Pressure control method and system and storage medium

Abstract

The invention relates to a pressure control method and system and a storage medium. The method comprises the steps that the monitored current angle of a butterfly valve and the monitored current pressure of a process cavity are obtained; determining the current air inflow of the process chamber according to the current angle and the current pressure of the butterfly valve; determining the predicted pressure of the process chamber at the next moment according to the current angle of the butterfly valve and the current air inflow; according to the set target pressure, the predicted pressure at the next moment and the current air inflow, the target angle of the butterfly valve is determined; and the operation path of the butterfly valve reaching the target angle of the butterfly valve in the shortest time is planned, and the butterfly valve is controlled according to the operation path so that pressure control over the process cavity can be achieved. The real-time air inflow is automatically estimated, the future pressure is accurately predicted, pressure overshoot is reduced, and the stabilization time is shortened; and the opening switching speed of the butterfly valve is maximized, the target angle is reached as soon as possible within the hardware bearing range, and then the pressure response speed is increased.

Description

TECHNICAL FIELD

[0001] The present application mainly relates to the field of semiconductor equipment, and in particular to a pressure control method, system and storage medium. BACKGROUND

[0002] In a vacuum process of a semiconductor chip manufacturing equipment, chamber pressure stability directly affects process quality. A common vacuum process chamber includes a gas inlet end, an exhaust port, and a vacuum pump. The mass flow controller (MFC) is arranged at the gas inlet end to provide a settable and stable gas inlet amount. The flow conductance of the exhaust pipeline is adjusted by the angle of the butterfly valve, and then the pressure of the chamber is adjusted. The vacuum pump provides a stable pumping speed to keep the exhaust pipeline characteristics constant.

[0003] The existing pressure control method has the following problems:

[0004] When the model between the pressure of the chamber and the angle of the butterfly valve is affected by the gas flow, it changes constantly during the process. The gas flow is usually not transmitted to the butterfly valve, resulting in a lack of key parameters in the pressure model and a large model error.

[0005] The nonlinear relationship between the chamber pressure and the angle of the butterfly valve is complex, and the pressure is jointly affected by the valve opening, the gas amount, and the performance of the vacuum pump. The single feedback control response is slow.

[0006] The butterfly valve angle adjustment does not consider the future pressure change trend. The controller only responds to the current pressure error, and cannot compensate for the future pressure deviation in advance.

[0007] The traditional control adopts fixed acceleration or fixed speed, which cannot fully utilize the ability of the motor control system of the butterfly valve, resulting in insufficient response capability. SUMMARY

[0008] An object of the present application is to provide a pressure control method, system and storage medium, which solves the problems of large pressure control error, slow control response, inability to compensate for future pressure deviation in advance, and insufficient response capability in the prior art.

[0009] According to one aspect of the present application, a pressure control method is provided, which is applied to a process chamber. The method comprises:

[0010] obtaining a monitored current angle of a butterfly valve and a current pressure of the process chamber;

[0011] determining a current gas inlet amount of the process chamber according to the current angle of the butterfly valve and the current pressure;

[0012] determining a predicted pressure of the process chamber at a next time according to the current angle of the butterfly valve and the current gas inlet amount;

[0013] determining a target angle of the butterfly valve according to a target pressure, a predicted pressure at a next time and the current intake amount of the process chamber;

[0014] planning a running path of the butterfly valve to reach the target angle of the butterfly valve in a shortest time, and controlling the butterfly valve according to the running path to realize the pressure control of the process chamber.

[0015] Optionally, the determining the current intake amount of the process chamber according to the current angle of the butterfly valve and the current pressure comprises:

[0016] acquiring a historical pressure of the process chamber, and determining a pressure change rate according to the historical pressure and the current pressure;

[0017] determining the current intake amount of the process chamber at the current time according to the current angle of the butterfly valve, the current pressure and the pressure change rate.

[0018] Optionally, the determining the current intake amount of the process chamber at the current time according to the current angle of the butterfly valve, the current pressure and the pressure change rate comprises:

[0019] determining a corresponding flow coefficient of the butterfly valve according to the current angle of the butterfly valve and a preset flow coefficient mapping relationship, wherein the flow coefficient mapping relationship satisfies that the flow coefficient monotonously increases with the increase of the opening degree of the butterfly valve;

[0020] determining the current intake amount of the process chamber at the current time according to the current pressure, the pressure change rate and the flow coefficient of the butterfly valve.

[0021] Optionally, the determining the target angle of the butterfly valve according to the target pressure, the predicted pressure at the next time and the current intake amount comprises:

[0022] determining a steady-state opening degree of the butterfly valve according to the target pressure and the current intake amount;

[0023] determining a dynamic correction amount according to the target pressure and the predicted pressure at the next time;

[0024] determining the target angle of the butterfly valve according to the steady-state opening degree of the butterfly valve and the dynamic correction amount.

[0025] Optionally, the method further comprises:

[0026] when reaching the next time, acquiring an actual pressure of the process chamber monitored;

[0027] determining a pressure error according to the actual pressure and the predicted pressure;

[0028] The correlation parameters are corrected based on the pressure error to await the next pressure control cycle, wherein the correlation parameters include the current intake volume and the predicted pressure.

[0029] Optionally, the method further includes:

[0030] The gas flow target is set according to the configuration information corresponding to the process chamber, and the target pressure of the process chamber is determined according to the gas flow target.

[0031] According to another aspect of this application, a pressure control system is also provided for use in a process chamber, the control system comprising:

[0032] A butterfly valve installed downstream of the process chamber, a vacuum gauge, a pressure controller, and a butterfly valve actuator installed on the process chamber;

[0033] The butterfly valve is used to feed back the current angle of the butterfly valve to the pressure controller, and the vacuum gauge is used to monitor the current pressure in the process chamber;

[0034] The pressure controller is used to determine the target angle of the butterfly valve based on the current angle and current pressure of the butterfly valve, and to plan the operating path of the butterfly valve to reach the target angle in the shortest time.

[0035] The butterfly valve actuator is used to control the butterfly valve according to the operating path to achieve pressure control of the process chamber.

[0036] Optionally, the pressure controller includes a flow estimator, a pressure predictor, and a target angle calculation module;

[0037] The flow estimator is used to determine the current air intake of the process chamber based on the current angle and current pressure of the butterfly valve.

[0038] The pressure predictor is used to determine the predicted pressure of the process chamber at the next moment based on the current angle of the butterfly valve and the current air intake.

[0039] The target angle calculation module is used to determine the target angle of the butterfly valve based on the set target pressure, the predicted pressure at the next moment, and the current intake volume.

[0040] Optionally, the control system includes a mass flow controller for setting a gas flow target based on configuration information corresponding to the process chamber, so as to determine the target pressure of the process chamber.

[0041] According to another aspect of this application, a computer-readable storage medium is also provided, having stored thereon computer-readable instructions that can be executed by a processor to implement the method described above.

[0042] Compared with existing technologies, this application achieves pressure control of the process chamber by acquiring the monitored current angle of the butterfly valve and the current pressure of the process chamber; determining the current air intake of the process chamber based on the current angle and current pressure of the butterfly valve; determining the predicted pressure of the process chamber at the next moment based on the current angle and current air intake of the butterfly valve; determining the target angle of the butterfly valve based on the set target pressure, the predicted pressure at the next moment, and the current air intake; planning the operating path of the butterfly valve to reach the target angle in the shortest time; and controlling the butterfly valve according to the operating path. It automatically estimates the real-time air intake, accurately predicts future pressure, reduces pressure overshoot, shortens stabilization time, and maximizes the butterfly valve opening switching speed, reaching the target angle as quickly as possible within the hardware's tolerance, thereby accelerating the pressure response speed. Attached Figure Description

[0043] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings, wherein:

[0044] Figure 1 A schematic diagram of a pressure control system structure according to one aspect of this application is shown.

[0045] Figure 2 A schematic diagram of the framework of a process chamber pressure control system according to an embodiment of this application is shown;

[0046] Figure 3 A schematic flowchart of a pressure control method according to one aspect of this application is shown.

[0047] Figure 4 A schematic diagram showing the change of butterfly valve angle in one embodiment of this application is shown;

[0048] Figure 5 This illustration shows a flowchart of parameter correction in one embodiment of the present application;

[0049] Figure 6 This illustration shows a schematic diagram of different intake flow rates in one embodiment of this application;

[0050] Figure 7 This diagram illustrates different pressure values ​​in one embodiment of the present application.

[0051] The same or similar reference numerals in the accompanying drawings represent the same or similar parts. Detailed Implementation

[0052] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0053] Many specific details are set forth in the following description in order to provide a full understanding of this application. However, this application may also be implemented in other ways different from those described herein, and therefore this application is not limited to the specific embodiments disclosed below.

[0054] In the description of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0055] Furthermore, the terms “up,” “down,” “left,” “right,” “top,” “bottom,” “horizontal,” and “vertical” used in the following description should be understood as the orientations shown in the paragraph and related figures. This relative terminology is for illustrative purposes only and does not imply that the described device must be manufactured or operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0056] It is understood that although terms such as “first,” “second,” “third,” etc., may be used here to describe various pipes, channels, components, areas, layers, and / or parts, these components, areas, layers, and / or parts should not be limited by these terms, and these terms are only used to distinguish different pipes, channels, components, areas, layers, and / or parts.

[0057] Figure 1 The diagram shows a pressure control system structure according to one aspect of this application, applied to a process chamber 10. The control system includes: a butterfly valve 20 installed downstream of the process chamber 10, a vacuum gauge 30 installed on the process chamber 10, a pressure controller 40, and a butterfly valve actuator 50.

[0058] The butterfly valve 20 is used to feed back the current angle of the butterfly valve to the pressure controller 40, and the vacuum gauge 30 is used to monitor the current pressure in the process chamber 10. The pressure controller 40 is used to determine the target angle of the butterfly valve based on the current angle of the butterfly valve and the current pressure, and to plan the operating path of the butterfly valve 20 to reach the target angle in the shortest time. The butterfly valve driver 50 is connected to the butterfly valve 20 and is used to control the butterfly valve 20 according to the operating path to achieve pressure control of the process chamber 10.

[0059] The semiconductor process chamber is the core of silicon wafer processing. During the process, a controllable process gas is introduced. The gas originates from a gas source, and its flow rate is controlled by a mass flow controller. A butterfly valve and a vacuum pump are installed downstream of the process chamber. A vacuum gauge is installed on the chamber to monitor the pressure inside, and the butterfly valve provides feedback on its angle. A pressure controller receives and processes the data, calculating the preset opening degree of the butterfly valve—the target angle the valve can potentially open to—based on the current pressure in the chamber monitored by the vacuum gauge and the current angle of the butterfly valve. Thus, under constraints of maximum speed and maximum acceleration, and with the goal of minimizing the movement time, a path is planned for the butterfly valve to reach the target angle. This path is the angular trajectory of the butterfly valve from its current angle to the target angle. A butterfly valve actuator then controls the butterfly valve to execute closed-loop motion control according to the planned angular trajectory.

[0060] In one embodiment of this application, the pressure controller includes a flow estimator, a pressure predictor, and a target angle calculation module; the flow estimator is used to determine the current air intake of the process chamber based on the current angle of the butterfly valve and the current pressure; the pressure predictor is used to determine the predicted pressure of the process chamber at the next moment based on the current angle of the butterfly valve and the current air intake; the target angle calculation module is used to determine the target angle of the butterfly valve based on the set target pressure, the predicted pressure at the next moment, and the current air intake.

[0061] like Figure 2 As shown, the semiconductor process chamber is the core location in silicon wafer processing. During the process, a controllable process gas is introduced. The gas originates from a gas source, and its flow rate is controlled by a mass flow controller. A butterfly valve and a vacuum pump are installed downstream of the process chamber. A vacuum gauge is installed on the chamber. The pressure controller includes a flow estimator, a pressure predictor, a module for target angle calculation, and a module for trajectory planning. The chamber pressure and angle signals are transmitted to the flow estimator. The estimated flow rate is transmitted to the pressure predictor, which transmits the predicted future pressure and estimated inlet flow rate to the target angle calculation module. The target angle calculation module calculates the target angle of the butterfly valve and transmits it to the trajectory planning module. The trajectory planning module then transmits the planned trajectory to the butterfly valve, allowing the butterfly valve actuator to control the butterfly valve according to the target angle.

[0062] In one embodiment of this application, the control system includes a mass flow controller, used to set a gas flow target based on configuration information corresponding to the process chamber, so as to determine the target pressure of the process chamber.

[0063] Based on the process configuration information (Recipe), the process execution unit sets the target flow rate value to the pressure controller. The MFC then controls the gas flow rate according to this target value to determine the target pressure. This target pressure refers to the pressure value required to be achieved in the process chamber. The required opening degree of the butterfly valve is then calculated to coordinate with the vacuum pump to adjust the pressure within the process chamber to the target pressure.

[0064] Figure 3 The diagram shows a pressure control method according to one aspect of this application, applied to a process chamber, the method comprising: steps S11 to S15.

[0065] Step S11: Obtain the current angle of the monitored butterfly valve and the current pressure of the process chamber.

[0066] A butterfly valve and a vacuum pump are installed downstream of the process chamber. The current angle of the butterfly valve can be obtained by receiving feedback signals from the valve's angle. A vacuum gauge is installed on the process chamber to monitor the pressure inside, thus obtaining the current pressure of the process chamber.

[0067] Step S12: Determine the current air intake volume of the process chamber based on the current angle and current pressure of the butterfly valve.

[0068] It automatically estimates the real-time intake volume to obtain the most critical factors affecting the chamber pressure; it can estimate based on the current angle of the butterfly valve and the current pressure in the process chamber.

[0069] In one embodiment of this application, the historical pressure of the process chamber can be obtained, and the pressure change rate can be determined based on the historical pressure and the current pressure; the current air intake of the process chamber at the current moment can be determined based on the current angle of the butterfly valve, the current pressure, and the pressure change rate.

[0070] The rate of change of chamber pressure at the current moment is calculated by combining the historical and current pressures of the process chamber, thereby reflecting the dynamic trend of pressure change. The current intake volume is then calculated based on the dynamic pressure change trend, quantifying the relationship between the pressure change rate and the intake volume.

[0071] Furthermore, the corresponding butterfly valve flow coefficient is determined based on the current angle of the butterfly valve and a preset flow coefficient mapping relationship, wherein the flow coefficient mapping relationship satisfies that the flow coefficient increases monotonically with the increase of the butterfly valve opening; the current air intake of the process chamber at the current moment is determined based on the current pressure, the pressure change rate, and the butterfly valve flow coefficient.

[0072] Based on current pressure Determine the rate of change of pressure based on historical pressure. The current angle of the butterfly valve is According to the current angle The corresponding butterfly valve flow coefficient is determined by the preset flow coefficient mapping relationship. The preset flow coefficient mapping relationship satisfies Butterfly valve angle The value increases monotonically as it increases, when When it is 0° The value is 0; this flow coefficient mapping table can be calibrated using experimental data, such as... When it is 30° The value is 5. Therefore, based on the current pressure... Pressure change rate Balance coefficient K and butterfly valve flow coefficient Estimate current intake volume :

[0073] ;

[0074] In the formula, K is the system gain coefficient. Calculated based on current and historical pressures, taking time k as an example:

[0075]

[0076] in, This represents the pressure in the process chamber at time k. This represents the pressure in the process chamber at time k-1. This represents the rate of pressure change in the process chamber at time k;

[0077] The smoothing coefficient is a weighting factor used to measure the historical inertia of the pressure change rate and the current response. It can be calibrated by the sensor (vacuum gauge) noise level and the system's dynamic response requirements. It represents the time interval between discrete times (the time difference between time k and time k-1).

[0078] By quantifying the relationship between opening degree and flow capacity through the flow coefficient of the butterfly valve, subsequent experimental calibration can be used to adapt butterfly valves with different structures.

[0079] Step S13: Determine the predicted pressure of the process chamber at the next moment based on the current angle of the butterfly valve and the current air intake volume.

[0080] Using the estimated current intake volume Current angle of butterfly valve Predicting the pressure in the next moment:

[0081]

[0082] Pressure is predicted by combining pressure change trends with flow estimation, resulting in more accurate pressure prediction and enabling "early action," which means adjusting the butterfly valve before pressure deviation occurs, reducing pressure overshoot, shortening stabilization time, and maintaining stability even during intake step changes.

[0083] Step S14: Determine the target angle of the butterfly valve based on the set target pressure, the predicted pressure at the next moment, and the current intake volume.

[0084] Based on the estimated flow rate, target pressure, and predicted future pressure, the butterfly valve angle for the future equilibrium state is estimated. Using only existing pressure sensors and butterfly valve position feedback signals, combined with the estimated current intake air volume and the predicted pressure for the next moment, the target angle of the butterfly valve can be calculated without the need for additional sensors, thus reducing hardware costs.

[0085] In one embodiment of this application, a gas flow target is set according to the configuration item information corresponding to the process chamber, and a target pressure of the process chamber is determined according to the gas flow target.

[0086] Based on the process configuration information (Recipe), the process execution unit sets the target flow rate value to the pressure controller. The MFC then controls the gas flow rate according to this target value to determine the target pressure. This target pressure refers to the pressure value required to be achieved in the process chamber. The required opening degree of the butterfly valve is then calculated to coordinate with the vacuum pump to adjust the pressure within the process chamber to the target pressure.

[0087] In one embodiment of this application, the steady-state opening of the butterfly valve is determined based on the set target pressure and the current intake volume; a dynamic correction amount is determined based on the set target pressure and the predicted pressure at the next moment; and the target angle of the butterfly valve is determined based on the steady-state opening of the butterfly valve and the dynamic correction amount.

[0088] The target angle of the butterfly valve is determined by the steady-state opening component and the dynamic correction amount. The steady-state opening component ensures that the pressure remains stable at the set target pressure value in steady state, while the dynamic correction amount is used to compensate for the deviation between the future pressure and the target pressure.

[0089] Specifically, based on the set target pressure The predicted pressure P at the next moment c,k+1 and current air intake volume The target butterfly valve angle value corresponding to the calculated target pressure:

[0090]

[0091] To ensure that the pressure in the process chamber eventually stabilizes at the target pressure The set desired opening angle of the butterfly valve is the control command input to the butterfly valve actuator, taking into account both steady-state adaptation and dynamic deviation compensation. For steady-state aperture components, This is a dynamic correction value.

[0092] Butterfly valve flow coefficient The inverse function, with the flow coefficient value as input. The output is the corresponding butterfly valve opening degree. . The strength of the correction for the butterfly valve opening caused by the pressure deviation is determined through experimental calibration, such as parameter tuning based on the PID control principle. The larger the value, the more sensitive the pressure deviation is to the correction of the opening degree; If the value is too small, the dynamic response will be slow; if it is too large, it will easily cause system oscillation.

[0093] Step S15: Plan the operating path of the butterfly valve to reach the target angle of the butterfly valve in the shortest time, and control the butterfly valve according to the operating path to achieve pressure control of the process chamber.

[0094] like Figure 4 As shown, the butterfly valve angle is adjusted from the current angle θ0 to the target angle. Butterfly valves can move to the target angle in the shortest time, shortening the pressure response time. Under the constraints of maximum speed and maximum acceleration, the butterfly valve constructs the shortest angular trajectory, maximizing the opening switching speed and reaching the target angle as quickly as possible within the hardware's tolerance, thereby accelerating the pressure response speed.

[0095] In one embodiment of this application, the method further includes: when the next moment is reached, acquiring the actual pressure of the monitored process chamber; and determining a pressure error based on the actual pressure and the predicted pressure.

[0096] The correlation parameters are corrected based on the pressure error to await the next pressure control cycle, wherein the correlation parameters include the current intake volume and the predicted pressure.

[0097] like Figure 5 As shown, ;in, P represents the error between the actual pressure and the predicted pressure. actual The pressure P was measured using a vacuum gauge. predict It is the predicted chamber pressure, i.e., P c,k+1 Based on the obtained errors, the butterfly valve conductance, intake flow rate estimate, and pressure estimate are corrected by multiplying the error by the corresponding coefficient and adding it to the initial predicted value.

[0098]

[0099]

[0100]

[0101] like Figure 6 The diagram shows different intake volume values, including the estimated intake volume, the actual intake volume, and the set intake volume value (i.e., the target intake volume value to be achieved). The pressure values ​​of the process chamber are as follows: Figure 7 As shown, this includes the predicted pressure value, the actual pressure value, and the set target pressure value. The predictor parameters (current pressure, current intake volume, butterfly valve angle) are updated, and the system waits for the next cycle. During operation, the model parameters are automatically adjusted to adapt to hardware aging, changes in operating load, and other factors.

[0102] According to another aspect of this application, a computer-readable storage medium is also provided, having stored thereon computer-readable instructions that can be executed by a processor to implement the pressure control method as described above.

[0103] When a pressure control method is implemented as a computer program, it can also be stored as an article of manufacture in a computer-readable storage medium. For example, a computer-readable storage medium may include, but is not limited to, magnetic storage devices (e.g., hard disks, floppy disks, magnetic stripes), optical discs (e.g., compact discs (CDs), digital multifunction discs (DVDs)), smart cards, and flash memory devices (e.g., electrically erasable programmable read-only memory (EPROM), cards, sticks, key drives). Furthermore, the various storage media described herein can represent one or more devices and / or other machine-readable media for storing information. The term "machine-readable medium" may include, but is not limited to, wireless channels and various other media (and / or storage media) capable of storing, containing, and / or carrying code and / or instructions and / or data.

[0104] It should be understood that the embodiments described above are merely illustrative. The embodiments described herein may be implemented in hardware, software, firmware, middleware, microcode, or any combination thereof. For hardware implementation, the processor may be implemented within one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, and / or other electronic units designed to perform the functions described herein, or combinations thereof.

[0105] Some aspects of this application can be executed entirely by hardware, entirely by software (including firmware, resident software, microcode, etc.), or by a combination of hardware and software. The aforementioned hardware or software may be referred to as a "data block," "module," "engine," "unit," "component," or "system." The processor may be one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DAPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, or combinations thereof. Furthermore, aspects of this application may manifest as computer products residing in one or more computer-readable media, including computer-readable program code. For example, computer-readable media may include, but are not limited to, magnetic storage devices (e.g., hard disks, floppy disks, magnetic tapes, etc.), optical discs (e.g., compressed CDs, digital multifunction DVDs, etc.), smart cards, and flash memory devices (e.g., cards, sticks, key drives, etc.).

[0106] A computer-readable storage medium may contain a propagated data signal containing computer program encoding, for example, on baseband or as part of a carrier wave. This propagated signal may take various forms, including electromagnetic, optical, and so on, or suitable combinations thereof. A computer-readable storage medium can be any other type of computer-readable storage medium that can be connected to an instruction execution system, apparatus, or device to enable communication, propagation, or transmission of a program for use. The program encoding located on the computer-readable medium can be propagated through any suitable medium, including radio, cable, fiber optic cable, radio frequency signals, or similar media, or any combination of the above media.

[0107] The basic concepts have been described above. Obviously, for those skilled in the art, the above disclosure is merely illustrative and does not constitute a limitation of this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are suggested in this application, and therefore remain within the spirit and scope of the exemplary embodiments of this application.

[0108] Furthermore, this application uses specific terms to describe embodiments of the application. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic related to at least one embodiment of the application. Therefore, it should be emphasized and noted that "an embodiment," "one embodiment," or "an alternative embodiment" mentioned twice or more in different locations in this specification do not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the application can be appropriately combined.

[0109] In some embodiments, numbers describing the quantity of components and attributes are used. It should be understood that such numbers used in the description of embodiments are modified in some examples with the terms "approximately," "approximately," or "generally." Unless otherwise stated, "approximately," "approximately," or "generally" indicates that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may be changed depending on the characteristics required by individual embodiments. In some embodiments, numerical parameters should take into account specified significant digits and employ a general method of digit reservation. Although the numerical ranges and parameters used to confirm their breadth of scope in some embodiments of this application are approximate values, in specific embodiments, such values ​​are set as precisely as feasible.

Claims

1. A pressure control method applied to a process chamber, the method comprising: The method comprises: acquiring a current angle of a butterfly valve and a current pressure of the process chamber; determining a current intake of the process chamber according to the current angle of the butterfly valve and the current pressure; determining a predicted pressure of the process chamber at a next time according to the current angle of the butterfly valve and the current intake; determining a target angle of the butterfly valve according to a set target pressure, the predicted pressure at the next time and the current intake; planning a running path of the butterfly valve to reach the target angle of the butterfly valve in the shortest time, and controlling the butterfly valve according to the running path to realize pressure control of the process chamber.

2. The method of claim 1, wherein, The determination of the current intake of the process chamber according to the current angle of the butterfly valve and the current pressure comprises: acquiring a historical pressure of the process chamber, and determining a pressure change rate according to the historical pressure and the current pressure; determining the current intake of the process chamber at the current time according to the current angle of the butterfly valve, the current pressure and the pressure change rate.

3. The method of claim 2, wherein, The determination of the current intake of the process chamber at the current time according to the current angle of the butterfly valve, the current pressure and the pressure change rate comprises: determining a corresponding butterfly valve flow coefficient according to the current angle of the butterfly valve and a preset flow coefficient mapping relationship, wherein the flow coefficient mapping relationship satisfies that the flow coefficient monotonically increases with the increase of the opening degree of the butterfly valve; determining the current intake of the process chamber at the current time according to the current pressure, the pressure change rate and the butterfly valve flow coefficient.

4. The method of claim 1, wherein, The determination of the target angle of the butterfly valve according to the set target pressure, the predicted pressure at the next time and the current intake comprises: determining a steady-state opening degree of the butterfly valve according to the set target pressure and the current intake; determining a dynamic correction amount according to the set target pressure and the predicted pressure at the next time; determining the target angle of the butterfly valve according to the steady-state opening degree of the butterfly valve and the dynamic correction amount.

5. The method of claim 1, wherein, The method further comprises: when reaching the next time, acquiring a monitored actual pressure of the process chamber; determining a pressure error according to the actual pressure and the predicted pressure; correcting a related parameter according to the pressure error to wait for a next pressure control period, wherein the related parameter comprises the current intake and the predicted pressure.

6. The method of claim 1, wherein, The method further comprises: setting a gas flow target according to configuration item information corresponding to the process chamber, and determining a target pressure of the process chamber according to the gas flow target.

7. A pressure control system applied to a process chamber, the pressure control system comprising: The control system comprises: a butterfly valve installed downstream of the process chamber, a vacuum gauge installed on the process chamber, a pressure controller and a butterfly valve driver; the butterfly valve is used to feed back a current angle of the butterfly valve to the pressure controller, and the vacuum gauge is used to monitor a current pressure in the process chamber; the pressure controller is used to determine a target angle of the butterfly valve according to the current angle of the butterfly valve and the current pressure, and plan a running path of the butterfly valve to reach the target angle of the butterfly valve in the shortest time; the butterfly valve driver is used to control the butterfly valve according to the running path to realize pressure control of the process chamber.

8. The control system of claim 7, wherein, The pressure controller comprises a flow estimator, a pressure predictor, and a target angle calculation module; The flow estimator is configured to determine a current intake amount of the process chamber according to a current angle of the butterfly valve and a current pressure; The pressure predictor is configured to determine a predicted pressure of the process chamber at a next time according to the current angle of the butterfly valve and the current intake amount; The target angle calculation module is configured to determine a target angle of the butterfly valve according to a set target pressure, the predicted pressure at the next time, and the current intake amount.

9. The control system of claim 7, wherein, The control system comprises a mass flow controller configured to set a gas flow target according to configuration item information corresponding to the process chamber, so as to determine a target pressure of the process chamber.

10. A computer-readable storage medium having stored thereon computer-readable instructions, the computer-readable instructions comprising: The computer readable instructions can be executed by the processor to implement the method of any one of claims 1-6.

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