Methods for operating electronic systems and electronic systems

Abstract

A method for operating an electronic system comprising a radio frequency (RF) matching circuit, wherein the RF matching circuit comprises a plurality of electronic components, at least one of which is a variable reactance element, and the method comprises monitoring activity information of the at least one variable reactance element and determining a predicted lifetime from the activity information.

Description

TECHNICAL FIELD

[0001] The present invention relates to a method for operating an electronic system comprising a radio frequency (RF) matching circuit. In particular, the present invention relates to a method for operating an electronic system in plasma applications. Furthermore, the present invention relates to an electronic system comprising an RF matching circuit, an RF power supply, a plasma system and a storage medium. BACKGROUND ART

[0002] Plasma applications typically include a plasma chamber in which plasma is generated for surface processing and treatment such as plasma etching or plasma deposition. For example, the manufacture of modern semiconductor chips, flat panel displays and photovoltaic power generation panels relies heavily on plasma etching and plasma deposition. To generate plasma in the plasma chamber, gas is partially ionized by applying direct or alternating current power, and in many applications, it is preferable that the power is supplied as high-frequency power. For this purpose, the plasma chamber is connected to an electronic system. The electronic system comprises a high-power RF power supply that provides an RF signal preferably having a frequency of 0.3 MHz to 300 MHz and a power of preferably 0.05 kW to 50 kW. Advanced plasma etching and deposition processes may require pulsing the RF power in a repetitive pulsed mode characterized by various pulse levels, duty cycles and power levels.

[0003] Since the impedance of the plasma in the plasma chamber is variable, an RF matching circuit is provided between the RF power supply and the plasma chamber to match the output impedance of the electronic system to the impedance of the plasma, which is a dynamically time-varying load for the electronic system. Thereby, the RF matching circuit is a critical component in the electronic system, which prevents excessive reflected power from the plasma system to the RF power supply due to impedance mismatch, thereby protecting the electronic components of the RF power supply such as power amplifiers.

[0004] To match the impedance of an electronic system, an RF matching circuit typically includes one or more variable reactance elements that are mechanically driven to change the reactance, or impedance. Due to their mechanical operation, the variable reactance elements in an RF matching circuit have a limited lifespan. Failure of a variable reactance element can render the electronic system, and even the entire plasma system, inoperable. Furthermore, a sudden failure of a variable reactance element in operation can severely affect the electronic components of the RF power supply, potentially leading to the destruction or at least damage of the RF power supply.

[0005] In this invention, the terms maintenance or service mean any activities performed, for example, in a manufacturing facility, to ensure that the electronic system functions properly for its intended purpose.

[0006] Unscheduled maintenance is performed after an unexpected failure occurs in an electronic system and often involves repairing or replacing the faulty component.

[0007] Preventive maintenance is scheduled periodically after a specific time interval or after a certain number of usage cycles of an electronic system. Preventive maintenance may include calibration of precision components and planned replacement of components before the end of their service life, thereby preventing components from failing due to normal wear and tear while the electronic system is being used for manufacturing purposes.

[0008] In manufacturing environments, it is essential to minimize unexpected equipment downtime due to breakdowns or unscheduled maintenance. Typically, unscheduled maintenance can be avoided by defining appropriate service or maintenance intervals for recalibration and proactively replacing parts nearing the end of their expected lifespan, particularly mechanical components.

[0009] Therefore, mechanical components such as variable reactance elements in RF matching circuits should undergo regular preventative maintenance and be replaced before they negatively impact the electronic system. However, this can lead to unnecessary costs because the service intervals are set too short preventatively.

[0010] For example, in plasma systems, even technically identical systems can experience completely different wear patterns on electronic system components due to variations in the recipes used in the process cycle. Process parameters such as plasma impedance, RF power level, gas pressure, gas flow rate, process gas and process gas mixture, and electronic system recipe preset conditions influence the amount of RF power consumed within the RF matching circuit, causing component temperatures to rise or fall. In particular, adjustable reactance components may be subjected to more or less stressful conditions.

[0011] US20220334197A1 describes an electrical system comprising a matching circuit with a variable capacitor, a controller, and a lifetime consumption module. Based on telemetry data and environmental data of the capacitor in operation, the lifetime consumption module reports an indicator of the lifetime of at least one capacitor. In this publication, only environmental data (e.g., ambient temperature) is used to determine the lifetime, apart from telemetry data. However, other parameters that significantly affect the lifetime, particularly the actual temperature of individual components of the capacitor, are not considered. Furthermore, while this approach can determine the lifetime of a capacitor, this publication does not describe how to determine the remaining usable time of the capacitor, which will depend on future usage. As a result, it is not possible to plan for preventive maintenance or replacement of the capacitor.

[0012] Therefore, an object of the present invention is to provide a method for making electronic systems operate more predictably by using a method for more accurately determining the remaining lifespan of components. [Overview of the project] [Problems that the invention aims to solve]

[0013] This problem is solved by the method according to claim 1, the electronic system according to claim 15, the plasma system according to claim 16, and the non-temporary storage medium according to claim 17. [Means for solving the problem]

[0014] In a first embodiment, a method for operating an electronic system is provided. The electronic system includes a radio frequency (RF) matching circuit to match the impedance of the electronic system's output to a load such as a plasma chamber having a variable impedance. In particular, the electronic system may further include an RF power supply to provide a high-power RF signal having a frequency preferably between 0.3 MHz and 300 MHz and a power preferably between 0.05 kW and 50 kW. The RF matching circuit comprises several electronic components, at least one of which is a variable reactance element. Here, the variable reactance element provides a mechanically adjustable impedance, and the impedance at the output of the electronic system can be matched by mechanically adjusting the variable reactance element. The method includes monitoring activity information of at least one variable reactance element and determining a predicted lifetime from the activity information.

[0015] Therefore, according to the present invention, activity information of at least one variable reactance element is monitored and detected. Based on the actual behavior of at least one variable reactance element, a predicted lifespan is determined, which is used to assess whether recalibration, repair, or replacement is necessary. Thus, preventive maintenance can be performed according to the actual usage of the variable reactance element. For example, if an RF matching circuit is connected to a fluctuating load and impedance adjustment is frequently required within a short period of time, the lifespan of the variable reactance element may be consumed in a shorter time compared to when the load is more constant or when the overall electronic system is used less frequently. Thus, service intervals can be specifically adjusted to suit the needs and usage of the electronic system without the risk of failure due to unintentionally exceeding the lifespan of at least one variable reactance element.

[0016] Preferably, the method further includes monitoring at least one operating parameter of the electronic system (the operating parameter may include one or more of current, RF power level, RF frequency, pulse information, and duty cycle), determining the temperature of the electronic system from at least one operating parameter, and determining the predicted lifetime from the activity information and the determined temperature.

[0017] Therefore, the predicted lifetime is determined from a combination of monitored activity information and determined temperature. However, temperature may not be directly measured or may not be directly measured. Instead, at least one operating parameter of the electronic system is monitored, and the temperature of the electronic system or a component of the electronic system is determined from this at least one operating parameter. Since temperature has a significant impact on the lifetime of electronic components and variable reactance elements, detailed information about the temperature of the electronic system improves the accuracy of the predicted lifetime. However, temperatures in different components or locations within the electronic system may have different effects on lifetime. Instead of measuring temperature at multiple locations within the electronic system, the temperature can be determined directly from at least one operating parameter that is already known during the operation of the electronic system. Therefore, the complexity of the electronic system hardware can be kept simple, while at the same time, detailed information about temperature and the electronic system can be obtained from at least one operating parameter.

[0018] Preferably, the method further includes monitoring the RF frequency during operation of the electronic system, and determining a predicted lifetime from the activity information, the RF frequency during operation, and preferably the determined temperature.

[0019] Therefore, the predicted lifetime is determined from the activity information and the RF frequency during operation generated by the electronic system. In particular, when the temperature is determined as described above, the predicted lifetime is determined from the combination of the activity information, the RF frequency during operation, and the determined temperature. Since the RF frequency on which the electronic system operates affects the lifetime of the variable reactance element, considering the RF frequency during operation improves the accuracy of the predicted lifetime.

[0020] Preferably, a warning signal is generated when the predicted remaining life falls below a predetermined threshold. Here, the warning signal may be a visual signal such as a warning lamp, an audible signal, a message displayed by an electronic system, or a message provided to the user interface or control unit of an electronic system. Alternatively, or in addition to the above, the warning signal may be a digital status signal transmitted to a remote server or device. Thus, when a warning signal is generated, the user or manufacturer of the electronic system can plan and perform service in a timely manner and proactively plan maintenance before failure occurs.

[0021] Preferably, the predicted lifetime is displayed and / or transmitted to a remote server. Therefore, continuous monitoring of the electronic system, particularly the predicted lifetime, is possible directly within the electronic system, for example, in the control unit or through the control unit's user interface, or the predicted lifetime can be displayed, controlled, and further processed on a remote server. In particular, the remote server may receive predicted lifetimes for multiple different electronic systems and their RF matching circuits.

[0022] Preferably, the variable reactance element is one of a mechanically adjustable gas capacitor, a mechanically adjustable vacuum capacitor, and a mechanically adjustable inductor. Here, the mechanically adjustable inductor may include a coil containing ferrite, the coil having a sliding tap contact for adjusting the number of turns of the inductor. Alternatively, the relative position between the coil and the ferrite can be mechanically adjusted. The mechanically adjustable gas or vacuum capacitor includes two electrodes placed in a gas or vacuum, the gas or vacuum acting as a dielectric material. At least one of the electrodes is movable so that the capacitance can be adjusted by adjusting the distance or overlapping area between the two electrodes in the gas capacitor or vacuum capacitor.

[0023] Preferably, the activity information is the mechanical adjustment of the variable reactance element. In particular, the activity information is the cumulative distance traveled, which is can be represented by JPEG2026536510000002.jpg911, where x i represents the movement distance from the first position to the second position.

[0024] Preferably, the at least one operating parameter includes a current of the electronic system, and particularly includes a current in at least one of the plurality of electronic components. In particular, the current may be a current at the output of an impedance matching circuit, a current in a variable reactance element, or a current detected by a detection circuit such as a VI voltage-current sensor. In particular, the operating parameter may be a time integral parameter. In the example of the current I(t), the considered operating parameter, where t0 is the current time, is may be JPEG2026536510000003.jpg918, or may be the cumulative duration of current within a specific range or above a specific threshold.

[0025] Preferably, determining the temperature of the electronic system from the at least one operating parameter includes at least one of the following. - pre-determining a lookup table that provides a correspondence between the at least one operating parameter and the temperature, and searching for the temperature corresponding to each respective operating parameter in the lookup table during operation, - pre-determining a model of the variable reactance element and / or any other electronic component that provides a functional relationship between the at least one operating parameter and the temperature, and determining the temperature using the functional relationship during operation, - pre-determining a model of the electronic system that includes at least one variable reactance, further components, and parasitic inductance, capacitance and resistance, providing a functional relationship between the value of the variable reactance and the at least one operating parameter and the temperature, and determining the temperature using the functional relationship during operation, and - training a machine learning algorithm to determine the temperature from the at least one operating parameter, and determining the temperature using the trained machine learning algorithm during operation.

[0026] Preferably, the temperature includes one or more of the temperature of the variable reactance element, the temperature of any other electronic component of the RF matching circuit, and the air temperature within the electronic system. Here, at least one of these temperatures may be determined as a temperature from at least one operating parameter, or a combination of these temperatures may be determined from at least one operating parameter. In particular, each temperature can be determined, as described above, by either a look-up table, a model providing a functional relationship, or a machine learning algorithm that correlates at least one operating parameter with one of these temperatures.

[0027] Preferably, the predicted lifetime includes the predicted number of remaining process cycles, wherein the predicted lifetime is calculated from the predicted number of remaining process cycles and the time between two consecutive process cycles. In particular, the predicted lifetime is calculated by multiplying the predicted number of remaining process cycles by the time between two consecutive process cycles. Alternatively, the predicted lifetime is determined by multiplying the predicted number of remaining process cycles by the average time between two consecutive process cycles.

[0028] Preferably, when the electronic system operates in two or more different process cycles, the predicted lifetime is determined by a combination of the predicted number of remaining process cycles for each different process cycle and the occurrence frequency of each different process cycle. Thus, for example, when two different cycles are performed, the lifetime is determined by the predicted number of remaining process cycles of the first process and the occurrence time of the first process cycle, and the predicted number of remaining process cycles of the second process cycle and the occurrence time of the second process cycle.

[0029] Preferably, the process cycle and the time between two process cycles are determined by pattern recognition. In particular, when repeating the processing steps of a process cycle, the positions of at least one variable reactance element may be the same or at least similar. Here, when detecting the pattern of the positions of the variable reactance elements, the repeatability characteristics at the positions of the variable reactance elements can be detected by pattern recognition that identifies the time between two consecutive process cycles.

[0030] Preferably, determining the predicted lifetime includes at least one of the following: - Pre-determine a lookup table that provides activity information and, preferably, the correspondence between temperature and / or RF frequency and predicted lifetime, and during operation, retrieve each piece of activity information and, preferably, the predicted lifetime for temperature and / or RF frequency within the lookup table. - Predetermine the functional relationship between activity information, preferably temperature and / or RF frequency, and predicted lifetime, and use the functional relationship to determine the predicted lifetime during operation, and - Train a machine learning algorithm to determine the predicted lifetime from activity information, preferably along with temperature and / or RF frequency, and use the trained machine learning algorithm to determine the predicted lifetime during operation.

[0031] In another embodiment, the present invention relates to an electronic system comprising an RF matching circuit, wherein the RF matching circuit comprises a plurality of electronic components, at least one of which is a variable reactance element. Furthermore, the electronic system comprises a control unit, which may include a processor, and is configured to perform the steps of the method described above.

[0032] Preferably, the electronic system includes an RF power supply to generate a high-power RF signal supplied to a load, where the load may be a plasma chamber for surface treatment and processing.

[0033] In another embodiment, the present invention relates to a plasma system comprising the aforementioned electronic system and a plasma chamber connected to the electronic system for generating plasma.

[0034] In another aspect of the present invention, a non-transient tangible processor-readable storage medium encoded with processor-readable instructions is provided, and when these instructions are executed by the processor, the control unit performs the steps of the method described above. [Brief explanation of the drawing]

[0035] The present invention will be described in more detail below with reference to the accompanying drawings.

[0036] [Figure 1] This is a schematic diagram of the plasma system according to the present invention. [Figure 2] This is a flowchart of the method according to the present invention. [Figure 3] This is a flowchart of the method according to the present invention. [Figure 4] This is a schematic diagram of an embodiment according to the present invention. [Figure 5A] This is an exemplary representation of activity information. [Figure 5B] This is an exemplary representation of activity information. [Figure 6] This is a representation of the predicted lifetime according to the present invention. [Figure 7] This is a schematic diagram of the process cycle of the plasma system according to the present invention. [Figure 8A] This is an example of single-plasma processing where the matching circuit starts from a capacitor preset position that requires a large movement to reach the adjusted position. [Figure 8B] This is an example of repetitive plasma processing where a matching circuit uses a capacitor preset position that requires a large movement to reach the adjusted position. [Figure 9A] This is a second example of single-plasma processing where the matching circuit starts from a capacitor preset position that requires a large movement to reach the adjusted position. [Figure 9B]This is a second example of repetitive plasma processing where a matching circuit uses a capacitor preset position that requires a large movement to reach the adjusted position. [Figure 10A] This is an example of single-plasma processing where the matching circuit starts from an improved capacitor position with less movement to reach the adjusted position. [Figure 10B] This is an example of repeated plasma processing where the matching circuit starts from an improved capacitor position with less movement to reach the adjusted position. [Figure 11A] This is an example of single-plasma processing where the matching circuit starts from an optimized capacitor position with minimal movement to reach the tuned position. [Figure 11B] This is an example of repeated plasma processing where a matching circuit starts from an optimized capacitor position with minimal movement to reach the adjusted position. [Figure 12] This is a typical relationship between the amount of capacitor displacement (percentage of the nominal range) and the average number of capacitor cycles or tuning cycles until the bellows fail (from Comet Plasma Control Technologies Service Bulletin SB-56). [Modes for carrying out the invention]

[0037] Referring to Figure 1, the plasma system 10 according to the present invention includes an electronic system 11, which is connected to a plasma chamber 16 to generate plasma within the plasma chamber 16, particularly for surface treatment and processing for semiconductors. Here, the electronic system 11 includes a high-power RF power supply 12 that provides a high-power RF signal having a frequency between 0.3 MHz and 300 MHz and a power between 0.05 kW and 50 kW. An RF matching circuit 14 is connected between the RF power supply 12 and the plasma chamber 16 to match the output impedance of the electronic system 11 with the variable impedance of the plasma in the plasma chamber 16. The RF matching circuit 14 matches the impedance of the electronic system 11 with the impedance of the plasma in the plasma chamber 16. Thus, the RF matching circuit 14 includes at least one variable reactance element. The variable reactance element may be a mechanically adjustable gas capacitor, a mechanically adjustable vacuum capacitor, or a mechanically adjustable inductor. Mechanically adjustable gas capacitors and mechanically adjustable vacuum capacitors include two electrodes that are movable such that the distance or overlap area between the electrodes is variable in order to adjust the capacitance of the mechanically adjustable gas capacitor and mechanically adjustable vacuum capacitor. Here, gas is used as the dielectric material in the mechanically adjustable gas capacitor and vacuum is used as the dielectric material in the mechanically adjustable vacuum capacitor. Here, the mechanically adjustable inductor may include a coil containing ferrite, the coil having a sliding tap contact for adjusting the number of turns of the inductor. Alternatively, the relative position between the coil and the ferrite can be mechanically adjusted. Thus, by mechanically adjusting the variable reactance element, the impedance of the electronic system 11 can be adjusted to match the impedance of the plasma in the plasma chamber 16.

[0038] The following refers to Figure 2, which illustrates how to operate the electronic system 11.

[0039] In step S01, activity information of at least one variable reactance element is monitored.

[0040] In step S02, the predicted lifetime of at least one variable reactance element is determined from the activity information.

[0041] Therefore, activity information of at least one variable reactance element is monitored and used to predict its lifetime. Here, as described above, the activity information may be the movement of one of the electrodes of a mechanically adjustable gas capacitor or a mechanically adjustable vacuum capacitor, the movement of ferrite relative to the coil in a mechanically adjustable inductor, or the position of the tap contact of the coil in a mechanically adjustable inductor. Here, the predicted remaining lifetime is illustrated in Figure 6, where a threshold 18 is shown. If the predicted lifetime falls below a predetermined threshold 18, a warning signal may be generated. Here, the warning signal may be a visual signal such as a warning lamp, an audible signal, or a message displayed by the electronic system, or a message provided to the user interface of the electronic system or the control unit of the electronic system. Alternatively, or in addition, the warning signal may be a digital status signal transmitted to a remote server or device. Therefore, when a warning signal is generated, the user of the electronic system or the manufacturer of the semiconductors processed by the electronic system can plan and perform maintenance in a timely manner and plan maintenance in advance before failure occurs.

[0042] Furthermore, the predicted lifetime may be displayed and / or transmitted to a remote server. Thus, continuous monitoring of the electronic system, particularly the predicted lifetime, is possible directly within the electronic system, for example, in the control unit or through the control unit's user interface, or the predicted lifetime can be displayed, controlled, and further processed on a remote server. In particular, the remote server may receive the predicted lifetimes of multiple different electronic systems and their RF matching circuits.

[0043] Preferably, steps S01 and S02 in Figure 2 are repeated continuously or at predetermined time intervals, for example every hour, every 10 minutes, every minute, every 30 seconds, every 5 seconds, in order to continuously determine the predicted lifetime based on the actual operating state of the electronic system.

[0044] Here, we refer to Figure 3, which shows a flowchart of the method according to the present invention. In addition to the method shown in Figure 2, in step S03, at least one operating parameter of the electronic system is monitored. Here, the at least one operating parameter is one or more currents of the electronic system, and in particular may be a current in at least one of a plurality of electronic components. In particular, the current may be a current at the output of an impedance matching circuit, a current in a variable reactance element, or a current detected by a detection circuit such as a VI voltage current sensor. In particular, the operating parameter may be a time integral parameter. In the example of current I(t), the operating parameter considered is, with t0 as the current time, It may be JPEG2026536510000004.jpg918, or it may be the cumulative duration of current within a certain range or above a certain threshold.

[0045] In step S031, the temperature of the electronic system is determined from at least one operating parameter. Thus, according to the present invention, a known operating parameter is used to determine the temperature of the electronic system. Here, the temperature of the electronic system may include the temperature of a variable reactance element, the temperature of any other electronic component, or the air temperature within the electronic system. One, more, or all of these temperatures affect the predicted lifetime, and considering them improves the accuracy of the predicted lifetime. Thus, in step S02', the predicted lifetime is determined from the combination of activity information and the determined temperature.

[0046] Refer to Figure 4, which illustrates the method according to the present invention. In the example in Figure 4, activity information, operating parameters, and RF frequency are depicted. However, it should be understood that lifetime prediction may alternatively be based on activity information, a combination of activity information and operating parameters, or activity information and RF frequency. From the operating parameters, perhaps taking the RF frequency into consideration, the temperature is determined. Here, the temperature determination can be performed by a predetermined lookup table that provides a correspondence between each operating parameter and temperature, and the temperature can be referenced for each operating parameter during operation. The lookup table may vary depending on the RF frequency. Alternatively, a predetermined model of a variable reactance element and / or any other electronic component is provided, establishing a functional relationship between at least one operating parameter and temperature, and during operation, that functional relationship is used to determine the temperature. In particular, the model may be based on the material properties and geometry of all subcomponents of the electronic system, including the heat exchange capability of the subcomponents with the surrounding structure, in particular the heat exchange capability of the variable reactance element. The mechanical design of the variable reactance element may be a FEM model that is calculated once to obtain a functional relationship between at least one operating parameter and temperature. Alternatively, a machine learning algorithm is trained to determine the correspondence between temperature and at least one operating parameter. The trained machine learning algorithm is then used to determine the temperature from the current operating parameter.

[0047] Activity information is illustrated in Figures 5A and 5B. Here, Figure 5A shows the position of the variable reactance element at different time points t, and during operation, the position of, for example, the electrodes of the variable reactance element is depicted. Figure 5B shows cumulative activity information that provides the cumulative displacement of the variable reactance element, such as the electrodes of the variable reactance element.

[0048] Referring again to Figure 4, activity information, temperature, and, in the example of Figure 4, optional RF frequency are also considered (shown by dashed lines) for lifetime prediction. Here, the predicted lifetime is determined according to a predetermined lookup table that provides a relationship between the activity information and the predicted lifetime, and during operation, the predicted lifetime is referenced in the predetermined lookup table for each piece of activity information. If more information is considered, such as temperature and RF frequency, as in the example of Figure 4, the lookup table can provide a relationship between the activity information, temperature, and RF frequency so that the predicted lifetime can be referenced for each piece of activity information, temperature, and RF frequency. Alternatively, a functional relationship is provided between the activity information and the predicted lifetime. This functional relationship may be a fitting function to experimental data, or it may be a pre-calculated functional relationship based on historical data of the measured lifetime of the variable reactance element during lifetime testing. During operation, the functional relationship is used to determine the predicted lifetime from the activity information. As in the example of Figure 4, additional information such as temperature and RF frequency, temperature only, or RF frequency only are also considered in the functional relationship to improve the accuracy of the predicted lifetime.

[0049] Alternatively, a machine learning algorithm may be trained to determine the predicted lifetime from activity information, and during operation, the trained machine learning algorithm may be used to determine the predicted lifetime. The machine learning algorithm may be trained based on historical lifetime data of the variable reactance element, historical data on the operation of similar electronic systems, etc. As shown in the example in Figure 4, additional information such as temperature and RF frequency, or temperature only, or RF frequency only, may also be considered in the machine learning algorithm to improve the accuracy of the predicted lifetime.

[0050] Based on the predicted lifespan, the remaining lifespan may be calculated based on the predicted number of remaining process cycles and the time or average time between consecutive process cycles. Here, process cycles may be identified by pattern recognition based on monitored activity information. Since the process is similar from cycle to cycle for the same process, the activity information in consecutive process cycles is also the same or at least similar. Here, the remaining lifespan may be calculated, for example, by multiplying the predicted number of remaining process cycles by the average time between two consecutive process cycles.

[0051] Referring here to Figure 7, if different processes are performed by the plasma system, according to the present invention, the predicted number of remaining process cycles is determined for each process P1, P2. The remaining lifetime is then calculated based on the number of occurrences of each process P1 and process P2 and the time between them, as illustrated in Figure 7.

[0052] Therefore, the present invention provides a reliable method for determining the remaining lifespan.

[0053] [First example demonstrating the advantages of the present invention] In semiconductor manufacturing, matched circuits typically operate repeatedly in the same plasma treatment or a series of plasma treatments. Based on a cumulative record of activity data, the lifespan can be determined. Furthermore, by using pattern recognition on the activity data, different processes can be identified, and their respective lengths can be determined. This information allows for the calculation of the lifespan consumed per process cycle, the number of remaining process cycles, and the expected time to end the lifespan.

[0054] However, this procedure can be easily adapted to new usage profiles of the matching circuit, for example, when a modified process or an entirely new process is introduced.

[0055] The electronic system may be configured to automatically detect such new process and usage profile changes, for example, changes in the frequency of different known processes. Based on the determined new usage profile, the remaining life can be recalculated, and preventive maintenance can be rescheduled accordingly.

[0056] [Second example demonstrating the advantages of the present invention] When users of an electronic system perform the setup of a specific process, they have various degrees of freedom in setting appropriate starting conditions for reliable plasma ignition and rapid adjustment to a steady state after ignition. Typically, the matching circuit operates in automatic mode, meaning that the control of the matching circuit is performed according to an automatic algorithm that finds the optimal reactance value to achieve optimal matching. In an ideal scenario, the reactance moves directly from the preset position to the final value where the reflected power from the plasma is nearly zero, as shown in Figures 8A and 8B. However, plasma ignition is a highly dynamic process, and the plasma impedance changes while the matching circuit optimizes the variable reactance value and more RF power is supplied to the plasma. Therefore, it is quite possible that the capacitor will move back and forth several times until it reaches the optimal position where the reflected power is minimized. By optimizing the starting or preset position of the variable reactance element before the plasma is ignited, unnecessary mechanical movement of the variable reactance element can be minimized. Furthermore, by gradually increasing the RF power to the target value, smooth operation of the variable reactance is possible, resulting in the advantage of extending its lifespan and the time until the next maintenance.

[0057] An example of the present invention's application is determining the lifetime of an RF matching circuit for a specific plasma processing configuration. For this purpose, the RF matching circuit can be configured to monitor the movement of the variable reactance in the plasma processing and calculate and display the expected number of process cycles until the end of the matching circuit's lifespan. By repeating this procedure for various starting conditions and obtaining the predicted maximum number of process cycles, the user can select the optimal starting conditions that maximize the lifetime of the matching circuit and variable reactance elements.

[0058] Referring to Figures 8A, 9A, 10A, and 11A, examples of plasma processing initiation are shown, where the plasma is ignited by turning on the forward RF power "Pfwd" at time 0 seconds, and the matching circuit, i.e., the positions of two variable reactances or capacitors, are automatically adjusted to the tuned position where the reflected power is minimized from different preset positions. The load impedance of the fully ignited plasma, defined by the RF power, pressure, gas mixture, and gas flow rate, is identical in all four examples. Therefore, even when starting from four different presets, as shown in the examples in Figures 8A, 9A, 10A, and 11A, the plasma ignition and the capacitor positions after adjustment are identical in all four cases. However, depending on the preset positions of the variable reactances or capacitors, the time to reach a steady plasma state may be longer or shorter. If the reflected power "Prefl" is too high when the RF power is turned on, the RF power supply may limit the output power "Pfwd" to a safe level, as seen in Figures 8A and 9A. The RF power "Pfwd" can only be increased to a predetermined value if the reflected power "Prefl" is reduced during tuning. Figures 8A and 9A show plasma ignition from two suboptimal preset conditions where both capacitors must move significantly within their nominal range (20-55%) and the tuning time is 1-2 seconds. Figure 10A shows plasma ignition from a more favorable preset position, from which a steady state is reached in less than 1 second, and the capacitor movement is 10-20% of the nominal range. Finally, Figure 11A shows plasma ignition from an optimized preset position. The capacitor reaches the tuned position in less than 0.2 seconds with a small movement of 1-2% of the capacitor's nominal range.

[0059] Referring to Figures 8B, 9B, 10B, and 11B, repeated plasma processing is shown under the same conditions as shown in Figures 8A, 9A, 10A, and 11A. The RF power "Pfwd" is turned on for approximately 5 seconds, and then turned off for 3 seconds. Each time the RF is turned on, the matching circuit automatically adjusts the variable reactance or capacitor from its preset position and continues adjusting until a steady state is reached with the minimum reflected power "Prefl" and a fully ignited plasma. At the end of each plasma processing, in this case after 5 seconds, the RF power "Pfwd" is turned off, and the capacitor is returned to its preset position.

[0060] In the case of a vacuum variable capacitor, the capacitor's bellows compress and expand as the capacitor moves within its nominal range. The lifespan of a vacuum variable capacitor is strongly dependent on the amount of capacitor movement. Figure 12 shows a typical number of movement or adjustment cycles before bellows failure. For low movement amounts of less than 50% of the capacitor's nominal range, millions of movement or adjustment cycles can be achieved, but for high movement amounts, such as 80% of the nominal range, only a few hundred thousand cycles can be obtained before bellows failure.

[0061] Similarly, the lead screws and motors of vacuum variable capacitors or air capacitors degrade with increasing process cycle counts and rotational speeds per cycle. Therefore, mechanical operation per process cycle should be minimized.

[0062] In the examples in Figures 8A to 11B, it is clear that optimizing the movement of the capacitor within the matching circuit minimizes the amount of capacitor movement and the mechanical stress on its bellows. Simultaneously, the movement of the lead screw and motor is also minimized. In summary, optimizing the variable reactance or the preset position of the capacitor extends the overall lifespan of the matching circuit.

[0063] [Third example demonstrating the advantages of the present invention] Typically, the operating temperature of electrical, mechanical, or electromechanical components significantly impacts their lifespan before wear or failure occurs. However, in RF environments, monitoring component temperatures is often impossible or requires additional, expensive equipment due to RF wave interference. This is especially true for variable reactances within matching circuits. Internal components of vacuum capacitors, such as electrodes and mechanically stressed bellows and lead screws, operate at high currents and voltages, are in a vacuum, and move frequently, making them typically inaccessible with temperature sensing devices. Furthermore, the current and temperature flowing through reactance elements in matching circuits vary greatly depending on operating conditions, particularly the applied RF power (Pfwd) and plasma impedance. For example, high RF power levels (Pfwd) exceeding 1kW or low plasma resistance (e.g., less than 1Ω) can result in a 50A load. rms This can easily cause high RF currents exceeding a certain level, and therefore lead to high temperatures. At other power levels and impedances, the load on the components of the matching circuit can be significantly reduced.

[0064] By using functional relationships described by an RF circuit model, or by using lookup tables that associate activity information, RF frequency, and RF power, the impedance at the output of the matching circuit and the currents in various components of the matching circuit, including the variable reactance element, can be determined for each combination of variable reactance element positions. Using a second model of the RF matching circuit based on thermal modeling or a second lookup table, the temperature of each component of the RF matching circuit in a steady state can be determined. Further improvements to this method may take into account the temporal fluctuations in temperature due to changing impedance and current, and the temporal delays due to the slow heating and cooling of the thermal capacity of the components.

[0065] An example of applying this method is to first identify the usage profile and one or more process cycles used by a user of a plasma system, for example, through pattern recognition from activity data, and then determine the current and the temperature of the matching circuit components for each process cycle. Using the activity data and the temperature of the variable reactance element, the lifetime used per process cycle can be determined, and the remaining lifetime of the matching circuit can be calculated.

[0066] Instead of using ambient temperature, this method is far more accurate and allows for highly precise prediction of the expected lifespan of RF matching circuits based on actual usage profiles.

Claims

1. A method for operating an electronic system comprising a high-frequency (RF) matching circuit, wherein the RF matching circuit comprises a plurality of electronic components, and at least one of the electronic components is a variable reactance element. The method involves monitoring the activity information of at least one variable reactance element, and This includes determining the predicted lifespan from the aforementioned activity information.

2. The aforementioned method, To monitor at least one operating parameter of the electronic system, Determining the temperature of the electronic system from at least one of the aforementioned operating parameters, and The method according to claim 1, further comprising determining a predicted lifetime from the activity information and the determined temperature.

3. The aforementioned method, To monitor the RF frequency during operation of the aforementioned electronic system, and The method according to claim 1 or 2, further comprising determining a predicted lifetime from the activity information, the RF frequency during operation, and preferably the determined temperature.

4. The method according to any one of claims 1 to 3, wherein a warning signal is generated when the remaining predicted lifespan falls below a predetermined threshold.

5. The method according to any one of claims 1 to 4, wherein the predicted lifespan is displayed and / or transmitted to a remote server.

6. The method according to any one of claims 1 to 5, wherein the variable reactance element is one of a mechanically adjustable gas capacitor, a mechanically adjustable vacuum capacitor, or a mechanically adjustable inductor.

7. The method according to any one of claims 1 to 6, wherein the activity information is the mechanical adjustment of the variable reactance element.

8. The method according to any one of claims 1 to 7, wherein the at least one operating parameter includes the current of the electronic system, in particular the current in at least one of the plurality of electronic components.

9. Determining the temperature of the electronic system from at least one of the aforementioned operating parameters is: A lookup table is predetermined to provide a correspondence between at least one operating parameter and the temperature, and during operation, the temperature is retrieved for each of the operating parameters in the lookup table. A model of the variable reactance element and / or any other electronic component that provides a functional relationship between the at least one operating parameter and the temperature is predetermined, and the temperature is determined using the functional relationship during operation. A model of the electronic system including at least one variable reactance, further components, and parasitic inductance, capacitance and resistance is predetermined, a functional relationship is provided between the value of the variable reactance and the at least one operating parameter and the temperature, and the temperature is determined using the functional relationship during operation, and The method according to any one of claims 1 to 8, comprising at least one of: training a machine learning algorithm to determine the temperature from the at least one operating parameter; and determining the temperature using the trained machine learning algorithm during operation.

10. The method according to any one of claims 1 to 9, wherein the temperature includes one or more of the temperature of the variable reactance element, the temperature of any other electronic component, and the air temperature within the electronic system.

11. The method according to any one of claims 1 to 10, wherein the predicted lifetime includes the predicted number of remaining process cycles, and the predicted lifetime is calculated by the predicted number of remaining process cycles and the time between two process cycles.

12. The method according to claim 11, wherein, if the electronic system operates in two or more different process cycles, the predicted lifetime is determined by a combination of the predicted number of remaining process cycles for each different process cycle and the frequency of occurrence of each different process cycle.

13. The method according to claim 11 or 12, wherein the process cycle and the time between the two process cycles are determined by pattern recognition.

14. Determining the predicted lifetime means that A lookup table is predetermined to provide the connection between the activity information, preferably the temperature and / or the RF frequency, and the predicted lifetime; and during operation, the predicted lifetime for each of the activity information, preferably the temperature and / or the RF frequency, is retrieved from the lookup table. Preferably, a functional relationship between the activity information and the predicted lifetime is predetermined along with the temperature and / or the RF frequency, and the predicted lifetime is determined using the functional relationship during operation, and The method according to any one of claims 1 to 13, preferably comprising at least one of: training a machine learning algorithm to determine the predicted lifetime from the activity information together with the temperature and / or the RF frequency; and determining the predicted lifetime using the trained machine learning algorithm during operation.

15. An electronic system comprising an RF matching circuit, wherein the RF matching circuit comprises a plurality of electronic components, at least one of the electronic components being a variable reactance element, and the electronic system further comprises a control unit, the control unit configured to perform steps of the method according to any one of claims 1 to 14.

16. A plasma system comprising a plasma chamber and the electronic system according to claim 15 connected to the plasma chamber.

17. A non-transient, tangible, processor-readable storage medium encoded with processor-readable instructions that, when executed by a processor, perform steps according to any one of claims 1 to 14.

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