Method, apparatus, and high-frequency power supply system for suppressing arcs in a plasma cavity

Abstract

The present application relates to a method, apparatus and high frequency power supply system for suppressing an arc in a plasma cavity. The method includes the steps of: obtaining a reflection coefficient in the plasma cavity by arc detection sampling, the reflection coefficient including an instantaneous reflection coefficient and an average reflection coefficient; comparing an absolute value of a difference between the instantaneous reflection coefficient and the average reflection coefficient with a predetermined reflection coefficient threshold; when it is determined that an arc occurs in the plasma cavity according to the comparison result, instructing a state machine to lock the last operating parameter corresponding to a restoration node of the high frequency power supply system, suspend the arc detection sampling, and cut off the power output of the output end coupled to the plasma cavity by a control module of a PID controller; and instructing the control module of the PID controller to restore the power output of the output end according to the operating parameters and restore the arc detection sampling after the arc in the plasma cavity is removed. Thus, a highly accurate arc suppression process in the cavity is realized.

Description

[Technical Field]

[0001] This application relates to the technical field of high-frequency system detection and control, and more particularly to a method, apparatus, and high-frequency power supply system for suppressing arcs in a plasma cavity. [Background technology]

[0002] As high-frequency power supply technology has developed, its application fields have expanded from the traditional vacuum field to semiconductors and even other fields such as cosmetics. A so-called high-frequency power supply system typically includes a high-frequency power supply and a plasma cavity. The high-frequency power supply is an attached power supply to the plasma cavity and is often used in equipment for high-frequency sputtering, PECVD chemical vapor deposition, and reactive ion etching. In actual applications, if an arc is generated within the plasma cavity, it reduces product yield and also leads to electromagnetic interference (EMI) problems. Regarding arc generation within a plasma cavity, conventional suppression techniques primarily rely on detecting the instantaneous rate of change of voltage and current, while arc extinguishing techniques suppress the arc by using hardware equipment and designing an arc suppressor. However, during the development process, the inventors discovered that at least the conventional techniques suffer from a technical challenge: the accuracy of arc suppression is not high. [Overview of the Initiative] [Problems that the invention aims to solve]

[0003] Based on the above, it is necessary to provide a method for suppressing arcs in a plasma cavity, an arc suppression device for a plasma cavity, a high-frequency power supply system, and a computer-readable storage medium that can significantly improve the accuracy of arc suppression within the cavity to address the aforementioned technical challenges.

[0004] To achieve the above objective, this application provides the following technical solutions. [Means for solving the problem]

[0005] In one aspect, the present invention provides a method for suppressing arcs in a plasma cavity, comprising the steps of: obtaining a reflection coefficient in the plasma cavity by arc detection sampling, wherein the reflection coefficient includes an instantaneous reflection coefficient and an average reflection coefficient; comparing the absolute value of the difference between the instantaneous reflection coefficient and the average reflection coefficient with a predetermined reflection coefficient threshold; if it is determined from the comparison result that an arc has occurred in the plasma cavity, instructing the state machine to lock the last operating parameter corresponding to the restore node of the high-frequency power supply system, suspend arc detection sampling, and shut off the power output of the output terminal coupled to the plasma cavity by the control module of the PID controller; and, after the arc in the plasma cavity has been removed, instructing the control module of the PID controller to restore the power output of the output terminal and restore arc detection sampling based on the operating parameter.

[0006] In one embodiment, the process for determining whether or not an arc has occurred in the plasma cavity based on the comparison results includes the step of determining whether or not an arc has occurred in the plasma cavity based on the fact that the absolute value of the difference is less than a predetermined reflection coefficient threshold and that predetermined analytical judgment conditions are met.

[0007] In one embodiment, the predetermined analysis judgment condition includes determining that no arc is occurring in the plasma cavity if the absolute value of the difference is less than a predetermined reflection coefficient threshold for N consecutive times, where N is a positive integer of 2 or more.

[0008] In one embodiment, the predetermined analysis and judgment conditions include determining that no arc is occurring in the plasma cavity if the absolute value of the difference exceeds a predetermined reflection coefficient threshold M times discontinuously within a predetermined period, where M is a positive integer of 1 or more.

[0009] In one embodiment, the predetermined analysis and judgment conditions include determining that an arc has occurred in the plasma cavity if the absolute value of the difference exceeds a predetermined reflection coefficient threshold once.

[0010] In one embodiment, the predetermined analysis and judgment condition includes that when the absolute value of the difference continuously exceeds a predetermined reflection coefficient threshold for N times, it is determined that an arc has occurred in the plasma cavity, and N is a positive integer greater than or equal to 2.

[0011] In one embodiment, the detection period of arc detection sampling includes a plurality of detection periods arranged in ascending order. The predetermined reflection coefficient threshold is a coefficient threshold set manually or a coefficient threshold adaptively set by the system. The method includes: from the shortest detection period, when the frequency of arc occurrence in the plasma cavity is lower than a predetermined frequency threshold, extending the detection period to the next longer detection period; otherwise, without changing the detection period, adaptively increasing the coefficient threshold set by the system by a multiple or a constant value.

[0012] In one embodiment, when it is determined that no arc has occurred in the plasma cavity based on the comparison result, the method further includes maintaining the operation of the PID controller in the normal control state. The normal control state includes maintaining the current operation state of the control module, continuing arc detection sampling to obtain the reflection coefficient in the plasma cavity, recording the average reflection coefficient in the current normal operation state, recording the operation parameters for the control module, recording the operation variable parameters of the unit device at the output end, and setting the current normally operating time node as the restoration node and continuously updating it.

[0013] In one embodiment, the process of instructing the state machine to lock the last operation parameter corresponding to the restoration node of the high-frequency power supply system includes instructing the state machine to lock the last average reflection coefficient in the normal operation state, instructing the control module to lock the operation parameters, and instructing to lock the operation variable parameters of each unit device at the output end.

[0014] In one embodiment, the step of obtaining the reflectance coefficient in the plasma cavity by arc detection sampling includes the step of obtaining the instantaneous reflectance coefficient by employing periodic, fixed-point sampling, and the step of calculating the average reflectance coefficient from all the instantaneous reflectance coefficients currently sampled, where each sampling, average value calculation, and threshold comparison are all synchronous multithreaded processes at single time intervals.

[0015] In another aspect, the present invention provides an arc suppression device in a plasma cavity, comprising: a detection sampling module for obtaining the reflectance coefficient in a plasma cavity by arc detection sampling, the detection sampling module including an instantaneous reflectance coefficient and an average reflectance coefficient; a coefficient comparison module for comparing the absolute value of the difference between the instantaneous reflectance coefficient and the average reflectance coefficient with a predetermined reflectance coefficient threshold; an arc extinguishing module for instructing a state machine to lock the last operating parameter corresponding to the restore node of the high-frequency power supply system, pause arc detection sampling, and shut off the power output of the output terminal coupled to the plasma cavity by the control module of a PID controller, if it is determined based on the comparison result that an arc has occurred in the plasma cavity; and an output recovery module for instructing the control module of the PID controller to restore the power output of the output terminal and restore arc detection sampling based on the operating parameter after the arc in the plasma cavity has been removed.

[0016] In another aspect, the present invention provides a high-frequency power supply system comprising a high-frequency power supply, a PID controller, and a plasma cavity, wherein the high-frequency power supply is electrically connected to the plasma cavity via the PID controller, and the PID controller is used to implement an arc suppression process step comprising: obtaining a reflection coefficient in the plasma cavity by arc detection sampling, wherein the reflection coefficient includes an instantaneous reflection coefficient and an average reflection coefficient; comparing the absolute value of the difference between the instantaneous reflection coefficient and the average reflection coefficient with a predetermined reflection coefficient threshold; if it is determined based on the comparison result that an arc has occurred in the plasma cavity, locking the last operating parameter corresponding to the restore node of the high-frequency power supply system, pausing arc detection sampling, and shutting off the power output of the output terminal coupled to the plasma cavity; and, after the arc in the plasma cavity has been removed, restoring the power output of the output terminal based on the operating parameter and restoring arc detection sampling.

[0017] In yet another aspect, the present invention provides a computer-readable storage medium that stores a computer program which, when executed by a processor, implements the steps of any one of the above-described methods for suppressing arcs in a plasma cavity.

[0018] One of the above technical solutions has the following advantages and beneficial effects.

[0019] According to the above-described method, apparatus, and high-frequency power supply system for suppressing arcs in a plasma cavity, instantaneous and average reflection coefficients in the plasma cavity are obtained by arc detection sampling and compared with a predetermined reflection coefficient threshold to accurately determine whether or not an arc has occurred in the plasma cavity. If it is determined that an arc has occurred in the plasma cavity, the last operating parameter corresponding to the recovery node of the high-frequency power supply system is locked, arc detection sampling is temporarily suspended, and the state machine instructs the control module of the PID controller to shut off the power output of the output terminal coupled to the plasma cavity, thereby temporarily suspending the power output of the high-frequency power supply to the plasma cavity. After the arc in the plasma cavity is removed, the power output of the output terminal is restored based on the operating parameters, and the control module of the PID controller is instructed to restore arc detection sampling, thereby restoring the power output of the high-frequency power supply to the plasma cavity. This achieves highly accurate suppression of arcs in the plasma cavity.

[0020] The above solution significantly improves the accuracy of determining whether or not an arc has occurred compared to conventional methods by using a comparison mechanism between the average reflection coefficient (also called the average gamma value) and the critical value. If it is determined that an arc has occurred, the state machine instructs the system to lock the last operating parameter corresponding to the system's recovery node, temporarily suspend arc detection, and temporarily suspend power output. This allows for accurate and rapid recovery of power output based on the locked operating parameter after the arc has been removed from the cavity, achieving highly accurate arc suppression within the cavity, reducing the cost of arc suppression, improving efficiency, and increasing adaptability.

[0021] To more clearly explain the embodiments of this application or the technical solutions in the prior art, the drawings necessary for describing the embodiments or the prior art will be briefly described below. Naturally, the drawings described below are only a part of the embodiments of this application, and those skilled in the art will be able to conceive of other drawings based on these drawings without requiring any creative effort. [Brief explanation of the drawing]

[0022] [Figure 1] This is a schematic environmental flowchart of a method for suppressing arcs in a plasma cavity in one embodiment. [Figure 2] This is a schematic diagram illustrating the sampling of instantaneous values ​​in one embodiment. [Figure 3] This is a schematic diagram of the ARC suppression stage in one embodiment. [Figure 4] This is a flowchart of ARC monitoring and suppression processing in one embodiment. [Figure 5] This is a block diagram of the modular structure of an arc suppression device in a plasma cavity in one embodiment. [Figure 6] This is a schematic diagram of the structural frame of a high-frequency power supply system in one embodiment. [Figure 7] This is a schematic diagram of the configuration of an ARC processing module in one embodiment. [Modes for carrying out the invention]

[0023] To make the purpose, technical solutions, and advantages of this application clearer and easier to understand, the application will be described in more detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are for interpretation purposes only and are not intended to limit this application.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art relating to this application. Terms used herein in the specification are solely for the purpose of describing the specific embodiments and are not intended to limit this application.

[0025] It should be noted that the “Examples” as used herein mean that, by their specific features, structures, or properties, they may be included in at least one embodiment of the present invention. The term, as it appears in the specification, does not necessarily refer to the same embodiment, nor does it mean that an embodiment is exclusively independent or alternative to another embodiment.

[0026] Those skilled in the art will understand that the embodiments described herein may be combined with other embodiments. The terms “and / or” as used in this disclosure and the appended claims mean any and all possible combinations of one or more relatedly listed items, and include such combinations.

[0027] In practical application research, the inventor discovered that determining whether or not an arc phenomenon has occurred solely by detecting the rate of change of current and voltage can lead to misjudgments and affect the normal operation of the system. While arc phenomena can be effectively suppressed by employing a specialized arc extinguishing device, this increases the complexity and manufacturing cost of the system, and the need for an arc extinguishing device is not high in usage scenarios where only small arcs occur. Furthermore, while arc extinguishing devices need to be designed for specific scenarios, the variety of arc types within a plasma cavity makes it difficult for a single arc extinguishing device to be effective. Therefore, this application proposes a novel method for suppressing arcs within a plasma cavity, addressing the technical challenge of low arc suppression accuracy that exists in at least the prior art, thereby achieving high-precision arc suppression within the cavity.

[0028] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings in the embodiment diagrams of the present invention.

[0029] In one embodiment, as shown in Figure 1, a method for suppressing arcs in a plasma cavity that can be applied to various high-frequency power supply systems is provided. The method includes the following steps S12 to S18.

[0030] In S12, the reflectance coefficient in the plasma cavity is obtained by arc detection sampling, and the reflectance coefficient includes the instantaneous reflectance coefficient and the average reflectance coefficient.

[0031] Arc detection sampling is understood to be a detection method that easily calculates the reflection coefficient (which may be called the gamma value in this specification) within a plasma cavity by sampling measurement information of the plasma cavity using an existing sensor system or an external sensor device in the system. The measurement information to be sampled may be at least one or a combination of voltage value, current value, power value, cavity impedance value, and power supply impedance value, as long as the reflection coefficient within the plasma cavity can be accurately measured. The instantaneous reflection coefficient is the current reflection coefficient within the plasma cavity sampled at the present time, and the average reflection coefficient is the average coefficient value calculated from all reflection coefficients sampled up to the present time.

[0032] Specifically, during the operation of the high-frequency power supply system, arc detection sampling is performed on the system (mainly the relevant electrical parameters of the plasma cavity) to obtain the instantaneous reflectance coefficient within the plasma cavity and calculate the corresponding average reflectance coefficient.

[0033] In S14, the absolute value of the difference between the instantaneous reflection coefficient and the average reflection coefficient is compared with a predetermined reflection coefficient threshold.

[0034] For the sake of explanation, the instantaneous reflection coefficient is Γ cur It is written that the average reflection coefficient is Γ aver It can be written as follows, and the above comparison process is |Γ cur -Γ aver |<Γ th It is understood that it can be described as determining whether or not the condition is true, and if it is true, indicating that the system is currently operating normally and no arc is occurring in the cavity, and if it is not true, indicating that the system is currently operating abnormally and an arc has occurred in the cavity.

[0035] The process described above, which involves arc detection sampling, gamma mean calculation, and comparison processing, to accurately determine whether or not an arc has occurred within the cavity may be called ARC (arc) monitoring.

[0036] In S16, if it is determined based on the comparison results that an arc has occurred in the plasma cavity, the state machine instructs the control module of the PID controller to lock the last operating parameter corresponding to the restoration node of the high-frequency power supply system, pause arc detection sampling, and shut off the power output of the output terminal coupled to the plasma cavity.

[0037] In a system, the state machine is understood to be a state control unit that instructs each module of the system to lock and / or unlock operating parameters. During system operation, a PID controller may have a normal control state and a shut-off control state. The PID controller samples to obtain instantaneous gamma values ​​and calculates the average value, and |Γ cur -Γ aver |<Γ th The system compares the instantaneous gamma value with the gamma value and obtains the comparison result. If it determines that no arc has occurred, the system is in a normal control state. In this state, the PID controller maintains the current operation of the control module and continues to detect the gamma value. At the same time, it records each operating parameter at the current time node, which may also be a restore node. The data at this restore node is continuously updated under normal control conditions.

[0038] If it is determined that an arc has occurred in the plasma cavity, the PID controller switches to a shut-off control state. In this state, the state machine also switches to an operating state, instructing each module to lock the last operating parameter corresponding to the recovery node and to temporarily suspend arc detection sampling for a certain period X (the length of this period X can be set based on the plasma cavity's potential drop time + zero potential time + potential rise time) (ARC monitoring). On the other hand, the control module of the PID controller remains in an operating state and shuts off the power output of the output terminal coupled to the plasma cavity, thereby shutting off the high-frequency power output of the high-frequency power supply to the plasma cavity. After the power output is shut off, the plasma cavity experiences a potential drop, a period of quiescence (zero potential time), and a subsequent potential rise time (potential rise time) after power recovery.

[0039] In S18, after the arc in the plasma cavity has been removed, the control module of the PID controller is instructed to restore power output at the output terminal and restore arc detection sampling based on the operating parameters.

[0040] It is understood that after the control module of the PID controller shuts off the power output of the output terminal coupled to the plasma cavity, the potential of the plasma cavity drops and is maintained at zero potential for a predetermined time to extinguish the arc generated in the cavity. After a predetermined period of stillness (the length of this time can be set according to the statistical rules of the shortest time to extinguish the arc / arc extinguishing time in actual applications), the arc is extinguished, and at this time the state machine switches the operating state to restore each module to a normal operating state based on the operating parameters of the last restore node locked before arc extinguishing, instructing the control module of the PID controller to restore the power output coupled to the plasma cavity, and instructing the PID controller to restore ARC monitoring, thereby proceeding to the next round of arc monitoring and suppression operation. As those skilled in the art will understand, if it is detected that an arc is still occurring in the cavity after operation has been restored, the above operation can be repeated to suppress the arc, and the zero-potential time can be selectively extended to achieve a better arc extinguishing effect.

[0041] In the above method for suppressing arcs within a plasma cavity, instantaneous and average reflection coefficients within the plasma cavity are obtained by arc detection sampling, and then compared with a predetermined reflection coefficient threshold to accurately determine whether or not an arc has occurred within the plasma cavity. If it is determined that an arc has occurred within the plasma cavity, the last operating parameter corresponding to the recovery node of the high-frequency power supply system is locked, arc detection sampling is temporarily suspended, and the power output of the output terminal coupled to the plasma cavity is shut off by the control module of the PID controller, i.e., the power output of the high-frequency power supply to the plasma cavity is temporarily suspended by the state machine. After the arc in the plasma cavity is removed, the control module of the PID controller is instructed to restore the power output of the output terminal and restore arc detection sampling, i.e., restore the power output of the high-frequency power supply to the plasma cavity, based on the operating parameters. This achieves highly accurate suppression of arcs within the plasma cavity.

[0042] Compared to conventional methods, the above solution significantly improves the accuracy of determining whether or not an arc has occurred by using a comparison mechanism between the average reflection coefficient (which may also be called the average gamma value) and the critical value. If it is determined that an arc has occurred, the state machine instructs the system to lock the last operating parameter corresponding to the system's recovery node, temporarily suspend arc detection, and temporarily suspend power output. As a result, after the arc has been removed from the cavity, power output can be accurately and quickly restored based on the locked operating parameter, enabling highly accurate arc suppression processing within the cavity, reducing arc suppression costs, improving efficiency, and increasing adaptability.

[0043] In one embodiment, the method for determining whether or not an arc in a plasma cavity has been removed may be to detect the energy in the cavity and determine whether or not the remaining energy in the cavity is zero or lower than a predetermined energy threshold (if the remaining energy in the cavity is zero or lower than a predetermined energy threshold, it can be determined that the arc has been removed; otherwise, it can be determined that it has not been removed); or to determine whether or not the arc in the cavity has been removed after a predetermined time has elapsed since the power output was cut off; or to determine whether or not the arc in the cavity has been removed by visual inspection (if it is observed that there is no arc in the cavity, it can be determined that the arc has been removed; otherwise, it can be determined that it has not been removed), but the method is not limited to these. Other methods of determination are acceptable as long as they can accurately determine whether or not the arc has been removed from the cavity. By determining the arc state in the cavity using the above method, the state machine can be instructed immediately and accurately to switch to an operating state, and each module can be instructed to return to its pre-lock operating state. This reduces power cut-off time and improves the overall efficiency of arc suppression processing.

[0044] In one embodiment, step S12 may specifically include the steps of obtaining instantaneous reflection coefficients by employing periodic, fixed-point sampling, and calculating the average reflection coefficient using all currently sampled instantaneous reflection coefficients, where each sampling, average calculation, and threshold comparison are all synchronous multithreaded processes at single time intervals.

[0045] Specifically, regular and fixed-point sampling is adopted for detecting the instantaneous reflection coefficient sampling, and all sampling values are valid values and are all used for calculating the gamma average value. Further, for each sampling, coefficient and average value calculation, and threshold comparison process, in this embodiment, as shown in FIG. 2, the PID controller adopts synchronous multi-thread processing for a single time interval and can achieve the same purpose at multiple synchronous locations, thereby further improving the reliability of reflection detection and arc judgment in the cavity.

[0046] In one embodiment, for the process of determining whether an arc has occurred in the plasma cavity based on the comparison result in step S16 above, it may include determining whether an arc has occurred in the plasma cavity based on the fact that the absolute value of the difference is less than a predetermined reflection coefficient threshold and satisfies a predetermined analysis and judgment condition.

[0047] In the above embodiment, |Γ cur -Γ aver |<Γ th It can be understood that by determining whether it holds, it is possible to directly determine whether an arc has occurred in the cavity. In this embodiment, in order to further improve the judgment accuracy regarding arc occurrence, |Γ cur -Γ aver |<Γ th By determining whether it holds and whether a predetermined analysis and judgment condition is satisfied, it is possible to more accurately determine whether an arc has occurred in the cavity.

[0048] In one embodiment, optionally, the predetermined analysis and judgment condition may include that when the absolute value of the difference is less than the predetermined reflection coefficient threshold for N consecutive times, it is determined that no arc has occurred in the plasma cavity, and N is a positive integer greater than or equal to 2.

[0049] Specifically, when it is determined that |Γ cur -Γ aver |<Γ th for N consecutive times, it can be determined that no arc has occurred in the current plasma cavity.

[0050] In one embodiment, the predetermined analytical judgment condition may selectively include determining that no arc is occurring in the plasma cavity if the absolute value of the difference exceeds a predetermined reflection coefficient threshold M times discontinuously within a predetermined period, where M is a positive integer of 1 or more.

[0051] Specifically, within a certain period of time (i.e., a predetermined period, the specific length of which can be determined according to the monitoring experience in actual applications or the statistical status of monitoring history data), a limited number of times M or less (including 1 time), discontinuously |Γ cur -Γ aver |>Γ th In this case, it can be determined that no arc is currently being generated within the plasma cavity.

[0052] In one embodiment, the predetermined analytical judgment condition may further optionally include determining that an arc has occurred in the plasma cavity if the absolute value of the difference exceeds the predetermined reflection coefficient threshold once.

[0053] Specifically, once |Γ cur -Γ aver |>Γ th In such cases, it can be determined that an arc has occurred within the plasma cavity.

[0054] In one embodiment, the predetermined analytical judgment condition may selectively include determining that an arc has occurred in the plasma cavity if the absolute value of the difference exceeds a predetermined reflection coefficient threshold for N consecutive times, where N is a positive integer of 2 or more.

[0055] Specifically, |Γ cur -Γ aver |>Γ th In such cases, it can be determined that an arc has occurred within the plasma cavity.

[0056] It should be explained that the above-mentioned predetermined analytical and judgment conditions may be used in combination, provided that no mutually exclusive conditions are combined.

[0057] In one embodiment, the detection period for arc detection sampling includes multiple detection periods in ascending order. The predetermined reflection coefficient threshold is either a manually set coefficient threshold or a coefficient threshold adaptively set by the system. The above method for suppressing arcs in a plasma cavity may further include the steps of: extending the detection period from the shortest detection period to the next longer detection period if the frequency of arc occurrence in the plasma cavity is lower than a set frequency threshold; otherwise, not changing the detection period, and adaptively increasing a coefficient threshold adaptively set by the system by a multiple or a constant value.

[0058] Specifically, a predetermined reflection coefficient threshold Γ th This may be manually set (for example, based on operational experience or monitoring history data) or adaptively set by the system. If the system adaptively sets it, first, the initial value Γ th Set |Γ cur -Γ aver |<Γ th An initial comparison process can be introduced, and the initial value Γ th This may be set manually, or Γ cur and Γ aver It may also be calculated from dynamic or historical data.

[0059] In actual monitoring, for example, the detection periods may be 8us, 16us, 32us, etc., but are not limited to these. According to a predetermined sequence of detection periods in ascending order, first set the shortest detection period, for example, 8us, and within this shortest detection period, |Γ cur -Γ aver |<Γ thThe frequency of arc occurrence is evaluated, and if the frequency of arc occurrence is lower than a predetermined frequency threshold, the detection period is extended to the next longer detection period, for example, 16us or 32us, and the coefficient threshold adaptively set by the system does not need to be changed. If the frequency of arc occurrence is higher than a predetermined frequency threshold within the shortest detection period, Γ th For example, increase the value of by a multiple or a constant value, or |Γ cur -Γ aver Get the dynamic maximum value of |, then double it or increase it by a constant value to adjust the Γ th Let's assume that.

[0060] The above steps enable adaptive adjustment of the system's coefficient threshold, further improving the accuracy of decisions regarding arc generation.

[0061] In one embodiment, the method for suppressing arcs in the plasma cavity further includes the step of causing the PID controller to maintain operation in a normal control state if it is determined, based on the comparison results, that no arcs are occurring in the plasma cavity. Here, the normal control state includes maintaining the current operating state of the control module, continuing arc detection sampling and obtaining the reflection coefficient in the plasma cavity, recording the average reflection coefficient in the current normal operating state, recording the operating parameters for the control module, recording the operating variable parameters of the unit device at the output terminal, and setting the time node in which it is currently operating normally as a restore node and continuously updating it.

[0062] Specifically, under the normal control state of the PID controller, the PID controller acquires the instantaneous gamma value and calculates its average value, and |Γ cur -Γ aver |<Γ thIf the system compares the values ​​and determines that no arc has occurred, it maintains the normal control state. At this time, the PID controller maintains the operation of the current control module and continuously monitors the gamma value. Simultaneously, it records the operating parameters at the current time node, including (a) the normal operating gamma average value, (b) the operating parameters of the PID controller's control module to the output terminal, and (c) the operating variable parameters of the unit device that outputs power at the output terminal. This time node is then designated as a restore node, and the data at this restore node is continuously updated in the normal control state.

[0063] In one embodiment, the process of instructing the state machine to lock the last operating parameter corresponding to the restoration node of the high-frequency power supply system in step S16 is as follows: The state machine instructs the last average reflection coefficient under normal operating conditions to lock, and instructs the control module to lock the operating parameters. This process may also include instructing the output terminals to lock the operating variable parameters of each unit device.

[0064] Specifically, when determining the occurrence of an arc, the PID controller is switched to a shut-off control state, and its state machine also switches to an operating state, instructing each module to lock the last operating parameter corresponding to the recovery node, for example, instructing the module for calculating the average gamma value to lock the average gamma value, instructing the control module of the PID controller to lock the operating parameters, and instructing the output terminal coupled to the plasma cavity to lock the operating variable parameters of the unit device. At the same time, the state machine instructs the PID controller to temporarily suspend monitoring of the gamma value for a certain period of X (including the voltage drop time + zero voltage + voltage rise).

[0065] As shown in Figure 3, a schematic diagram of ARC suppression at each stage, the entire ARC generation process can be divided into seven stages, A to G, and the meaning and processing method of each stage may be as shown in Table 1. By using the parameter lock control mechanism provided by the state machine, the system can be ensured to recover to a normal operating state as quickly as possible after the arc is eliminated.

[0066] [Table 1]

[0067] As shown in Figure 4, a schematic diagram of one ARC processing process, the entire process can be divided into two parts: a Gamma average value calculation and comparison part, and a PID storage and suspension part. This processing method enables high-precision detection and suppression of ARC, allows for the fastest possible recovery of system operation after arc extinguishing, and has low arc extinguishing costs.

[0068] It should be understood that while the steps in the flowcharts of Figures 1 and 4 are indicated sequentially by arrows, these steps are not necessarily performed in the order indicated by the arrows. Unless otherwise explicitly stated herein, the execution of these steps is not restricted by a strict order and may be performed in other orders. Furthermore, at least some of the steps in Figures 1 and 4 may include multiple substeps or stages, and these substeps or stages do not necessarily have to be executed and completed at the same time, but may be executed at different times, and the execution order of these substeps or stages does not necessarily have to follow this order, but may be executed alternately or in rotation with at least some of the other steps or the substeps or stages of other steps.

[0069] In one embodiment, as shown in Figure 5, an arc suppression device 100 in a plasma cavity is provided, which includes a detection sampling module 11, a coefficient comparison module 13, an arc extinguishing module 15, and an output recovery module 17. Here, the detection sampling module 11 is used to obtain the reflectance coefficient in the plasma cavity by arc detection sampling, and the reflectance coefficient includes the instantaneous reflectance coefficient and the average reflectance coefficient. The coefficient comparison module 13 is used to compare the absolute value of the difference between the instantaneous reflectance coefficient and the average reflectance coefficient with a predetermined reflectance coefficient threshold. The arc extinguishing module 15 is used to instruct the state machine to lock the last operating parameter corresponding to the recovery node of the high-frequency power supply system, pause arc detection sampling, and shut off the power output of the output terminal coupled to the plasma cavity by the control module of the PID controller, if it is determined based on the comparison result that an arc has occurred in the plasma cavity. The output recovery module 17 is used to instruct the control module of the PID controller to recover the power output of the output terminal and resume arc detection sampling based on the operating parameter after the arc in the plasma cavity has been removed.

[0070] The arc suppression device 100 in the plasma cavity acquires instantaneous and average reflection coefficients in the plasma cavity by arc detection sampling, and then compares them with a predetermined reflection coefficient threshold to accurately determine whether or not an arc has occurred in the plasma cavity. If it is determined that an arc has occurred in the plasma cavity, the state machine instructs the control module of the PID controller to lock the last operating parameter corresponding to the recovery node of the high-frequency power supply system, temporarily suspend arc detection sampling, and shut off the power output of the output terminal coupled to the plasma cavity, i.e., temporarily suspend the power output of the high-frequency power supply to the plasma cavity. After the arc in the plasma cavity is removed, the control module of the PID controller is instructed to restore the power output of the output terminal and restore arc detection sampling, i.e., restore the power output of the high-frequency power supply to the plasma cavity, based on the operating parameters. This achieves highly accurate suppression of arcs in the plasma cavity.

[0071] Compared to conventional methods, the above solution significantly improves the accuracy of determining whether or not an arc has occurred by using a comparison mechanism between the average reflection coefficient (which may also be called the average gamma value) and the critical value. If it is determined that an arc has occurred, the state machine instructs the system to lock the last operating parameter corresponding to the system's recovery node, temporarily suspend arc detection, and temporarily suspend power output. As a result, after the arc has been removed from the cavity, power output can be accurately and quickly restored based on the locked operating parameter, enabling highly accurate arc suppression processing within the cavity, reducing arc suppression costs, improving efficiency, and increasing adaptability.

[0072] In one embodiment, the process for determining whether or not an arc has occurred in the plasma cavity based on the comparison results includes determining whether or not an arc has occurred in the plasma cavity based on whether the absolute value of the difference is less than a predetermined reflection coefficient threshold and satisfies predetermined analytical judgment conditions.

[0073] In one embodiment, the predetermined analysis judgment condition includes determining that no arc is occurring in the plasma cavity if the absolute value of the difference is less than a predetermined reflection coefficient threshold for N consecutive times, where N is a positive integer of 2 or more.

[0074] In one embodiment, the predetermined analysis and judgment conditions include determining that no arc is occurring in the plasma cavity if the absolute value of the difference exceeds a predetermined reflection coefficient threshold M times discontinuously within a predetermined period, where M is a positive integer of 1 or more.

[0075] In one embodiment, the predetermined analysis and judgment conditions include determining that an arc has occurred in the plasma cavity if the absolute value of the difference exceeds a predetermined reflection coefficient threshold once.

[0076] In one embodiment, the predetermined analysis and judgment conditions include determining that an arc has occurred in the plasma cavity if the absolute value of the difference exceeds a predetermined reflection coefficient threshold for N consecutive times, where N is a positive integer of 2 or more.

[0077] In one embodiment, the detection period for arc detection sampling includes multiple detection periods in ascending order, the predetermined reflection coefficient threshold is a manually set coefficient threshold or a coefficient threshold adaptively set by the system, and the method further includes the steps of extending the detection period from the shortest detection period to the next longer detection period if the frequency of arc occurrence in the plasma cavity is lower than a set frequency threshold, and, if not, not changing the detection period and adaptively increasing the coefficient threshold adaptively set by the system by a multiple or a constant value.

[0078] In one embodiment, the method further includes the step of causing the PID controller to maintain operation in a normal control state if it is determined from the comparison results that no arc is occurring in the plasma cavity, wherein the normal control state includes maintaining the current operating state of the control module, continuing arc detection sampling and obtaining the reflectance coefficient in the plasma cavity, recording the average reflectance coefficient in the current normal operating state, recording the operating parameters for the control module, recording the operating variable parameters of the unit device at the output terminal, and setting the currently operating time node to a restore node and continuously updating it.

[0079] In one embodiment, the process of instructing a state machine to lock the last operating parameter corresponding to the restore node of a high-frequency power supply system includes instructing the state machine to lock the last average reflection coefficient under normal operating conditions, instructing a control module to lock the operating parameters, and instructing the output terminals to lock the operating variable parameters of each unit device.

[0080] In one embodiment, the step of obtaining the reflectance coefficient in the plasma cavity by arc detection sampling includes the step of obtaining the instantaneous reflectance coefficient by employing periodic, fixed-point sampling, and the step of calculating the average reflectance coefficient from all the instantaneous reflectance coefficients currently sampled, wherein each sampling, average value calculation, and threshold comparison are all synchronous multithreaded processes at single time intervals.

[0081] For specific limitations of the arc suppression device 100 in the plasma cavity, refer to the limitations of the arc suppression method in the plasma cavity described above, and a detailed explanation is omitted here. Each module in the arc suppression device 100 in the plasma cavity can be implemented in whole or in part by software, hardware, or a combination thereof. Each module may be built into or independent of the PID controller or processor in the high-frequency power supply system in hardware form, or it may be stored in the memory of the high-frequency power supply system in software form, so that the PID controller or processor can easily call and execute operations corresponding to each of the above modules.

[0082] In one embodiment, as shown in Figure 6, a high-frequency power supply system 200 is provided, which includes a high-frequency power supply 22, a PID controller 24, and a plasma cavity 26. The high-frequency power supply 22 is electrically connected to the plasma cavity 26 via the PID controller 24. The PID controller 24 is used to implement an arc suppression process step which includes the steps of: obtaining a reflection coefficient in the plasma cavity by arc detection sampling, wherein the reflection coefficient includes an instantaneous reflection coefficient and an average reflection coefficient; comparing the absolute value of the difference between the instantaneous reflection coefficient and the average reflection coefficient with a predetermined reflection coefficient threshold; if it is determined from the comparison result that an arc has occurred in the plasma cavity, locking the last operating parameter corresponding to the recovery node of the high-frequency power supply 22 system, temporarily suspending arc detection sampling, and shutting off the power output of the output terminal coupled to the plasma cavity; and after the arc in the plasma cavity has been removed, restoring the power output of the output terminal based on the operating parameter and restoring arc detection sampling.

[0083] For a specific and limited explanation of the functions realized by the PID controller 24 described above, it is understood that one can refer to the corresponding limited explanation of the arc suppression method in the plasma cavity described above, and therefore a detailed explanation is omitted here. The specific electrical connections between each component in the high-frequency power supply system 200 and their mechanical structures can be understood in the same way by referring to the electrical and mechanical structures of existing high-frequency power supply systems 22 in this art, and therefore a detailed explanation is omitted in this specification.

[0084] Figure 7 shows the structure of the ARC processing module divided by the functions to be implemented. The PID controller 24 can be divided into a control module that controls the output terminal coupled to the plasma cavity 26, and an ARC processing module as shown in Figure 7. The ARC processing module includes an average value calculation unit, a comparison unit, an ARC detection unit, and a state machine. The average value calculation unit can be used to calculate the instantaneous reflection coefficient from measurement information detected and sampled in real time and to calculate the corresponding average reflection coefficient. The comparison unit is |Γ cur -Γ aver | and Γ thIt can be used to perform a comparison. The ARC detection unit can be used to determine whether or not an arc has occurred in the cavity based on the comparison result. The state machine can be used to implement the corresponding instruction and control functions shown in the above embodiment.

[0085] As those skilled in the art will understand, Figures 6 and 7 are merely block diagrams of some product entities and functional structures related to the solution of this application, and do not specifically limit the high-frequency power supply system to which the solution of this application is applied. The specific high-frequency power supply system may include more or fewer components than those shown above, or may be a combination of some components, or may have a different component distribution, and can be determined specifically according to the type of actual high-frequency power supply system.

[0086] The high-frequency power supply system 200 acquires instantaneous and average reflection coefficients within the plasma cavity by arc detection sampling, and then compares them with a predetermined reflection coefficient threshold to accurately determine whether or not an arc has occurred within the plasma cavity. If it is determined that an arc has occurred within the plasma cavity, the system locks the last operating parameter corresponding to the recovery node of the high-frequency power supply system, pauses arc detection sampling, and instructs the control module of the PID controller 24 to shut off the power output of the output terminal coupled to the plasma cavity, i.e., to temporarily suspend the power output of the high-frequency power supply to the plasma cavity 26, via the state machine. After the arc in the plasma cavity is removed, the system instructs the control module of the PID controller 24 to restore the power output of the output terminal and restore arc detection sampling, i.e., to restore the power output of the high-frequency power supply to the plasma cavity 26, based on the operating parameters. This achieves highly accurate suppression of arcs within the plasma cavity.

[0087] Compared to conventional methods, the above solution significantly improves the accuracy of determining whether or not an arc has occurred by using a comparison mechanism between the average reflection coefficient (which may also be called the average gamma value) and the critical value. If it is determined that an arc has occurred, the state machine instructs the system to lock the last operating parameter corresponding to the system's recovery node, temporarily suspend arc detection, and temporarily suspend power output. As a result, after the arc has been removed from the cavity, power output can be accurately and quickly restored based on the locked operating parameter, enabling highly accurate arc suppression processing within the cavity, reducing arc suppression costs, improving efficiency, and increasing adaptability.

[0088] In one embodiment, a computer-readable storage medium is provided that stores a computer program which, when executed by a processor, performs the following steps: obtaining a reflectance coefficient in a plasma cavity by arc detection sampling, wherein the reflectance coefficient includes an instantaneous reflectance coefficient and an average reflectance coefficient; comparing the absolute value of the difference between the instantaneous reflectance coefficient and the average reflectance coefficient with a predetermined reflectance coefficient threshold; if it is determined based on the comparison result that an arc has occurred in the plasma cavity, instructing the state machine to lock the last operating parameter corresponding to the restore node of the high-frequency power supply system, suspend arc detection sampling, and shut off the power output of the output terminal coupled to the plasma cavity by the control module of the PID controller; and after the arc in the plasma cavity has been removed, instructing the control module of the PID controller to restore the power output of the output terminal and resume arc detection sampling based on the operating parameter.

[0089] In one embodiment, when a computer program is executed by a processor, additional steps or substeps added to each embodiment of the method for suppressing arcs in the plasma cavity may be implemented.

[0090] It will be apparent to those skilled in the art that all or part of the flow in the methods of the above embodiments can be implemented by the relevant hardware by issuing instructions to the relevant hardware via a computer program, which may be stored in a non-volatile computer-readable storage medium and, when executed, can execute the flow of each embodiment of the above embodiments. In this, all references to memory, storage devices, databases or other media used in each embodiment provided in this application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. While RAM can be obtained in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), extended SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), memory bus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), it is not limited to these.

[0091] The technical features of the above embodiments can be combined in any way, and for the sake of brevity, not all possible combinations of the technical features in the above embodiments have been described. However, these combinations of technical features should be considered to fall within the scope described herein, as long as they are not contradictory.

[0092] The above embodiments represent only a few embodiments of this application, and although the description is specific and detailed, it should not be understood as limiting the scope of the claims. It should be noted that a person skilled in the art may make various modifications and improvements without departing from the concept of this application, all of which fall within the scope of protection of this application. Therefore, the scope of protection of this application shall be in accordance with the attached claims.

Claims

1. The steps include obtaining the instantaneous reflectance coefficient in the plasma cavity by arc detection sampling and updating the average reflectance coefficient using the said instantaneous reflectance coefficient, The steps include comparing the absolute value of the difference between the instantaneous reflection coefficient and the average reflection coefficient with a predetermined reflection coefficient threshold, If the absolute value of the difference is consistently below the predetermined reflection coefficient threshold for 2 or more positive integer N samplings, and if it exceeds the predetermined reflection coefficient threshold for 1 or more positive integer M samplings but is discontinuous within a predetermined period, then it is determined that no arc is occurring in the plasma cavity, and the PID controller is instructed to maintain normal control operation. If the absolute value of the difference exceeds the predetermined reflection coefficient threshold in a single sampling, or if it exceeds the predetermined reflection coefficient threshold consecutively in two or more positive integer N samplings, it is determined that an arc has occurred in the plasma cavity, the last operating parameter corresponding to the restoration node of the high-frequency power supply system is locked, the arc detection sampling is temporarily suspended, and the power output of the output terminal coupled to the plasma cavity is shut off by the control module of the PID controller. Steps instructed by the state machine, The method is characterized by including the step of, after the arc in the plasma cavity has been removed, instructing the control module of the PID controller to restore the power output at the output terminal and restore the arc detection sampling based on the operating parameters, A method for suppressing arcs in a plasma cavity.

2. The detection period for the arc detection sampling includes multiple detection periods in ascending order, and the predetermined reflection coefficient threshold is a coefficient threshold set manually or a coefficient threshold set adaptively by the system. The aforementioned method, If the frequency of arc generation in the plasma cavity from the shortest detection period is lower than a set frequency threshold, the detection period is extended to the next longer detection period. Otherwise, the method for suppressing an arc in a plasma cavity according to claim 1, further comprising the step of adaptively increasing a coefficient threshold adaptively set by the system by a multiple or a constant value without changing the detection period.

3. The normal control state is Maintaining the current operating state of the control module, Continue arc detection sampling to obtain the reflectance coefficient within the plasma cavity, To record the average reflection coefficient under the current normal operating conditions, Recording the operating parameters for the control module, The method for suppressing an arc in a plasma cavity according to claim 1, characterized by including recording the operating variable parameters of the unit device at the output terminal, setting the currently operating time node as a restore node, and continuously updating it.

4. The process of instructing the state machine to lock the last operating parameter corresponding to the restoration node of the high-frequency power supply system is: The method for suppressing an arc in a plasma cavity according to claim 3, characterized in that a state machine is instructed to lock the last average reflection coefficient under normal operating conditions, instructs the control module to lock the operating parameters, and instructs the output terminals to lock the operating variable parameters of each unit device.

5. The step of obtaining the reflectance coefficient in the plasma cavity by arc detection sampling is: The steps include obtaining the instantaneous reflection coefficient by employing periodic, fixed-point sampling, A method for suppressing an arc in a plasma cavity according to claim 1, comprising the step of calculating the average reflection coefficient using all currently sampled instantaneous reflection coefficients, wherein each sampling, average calculation, and threshold comparison are all synchronous multithreaded processes at single time intervals.

6. A detection sampling module for acquiring the instantaneous reflectance coefficient in the plasma cavity by arc detection sampling and updating the average reflectance coefficient using the said instantaneous reflectance coefficient, A coefficient comparison module for comparing the absolute value of the difference between the instantaneous reflection coefficient and the average reflection coefficient with a predetermined reflection coefficient threshold, If the absolute value of the difference is consistently below the predetermined reflection coefficient threshold for 2 or more positive integer N samplings, and if it exceeds the predetermined reflection coefficient threshold for 1 or more positive integer M samplings but is discontinuous within a predetermined period, then it is determined that no arc is occurring in the plasma cavity, and the PID controller is instructed to maintain normal control operation. If the absolute value of the difference exceeds the predetermined reflection coefficient threshold in a single sampling, or if it exceeds the predetermined reflection coefficient threshold consecutively in two or more positive integer N samplings, it is determined that an arc has occurred in the plasma cavity, the last operating parameter corresponding to the restoration node of the high-frequency power supply system is locked, the arc detection sampling is temporarily suspended, and the power output of the output terminal coupled to the plasma cavity is shut off by the control module of the PID controller. An arc extinguishing module for control by a state machine, The system is characterized by including an output recovery module for instructing the control module of the PID controller to recover the power output at the output terminal and recover the arc detection sampling based on the operating parameters after the arc in the plasma cavity has been removed, Arc suppression device inside the plasma cavity.

7. The system includes a high-frequency power supply, a PID controller, and a plasma cavity, wherein the high-frequency power supply is electrically connected to the plasma cavity via the PID controller. The PID controller is, The steps include obtaining the instantaneous reflectance coefficient in the plasma cavity by arc detection sampling and updating the average reflectance coefficient using the said instantaneous reflectance coefficient, The steps include comparing the absolute value of the difference between the instantaneous reflection coefficient and the average reflection coefficient with a predetermined reflection coefficient threshold, If the absolute value of the difference is consistently below the predetermined reflection coefficient threshold for 2 or more positive integer N samplings, and if it exceeds the predetermined reflection coefficient threshold for 1 or more positive integer M samplings but is discontinuous within a predetermined period, then it is determined that no arc is occurring in the plasma cavity, and the PID controller is instructed to maintain normal control operation. If the absolute value of the difference exceeds the predetermined reflection coefficient threshold in one sampling, or if it exceeds the predetermined reflection coefficient threshold consecutively in two or more positive integer N samplings, it is determined that an arc has occurred in the plasma cavity, and the last operating parameter corresponding to the restoration node of the high-frequency power supply system is locked, the arc detection sampling is temporarily suspended, and the power output of the output terminal coupled to the plasma cavity is shut off. This is used to implement an arc suppression process step which includes, after the arc in the plasma cavity has been removed, the power output at the output terminal and the arc detection sampling based on the operating parameters. High-frequency power supply system.

8. A computer-readable storage medium in which a computer program is stored, When the computer program is executed by the processor, the steps of the method for suppressing an arc in a plasma cavity according to any one of claims 1 to 7 are realized. Computer-readable storage medium.

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