Impedance matching adjustment method, device and plasma generating equipment

Abstract

The present application discloses an impedance matching adjustment method, device and plasma generating equipment, relating to the field of impedance matching technology, wherein the method comprises: determining relevant parameters of a variation law of an equivalent impedance of a plasma chamber; obtaining the equivalent impedance of the first half cycle of a current cycle of the plasma chamber, analyzing the equivalent impedance of the first half cycle of the plasma chamber based on relevant parameters, and predicting the equivalent impedance of the plasma chamber in the second half cycle; and adjusting the equivalent impedance of an impedance matching circuit at the end of the first half cycle of the current cycle so that the sum of the equivalent impedance of the impedance matching circuit and the equivalent impedance predicted for the plasma chamber in the second half cycle matches the equivalent impedance of a radio frequency power supply. The present application aims to solve the technical problem that the speed of impedance matching cannot keep up with the variation of the equivalent impedance of the plasma generating chamber due to the time required from detection to adjustment.

Description

Technical Field

[0001] The present application relates to the field of impedance matching technology, and in particular to an impedance matching adjustment method, device and plasma generating equipment. Background Art

[0002] The RF power supply is a device that generates RF energy and can provide the required RF electric power for the plasma generating equipment.

[0003] The impedance matching network (IMN) is located between the RF power supply and the plasma generator. Its primary function is to ensure that the energy output by the RF power supply is transmitted to the plasma generator to the maximum extent possible. Because the impedances of the RF power supply and the plasma generator may not match, the IMN adjusts its internal circuit parameters (such as inductance and capacitance) to achieve a matching impedance between the two, thereby reducing energy reflection losses and improving energy transmission efficiency.

[0004] In order to match the impedances of the two, the equivalent impedance of the plasma generating device is generally detected first, and then the equivalent impedance of the impedance matching network is adjusted through a motor in combination with the output impedance of the RF power supply, so that the sum of the equivalent impedance of the RF power supply and the equivalent impedance of the matching network and the nonlinear load of the plasma generating device matches. However, since it takes a certain amount of time from detecting the equivalent impedance of the plasma chamber to adjusting the equivalent impedance of the impedance matching network, the speed of impedance matching cannot keep up with the change of the equivalent impedance of the plasma generating device (impedance mismatch). In the case of impedance mismatch, the power output by the RF power supply cannot be effectively transmitted to the plasma generating device, resulting in reduced power transmission efficiency. Summary of the Invention

[0005] The main purpose of the present application is to provide an impedance matching adjustment method, device and plasma generating equipment, aiming to solve the technical problem that the impedance matching speed cannot keep up with the change of the equivalent impedance of the plasma generating chamber because a certain amount of time is required from detection to adjustment.

[0006] To achieve the above objectives, the present application proposes an impedance matching adjustment method, which is applied to a plasma generating device, wherein the plasma generating device includes an impedance matching device and a plasma chamber, wherein the impedance matching device includes an impedance matching circuit and a radio frequency power supply, wherein the input end of the impedance matching circuit is electrically connected to the radio frequency power supply, and the output end of the impedance matching circuit is electrically connected to the plasma chamber, and the method comprises:

[0007] Determining parameters related to a change law of the equivalent impedance of the plasma chamber;

[0008] Obtaining an equivalent impedance of a first half cycle of a current cycle of the plasma chamber, analyzing the equivalent impedance of the first half cycle of the current cycle of the plasma chamber based on the relevant parameters, and predicting the equivalent impedance of the plasma chamber in a second half cycle;

[0009] When the first half of the current cycle is about to end, the equivalent impedance of the impedance matching circuit is adjusted so that the sum of the equivalent impedance of the impedance matching circuit and the equivalent impedance predicted by the plasma chamber in the second half of the cycle matches the equivalent impedance of the RF power supply.

[0010] In one embodiment, the step of determining parameters related to a variation law of the equivalent impedance of the plasma chamber includes:

[0011] Obtaining an equivalent impedance of the plasma chamber during a first half of a plurality of historical cycles, and obtaining an equivalent impedance of the plasma chamber during a second half of a plurality of historical cycles;

[0012] Calculating a first average value of the equivalent impedance of the plasma chamber in a first half period of a plurality of historical periods, and calculating a second average value of the equivalent impedance of the plasma chamber in a second half period of a plurality of historical periods;

[0013] The relevant parameters include a first average value and a second average value.

[0014] In one embodiment, the step of obtaining the equivalent impedance of the first half of the current cycle of the plasma chamber, analyzing the equivalent impedance of the first half of the current cycle of the plasma chamber based on the relevant parameters, and predicting the equivalent impedance of the plasma chamber in the second half of the current cycle includes:

[0015] The first average value is compared with the equivalent impedance of the first half cycle of the current cycle of the plasma chamber. When the difference between the first average value and the equivalent impedance of the first half cycle of the plasma chamber is less than a first preset value, it is predicted that the equivalent impedance of the plasma chamber in the second half cycle is the second average value.

[0016] In one embodiment, the step of determining parameters related to a variation law of the equivalent impedance of the plasma chamber includes:

[0017] determining a first rate of change of the equivalent impedance of the plasma chamber in the first half of the plurality of historical cycles according to the equivalent impedance of the plasma chamber in the first half of the plurality of historical cycles;

[0018] Calculating a plurality of the first change rates to determine an average value of the plurality of the first change rates;

[0019] The relevant parameters include an average value of multiple first change rates.

[0020] In one embodiment, a first predicted range of the change rate of the equivalent impedance of the plasma chamber in the first half cycle is determined based on an average value of a plurality of the first change rates.

[0021] In one embodiment, the step of obtaining the equivalent impedance of the first half of the current cycle of the plasma chamber, analyzing the equivalent impedance of the first half of the plasma chamber based on the relevant parameters, and predicting the equivalent impedance of the plasma chamber in the second half of the cycle includes:

[0022] Determining a rate of change of the equivalent impedance of the first half of the current cycle of the plasma chamber according to the equivalent impedance of the first half of the current cycle of the plasma chamber;

[0023] confirming whether the equivalent impedance of the first half cycle of the plasma chamber is within the first prediction range;

[0024] Before the step of adjusting the equivalent impedance of the impedance matching circuit at the end of the first half cycle of the current cycle so that the sum of the equivalent impedance of the impedance matching circuit and the equivalent impedance predicted for the plasma chamber in the second half cycle matches the equivalent impedance of the RF power supply, the step further includes:

[0025] If the equivalent impedance of the first half of the current cycle of the plasma chamber is within the first prediction range, the change rate of the equivalent impedance of the impedance matching circuit in the first half of the current cycle is adjusted to be within the first prediction range.

[0026] In one embodiment, the relevant parameters include: one or more of a rate of change, a stabilization time, and a fluctuation range of the equivalent impedance of the plasma chamber.

[0027] The present application also proposes an impedance matching device, comprising a processor, a memory, an impedance matching circuit, a radio frequency power supply, and any of the above impedance matching adjustment methods; wherein,

[0028] The processor is configured to process any one of the above impedance matching adjustment methods;

[0029] The memory is used to store any one of the above impedance matching adjustment methods.

[0030] The present application also provides a plasma generating device, comprising a plasma chamber and any one of the impedance matching devices described above.

[0031] The present application can first determine the relevant parameters of the change law of the equivalent impedance of the plasma chamber based on the change of the equivalent impedance of the plasma chamber in multiple historical cycles. The relevant parameters can be one or more of the change rate, stabilization time, and fluctuation range of the equivalent impedance of the plasma chamber; then obtain the equivalent impedance of the first half cycle of the current cycle of the plasma chamber, analyze the equivalent impedance of the first half cycle of the current cycle of the plasma chamber based on the relevant parameters, and determine the equivalent impedance of the plasma chamber in the second half cycle; finally, when the first half cycle of the current cycle is about to end, adjust the equivalent impedance of the impedance matching circuit so that the sum of the equivalent impedance of the impedance matching circuit and the equivalent impedance predicted for the plasma chamber in the second half cycle matches the equivalent impedance of the RF power supply. With such an arrangement, compared with the prior art, the present application adjusts the equivalent resistance of the impedance matching circuit in advance after confirming the equivalent impedance of the plasma chamber in the second half cycle. The advance time can offset the time consumed from detecting the equivalent impedance of the plasma chamber to adjusting the equivalent impedance of the impedance matching circuit, so that the sum of the equivalent impedance of the impedance matching circuit and the equivalent impedance predicted for the plasma chamber in the second half cycle can better match the equivalent impedance of the RF power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0033] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0034] Figure 1 A flow chart illustrating an embodiment of an impedance matching adjustment method of the present application;

[0035] Figure 2 A flowchart illustrating another embodiment of the impedance matching adjustment method of the present application;

[0036] Figure 3 A flowchart illustrating another embodiment of the impedance matching adjustment method of the present application is provided;

[0037] Figure 4 A flowchart illustrating another embodiment of the impedance matching adjustment method of the present application is provided.

[0038] The purpose, features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0040] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0041] In addition, the descriptions of "first", "second", etc. in this application are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0042] The RF power supply is a device that generates RF energy and can provide the required RF electric power for the plasma generating equipment.

[0043] The impedance matching network (IMN) is located between the RF power supply and the plasma generator. Its primary function is to ensure that the energy output by the RF power supply is transmitted to the plasma generator to the maximum extent possible. Because the impedances of the RF power supply and the plasma generator may not match, the IMN adjusts its internal circuit parameters (such as inductance and capacitance) to achieve a matching impedance between the two, thereby reducing energy reflection losses and improving energy transmission efficiency.

[0044] In order to match the impedances of the two, the equivalent impedance of the plasma generating device is generally detected first, and then the equivalent impedance of the impedance matching network is adjusted through a motor in combination with the output impedance of the RF power supply, so that the sum of the equivalent impedance of the RF power supply and the equivalent impedance of the matching network and the nonlinear load of the plasma generating device matches. However, since it takes a certain amount of time from detection to adjustment, the speed of impedance matching cannot keep up with the change of the equivalent impedance of the plasma generating device (impedance mismatch). In the case of impedance mismatch, the power output by the RF power supply cannot be effectively transmitted to the plasma generating device, resulting in reduced power transmission efficiency.

[0045] To this end, the present application provides an impedance matching adjustment method, which aims to solve the technical problem that the impedance matching speed cannot keep up with the change of the equivalent impedance of the plasma generation chamber because a certain amount of time is required from detection to adjustment.

[0046] refer to Figure 1 In one embodiment of the present application, an impedance matching adjustment method is applied to a plasma generating device, wherein the plasma generating device includes an impedance matching device and a plasma chamber, wherein the impedance matching device includes an impedance matching circuit and a radio frequency power supply, wherein an input end of the impedance matching circuit is electrically connected to the radio frequency power supply, and an output end of the impedance matching circuit is electrically connected to the plasma chamber, and the method includes:

[0047] S100: Determine parameters related to a change rule of equivalent impedance of a plasma chamber;

[0048] S200: Obtaining an equivalent impedance of the first half of the current cycle of the plasma chamber, analyzing the equivalent impedance of the first half of the current cycle of the plasma chamber based on relevant parameters, and predicting the equivalent impedance of the plasma chamber in the second half of the current cycle;

[0049] S300: When the first half cycle of the current cycle is ready to end, adjust the equivalent impedance of the impedance matching circuit so that the sum of the equivalent impedance of the impedance matching circuit and the equivalent impedance predicted for the plasma chamber in the second half cycle matches the equivalent impedance of the RF power supply.

[0050] In this embodiment, the impedance matching circuit can adopt one of an L-type impedance matching circuit, a T-type impedance matching circuit or a Π-type impedance matching circuit. The L-type matching circuit is usually composed of an inductor and a capacitor, and these two elements can be connected in series or in parallel; the T-type network impedance matching circuit is composed of two inductors connected in series and two capacitors connected in parallel; the Π-type network impedance matching circuit is composed of two capacitors connected in parallel and two inductors connected in series. By adjusting the values ​​of the inductor and the capacitor, the impedance of the signal source and the impedance of the load can be converted into matching impedances, thereby achieving maximum power transmission and minimum reflection loss.

[0051] The above-mentioned inductor and capacitor are both adjustable, and the processor adjusts the equivalent impedance of the adjustable inductor and the equivalent impedance of the adjustable capacitor through mechanical adjustment driven by a motor according to the detected equivalent impedance of the plasma chamber.

[0052] In this embodiment, one or more of the rate of change, stabilization time, and fluctuation range of the equivalent impedance of the plasma chamber is measured. By measuring and analyzing the rate of change of the equivalent impedance of the plasma chamber in the first half-cycle, the possible change in the equivalent impedance of the chamber in the second half-cycle can be predicted, which helps to adjust the impedance matching circuit in advance to ensure impedance matching between the RF power supply and the plasma chamber. The stabilization time represents the time required for the plasma chamber to reach a stable operating state. Obtaining the stabilization time helps determine when to begin adjusting the impedance matching circuit. For example, if the stabilization time is long, it may be necessary to begin adjusting the impedance matching circuit at the end of the first half-cycle to ensure optimal matching at the beginning of the second half-cycle. Since the equivalent impedance of the plasma chamber may fluctuate within a certain range, obtaining the fluctuation range helps set a tolerance range for impedance matching. Even if the equivalent impedance of the plasma chamber fluctuates, as long as its value remains within the tolerance range, the impedance matching can be considered effective.

[0053] In this embodiment, when the plasma chamber is in the first half of its operation cycle, the plasma chamber is in an initial processing state. When voltage or current is initially applied to the plasma generation region, the plasma may not yet be formed or may be in a low-density state. As the voltage or current continues to be applied, the plasma begins to form and gradually becomes stable. During this process, the resistance of the plasma gradually decreases, causing the equivalent impedance of the plasma chamber to also gradually decrease.

[0054] When the plasma chamber is in the second half of the working cycle, the plasma chamber is in the main processing state. At this time, the plasma is in a relatively stable state, and the equivalent impedance of the equipment remains at the low value at the end of the first half of the cycle and does not change much.

[0055] Specifically, first, the relevant parameters of the change law of the equivalent impedance of the plasma chamber can be determined based on the change of the equivalent impedance of the plasma chamber in multiple historical cycles. The relevant parameters can be one or more of the change rate, stabilization time, and fluctuation range of the equivalent impedance of the plasma chamber; then, the equivalent impedance of the first half cycle of the plasma chamber is obtained, and the equivalent impedance of the first half cycle of the current cycle of the plasma chamber is analyzed based on the relevant parameters to determine the equivalent impedance of the plasma chamber in the second half cycle; finally, when the first half cycle of the current cycle is about to end, the equivalent impedance of the impedance matching circuit is adjusted so that the sum of the equivalent impedance of the impedance matching circuit and the equivalent impedance predicted for the plasma chamber in the second half cycle matches the equivalent impedance of the RF power supply. With such an arrangement, compared with the prior art, the present application adjusts the equivalent resistance of the impedance matching circuit in advance after confirming the equivalent impedance of the plasma chamber in the second half cycle. The advance time and the time consumed from detecting the equivalent impedance of the plasma chamber to adjusting the equivalent impedance of the impedance matching circuit offset each other, so that the sum of the equivalent impedance of the impedance matching circuit and the equivalent impedance predicted for the plasma chamber in the second half cycle can better match the equivalent impedance of the RF power supply.

[0056] refer to Figure 2 In one embodiment of the present application, the step of determining parameters related to the variation law of the equivalent impedance of the plasma chamber includes:

[0057] S101: Obtaining an equivalent impedance of a plasma chamber in a first half of a plurality of historical cycles, and obtaining an equivalent impedance of a plasma chamber in a second half of a plurality of historical cycles;

[0058] S102: calculating a first average value of equivalent impedances of the plasma chamber in the first half of a plurality of historical cycles, and calculating a second average value of equivalent impedances of the plasma chamber in the second half of a plurality of historical cycles;

[0059] The relevant parameters include a first average value and a second average value.

[0060] In this embodiment, equivalent impedance samples of the first half cycle and the second half cycle of multiple historical cycles of the plasma chamber are obtained respectively, so as to establish a corresponding mathematical model and calculate a first average value of the equivalent impedance of the plasma chamber in the first half cycle of multiple historical cycles and a second average value of the equivalent impedance in the second half cycle. The first average value and the second average value respectively reflect the stability or normal impedance state of the plasma chamber in the first half cycle and the second half cycle.

[0061] In this embodiment, the steps of obtaining the equivalent impedance of the first half of the current cycle of the plasma chamber, analyzing the equivalent impedance of the first half of the cycle of the plasma chamber based on relevant parameters, and predicting the equivalent impedance of the plasma chamber in the second half of the cycle include:

[0062] S201: comparing the first average value with the equivalent impedance of the first half of the current cycle of the plasma chamber, and when the difference between the first average value and the equivalent impedance of the first half of the current cycle of the plasma chamber is less than a first preset value, predicting that the equivalent impedance of the plasma chamber in the second half of the current cycle is a second average value;

[0063] The comparison is to determine whether the equivalent impedance of the first half of the current cycle is similar to the average value of the first half of the past cycles. If the difference is less than a preset threshold (first preset value), then it can be considered that the current cycle is similar to the past cycles in the first half of the cycle.

[0064] In this case, based on this similarity, it can be assumed that the equivalent impedance of the current cycle in the second half will also be similar to the average value of the past multiple cycles (i.e., the second average value). Therefore, the second average value can be used as the predicted value or approximate value of the equivalent impedance of the second half of the current cycle, that is, the equivalent resistance of the impedance matching network is adjusted in advance so that the sum of the equivalent impedance of the impedance matching circuit and the plasma chamber in the second half of the cycle (the second average value) matches the equivalent impedance of the RF power supply, offsetting the adjustment of the equivalent impedance of the impedance matching circuit from the equivalent impedance of the plasma chamber to the equivalent impedance of the impedance matching network, so that the sum of the equivalent impedance of the impedance matching circuit and the equivalent impedance predicted for the plasma chamber in the second half of the cycle matches the equivalent impedance of the RF power supply.

[0065] refer to Figure 3 In one embodiment of the present application, the step of determining parameters related to the variation law of the equivalent impedance of the plasma chamber includes:

[0066] S103: determining a first change rate of the equivalent impedance of the plasma chamber in the first half of the plurality of historical cycles according to the equivalent impedance of the plasma chamber in the first half of the plurality of historical cycles;

[0067] S104: Calculate the multiple first change rates to determine an average value of the multiple first change rates.

[0068] A second rate of change of the equivalent impedance of the plasma chamber at the end of the second half of the plurality of historical cycles may also be determined based on the equivalent impedance of the plasma chamber at the end of the second half of the plurality of historical cycles;

[0069] The plurality of second change rates are calculated to determine an average value of the plurality of second change rates.

[0070] The relevant parameters include an average value of a plurality of first change rates and an average value of a plurality of second change rates.

[0071] In this embodiment, the average of the multiple first change rates and the average of the multiple second change rates both reflect the regular variations in the rate of change of the equivalent impedance of the plasma chamber over multiple historical cycles, and can serve as the changing trend of the equivalent impedance of the plasma chamber in future cycles. The average values ​​can also serve as important input parameters for constructing a predictive model. Through machine learning or statistical learning methods, a predictive model can be established between the change in the equivalent impedance of the plasma chamber and process parameters, which can be used to predict the performance of the plasma chamber in future cycles and make adjustments in advance.

[0072] In this embodiment, the step of determining parameters related to the variation law of the equivalent impedance of the plasma chamber further includes:

[0073] S105: determining a first predicted range of a change rate of the equivalent impedance of the plasma chamber in the first half cycle according to an average value of the plurality of first change rates;

[0074] A second prediction range of the change rate of the equivalent impedance of the plasma chamber in the second half cycle is determined according to an average value of the plurality of second change rates.

[0075] In this embodiment, the first prediction range is based on the average of multiple first change rates as the median value, and the upper and lower limits of the prediction range are determined based on the standard deviation, variance, or specific confidence level of the change rate of the equivalent impedance of the plasma chamber in the first half of multiple historical cycles. For example, assuming the average of the multiple first change rates is μ1 and the standard deviation is σ1, where the standard deviation measures the dispersion of the data set, that is, the distribution of data points relative to the average. Selecting an appropriate confidence level, such as 95%, means that the first prediction range can cover approximately 95% of the historical data points. Based on the average, standard deviation, and confidence level, the upper and lower limits of the prediction range can be calculated. For normally distributed data, a 95% confidence level typically corresponds to approximately twice the standard deviation. Therefore, the upper and lower limits of the first prediction range can be set as μ1±2σ1. Similarly, for the second prediction range, the upper and lower limits of the prediction range can also be calculated based on the average μ2 and standard deviation σ2 of the multiple second change rates using the same method. Detailed description is omitted here.

[0076] refer to Figure 4 In this embodiment, the steps of obtaining the equivalent impedance of the first half of the current cycle of the plasma chamber, analyzing the equivalent impedance of the first half of the current cycle of the plasma chamber based on relevant parameters, and predicting the equivalent impedance of the plasma chamber in the second half of the current cycle include:

[0077] S202: determining a rate of change of the equivalent impedance of the first half of the current cycle of the plasma chamber according to the equivalent impedance of the first half of the current cycle of the plasma chamber;

[0078] S203: confirming whether the equivalent impedance of the first half cycle of the plasma chamber is within a first prediction range;

[0079] Before the step of adjusting the equivalent impedance of the impedance matching circuit at the end of the first half cycle of the current cycle so that the sum of the equivalent impedance of the impedance matching circuit and the equivalent impedance predicted for the plasma chamber in the second half cycle matches the equivalent impedance of the RF power supply, the method further includes:

[0080] S301: If the equivalent impedance of the first half of the current cycle of the plasma chamber is within a first prediction range, adjust the change rate of the equivalent impedance of the impedance matching circuit in the first half of the current cycle to be within the first prediction range.

[0081] In this embodiment, if the rate of change of the equivalent impedance of the plasma chamber in the first half of the current cycle is within the first prediction range, it can be considered that the current cycle is similar to the first half of the previous cycles. Therefore, the rate of change of the equivalent impedance of the impedance matching circuit in the first half of the cycle can be adjusted to be within the first prediction range, so that the rate of change of the equivalent impedance of the impedance matching circuit will be the same as the rate of change of the equivalent impedance of the plasma chamber, so that the impedance matching circuit can achieve a better impedance matching effect in the first half of the cycle, and when the first half of the current cycle is ready to end, the equivalent impedance of the impedance matching circuit and the equivalent impedance of the plasma chamber predicted in the second half of the cycle are adjusted. The sum of the (second average value) matches the equivalent impedance of the RF power supply. Since the rate of change of the equivalent impedance of the impedance matching circuit is within the first predicted range during the first half cycle, at the end of the first half cycle, the sum of the equivalent impedance of the impedance matching circuit and the equivalent impedance of the plasma chamber is not much different from the equivalent impedance of the RF power supply. With this arrangement, not only can the time for adjusting the equivalent resistance of the impedance matching circuit in advance be offset by the time consumed from detection to adjustment, but the time for adjusting the sum of the equivalent impedance of the impedance matching circuit and the equivalent impedance of the plasma chamber in the second half cycle to match the equivalent impedance of the RF power supply is also shortened, thereby further improving the efficiency of impedance matching.

[0082] If the rate of change of the equivalent impedance of the plasma chamber is not within the first prediction range in the early part of the first half of the current cycle, it may be that the plasma chamber is in the startup stage, preparation stage and ventilation stage of the initial processing state for a long time. During this stage, the equipment has just started to power on, start the system and perform necessary self-test and initialization operations. Therefore, the equivalent impedance of the plasma chamber at this stage will not be within the first prediction range.

[0083] If the rate of change of the plasma chamber's equivalent impedance is not within the first predicted range for multiple first half-cycles, it may indicate that the performance of the plasma chamber is changing, possibly due to equipment aging, wear, contamination, or other unknown factors. This can serve as an early warning signal, prompting operators or maintenance personnel to perform inspections and maintenance to avoid potential failures.

[0084] In this embodiment, since the equivalent impedance of the plasma chamber gradually changes to the equivalent impedance of the initial stage of the first half cycle when the operation ends, that is, at the end of the second half cycle, it is necessary to determine whether the rate of change of the equivalent impedance of the plasma chamber in the second half cycle is within the second prediction range. If so, it is confirmed that the plasma generating device is in the stage of preparing to end the operation, and the equivalent impedance of the impedance matching circuit is adjusted so that the sum of the equivalent impedance of the plasma chamber in the initial stage of the first half cycle and the equivalent impedance of the impedance matching circuit is consistent with the equivalent impedance of the RF power supply, thereby preparing for the operation of the next cycle.

[0085] The present application also proposes an impedance matching device, comprising a processor, a memory, an impedance matching circuit, a radio frequency power supply, and any one of the above impedance matching adjustment methods;

[0086] The processor is used to process the impedance matching adjustment method;

[0087] The memory is used to store the above impedance matching adjustment method.

[0088] It is worth noting that since the impedance matching device of the present application is based on the above-mentioned impedance matching adjustment method, the embodiments of the impedance matching device of the present application include all technical solutions of all embodiments of the above-mentioned impedance matching adjustment method, and the technical effects achieved are also exactly the same, which will not be repeated here.

[0089] The present application also provides a plasma generating device, comprising a plasma chamber and the above-mentioned impedance matching device.

[0090] It is worth noting that since the plasma generating device of the present application is based on the above-mentioned impedance matching device, the embodiments of the plasma generating device of the present application include all technical solutions of all embodiments of the above-mentioned impedance matching device, and the technical effects achieved are also exactly the same, which will not be repeated here.

[0091] The above description is only part of the embodiments of the present application and does not limit the patent scope of the present application. All equivalent structural changes made by using the contents of the present application specification and drawings under the technical concept of the present application, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present application.

Claims

1. An impedance matching adjustment method, applied to a plasma generating device, characterized in that: The plasma generating device includes an impedance matching device and a plasma chamber, the impedance matching device includes an impedance matching circuit and a radio frequency power supply, the input end of the impedance matching circuit is electrically connected to the radio frequency power supply, and the output end of the impedance matching circuit is electrically connected to the plasma chamber, and the method includes: Determining parameters related to a change law of the equivalent impedance of the plasma chamber; Obtaining an equivalent impedance of a first half cycle of a current cycle of the plasma chamber, analyzing the equivalent impedance of the first half cycle of the current cycle of the plasma chamber based on the relevant parameters, and predicting the equivalent impedance of the plasma chamber in a second half cycle; When the first half of the current cycle is about to end, the equivalent impedance of the impedance matching circuit is adjusted so that the sum of the equivalent impedance of the impedance matching circuit and the equivalent impedance predicted by the plasma chamber in the second half of the cycle matches the equivalent impedance of the RF power supply.

2. The method according to claim 1, wherein The step of determining relevant parameters of the variation law of the equivalent impedance of the plasma chamber comprises: Obtaining an equivalent impedance of the plasma chamber during a first half of a plurality of historical cycles, and obtaining an equivalent impedance of the plasma chamber during a second half of a plurality of historical cycles; Calculating a first average value of the equivalent impedance of the plasma chamber in a first half period of a plurality of historical periods, and calculating a second average value of the equivalent impedance of the plasma chamber in a second half period of a plurality of historical periods; The relevant parameters include a first average value and a second average value.

3. The method according to claim 2, wherein The steps of obtaining the equivalent impedance of the first half of the current cycle of the plasma chamber, analyzing the equivalent impedance of the first half of the current cycle of the plasma chamber based on the relevant parameters, and predicting the equivalent impedance of the plasma chamber in the second half of the current cycle include: The first average value is compared with the equivalent impedance of the first half cycle of the current cycle of the plasma chamber. When the difference between the first average value and the equivalent impedance of the first half cycle of the plasma chamber is less than a first preset value, it is predicted that the equivalent impedance of the plasma chamber in the second half cycle is the second average value.

4. The method according to claim 2, wherein The step of determining relevant parameters of the variation law of the equivalent impedance of the plasma chamber comprises: determining a first rate of change of the equivalent impedance of the plasma chamber in the first half of the plurality of historical cycles according to the equivalent impedance of the plasma chamber in the first half of the plurality of historical cycles; Calculating a plurality of the first change rates to determine an average value of the plurality of the first change rates; The relevant parameters include an average value of multiple first change rates.

5. The method according to claim 4, wherein The step of determining parameters related to the variation law of the equivalent impedance of the plasma chamber further includes: A first predicted range of the change rate of the equivalent impedance of the plasma chamber in the first half cycle is determined according to an average value of the plurality of first change rates.

6. The method according to claim 5, wherein The step of obtaining the equivalent impedance of the first half of the current cycle of the plasma chamber, analyzing the equivalent impedance of the first half of the current cycle of the plasma chamber based on the relevant parameters, and predicting the equivalent impedance of the plasma chamber in the second half of the current cycle includes: Determining a rate of change of the equivalent impedance of the first half of the current cycle of the plasma chamber according to the equivalent impedance of the first half of the current cycle of the plasma chamber; confirming whether the equivalent impedance of the first half cycle of the plasma chamber is within the first prediction range; Before the step of adjusting the equivalent impedance of the impedance matching circuit at the end of the first half cycle of the current cycle so that the sum of the equivalent impedance of the impedance matching circuit and the equivalent impedance predicted for the plasma chamber in the second half cycle matches the equivalent impedance of the RF power supply, the step further includes: If the equivalent impedance of the first half of the current cycle of the plasma chamber is within the first prediction range, the change rate of the equivalent impedance of the impedance matching circuit in the first half of the current cycle is adjusted to be within the first prediction range.

7. The method according to claim 1, wherein The relevant parameters include: one or more of a rate of change, a stabilization time, and a fluctuation range of the equivalent impedance of the plasma chamber.

8. An impedance matching device, characterized in that: The device comprises a processor, a memory, an impedance matching circuit, a radio frequency power supply, and an impedance matching adjustment method according to any one of claims 1 to 7; wherein, The processor is configured to process the impedance matching adjustment method according to any one of claims 1 to 7; The memory is used to store the impedance matching adjustment method according to any one of claims 1 to 7.

9. A plasma generating device, characterized in that: The device comprises a plasma chamber and the impedance matching device according to claim 8.

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