in further detail with reference to the accompanying drawings.

[0024] Reference Figures 1 to 6 A high-precision silane mixture gas dissolution mixing system, comprising the following modules: The raw material storage module consists of three independent stainless steel storage tanks, which store silane, dilution gas (argon or nitrogen) and solvent (n-hexane or cyclohexane) respectively. The inner wall of the storage tank is electrochemically passivated, and the top is equipped with an inert gas inlet and a pressure monitoring port, while the bottom is equipped with a discharge port with a shut-off valve. The outside is wrapped with a polyurethane insulation layer to reduce the interference of ambient temperature fluctuations on the state of the raw materials. The precision metering module is equipped with one high-precision plunger pump for each of the three storage tanks, with a flow rate adjustment range of 0.1-10L / h and an accuracy class of 0.1. Each pump outlet is connected in series with a mass flow meter with a measurement range of 0.05-15kg / h and a response time of ≤0.5 seconds, which provides real-time feedback of the actual delivery flow rate to the subsequent central control module. The dissolution and mixing module adopts a double-jacketed mixing tank with an inner volume of 50-200L. It has three raw material inlets at the top (connected to silane, dilution gas, and solvent metering outlets respectively), atomizing nozzles installed at the inlets, a double-layered oblique blade counter-stirring paddle in the middle with a speed adjustment range of 50-500r / min, a mixed gas outlet at the bottom of the tank, and a temperature control medium can be introduced into the jacket layer. The temperature and pressure control module includes a temperature control unit and a pressure control unit. The temperature control unit is equipped with an electric regulating valve and a platinum resistance temperature sensor at the inlet of the mixing tank jacket, with a measurement range of -20℃ to 80℃ and an accuracy of ±0.1℃, to control the temperature of the jacket medium in real time. The pressure control unit is equipped with a pressure sensor and a safety relief valve at the top of the mixing tank, with a measurement range of 0-1MPa and an accuracy of ±0.005MPa. The opening pressure of the relief valve is set to 0.8MPa to limit the pressure inside the tank from exceeding the safety threshold. The concentration monitoring module is equipped with an online laser Raman spectrometer installed at the outlet of the mixing tank. The detection wavelength range is 532-1064nm (resolution ≤0.1nm), and the concentration measurement accuracy is ±0.01%. The actual concentration value of silane in the mixed gas is collected every 2 seconds, and the detection data is transmitted to the central control module in real time. The exhaust gas treatment module consists of an activated carbon adsorption tower and a catalytic burner. The adsorption tower is filled with columnar activated carbon with a particle size of 3-5mm. The inlet is connected to the exhaust port of the mixing system, and the outlet is connected to the catalytic burner. The burner adopts an electric heating method with an ignition temperature ≥300℃, so that unreacted silane is completely burned into silicon dioxide and water. The central control module consists of a PLC controller and a touch screen. The PLC has analog and digital input / output functions. It can receive flow data from the metering module, temperature and pressure data from the temperature control module, and concentration data from the concentration monitoring module. It outputs control signals to the metering pump, stirring motor, and temperature control valve. Based on the collected data, it realizes full-process automated control. The touch screen supports parameter setting, status display, and historical data query.

[0025] This invention also includes a raw material preheating module, which is equipped with one tubular preheater for each of the silane and solvent storage tanks. The preheater is made of 316L stainless steel, with the raw material flowing through the tube side and hot water flowing through the shell side as the heating medium. A temperature sensor is installed at the inlet and a flow regulating valve is installed at the outlet. It can preheat the silane to 5-10°C and the solvent to 15-25°C according to the type of raw material, thereby reducing the loss of dissolution efficiency caused by the sudden temperature change after the low-temperature raw material enters the mixing tank. The outer wall of the preheater is wrapped with aluminum silicate insulation cotton to reduce heat loss and maintain a stable preheating temperature.

[0026] This invention also includes a pressure balancing module, which consists of a 10L nitrogen buffer tank and three pressure regulating valves. The outlet of the buffer tank is connected to the inert gas inlets of the silane, dilution gas, and solvent storage tanks via pipelines. Each pressure regulating valve on the connecting pipeline has an accuracy class of 0.2 and supports pressure regulation at the 0.01MPa level. This can stabilize the pressure of the three raw material storage tanks at 0.3-0.5MPa (deviation ±0.02MPa), reduce the interference of pressure differences between the storage tanks on the flow rate delivered by the metering pump, and improve the metering accuracy of the raw materials.

[0027] In this invention, the double-layer inclined blade agitator of the dissolution and mixing module has a special structural design. The diameter of the upper agitator is 1 / 2 of the inner diameter of the mixing tank (deviation ±2mm) and the blade tilt angle is 45°. The diameter of the lower agitator is 2 / 3 of the inner diameter of the mixing tank (deviation ±2mm) and the blade tilt angle is 60°. The two agitators rotate in opposite directions, with the upper one rotating clockwise and the lower one rotating counterclockwise. This can form an upward and downward convection mixing flow field in the tank, shortening the dissolution time of silane and solvent. The connection between the agitator shaft and the tank wall is made of polytetrafluoroethylene mechanical seal to prevent the mixed gas from leaking from the gap between the shaft and the tank wall.

[0028] In this invention, the concentration monitoring module is also equipped with a concentration deviation alarm unit. When the online laser Raman spectrometer detects that the actual concentration of silane deviates from the set concentration by more than ±0.05%, the alarm unit issues an audible and visual alarm signal and transmits the deviation signal to the central control module. The central control module automatically triggers the metering flow adjustment process and adjusts the delivery flow of the silane metering pump to regulate the actual concentration to the set range. The alarm signal continues until the concentration deviation drops below ±0.03% and then automatically terminates.

[0029] In this invention, the activated carbon adsorption tower of the exhaust gas treatment module is equipped with an adsorbent regeneration unit. The regeneration unit consists of a hot nitrogen generator and a flow control valve. When the pressure difference between the inlet and outlet of the adsorption tower exceeds 0.1 MPa, it is determined that the activated carbon has reached adsorption saturation. The central control module automatically closes the inlet valve of the adsorption tower, turns on the hot nitrogen generator, and introduces hot nitrogen at a temperature of 120-150℃. The nitrogen flow rate is controlled at 5-10 m³ / h. 3 / h (matched according to the adsorption tower volume ratio of 1:1.2) to regenerate activated carbon. The gas containing silane generated during the regeneration process is introduced into the catalytic burner for treatment. After the regeneration is completed, the hot nitrogen gas is turned off, and the adsorption function is restored after the adsorption tower temperature drops to room temperature.

[0030] In this invention, the precision metering module is also equipped with a dual-pump redundancy unit. Each high-precision plunger pump corresponding to each raw material is connected in parallel with a standby pump. The parameters of the standby pump and the main pump are completely consistent. The central control module monitors the operating current and outlet pressure of the main pump in real time. When the main pump current exceeds the rated value by 10% or the outlet pressure fluctuates by more than ±0.02MPa, it automatically switches to the standby pump and triggers the main pump fault alarm signal at the same time, so as to maintain the continuous operation of the raw material metering process and improve the reliability of the system operation.

[0031] This invention includes the following steps: In the raw material preparation step, the target ratio of silane, dilution gas and solvent is set through the central control module. The pressure balance module is activated to adjust the pressure of the three raw material storage tanks to 0.3-0.5MPa (deviation ±0.02MPa). At the same time, the raw material preheating module is activated to preheat the silane to 5-10℃ and the solvent to 15-25℃. After the preheating reaches the target, the bottom shut-off valve of the storage tank is opened. In the precise metering step, the central control module calculates the theoretical delivery flow rate of each raw material according to the target ratio, sends a control signal to the plunger pump of the precise metering module, starts the main pump to deliver the raw materials, and the mass flow meter collects the actual delivery flow rate in real time and feeds it back to the central control module. When the flow rate deviation exceeds ±0.1%, the pump speed is adjusted to regulate the actual flow rate to match the theoretical flow rate. In the preheating adjustment step, the metered silane and solvent are fed into the tubular preheater of the raw material preheating module. By adjusting the shell-side hot water temperature of the preheater, the silane outlet temperature is kept stable at 5-10℃ and the solvent outlet temperature is kept stable at 15-25℃. The dilution gas is directly delivered to the mixing tank. In the dissolution and mixing step, the preheated silane, solvent, and dilution gas are sprayed into the mixing tank through the atomizing nozzle at the top of the mixing tank. The double-layer inclined blade stirring paddle is started, and the speed is dynamically adjusted according to the solvent viscosity. When mixing silane and solvent, the speed is set to 300-400 r / min, and after the dilution gas is introduced, it is adjusted to 200-300 r / min. At the same time, the temperature control unit is started to control the temperature in the mixing tank at 20-30℃. The concentration monitoring process involves an online laser Raman spectrometer detecting the actual concentration of silane at the outlet of the mixing tank every 2 seconds and transmitting the detection data to the central control module. The central control module then compares the actual concentration with the set concentration and calculates the concentration deviation. In the exhaust gas treatment process, a small amount of exhaust gas generated during the mixing process is introduced into the exhaust gas treatment module through a pipeline. The unreacted silane is first adsorbed by the activated carbon adsorption tower. The adsorbed gas enters the catalytic burner and is heated to above 300°C to completely burn the residual silane. The combustion products are discharged through the exhaust pipe. The system cleaning steps are as follows: After the mixing task is completed, close the shut-off valve of the raw material storage tank, stop the metering pump and the stirring motor, start the cleaning process through the central control module, purge the mixing tank with inert gas for 3-5 minutes, then purge with solvent to rinse the tank wall, and the rinsed solvent is introduced into the waste liquid collection tank. Finally, purge with inert gas again until the tank is dry.

[0032] In this invention, a proportioning accuracy correction process is introduced into the precise metering step. When there is a continuous deviation between the actual flow rate and the theoretical flow rate fed back by the mass flow meter, the error is corrected using a formula. Calculate the corrected metered flow rate, where The corrected raw material flow rate, The theoretical flow rate before correction. The flow correction factor is set to a value of 0.8-1.2. This refers to the deviation between the actual concentration detected by the concentration monitoring module and the set concentration. This is the set concentration value for the silane mixture; through this calculation, the metering flow rate can be dynamically adjusted according to the actual concentration deviation, reducing the impact of metering error on the mixing accuracy, so that the final mixture concentration meets the process parameters.

[0033] This invention also includes an emergency shutdown control process. When the temperature and pressure control module detects that the temperature inside the mixing tank exceeds 35°C or the pressure exceeds 0.6MPa, the central control module immediately triggers an emergency shutdown command. First, it closes the bottom shut-off valve and metering pump of the raw material storage tank to stop the raw material delivery. Then, it closes the discharge valve of the mixing tank and opens the top pressure relief valve to regulate the pressure inside the tank to below 0.1MPa. At the same time, it starts the emergency exhaust channel of the exhaust gas treatment module to quickly introduce the residual gas in the tank into the catalytic burner for treatment. After the temperature and pressure return to the normal range, the cause of the fault is confirmed and eliminated through the touch screen before the system can be restarted.

[0034] The following two examples further illustrate the specific implementation of this system: Example 1: Preparation of silane mixture for semiconductor thin film deposition This embodiment is applied to the semiconductor chip thin film deposition process, which requires the preparation of a mixed gas with a concentration of 5% silane, 10% argon, and 85% n-hexane. The required ratio accuracy is ±0.03% and the dissolution time is ≤10 minutes. The deployment and operation details of each module of the system are as follows.

[0035] I. System Module Deployment and Parameter Configuration The raw material storage module comprises three 100-liter stainless steel tanks, storing silane, argon, and n-hexane respectively. The inner walls of the tanks undergo electrochemical passivation treatment with a passivation film thickness of 8 micrometers, and are wrapped with a 50-millimeter-thick polyurethane insulation layer. The inert gas inlet at the top of the silane tank is connected to a nitrogen pipeline, and a pressure sensor with an accuracy of ±0.002 MPa is installed at the pressure monitoring port. The bottom discharge port shut-off valve is pneumatically controlled with an opening response time of ≤0.3 seconds.

[0036] The precision metering module is equipped with three high-precision plunger pumps for each of the three storage tanks, with a flow rate adjustment range of 0.1-10 liters per hour and an adjustment step of 0.01 liters per hour. Each pump outlet is connected in series with a mass flow meter, with a measurement range of 0.05-15 kilograms per hour and an accuracy of 0.05%. A one-way valve is installed downstream of the flow meter to prevent raw material backflow. In the dual-pump redundancy unit, the standby pump and the main pump are connected in parallel via a three-way valve, with a switching time of ≤0.5 seconds. The central control module collects the main pump's operating current and outlet pressure in real time. The main pump has a rated current of 5 amps and a rated pressure of 0.6 MPa.

[0037] The dissolution and mixing module uses a 100-liter double-jacketed mixing tank. The tank's inner cavity is made of 316L stainless steel, and the inner wall is polished to a surface roughness Ra≤0.8 micrometers. Three inlets at the top correspond to silane, argon, and n-hexane, respectively, each equipped with a 0.5 mm orifice atomizing nozzle at a 60-degree atomization angle. A double-layered inclined blade agitator is installed in the middle of the tank. The upper blade has a diameter of 250 mm, half the tank's 500 mm inner diameter, with a 45-degree inclination. The lower blade has a diameter of 330 mm, two-thirds the tank's inner diameter, with a 60-degree inclination. The agitator shaft is a 20 mm diameter stainless steel shaft, and the connection to the tank wall uses a silicon carbide-graphite mechanical seal with a sealing pressure of 0.8 MPa. An electric regulating valve is installed at the jacket inlet with an adjustment accuracy of 0.1%, and a PT100 temperature sensor is installed at the outlet with an accuracy of ±0.1 degrees Celsius.

[0038] In the temperature and pressure control module, the temperature control unit maintains the temperature of the jacketed medium, deionized water, at 25 degrees Celsius. A PID algorithm is used to adjust the opening of the electric regulating valve, controlling temperature fluctuations within ±0.2 degrees Celsius. The pressure control unit has a pressure sensor installed on the top of the mixing tank, with a measurement range of 0-1 MPa and an accuracy of ±0.005 MPa. The safety relief valve has an opening pressure of 0.8 MPa and a relief port diameter of 10 mm.

[0039] The online laser Raman spectrometer of the concentration monitoring module has a detection wavelength of 532 nm and a resolution of 0.05 nm. The sampling point is located 100 mm downstream of the discharge port of the mixing tank. It outputs concentration data every 2 seconds. The concentration deviation alarm unit is set to trigger an audible and visual alarm when the deviation exceeds ±0.05%. The alarm sound pressure level is 80 dB and the light is red flashing.

[0040] The exhaust gas treatment module features a 50-liter activated carbon adsorption tower filled with 1.2-meter-high, 3-5 mm columnar activated carbon. Differential pressure sensors are installed at the inlet and outlet of the adsorption tower, with a measurement range of 0-0.2 MPa and an accuracy of ±0.001 MPa. The hot nitrogen generator outputs hot nitrogen at a temperature of 130 degrees Celsius and a flow rate of 8 cubic meters per hour. The catalytic burner has an electric heating power of 5 kW and an ignition temperature of 320 degrees Celsius. Combustion products are discharged through a 10-meter-high exhaust stack.

[0041] The central control module uses a medium-sized PLC and a 10-inch touch screen. The PLC has 16 analog inputs and 12 analog outputs, built-in data storage with a storage capacity of 8000 megabytes, supports historical data query, and can save data for up to three months. The touch screen displays real-time parameters such as flow rate, temperature, pressure, and concentration, and supports manual / automatic mode switching.

[0042] II. Control Flow and Formula Application Raw material preparation steps: The central control module sets the target ratio: 5% silane, 10% argon, and 85% hexane. The pressure balancing module is activated, and the nitrogen buffer tank pressure is adjusted to 0.4 MPa. The pressure of the three storage tanks is stabilized at 0.4 ± 0.02 MPa through regulating valves. The raw material preheating module is activated. The shell-side hot water temperature of the silane preheater is controlled at 8 degrees Celsius, ensuring a stable silane outlet temperature of 8 degrees Celsius. The shell-side hot water temperature of the solvent preheater is controlled at 20 degrees Celsius, ensuring a stable hexane outlet temperature of 20 degrees Celsius. After preheating reaches the target, the bottom shut-off valve of the storage tank is opened.

[0043] Precise metering steps: The total flow rate is set to 10 liters per hour. Based on the target ratio, the theoretical flow rates are calculated: 0.5 liters per hour for silane, 1.0 liter per hour for argon, and 8.5 liters per hour for n-hexane. The central control module sends a control signal to the plunger pump, starting the main pump. The mass flow meter reports an actual silane flow rate of 0.51 liters per hour, with a deviation exceeding ±0.1% for 5 seconds. Simultaneously, the concentration monitoring module detects an actual concentration of 5.1%. At this point... The difference between the set concentration and the actual concentration is calculated as 5% - 5.1% = -0.1%. C represents the set concentration of the silane mixture at 5%. Set the flow correction factor to 1.0 and substitute it into the formula. Calculated =0.5×(1+1.0×(-0.1) / 5)=0.5×0.98=0.49 liters per hour. After adjustment, the silane flow rate drops to 0.49 liters per hour, and the concentration returns to 5.0% after 5 seconds.

[0044] Dissolution and mixing steps: The raw materials are sprayed into the mixing tank through an atomizing nozzle. The stirring paddle is started, and the stirring speed is set to 350 rpm during the mixing stage of silane and n-hexane. After argon gas is introduced, the speed is adjusted to 250 rpm. Deionized water at 25 degrees Celsius is introduced into the jacket layer, and the temperature inside the tank is stabilized at 25 ± 0.2 degrees Celsius, and the pressure is stabilized at 0.3 MPa.

[0045] Concentration monitoring and exhaust gas treatment: The spectrometer detects the concentration every 2 seconds, with the deviation controlled within ±0.02%. 0.5 cubic meters of exhaust gas per hour generated during the mixing process is introduced into an activated carbon adsorption tower. After adsorption, the gas enters a catalytic burner at a combustion temperature of 320 degrees Celsius, with a silane combustion efficiency of 99.9%.

[0046] System cleaning steps: After mixing, close the shut-off valve, stop the pump and agitator, purge with nitrogen for 4 minutes, then purge with n-hexane to rinse the tank wall at a flow rate of 5 liters per hour for 3 minutes. Purge the rinsing liquid into the waste tank, and finally purge with nitrogen until the humidity inside the tank is ≤5%.

[0047] III. Data Representation and Interpretation Table 1 Comparison of key performance indicators between the conventional system and this system for preparing mixed gases for semiconductors.

[0048] Table 1 shows that traditional systems lack pressure balancing and metering correction mechanisms, resulting in a mixing accuracy of only ±0.2%. The single-layer agitator and lack of atomization design lead to a silane dissolution time of up to 25 minutes, and offline concentration detection causes concentration deviation fluctuations of ±0.3%. The exhaust gas treatment lacks activated carbon regeneration, resulting in a silane residue of 50 ppm in the exhaust gas. The single-metering pump design leads to an 8% annual downtime rate. This system stabilizes tank pressure through a pressure balancing module and dynamically adjusts flow rate using a metering correction formula, improving mixing accuracy to ±0.02%. The combination of atomizing nozzles and a double-layer counter-current agitator shortens the dissolution time to 8 minutes. Online concentration monitoring and real-time control keep concentration deviation fluctuations within ±0.02%. The activated carbon regeneration unit and catalytic burner work together to reduce silane residue in the exhaust gas to 0.5 ppm. The dual-pump redundancy design reduces the annual downtime rate to 0.5%, perfectly meeting the stringent requirements of semiconductor processes for high precision and stability in gas mixtures.

[0049] Example 2: Preparation of silane mixture for photovoltaic cell coating This embodiment is applied to the antireflective coating process of photovoltaic cells. It requires the preparation of a mixed gas with 1% silane, 10% nitrogen, and 89% cyclohexane. The low concentration ratio accuracy is required to be ±0.01%, and the activated carbon regeneration efficiency is required to be ≥90%. The system modules are adjusted to adapt to low concentration scenarios as follows.

[0050] I. System Module Deployment and Parameter Configuration The raw material storage module uses three 50-liter stainless steel storage tanks. The passivation film on the inner wall of the silane storage tank is 5 micrometers thick, and the insulation layer is 40 millimeters thick. The original argon storage tank is replaced with a nitrogen storage tank, and the original n-hexane storage tank is replaced with a cyclohexane storage tank. The pressure monitoring accuracy of the storage tanks is ±0.003 MPa.

[0051] The precision metering module plunger pump has a flow rate adjustment range of 0.05-5 liters per hour, which is suitable for low-concentration and low-flow requirements. The lower limit of the mass flow meter measurement is reduced to 0.02 kg per hour. The dual-pump redundancy unit switching threshold is set to the main pump current exceeding the rated value by 8% or the outlet pressure fluctuation by ±0.015 MPa. The rated current of the main pump is 4 amps.

[0052] The dissolving and mixing module uses a 50-liter double-jacketed mixing tank with an inner diameter of 380 mm. The upper stirring paddle has a diameter of 190 mm, which is half the inner diameter of the tank, and rotates at 250 rpm. The lower stirring paddle has a diameter of 250 mm, which is two-thirds the inner diameter of the tank, and rotates at 200 rpm. The atomizing nozzle has an orifice diameter of 0.3 mm and an atomization angle of 45 degrees. The jacket medium is 15-degree Celsius deionized water, maintaining the temperature inside the tank at 20 ± 0.2 degrees Celsius.

[0053] The temperature and pressure control module has a pressure sensor with a measurement range of 0-0.8 MPa, a safety relief valve with an opening pressure of 0.6 MPa, and a temperature sensor with a detection range of 0-50 degrees Celsius, making it suitable for mild reaction environments with low concentrations.

[0054] The concentration monitoring module uses an online laser Raman spectrometer with a detection wavelength of 785 nanometers, which is suitable for low-concentration detection and has higher sensitivity. It has a resolution of 0.03 nanometers, and the concentration deviation alarm threshold is set to ±0.01%. Alarm signals are simultaneously pushed to the operation and maintenance mobile terminal.

[0055] The exhaust gas treatment module has an activated carbon adsorption tower with a volume of 30 liters and an activated carbon filling height of 0.8 meters. The hot nitrogen generator has an output temperature of 120 degrees Celsius, a flow rate of 5 cubic meters per hour, a regeneration time of 2 hours, and an ignition temperature of 300 degrees Celsius for the catalytic burner. The combustion products are discharged through an 8-meter exhaust stack.

[0056] The central control module uses a small PLC with 8 analog inputs and 6 analog outputs, an 8-inch touch screen, a newly added low-concentration mixing mode, and automatic optimization of metering accuracy and monitoring frequency.

[0057] II. Control Process and Emergency Stop Test Raw material preparation steps: The pressure of the nitrogen buffer tank in the pressure balancing module is set to 0.3 MPa, and the pressure of the storage tank is stabilized at 0.3 ± 0.01 MPa. The raw material preheating module preheats silane to 5 degrees Celsius to prevent silane liquefaction at low temperatures, and cyclohexane to 15 degrees Celsius. The flow rate of the preheater tubes is controlled at 2 liters per hour to prevent raw materials from stagnating in the tubes.

[0058] Precise metering steps: Total flow rate 5 liters per hour. The theoretical flow rates are calculated based on the target ratio: 0.05 liters per hour for silane, 0.5 liters per hour for nitrogen, and 4.45 liters per hour for cyclohexane. The mass flow meter reports an actual silane flow rate of 0.048 liters per hour, and the concentration monitoring module detects an actual concentration of 0.96%. =1% - 0.96% = 0.04%, =1%, =0.9, substituting into the formula, we get =0.05×(1+0.9×0.04 / 1)=0.05×1.036=0.0518 liters per hour. After adjustment, the silane flow rate increased to 0.0518 liters per hour, and the concentration returned to 1.0% after 3 seconds.

[0059] Emergency shutdown test: The mixing tank was manually heated to 36 degrees Celsius, exceeding the temperature threshold of 35 degrees Celsius. The central control module triggered an emergency shutdown within 0.5 seconds: the tank shut-off valve and metering pump were closed, the mixing tank outlet valve was closed, and the top pressure relief valve was opened. Within 10 seconds, the pressure inside the tank dropped from 0.3 MPa to 0.08 MPa. At the same time, the emergency exhaust channel was activated to introduce 20 liters of residual gas from the tank into the catalytic burner. After combustion, the residual silane in the exhaust gas was 0.3 ppm. The heating fault was eliminated 30 minutes after the shutdown, and the system resumed operation.

[0060] III. Data Representation and Interpretation Table 2 Comparison of key indicators between the conventional system and this system for preparing mixed gas for photovoltaic applications.

[0061] Table 2 shows that in low-concentration scenarios, the traditional system suffers from amplified errors due to the metering pump's low-flow delivery, resulting in a mixing accuracy of only ±0.1%. Offline sampling and detection lead to a concentration response time of up to 10 seconds, and the inability to regenerate activated carbon results in a regeneration efficiency of only 60%. Manual shutdown is required when the mixing tank exceeds temperature and pressure limits. Furthermore, the raw material's dissolution stability is poor at low concentrations, with a concentration drift of 0.2% within 4 hours. This system, by adapting to low-concentration metering pumps and a high-resolution spectrometer, improves the mixing accuracy to ±0.01%, and online monitoring reduces the concentration response time to 2 seconds. The activated carbon regeneration unit utilizes hot nitrogen treatment, achieving a regeneration efficiency of 92% and reducing maintenance costs. An automatic emergency shutdown process with a response time of 0.5 seconds ensures system safety. Stable temperature and pressure control and optimized stirring design result in a concentration drift of only 0.01% within 8 hours, fully meeting the long-term stability requirements of the photovoltaic coating process.

[0062] Reference Figure 3 This figure visually illustrates the difference in mixing accuracy between the traditional system and the system of this invention under different application scenarios. Due to the lack of pressure balancing and metering correction mechanisms, the traditional system's mixing accuracy in all scenarios is above ±0.18%, and even reaches ±0.25% in the LED packaging scenario, failing to meet the demands of high-precision manufacturing. This invention stabilizes the tank pressure through a pressure balancing module and dynamically adjusts the metering flow rate using a mixing accuracy correction formula, controlling the mixing accuracy within ±0.03% in all scenarios, with an optimal ±0.01% in the photovoltaic cell coating scenario. This completely solves the problem of amplified low-concentration mixing errors, adapts to the high-precision preparation needs of multiple scenarios, and provides a stable raw material base for downstream processes.

[0063] Reference Figure 4This figure clearly illustrates the impact of stirring structure and rotation speed on the dissolution time of silane. Traditional single-layer stirring paddles can only create a unidirectional flow field. Even with a rotation speed of 500 r / min, the dissolution time still requires 15 minutes, and the uneven flow field at low rotation speeds leads to a significant increase in dissolution time. The double-layer counter-current stirring paddle of this invention creates an upward and downward convection flow field. Combined with the dispersing effect of the atomizing nozzle, the dissolution time is reduced to 15 minutes at 100 r / min, only 8 minutes at 300 r / min (a common speed in semiconductor processes), and further shortened to 6 minutes at 500 r / min. The marginal effect of increasing rotation speed on optimizing dissolution time is weakened, ensuring dissolution efficiency while avoiding increased energy consumption and equipment wear caused by high rotation speeds.

[0064] Reference Figure 5 This figure reflects the concentration stability of the system during long-term operation. Traditional systems, due to coarse temperature and pressure control and the lack of online concentration correction, exhibit a concentration drift of 0.08% after 2 hours of operation, reaching 0.20% after 4 hours, and drifting to 0.60% after 10 hours, requiring shutdown and recalibration. This invention precisely controls the temperature and pressure of the mixing tank through a PID algorithm, and uses an online laser Raman spectrometer to detect the concentration every 2 seconds. When the deviation exceeds the threshold, the metering flow rate is automatically adjusted. The concentration drift is only 0.01%-0.02% within 8 hours and remains at only 0.02% after 10 hours, eliminating the need for shutdown calibration. This meets the process requirements of photovoltaic coating and other processes that require long-term continuous operation, significantly improving production continuity.

[0065] Reference Figure 6 This figure illustrates the differences in emergency shutdown efficiency under different fault types. Traditional systems lack an automatic emergency shutdown mechanism, requiring manual confirmation and operation for all faults, with a response time of 300 seconds. This can easily lead to the escalation of faults, especially gas leaks, where delayed handling can easily cause safety accidents. The central control module of this invention monitors parameters such as temperature, pressure, flow rate, and concentration in real time. The response time for core faults such as over-temperature and over-pressure is only 0.5 seconds, and faults such as abnormal flow and gas leaks are also controlled within 1.2 seconds. After triggering a shutdown, it automatically cuts off the raw material delivery, depressurizes, and handles residual gas, completely blocking the fault escalation path, significantly reducing safety risks such as silane leaks and tank overpressure, and improving system operational safety.

[0066] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A high-precision proportioning silane mixed gas dissolution mixing system, characterized in that, Includes the following modules: The raw material storage module consists of three independent stainless steel storage tanks, which store silane, dilution gas and solvent respectively. The inner wall of the storage tank is electrochemically passivated. The top is equipped with an inert gas inlet and a pressure monitoring port, the bottom is equipped with a discharge port with a shut-off valve, and the outside is wrapped with a polyurethane insulation layer. The pressure balancing module consists of a 10L nitrogen buffer tank and three pressure regulating valves. The outlet of the buffer tank is connected to the inert gas inlets of the silane, dilution gas, and solvent storage tanks via pipelines. It can regulate the pressure of the three raw material storage tanks to 0.3-0.5MPa, with a pressure deviation of ≤±0.02MPa for each tank. The precision metering module is equipped with one high-precision plunger pump for each of the three storage tanks, and a mass flow meter is connected in series at the outlet of each pump to provide real-time feedback on the delivery flow to the subsequent central control module. The dissolving and mixing module adopts a double-layer jacketed mixing tank with three raw material inlets at the top, atomizing nozzles installed at the inlets, a double-layer inclined blade reverse stirring paddle in the middle, and a mixed gas outlet at the bottom of the tank. The jacket layer can be circulated with a temperature control medium. The temperature and pressure control module includes a temperature control unit and a pressure control unit. The temperature control unit is equipped with an electric regulating valve and a platinum resistance temperature sensor at the inlet of the mixing tank jacket. The pressure control unit is equipped with a pressure sensor and a safety relief valve at the top of the mixing tank. The concentration monitoring module is equipped with an online laser Raman spectrometer at the outlet of the mixing tank. It collects the actual concentration value of silane in the mixed gas every 2 seconds, and the detection data is transmitted to the central control module in real time. The exhaust gas treatment module consists of an activated carbon adsorption tower and a catalytic burner. The adsorption tower is filled with columnar activated carbon, with its inlet connected to the exhaust port of the mixing system and its outlet connected to the catalytic burner. The central control module uses a PLC controller and a touch screen. The PLC has analog input / output and digital input / output functions, and can receive relevant data from each module and output control signals to the corresponding actuators. The central control module incorporates a proportioning accuracy correction process in the precise metering step. When there is a persistent deviation between the actual flow rate and the theoretical flow rate reported by the mass flow meter, a formula is used to correct this. Calculate the corrected metered flow rate, where The corrected raw material flow rate, The theoretical flow rate before correction. The flow correction factor is set to a value of 0.8-1.

2. This refers to the deviation between the actual concentration detected by the concentration monitoring module and the set concentration. This is the set concentration value for the silane mixture.

2. The high-precision proportioning silane mixed gas dissolution mixing system according to claim 1, characterized in that, It also includes a raw material preheating module, which is equipped with a tubular preheater for each of the silane and solvent storage tanks. The raw material flows through the tube side, and hot water is introduced into the shell side as the heating medium. A temperature sensor is installed at the inlet and a flow regulating valve is installed at the outlet. Depending on the type of raw material, the silane is preheated to 5-10℃ and the solvent is preheated to 15-25℃, which reduces the loss of dissolution efficiency caused by the sudden temperature change after the low-temperature raw material enters the mixing tank.

3. The high-precision proportioning silane mixed gas dissolution mixing system according to claim 1, characterized in that, The double-layer inclined blade agitator of the dissolution and mixing module has a special structural design. The diameter of the upper agitator is 1 / 2 of the inner diameter of the mixing tank and the blade tilt angle is 45°. The diameter of the lower agitator is 2 / 3 of the inner diameter of the mixing tank and the blade tilt angle is 60°. The two agitators rotate in opposite directions, with the upper one rotating clockwise and the lower one rotating counterclockwise, which can form an upper and lower convection mixing flow field in the tank.

4. The high-precision proportioning silane mixed gas dissolution mixing system according to claim 1, characterized in that, The concentration monitoring module is also equipped with a concentration deviation alarm unit. When the online laser Raman spectrometer detects that the actual concentration of silane deviates from the set concentration by more than ±0.05%, the alarm unit will issue an audible and visual alarm signal and transmit the deviation signal to the central control module. The central control module will then automatically trigger the metering flow adjustment process.

5. The high-precision proportioning silane mixed gas dissolution mixing system according to claim 1, characterized in that, The activated carbon adsorption tower of the exhaust gas treatment module is equipped with an adsorbent regeneration unit. The regeneration unit consists of a hot nitrogen generator and a flow control valve. When the pressure difference between the inlet and outlet of the adsorption tower exceeds 0.1 MPa, it is determined that the activated carbon has reached the adsorption saturation state. The central control module automatically closes the inlet valve of the adsorption tower, turns on the hot nitrogen generator, and introduces hot nitrogen at a temperature of 120-150℃ to regenerate the activated carbon. The gas containing silane generated during the regeneration process is introduced into the catalytic burner for treatment. After the regeneration is completed, the hot nitrogen is turned off, and the adsorption function is restored after the temperature of the adsorption tower drops to room temperature.

6. The high-precision proportioning silane mixed gas dissolution mixing system according to claim 1, characterized in that, The metering module is also equipped with a dual-pump redundancy unit. Each high-precision plunger pump corresponding to each raw material is connected in parallel with a standby pump. The central control module monitors the operating current and outlet pressure of the main pump in real time. When the main pump current exceeds the rated value by 10% or the outlet pressure fluctuates by more than ±0.02MPa, it automatically switches to the standby pump and triggers the main pump fault alarm signal at the same time.

7. A control method for a high-precision proportioning silane gas dissolution and mixing system according to any one of claims 1-6, utilizing a system comprising a raw material storage module, a precise metering module, a dissolution and mixing module, a temperature and pressure control module, a concentration monitoring module, a tail gas treatment module, and a central control module, characterized in that, Includes the following steps: In the raw material preparation step, the target ratio of silane, dilution gas and solvent is set through the central control module, the pressure balance module is started to regulate the pressure of the three raw material storage tanks to 0.3-0.5MPa, and the raw material preheating module is started at the same time. In the precise metering step, the central control module calculates the theoretical conveying flow rate of each raw material according to the target ratio, sends a control signal to the plunger pump of the precise metering module, starts the main pump to convey the raw materials, and the mass flow meter collects the actual conveying flow rate in real time and feeds it back to the central control module. In the preheating adjustment step, the metered silane and solvent are fed into the tubular preheater of the raw material preheating module. By adjusting the shell-side hot water temperature of the preheater, the silane outlet temperature is maintained at 5-10℃ and the solvent outlet temperature is maintained at 15-25℃. In the dissolution and mixing step, the preheated silane, solvent and dilution gas are sprayed into the tank through the atomizing nozzle at the top of the mixing tank. The double-layer inclined blade stirring paddle is started and the speed is dynamically adjusted according to the solvent viscosity. After the dilution gas is introduced, the speed is adjusted to 200-300 r / min. At the same time, the temperature control unit is started. The concentration monitoring process involves an online laser Raman spectrometer detecting the actual concentration of silane at the outlet of the mixing tank every 2 seconds and transmitting the detection data to the central control module. In the exhaust gas treatment process, a small amount of exhaust gas generated during the mixing process is introduced into the exhaust gas treatment module through a pipeline. The unreacted silane is first adsorbed by the activated carbon adsorption tower. The adsorbed gas then enters the catalytic burner and is heated to completely burn the residual silane. The system cleaning steps are as follows: After the mixing task is completed, close the shut-off valve of the raw material storage tank, stop the metering pump and the stirring motor, start the cleaning process through the central control module, purge the mixing tank with inert gas, then rinse the tank wall with solvent, and then guide the rinsed solvent into the waste liquid collection tank. Finally, purge the tank with inert gas again until it is dry.

8. The control method for a high-precision proportioning silane mixed gas dissolution mixing system according to claim 7, characterized in that, It also includes an emergency shutdown control process. When the temperature and pressure control module detects that the temperature inside the mixing tank exceeds 35°C or the pressure exceeds 0.6MPa, the central control module immediately triggers an emergency shutdown command. First, it closes the bottom shut-off valve and metering pump of the raw material storage tank, then closes the outlet valve of the mixing tank, opens the top pressure relief valve, and at the same time starts the emergency exhaust channel of the exhaust gas treatment module to quickly introduce the residual gas in the tank into the catalytic burner for treatment until the temperature and pressure return to the normal range.

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