Method for analyzing influence of leak rate on water vapor pumping behavior in high vacuum system

Abstract

A method for analyzing the influence of the leak rate on the steam extraction behavior in a high vacuum system comprises the steps that the external steam leak rate of the system is quantified through a static pressure rise experiment, and an experiment extraction curve is obtained under various internal configurations; a three-dimensional finite element model is established based on an actual geometric structure, a heterogeneity adsorption-desorption kinetic equation with adsorption energy changing along with surface coverage logarithm is introduced, and key parameters such as an adhesion coefficient and adsorption site density are inversely calibrated by utilizing multiple groups of experimental curves; and finally, after the quasi-static equilibrium condition is verified, performing quantitative simulation analysis on the influence of different leak rates and spatial distribution of leak holes on the air exhaust process and the spatial uniformity of the pressure in the cavity based on the calibration model. According to the method, the problem that a traditional model depends on empirical parameters and neglects the leak rate space effect is solved, and an accurate quantitative basis can be provided for sealing design, leak diagnosis and performance optimization of a high-vacuum system.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of vacuum technology, and particularly relates to a method for analyzing the influence of leak rate on water vapor pumping behavior in a high vacuum system, and is particularly suitable for the fields of semiconductor manufacturing, thin film deposition, surface science, space simulation and the like which have strict requirements for vacuum environment. BACKGROUND

[0002] Vacuum technology is widely used in the fields of semiconductor manufacturing, thin film deposition, surface science and space simulation, and the vacuum acquisition and performance maintenance of a high vacuum system are directly related to the stability of related processes. The gas in the vacuum system mainly comes from the permeation of chamber walls, micro-leakage holes in the vacuum chamber, surface desorption of internal components in the chamber and gases introduced or generated during the process. Among them, water vapor is often the main residual gas component in the high vacuum system because it is ubiquitous in the environment and has strong adsorption and slow desorption characteristics on metal surfaces, which has a significant impact on the ultimate vacuum and pumping time of the system.

[0003] In a high vacuum chamber mainly made of stainless steel, the source of water vapor can be simplified into two ways: external leakage and internal surface desorption. To describe the change of water vapor pressure during pumping, the existing technology proposes a variety of pumping models based on the assumption of reversible monolayer adsorption, regarding the inner wall of the chamber as a reversible adsorption phase, using the adsorption isotherm and mass conservation equation to establish the pressure-time relationship, and some research work further considers the surface heterogeneity and complex geometry. However, this kind of method usually relies on the experience given adsorption kinetic parameters, lacks systematic calibration of key parameters combined with pumping experiments; to simplify the calculation, the pressure in the chamber is assumed to be uniform, which is difficult to reflect the local pressure difference caused by internal components such as louvers, anti-fouling plates and long pipelines; the external leak rate is usually ignored or simply equivalent, and there is a lack of means to analyze the influence of the size and spatial distribution of the leak hole on the pumping curve and the local water vapor pressure in the chamber based on the measured leak rate.

[0004] Therefore, there is an urgent need for a high-precision analysis method that can comprehensively consider the actual leak rate conditions, surface adsorption kinetics and complex geometry, to more realistically simulate and evaluate the pumping behavior of water vapor in a high vacuum system, and to provide reliable basis for system design, sealing optimization and leak diagnosis. SUMMARY

[0005] To address the aforementioned issues, this invention provides a method for analyzing the impact of leakage rate on water vapor pumping behavior in high vacuum systems. A water vapor adsorption-desorption kinetic model is introduced within a unified finite element simulation framework and combined with static pressure rise experiments and pumping experiments under different internal structural configurations. This method obtains water vapor adsorption kinetic parameters applicable to the target chamber, enabling quantitative assessment of the temporal evolution and spatial distribution of water vapor pressure under different external leakage rates and leak spatial distribution conditions. This provides a basis for evaluating the vacuum performance and optimizing the structure of complex high vacuum systems.

[0006] To achieve the above technical objectives, the present invention adopts the following technical solution:

[0007] A method for analyzing the effect of leakage rate on water vapor pumping behavior in a high vacuum system includes the following steps:

[0008] (1) The leakage rate of the high vacuum system is measured to obtain the external leakage rate of water vapor in the vacuum chamber; the vacuum chamber is pumped under at least two internal structure configurations, and the change of water vapor pressure over time is recorded to obtain the experimental water vapor pumping curve.

[0009] (2) Establish a three-dimensional geometric model corresponding to the vacuum chamber, set the inner wall of the chamber, internal components and leakage hole units, and obtain a finite element model including leakage rate setting;

[0010] (3) Introduce the water vapor adsorption-desorption kinetic equation into the finite element model, solve the model using the finite element method, and obtain the simulated water vapor extraction curve;

[0011] (4) Determine the adsorption kinetic parameters based on the matching between the experimental water vapor extraction curve and the simulated water vapor extraction curve;

[0012] (5) Based on the adsorption kinetic parameters, change the external leakage rate of water vapor and / or the spatial distribution of the leakage unit to solve for the change of water vapor pressure with time and the spatial distribution of water vapor pressure under different conditions.

[0013] In step (1), a static pressure rise experiment is preferably used to determine the total external leakage rate Q of the vacuum chamber. total .

[0014] In the static pressure rise experiment, the vacuum chamber is evacuated to a predetermined initial pressure by the vacuum acquisition system, then the connection between the chamber and the vacuum acquisition system is disconnected, and the pressure change in the chamber over time is recorded. The relationship between the chamber volume V and the pressure change rate dP is then analyzed. total The total external leakage rate Q is calculated using / dt. total Preferably, the total external leakage rate Q total Determine by the following formula: Where V is the chamber volume, dPtotal dt is the rate of pressure change.

[0015] The ambient temperature T, relative humidity RH and ambient total pressure P atm are combined to calculate the ambient water vapor pressure P. Preferably, P is determined by the relationship between the saturated vapor pressure of water and the relative humidity. The external water vapor leak rate Q is determined by the following equation: .

[0016] In step (1), the vacuum chamber is subjected to pumping experiments under different internal structural configurations, each of which is formed by adjusting the combination of internal components of the chamber, to obtain experimental curves of the water vapor pumping process under different internal structural configurations.

[0017] Under each internal structural configuration, the vacuum chamber is pumped to a predetermined vacuum state under the action of the vacuum acquisition system, then released to the atmosphere and kept for a preset time, so that the inner wall of the chamber and the surface of the internal components are fully exposed to the ambient water vapor.

[0018] After the preset time is reached, the vacuum acquisition system is started again to pump the vacuum chamber, and a residual gas analyzer (RGA) is used to measure the change of the water vapor pressure P(t) with time t during the pumping process.

[0019] The change curve of the water vapor pressure P(t) with time t is taken as the water vapor pumping curve under the corresponding internal structural configuration.

[0020] Preferably, the pumping experiments under each internal structural configuration use the same initial pumping conditions and pumping time, so as to compare the influence of different internal structural configurations on the water vapor pumping behavior.

[0021] In step (2), a three-dimensional geometric model corresponding to the vacuum chamber is established, which includes the inner wall of the chamber and the geometry of the internal components introduced according to the internal structural configuration.

[0022] In the three-dimensional geometric model, the surface area corresponding to the potential leak position such as the external opening, flange interface or instrument connection port is identified.

[0023] The inner wall of the chamber, the surface of the internal components and the surface area of the potential leak position are defined as boundaries in the finite element model for applying corresponding boundary conditions.

[0024] In the finite element model, the surface boundary representing the potential leak position is set as a leak hole unit, which is a boundary unit in the finite element for characterizing the micro-leak connection path between the external environment and the interior of the chamber.

[0025] The equivalent molecular flux boundary condition or the equivalent leak port boundary condition is applied on the leak hole unit to introduce the external gas leakage effect in the finite element model.

[0026] Preferably, the equivalent molecular flux J on the leak hole unit leak The equivalent surface A of the leak hole can be calculated according to the set water vapor external leak rate Q leak The finite element model containing the leak hole unit and the leak rate setting is obtained by conversion.

[0027] In step (3), the water vapor molecule transport process in the chamber and the adsorption-desorption behavior of the inner wall surface of the chamber are coupled and solved under the condition of molecular flow, and a simulated water vapor pumping curve is obtained.

[0028] Preferably, the adsorption-desorption kinetics equation adopts an adsorption model representing surface heterogeneity, and the surface adsorption energy E b The relationship between the surface coverage θ and the surface adsorption energy E .

[0029] Wherein, E1 is the initial adsorption energy, K Q is a proportional coefficient, and θ is the surface coverage.

[0030] Under this model, the water vapor adsorption flux J ads , the desorption flux J des , the residence time τ and the surface coverage θ preferably satisfy the following conservation relationship: , , , .

[0031] Wherein, S0 is the adhesion coefficient, n sites is the saturated adsorption site density, and J inc (t) is the incident molecular flux.

[0032] The incident molecular flux J inc can be calculated according to the relationship between the water vapor pressure P(t) in the chamber and the average thermal velocity of the molecules as follows: .

[0033] In the numerical solution process, by adjusting the adsorption-desorption kinetics parameters S0, n sites and E1, K Q , the simulated water vapor pumping curve has good consistency with the measured pumping curve in the initial pumping stage and the high vacuum stage.

[0034] Preferably, in step (4), the rationality of using the quasi-static equilibrium condition to solve the pumping process is confirmed by the quasi-static equilibrium condition.

[0035] The present application is based on the chamber volume V, the inner surface area A and the average molecular thermal velocity , combined with the vacuum pump speed S, to define the quasi-static equilibrium criterion threshold .

[0036] The present application defines the instantaneous relative change rate of water vapor pressure , for characterizing the time scale of pressure change in the pumping process.

[0037] When the pumping process satisfies , it is considered that the time scale of water vapor pressure change is much larger than the time scale of multiple flights and reflections of molecules in the chamber to establish spatial distribution, and the pumping process can be considered to satisfy the quasi-static equilibrium condition, and the molecular flow model and surface flux balance relationship are used to solve the time evolution of water vapor pressure inside the chamber under the assumption.

[0038] In step (5), after the adsorption-desorption kinetic parameters are calibrated in step (4), the parameters are fixed for subsequent simulation.

[0039] In the simulation working condition setting, the value of the water vapor external leakage rate Q is changed to construct working condition models under different leakage rate levels.

[0040] Preferably, the reference leakage rate and several multiples thereof can be selected as representative working conditions for analyzing the influence of leakage rate amplification on water vapor pumping curves and internal pressure distribution in the chamber.

[0041] At the same time, the distribution position of the leakage hole unit in the geometric model can be changed to construct working condition models under different leakage position combinations.

[0042] Under each leakage rate level and leakage position combination, the finite element model established in step (3) and the adsorption-desorption kinetic parameters calibrated in step (4) are used for numerical solution.

[0043] Through solving, the change of water vapor pressure inside the chamber with time P(t) and its spatial distribution under each working condition are obtained, which are used to characterize the influence of different leakage rate levels and leakage positions on the water vapor behavior in the high vacuum system.

[0044] Compared with the prior art, the present application has the following beneficial effects:

[0045] 1. The present application obtains the total external leakage rate of the vacuum chamber through the static pressure rise experiment, converts the water vapor external leakage rate by combining the ambient temperature and relative humidity, and applies the equivalent molecular flux to the boundary corresponding to the leakage hole unit, so that the leakage condition can be given by measurable physical quantities, and the simulation working condition has a good corresponding relationship with the actual working condition in terms of leakage rate level.

[0046] 2. The application introduces surface heterogeneity monolayer adsorption-desorption kinetics equation in the finite element model, associates the adsorption energy with the coverage, and uses the experimental pumping curve under various internal structure configurations to jointly calibrate the related parameters, so that the simulation results can more consistently reflect the water vapor pressure changes in the initial pumping stage and the high vacuum stage, and compared with the method of using only the simplified adsorption model, has certain advantages in describing the water vapor pumping process.

[0047] 3. The application establishes a complex geometry finite element model containing the inner wall of the chamber, the internal components and the leak hole unit, calculates the time evolution and spatial distribution of water vapor pressure under different external leak rates and leak position combination conditions under the condition of quasi-static equilibrium, can quantitatively analyze the vacuum level of the main chamber, the chamber door and the pump pipeline, and is used for comparing the influence of different sealing structures and internal component arrangements on the local vacuum degree, and provides a reference for the structure design and leakage diagnosis of the high vacuum system. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 is the general flowchart of the application;

[0049] Figure 2 is the curve graph of the total pressure and pressure rise rate varying with the pressure rise time in the example of the application;

[0050] Figure 3 is the curve graph of the water vapor pressure varying with the pumping time in the example of the application;

[0051] Figure 4 is the comparison graph of the simulation results and experimental data in the example of the application;

[0052] Figure 5 is the water vapor pressure change graph caused by different leak rates in the example of the application;

[0053] Figure 6 is the chamber water vapor pressure spatial distribution graph under different leak hole unit spatial distributions in the example of the application. DETAILED DESCRIPTION

[0054] The technical solutions of the application are described in detail, completely and clearly in combination with the drawings and examples, so that those skilled in the art can fully understand and implement the application according to the description.

[0055] Example 1

[0056] This example takes a set of stainless steel high vacuum chambers as an object, and describes a method for analyzing the influence of leak rate on the water vapor pumping behavior in a high vacuum system.

[0057] As Figure 1As shown, the method in this embodiment includes, in sequence: measuring the external leakage rate of water vapor, measuring the water vapor pumping curve, establishing a finite element model including leakage rate settings, introducing the water vapor adsorption-desorption kinetic equation, solving the simulated pumping curve and determining the adsorption kinetic parameters, and analyzing the influence of different leakage rates and the spatial distribution of leak holes on the water vapor pumping process and the spatial uniformity of pressure in the cavity.

[0058] The chamber is mainly made of SUS 316L and SUS 304 stainless steel, with typical internal dimensions of approximately 1050 mm × 830 mm × 770 mm. Louvers and anti-fouling panels can be installed inside to form different internal structural configurations according to experimental needs.

[0059] The vacuum generation system consists of a backing dry pump and a cryogenic pump connected in series, which can pump the chamber pressure to 10. -6 The vacuum monitoring unit is in the Pa range. It includes a full-range vacuum gauge and an RGA (Remote Gauge).

[0060] After the chamber is sealed, it is heated to 260°C and continuously evacuated under the action of the vacuum system to allow water molecules on the chamber wall to fully desorb. After the chamber cools naturally to room temperature, the valve between the vacuum system and the chamber is closed to isolate the chamber from the vacuum system.

[0061] Record the total pressure of the chamber under isolated conditions. Over time The change in pressure rise rate dP total / dt and chamber volume Substitute into the formula The total external leakage rate of the chamber was obtained. The curves showing the change in total pressure and its rate of pressure rise over time after chamber isolation are shown below. Figure 2 As shown, the total external leakage rate obtained in this embodiment is approximately 1.82 × 10⁻⁶. -4 Pa·L / s.

[0062] Under environmental conditions of 22°C room temperature and 64% relative humidity, the volume fraction of water vapor in the atmosphere is calculated to be approximately 1.7% based on the saturated water vapor pressure. Therefore, the total external leakage rate Q is... total Converted to external water vapor leakage rate, the external water vapor leakage rate is 3.1 × 10⁻⁶. -6 Pa·L / s, and this value will be used as the baseline external leakage rate Q0 in subsequent modeling.

[0063] To simulate the adsorption state of the chamber during typical use, the chamber is slowly vented from a high vacuum state to atmospheric pressure, and the chamber door is opened to expose the inner wall and the surface of the internal components to the atmospheric environment. This process is maintained for a preset time to allow the surface water molecules to be nearly saturated.

[0064] The chamber door was closed and the vacuum pumping system was started. The water vapor pressure was recorded by RGA as a function of time.

[0065] The following four internal configurations were selected for water vapor pumping experiments: (1) without shutter / without anti-fouling plate; (2) with shutter / without anti-fouling plate; (3) with shutter / with anti-fouling plate; (4) without shutter / with anti-fouling plate. As shown in FIG. 1, the water vapor pressure change curves measured under different internal configurations were used as experimental basis for adsorption kinetics parameter calibration. Figure 3

[0066] A three-dimensional geometric model corresponding to the chamber structure was established, which included the chamber inner wall, shutter, anti-fouling plate and other internal components, as well as the external interface position. The chamber inner wall, internal component surface and external interface surface were defined as boundaries in the finite element model, which were used to apply corresponding molecular flow flux boundary conditions.

[0067] The leakage hole units were set on the boundaries corresponding to the chamber door sealing ring and flange joint, and the reference water vapor external leakage rate was distributed to each leakage hole unit according to the equivalent area of each leakage hole unit, so that the total leakage rate in the finite element model was consistent with the reference external leakage rate Q0.

[0068] The water vapor adsorption-desorption kinetics boundary conditions were applied on the surface units of the chamber inner wall and internal components. In this embodiment, a monolayer adsorption model representing surface heterogeneity was used, which satisfies the following relationship between adsorption energy E b and surface coverage θ: .

[0069] The adsorption flux , sticking coefficient , surface coverage and incident molecular flux satisfy the following relationship: .

[0070] The desorption flux , number of adsorbed molecules per unit area and residence time satisfy the following relationship: .

[0071] The change of saturated adsorption site density and surface coverage over time satisfies the mass conservation: .

[0072] The residence time satisfies the Arrhenius relationship: .

[0073] wherein,​ is the frequency of the natural oscillation of the molecule, is the gas constant, is the thermodynamic temperature;

[0074] In the pressure range involved in the present embodiment, the gas flow in the chamber is in the molecular flow regime. To ensure the reasonableness of the finite element solution, the pumping process is checked according to the aforementioned quasi-static equilibrium criterion. The maximum value of η(t) calculated from the experimental pumping curve data is about 0.014 s -1 , which is much smaller than the threshold value η calculated according to the quasi-static equilibrium criterion formula qs = 1105.2 s -1 , so it can be considered that the pumping process satisfies the quasi-static equilibrium condition. Under the above molecular flow and quasi-static equilibrium conditions, the finite element model is solved to obtain the evolution of the water vapor pressure in the chamber over time and the spatial distribution.

[0075] To determine the adsorption kinetics parameters, the present embodiment sets the following parameter value ranges:

[0076] S0: 0.01-0.5; n sites : 3.3 x 10 -5 -8.3 x 10 -4 mol / m 2 ; E1: 80-100 kJ / mol; K Q : 10-50 kJ / mol.

[0077] The above parameter ranges are selected in reference to the reports in the published literature on the adsorption characteristics of water vapor on the surface of stainless steel, combined with the materials of the chamber and the actual pumping conditions.

[0078] Under the internal structure configuration of "no shutter / no anti-fouling plate", multiple parameter combinations are selected for simulation, the water vapor pumping curves are calculated respectively, and compared with the corresponding experimental results, from which the parameter combination that can simultaneously satisfy the trend of the initial pumping stage and the high vacuum stage is selected as the calibrated adsorption kinetics parameters. As Figure 4 shown, the water vapor pumping curve obtained by simulation using the calibrated parameters is in good agreement with the experimental curve.

[0079] After determining the adsorption kinetics parameters, the time evolution and spatial distribution of the water vapor pressure in the chamber under different working conditions are calculated by changing the external leakage rate of water vapor and the distribution of the leakage hole units.

[0080] As Figure 5As shown in the "no shutter / no anti-fouling plate" configuration, the external leakage rate is set to Q = Q0, 10Q0, 100Q0, 1000Q0 and 10000Q0 in turn, and the change of water vapor pressure at the RGA measurement point relative to the case without leakage rate is calculated respectively, for analyzing the change characteristics of water vapor pressure under different leakage levels.

[0081] As shown in the "no shutter / no anti-fouling plate" configuration, the external leakage rate is set to Q = Q0, 10Q0, 100Q0, 1000Q0 and 10000Q0 in turn, and the change of water vapor pressure at the RGA measurement point relative to the case without leakage rate is calculated respectively, for analyzing the change characteristics of water vapor pressure under different leakage levels. Figure 6 As shown in the "no shutter / no anti-fouling plate" configuration, the external leakage rate is set to Q = Q0, 10Q0, 100Q0, 1000Q0 and 10000Q0 in turn, and the change of water vapor pressure at the RGA measurement point relative to the case without leakage rate is calculated respectively, for analyzing the change characteristics of water vapor pressure under different leakage levels.

[0082] The present embodiment inversely calibrates the key adsorption parameters by fusing the water vapor external leakage rate measured by the static pressure rise experiment, the multi-configuration pumping experiment curve and the finite element model based on surface heterogeneity adsorption kinetics (adsorption energy changes with coverage), and constructs a high-fidelity simulation model. The technical problems of existing methods relying on empirical parameters, ignoring the spatial effect of leakage rate and being difficult to evaluate the local pressure distribution under complex structure are solved, and high-precision quantitative analysis of the influence caused by the size and spatial distribution of leakage rate is realized, providing a reliable basis for high-vacuum system design optimization and leakage diagnosis.

[0083] The specific embodiments of the present application are described above. It should be understood that the present application is not limited to the above specific embodiments, and those skilled in the art can make various modifications or modifications within the scope of the claims, which does not affect the essential content of the present application. In the case of no conflict, the above embodiments and the features in the embodiments can be combined with each other.

Claims

1. A method of analyzing the effect of leak rate on water vapor pumping behavior in a high vacuum system, characterized by, The method comprises the following steps: Step S1. Obtain measured data A static pressure rise experiment is performed on the target high vacuum system to measure the total external leak rate of the high vacuum system, and the total external leak rate is converted into a water vapor external leak rate according to environmental parameters; Water vapor pumping experiments are performed under at least two different internal structure configurations, and the change of water vapor pressure with time is recorded synchronously to obtain a plurality of experimental water vapor pumping curves; Step S2. Establish a finite element model including leak rate settings Based on the specific structure of the high vacuum system corresponding to the experiment in step S1, a three-dimensional geometric model including the inner wall of the chamber, internal components and potential leakage positions is established; In the three-dimensional geometric model, the potential leakage positions are set as leak hole units, and equivalent molecular flux boundary conditions are applied to the leak hole units according to the water vapor external leak rate, to obtain a finite element model including leak rate settings; Step S3. Simulate the water vapor pumping process In the finite element model, a water vapor adsorption-desorption kinetics equation is introduced, which includes: . Surface adsorption energy Relationship with surface coverage Relationship with surface coverage ； wherein, is the initial adsorption energy, is a proportionality coefficient characterizing the degree of surface heterogeneity; i. residence time of adsorbed molecules Arrhenius relationship with surface adsorption energy Arrhenius relationship with surface adsorption energy ； wherein, is the frequency of the intrinsic molecular oscillation, is the gas constant, is the thermodynamic temperature; ii. water vapor adsorption flux , desorption flux and surface coverage conservation relation over time t: ； ； ； wherein, is the adhesion coefficient, is the saturation adsorption site density, is the number of adsorbed molecules per unit area, is the incident molecular flux; iv. Incident molecular flux Relationship with water vapor pressure and average molecular thermal velocity : ； Based on the adsorption-desorption kinetics equation, the finite element model is solved to obtain a simulated water vapor pumping curve; Step S4. Calibrate the adsorption kinetics parameters The simulation water vapor pumping curve obtained in step S3 and the experimental water vapor pumping curve obtained in step S1 are matched, and the adhesion coefficient is determined by parameter optimization , saturated adsorption site density , initial adsorption energy and the proportion coefficient representing the degree of surface heterogeneity value; Step S5. Analyze the influence of leak rate on pumping behavior Based on the calibrated adsorption kinetics parameters, the water vapor external leak rate and / or the spatial distribution of the leak hole units are changed in the finite element model, and the change of water vapor pressure with time and the spatial distribution of water vapor pressure under different leak rate conditions are obtained through simulation, to realize quantitative analysis of the influence effect of leak rate.

2. The method of claim 1, wherein the water vapor is introduced into the high vacuum system at a pressure of 10"4 Pa or less. The leak hole units in step S2 are set at positions corresponding to external openings, flange interfaces or instrument connection ports.

3. The method of claim 1, wherein the method is used to analyze the effect of leak rate on water vapor pumping behavior in a high vacuum system. In step S2, the equivalent molecular flux boundary condition is applied by calculating the number of water vapor molecules entering the chamber through the leak hole units per unit time according to the water vapor external leak rate and the equivalent area of the leak hole units, and converting it into the equivalent molecular flux density on the boundary.

4. The method of claim 1, wherein the method is used to analyze the effect of leak rate on water vapor pumping behavior in a high vacuum system. In step S3, the finite element model is solved under quasi-static equilibrium conditions, specifically including: Based on the vacuum pump speed , the chamber volume , the chamber inner surface area and the average molecular thermal velocity , the quasi-static equilibrium criterion threshold is calculated: ； Computing the instantaneous relative rate of change of water vapor pressure ; When the following condition is satisfied during the pumping process the quasi-static equilibrium condition is used for the solution.

5. The method of claim 1, wherein the method is used to analyze the effect of leak rate on water vapor pumping behavior in a high vacuum system. In step S4, the parameter optimization method is to perform simulation calculation on a plurality of parameter combinations within a preset parameter range, and select the parameter combination that has the best fitting degree of the simulation curve and the experimental curve in the initial pumping stage and the high vacuum stage as the calibration result.

6. The method of claim 1, wherein the method is performed in a high vacuum system. In step S5, the quantitative analysis of the influence effect of leak rate includes: The influence of leak rate size on the ultimate vacuum degree of the system; The influence of leak rate size on the pumping time required to reach the target vacuum degree; The influence of the spatial distribution of the leak hole on the spatial uniformity of the water vapor pressure in the chamber; The influence of the leak hole position on the local vacuum degree of the key process area.

7. The method of claim 1, wherein the method is used to analyze the effect of leak rate on water vapor pumping behavior in a high vacuum system. In step S1, the calculation formula of the water vapor external leak rate Q is: ； wherein, the total external leak rate measured for the static pressure rise experiment, the ambient water vapor pressure, the ambient total pressure.

8. The method of claim 1, wherein the method is used to analyze the effect of leak rate on water vapor pumping behavior in a high vacuum system. In step S1, the internal structure configuration is realized by adjusting the installation combination mode of the louvers, anti-fouling plates, baffles or process tooling in the chamber.

9. The method for analyzing the influence of leak rate on water vapor pumping behavior in high vacuum system according to any one of claims 1-8, characterized in that, Further comprising step S6: based on the analysis results of step S5, optimizing the sealing design, leak detection strategy or process arrangement scheme of the high vacuum system.

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