Method and device for rapidly and automatically pumping and washing residual miscellaneous gas in vacuum cavity

Abstract

The invention provides a method and device for rapidly and automatically pumping and washing residual miscellaneous gas in a vacuum cavity, and relates to the technical field of vacuum cleaning.The method comprises the steps that gas parameters of clean gas in an inflation pipeline are obtained, and the clean gas in the inflation pipeline is processed according to the gas parameters; filling the treated clean gas into a cavity, and detecting the cavity pressure of the cavity; in response to the condition that the cavity pressure meets a first switching condition, a rough extraction step is started; and starting a fine extraction step in response to the condition that the cavity pressure meets a second switching condition. The residual miscellaneous gas in the vacuum cavity is efficiently removed, meanwhile, the device has the advantages of being high in equipment compatibility, perfect in safety protection, accurate in parameter control and the like, and the device is suitable for multi-scene requirements.

Description

Technical Field

[0001] This invention relates to the field of vacuum cleaning technology, and in particular to a method and apparatus for rapidly and automatically removing residual impurities from a vacuum chamber. Background Technology

[0002] In ultra-high vacuum and high vacuum fields (such as cryogenic chambers and superconducting magnets), the cleanliness of the vacuum chamber is a core prerequisite for ensuring equipment performance, experimental accuracy, and operational stability. Residual impurities, especially highly absorbent gases such as water vapor and organic matter, can lead to a decrease in chamber vacuum, drift in process parameters, and even serious problems such as material corrosion and equipment failure. Therefore, residual impurities must be removed from the chamber using efficient cleaning techniques before use.

[0003] However, existing vacuum chamber cleaning technologies have many limitations and cannot meet the application requirements of high cleanliness and high efficiency. The main problems are as follows:

[0004] Traditional technologies rely on mechanical evacuation or prolonged high-temperature baking (200 to 400°C): mechanical evacuation can only remove free gases and has a weak effect on removing water vapor and organic matter adsorbed on the cavity wall; although high-temperature baking can enhance the desorption of impurities, it needs to last for several hours (usually more than 8 hours), which consumes a lot of energy and is prone to thermal damage to the cavity material, making it unsuitable for precision parts.

[0005] Existing cleaning methods mostly use manual nitrogen rinsing, which lacks precise control over gas flow and temperature as well as a closed-loop feedback mechanism. The randomness of manual operation leads to large fluctuations in cleaning results, with cleanliness differences between batches reaching 1 to 2 orders of magnitude, making it difficult to meet the consistency requirements of high-precision scenarios such as semiconductor manufacturing and precision coating.

[0006] Most cleaning devices require manual intervention in valve opening and closing and pump start / stop, resulting in high operational complexity and a tendency for pressure rebound in the chamber due to switching delays, thus reducing cleaning efficiency. Furthermore, these devices are often designed for specific volume chambers, making them difficult to adapt to small experimental chambers (0.1m²). 3 From industrial-grade equipment (10m) 3 ( ) to meet diverse needs.

[0007] Traditional systems lack intelligent pressure monitoring and protection. When abnormal pressure occurs in the cavity or pipeline (such as over-inflation or malfunction of air extraction), the overpressure can easily lead to cavity deformation, pipeline rupture, or even gas leakage and other safety accidents, posing potential risks to equipment and operators.

[0008] The accuracy of gas temperature, flow rate and vacuum monitoring is low. Temperature fluctuations can reach ±10℃ or more, flow rate deviations exceed 5%, and vacuum monitoring resolution is only 1Pa. This leads to insufficient replacement of impurities and unstable pumping efficiency, which further affects the reliability of the cleaning effect. Summary of the Invention

[0009] Based on the above problems, this invention proposes a method and apparatus for rapid and automatic removal of residual impurities from a vacuum chamber. Through a fully automated process of heating and cleaning gas replacement and a two-stage pumping circulation, it achieves efficient removal of residual impurities from the vacuum chamber. It also has the advantages of strong equipment compatibility, comprehensive safety protection, and precise parameter control, making it suitable for various scenarios.

[0010] In a first aspect, this application provides a method for rapidly and automatically purging residual impurities from a vacuum cavity, comprising:

[0011] Obtain the gas parameters of the clean gas in the inflation pipeline, and process the clean gas in the inflation pipeline according to the gas parameters;

[0012] The treated clean gas is filled into the cavity, and the cavity pressure is measured.

[0013] In response to the cavity pressure meeting the first switching condition, the coarse pumping step is initiated;

[0014] In response to the cavity pressure meeting the second switching condition, the fine extraction step is initiated.

[0015] Preferably, the method further includes:

[0016] In response to the chamber pressure meeting the first switching condition or the second switching condition, the filling of the chamber with the treated clean gas is stopped.

[0017] In response to the vacuum level of the cavity meeting a preset target, the fine pumping step and / or the coarse pumping step are stopped.

[0018] Preferably, the method further includes:

[0019] In response to a evacuation duration greater than or equal to a duration threshold, the fine evacuation step and / or coarse evacuation step are stopped, and the cavity is refilled with treated clean gas.

[0020] Preferably, the pressure signal of the treated clean gas is less than or equal to a first preset pressure;

[0021] The flow rate signal of the processed clean gas is less than or equal to the preset flow rate;

[0022] The preset flow rate Q = 0.3VL / min, where V is the cavity volume.

[0023] Preferably, the gas parameters include a flow rate signal and a temperature signal; the process of processing the clean gas in the inflation pipeline according to the gas parameters includes:

[0024] Based on the cavity volume and the gas parameters, the temperature of the clean gas in the inflation pipeline is adjusted to obtain the processed clean gas, and the temperature of the processed clean gas meets the preset temperature.

[0025] Preferably, the method further includes:

[0026] Detect the concentration of residual impurities in the cavity;

[0027] In response to the residual impurity concentration meeting a preset order of magnitude, the fine extraction step and / or coarse extraction step are stopped;

[0028] And / or,

[0029] In response to the residual impurity gas concentration meeting a preset quantity level, the filling of the cavity with treated clean gas is stopped.

[0030] Secondly, the present invention provides an apparatus for rapidly and automatically purging residual gases from a vacuum chamber, used in any of the methods for rapidly and automatically purging residual gases from a vacuum chamber as described in any embodiment of the present invention, the apparatus comprising:

[0031] An inflation module is used to fill the cavity with clean gas. The inflation module includes an inflation pipeline and a heating component. The input end of the inflation pipeline is connected to a gas source, and the output end of the inflation pipeline is connected to the cavity. The heating component is used to heat the clean gas in the inflation pipeline.

[0032] A gas extraction module is used to extract gas from the cavity. The gas extraction module includes a coarse extraction component and a fine extraction component, both of which are connected to the cavity.

[0033] The control module is used to monitor the gas parameters of the clean gas in the inflation pipeline and trigger the heating component to heat the clean gas according to the gas parameters, so that the treated clean gas is introduced into the cavity to replace the residual impurities in the cavity.

[0034] The cavity pressure is monitored. When the cavity pressure reaches the first switching condition, the coarse extraction component is activated. When the cavity pressure reaches the second switching condition, the coarse extraction component is deactivated and the fine extraction component is activated.

[0035] Preferably, the control module is further configured to:

[0036] When the cavity pressure meets the first switching condition or the second switching condition, the inflation module is turned off.

[0037] When the vacuum level of the chamber pressure meets the preset target, shut down the coarse pumping component and the fine pumping component;

[0038] When the pumping time is greater than or equal to the time threshold, the inflation module is restarted.

[0039] Preferably, the inflation pipeline is equipped with a pressure reducing valve, a flow regulator, a check valve, and a first pneumatic valve;

[0040] The pressure of the clean gas in the inflation pipeline is less than or equal to the first preset pressure.

[0041] The flow rate of the clean gas in the inflation pipeline is less than or equal to the preset flow rate;

[0042] The preset flow rate Q = 0.3VL / min, where V is the cavity volume.

[0043] Preferably, the inflation module further includes a flow monitoring component and a temperature monitoring component.

[0044] The flow monitoring component is used to monitor the gas flow signal in the inflation pipeline and feed it back to the control module;

[0045] The temperature monitoring component is used to monitor the gas temperature signal in the inflation pipeline and feed it back to the control module;

[0046] The control module is also used to dynamically adjust the heating power of the heating component according to the cavity volume and the flow and temperature signals, so that the temperature of the clean gas in the inflation pipeline meets the preset temperature.

[0047] Preferably, the coarse pumping assembly includes a coarse pump and a second pneumatic valve, wherein the coarse pump is connected to the second pneumatic valve, and the second pneumatic valve is connected to the cavity;

[0048] The fine extraction assembly includes a molecular pump group and a third pneumatic valve, wherein the molecular pump group is connected to the third pneumatic valve, and the third pneumatic valve is connected to the cavity.

[0049] Compared with existing technologies, the beneficial effects of this invention include at least the following: improved pumping efficiency through coarse and fine pumping, saving time, protecting the high-vacuum pump, and contributing to achieving higher ultimate vacuum levels. The cyclic process of heated clean gas replacement combined with coarse and fine pumping, compared to traditional methods relying on prolonged high-temperature baking or simple mechanical pumping, more efficiently removes residual impurities such as water vapor and organic matter adsorbed on the chamber walls, significantly shortening cleaning time. Simultaneously, the design of dynamically adjusting heating power reduces unnecessary energy consumption and lowers operating costs. Fully automated control ensures stable cleaning results; the control module automatically triggers heating, switches pumping stages, and restarts the cycle based on signals such as flow rate, temperature, and pressure, eliminating the randomness of traditional manual operation. Precise control of parameters such as gas flow rate and temperature reduces batch-to-batch differences in cleaning results, meeting the consistency requirements of high-precision scenarios. The device adopts a modular design; the gas filling module can be set with a flow rate according to the chamber volume V, and the pumping module adapts to different pumping needs, compatible with various vacuum chambers ranging from small experimental chambers to industrial-grade equipment. Equipped with a one-way valve to prevent gas backflow, and a pressure relief valve to provide safety protection when the chamber pressure exceeds a second preset pressure, these features, combined with pressure monitoring components, form multiple safety interlocks, effectively preventing equipment damage or safety accidents caused by abnormal pressure, and ensuring the safety of equipment and operators. Precise control is achieved for key parameters such as gas temperature, flow rate, and chamber pressure. For example, the heating power is dynamically adjusted to maintain the gas temperature within a preset range, the flow regulator ensures flow accuracy, and the pressure monitoring components and vacuum gauge accurately monitor the pressure, ensuring sufficient replacement of impurities and stable pumping efficiency, thus improving the reliability of the cleaning effect. Attached Figure Description

[0050] Figure 1 This is a schematic diagram of a method for rapidly and automatically purging residual impurities from a vacuum chamber according to an embodiment of the present invention;

[0051] Figure 2 This is a schematic diagram of the module composition of the vacuum chamber rapid automatic purging of residual impurities according to an embodiment of the present invention;

[0052] Figure 3 This is a schematic diagram of the structure of the vacuum chamber rapid automatic purging device for residual impurities according to an embodiment of the present invention;

[0053] Figure 4 This is a schematic diagram of the coarse extraction component structure according to an embodiment of the present invention;

[0054] Figure 5 This is a schematic diagram of the fine extraction component structure according to an embodiment of the present invention;

[0055] In the diagram: 1. Gas source; 2. Pressure reducing valve; 3. Flow regulator; 4. Heating assembly; 5. Flow monitoring assembly; 6. Temperature monitoring assembly; 7. Check valve; 8-1. First pneumatic valve; 8-2. Second pneumatic valve; 8-3. Third pneumatic valve; 9-1. First pressure relief valve; 9-2. Second pressure relief valve; 10. Pressure monitoring assembly; 11. Positive and negative pressure gauges; 12. Coarse pump; 13. Vacuum gauge; 14. Molecular pump assembly; 15. Main valve; 16. Cavity extraction port; 17. Vacuum chamber. Detailed Implementation

[0056] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided to make the invention more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0057] Example 1, refer to Appendix Figure 1 This embodiment provides a method for rapidly and automatically purging residual impurities from a vacuum chamber, including:

[0058] Obtain the gas parameters of the clean gas in the inflation pipeline, and process the clean gas in the inflation pipeline according to the gas parameters.

[0059] The treated clean gas is filled into the cavity, and the cavity pressure is measured; the cavity is a vacuum cavity.

[0060] In response to the chamber pressure meeting the first switching condition, the coarse pumping step is initiated.

[0061] In response to the cavity pressure meeting the second switching condition, the fine extraction step is initiated.

[0062] In one possible implementation, the method further includes:

[0063] In response to the chamber pressure meeting either the first or the second switching condition, the filling of the chamber with treated clean gas is stopped.

[0064] In response to the vacuum level of the cavity meeting a preset target, the fine pumping step and / or the coarse pumping step are stopped.

[0065] In one possible implementation, the method further includes:

[0066] In response to a evacuation duration greater than or equal to a duration threshold, the fine evacuation step and / or coarse evacuation step are stopped, and the cavity is refilled with treated clean gas.

[0067] The working principle of the above technical solution is as follows:

[0068] When clean gas is introduced into the cavity, the gas status is monitored in real time. When a stable flow signal and initial temperature signal are detected, the heating component is triggered to work. The heat energy is used to enhance the ability of the clean gas to replace the residual impurities inside the cavity. The high temperature environment can reduce the adsorption force of impurities on the cavity wall. At the same time, the continuous introduction of clean gas creates a positive pressure environment, which drives the impurities away from the cavity and achieves preliminary purification. The residual gases include organic matter, particulate matter, and trace amounts of water vapor.

[0069] The treated clean gas is filled into the chamber, and the positive pressure is used to push the residual impurities away from the chamber wall. At the same time, the chamber pressure is monitored in real time to provide a basis for switching the extraction stage. When the pressure meets the first switching condition, coarse extraction is started to quickly reduce the pressure. When the second switching condition is met, it is switched to fine extraction to achieve deep purification. The impurity gas extraction and washing is completed through a parameter-driven automated process.

[0070] If the vacuum level of the cavity reaches the preset target, the pumping will automatically stop; if the target is not reached but the cumulative start time of coarse and fine pumping reaches the threshold, it is determined that the residual impurities are affecting the pumping speed, the pumping will automatically stop and the gas pretreatment and inflation process will be restarted to enhance the impurity removal effect through circulation.

[0071] The effects of the above technical solution are as follows:

[0072] Gas pretreatment enhances the ability to replace impurities, and staged gas extraction adapts to the extraction needs of different pressure ranges. Combined with a circulation mechanism triggered by cumulative time, it improves the removal rate of impurities compared to the traditional single extraction and washing method at room temperature, especially for high-boiling-point and strongly adsorbed impurities. The extraction stage is automatically switched by pressure signal, and the dual stop conditions of vacuum degree and time are combined to achieve unmanned operation throughout the process, avoid human operation error, and improve the consistency of extraction and washing effects of different batches.

[0073] The cumulative time threshold prevents unnecessary evacuation time, and the cycle restart mechanism specifically handles stubborn impurities, reducing unnecessary energy consumption (such as heating and pump operation) and clean gas consumption, shortening the overall process time, and improving the cleanliness of the chamber by 1 to 2 orders of magnitude, for example, from 10 -3 Pa level upgraded to 10 -4 Below the Pa level. Through dynamic parameter adjustment (such as gas processing intensity and switching threshold), it can be adapted to different volume chambers and types of impurities, and is suitable for diverse scenarios from small laboratory chambers to industrial-grade equipment.

[0074] For example, in one possible implementation, the first switching condition is typically 10000 Pa.

[0075] In one possible implementation, the second switching condition is 10 Pa.

[0076] In one possible implementation, the target vacuum level is 0.1 Pa.

[0077] In one possible implementation, the cleaning gas is an inert gas.

[0078] In one possible implementation, the cleaning gas is an inert gas, specifically nitrogen or argon.

[0079] In one possible implementation, the pressure signal of the processed clean gas is less than or equal to a first preset pressure.

[0080] The flow rate signal of the processed clean gas is less than or equal to the preset flow rate.

[0081] The preset flow rate Q = 0.3VL / min, where V is the cavity volume.

[0082] In one possible implementation, the first preset pressure can be set to 0.35 MPa.

[0083] The pressure of the treated clean gas is limited to a first preset pressure by a pressure reducing valve to prevent excessive stress on the cavity or pipeline due to excessive gas pressure. This also ensures a stable gas flow, providing a basis for flow rate adjustment. Based on the cavity volume V, the clean gas flow rate is strictly controlled within a preset flow rate Q = 0.3VL / min. The flow rate setting is based on the matching relationship between the cavity volume and the impurity gas replacement requirements, ensuring sufficient gas volume to expel residual impurities from the cavity while avoiding gas waste or a sudden increase in cavity pressure due to excessive flow, making the replacement process of hot gas and impurities more efficient.

[0084] The dual constraints of pressure and flow rate create a safe and efficient balance. Stable pressure provides the premise for precise flow rate adjustment, while flow rate adaptation ensures uniform gas diffusion inside the cavity. Combined with heating treatment, this enhances the removal of impurities, laying a solid foundation for subsequent coarse and fine extraction steps.

[0085] In one possible implementation, the gas parameters include a flow rate signal and a temperature signal; the process of processing the clean gas in the inflation pipeline according to the gas parameters includes:

[0086] Based on the cavity volume and the gas parameters, the temperature of the clean gas in the inflation pipeline is adjusted to obtain the processed clean gas, and the temperature of the processed clean gas meets the preset temperature; for example, the preset temperature is the target temperature of 100℃±2℃.

[0087] In one possible implementation, adjusting the temperature of the clean gas in the inflation pipeline based on the cavity volume and the gas parameters includes:

[0088] The mass flow rate of the gas is determined based on the volume V of the cavity.

[0089] Based on the gas's mass flow rate, specific heat capacity, and target temperature difference, the reference heating power is determined according to the first law of thermodynamics; where the target temperature difference is the difference between the preset target temperature and the initial temperature of the clean gas measured by the heating component.

[0090] The gas flow rate and temperature signal are collected in real time. Based on the degree to which the flow rate deviates from the reference flow rate, a first correction coefficient is generated. When the actual flow rate is higher than the reference flow rate, the heating power is increased by the first correction coefficient. When the actual flow rate is lower than the reference flow rate, the heating power is decreased by the first correction coefficient.

[0091] Based on the degree of deviation between the real-time temperature and the preset temperature, a second correction coefficient is generated. When the real-time temperature is lower than the preset temperature, the heating power is increased by the second correction coefficient, and when the real-time temperature is higher than the preset temperature, the heating power is reduced by the second correction coefficient.

[0092] The reference heating power is coupled with the first correction coefficient and the second correction coefficient to generate real-time heating power and output to the heating component. The dynamic stability of the cavity gas temperature within the preset range is achieved through closed-loop iterative adjustment.

[0093] In one possible implementation, the coupling operation employs a two-factor dynamic weighting algorithm:

[0094] Real-time heating power = reference heating power × (first correction coefficient × a + second correction coefficient × b), where a and b are dynamic weighting coefficients, and a + b = 1; the weight allocation is dynamically adjusted based on deviation priority. When the influence of temperature deviation is higher than that of flow deviation, the weight of b automatically increases (and a decreases accordingly) to prioritize temperature stability; when the influence of flow deviation is higher than that of temperature deviation, the weight of a automatically increases (and b decreases accordingly) to prioritize adapting to flow changes; when the influence of the two deviations is balanced, a and b take equivalent weights; the influence of deviation is calculated in real time by the ratio of the deviation value to the safety threshold of the corresponding parameter; the influence is determined by the ratio of the current deviation value to the maximum allowable deviation value (safety threshold) of the parameter. The higher the ratio, the greater the influence of the deviation on the pumping efficiency or system safety.

[0095] Compared to fixed-power heating or single-parameter adjustment, this system uses a self-learning model to predict the baseline power, employs dynamic compensation with dual correction coefficients, and prioritizes weighted coupling to reduce gas temperature fluctuations and stably control the gas temperature within a preset range (e.g., ±2℃). This effectively prevents a decrease in impurity gas replacement efficiency due to temperature instability. The multi-parameter correlation mechanism can handle sudden flow fluctuations (e.g., unstable gas source pressure) and temperature hysteresis effects (e.g., changes in pipeline heat dissipation), ensuring stable heating even under dynamic disturbances. Dynamic power adjustment avoids overheating and underheating, reducing heating energy consumption. Simultaneously, precise matching of flow and power reduces ineffective gas consumption due to insufficient temperature, improving the utilization rate of clean gas.

[0096] In one possible implementation, the airflow direction along the inflation line is divided into at least two independently temperature-controlled heating zones; the method further includes:

[0097] Based on the real-time flow rate and the real-time temperature, different real-time heating power is allocated to each heating zone.

[0098] Among them, the heating zone located upstream of the airflow focuses on rapidly increasing the gas temperature, and its power allocation weight prioritizes responding to changes in flow rate; the heating zone located at the end of the airflow focuses on accurately stabilizing the gas temperature, and its power allocation weight prioritizes responding to temperature deviations.

[0099] Upstream heating zone (e.g., the first heating zone near the gas source): Taking advantage of its location at the beginning of the airflow, it undertakes the core function of rapid heating. The heating elements in this zone have a high power density, which can quickly absorb heat in the early stage of gas entering the pipeline, shortening the heating time from the initial temperature to near the preset temperature.

[0100] The airflow end heating zone (e.g., the second heating zone near the cavity inlet): As a temperature stabilization fine-tuning section, its heating element power adjustment accuracy is higher. It is mainly used to offset temperature fluctuations caused by factors such as pipeline heat dissipation and airflow disturbance, and to ensure that the gas temperature before entering the cavity is stable within the preset range.

[0101] Based on the real-time collected flow rate and end temperature signals of the inflation pipeline, the real-time heating power is dynamically allocated to the two heating zones:

[0102] Upstream heating zone: Power allocation weights prioritize responses to flow rate changes. When the real-time flow rate increases (the amount of gas flowing per unit time increases), the power share of this zone is automatically increased (e.g., from 60% to 70% of the total power) to match the greater heat demand by enhancing heating intensity; when the flow rate decreases, the power share is reduced to avoid energy waste.

[0103] Terminal heating zone: Power allocation prioritizes response to temperature deviations. When the real-time temperature is lower than the preset temperature, the power proportion of this zone is increased (e.g., from 40% to 50% of the total power) to eliminate the temperature difference through precise heat compensation; when the temperature is higher than the preset temperature, the power proportion is reduced, or even heating is temporarily stopped to achieve slight temperature correction.

[0104] The rapid heating of the upstream heating zone lays the foundation for precise temperature control in the downstream heating zone, while the fine-tuning of the downstream heating zone compensates for potential temperature fluctuations in the upstream heating (such as heating lag caused by sudden changes in flow rate). The two work together through real-time data interaction with the control module, ensuring that the gas reaches the preset temperature and maintains temperature stability (fluctuation range ≤ ±2℃) after flowing through the entire pipeline.

[0105] In one possible implementation, the step of generating the first correction coefficient includes:

[0106] The collected real-time flow signal is subjected to first derivative calculation or trend fitting to predict the flow change trend after a future time Δt. If the flow signal changes relatively smoothly, the first derivative calculation is used to calculate the rate of change of the current flow (such as the increase or decrease of flow per unit time), which directly reflects the instantaneous change trend of the flow. If the flow signal fluctuates, a flow prediction value for a future time Δt (such as 1 to 3 seconds, set according to the thermal response characteristics of the heating component) is generated by sliding window trend fitting (such as linear regression or exponential smoothing) to filter out instantaneous noise and obtain a stable trend.

[0107] Based on this predicted trend, the first correction factor calculated based on the current flow deviation is corrected in advance to offset the temperature hysteresis effect caused by the thermal inertia of the heating component.

[0108] If it is predicted that the flow rate will increase in the future within a time interval Δt (e.g., the trend shows that the flow rate will increase from 20L / min to 30L / min), then the correction magnitude will be further increased based on the first correction factor calculated based on the current flow rate deviation, so as to reserve heating power in advance for the upcoming greater heat demand.

[0109] If the predicted flow rate will decrease (e.g., from 30 L / min to 20 L / min), the current correction factor should be appropriately reduced (e.g., adjusted to 1.0) to avoid overheating due to thermal inertia.

[0110] The corrected first correction factor is applied to the power distribution in the upstream heating zone, synchronizing the adjustment rhythm of the heating power with the trend of flow rate changes. Due to the thermal inertia of the heating components (e.g., a 0.5 to 2-second lag between power change and temperature response), the advance correction by Δt time allows the heating power to be adjusted as the flow rate actually changes, ensuring that the temperature response matches the flow rate change in real time.

[0111] In one possible implementation, the method further includes:

[0112] The concentration of residual impurities in the cavity is detected.

[0113] In response to the residual impurity gas concentration meeting a preset quantity level, the fine extraction step and / or coarse extraction step are stopped; and / or, in response to the residual impurity gas concentration meeting a preset quantity level, the filling of the cavity with treated clean gas is stopped.

[0114] In one possible implementation, the method further includes:

[0115] Obtain performance indicators after each purging cycle; the performance indicators include the final vacuum level, the time to reach the target vacuum level, and / or the residual impurity concentration in the cavity.

[0116] The performance indicators of the current cycle are compared with the preset target values. Based on the comparison results, the process parameters of the inflation step in the next cycle are dynamically adjusted. The process parameters include, but are not limited to, the temperature of the inflated clean gas, the inflation flow rate, and the inflation time.

[0117] If the final residual impurity concentration of the current cycle is higher than the target value, the temperature of the clean gas introduced and / or the charging time will be increased in the next cycle.

[0118] If the time to reach the target vacuum level in the current cycle is longer than expected, increase the inflation flow rate in the next cycle.

[0119] The optimization algorithm includes PID control algorithm, fuzzy logic control, or machine learning model trained based on historical data;

[0120] The magnitude of the process parameter adjustment is proportional to, integral to, or output by the prediction model, the degree to which the performance index deviates from the target value.

[0121] The dynamically adjusted process parameters also include parameters for the evacuation step;

[0122] The parameters include: the switching pressure point between the coarse extraction step and the fine extraction step, and the pumping speed setting of the fine extraction pump.

[0123] The working principle of the above technical solution is as follows:

[0124] After each evacuation, the performance indicators of this evacuation are evaluated. These performance indicators include the final vacuum level, the time to reach the target vacuum level, and / or the residual impurity concentration in the cavity. The residual impurity concentration in the cavity can be measured by a residual gas analyzer. Based on the deviation between the performance indicators and the preset target values, an optimization algorithm (such as PID control, fuzzy logic, or gradient descent method) is used to generate the adjustment amount of the inflation temperature in the next cycle. Through iterative cycles, the parameters such as the inflation temperature are automatically converged to near the optimal value that achieves the best evacuation performance.

[0125] If the final vacuum level does not meet the standard (e.g., measured 1×10⁻⁶), -4 Pa > Target 1×10 -5 If the concentration of gas exceeds the threshold (e.g., Pa) or the residual concentration exceeds the threshold, it is determined that the replacement of impurities is insufficient. The amount of increase in the inflation temperature is calculated by optimizing the algorithm (e.g., from 100℃ to 110℃), while the inflation flow rate is appropriately increased (e.g., from 0.2VL / min to 0.25VL / min), and the inflation time is extended (e.g., from 3 minutes to 4 minutes) to enhance the ability of hot gas to remove impurities from the cavity wall.

[0126] If the time to reach the target is too long (e.g., the actual measurement of 20 minutes > the target of 15 minutes) but the vacuum level meets the target, it is determined that the pumping efficiency is insufficient. The inflation temperature is finely adjusted to a better range through fuzzy logic algorithm (e.g., from 120℃ to 110℃ to avoid overheating and increased gas viscosity), while the ineffective inflation time is shortened (e.g., from 5 minutes to 3 minutes) to reduce the redundancy of cavity pressure before pumping.

[0127] If the performance indicators are better than the target value for three consecutive cycles, the parameters are fine-tuned in the direction of energy saving using the gradient descent method (e.g., the temperature is reduced by 5°C and the flow rate is reduced by 0.02 VL / min) to reduce energy consumption while ensuring the effect.

[0128] Each adjusted process parameter is applied to the next flushing cycle, and the trend of performance indicators is continuously monitored. If parameter adjustments bring the indicators closer to the target value (e.g., vacuum level from 1×10⁻⁶), then... -4 Pa rises to 1×10 -5 If the temperature exceeds the set value (e.g., the residual concentration increases due to excessively high temperature), the parameters are adjusted in the same direction. If a reverse deviation occurs (e.g., the residual concentration increases due to excessively high temperature), the parameters are corrected in the opposite direction. Through 3 to 5 iterations, the parameters automatically converge to the optimal range (e.g., temperature 105±2℃, flow rate 0.23±0.01VL / min), achieving a balance between efficiency and energy consumption.

[0129] In one possible implementation, the evacuation time is the cumulative start-up time of both fine and coarse evacuation, specifically the sum of the running time of the coarse evacuation step from start to stop and the running time of the fine evacuation step from start to stop. For example, if fine evacuation is switched to after 3 minutes of coarse evacuation, and the target vacuum level is not reached after 10 minutes of fine evacuation and the cumulative time (3 + 10 = 13 minutes) reaches the threshold, then evacuation is stopped and the process is restarted. This parameter serves as a supplementary criterion for judging whether the vacuum level meets the standard, preventing indefinite delays in evacuation due to stubborn impurities and ensuring an efficient closed-loop process.

[0130] In one possible implementation, the evacuation time is the fine evacuation time, and the time threshold is determined as follows: initially, a reference time is preset based on the cavity volume, target vacuum degree and pumping speed characteristics of the molecular pump group. Subsequently, after each cycle is completed, the time threshold is dynamically corrected according to the deviation between the actual time taken to achieve the target vacuum degree and the reference time, so that the threshold is adaptively shortened as the cavity cleanliness improves.

[0131] Reference duration = k2 × cavity volume / (molecular pump assembly pumping speed × (initial pressure - target vacuum level)).

[0132] Where k2 is the duration correction coefficient, which is preset based on historical data.

[0133] The quantitative formula for the baseline duration, combined with historical correction coefficients, frees the initial threshold setting from reliance on manual experience and ensures better matching with the cavity volume and improved performance of the extraction equipment. The dynamic correction mechanism allows the threshold to adaptively adjust with changes in cleanliness, reducing ineffective time consumption during the fine extraction stage compared to a fixed duration setting. The combination of formulaic calculation and dynamic correction allows for adaptation to different cavity volumes and molecular pump models without the need for manual recalibration. The introduction of historical correction coefficients reduces the commissioning costs of new cavities or post-maintenance equipment and improves operational stability. When residual impurities cause a decrease in pumping speed, the duration threshold trigger restart can promptly initiate a new round of hot gas replacement. High temperature and airflow disturbance enhance the impurity removal effect. Compared to a single pressure trigger mode, the impurity concentration removal capability is improved by 1 to 2 orders of magnitude, especially for high-boiling-point and highly adsorbent impurities.

[0134] In one possible implementation, the cavity is depressurized in response to the cavity pressure being greater than a second preset pressure, wherein the second preset pressure is the product of the cavity working pressure and a preset coefficient, and the preset coefficient is a constant greater than 1 and less than 2, for example, a preset coefficient of 1.1.

[0135] In one possible implementation, the method for determining and updating the cavity working pressure includes:

[0136] S1: Based on the application scenarios and rinsing process requirements of the vacuum chamber, the pressure setpoints of key nodes in the rinsing process are selected as candidate values ​​for the chamber's working pressure; the key nodes include at least one of the following:

[0137] The pressure point of switching between the coarse extraction stage and the fine extraction stage.

[0138] After the target vacuum level is reached during the fine pumping stage, the system enters a stable pressure setpoint for pressure maintenance.

[0139] S2: Set the safety margin value δ, which is a fixed percentage or fixed differential pressure value of the maximum safe pressure resistance value of the cavity.

[0140] If the candidate working pressure value is within the rated working pressure range of the air extraction equipment, and satisfies the condition that the candidate working pressure value is ≤ (maximum safe pressure value - δ), then the candidate value is determined as the current working pressure of the cavity.

[0141] If any of the above conditions are not met, an alarm signal will be generated and a prompt will be made to adjust the rinsing process parameters, and then the candidate values ​​will be re-determined.

[0142] S3: After the system is first started or the cavity is maintained, a trial pumping and washing process is executed, and the average stable pressure value recorded after the fine pumping stage is set as the initial cavity working pressure. In subsequent automatic pumping and washing cycles, the stable pressure value after the fine pumping of each cycle is continuously monitored. If the standard deviation of the fluctuation of this value is less than or equal to the preset deviation threshold in N consecutive cycles (N≥3), the cavity working pressure is automatically updated to the arithmetic mean of the stable pressure values ​​of the most recent M cycles (M≥5).

[0143] The effects of the above technical solution are as follows:

[0144] The pressure setpoints at key nodes in the vacuuming process (such as the pressure switching between coarse and fine vacuuming, and the pressure maintaining the target vacuum level) are used as candidate values, directly linking them to the core requirements of the vacuuming process to ensure that the working pressure matches the functional positioning of the actual vacuuming stage. The initial working pressure is determined through trial vacuuming and dynamically updated based on stable pressure values ​​from multiple cycles, making the working pressure more closely match the actual operating state of the chamber and avoiding deviations between theoretical settings and actual working conditions. A safety margin value δ (based on the maximum safe withstand pressure value) is introduced. By constraining the candidate working pressure value to be ≤ maximum safe withstand pressure value - δ, sufficient safety buffer space is reserved for the chamber to prevent pressure fluctuations from exceeding the safety threshold. Simultaneously, an alarm is triggered when the candidate value does not meet the equipment's rated range or safety conditions, promptly mitigating risks such as equipment overload and chamber damage caused by improper pressure settings, thus improving the safety of system operation.

[0145] Differentiated working pressure determination strategies are adopted for different stages, such as initial startup, maintenance, or long-term operation: during the trial cleaning stage, an initial benchmark is quickly established, and stability is verified by continuous N cycles of fluctuation monitoring. The working pressure is then updated with the average value of M cycles. This ensures the timeliness of the pressure setting (adapting to stable pressure changes after the improvement of cavity cleanliness) and reduces the impact of single fluctuations through statistical averaging, so that the working pressure is always in a stable and reliable range.

[0146] The second preset pressure (working pressure × 1.1 and other preset coefficients) is calculated based on the determined working pressure to closely link the pressure relief trigger threshold with the actual working state of the cavity. This ensures that the protection will not be delayed due to an excessively high threshold, nor will it be falsely triggered due to an excessively low threshold. This ensures that the pressure relief protection will only be activated when a real overpressure risk occurs, taking into account both safety and the continuity of the pumping process.

[0147] In one possible implementation, the method further includes:

[0148] Establish a standard curve library containing multiple standard pressure-time curves associated with different pumping load levels; wherein each standard curve is the average value of multiple successful pumping cycles at the corresponding load level.

[0149] Based on the residual gas concentration of the previous cycle, the type of preceding process in the cavity, or the duration of the cavity's exposure to the atmosphere, the pumping load level for this cycle is estimated, and a matching standard pressure-time curve is selected from the standard curve library as the expected standard curve for this cycle.

[0150] During the coarse or fine extraction process, pressure data is collected in real time to generate the current pressure-time curve;

[0151] Calculate the deviation of the current curve from the expected standard curve using at least one of the following methods:

[0152] At several preset key pressure points, calculate the ratio of the time required for the current curve to reach each pressure point to the time required for the expected standard curve to reach the same pressure point.

[0153] Within a preset specific pressure range, calculate the ratio of the average pumping speed of the current curve to the average pumping speed of the expected standard curve within the same pressure range.

[0154] The calculated ratio is compared with a preset tolerance threshold to quantify the degree of deviation.

[0155] In response to any ratio exceeding its corresponding tolerance threshold, the system automatically determines that the current rinsing cycle is abnormal and executes a process termination operation.

[0156] The tolerance threshold is a confidence interval obtained through statistical methods based on historical successful rinsing cycles; and the width of the tolerance threshold interval is positively correlated with the cumulative working time of the rinsing equipment to accommodate the natural degradation of its performance.

[0157] The standard curve library establishes dedicated benchmarks for different pumping load levels, avoiding the inadequacy of traditional single-threshold detection in adapting to complex operating conditions. For example, for loads with high residual gas concentrations (preceding processes involving volatile materials), the pressure drop rate of the standard curve should be slower. If a low-load standard is used for judgment, it will be misjudged as abnormal. However, the solution makes the benchmark more realistic by matching the load level, reducing the false positive rate of abnormality.

[0158] By collecting pressure data in real time and comparing it with the expected standard curve (e.g., the time ratio of key pressure points, the pumping speed ratio of a specific range), anomalies can be detected during the pumping process (rather than after it ends). For example, if the current curve takes 30% longer to reach 10 kPa than the standard curve and exceeds the tolerance threshold during the roughing stage, the anomaly is immediately identified and the process is stopped to avoid wasting time and energy due to continued ineffective pumping.

[0159] Timely termination of abnormal circulation prevents substandard chambers from entering subsequent processes, reducing product defects caused by residual impurities. Meanwhile, tolerance thresholds based on historical success data ensure the objectivity of the judgment criteria, keeping the fluctuation range of rinsing quality across different batches and operating conditions within ±5%.

[0160] The tolerance threshold range increases dynamically with the cumulative working time of the pumping equipment (for example, after the pump set has been used for 1000 hours, the tolerance is widened from ±15% to ±20%), which can adapt to the natural performance degradation of the equipment due to wear and aging, avoid misjudging normal degradation as abnormal faults, extend the effective service life of the equipment, and reduce the cost of replacing the equipment prematurely.

[0161] Continuous deviation analysis of the curve can indirectly reflect the equipment status: for example, if the pumping rate ratio during the fine pumping stage remains close to the upper tolerance limit, it may indicate a decline in molecular pump performance or pipeline leakage. Maintenance tips can be generated based on the deviation trend (such as suggesting cleaning the roughing pump filter element or checking pipeline seals), transforming reactive fault repair into proactive preventative maintenance and reducing unplanned downtime.

[0162] Example 2, refer to Appendix Figures 2 to 5 This embodiment provides an apparatus for rapidly and automatically purging residual gases from a vacuum chamber, used in conjunction with the method for rapidly and automatically purging residual gases from a vacuum chamber as described in the embodiments of this application. The apparatus includes:

[0163] An inflation module is used to fill the cavity with clean gas. The inflation module includes an inflation pipeline and a heating component. The input end of the inflation pipeline is connected to a gas source, and the output end of the inflation pipeline is connected to the cavity. The heating component is used to heat the clean gas in the inflation pipeline.

[0164] A gas extraction module is used to extract gas from the cavity. The gas extraction module includes a coarse extraction component and a fine extraction component, both of which are connected to the cavity.

[0165] The control module is used to monitor the gas parameters of the clean gas in the inflation pipeline and trigger the heating component to heat the clean gas according to the gas parameters, so that the treated clean gas is introduced into the cavity to replace the residual impurities in the cavity.

[0166] The cavity pressure is monitored. When the cavity pressure reaches the first switching condition, the coarse extraction component is activated. When the cavity pressure reaches the second switching condition, the coarse extraction component is deactivated and the fine extraction component is activated.

[0167] In one possible implementation, the control module is further configured to:

[0168] When the cavity pressure meets the first switching condition or the second switching condition, the inflation module is turned off.

[0169] When the vacuum level of the chamber pressure meets the preset target, the coarse pumping component and the fine pumping component are shut down.

[0170] When the pumping time is greater than or equal to the time threshold, the inflation module is restarted.

[0171] The working principle of the above technical solution is as follows:

[0172] The gas source delivers clean gas to the cavity through the inflation pipeline. The gas source at the pipeline input provides the initial gas, which is then transmitted to the output end (connected to the cavity) through the pipeline. The heating component is integrated into the inflation pipeline and heats the gas during the gas transmission process. The heating is triggered by the control module based on the gas parameters (such as flow rate and temperature) in the inflation pipeline, ensuring that the gas is introduced into the cavity after reaching the preset temperature, thereby enhancing the ability to remove impurities adsorbed on the cavity wall.

[0173] The extraction module completes gas discharge through a staged collaboration of coarse and fine extraction:

[0174] The coarse extraction component is connected to the cavity. When the control module detects that the cavity pressure has reached the first switching condition, it is activated to quickly extract a large amount of mixed gas from the cavity and reduce the cavity pressure to the end of the coarse extraction.

[0175] The fine evacuation component is also connected to the cavity. When the cavity pressure drops to the second switching condition, the control module shuts down the coarse evacuation component and starts the fine evacuation component to perform deep evacuation of the cavity, further removing trace amounts of residual impurities until the target vacuum level is approached.

[0176] The control module, as the core of the system, enables automated coordination of the entire process, including:

[0177] The parameters of the clean gas in the inflation pipeline are monitored in real time, and the heating components are dynamically triggered to adjust their power to ensure that the gas is introduced into the cavity at the set temperature, thereby improving the efficiency of impurity gas replacement. The cavity pressure is continuously monitored, and the timing of the gas extraction stage is determined by the pressure signal. The start and stop of the coarse extraction component and the fine extraction component are precisely controlled to achieve seamless connection between inflation replacement, coarse extraction, and fine extraction. Through the above closed-loop control, the clean gas replacement and staged gas extraction form a synergistic effect, gradually reducing the concentration of residual impurities in the cavity until the preset cleanliness requirements are met.

[0178] The effects of the above technical solution are as follows:

[0179] The combination of hot gas replacement and two-stage extraction significantly improves the removal rate of impurities compared to traditional room-temperature purging methods, especially for high-boiling-point and highly absorbent impurities. The circulation mechanism can specifically address stubborn residual impurities, improving the cleanliness of the chamber by one to two orders of magnitude, for example, from 10... -3 Pa level upgraded to 10 -4 Below Pa level; heating, evacuation switching, and cycle restart are triggered by sensor signals, enabling unattended operation and reducing labor costs. The number of cycles can be dynamically adjusted according to the concentration of impurities, meeting the stringent cleanliness requirements of high-precision experimental equipment and suitable for rapid purification scenarios in industrial production. Heating and evacuation processes are triggered on demand, avoiding idling. The modular design makes equipment maintenance more convenient; individual components (such as valves or sensors) can be replaced independently without affecting the overall system operation.

[0180] For example, in one possible implementation, the first switching condition is typically 10000 Pa.

[0181] In one possible implementation, the second switching condition is 10 Pa.

[0182] In one possible implementation, the target vacuum level is 0.1 Pa.

[0183] In one possible implementation, the inflation pipeline is provided with a pressure reducing valve 2, a flow regulator 3, a one-way valve 7, and a first pneumatic valve 8-1; the air source 1 is sequentially connected to the pressure reducing valve 2, the flow regulator 3, the heating component 4, the one-way valve 7, and the first pneumatic valve 8-1.

[0184] The gas source is an inert gas cylinder, and the inert gas is nitrogen or argon.

[0185] The pressure reducing valve is used to control the gas pressure to be less than or equal to a first preset pressure; wherein, the first preset pressure can be set to 0.35 MPa.

[0186] The flow regulator is used to control the gas flow rate in the inflation pipeline to be less than or equal to a preset flow rate, wherein the preset flow rate Q = 0.3VL / min, and V is the cavity volume.

[0187] The heating component 4 is used to heat the clean gas.

[0188] The one-way valve 7 is installed in the inflation pipeline to prevent gas backflow.

[0189] The first pneumatic valve 8-1 is a normally closed valve, used to control the connection between the inflation module and the vacuum chamber 17.

[0190] In one possible implementation, the inflation module further includes a flow monitoring component 5 and a temperature monitoring component 6.

[0191] The flow monitoring component 5 has a communication interface for monitoring the gas flow signal in the inflation pipeline and feeding it back to the control module; the flow monitoring component 5 can be a flow transmitter.

[0192] The temperature monitoring component 6 has a communication interface for monitoring the gas temperature signal in the inflation pipeline and feeding it back to the control module.

[0193] The control module is also used to dynamically adjust the heating power of the heating component according to the cavity volume and the flow and temperature signals, so that the temperature of the clean gas in the inflation pipeline meets the preset temperature.

[0194] In one possible implementation, the heating component 4 is a shell-and-tube gas heater, which works in conjunction with the temperature monitoring component 6 to heat the clean gas; the temperature control range of the shell-and-tube gas heater 4 is ≤200℃; the temperature monitoring component can be a temperature transmitter or a sensor.

[0195] In one possible implementation, dynamically adjusting the heating power of the heating component based on the cavity volume and the flow and temperature signals includes:

[0196] The mass flow rate of the gas is determined based on the volume V of the cavity.

[0197] Based on the gas's mass flow rate, specific heat capacity, and target temperature difference, the reference heating power is determined according to the first law of thermodynamics. The target temperature difference is the difference between the preset target temperature and the initial temperature of the clean gas measured by the heating element.

[0198] The gas flow rate and temperature signals are acquired in real time. Based on the degree to which the flow rate deviates from the reference flow rate, a first correction coefficient is generated. When the actual flow rate is higher than the reference flow rate, the heating power is increased by the first correction coefficient. When the actual flow rate is lower than the reference flow rate, the heating power is decreased by the first correction coefficient.

[0199] Based on the deviation between the real-time temperature and the preset temperature, a second correction coefficient is generated. When the real-time temperature is lower than the preset temperature, the heating power is increased through the second correction coefficient. When the real-time temperature is higher than the preset temperature, the heating power is reduced through the second correction coefficient.

[0200] The reference heating power is coupled with the first correction coefficient and the second correction coefficient to generate real-time heating power and output to the heating component. The gas temperature is dynamically stabilized within the preset range through closed-loop iterative adjustment.

[0201] In one possible implementation, the coupling operation employs a two-factor dynamic weighting algorithm:

[0202] Real-time heating power = reference heating power × (first correction coefficient × a + second correction coefficient × b), where a and b are dynamic weighting coefficients, and a + b = 1; the weighting is dynamically adjusted based on deviation priority—when the influence of temperature deviation is higher than that of flow deviation, the weight of b automatically increases (a decreases accordingly) to prioritize temperature stability; when the influence of flow deviation is higher than that of temperature deviation, the weight of a automatically increases (b decreases accordingly) to prioritize adapting to flow changes; when the influence of the two deviations is balanced, a and b take equivalent weights; the influence of the deviation is calculated in real time by the ratio of the deviation value to the safety threshold of the corresponding parameter.

[0203] In one possible implementation, the airflow direction along the inflation line is divided into at least two independently temperature-controlled heating zones; the control module is further configured to:

[0204] Based on the real-time flow rate and the real-time temperature, different real-time heating power is allocated to each heating zone.

[0205] Among them, the heating zone located upstream of the airflow focuses on rapidly increasing the gas temperature, and its power allocation weight prioritizes responding to changes in flow rate; the heating zone located at the end of the airflow focuses on accurately stabilizing the gas temperature, and its power allocation weight prioritizes responding to temperature deviations.

[0206] In one possible implementation, the step of generating the first correction coefficient includes:

[0207] The first derivative of the collected real-time flow signal is calculated or a trend is fitted to predict the flow change trend after a future time interval Δt.

[0208] Based on this predicted trend, the first correction factor calculated based on the current flow deviation is advanced to offset the temperature hysteresis effect caused by the thermal inertia of the heating component.

[0209] In one possible implementation, the control module is further configured to:

[0210] In response to the residual impurity gas concentration meeting a preset quantity level, the fine extraction step and / or coarse extraction step are stopped; and / or, in response to the residual impurity gas concentration meeting a preset quantity level, the filling of the cavity with treated clean gas is stopped.

[0211] In one possible implementation, the control module is further configured to:

[0212] Obtain performance indicators after each purging cycle; the performance indicators include the final vacuum level, the time to reach the target vacuum level, and / or the residual impurity concentration in the cavity.

[0213] The performance indicators of the current cycle are compared with the preset target values. Based on the comparison results, the process parameters of the inflation step in the next cycle are dynamically adjusted. The process parameters include, but are not limited to, the temperature of the inflated clean gas, the inflation flow rate, and the inflation time.

[0214] If the final residual impurity concentration of the current cycle is higher than the target value, the temperature of the clean gas introduced and / or the charging time will be increased in the next cycle.

[0215] If the time to reach the target vacuum level in the current cycle is longer than expected, increase the inflation flow rate in the next cycle.

[0216] The optimization algorithm includes PID control algorithm, fuzzy logic control, or machine learning model trained based on historical data;

[0217] The magnitude of the process parameter adjustment is proportional to, integral to, or output by the prediction model, the degree to which the performance index deviates from the target value.

[0218] The dynamically adjusted process parameters also include parameters for the evacuation step;

[0219] The parameters include: the switching pressure point between the coarse pumping step and the fine pumping step, and the pumping speed setting of the fine pumping pump.

[0220] In one possible implementation, the evacuation time is the cumulative start-up time of both fine and coarse evacuation, specifically the sum of the running time of the coarse evacuation step from start to stop and the running time of the fine evacuation step from start to stop. For example, if fine evacuation is switched to after 3 minutes of coarse evacuation, and the target vacuum level is not reached after 10 minutes of fine evacuation and the cumulative time (3 + 10 = 13 minutes) reaches the threshold, then evacuation is stopped and the process is restarted. This parameter serves as a supplementary criterion for judging whether the vacuum level meets the standard, preventing indefinite delays in evacuation due to stubborn impurities and ensuring an efficient closed-loop process.

[0221] In one possible implementation, the time threshold is the fine pumping time, which is determined as follows: initially, a reference time is preset based on the cavity volume, target vacuum degree and pumping speed characteristics of the molecular pump group. Subsequently, after each cycle is completed, the time threshold is dynamically corrected according to the deviation between the actual time taken to reach the target vacuum degree and the reference time, so that the time threshold is adaptively shortened as the cleanliness of the cavity increases.

[0222] Reference duration = k2 × cavity volume / (molecular pump assembly pumping speed × (initial pressure - target vacuum level));

[0223] Where k2 is the duration correction coefficient, which is preset based on historical data.

[0224] In one possible implementation, the control module is further configured to:

[0225] Establish a standard curve library containing multiple standard pressure-time curves associated with different pumping load levels; wherein each standard curve is the average value of multiple successful pumping cycles at the corresponding load level.

[0226] Based on the residual gas concentration of the previous cycle, the type of preceding process in the cavity, or the duration of the cavity's exposure to the atmosphere, the pumping load level for this cycle is estimated, and a matching standard pressure-time curve is selected from the standard curve library as the expected standard curve for this cycle.

[0227] During the coarse or fine extraction process, pressure data is collected in real time to generate the current pressure-time curve;

[0228] Calculate the deviation of the current curve from the expected standard curve using at least one of the following methods:

[0229] At several preset key pressure points, calculate the ratio of the time required for the current curve to reach each pressure point to the time required for the expected standard curve to reach the same pressure point.

[0230] Within a preset specific pressure range, calculate the ratio of the average pumping speed of the current curve to the average pumping speed of the expected standard curve within the same pressure range.

[0231] The calculated ratio is compared with a preset tolerance threshold to quantify the degree of deviation.

[0232] In response to any ratio exceeding its corresponding tolerance threshold, the system automatically determines that the current rinsing cycle is abnormal and executes a process termination operation.

[0233] The tolerance threshold is a confidence interval obtained through statistical methods based on historical successful rinsing cycles; and the width of the tolerance threshold interval is positively correlated with the cumulative working time of the rinsing equipment to accommodate the natural degradation of its performance.

[0234] In one possible implementation, the air extraction module includes a coarse extraction component and a fine extraction component; the switching between coarse and fine extraction is automatically controlled by a pneumatic valve.

[0235] See attached document Figure 4 The coarse pumping assembly includes a coarse pump 12 and a second pneumatic valve 8-2. The coarse pump 12 is connected to the second pneumatic valve 8-2, and the second pneumatic valve is connected to the vacuum chamber 17.

[0236] The second pneumatic valve 8-2 is a normally closed valve used to control the connection between the roughing assembly and the vacuum chamber. The roughing pump 12 is used to perform roughing on the vacuum chamber. The roughing pump 12 is an oil-free pump, such as a vortex dry pump.

[0237] See attached document Figure 5 The precision pumping assembly includes a molecular pump group 14 and a third pneumatic valve 8-3. The molecular pump group 14 is connected to the third pneumatic valve 8-3, and the third pneumatic valve is connected to the vacuum chamber 17.

[0238] The third pneumatic valve 8-3 is a normally closed valve used to control the connection between the fine pumping assembly and the vacuum chamber 17. The molecular pump assembly 14 is used to perform fine pumping on the vacuum chamber 17.

[0239] In one possible implementation, the pumping module further includes a monitoring unit, which includes a pressure monitoring component 10 and a vacuum gauge 13. The pressure monitoring component is used to monitor the cavity pressure during the coarse pumping process; the vacuum gauge 13 is a high vacuum gauge used to monitor the cavity pressure during the fine pumping process, wherein the pressure monitoring component can be a thin-film capacitor gauge.

[0240] In one possible implementation, the control module has a safety interlock unit.

[0241] The safety interlock unit includes a pressure relief valve, which provides safety protection for the cavity and downstream equipment in the pipeline. When the cavity pressure is greater than or equal to the second preset pressure, the pressure relief valve provides safety protection for the cavity.

[0242] The second preset pressure of the cavity is the product of the cavity working pressure and the preset coefficient. The preset coefficient is a constant greater than 1 and less than 2, for example, the preset coefficient is 1.1.

[0243] The pressure relief valve includes a first pressure relief valve 9-1 and a second pressure relief valve 9-2; the first pressure relief valve 9-1 is used to achieve the safety protection of the pipeline, and the first pressure relief valve 9-1 is selected with a rated discharge value that matches the pipeline; the second pressure relief valve 9-2 is used to achieve the safety protection of the cavity, and the second pressure relief valve 9-2 is selected with a rated discharge value that matches the vacuum cavity 17.

[0244] In one possible implementation, the method for determining and updating the cavity working pressure includes:

[0245] S1: Based on the application scenarios and rinsing process requirements of the vacuum chamber, the pressure setpoints of key nodes in the rinsing process are selected as candidate values ​​for the chamber's working pressure. The key nodes include at least one of the following:

[0246] The pressure point of switching between the coarse extraction stage and the fine extraction stage.

[0247] After the target vacuum level is reached during the fine pumping stage, the system enters a stable pressure setpoint for pressure maintenance.

[0248] S2: Set the safety margin value δ, which is a fixed percentage or fixed differential pressure value of the maximum safe pressure resistance value of the cavity.

[0249] If the candidate working pressure value is within the rated working pressure range of the air extraction equipment, and satisfies the condition that the candidate working pressure value is ≤ (maximum safe pressure value - δ), then the candidate value is determined as the current working pressure of the cavity.

[0250] If any of the above conditions are not met, an alarm signal will be generated and a prompt will be made to adjust the washing process parameters, and then a new candidate value will be determined.

[0251] S3: After the system is first started or the cavity is maintained, a trial pumping and washing process is executed, and the average stable pressure value recorded after the fine pumping stage is set as the initial cavity working pressure. In subsequent automatic pumping and washing cycles, the stable pressure value after the fine pumping of each cycle is continuously monitored. If the standard deviation of the fluctuation of this value is less than or equal to the preset deviation threshold in N consecutive cycles (N≥3), the cavity working pressure is automatically updated to the arithmetic mean of the stable pressure values ​​of the most recent M cycles (M≥5).

[0252] In one possible implementation, the vacuum chamber is leak-tested before the inflation module is executed to ensure a leak rate < 1.0E-7 Pa·m. 3 / s.

[0253] Based on the phased requirement for improved vacuum levels, a combination of oil-free coarse pumping and molecular pump assembly for fine pumping is adopted:

[0254] The coarse pumping stage utilizes the high pumping speed of the coarse pump (oil-free pump, such as a vortex dry pump) to quickly reduce the chamber pressure from atmospheric pressure to the coarse pumping endpoint pressure (e.g., ≤10kPa), efficiently expelling a large amount of residual gas inside the chamber (including the replaced impurities and some clean gas), laying the foundation for subsequent fine pumping.

[0255] When the chamber pressure reaches the preset switching threshold (e.g., ≤10Pa), the coarse pumping passage is automatically closed and the fine pumping passage is opened through the pneumatic valve. By utilizing the adaptability of the molecular pump group to the high vacuum environment, the pressure is further reduced to the target vacuum level (e.g., ≤0.1Pa) to thoroughly remove trace amounts of residual gas inside the chamber.

[0256] By relying on pressure sensors to monitor the chamber pressure in real time, the control system automatically triggers the pneumatic valve when the pressure reaches the corresponding switching condition, achieving seamless switching between coarse and fine pumping without manual intervention.

[0257] A second preset pressure is set based on the pressure resistance limit of the cavity and pipeline. The cavity pressure is monitored in real time by a pressure sensor. When the pressure exceeds the second preset pressure (e.g., due to excessive gas filling or malfunction of the pumping equipment causing abnormal pressure rise), the pressure relief valve is immediately triggered. The cavity pressure relief valve and the pipeline pressure relief valve open respectively to quickly release the overpressure gas in the cavity and pipeline until the pressure drops to a safe range and then automatically closes. This forms a closed-loop protection system of pressure monitoring, anomaly judgment, and pressure relief execution, preventing overpressure from damaging the cavity structure, pump unit, and pipeline.

[0258] Before starting the circulation process, the vacuum chamber is tested for leak resistance using high-precision detection methods such as helium mass spectrometry to ensure a leak rate of <1.0E-7 Pa·m. 3 The principle is to fill the cavity with helium as a tracer gas. If there is a leak in the cavity, the helium will overflow through the leak point and be captured by the leak detector and the leak rate will be quantified. This will help to eliminate problems such as reduced pumping efficiency or substandard vacuum caused by poor sealing in advance, and provide a reliable basis for the subsequent pumping and rinsing process.

[0259] The effects of the above technical solution are as follows:

[0260] Oil-free coarse evacuation can significantly reduce chamber pressure in a short time, improving initial evacuation efficiency compared to single-stage evacuation equipment. Molecular pump-based fine evacuation can precisely break through high vacuum thresholds, increasing the final vacuum level compliance rate and meeting the requirements of high-precision vacuum environments. The application of oil-free coarse evacuation pumps reduces oil vapor contamination from oil pumps, and independent control of the dual-stage evacuation equipment reduces the impact of single-device failures on the overall process. Automatic switching of pneumatic valves avoids delays and errors from manual operation, shortening the transition time from coarse to fine evacuation to the second level and reducing pressure rebound issues caused by switching gaps. Pressure staged control prevents stress damage to the chamber due to sudden pressure changes, and with safety interlocking devices such as pressure relief valves, it effectively prevents overpressure risks. Separate pressure relief valves are installed for the chamber and pipelines, allowing for differentiated pressure relief rates based on their pressure resistance characteristics, ensuring safety while reducing unnecessary gas emissions.

[0261] In one possible implementation, the device further includes a main control valve 15, which is a main valve for the cavity extraction port and is in an open state throughout the entire circulation process.

[0262] In one possible implementation, the device further includes a positive and negative pressure gauge 11, which is used in conjunction with the pressure monitoring component 10 to ensure that the values ​​are not offset; the positive and negative pressure gauge 11 is mostly a mechanical gauge.

[0263] See attached document Figure 3 For example, the specific process of implementing the method for rapidly and automatically purging residual gases from a vacuum cavity as described in this application embodiment is as follows:

[0264] In the initial state, the first pneumatic valve 8-1, the second pneumatic valve 8-2, and the third pneumatic valve 8-3 in the device are all normally closed valves. Throughout the process, the main control valve 15 is in the open state.

[0265] Pressure reducing valve 2 is set to a pressure value ≤ 2 barg, flow regulator 3 is set to a flow rate value < 30 L / m (based on the volume of vacuum chamber 11), and gas source 1 is in the open state; throughout the process, gas source 1, pressure reducing valve 2, and flow regulator 3 are all in the open state.

[0266] The inflation process is as follows: The control module first opens the first pneumatic valve 8-1 and closes the second and third pneumatic valves 8-2 and 8-3, allowing room-temperature high-purity nitrogen or argon to flow into the vacuum chamber 17. After the flow monitoring component 5 detects the gas flow rate and the temperature monitoring component 6 detects the gas temperature, both signals are fed back to the control system. The control system responds, and the shell-and-tube gas heater 4 begins heating and controlling the temperature of the high-purity nitrogen or argon (e.g., to 100°C). This ensures that a certain flow rate of hot nitrogen or argon is injected into the vacuum chamber 17. The one-way valve 7 prevents backflow of gas in the pipeline during this process.

[0267] The evacuation process includes a rough evacuation stage and a fine evacuation stage:

[0268] Coarse pumping stage: When the pressure value of the vacuum chamber 17 reaches the expected value (e.g., expected value ≤ 1 atmosphere, usually 10000Pa), the pressure monitoring component 10 feeds back to the control module. The control module responds by closing the first pneumatic valve 8-1, opening the second pneumatic valve 8-2, and keeping the third pneumatic valve 8-3 closed. The control module starts the vortex dry pump 12. At this time, the flow monitoring component 5 and the temperature monitoring component 6 feed back signals. The control module controls the heating component 4 to stop working, or can maintain the heater at the set temperature to reduce the heating time of the next inflation process. The pressure monitoring component is a vacuum pressure transmitter or sensor, which can usually be a thin-film capacitance gauge.

[0269] Fine pumping stage: During this process, the first pneumatic valve 8-1 remains closed; when the vacuum level of the vacuum chamber 17 approaches (the difference threshold from the limit value is less than the preset value) or reaches the limit value of the vortex dry pump 12 (e.g., the limit value ≤ 10 Pa), the pressure monitoring component 10 feeds back to the control module, and the control module executes to close the second pneumatic valve 8-2 and open the third pneumatic valve 8-3; at this time, the vortex dry pump 12 can be closed or kept running; the molecular pump group 14 is controlled to perform fine pumping.

[0270] When the vacuum gauge 13 detects that the vacuum value has reached the set vacuum value (generally ≤0.1 Pa), or when the running time of the molecular pump group 14 exceeds the time threshold, a feedback signal is sent to the control module. The control module closes the third pneumatic valve 8-3 and simultaneously opens the first pneumatic valve 8-1. At this time, the molecular pump group may or may not close, and the second vacuum pneumatic valve 8-2 is in the closed state. Hot nitrogen or argon gas is then rapidly injected into the vacuum chamber 17 again. This process is repeated to achieve the function of automatically and rapidly purging residual impurities from the vacuum chamber.

[0271] In the event of an abnormal power outage, the first pneumatic valve 8-1, the second pneumatic valve 8-2, and the third pneumatic valve 8-3 will all automatically close (normally closed valves) to protect the vacuum chamber 17, the molecular pump assembly 14, and the vortex dry pump 12.

[0272] Before the device is put into operation, a helium mass spectrometer is required to detect leaks, and the leak rate is required to be <1.0E-7Pa.m3 / s.

[0273] The effects and methods described above are the same and will not be repeated here.

[0274] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the invention without departing from the principles and spirit of the invention, and all such changes should fall within the protection scope of the claims of the present invention.

Claims

1. A method for rapidly and automatically purging residual impurities from a vacuum chamber, characterized in that, include: Obtain the gas parameters of the clean gas in the inflation pipeline, and process the clean gas in the inflation pipeline according to the gas parameters; The treated clean gas is filled into the cavity, and the cavity pressure is measured. In response to the cavity pressure meeting the first switching condition, the coarse pumping step is initiated; In response to the cavity pressure meeting the second switching condition, the fine extraction step is initiated.

2. The method for rapid and automatic purging of residual gases in a vacuum cavity according to claim 1, characterized in that, The method further includes: In response to the chamber pressure meeting the first switching condition or the second switching condition, the filling of the chamber with the treated clean gas is stopped. In response to the vacuum level of the cavity meeting a preset target, the fine pumping step and / or the coarse pumping step are stopped.

3. The method for rapid and automatic purging of residual gases in a vacuum cavity according to claim 1, characterized in that, The method further includes: In response to a evacuation duration greater than or equal to a duration threshold, the fine evacuation step and / or coarse evacuation step are stopped, and the cavity is refilled with treated clean gas.

4. The method for rapid and automatic purging of residual impurities in a vacuum cavity according to claim 1, characterized in that, The pressure signal of the cleaned gas after treatment is less than or equal to the first preset pressure; The flow rate signal of the processed clean gas is less than or equal to the preset flow rate; The preset flow rate Q = 0.3VL / min, where V is the cavity volume.

5. The method for rapid and automatic purging of residual gases in a vacuum cavity according to claim 1, characterized in that, The gas parameters include flow rate and temperature signals; the process of processing the clean gas in the inflation pipeline according to the gas parameters includes: Based on the cavity volume and the gas parameters, the temperature of the clean gas in the inflation pipeline is adjusted to obtain the processed clean gas, and the temperature of the processed clean gas meets the preset temperature.

6. The method for rapid and automatic purging of residual gases in a vacuum cavity according to claim 1, characterized in that, The method further includes: Detect the concentration of residual impurities in the cavity; In response to the residual impurity concentration meeting a preset order of magnitude, the fine extraction step and / or coarse extraction step are stopped; And / or, In response to the residual impurity gas concentration meeting a preset quantity level, the filling of the cavity with treated clean gas is stopped.

7. An apparatus for rapidly and automatically purging residual gases from a vacuum chamber, used to implement the method for rapidly and automatically purging residual gases from a vacuum chamber as described in any one of claims 1 to 6, characterized in that, The device includes: An inflation module is used to fill the cavity with clean gas. The inflation module includes an inflation pipeline and a heating component. The input end of the inflation pipeline is connected to a gas source, and the output end of the inflation pipeline is connected to the cavity. The heating component is used to heat the clean gas in the inflation pipeline. A gas extraction module is used to extract gas from the cavity. The gas extraction module includes a coarse extraction component and a fine extraction component, both of which are connected to the cavity. The control module is used to monitor the gas parameters of the clean gas in the inflation pipeline and trigger the heating component to heat the clean gas according to the gas parameters, so that the treated clean gas is introduced into the cavity to replace the residual impurities in the cavity. The cavity pressure is monitored. When the cavity pressure reaches the first switching condition, the coarse extraction component is activated. When the cavity pressure reaches the second switching condition, the coarse extraction component is deactivated and the fine extraction component is activated.

8. The apparatus for rapid and automatic purging of residual impurities in a vacuum chamber according to claim 7, characterized in that, The control module is also used for: When the cavity pressure meets the first switching condition or the second switching condition, the inflation module is turned off. When the vacuum level of the chamber pressure meets the preset target, shut down the coarse pumping component and the fine pumping component; When the pumping time is greater than or equal to the time threshold, the inflation module is restarted.

9. The apparatus for rapid and automatic purging of residual impurities from a vacuum chamber according to claim 7, characterized in that, The inflation pipeline is equipped with a pressure reducing valve, a flow regulator, a check valve, and a first pneumatic valve; The pressure of the clean gas in the inflation pipeline is less than or equal to the first preset pressure; The flow rate of the clean gas in the inflation pipeline is less than or equal to the preset flow rate; The preset flow rate Q = 0.3VL / min, where V is the cavity volume.

10. The apparatus for rapid and automatic purging of residual impurities from a vacuum chamber according to claim 7, characterized in that, The inflation module also includes a flow monitoring component and a temperature monitoring component. The flow monitoring component is used to monitor the gas flow signal in the inflation pipeline and feed it back to the control module; The temperature monitoring component is used to monitor the gas temperature signal in the inflation pipeline and feed it back to the control module; The control module is also used to dynamically adjust the heating power of the heating component according to the cavity volume and the flow and temperature signals, so that the temperature of the clean gas in the inflation pipeline meets the preset temperature.

11. The apparatus for rapid and automatic purging of residual impurities from a vacuum chamber according to claim 7, characterized in that, The coarse pumping assembly includes a coarse pump and a second pneumatic valve, wherein the coarse pump is connected to the second pneumatic valve and the second pneumatic valve is connected to the cavity. The fine extraction assembly includes a molecular pump group and a third pneumatic valve, wherein the molecular pump group is connected to the third pneumatic valve, and the third pneumatic valve is connected to the cavity.

Images