Pressure control method, apparatus, and semiconductor process device

Abstract

Pressure control method, device and semiconductor process device. The method includes: acquiring in real time the actual pressure value in the process chamber (S1); calculating the pressure change amount of the actual pressure value (S2); comparing the pressure change amount with a preset value provided in advance, and when the pressure change amount is less than or equal to the preset value, controlling the actuator of the pressure regulating valve to maintain the current frequency, and controlling the opening degree change of the pressure regulating valve based on this frequency, and when the pressure change amount is greater than the preset value, controlling the frequency of the actuator to decrease according to a preset functional relationship until the actual pressure value reaches the target pressure value (S3), and controlling the opening degree change of the pressure regulating valve based on this frequency. This method solves the problem of overshoot pressure in the rapid control process of chamber pressure and suppresses the influence of pressure fluctuation on the process.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing technology, and more specifically, to a pressure control method, apparatus, and semiconductor process device.

Background Art

[0002] In fields such as semiconductor manufacturing and solar power generation, a process chamber such as an oxidation furnace is one of the most important devices in the semiconductor process. H2, HCL, excessive O2, a small amount of C2H2Cl2, and N2 entering the process chamber of the oxidation furnace need to undergo a chemical reaction under a certain pressure so that the thickness of the coating layer meets the requirements. Whether the pressure in the process chamber is greater or smaller than the set pressure affects the thickness of the coating layer. Therefore, it is necessary to stabilize the pressure in the process chamber, and how to accurately and quickly control the pressure in the chamber has become the core technical problem to be solved.

[0003] In the prior art, in a patent application with a publication number of CN111831022A, a chamber pressure control method for realizing rapid pressure control has been proposed based on the PTL (Pressure To Location) policy. Based on the high-speed valve opening characteristic of the pressure regulating valve, this technology dynamically and autonomously adjusts the PTL policy, that is, the closed-loop PID control coefficient, and adopts the calculation based on the PTL conversion coefficient Kn (the conversion coefficient between pressure change and the opening degree of the butterfly valve) and the PID coefficient to realize the fine adjustment of PID, and realizes the purpose of rapid and stable control of pressure.

[0004] Although this technology can perform high-speed pressure control, that is, it can quickly respond when the related parameters (flow rate, pressure, etc.) in the process change, due to the certain hysteresis characteristics of the pressure system, overshoot is likely to occur in overly rapid adjustments, and the fluctuation of the chamber pressure caused by the overshoot affects the process result.

Summary of the Invention

[0005] The present invention provides a pressure control method, apparatus, and semiconductor process device, and aims to solve the problem of overshoot pressure in the rapid control process of chamber pressure and suppress the influence of pressure fluctuations on the process.

[0006] In a first aspect, the present invention is a pressure control method applied to a process chamber of a semiconductor process device, and a pressure regulating valve for adjusting the pressure in the process chamber is provided on the gas pipeline of the process chamber, comprising: acquiring the actual pressure value in the process chamber in real time; calculating the amount of pressure change of the actual pressure value; comparing the amount of pressure change with a preset value provided in advance, and when the amount of pressure change is less than or equal to the preset value, controlling the actuator of the pressure regulating valve to maintain the current frequency, controlling the change in the opening degree of the pressure regulating valve based on the frequency, and when the amount of pressure change is greater than the preset value, controlling the frequency of the actuator to decrease according to a preset functional relationship, and controlling the change in the opening degree of the pressure regulating valve based on the frequency.

[0007] Optionally, calculating the amount of pressure change of the actual pressure value comprises: calculating a first difference value between a first actual pressure value in the process chamber and a target pressure value obtained at a first time; calculating a second difference value between a second actual pressure value in the process chamber and the target pressure value obtained at a second time; calculating a difference value between the first difference value and the second difference value, and a ratio between the difference value and a maximum difference value between an initial actual pressure value and the target pressure value in the process chamber as the amount of pressure change.

[0008] Optionally, calculating the amount of pressure change of the actual pressure value comprises: Calculating a first difference value between a first actual pressure value in the process chamber and the target pressure value, obtained at a first time; Calculating a second difference value between a second actual pressure value in the process chamber and the target pressure value, obtained at a second time; Calculating, as the pressure change amount, a ratio of a difference value between the first difference value and the second difference value to the first difference value; and

[0009] Optionally, controlling the frequency of the actuator to decrease according to a pre-provided functional relationship; Calculating a difference value between each obtained actual pressure value and the target pressure value; When the difference value is greater than zero, controlling the frequency of the actuator to decrease according to the pre-provided functional relationship, and the pre-provided functional relationship satisfies that the difference value corresponding to each actual pressure value corresponds one-to-one with the frequency of the actuator; and

[0010] Optionally, the pre-provided functional relationship is F i+1 = K × F i where F i is the current frequency of the actuator, F i+1 is the next frequency of the actuator, the possible values of K are 0 to 1, i = 1, 2, 3, …, n, and F 1 is the initial frequency of the actuator, and the initial frequency is the maximum frequency at which resonance of the actuator does not occur.

[0011] Optionally, controlling a change in the opening degree of the pressure regulating valve based on the frequency includes controlling a change in the opening degree of the pressure regulating valve using a PID closed-loop control method based on the obtained actual pressure value and a pre-provided target pressure value.

[0012] Optionally, the actual pressure value is an absolute pressure value inside the process chamber, or Alternatively, the actual pressure value is a relative value between the internal pressure of the process chamber and the atmospheric pressure.

[0013] In a second aspect, the present invention provides a chamber pressure control device comprising a pressure collector, a pressure controller, and an actuator, wherein the pressure collector is used to collect in real time the actual pressure value in the process chamber, the pressure controller is used to execute the pressure control method described in the first aspect, and the actuator is used to control the change in the opening degree of the pressure regulating valve based on the frequency output by the pressure controller.

[0014] Optionally, the actuator is a generator that controls the change in the opening degree of the pressure regulating valve, and the frequency of the actuator is the rotational frequency of the generator.

[0015] Optionally, the pressure regulating valve comprises an elastic expansion member used to adjust the opening degree of the pressure regulating valve.

[0016] In a third aspect, the present invention provides a semiconductor process device comprising a process chamber and a pressure regulating valve provided on the gas pipeline of the process chamber, further comprising the chamber pressure control device described in the second aspect.

[0017] The beneficial effects of the present invention are The present invention acquires the actual pressure value in the process chamber in real time during the pressure control process, calculates the amount of pressure change of the actual pressure value, compares the amount of pressure change with a preset value provided in advance, and when the amount of pressure change is less than or equal to the preset value, controls the actuator of the pressure regulating valve to maintain the current frequency, controls the change in the opening degree of the pressure regulating valve based on this frequency, and when the amount of pressure change is less than the preset value, controls the frequency of the actuator to decrease according to a preset functional relationship, controls the change in the opening degree of the pressure regulating valve based on this frequency. During the pressure control process, as the difference value between the actual pressure value and the target pressure value gradually decreases, the actuator frequency also gradually decreases. That is, as the pressure difference value gradually becomes smaller, the speed of the change in the opening degree of the pressure regulating valve also gradually slows down. Therefore, the phenomenon of pressure overshoot caused by pressure changes or flow rate changes during the pressure control process can be effectively reduced, the response time of pressure control becomes faster, pressure control becomes more stable, and when the gas flow rate in the process chamber pressure control system continuously changes in steps within a specified time, this method can significantly achieve the effect of preventing pressure overshoot and improve the quality of the process.

[0018] The device of the present invention has other features and advantages, and these features and advantages will become apparent from the drawings incorporated herein and specific embodiments, or are described in detail in the drawings and specific embodiments incorporated herein, and these drawings and specific embodiments are used together to explain the specific principles of the present invention.

Brief Description of the Drawings

[0019] The above and other objects, features, and advantages of the present invention will become more apparent by describing exemplary embodiments of the present invention in more detail in conjunction with the drawings. In the exemplary embodiments of the present invention, the same reference numerals generally denote the same members.

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0020] In order to solve the problems existing in the prior art, the present invention provides a pressure control method, device, and semiconductor process device. This pressure control method is based on the negative feedback characteristics of the input and output of the pressure system. In the entire pressure closed-loop control process, a method of gradually performing frequency conversion of the actuator is adopted to solve the problem of pressure overshoot in the rapid control process of the chamber pressure, and the influence of pressure fluctuations on the process can be minimized. Such a method can be applied to different pressure control systems.

[0021] Hereinafter, the present invention will be described in more detail with reference to the drawings. Although preferred embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms without being limited by the embodiments described herein. Rather, these embodiments are provided to make the present invention more thorough and complete, and to fully convey the scope of the present invention to those skilled in the art.

[0022] Embodiment 1 As shown in Figure 1, the pressure control method specifically includes the following steps.

[0023] S1: Obtain the actual pressure value in the process chamber in real time.

[0024] Optionally, the actual pressure value may be the absolute pressure value inside the process chamber (for example, the pressure detected at the exhaust port of the process chamber may be used as the actual pressure value), or the actual pressure value may be the relative value between the pressure inside the process chamber and the atmospheric pressure. Therefore, the chamber pressure control method provided by this embodiment may be applied to an absolute pressure control method or a relative pressure control method.

[0025] S2: Calculate the pressure change amount of the actual pressure value.

[0026] S3: Compare the pressure change amount with a preset value provided in advance. When the pressure change amount is less than or equal to the preset value, control the actuator of the pressure regulating valve to maintain the current frequency, and control the opening change of the pressure regulating valve based on this frequency. When the pressure change amount is greater than the preset value, control the frequency of the actuator to decrease according to a preset functional relationship, and control the opening change of the pressure regulating valve based on this frequency.

[0027] In this embodiment, in step S3 above, controlling the opening change of the pressure regulating valve based on this frequency includes controlling the opening change of the pressure regulating valve using a PID closed-loop control method until the actual pressure value reaches the preset target pressure value based on the obtained actual pressure value and the preset target pressure value.

[0028] Specifically, in step S1 above, the actual pressure value inside the process chamber is obtained in real time, and the difference between this value and the preset target pressure value is compared. When the actual pressure value does not reach the target pressure value, the opening change of the pressure regulating valve is controlled using a PID closed-loop control method until the actual pressure value reaches the target pressure value. The PID closed-loop control method is a well-known technology in this field and will not be described here.

[0029] Also, prior to performing the closed-loop control of the chamber pressure, calculate the amount of change in the actual pressure value, compare this with a preset value provided in advance, and then, in the process of performing the closed-loop control of the chamber pressure, determine whether to control the actuator to maintain the current frequency or to control the frequency of the actuator to decrease according to a preset functional relationship according to the comparison result. Thereby, by appropriately adjusting the frequency of the actuator based on the amount of pressure change as a determination basis, the phenomenon of pressure overshoot due to pressure change or flow rate change during the pressure control process can be effectively reduced, and the pressure control response time can be made faster and the pressure control can be performed more stably.

[0030] In some selectable embodiments, in step S2, calculating the amount of change in the actual pressure value includes calculating a first difference value between a first actual pressure value in the process chamber and the target pressure value, obtained at a first time; calculating a second difference value between a second actual pressure value in the process chamber and the target pressure value, obtained at a second time; calculating the ratio of the difference value between the first difference value and the second difference value to the maximum difference value between the initial actual pressure value in the process chamber and the target pressure value, or taking the ratio of the amount of pressure change to the first difference value of the first difference value and the second difference value. This ratio is taken as the amount of pressure change.

[0031] The initial actual pressure value in the process chamber refers to the actual pressure value in the process chamber obtained at the initial time when performing the closed-loop control of the chamber pressure. In the process of performing the closed-loop control of the chamber pressure, since the actual pressure value in the process chamber gradually approaches the target pressure value until it reaches the target pressure value, the difference value between the initial actual pressure value and the target pressure value is the maximum value among all the difference values between the obtained actual pressure values and the target pressure value, and is referred to as the "maximum difference value between the initial actual pressure value and the target pressure value".

[0032] Specifically, the initial actual pressure value in the process chamber may be obtained by a pressure sensor, and the target pressure value is a set value which is the required pressure value for the process. Also, at the initial time when the closed-loop control of the chamber pressure is performed, the frequency of the actuator is an initial frequency that can be determined based on the maximum difference value. In practice, the initial frequency may be set by an empirical value, for example, it may be the maximum frequency that does not cause resonance of the actuator.

[0033] In some selectable embodiments, in step S3, the pre-provided functional relationship is F i+1 =K×F i where F i is the current frequency of the actuator, F i+1 is the next frequency of the actuator, the possible values of K are 0 to 1, i = 1, 2, 3, …, n, and F 1 is the initial frequency of the actuator, and the initial frequency is the maximum frequency that does not cause resonance of the actuator.

[0034] For example, the pressure change amount for each frequency conversion (the change value of the real-time difference value with respect to the maximum pressure difference value) may be a certain ratio of the difference value between the actually measured actual pressure value in the process chamber and the set target pressure value. Among them, the smaller the preset value of the pressure change amount used for comparison with the pressure change amount, the higher the frequency for adjusting the actuator frequency, which corresponds to a smoothed frequency conversion. Under specific circumstances, no overshoot phenomenon occurs during the frequency conversion step. If the preset value of the pressure change amount is 5%, it is necessary to change the pressure change amount for the next frequency conversion by more than 5%. The degree of frequency conversion can be set according to the actual situation. For example, each time, the frequency of the actuator is adjusted to 10% of the previous frequency. Specifically, it is as follows.

[0035] Method 1: The actuator frequency is determined by the change value of the difference between the actual pressure value obtained in real time and the target pressure value with respect to the maximum difference value (i.e., the absolute pressure change value). For example, let Pn be the target pressure value, P1 be the initial pressure value, and P2 and P3 be the actual pressure values at intermediate times in sequence. The difference values between the actual pressure values and the target pressure value at different times are ΔP1 = Pn - P1, ΔP2 = Pn - P2, and ΔP3 = Pn - P3.

[0036] If the absolute pressure change amount is set as (ΔP1 - ΔP2) / ΔP1 > 5%, within the pressure change range from P1 to P2, the initial frequency F 1 is executed, and after P2, the execution frequency is adjusted from F 2 = 10%×F 1 is adjusted.

[0037] If the absolute pressure change amount is set as (ΔP1 - ΔP2) / ΔP1 ≤ 5%, the execution frequency after P2 is maintained at the current frequency F 1 is maintained.

[0038] Method 2: The frequency of the actuator may be determined by the change value of the difference between the actual pressure value obtained this time and the previous difference value of the difference between the actual pressure value and the target pressure value (i.e., the relative pressure change value). For the cases of (ΔP1 - ΔP2) / ΔP1 > 5% or (ΔP1 - ΔP2) / ΔP1 ≤ 5%, the explanations are omitted here.

[0039] The above are only examples, and 5% is just a threshold value set by oneself (i.e., the preset value). If it is less than 5%, the current frequency may be maintained. Also, the value of the actuator frequency conversion can be defined according to actual requirements, and 10% is just an example. Specifically, it is adjusted according to the response time. The difference value between the actual pressure value and the target pressure value gradually decreases from the maximum difference to the set pressure value, and the degree of frequency conversion becomes larger as time goes by.

[0040] Note that the actuator is a generator of a pressure regulating valve, the frequency of the actuator is the generator rotation frequency, and the smaller the difference value between the actual pressure value and the target pressure value in the process chamber, the lower the corresponding generator rotation speed. That is, the smaller the operating speed of the pressure regulating valve, the slower the valve opening change. Therefore, the smaller the difference value, the more stable the valve operation.

[0041] The method of this embodiment realizes the optimization of control by combining the input and output negative feedback characteristics of the pressure control system to change the frequency of the pressure regulating valve actuator in advance. The input and output negative feedback characteristics of the pressure control system refer to the process characteristics that the system pressure changes with the pressure setting at a constant flow rate over a certain period and finally stabilizes to the set pressure. The final state of system stabilization means that the pressure detection value is equal to the set pressure.

[0042] Based on the relationship between the actually measured actual pressure in the chamber and the set target pressure, the real-time state is determined, the frequency of the generator is changed based on the negative feedback characteristics, and further, the pressure control parameters are changed, the actuator frequency is calculated based on different pressure difference values, and the fine adjustment of the pressure regulating valve opening is performed, thereby realizing the purpose of quickly and stably controlling the pressure.

[0043] As one of the preferred embodiments, in step S3, controlling the frequency of the actuator to decrease according to a pre-provided functional relationship specifically includes: calculating the difference value between each obtained actual pressure value and the target pressure value; when the difference value is greater than zero (i.e., the actual pressure value does not reach the target pressure value), controlling the frequency of the actuator to decrease according to a pre-provided functional relationship, and the pre-provided functional relationship satisfies that the difference value corresponding to each actual pressure value corresponds one-to-one with the frequency of the actuator.

[0044] Optionally, when the first actual pressure value and the second actual pressure value are adjacent to each other and the pressure change amount is greater than zero, as the difference value between the actual pressure value and the target pressure value decreases, the frequency of the actuator decreases according to a pre-provided functional relationship. Specifically, the actual pressure value in the process chamber measured in real time is compared with the pre-provided target pressure value, and based on the difference between the two real-time difference values, the change adjustment of the actuator frequency is performed. Specifically, as the difference value between the real-time pressure detection value and the pressure setting continuously decreases, the actuator frequency continuously decreases. In the process from the measured actual pressure P1 to the pre-provided target pressure Pn, ΔP1 = Pn - P1, and ΔP1 corresponds to one actuator frequency. For the actual pressure P2, ΔP2 = Pn - P2, which corresponds to another actuator frequency. Among them, P1 and P2 are two adjacent pressure values measured in real time, and until the difference value ΔP = 0, each pressure value corresponds to one frequency and is a linear change. The frequency change of the actuator changes the moving speed of the pressure regulating valve (specifically referring to the moving speed of the valve caused by the generator).

[0045] The pressure control method automatically realizes stepwise and refined frequency conversion together with the pressure set point (target pressure value). That is, in the closed-loop control process, according to the difference value between the actual pressure and the set pressure, and according to the set threshold value of the pressure change amount, the generator frequency conversion control is performed. The closer to the set point, the slower the operating speed of the generator, realizing the stabilization of the pressure, effectively avoiding pressure overshoot in the pressure control process, and improving the process effect.

[0046] It should be noted that the control method of this embodiment is similarly applicable to other pressure control methods that perform closed-loop control based on the difference value.

[0047] In this embodiment, the pressure regulating valve may be a piston valve, a butterfly valve, a needle valve, a ball valve, etc.

[0048] Hereinafter, the chamber pressure control method of this embodiment will be further explained by taking the piston valve as an example.

[0049] In the control process of the piston valve, the adjustment of the position of the piston valve is basically carried out by the aerodynamic bearing and force balance. When a certain threshold value is reached, the generator drive does not function, and the piston valve is mechanically adjusted by the automatic expansion and contraction of the spring, enabling faster and more stable pressure control.

[0050] Taking the piston valve as an example, in the pressure control system, especially for the chamber pressure response with a large volume, there is often a certain hysteresis. In order to make the control effect better, based on the frequency conversion control, the buffer hysteresis compensation control is superimposed again (adjusted purely by mechanical elasticity), which can bring a better control effect.

[0051] As shown in Figure 2, the horizontal coordinate in the figure is time, the vertical coordinate is pressure, and P1 is a set target pressure value. In the process of detecting that the actual pressure in the chamber approaches the pressure setting, the actuator (motor) frequency decreases as the difference value between the detected actual pressure value in the process chamber and the set target pressure value shrinks. The gradual increase from t1 to tn shown in Figure 2 means the decrease in the frequency of the actuator.

[0052] The initial frequency F of the actuator 1 is a fixed maximum value (the maximum value at which the execution system does not generate resonance), and this value is subject to the limitations of the pressure system, among which, F i+1 =K×F i where Fi is the current frequency of the actuator, F i+1 is the next frequency of the actuator, the possible values of K are 0 to 1, i = 1, 2, 3,..., n, and F 1is the initial frequency. The K value can be set according to the actual demand. For example, K = 0.1. When triggering the frequency conversion condition, for example, according to a certain ratio of the difference between the measured actual pressure value and the set target pressure value (for example, 5%, that is, the pressure difference for the next frequency conversion needs to change by more than 5%), the degree of frequency conversion can be adjusted according to the actual situation. For example, it can be changed to 10% of the previous frequency each time and can decrease step by step.

[0053] In the reaction chamber pressure control system, if the gas flow rate continuously decreases or increases step by step within a specified time, it will cause fluctuations in the chamber pressure. If there is a deviation between the actual pressure and the set pressure in the chamber, the actuator will perform a frequency conversion operation. As the difference value between the actual pressure value in the chamber and the set target pressure value decreases step by step, the moving speed of the pressure regulating valve will also gradually slow down, thus avoiding the problem of pressure overshoot and minimizing the impact of pressure fluctuations on the process.

[0054] From the above, the chamber pressure control method of the present invention can reduce the phenomenon of pressure overshoot caused by pressure changes or flow rate changes, make the response time of pressure control faster, and the pressure control more stable. In addition, the chamber pressure control method provided by the present invention is not limited to use in the semiconductor field and can also be applied to other pressure control fields such as the solar power generation field.

[0055] Example 2 As shown in FIG. 3, the chamber pressure control device includes a pressure collector 1, a pressure controller 2, and an actuator 3.

[0056] The pressure collector 1 is used to collect the actual pressure value in the process chamber in real time.

[0057] The pressure controller 2 is used to execute the chamber pressure control method of Example 1.

[0058] The actuator 3 is used to control the opening degree change of the pressure regulating valve 4 based on the frequency output by the pressure controller 2.

[0059] In this embodiment, it further includes a parameter setting module 5 used to provide functions such as calculating the target pressure value of the chamber and the actuator frequency.

[0060] In this embodiment, the actuator 3 is a generator that controls the opening degree change of the pressure regulating valve 4, and the frequency of the actuator 3 is the rotational frequency of the generator.

[0061] In this embodiment, the pressure regulating valve 4 is a piston valve, a butterfly valve, a needle valve, or a ball valve.

[0062] Preferably, the pressure regulating valve is provided with an elastic expansion and contraction member used to adjust the opening degree by acting as a pressure regulating valve. For example, it is a piston valve with a spring. During the control process of the piston valve, the adjustment of the position of the piston valve is basically carried out by an aerodynamic bearing and force balance. When a certain threshold value is reached, the drive of the generator does not function, and the piston valve is mechanically adjusted by the spring for automatic expansion and contraction, enabling faster and more stable pressure control.

[0063] When there is a deviation between the actual pressure and the set pressure in the chamber of the chamber pressure control device of this embodiment, the pressure controller performs closed-loop control using the chamber pressure control method of Embodiment 1, and the control actuator 3 performs a frequency conversion operation. As the difference value between the actual pressure value and the set target pressure value in the process chamber decreases and the frequency change decreases step by step, the moving speed of the pressure regulating valve also gradually slows down, thus avoiding the problem of pressure overshoot and minimizing the impact of pressure fluctuations on the process.

[0064] Embodiment 3 As shown in FIG. 4, the semiconductor process device includes a process chamber 6 and further includes the chamber pressure control device of Embodiment 2.

[0065] In this embodiment, one end of the process chamber 6 is connected to the inlet pipeline 8, and the other end is connected to the exhaust pipeline 9. A pressure collector 1, a pressure regulating valve 4, and a vacuum extraction device 7 are provided in the exhaust pipeline 9. The pressure regulating valve 4 is connected to the actuator 3, and the pressure collector 1, the actuator 3, and the parameter setting module 5 are respectively connected to the pressure controller 2.

[0066] By adopting the chamber pressure control device of Embodiment 2, the semiconductor device of this embodiment can achieve rapid and stable control of the chamber pressure and avoid the problem of pressure overshoot, thereby improving the process quality and yield.

[0067] As described above, various embodiments of the present invention have been described. However, the foregoing description is exemplary and not exhaustive, and is not limited to each disclosed embodiment. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of each embodiment described above.

Claims

1. A pressure control method applied to a process chamber of a semiconductor process device, wherein a pressure regulating valve for adjusting the pressure in the process chamber is provided on the gas pipeline of the process chamber, comprising: acquiring the actual pressure value in the process chamber in real time; calculating the amount of pressure change of the actual pressure value; comparing the amount of pressure change with a preset value provided in advance, and when the amount of pressure change is less than or equal to the preset value, controlling the actuator of the pressure regulating valve to maintain the current frequency, controlling the opening degree change of the pressure regulating valve based on this frequency, and when the amount of pressure change is greater than the preset value, controlling the frequency of the actuator to decrease according to a preset functional relationship, and controlling the opening degree change of the pressure regulating valve based on this frequency. A pressure control method characterized by comprising the above.

2. Calculating the amount of pressure change of the actual pressure value includes: calculating a first difference value between a first actual pressure value in the process chamber and a target pressure value acquired at a first time; calculating a second difference value between a second actual pressure value in the process chamber and the target pressure value acquired at a second time; calculating a ratio between the difference value between the first difference value and the second difference value and the maximum difference value between the initial actual pressure value and the target pressure value in the process chamber as the amount of pressure change. The pressure control method according to claim 1, characterized by comprising the above.

3. Calculating the amount of pressure change of the actual pressure value includes: calculating a first difference value between a first actual pressure value in the process chamber and the target pressure value acquired at a first time; calculating a second difference value between a second actual pressure value in the process chamber and the target pressure value acquired at a second time; calculating a ratio between the difference value between the first difference value and the second difference value and the first difference value as the amount of pressure change. The pressure control method according to claim 1, characterized by comprising the above.

4. Controlling the frequency of the actuator to decrease according to a preset functional relationship includes: calculating the difference value between each acquired actual pressure value and the target pressure value; When the difference value is greater than zero, control the frequency of the actuator to decrease according to the pre-provided functional relationship, and the pre-provided functional relationship satisfies that the difference value corresponding to each of the actual pressure values corresponds one-to-one with the frequency of the actuator. The pressure control method according to any one of claims 1 to 3 is characterized by including this.

5. The pre-provided functional relationship is F i+1 = K × F i where F i is the current frequency of the actuator, F i+1 is the next frequency of the actuator, the possible values of K are 0 to 1, i = 1, 2, 3, …, n, and F 1 is the initial frequency of the actuator, and the initial frequency is the maximum frequency at which resonance of the actuator does not occur. The pressure control method according to any one of claims 1 to 3, characterized in that.

6. Controlling the change in the opening degree of the pressure regulating valve based on the frequency includes Based on the obtained actual pressure value and a pre-provided target pressure value, controlling the change in the opening degree of the pressure regulating valve using a PID closed-loop control method. The pressure control method according to claim 5 is characterized by including this.

7. The actual pressure value is the absolute pressure value inside the process chamber, or Alternatively, the actual pressure value is the relative value between the internal pressure of the process chamber and the atmospheric pressure. The pressure control method according to claim 1 is characterized by this.

8. Comprising a pressure collector, a pressure controller, and an actuator, The pressure collector is used to collect the actual pressure value inside the process chamber in real time, The pressure controller is used to execute the pressure control method according to any one of claims 1 to 7, The actuator is used to control the change in the opening degree of the pressure regulating valve based on the frequency output by the pressure controller. A chamber pressure control device is characterized by this.

9. The actuator is a generator that controls the change in the opening degree of the pressure regulating valve, and the frequency of the actuator is the rotational frequency of the generator. The chamber pressure control device according to claim 8 is characterized by this.

10. The pressure regulating valve is provided with an elastic expansion and contraction member that can be used to adjust the opening degree of the pressure regulating valve. The chamber pressure control device according to claim 8 is characterized by this.

11. A semiconductor process device comprising a process chamber and a pressure regulating valve provided on the gas pipeline of the process chamber, Further comprising the chamber pressure control device according to any one of claims 8 to 10. A semiconductor process device is characterized by this.

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