Dew point control method and related device

Abstract

The embodiment of the invention provides a dew point control method, which comprises the following steps of: after an actual dew point of input gas is obtained, when the actual dew point is smaller than an alarm dew point and larger than a reference dew point, inquiring a fuzzy rule based on a deviation parameter, determining a value range of an adjusting parameter, and determining the value range of the adjusting parameter based on the value range of the adjusting parameter. The actual value of the adjusting parameter is determined, and the pressure controller is adjusted based on the actual value of the adjusting parameter to adjust the air pressure of the input gas, so that the actual dew point approaches the reference dew point. Thus, in the process of adjusting the pressure of the input gas by adjusting the pressure controller, the value range of the adjusting parameters is determined through the fuzzy rule, the problem that overshoot or oscillation is likely to occur in the conventional control technology is avoided, the actual dew point of the gas is controlled to be close to the reference dew point, and the control accuracy is improved. And the condensation phenomenon caused by the fact that the actual dew point exceeds the alarm dew point is avoided.

Description

Technical Field

[0001] This specification relates to the field of semiconductor technology, specifically to dew point control technology in the field of semiconductor technology, and more specifically to a dew point control method and related apparatus. Background Technology

[0002] In the field of semiconductor technology, various gases participate in semiconductor manufacturing processes, either directly in reactions, as carrier gases, or as cleaning and etching gases. Nitrogen, for example, is one of the most important gases in semiconductor manufacturing processes, often used as a carrier gas or purging gas for special applications. The nitrogen and other gases supplied by the gas supply system generally need to meet conditions of high cleanliness, high purity, and high dryness. If condensation occurs during the process, it may negatively impact the process results or damage semiconductor equipment. Therefore, monitoring and controlling the gas dew point is of great significance. Summary of the Invention

[0003] This specification provides a dew point control method and related apparatus to control the actual dew point of a gas near a reference dew point, thereby preventing condensation caused by the actual dew point exceeding the alarm dew point.

[0004] To achieve the above technical objectives, the embodiments of this specification provide the following technical solutions:

[0005] Firstly, one embodiment of this specification provides a dew point control method applied to a dew point control device. The dew point control device includes: a first gas path and an output gas path. The first gas path receives input gas and outputs it through the output gas path. A pressure controller is provided in the output gas path. The dew point control method includes:

[0006] Obtain the actual dew point of the input gas;

[0007] When the actual dew point is less than the alarm dew point but greater than the reference dew point, a fuzzy rule is used to determine the range of values ​​for the adjustment parameter based on the deviation parameter. The fuzzy rule includes the correspondence between the range of values ​​for the deviation parameter and the range of values ​​for the adjustment parameter. The deviation parameter describes the magnitude of the difference between the actual dew point and the alarm dew point, and / or the trend of the difference between the actual dew point and the alarm dew point. The reference dew point is less than the alarm dew point.

[0008] Based on the range of the adjustment parameter, the actual value of the adjustment parameter is determined, and the pressure controller is adjusted based on the actual value of the adjustment parameter to adjust the pressure of the input gas, so that the actual dew point approaches the reference dew point.

[0009] Secondly, one embodiment of this specification provides a dew point control device, including: a first gas path, an output gas path, and a controller, wherein the first gas path is used to receive input gas and output it through the output gas path, and a pressure controller is provided in the output gas path;

[0010] The controller is configured to: acquire the actual dew point of the input gas;

[0011] When the actual dew point is less than the alarm dew point but greater than the reference dew point, a fuzzy rule is used to determine the range of values ​​for the adjustment parameter based on the deviation parameter. The fuzzy rule includes the correspondence between the range of values ​​for the deviation parameter and the range of values ​​for the adjustment parameter. The deviation parameter describes the magnitude of the difference between the actual dew point and the alarm dew point, and / or the trend of the difference between the actual dew point and the alarm dew point. The reference dew point is less than the alarm dew point.

[0012] Based on the range of the adjustment parameter, the actual value of the adjustment parameter is determined, and the pressure controller is adjusted based on the actual value of the adjustment parameter to adjust the pressure of the input gas, so that the actual dew point approaches the reference dew point.

[0013] Thirdly, one embodiment of this specification also provides a semiconductor process apparatus, including: a process chamber and a dew point control device, wherein the dew point control device includes the dew point control device as described in any of the preceding claims.

[0014] Fourthly, one embodiment of this specification also provides a computing device including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the dew point control method as described above.

[0015] Fifthly, one embodiment of this specification also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the dew point control method as described above.

[0016] Sixthly, embodiments of this specification provide a computer program product or computer program, the computer program product including a computer program stored in a computer-readable storage medium; the processor of the computer device reads the computer program from the computer-readable storage medium, and when the processor executes the computer program, it implements the steps of the dew point control method described above.

[0017] As can be seen from the above technical solution, the dew point control method provided in this specification, after obtaining the actual dew point of the input gas, determines the range of adjustment parameters based on fuzzy rules when the actual dew point is less than the alarm dew point but greater than the reference dew point. Based on the range of adjustment parameters, the actual value of the adjustment parameters is determined, and the pressure controller is adjusted based on the actual value of the adjustment parameters to regulate the gas pressure of the input gas, thereby bringing the actual dew point closer to the reference dew point. Thus, in the process of adjusting the gas pressure of the input gas by adjusting the pressure controller, the range of adjustment parameters is determined by fuzzy rules, avoiding the problems of overshoot or oscillation that easily occur in conventional control techniques. This achieves the goal of controlling the actual dew point of the gas near the reference dew point and preventing condensation caused by the actual dew point exceeding the alarm dew point. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments or prior art of this specification, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this specification. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of a dew point control device in related technologies.

[0020] Figure 2 A flowchart illustrating a dew point control method provided for one embodiment of this specification;

[0021] Figure 3 A schematic diagram of a dew point control device provided for one embodiment of this specification;

[0022] Figure 4 A hardware block diagram of a controller adjusting PID parameters in a PID controller is provided as one embodiment of this specification;

[0023] Figure 5 A block diagram illustrating the principle of a controller adjusting PID parameters in a PID controller, provided as one embodiment of this specification;

[0024] Figure 6 This is a schematic diagram of the structure of a computing device provided for one embodiment of this specification. Detailed Implementation

[0025] Unless otherwise defined, the technical or scientific terms used in the embodiments of this specification shall have the ordinary meaning understood by one of ordinary skill in the art to which this specification pertains. The terms "first," "second," and similar terms used in the embodiments of this specification do not indicate any order, quantity, or importance, but are merely used to avoid confusion of constituent elements.

[0026] Unless the context otherwise requires, throughout this specification, "a plurality of" means "at least two," and "including" is interpreted as open-ended or encompassing, that is, "including, but not limited to." In the description of this specification, terms such as "one embodiment," "some embodiments," "exemplary embodiment," "example," "specific example," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this specification. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example.

[0027] The technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this specification, and not all embodiments. Based on the embodiments in this specification, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this specification.

[0028] Overview

[0029] like Figure 1 As shown, Figure 1 This diagram illustrates a structural schematic of a section in a semiconductor process apparatus that controls the flow of input gas into the process chamber. Figure 1 In this system, the carrier gas enters from one side of the hand valve 01. When the hand valve 01 is open, the carrier gas (hereinafter referred to as the input gas) is transmitted through the gas path to the branch where the MFC (Mass Flow Controller) 01 and EPC (Electronic Pressure Controller) 01 are located. The pressure gauge can detect the gas pressure of the input gas in the gas path. The controller can adjust the gas pressure, flow rate, and other parameters of the input gas in the gas path by adjusting EPC01. The MFC 01 is adjusted in conjunction with EPC01 to adjust the gas pressure and other parameters of the input gas. The 5 / 2 valve is a five-position two-way valve. Special gases output from special gas sources such as MO (Molybdenum) source 01 are introduced into the input gas through the five-position two-way valve. By controlling the state of the 5 / 2 valve, the input gas carrying the special gas is transmitted to the process chamber for chemical reaction through Run01, or purged or discharged with excess gas through the Vent01 pipeline.

[0030] In the semiconductor manufacturing process, if the dew point of the gas is too high, it can cause water in the gas to condense on the gas path surface and react violently with the MO source, generating other byproducts. Furthermore, it may cause moisture contamination of the wafer, leading to swelling and other quality defects. Therefore, it is necessary to ensure that the dew point of the gas is sufficiently low during its use. Refer to Table 1, which shows the relationship between the dew point, volume ratio, and absolute water content of the gas in the atmospheric environment.

[0031] Table 1. Relationship between volume ratio and absolute water content of atmospheric dew point.

[0032]

[0033] The volume ratio in Table 1 refers to the volume ratio of water vapor in the gas. Volume ratio and absolute water content express the proportion of water in the gas in different ways. Table 1 shows that, under the same gas pressure conditions, the higher the water content in the gas, the higher the dew point (or dew point temperature). For example, when the absolute water content in the gas is 0.09499 g / m³... 3 At this temperature, the dew point is -40℃, meaning that when the gas temperature is below -40℃, water vapor in the gas will condense into liquid, resulting in condensation. When the absolute water content in the gas is higher than 0.2811 g / m³, condensation will occur. 3 When the dew point rises to -30℃, meaning that when the gas temperature is below -30℃, the water vapor in the gas will condense into liquid. Therefore, keeping the gas dry is an effective way to lower the dew point.

[0034] However, during the production process of semiconductor process equipment, the moisture content of the gas supplied to the semiconductor process equipment is usually relatively fixed. With changes in the temperature, air pressure, and other factors of the operating environment, the dew point of the gas may not meet the actual requirements. For example, assuming the working environment temperature of the input gas is -10°C, the dew point of the input gas must not be higher than -10°C. If the dew point of the input gas is higher than -10°C, the water vapor in the input gas may condense because the working environment temperature is lower than the dew point of the input gas. This may have an adverse effect on the process effect and may also damage the gas path of the semiconductor process equipment.

[0035] The inventors discovered through research that the dew point of the input gas can be adjusted by regulating the gas pressure, keeping it below the alarm dew point. This prevents condensation caused by the actual dew point being lower than the working environment temperature. Furthermore, to avoid overshoot during gas pressure adjustment, fuzzy rules are used to determine the range of adjustment parameters when adjusting the input gas pressure via a pressure controller. This avoids overshoot or oscillation problems that are common in conventional control techniques, achieving the goal of controlling the actual dew point of the gas near the reference dew point and preventing condensation caused by the actual dew point exceeding the alarm dew point.

[0036] Based on the above concept, this specification provides a dew point control method. The dew point control method provided by this specification will be described exemplarily below with reference to the accompanying drawings.

[0037] Exemplary methods

[0038] This specification provides a dew point control method, applicable to, for example... Figure 3 The dew point control device shown includes a first gas path 10 and an output gas path 20. The first gas path 10 receives input gas and outputs it through the output gas path 20. A pressure controller 21 is provided in the output gas path 20. Figure 2 As shown, the dew point control method includes:

[0039] S201: Obtain the actual dew point of the input gas;

[0040] S202: When the actual dew point is less than the alarm dew point but greater than the reference dew point, a fuzzy rule is queried based on the deviation parameter to determine the value range of the adjustment parameter; the fuzzy rule includes the correspondence between the value range of the deviation parameter and the value range of the adjustment parameter, the deviation parameter is used to describe the magnitude of the difference between the actual dew point and the alarm dew point, and / or the trend of the change of the difference between the actual dew point and the alarm dew point; the reference dew point is less than the alarm dew point;

[0041] S203: Based on the range of the adjustment parameter, determine the actual value of the adjustment parameter, and adjust the pressure controller 21 based on the actual value of the adjustment parameter to adjust the gas pressure of the input gas, so that the actual dew point approaches the reference dew point.

[0042] exist Figure 3In the dew point control device shown, in addition to the first gas path 10 and the output gas path 20, some embodiments may also include an exhaust gas path 30. The opening degree of the output gas path 20 and the exhaust gas path 30 can be adjusted by controlling the opening degree of the seventh valve 40. The pressure controller 21 installed in the output gas path 20 can be an electronic pressure controller 21 (EPC). The controller of the semiconductor process equipment can adjust the gas pressure in the dew point control device by adjusting the pressure controller 21. A mass flow controller 31 may be installed in the exhaust gas path 30. The mass flow controller 31 can work with the pressure controller 21 to adjust the gas pressure. In addition, the mass flow controller 31 can adjust the mass flow rate of the gas in the exhaust gas path 30. In some embodiments, the dew point control device may also include components such as a pressure gauge 60 and a manual valve 50. The pressure gauge 60 is used to detect the gas pressure, and the manual valve 50 can be used to manually adjust the opening and closing state of the first gas path 10.

[0043] In step S201, the actual dew point of the input gas can be directly measured by a specific detection device 143 (e.g., a dew point meter), or it can be calculated by a combination of some detection devices 143 (e.g., a combination of a humidity sensor, a pressure gauge, and a thermometer). This specification does not limit this.

[0044] The alarm dew point can be determined based on at least one of the following parameters: the theoretical operating ambient temperature of the input gas, its absolute water content, and its volume ratio. The alarm dew point characterizes the dew point at which condensation is highly probable when the temperature of the input gas is below a certain dew point. For example, assuming the theoretical operating ambient temperature of a certain input gas is -10℃, the alarm dew point needs to be below -10℃. This is because the input gas typically operates at -10℃. If the alarm dew point is above -10℃ (e.g., 0℃), it indicates that the input gas will condense in the normal operating environment, causing it to fail to meet normal operating requirements.

[0045] The reference dew point can be a dew point adjustment threshold set based on the alarm dew point. If the actual dew point is greater than the reference dew point, it is considered that the actual dew point is too high and needs to be controlled. Otherwise, it may further exceed the alarm dew point, causing condensation to occur.

[0046] Regarding the dew point of a gas, with a constant water content, the dew point increases with increasing gas pressure, and vice versa. Therefore, the pressure of the input gas can be controlled by controlling the pressure controller 21 in the output gas path 20, thereby adjusting the actual dew point to approach the reference dew point and move it away from the alarm dew point, thus avoiding condensation caused by the actual dew point being higher than the alarm dew point. However, in traditional closed-loop control techniques (such as PID control), if the adjustment parameters of the pressure controller 21 are not properly determined, overshoot may occur (i.e., the actual dew point may briefly exceed the alarm dew point, leading to condensation risk). To address this issue, in this embodiment, after obtaining the actual dew point of the input gas, the dew point control method, when the actual dew point is less than the alarm dew point but greater than the reference dew point, uses fuzzy rules based on the deviation parameter to determine the range of adjustment parameters. Based on this range, the actual value of the adjustment parameters is determined, and the pressure controller 21 is adjusted based on the actual value to regulate the pressure of the input gas, thereby bringing the actual dew point closer to the reference dew point. Thus, during the process of adjusting the input gas pressure by adjusting the pressure controller 21, the range of adjustment parameters is determined using fuzzy rules, avoiding the overshoot or oscillation problems common in conventional control techniques. This achieves the goal of controlling the actual dew point of the gas near the reference dew point, preventing condensation caused by the actual dew point exceeding the alarm dew point.

[0047] Understandably, when the actual dew point is higher than or lower than the reference dew point, the actual dew point of the input gas can be considered relatively safe, with a very low probability of condensation, and no adjustment of the pressure controller 21 is required. When the actual dew point is higher than the alarm dew point and this phenomenon persists for a certain period of time, it is considered that the actual dew point cannot be effectively reduced by the dew point control method, and an alarm message can be issued. This alarm message is used to prompt maintenance personnel to investigate the location of leaks in the semiconductor process equipment.

[0048] In one implementation, to improve the actual dew point control effect, reference is still made. Figure 3 The dew point control device further includes: a drying branch 13, which is connected in parallel with the first target gas path 11. The first target gas path 11 includes a portion of the gas path in the first gas path 10. A drying device 133 is provided in the drying gas path.

[0049] The dew point control method further includes:

[0050] When the actual dew point is less than the alarm dew point but greater than the reference dew point, the first target gas path 11 is bypassed by the drying branch 13 so that the input gas can be dried by the drying device 133.

[0051] By drying the input gas using the drying device 133, the water content in the input gas can be effectively reduced. As mentioned earlier, reducing the water content in the gas can effectively lower the dew point of the input gas. Therefore, in this embodiment, the reduction of the water content in the input gas by the drying device 133, combined with the pressure regulation of the input gas by the pressure controller 21, achieves the goal of lowering the actual dew point.

[0052] The drying equipment 133 includes, but is not limited to, a membrane dryer.

[0053] In an optional embodiment, a first valve 111 is provided in the first target gas path 11, and a second valve 131 and a third valve 132 are provided in the drying gas path. The second valve 131 and the third valve 132 are respectively located on both sides of the drying device 133. The first valve 111, the second valve 131, and the third valve 132 are all pneumatic valves whose opening degree can be controlled by a controller. In this embodiment, by closing the first valve 111 and opening the second valve 131 and the third valve 132, the input gas can flow through the drying branch 13, thereby achieving the purpose of bypassing the first target gas path 11 using the drying branch 13, and simultaneously achieving the purpose of drying the input gas using the drying device 133.

[0054] In an alternative implementation, a method for detecting the actual dew point is provided, still referring to... Figure 3 The dew point control device further includes: a detection gas path, which is connected in parallel with the second target gas path 12. The second target gas path 12 includes a portion of the gas path in the first gas path 10. A detection device 143 is provided in the detection gas path.

[0055] The process of obtaining the actual dew point of the input gas includes:

[0056] The second target gas path 12 is bypassed by the detection gas path so that the actual dew point of the input gas can be obtained by the detection device 143.

[0057] In an optional embodiment, a fourth valve 121 is provided in the second target gas path 12, and a fifth valve 141 and a sixth valve 142 are provided in the detection branch 14. The fifth valve 141 and the sixth valve 142 are respectively located on both sides of the detection device 143. The fourth valve 121, the fifth valve 141, and the sixth valve 142 can all be pneumatic valves that can be controlled by a controller. In use, by closing the fourth valve 121 and opening the fifth valve 141 and the sixth valve 142, the second target gas path 12 can be bypassed using the detection branch 14, thereby enabling the detection device 143 to detect the actual dew point of the input gas. The detection device 143 includes, but is not limited to, a dew point meter.

[0058] In an optional implementation, when the semiconductor process equipment is in maintenance mode or the semiconductor process equipment is powered off, the dew point control method further includes:

[0059] Open the first valve 111 and the fourth valve 121, and close the second valve 131, the third valve 132, the fifth valve 141 and the sixth valve 142 to ensure that the drying branch 13, the detection branch 14, the drying equipment 133 and the detection equipment 143 are not contaminated by other external gases or impurities in the maintenance mode or power-off state.

[0060] In an optional embodiment of this specification, a feasible implementation of a deviation parameter is provided, the deviation parameter including: a dew point difference, and / or, the derivative of the dew point difference; the dew point difference includes the difference between the actual dew point and the reference dew point.

[0061] In one optional implementation, the deviation parameter includes a dew point difference, and the adjustment parameter includes proportional, integral, and derivative parameters;

[0062] The fuzzy rules include:

[0063] When the absolute value of the dew point difference is within the first difference range, the corresponding proportional value range is within the first proportional range, the corresponding derivative value range is within the second derivative range, and the corresponding integral value approaches 0. In this case, a larger proportional value can speed up the system response time, while a smaller derivative value can prevent the dew point difference from exceeding the system's control range when performing PID control. In addition, the integral value approaching 0 can prevent the EPC pressure setpoint from overshooting significantly.

[0064] When the absolute value of the dew point difference is within the second difference range, the corresponding proportional value range is within the second proportional range, the corresponding integral value range is within the third integral range, and the corresponding derivative value range is within the third derivative range. In this case, a smaller proportional parameter can prevent the system from changing too quickly, and appropriately selected integral and derivative values ​​can ensure the system's response speed.

[0065] When the absolute value of the dew point difference is within the third difference range, the corresponding proportional value range is within the second proportional range, and the corresponding integral value range is within the second integral range; in this case, smaller proportional and integral values ​​can enable the system to maintain good steady-state performance.

[0066] The values ​​in the first difference range are all greater than the values ​​in the second difference range, and the values ​​in the second difference range are all greater than the values ​​in the third difference range;

[0067] The proportion values ​​in the third proportion range are all greater than the proportion values ​​in the second proportion range; the proportion values ​​in the first proportion range are all greater than the proportion values ​​in the third proportion range.

[0068] The integral values ​​in the third integration range are all greater than the integral values ​​in the second integration range; the integral values ​​in the first integration range are all greater than the integral values ​​in the third integration range.

[0069] The differential values ​​in the third differential range are all greater than the differential values ​​in the second differential range; the differential values ​​in the first differential range are all greater than the differential values ​​in the third differential range.

[0070] In another optional embodiment, the deviation parameter includes the dew point difference Tk and the derivative of the dew point difference (specifically, the first derivative) dTk. In this way, when determining the adjustment parameter, not only the difference between the actual dew point and the reference dew point is considered, but also the rate of change of this difference is considered, which is beneficial to comprehensively consider the actual dew point situation and more accurately determine the range of values ​​for the adjustment parameter.

[0071] In an optional implementation, taking PID (Proportional-Integral-Derivative) regulation as an example, the deviation parameter includes: the dew point difference and the derivative of the dew point difference; the regulation parameter includes proportional, integral and derivative.

[0072] The fuzzy rules include:

[0073] When the absolute value of the dew point difference is within the first difference range, and the derivative of the dew point difference is greater than 0, the corresponding proportional value range is within the first proportional range, the corresponding integral value approaches 0, and the corresponding differential value range is within the second differential range.

[0074] When the absolute value of the dew point difference is within the first difference range, and the derivative of the dew point difference is less than 0, the corresponding proportional value range is within the third proportional range, the corresponding integral value approaches 0, and the corresponding differential value range is within the second differential range; the proportional values ​​in the first proportional range are all greater than the proportional values ​​in the third proportional range.

[0075] When the absolute value of the dew point difference is within the second difference range, and the derivative of the dew point difference is less than 0, the corresponding proportional value range is within the second proportional range, the corresponding integral value range is within the third integral range, and the corresponding differential value range is within the third differential range; the proportional values ​​in the third proportional range are all greater than the proportional values ​​in the second proportional range; the differential values ​​in the third differential range are all greater than the differential values ​​in the second differential range.

[0076] When the absolute value of the dew point difference is within the second difference range, and the derivative of the dew point difference is greater than 0, the corresponding proportional value range is within the third proportional range, the corresponding integral value range is within the third integral range, and the corresponding differential value range is within the third differential range.

[0077] When the absolute value of the dew point difference is within the third difference range, and the absolute value of the derivative of the dew point difference is within the third difference range, the corresponding proportional value range is within the second proportional range, the corresponding integral value range is within the second integral range, and the corresponding differential value range is within the first differential range; the differential values ​​in the first differential range are all greater than the differential values ​​in the third differential range; the integral values ​​in the third integral range are all greater than the integral values ​​in the second integral range.

[0078] When the absolute value of the dew point difference is within the third difference range, and the absolute value of the derivative of the dew point difference is within the first difference range, the corresponding proportional value range is within the second proportional range, the corresponding integral value range is within the second integral range, and the corresponding differential value range is within the second differential range; all values ​​in the first difference range are greater than all values ​​in the second difference range, and all values ​​in the second difference range are greater than all values ​​in the third difference range.

[0079] refer to Figure 4 and Figure 5 , Figure 4 and Figure 5 This specification illustrates the hardware and principle block diagram of the controller adjusting the PID parameters in the PID controller according to the embodiment of the present specification. The controller (e.g., a PLC (Programmable Logic Controller) in the lower-level machine of a semiconductor process equipment) reads the actual dew point T(t) of the input gas detected by the detection device 143 from the PID controller, and calculates the difference between the actual dew point T(t) and the reference dew point T1 through a subtractor or other arithmetic elements to obtain the dew point difference value Tk. The dew point difference value Tk is used to obtain the derivative dTk of the dew point difference value through a differentiator or other arithmetic elements. Tk and dTk are used as inputs for fuzzy rules to obtain the PID value ranges Kp*, KI*, and Kd* corresponding to Tk and dTk. Finally, based on fuzzy calculation, the final PID parameters (i.e., adjustment parameters) are determined from the PID value ranges and output to the PID controller. The PID controller outputs control parameters Ps(t) based on the adjustment parameters. The control parameters Ps(t) are used to adjust the set pressure value P(t) of the control pressure controller 21. The pressure controller 21 controls the gas pressure of the input gas according to the set pressure value P(t).

[0080] In this embodiment, when |Tk| is large, i.e., |Tk| is within the first difference range (this first difference range can be, for example, |Tk|>(T0-T1)*0.7), and when the actual dew point T(t) is far from the reference dew point T1, i.e., dTk>0, a relatively large Kp (i.e., Kp is within the first proportional range) and a relatively small Kd (i.e., Kd is within the second derivative range) can be selected. A larger Kp can speed up the system's response time, while a smaller Kd can prevent |Tk| from exceeding the system's control range when performing PID control. In addition, to avoid a large overshoot in the pressure setpoint of the pressure controller 21, KI can be made to approach 0 (in some embodiments, KI can be equal to 0). That is, when |Tk| is large, it is desirable to obtain a larger absolute value of Kp, a smaller absolute value of Kd, and an absolute value of KI close to 0.

[0081] When |Tk| is large, that is, when |Tk| is in the first difference range (the first difference range can be, for example, |Tk|>(T0-T1)*0.7), and T(t) gradually approaches T1, that is, when dTk<0, the value of Kp can be selected to be moderate (that is, Kp is in the third proportion range), and the value of Kd can be relatively small (that is, Kd is in the second differential range), while KI approaches 0.

[0082] When |Tk| is of a suitable size (i.e., |Tk| is in the second difference range), and T(t) gradually approaches T1, i.e., when dTk < 0, for example, when (T0-T1)*0.3 < |Tk| < (T0-T1)*0.7, a smaller Kp should be chosen (i.e., Kp is in the second proportional range) to prevent the system from changing too quickly. Appropriate KI and Kd should be selected (i.e., KI is in the third integral range and Kd is in the third differential range) to ensure the system's response speed.

[0083] In addition, when |Tk| is of a moderate size (i.e., |Tk| is in the second difference range), and the actual dew point T(t) is far from the reference dew point T1, i.e., dTk>0, the Kp value should be of a moderate size (i.e., Kp is in the third proportional range), and moderate KI and Kd should be selected (i.e., KI is in the third integral range and Kd is in the third differential range).

[0084] When |Tk| is small (i.e., the range of |Tk| is in the third range), for example, |Tk| < (T0-T1)*0.3, and |dTk| is large (i.e., the absolute value of the derivative of the dew point difference is in the first difference range), smaller Kp and KI can be selected (i.e., the range of Kp is in the second proportional range and the range of KI is in the second integral range) to maintain good steady-state performance of the system. At the same time, the anti-interference performance of the system should also be considered, and the value of Kd can be smaller (i.e., Kd is in the second differential range).

[0085] When |Tk| is small (i.e., the value range of |Tk| is in the third value range), for example, |Tk| < (T0-T1)*0.3, and |dTk| is small (i.e., the absolute value of the derivative of the dew point difference is in the third difference range), smaller Kp and KI can be selected (i.e., Kp is in the second proportional range and the value range of KI is in the second integral range) to maintain good steady-state performance of the system. At the same time, the anti-interference performance of the system should also be considered, and the value of Kd can be larger (i.e., Kd is in the first differential range).

[0086] In summary, based on the rules above, the values ​​of the dew point difference and its derivative can be quantified, for example:

[0087] Tk={-20,-15,-10,-5,0,+5,+10,+15,20};

[0088] dTk={-20,-15,-10,-5,0,+5,+10,+15,+20}

[0089] Seven fuzzy linguistic variables are defined: negative large value (FX), negative moderate value (FM), negative small value (FN), zero (Z), positive small value (ZN), positive moderate value (ZM), and positive large value (ZX). In the controller algorithm, the actual ranges of |dTk| and |Tk| are divided according to these seven fuzzy variables and mapped one-to-one. Based on the above rules, fuzzy rules for the PID parameters are defined, for example: if Tk = fuzzy linguistic variable 1 and dTk = fuzzy linguistic variable 2, then Kp = fuzzy linguistic variable 3.

[0090] To obtain a complete fuzzy control rule, all cases can be listed and the corresponding PID parameters calculated. Taking Kp as an example, if Tk = ZX and dTk = FN, then the dew point difference is a larger positive value and the derivative of the dew point difference is a smaller negative value. In this case, the pressure should change at a moderate rate, then Kp* = FM, and so on.

[0091] After obtaining the value ranges Kp*, KI*, and Kd* of each PID parameter, the specific values ​​Kp, KI, and Kd of the PID parameters are obtained using a self-tuning method. The formula for the PID controller to output the control parameters for controlling the pressure controller 21 based on the PID parameters is as follows:

[0092] Ps(t)=KpT(t)+Ki∫T(t)dt+Kd dT(t) / dt.

[0093] After obtaining the control parameter Ps(t), the set pressure value of the pressure controller 21 is adjusted based on the control parameter.

[0094] Compared with the traditional PID control method, the method for determining the adjustment parameters provided in this embodiment can adaptively adjust the PID parameters, effectively handle nonlinear PID control, and has the advantages of small overshoot and fast response speed.

[0095] Exemplary device

[0096] In one exemplary embodiment of this specification, a dew point control device is also provided, such as... Figure 3 As shown, it includes: a first gas path 10, an output gas path 20 and a controller. The first gas path 10 is used to receive input gas and output it through the output gas path 20. A pressure controller 21 is provided in the output gas path 20.

[0097] The controller is configured to: acquire the actual dew point of the input gas;

[0098] When the actual dew point is less than the alarm dew point but greater than the reference dew point, a fuzzy rule is used to determine the range of values ​​for the adjustment parameter based on the deviation parameter. The fuzzy rule includes the correspondence between the range of values ​​for the deviation parameter and the range of values ​​for the adjustment parameter. The deviation parameter describes the magnitude of the difference between the actual dew point and the alarm dew point, and / or the trend of the difference between the actual dew point and the alarm dew point. The reference dew point is less than the alarm dew point.

[0099] Based on the range of the adjustment parameter, the actual value of the adjustment parameter is determined, and the pressure controller 21 is adjusted based on the actual value of the adjustment parameter to adjust the gas pressure of the input gas, so that the actual dew point approaches the reference dew point.

[0100] Optionally, the dew point control device further includes: a drying branch 13, which is connected in parallel with the first target gas path 11, the first target gas path 11 including a portion of the gas path in the first gas path 10, and a drying device 133 is provided in the drying gas path; a first valve 111 is provided in the first target gas path 11, and a second valve 131 and a third valve 132 are also provided in the drying gas path, the second valve 131 and the third valve 132 being respectively provided on both sides of the drying device 133;

[0101] The controller is also used for:

[0102] When the actual dew point is less than the alarm dew point but greater than the reference dew point, the first valve 111 is closed, and the second valve 131 and the third valve 132 are opened to bypass the first target gas path 11 using the drying branch 13, and the input gas is dried using the drying device 133.

[0103] Optionally, the dew point control device further includes: a detection gas path, which is connected in parallel with the second target gas path 12, the second target gas path 12 including a portion of the gas path in the first gas path 10, and a detection device 143 is provided in the detection gas path; a fourth valve 121 is provided in the second target gas path 12, and a fifth valve 141 and a sixth valve 142 are provided in the detection gas path, the fifth valve 141 and the sixth valve 142 being respectively provided on both sides of the detection device 143;

[0104] The controller acquires the actual dew point of the input gas, specifically for:

[0105] The fourth valve 121 is closed, and the fifth valve 141 and the sixth valve 142 are opened to bypass the second target gas path 12 using the detection gas path, and the actual dew point of the input gas is obtained using the detection device 143.

[0106] Optionally, the controller is further configured to:

[0107] When the semiconductor process equipment is in maintenance mode or the semiconductor process equipment is powered off, the first valve 111 and the fourth valve 121 are opened, and the second valve 131, the third valve 132, the fifth valve 141 and the sixth valve 142 are closed.

[0108] Accordingly, one embodiment of this specification also provides a semiconductor process apparatus, including: a process chamber and a dew point control device as described in any of the above embodiments.

[0109] Accordingly, in one exemplary embodiment of this specification, a dew point control device is also provided, applied to a dew point control equipment. The dew point control equipment includes: a first gas path 10 and an output gas path 20. The first gas path 10 receives input gas and outputs it through the output gas path 20. A pressure controller 21 is provided in the output gas path 20. The dew point control device includes:

[0110] The dew point acquisition module is used to acquire the actual dew point of the input gas;

[0111] The range query module is used to determine the value range of the adjustment parameter based on a fuzzy rule query using a deviation parameter when the actual dew point is less than the alarm dew point but greater than the reference dew point. The fuzzy rule includes the correspondence between the value range of the deviation parameter and the value range of the adjustment parameter. The deviation parameter describes the magnitude of the difference between the actual dew point and the alarm dew point, and / or the trend of change in the difference between the actual dew point and the alarm dew point. The reference dew point is less than the alarm dew point.

[0112] The dew point adjustment module is used to determine the actual value of the adjustment parameter based on the range of the adjustment parameter, and adjust the pressure controller 21 based on the actual value of the adjustment parameter to adjust the gas pressure of the input gas, so that the actual dew point approaches the reference dew point.

[0113] Specific limitations regarding dew point control devices and equipment can be found in the above description of dew point control methods, and will not be repeated here. Each module in the aforementioned dew point control device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in hardware or independently of the processor in a computer device, or stored in software in the memory of a computer device, so that the processor can call and execute the corresponding operations of each module.

[0114] Exemplary computing device

[0115] Another embodiment of this application also proposes a computing device, see [link to relevant documentation] Figure 6 As shown, an exemplary embodiment of this specification also provides a computing device, including: a memory and a processor, the memory storing a computer program, the processor executing the computer program to perform the steps of the dew point control method according to various embodiments of this specification described in the foregoing embodiments.

[0116] The internal structure of the computing device can be as follows: Figure 6 As shown, the computing device includes a processor, memory, network interface, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs in the non-volatile storage medium. The network interface is used to communicate with external terminals via a network connection. When the computer program is executed by the processor, it follows the steps of the dew point control method according to various embodiments of this specification as described in the above embodiments.

[0117] The processor may include the main processor, as well as baseband chips, modems, etc.

[0118] The memory stores a program that executes the technical solution of this invention, and may also store an operating system and other critical business functions. Specifically, the program may include program code, which includes computer operation instructions. More specifically, the memory may include read-only memory (ROM), other types of static storage devices capable of storing static information and instructions, random access memory (RAM), other types of dynamic storage devices capable of storing information and instructions, disk storage, flash memory, etc.

[0119] The processor can be a general-purpose processor, such as a general-purpose central processing unit (CPU), a microprocessor, etc., or an application-specific integrated circuit (ASIC), or one or more integrated circuits used to control the execution of the program of the present invention. It can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an off-the-shelf programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0120] Input devices may include devices that receive data and information input by the user, such as keyboards, mice, cameras, scanners, light pens, voice input devices, touch screens, pedometers, or gravity sensors.

[0121] Output devices may include devices that allow information to be output to the user, such as displays, printers, speakers, etc.

[0122] The communication interface may include any transceiver-like device for communicating with other devices or communication networks, such as Ethernet, Radio Access Network (RAN), Wireless Local Area Network (WLAN), etc.

[0123] The processor executes the program stored in the memory and calls other devices, which can be used to implement the various steps of any of the dew point control methods provided in the above embodiments of this application.

[0124] The computing device may also include a display component and a voice component. The display component may be a liquid crystal display screen or an e-ink display screen. The input device of the computing device may be a touch layer covering the display component, or a button, trackball or touchpad set on the casing of the computing device, or an external keyboard, touchpad or mouse, etc.

[0125] Those skilled in the art will understand that Figure 6The structures shown are merely block diagrams of some structures related to the solutions in this specification and do not constitute a limitation on the computing devices on which the solutions in this specification are applied. Specific computing devices may include more or fewer components than those shown in the figures, or combine certain components, or have different component arrangements.

[0126] Exemplary computer program products and storage media

[0127] In addition to the methods and devices described above, the dew point control methods provided in the embodiments of this specification can also be computer program products, which include computer program instructions that, when executed by a processor, cause the processor to perform the steps in the dew point control methods according to various embodiments of this specification as described in the "Exemplary Methods" section above.

[0128] The computer program product described herein can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments described herein. These programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0129] Furthermore, embodiments of this specification also provide a computer-readable storage medium having a computer program stored thereon, the computer program being executed by a processor of the steps in the dew point control methods according to various embodiments of this specification as described in the "Exemplary Methods" section above.

[0130] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the methods described above. Any references to memory, storage, databases, or other media used in the embodiments provided in this specification can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0131] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0132] The embodiments described above are merely illustrative of several implementation methods outlined in this specification. While the descriptions are specific and detailed, they should not be construed as limiting the scope of the solutions provided in this specification. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this specification, and these all fall within the scope of protection of this specification. Therefore, the scope of protection for this patent should be determined by the appended claims.

Claims

1. A dew point control method characterized by, The application is applied to a dew point control device, which comprises a first gas path for receiving input gas and an output gas path, and a pressure controller is arranged in the output gas path; the dew point control method comprises: acquiring an actual dew point of the input gas; when the actual dew point is less than an alarm dew point and greater than a reference dew point, determining a value range of an adjusting parameter based on a deviation parameter query fuzzy rule, the fuzzy rule comprising a corresponding relationship between a value range of the deviation parameter and a value range of the adjusting parameter, the deviation parameter being used to describe a difference between the actual dew point and the alarm dew point and / or a change trend of the difference, and the reference dew point being less than the alarm dew point; determining an actual value of the adjusting parameter based on the value range of the adjusting parameter, and adjusting the pressure controller based on the actual value of the adjusting parameter to adjust the gas pressure of the input gas, so that the actual dew point approaches the reference dew point.

2. The method of claim 1, wherein, The deviation parameter comprises a dew point difference and / or a derivative of the dew point difference; the dew point difference comprises a difference between the actual dew point and the reference dew point.

3. The method of claim 2, wherein, The deviation parameter comprises a dew point difference; the adjusting parameter comprises a proportion, an integral and a differential; The fuzzy rule comprises: when the absolute value of the dew point difference is in a first difference range, the corresponding proportion value range is in a first proportion range, the corresponding integral value approaches 0, and the corresponding differential value range is in a second differential range; when the absolute value of the dew point difference is in a second difference range, the corresponding proportion value range is in a second proportion range, the corresponding integral value range is in a third integral range, and the corresponding differential value range is in a third differential range; when the absolute value of the dew point difference is in a third difference range, the corresponding proportion value range is in a second proportion range, and the corresponding integral value range is in a second integral range; the values in the first difference range are all greater than the values in the second difference range, and the values in the second difference range are all greater than the values in the third difference range; the proportion values in the third proportion range are all greater than the proportion values in the second proportion range, and the proportion values in the first proportion range are all greater than the proportion values in the third proportion range; the integral values in the third integral range are all greater than the integral values in the second integral range, and the integral values in the first integral range are all greater than the integral values in the third integral range; the differential values in the third differential range are all greater than the differential values in the second differential range, and the differential values in the first differential range are all greater than the differential values in the third differential range.

4. The method of claim 2, wherein, The deviation parameter comprises the dew point difference and the derivative of the dew point difference; The fuzzy rule further comprises: when the absolute value of the dew point difference is in a first difference range and the derivative of the dew point difference is greater than 0, the corresponding proportion value range is in a first proportion range, the corresponding integral value approaches 0, and the corresponding differential value range is in a second differential range. When the absolute value of the dew-point difference is in the first difference range and the derivative of the dew-point difference is less than 0, the corresponding proportional value range is in the third proportional range, the corresponding integral value tends to 0, and the corresponding differential value range is in the second differential range; the proportional values in the first proportional range are all greater than the proportional values in the third proportional range; When the absolute value of the dew-point difference is in the second difference range and the derivative of the dew-point difference is less than 0, the corresponding proportional value range is in the second proportional range, the corresponding integral value range is in the third integral range, and the corresponding differential value range is in the third differential range; the proportional values in the third proportional range are all greater than the proportional values in the second proportional range; the differential values in the third differential range are all greater than the differential values in the second differential range; When the absolute value of the dew-point difference is in the second difference range and the derivative of the dew-point difference is greater than 0, the corresponding proportional value range is in the third proportional range, the corresponding integral value range is in the third integral range, and the corresponding differential value range is in the third differential range; When the absolute value of the dew-point difference is in the third difference range and the absolute value of the derivative of the dew-point difference is in the third difference range, the corresponding proportional value range is in the second proportional range, the corresponding integral value range is in the second integral range, and the corresponding differential value range is in the first differential range; the differential values in the first differential range are all greater than the differential values in the third differential range; the integral values in the third integral range are all greater than the integral values in the second integral range; When the absolute value of the dew-point difference is in the third difference range and the absolute value of the derivative of the dew-point difference is in the first difference range, the corresponding proportional value range is in the second proportional range, the corresponding integral value range is in the second integral range, and the corresponding differential value range is in the second differential range; the values in the first difference range are all greater than the values in the second difference range, and the values in the second difference range are all greater than the values in the third difference range.

5. The method of claim 1, wherein, The dew-point control device further comprises a drying branch, the drying branch is connected in parallel with a first target gas path, the first target gas path comprises part of the first gas path, and a drying device is arranged in the drying gas path; The dew-point control method further comprises: When the actual dew point is less than the alarm dew point and greater than the reference dew point, the first target gas path is bypassed by using the drying branch, so that the input gas is dried by using the drying device.

6. The method of claim 1, wherein, The dew-point control device further comprises a detection gas path, the detection gas path is connected in parallel with a second target gas path, the second target gas path comprises part of the first gas path, and a detection device is arranged in the detection gas path; The actual dew point of the input gas is obtained by: The second target gas path is bypassed by using the detection gas path, so that the actual dew point of the input gas is obtained by using the detection device.

7. A dew point control apparatus characterized by comprising: The dew-point control device further comprises a drying branch, the drying branch is connected in parallel with a first target gas path, the first target gas path comprises part of the first gas path, and a drying device is arranged in the drying gas path; The first gas path is configured to receive input gas and output the input gas through an output gas path, and a pressure controller is arranged in the output gas path; The controller is configured to obtain an actual dew point of the input gas; When the actual dew point is less than an alarm dew point and greater than a reference dew point, a fuzzy rule is queried based on a deviation parameter to determine a value range of an adjustment parameter; The fuzzy rule includes a corresponding relationship between a value range of the deviation parameter and a value range of the adjustment parameter, the deviation parameter is used to describe a difference between the actual dew point and the alarm dew point, and / or a change trend of the difference between the actual dew point and the alarm dew point; The reference dew point is less than the alarm dew point; Based on the value range of the adjustment parameter, an actual value of the adjustment parameter is determined, and the pressure controller is adjusted based on the actual value of the adjustment parameter to adjust the gas pressure of the input gas, so that the actual dew point approaches the reference dew point.

8. The apparatus of claim 7, wherein, Further comprising: A drying branch is connected in parallel with a first target gas path, the first target gas path includes part of the first gas path, and a drying device is arranged in the drying gas path; a first valve is arranged in the first target gas path, and a second valve and a third valve are further arranged in the drying gas path, and the second valve and the third valve are arranged on two sides of the drying device, respectively; The controller is further configured to: When the actual dew point is less than the alarm dew point and greater than the reference dew point, the first valve is closed, and the second valve and the third valve are opened, so that the first target gas path is bypassed by the drying branch, and the input gas is dried by the drying device.

9. The apparatus of claim 8, wherein, The dew point control device further comprises a detection gas path connected in parallel with a second target gas path, the second target gas path includes part of the first gas path, and a detection device is arranged in the detection gas path; a fourth valve is arranged in the second target gas path, and a fifth valve and a sixth valve are arranged in the detection gas path, and the fifth valve and the sixth valve are arranged on two sides of the detection device, respectively; The controller obtains the actual dew point of the input gas, and is specifically configured to: The fourth valve is closed, and the fifth valve and the sixth valve are opened, so that the second target gas path is bypassed by the detection gas path, and the actual dew point of the input gas is obtained by the detection device.

10. The apparatus of claim 9, wherein, The controller is further configured to: When the semiconductor process equipment is in a maintenance mode or the semiconductor process equipment is powered off, the first valve and the fourth valve are opened, and the second valve, the third valve, the fifth valve and the sixth valve are closed.

11. A semiconductor process apparatus, characterized by comprising: Comprising: A process chamber and a dew point control device, the dew point control device comprises the dew point control device as claimed in any one of claims 7 to 10.

12. A computing device, comprising: A memory, a processor and a computer program stored in the memory and executable on the processor, when the processor executes the computer program, the dew point control method as claimed in any one of claims 1 to 6 is implemented.

13. A computer-readable storage medium, characterized in that, The computer readable storage medium stores a computer program, and the computer program is executed by the processor to implement the dew point control method in any one of claims 1-6.

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