Plasma radio frequency power supply for coating based on double processors

Abstract

The invention discloses a secondary plasma radio-frequency power supply based on double processors, and the power supply comprises a DC power supply module which is used for converting 380V commercial power into DC and supplying the DC to a radio-frequency active power amplifier module for use; the radio frequency passive module is used for distributing or integrating radio frequency power; the radio frequency active power amplifier module is used for amplifying the radio frequency signal and outputting radio frequency voltage and current; the sampling module is used for coupling radio-frequency voltage and current, carrying out high-frequency ADC sampling and transmitting the radio-frequency voltage and current to the ZYNQ processor; the signal source module is used for outputting a radio frequency signal under the control of the ZYNQ processor; the dual-processor module comprises an STM32 processor and a ZYNQ processor; wherein the STM32 processor is used for monitoring the direct current power supply module and interacting with the upper computer; the ZYNQ processor is connected with the signal source module and the sampling module and is used for sampling digital signal processing and closed-loop power control. According to the invention, a ZYNQ + STM32 dual-processor structure is adopted, so that the dynamic response and stability of the power supply can be effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of plasma, and particularly to a plasma radio frequency power supply for coating based on a dual - processor. Background Art

[0002] Plasma Enhanced Chemical Vapor Deposition (PECVD) is a technology commonly used for preparing thin films. By applying a high - frequency electric field under low pressure to activate the gas, a plasma is generated to realize the process of coating on the target material. Plasma radio frequency power supplies have an objective layout in industry, but the quality of power supply use and working stability need to be tested. At the same time, the coating process has high requirements for film uniformity, film formation speed, and impurity content. For example, the film layer on a solar cell panel usually has a thickness of only nanometers and has very high requirements for uniformity. The radio frequency power supply needs to have a reliable arc - detection and arc - suppression function. At the same time, in order to ensure the normal progress of the coating process, the power supply needs a stable output power control mechanism, which puts forward high design requirements for the output of the radio frequency power supply.

[0003] Most of the existing plasma radio frequency power supplies have frequencies concentrated in the 13.56 MHz band, while the number of products at the 40.68 MHz level is very small, and the power level is low, unable to meet the occasions that require high - power plasma processing technology. Moreover, the existing radio frequency power supply system has a slow dynamic response speed, low sampling accuracy, poor system stability, and low efficiency. With the development of plasma applications, traditional radio frequency power supplies are increasingly unable to meet the growing performance requirements. Summary of the Invention

[0004] To solve at least one of the technical problems existing in the prior art to a certain extent, the purpose of the present invention is to provide a plasma radio frequency power supply for coating based on a dual - processor.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A plasma radio frequency power supply for coating based on a dual - processor includes the following steps:

[0007] A DC power supply module for converting 380V mains electricity into direct current for use by the radio frequency active power amplifier module;

[0008] A radio frequency passive module for distributing or integrating radio frequency power;

[0009] A radio frequency active power amplifier module for amplifying radio frequency signals and outputting radio frequency voltage and current;

[0010] A sampling module for coupling radio frequency voltage and current, performing high - frequency ADC sampling and transmitting it to the ZYNQ processor;

[0011] A signal source module for outputting radio frequency signals under the control of the ZYNQ processor;

[0012] Dual - processor module, including an STM32 processor and a ZYNQ processor; where the STM32 processor is used to monitor the DC power supply module and interact with the host computer; the ZYNQ processor is connected to the signal source module and the sampling module, and is used for sampling digital signal processing and closed - loop power control. At the same time, there is data communication between the two processors, namely the STM32 processor and the ZYNQ processor.

[0013] Furthermore, the RF passive module includes a power divider and a power combiner, and the RF active power amplifier module includes a pre - power amplifier and an RF active power amplifier;

[0014] The RF signal output by the signal source module passes through the pre - power amplifier, power divider, RF active power amplifier and power combiner in sequence to obtain the RF voltage and current.

[0015] Furthermore, the RF voltage and current are coupled to a band - pass filter through the voltage - current sensor of the sampling module, and after filtering out the high - frequency signal noise, they are sent to a high - speed ADC for sampling to obtain digital signals;

[0016] The digital signals are accessed to the PL end of the ZYNQ processor through LVDS differential signals, and digital signal processing is performed to obtain the amplitude and phase of the signals, and the output power situation of the power supply is calculated according to the amplitude and phase.

[0017] Furthermore, denote the incident voltage as U f , the reflected voltage as U r , the characteristic impedance of the transmission line as Z 0 , the angular frequency as ω, and the transmission speed of the electromagnetic wave in the conductor as V; if the length of the feeder tube from the output end of the RF active power amplifier to the sampling coils of the RF current and RF voltage is X meters, the sampling signals of the voltage amplitude sampling and current amplitude sampling are respectively:

[0018]

[0019] In the formula, U X is the voltage signal, and I X is the current signal;

[0020] Define the voltage - current conversion coefficients as k 1 k 2 , and the voltage sampling signal is:

[0021]

[0022] The voltage signal output by the current sampling is:

[0023]

[0024] Adjust the parameters so that k 1 = k 2 = k, then there is:

[0025]

[0026] Then the incident voltage amplitude U f is expressed as:

[0027]

[0028] The reflected voltage amplitude U r is expressed as:

[0029] The reflection coefficient is:

[0030]

[0031] In the formula, represents the incident voltage vector, represents the reflected voltage vector;

[0032] The voltage standing wave ratio is:

[0033] VSWR = (1 + |Γ|) / (1 - |Γ|)

[0034] The return loss is:

[0035] Return loss(dB) = -20log[(VSWR - 1) / (VSWR + 1)].

[0037] Furthermore, the arc suppression function of the power supply is completed by the cooperation of the sampling module and the ZYNQ processor. When the high-frequency ADC sampling collects abnormal rising current signals and falling voltage signals or other arcing phenomena, the ZYNQ processor will quickly cut off the output of the signal source module and then turn off the DC power supply.

[0038] Furthermore, the PID control algorithm is used to achieve closed-loop power control. The incremental PID is used and implemented in the PL part of the ZYNQ processor with Verilog language. The output of the PID controller acts on the output voltage amplitude of the signal source module to control the power output of the power supply, while the DC supply voltage remains unchanged during closed-loop control to more accurately let the signal source output directly control the output power.

[0039] Furthermore, the PL part of the ZYNQ processor uses the SPI communication protocol to control the output amplitude and frequency of the signal source module.

[0040] Further, the STM32 processor communicates with the temperature sensor through the I2C interface. The temperature sensor is responsible for collecting the real-time temperature of the transistors of the radio frequency active power amplifier and transmitting information to the STM32 processor through the I2C protocol.

[0041] The STM32 processor communicates with the host computer using the USART HMI protocol, responsible for receiving the power output parameters sent by the host computer and reporting the power operation parameters.

[0042] The STM32 processor communicates with the DC power supply module using the Modbus protocol, responsible for sending the power-on command of the power supply, monitoring the operation of the DC power supply in real time, and receiving the abnormal alarm information of the DC power supply, laying the foundation for the whole machine alarm logic.

[0043] Further, the STM32 processor communicates with the ZYNQ processor using the Modbus protocol, transmitting the host computer control information to be processed to the ZYNQ processor and receiving the real-time working conditions from the sampling module and the signal source module.

[0044] Further, the STM32 processor uses the FreeRTOS operating system to schedule multi-level tasks to improve the system operation speed and processing ability.

[0045] The beneficial effects of the present invention are as follows: The present invention adopts a dual-processor of ZYNQ + STM32. The ZYNQ processor is responsible for high-speed real-time radio frequency signal processing and completing the power closed-loop control and arc suppression protection functions. The STM32 processor is responsible for monitoring and controlling the DC power supply, realizing human-computer interaction with the host computer, and communicating with the ZYNQ for dual-processor communication, which can effectively improve the dynamic response and stability of the power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following introduces the relevant technical solution drawings in the embodiments of the present invention or the prior art. It should be understood that the drawings below only facilitate the clear expression of some embodiments of the technical solutions in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative efforts.

[0047] Figure 1 is a schematic diagram of the radio frequency vacuum plasma treatment process;

[0048] Figure 2 is a schematic diagram of the structure of a plasma radio frequency power supply for coating based on a dual-processor in an embodiment of the present invention;

[0049] Figure 3 is a schematic diagram of the working between the dual-processors in an embodiment of the present invention;

[0050] Figure 4 It is a schematic diagram of the working process of the plasma radio frequency power supply for coating in the embodiments of the present invention. Specific embodiments

[0051] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present invention and should not be construed as a limitation to the present invention. For the step numbers in the following embodiments, they are only set for the convenience of elaboration and explanation, and no limitation is imposed on the order between the steps. The execution order of each step in the embodiments can be adaptively adjusted according to the understanding of those skilled in the art.

[0052] In the description of the present invention, it should be understood that for the orientation description, such as the orientation or positional relationship indicated by up, down, front, back, left, right, etc., is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.

[0053] In the description of the present invention, the meaning of several is one or more, the meaning of multiple is more than two, greater than, less than, exceeding, etc. are understood as not including the present number, and above, below, within, etc. are understood as including the present number. If there is a description of first and second, it is only for the purpose of distinguishing technical features and should not be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence of the indicated technical features.

[0054] In the description of the present invention, unless otherwise clearly defined, words such as setting, installing, connecting, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0055] As Figure 1 shown, process gases are introduced into the plasma cavity. Specific different process gases are introduced according to the types of coating layers to be formed. The gases are ionized under the action of a radio frequency electric field in the cavity and a film layer is formed on the substrate. The residual gases are sucked in by the exhaust device and discharged.

[0056] Among them, the RF power supply provides a radio frequency electric field and power injection, which is loaded on the capacitively coupled parallel electrode plates; the heating device is responsible for raising the substrate temperature; the gas inlet and exhaust device is responsible for regulating the gas flow required for the film layer and controlling the air pressure in the cavity. After the exhaust system, there is a gas purifier to process the process residual gas, which is not shown in this figure. The gas is decomposed by the radio frequency electric field into free radicals, neutral molecules, positive ions, negative ions and electrons. Among them, the molecules, ions and free radicals undergo secondary reactions to generate the reaction substances required for the film layer. The neutral substances among them will diffuse to the substrate, and the positive ions bombard the growing thin film.

[0057] As Figure 2 shown, this embodiment provides a plasma radio frequency for coating based on a dual-processor, including a radio frequency passive module, a radio frequency active power amplifier module, a DC power supply module, a sampling module, a signal source module and a dual-processor module.

[0058] Among them, the radio frequency passive module includes a power divider and a power combiner. Different passive modules are respectively connected to the signal source or the radio frequency active power amplifier, and are used to distribute or integrate the radio frequency power. The radio frequency active power amplifier module includes a pre-power amplifier and a radio frequency active power amplifier, which are responsible for amplifying the small-power radio frequency signal source to a high-power radio frequency power output. Both the radio frequency passive module and the radio frequency active power amplifier module belong to the power circuit module. As an optional implementation manner, the radio frequency active power amplifier module is implemented by using a combination of a high-power class AB power amplifier and a high-power transistor.

[0059] The DC power supply module includes an AC / DC power supply, which is responsible for converting the 380V mains power into direct current for the radio frequency power amplifier to use.

[0060] The signal source module includes a signal source DDS, which outputs a radio frequency signal under the control of the ZYNQ processor and reaches the pre-power amplifier through the output filter in the signal source module.

[0061] The sampling module includes a signal sampling and conditioning circuit, which contains output voltage and current sensors and a high-frequency ADC chip, and is connected to the PL end of the ZYNQ processor.

[0062] The dual-processor module includes an STM32 processor and a ZYNQ processor. Among them, the STM32 processor is responsible for the control and monitoring of the AC / DC power supply and the interaction with the upper computer. The ZYNQ processor is connected to the signal source module and the sampling module, and is specifically used for sampling digital signal processing and closed-loop power control algorithms. At the same time, there is data communication between the two processors.

[0063] Among them, the sampling module, the signal source module and the dual-processor module constitute a sampling control and interaction module.

[0064] As Figure 3 shown, Figure 3It is the dual-processor part of the system. Among them, the radio frequency output voltage and current are coupled to the band-pass filter through the voltage and current sensors of the sampling module. After filtering out the high-frequency signal noise, they are sent to the high-speed ADC for sampling. The digital signal is accessed to the PL end of ZYNQ through LVDS differential signals. The step of differential-to-single-ended signal conversion is completed inside the PL. Further digital signal processing is carried out to obtain the amplitude and phase of the radio frequency signal. The output power situation of the power supply can be calculated from the amplitude and phase information of the output voltage and current respectively. Some formula derivations are as follows:

[0065] Denote the incident voltage as U f , and the reflected voltage as U r , the characteristic impedance of the transmission line as Z 0 , the angular frequency as w, and the transmission speed of the electromagnetic wave in the conductor as V. If the length of the feeder tube from the output end of the radio frequency amplifier to the radio frequency current and radio frequency voltage sampling coils is X meters, the sampling signals of the voltage amplitude sampling and current amplitude sampling are respectively:

[0066]

[0067] Among them, U X is the voltage signal, and I X is the current signal;

[0068] By measuring the voltage and current coupling degree of the VI sensor, the mathematical relationship between the sampling signal and the sampling signal can be obtained, and the hardware parameters of the sampling path can be designed. Define the voltage and current conversion coefficients as k 1 , k 2 .

[0069] The voltage sampling signal is:

[0070]

[0071] The voltage signal output by the current sampling is:

[0072]

[0073] Adjust the parameters so that k 1 = k 2 = k, then there is:

[0074]

[0075] Then the amplitude of the incident voltage U f can be expressed as:

[0076]

[0077] The amplitude of the reflected voltage U r can be expressed as:

[0078]

[0079] The reflection coefficient is:

[0080]

[0081] where represents the incident voltage vector, represents the reflected voltage vector;

[0082] The voltage standing wave ratio is:

[0083] VSWR = (1 + |Γ|) / (1 - |Γ|)

[0084] The return loss is:

[0085] Return loss(dB) = -20log[(VSWR - 1) / (VSWR + 1)]

[0086] In some embodiments, the arc suppression function of the power supply is completed by the cooperation of the sampling module and the ZYNQ processor. When the high-frequency sampling ADC detects an abnormally rising current signal and a falling voltage signal or other arcing phenomena, the ZYNQ processor will quickly cut off the output of the signal source DDS and then turn off the DC power supply.

[0087] As an implementation method, the closed-loop power control is realized by using the PID control algorithm. Here, the incremental PID is used and implemented in Verilog language on the PL side of the ZYNQ. The output of the PID controller acts on the output voltage amplitude of the signal source DDS to control the output power of the power supply, while the DC supply voltage remains unchanged during closed-loop control to more accurately let the signal source output directly control the output power.

[0088] In some embodiments, the PL side of the ZYNQ controls the output amplitude and frequency of the DDS by using the SPI communication protocol.

[0089] STM32 communicates with the temperature sensor through the I2C interface. The temperature sensor is responsible for collecting the real-time temperature of the transistors of the RF active power amplifier and transmitting the information to STM32 through the I2C protocol.

[0090] STM32 communicates with the host computer using the USART HMI protocol, responsible for receiving the power supply output parameters sent by the host computer such as power, frequency, etc., and reporting the power supply operation parameters such as the power supply output power, temperature conditions, etc.

[0091] STM32 communicates with the ZYNQ using the Modbus protocol, transmits the host computer control information to be processed to the ZYNQ, and receives the real-time working conditions from the sampling module and the signal source module.

[0092] The STM32 communicates with the AC / DC power supply using the Modbus protocol, responsible for sending the power-on instruction of the power supply, and real-time monitoring of the operation of the DC power supply, such as the real-time power, real-time voltage, and real-time current of each unit, and receiving the abnormal alarm information of the DC power supply, laying the foundation for the alarm logic of the whole machine.

[0093] The STM32 processor uses the FreeRTOS operating system to schedule multi-level tasks, improving the system operation speed and processing ability.

[0094] As Figure 4 shown, Figure 4 is the schematic diagram of the working process of the power supply described in this embodiment. After detecting the power-on signal, it judges whether the output conditions feedback by the PLC, such as cavity, gas and other information, and the power supply output conditions are met. If they are met, the upper computer preset output parameter enabling signal source DDS is loaded and the radio frequency signal is output, and the output amplitude is adjusted by the preset rising slope. During the normal working process, data sampling is carried out in real time (collecting the voltage and current at point X), and signal processing algorithms and closed-loop control are carried out, and internal data storage is also carried out at the same time; as an optional implementation method, the closed-loop power control adopts the PID control algorithm. Calculate whether the output power is consistent with the setting. If it is consistent, continue to output; if it is not consistent, the processor calculates and outputs an adjustment signal to adjust the amplitude of the signal source DDS for power adjustment; by continuously polling the sampling algorithm and the closed-loop control algorithm, it is ensured that the output power is always equal to the set power and continues to output until the stop signal arrives.

[0095] In summary, compared with the prior art, the present invention has the following advantages and beneficial effects:

[0096] (1) The power range of the power supply is improved. The combination of high-power class AB power amplifiers and high-power transistors is used, and multiple groups of parallel outputs can greatly improve the output power range of the radio frequency power supply. Combining a reasonable power splitter / combiner can effectively improve the rationality of the power supply layout. At the same time, a high-power AC / DC power supply is used for the whole machine power supply, and the maximum power supply power is greater than the maximum output power of the radio frequency power supply, which can ensure design redundancy and still achieve the maximum radio frequency power output under poor working conditions.

[0097] (2) The working frequency of the power supply is improved. The direct digital frequency synthesizer DDS can be used to output signals of any frequency, and can be combined with an automatic frequency modulation algorithm to complete small-range controllable frequency modulation of the output frequency, while the signal source using the combination of traditional crystal oscillators and logic gates cannot achieve a high working frequency.

[0098] (3)Improve the dynamic response and stability of the power supply. The power supply system of the present invention adopts a dual-processor of ZYNQ+STM32. ZYNQ is responsible for high-speed real-time radio frequency signal processing and completes the power closed-loop control and arc suppression protection functions. STM32 is responsible for monitoring and controlling the DC power supply, realizing human-computer interaction with the upper computer, and communicating with ZYNQ for dual-processor communication.

[0099] (4)Improve the efficiency of the power supply. The actual efficiency of high-power radio frequency power supplies is generally lower than 60%. The present invention improves the working efficiency by reasonably designing the power amplifier and setting a reasonable power link, and can reach an efficiency of 70% at the maximum power output.

[0100] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0101] The above embodiments are only for explaining the technical concept and characteristics of the present invention, and the purpose is to enable ordinary technicians in the art to understand the content of the present invention and implement it accordingly, and cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the essence of the content of the present invention should be covered by the protection scope of the present invention.

Claims

1. A plasma radio frequency power supply for coating based on a dual processor, characterized in that: The following steps are involved: The DC power supply module is used to convert 380V AC power into DC power for supplying to the RF active power amplifier module; RF passive modules, used to distribute or integrate RF power; RF active power amplifier module, used to amplify RF signals and output RF voltage and current; The sampling module is used to couple the RF voltage and current, perform high-frequency ADC sampling and transmit it to the ZYNQ processor; A signal source module, used to output a radio frequency signal under the control of the ZYNQ processor; The dual processor module includes an STM32 processor and a ZYNQ processor; the STM32 processor is used to monitor the DC power supply module and interact with the host computer; the ZYNQ processor is connected to the signal source module and the sampling module for sampling digital signal processing and closed-loop power control.

2. According to claim 1, a dual-processor based plasma RF power supply for film coating, characterized in that: The radio frequency passive module includes a power divider and a power combiner, and the radio frequency active power amplifier module includes a pre-power amplifier and a radio frequency active power amplifier; The RF signal output by the signal source module passes through the pre-power amplifier, power divider, RF active power amplifier and power synthesizer in sequence to obtain RF voltage and current.

3. The dual-processor based plasma RF power supply for film coating according to claim 1, characterized in that: The RF voltage and current are coupled to the bandpass filter through the voltage and current sensor of the sampling module, and are sent to the high-speed ADC for sampling after filtering out the high-frequency signal noise to obtain a digital signal; The digital signal is connected to the PL end of the ZYNQ processor through the LVDS differential signal, and the amplitude and phase of the signal are obtained by digital signal processing. The output power of the power supply is calculated based on the amplitude and phase.

4. The dual-processor based plasma RF power supply for film coating according to claim 3, characterized in that: The incident voltage is U f , the reflected voltage is U r , the characteristic impedance of the transmission line is Z0, the angular frequency is ω, and the transmission speed of the electromagnetic wave in the conductor is V; if the length of the feeder from the output end of the RF active power amplifier to the RF current and RF voltage sampling coils is X meters, the sampling signals of the voltage amplitude sampling and the current amplitude sampling are: Where U X is the voltage signal, I X is the current signal; The voltage and current conversion coefficients are defined as k1k2, and the voltage sampling signal is: The voltage signal output by current sampling is: Adjust the parameters so that k1=k2=k, then: Then the incident voltage amplitude U f It is expressed as: Reflected voltage amplitude U r It is expressed as: The reflection coefficient is: In the formula, represents the incident voltage vector, represents the reflected voltage vector; The standing wave ratio is: VSWR=(1+|Γ|) / (1-|Γ|) The return loss is: Return loss (dB)=-20log[(VSWR-1) / (VSWR+1)].

5. The dual-processor based plasma RF power supply for film coating according to claim 1, characterized in that: The arc suppression function of the power supply is achieved through the collaborative work of the sampling module and the ZYNQ processor. When the high-frequency ADC samples an abnormally rising current signal, a falling voltage signal or other arcing phenomena, the ZYNQ processor will quickly cut off the output of the signal source module and then shut down the DC power supply.

6. The dual-processor based plasma RF power supply for film coating according to claim 1, characterized in that: The PID control algorithm is used to achieve closed-loop power control. Incremental PID is used and implemented in the PL side of the ZYNQ processor using Verilog language. The PID controller output acts on the output voltage amplitude of the signal source module to control the power supply output power, while the DC supply voltage remains unchanged during closed-loop control, so that the signal source output can directly control the output power more accurately.

7. The dual-processor based plasma RF power supply for film coating according to claim 1, characterized in that: The PL end of the ZYNQ processor uses the SPI communication protocol to control the output amplitude and frequency of the signal source module.

8. The dual-processor based plasma RF power source for film coating according to claim 1, characterized in that: Said The STM32 processor uses the I2C interface to communicate with the temperature sensor. The temperature sensor is responsible for collecting the real-time temperature of the transistor of the RF active power amplifier and transmitting the information to the STM32 processor through the I2C protocol. The STM32 processor communicates with the host computer using the USART HMI protocol, is responsible for receiving the power output parameters sent by the host computer, and reporting the power operation parameters; The STM32 processor communicates with the DC power supply module using the Modbus protocol. It is responsible for sending power-on commands, monitoring the operation of the DC power supply in real time, and receiving abnormal DC power supply alarm information, paving the way for the alarm logic of the entire machine.

9. The dual-processor based plasma RF power source for film coating according to claim 1, characterized in that: The STM32 processor communicates with the ZYNQ processor using the Modbus protocol, transmits the host computer control information to be processed to the ZYNQ processor, and receives the real-time working status from the sampling module and the signal source module.

10. The dual-processor based plasma RF power source for film coating according to claim 1, characterized in that: The STM32 processor uses the FreeRTOS operating system to schedule multi-level tasks to improve the system operation speed and processing capability.

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