Split-type frequency mixing power division automatic matching system and method

Abstract

The invention discloses a split type frequency mixing power division automatic matching system and method. The split type frequency mixing power division automatic matching system comprises a frequency automatic matching unit, a frequency mixing power division unit and a bus communication module. The automatic frequency matching unit comprises at least two frequency matchers which are used for carrying out impedance adjustment on at least two paths of radio frequency power with different frequencies respectively; the frequency mixing power division unit is in signal connection with the automatic frequency matching unit and is used for receiving the radio frequency power subjected to impedance matching and distributing the received radio frequency power to a plurality of load cavities according to a preset proportion, and the power of each load cavity is independently controlled to be on and off; and the bus communication module is respectively connected with the automatic frequency matching unit, the frequency mixing power dividing unit and an external machine, and is used for realizing basic information interaction, working state reporting and control instruction transmission between each unit and the external machine. The frequency automatic matching unit is added, single-frequency power division is optimized into the frequency mixing power division unit, on the basis, the internal communication structure is optimized, the communication efficiency is improved, and the matching and power division time is shortened.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a split-type automatic matching system and method for power divider mixing. Background Technology

[0002] In fields such as semiconductor manufacturing, plasma processing, and radio frequency communication, precise matching and efficient allocation of radio frequency power are core technical requirements for ensuring equipment operational stability, process consistency, and energy utilization efficiency. With the widespread application of multi-band composite processes (such as high- and low-frequency coordinated control of plasma density and ion energy), traditional radio frequency power processing systems have gradually revealed many technical defects, making it difficult to meet the high-performance requirements under complex operating conditions.

[0003] Traditional RF power matching systems often employ a single-band centralized design, such as... Figure 1 As shown, impedance matching can only be performed on single-band RF signals. To adapt to multi-band signals, additional independent matching equipment is usually required, resulting in a bulky system with low integration. Furthermore, signal interference between different devices is difficult to suppress effectively, significantly reducing power transmission efficiency. At the same time, existing matching systems mostly use a single adjustment mode, lacking tiered adaptation for impedance deviations. This easily leads to adjustment overshoot or response lag, making it difficult to stably control the voltage standing wave ratio (VSWR) within a reasonable range. Consequently, this results in excessive reflected power and increased equipment losses.

[0004] In the power distribution stage, traditional mixer power dividers mostly use a fixed power distribution ratio structure, which cannot flexibly adjust the power distribution ratio according to actual load requirements, resulting in poor adaptability. Moreover, most devices lack independent on / off control and power backflow protection mechanisms. When a single load cavity stops working or malfunctions, it is easy for RF signal reflection and backflow to occur, damaging the front-end power devices. In addition, the signal acquisition and data processing of existing systems are mostly centralized architectures, with the acquisition module being far from the load cavity. This results in high acquisition delay and insufficient data accuracy for multi-band RF parameters, making it difficult to support the real-time and accurate power divider adjustment, further affecting the power distribution balance of multiple load cavities.

[0005] Meanwhile, the frequency matching unit and the mixing power divider unit in traditional systems have weak collaborative control capabilities. The two transmit data through decentralized communication links, which can easily lead to problems such as instruction delay and data loss, making it impossible to achieve dynamic collaborative optimization of impedance matching and power distribution. Furthermore, the system lacks a unified status monitoring and anomaly alarm mechanism. When faults such as abnormal temperature or power imbalance occur, it is difficult to respond quickly and take protective measures, which reduces the reliability and safety of system operation.

[0006] In summary, existing RF power matching and distribution systems suffer from technical problems such as low integration, poor multi-band adaptability, insufficient adjustment accuracy, lack of power distribution flexibility, weak collaborative control capabilities, and inadequate safety protection. There is an urgent need for an integrated solution that can achieve automatic impedance matching across multiple frequency bands, precise power distribution, efficient collaborative control, and reliable safety protection to meet the high-performance requirements of modern industrial production for RF power processing systems.

[0007] The disclosure of the above background information is only for the purpose of assisting in understanding the concept and technical solution of this application, and does not necessarily provide technical instruction. Summary of the Invention

[0008] The purpose of this invention is to provide a split-type automatic matching system and method for mixing and power division, which adds an automatic frequency matching unit and optimizes the single-frequency power division and mixing power division unit. Based on this, the internal communication structure is optimized to enhance communication efficiency and shorten matching and power division time.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A split-type automatic frequency matching system for mixing and power division includes an automatic frequency matching unit, a mixing and power division unit, and a bus communication module. The automatic frequency matching unit includes at least two frequency matching units, which are used to adjust the impedance of at least two different frequency radio frequency power signals respectively. The mixing power divider unit is signal-connected to the frequency automatic matching unit, and is used to receive the RF power after impedance matching, and to distribute the RF power to multiple load cavities according to a preset ratio, with the power of each load cavity being independently controlled to switch on and off. The bus communication module is connected to the automatic frequency matching unit, the mixing power divider unit, and the external machine respectively, and is used to realize basic information interaction, working status reporting, and control command transmission between the automatic frequency matching unit, the mixing power divider unit, and the external machine.

[0010] Furthermore, based on any or a combination of the aforementioned technical solutions, the frequency matching unit includes a coupling circuit module, a filtering circuit module, an AD sampling module, an FPGA computing module, a DSP control and communication module, and a motor drive module; The coupling circuit module is used for the coexistence and isolation of signals in different frequency bands; The filtering circuit module is used to filter and reduce noise for signals of different frequency bands to avoid cross-frequency interference. The AD sampling module is used to convert analog signals into digital signals; The FPGA computing module is used for real-time processing of digital signals, including filtering, power calculation, phase analysis, and fast communication. The DSP control and communication module is used to execute the closed-loop control algorithm and drive the motor to adjust the matching circuit. The motor drive module includes a stepper motor and an absolute encoder, used for precise control of the matching position.

[0011] Furthermore, based on any or a combination of the aforementioned technical solutions, the mixing power divider unit includes a VISensor acquisition module, a main control module, a motor drive module, a mixing power divider circuit module, and a split-type VISensor module. The VISensor acquisition module is used to aggregate multiple acquisition data and transmit them to the main control module through a high-speed parallel interface, and is connected to the split VISensor module through a high-speed digital interface to receive acquisition data. The main control module is used to generate power division adjustment commands after combining preset power ratio calculation and analysis. The main control module is connected to the VISensor acquisition module, the motor drive module, and the mixer power division circuit module to realize data reception and command issuance. The motor drive module is used to receive the adjustment command from the main control module, drive the precise adjustment of the power divider capacitors of each frequency band, and is connected to the mixer power divider circuit module through a capacitor adjustment link. The frequency mixer power divider circuit module is used to realize multi-band signal isolation, power distribution and output channel on / off control. It is connected to the main control module through control signals to receive on / off commands and feedback status. Its output terminal is connected to each of the load cavities. The split-type VISensor module is used to collect multi-band radio frequency parameters of each load cavity in real time, and transmit the collected data to the VISensor acquisition module through a high-speed digital interface.

[0012] Furthermore, following any or a combination of the aforementioned technical solutions, the automatic frequency matching unit includes a high-frequency matching unit and a low-frequency matching unit. The high-frequency matching unit is adapted to high-frequency radio frequency signals, and the low-frequency matching unit is adapted to low-frequency radio frequency signals. The high-frequency matching unit and the low-frequency matching unit achieve frequency band decoupling through a filter isolation design.

[0013] Furthermore, based on any one or a combination of the aforementioned technical solutions, the high-frequency matching device and the low-frequency matching device satisfy the following decoupling conditions: and

[0014] in, / Greater than or equal to 10, / Greater than or equal to 100 It is a high-frequency angular frequency. It is a low-frequency angular frequency. This is the peak value of the high-frequency voltage. This is a low-frequency voltage peak value. This refers to the instantaneous amplitude of the high-frequency voltage. This represents the instantaneous amplitude of the low-frequency voltage.

[0015] Furthermore, based on any or a combination of the aforementioned technical solutions, the mixing power divider circuit module includes a filter circuit, a power divider circuit, a relay, and an analog load; The output terminal of the filter circuit is connected to the input terminal of the power divider circuit; The output of the power divider circuit is divided into multiple branches, the number of which is the same as the number of load cavities, and each branch is connected in series with one of the relays. The output terminal of the relay is connected to the corresponding load cavity; The simulated load is connected in parallel with the relay.

[0016] Furthermore, in accordance with any or a combination of the aforementioned technical solutions, the mixing power divider circuit module is also equipped with an on / off control component, which is configured one-to-one with each load cavity to control the on / off of the power output channel of the corresponding load cavity. The on / off control component is connected to the main control module via control signals, receives on / off commands issued by the main control module, and provides feedback on its working status.

[0017] Furthermore, following any one or a combination of the aforementioned technical solutions, the frequency matching device further includes a matching circuit. Each matching circuit of the frequency matching device includes a tuning capacitor and a load capacitor. The tuning capacitor is used to adjust the imaginary part of the impedance, and the load capacitor is used to adjust the real part of the impedance.

[0018] Furthermore, based on any or a combination of the aforementioned technical solutions, the automatic frequency matching unit has a built-in input sensor for real-time detection of the voltage, current, and phase angle of the radio frequency signals in each frequency band, and for calculating the real and imaginary parts of the impedance of the radio frequency signals in each frequency band, as well as the forward power, reverse power, and voltage standing wave ratio of the radio frequency signals in each frequency band. The voltage standing wave ratio is compared with a preset threshold, and corresponding adjustment steps are performed based on the comparison result.

[0019] According to another aspect of the present invention, the present invention provides a method for automatic matching of a split-type mixer power divider, applied to the split-type mixer power divider automatic matching system as described above, comprising the following steps: When the device is powered on, the automatic frequency matching unit and the mixing power divider unit perform self-tests to confirm hardware connections, module status and user-selected working modes, and report basic device information to the external machine through the bus communication module. The external machine sends impedance matching parameters to the frequency automatic matching unit through the bus communication module, and sends preset power distribution ratio and load cavity on / off control commands to the mixing power division unit. Each frequency automatic matching unit and the mixing power division unit receives the corresponding control commands based on an independent address identifier. When the radio frequency power supply is started, at least two frequency matching units of the automatic frequency matching unit are respectively connected to at least two radio frequency power sources of different frequencies. The built-in sensors detect the voltage, current and phase angle of the radio frequency signals of each frequency band in real time, calculate the real part, imaginary part, forward power, reverse power and voltage standing wave ratio of the impedance, and independently adjust the matching circuit parameters of each frequency band to achieve targeted impedance adjustment and reduce reflected power. The mixing power divider receives the radio frequency power after impedance matching by the frequency automatic matching unit, and distributes the radio frequency power to multiple load cavities according to a preset ratio.

[0020] The beneficial effects of the technical solution provided by this invention are as follows: a. Strong multi-frequency adaptability and low interference, precise and efficient power allocation: The dual-frequency automatic matching unit (high-frequency + low-frequency matching unit) enables independent impedance adjustment of multi-band RF signals, meeting the requirements of multi-frequency composite processes. Furthermore, the filtering isolation design and specific decoupling conditions reduce mutual interference between high and low frequency signals. The mixing power divider unit relies on a split VISensor module and high-speed interface transmission. Combined with the "coarse adjustment + fine adjustment" algorithm, it can accurately allocate power to multiple load cavities according to a preset ratio. At the same time, the relays at each output end work with the analog load to avoid power backflow and improve energy utilization efficiency. b. Fast response speed and stable and reliable operation, convenient maintenance and expansion: The matching and power division process are optimized in tandem, which can quickly adapt to the dynamic changes of plasma conditions; the use of absolute encoder and high-precision stepper motor, combined with closed-loop control algorithm, avoids adjustment overshoot and error accumulation, and significantly reduces reflected power; c. The system features a split-modular design, with the matching unit and power distribution unit maintained independently. It also supports precise interaction between multiple devices via a bus communication module and has the ability to detect and protect against anomalies such as those related to fans, temperature, and power balance. This facilitates system expansion and upgrades while improving equipment operation safety and process repeatability. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of an existing automatic power distribution matching system; Figure 2 A schematic diagram of a split-type automatic matching system for mixer power divider provided as an exemplary embodiment of the present invention; Figure 3 A schematic diagram of a matching unit module provided for an exemplary embodiment of the present invention; Figure 4 A schematic diagram of a low-frequency matching circuit provided for an exemplary embodiment of the present invention; Figure 5 A schematic diagram of a high-frequency matching circuit provided for an exemplary embodiment of the present invention; Figure 6 A schematic diagram of a mixing power divider unit provided as an exemplary embodiment of the present invention; Figure 7 A schematic diagram of a mixer power divider circuit is provided for an exemplary embodiment of the present invention. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0024] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, apparatus, product, or device that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or devices.

[0025] In one embodiment of the present invention, such as Figure 2 As shown, a split-type automatic matching system for mixer power divider is provided, including: an automatic frequency matching unit, a mixer power divider unit, and a bus communication module; the automatic frequency matching unit includes at least two frequency matchers, used to adjust the impedance of at least two different frequency RF power signals respectively, reducing reflected power and reducing mutual interference between high and low frequency signals; the mixer power divider unit is signal-connected to the automatic frequency matching unit, used to receive the impedance-matched RF power, and distribute it to multiple load cavities according to a preset ratio, with the power of each load cavity independently controlled on / off; the bus communication module is connected to the automatic frequency matching unit, the mixer power divider unit, and an external machine, respectively, used to realize basic information exchange, working status reporting, and control command transmission among the three, and to distinguish different devices by address to achieve data sharing.

[0026] This split-type automatic matching system for mixing and power division adopts a split architecture that combines at least two automatic frequency matching units with an optimized mixing and power division unit. With the help of a bus communication module, it achieves efficient collaborative control. It can reduce mutual interference between high and low frequency signals through coupling circuits, filtering circuit modules and specific decoupling conditions, and realize independent impedance adjustment and precise allocation of multi-band RF power to meet the requirements of multi-frequency composite processes.

[0027] In one embodiment of the present invention, the frequency automatic matching unit is as follows: Figure 3 As shown, each frequency matching unit includes a coupling circuit module, a filtering circuit module, an AD sampling module, an FPGA computing module, a DSP control and communication module, and a motor drive module. The coupling circuit module enables the coexistence and isolation of signals in different frequency bands. The filtering circuit module filters and reduces noise for signals in the corresponding frequency band to avoid cross-band interference. The AD sampling module converts analog signals into digital signals. The FPGA computing module processes digital signals in real time and calculates parameters such as power, phase angle, and impedance. The DSP control and communication module executes a closed-loop control algorithm to drive the motor and adjust the matching circuit. The motor drive module includes a stepper motor and an absolute encoder for precise control of the matching capacitor position.

[0028] In one embodiment of the present invention, such as Figure 6As shown, the mixing power divider unit includes a VISensor acquisition module, a main control module, a motor drive module, a mixing power divider circuit module, and a split-type VISensor module. The VISensor acquisition module aggregates multi-channel acquired data and transmits it to the main control module via a high-speed parallel interface. It is also connected to the split-type VISensor module via a high-speed digital interface to receive acquired data. The main control module generates power divider adjustment commands after combining preset power ratio calculations and analyses. It is connected to the VISensor acquisition module, the motor drive module, and the mixing power divider circuit module to achieve data reception and command issuance. The motor drive module receives the adjustment commands from the main control module and drives the actuators to precisely adjust each... A frequency band power divider capacitor is included, and it is connected to the mixer power divider circuit module via a capacitor adjustment link. The mixer power divider circuit module is used to realize multi-band signal isolation, power distribution, and output channel on / off control. It is connected to the main control module through a control signal to receive on / off commands and feedback status. Its output terminal is connected to each of the load cavities. The mixer power divider circuit module includes a filter circuit, a power divider circuit, a relay, and an analog load. The output terminal of the filter circuit is connected to the input terminal of the power divider circuit. The output terminal of the power divider circuit is divided into multiple branches, the number of which is consistent with the number of load cavities. Each branch is connected in series with one of the relays. The output terminal of the relay is connected to the corresponding load cavity. The analog load is connected in parallel with the relay. The split-type VISensor module is used to collect multi-band RF parameters of each load cavity in real time and transmit the collected data to the VISensor acquisition module through a high-speed digital interface.

[0029] The mixing power divider circuit module is also equipped with an on / off control component. The on / off control component is set one-to-one with each load cavity and is used to control the on / off of the power output channel of the corresponding load cavity. The on / off control component is connected to the main control module through a control signal, receives the on / off command issued by the main control module and feeds back its own working status.

[0030] The mixing power divider unit uses an external VISensor sensor and a high-speed digital interface to aggregate various RF signals to the sensor acquisition module, with an update rate of 2.5ms-10ms. Within 10ms, the sensor acquisition module acquires the LoadPower of several outputs, packages and aggregates the data using a dedicated internal simplified protocol, and sends it to the power divider control module via a parallel high-speed interface. The power divider module precisely controls the high and low frequency power divider capacitors by adjusting the combination of a stepper motor and an absolute encoder based on the actual power of each channel and the customer-set power. By setting a high- and low-frequency selective filtering network before the automatic power divider and employing a dual-frequency combining structure at the output, independent adjustment and joint output of high-frequency and low-frequency power are achieved, thereby improving the dual-frequency energy coupling efficiency, avoiding signal backflow and crosstalk, and significantly improving the stability and repeatability of the plasma process. The main function of adding relays at each output is to select, isolate, and protect the output channel, ensuring safe, controllable, and switchable power transmission. When the relay is disconnected, the RF signal will switch to the analog load to provide a stable equivalent load in the channel-off state, thereby avoiding RF power backfeedback and reflection, ensuring the safety of the power amplifier, the stability of the matching network, and the continuity of the plasma process.

[0031] In one embodiment of the present invention, the matching circuit of each frequency matcher includes a tuning capacitor and a load capacitor, wherein the tuning capacitor is used to adjust the imaginary part of the impedance, and the load capacitor is used to adjust the real part of the impedance; the low-frequency matching circuit is as follows: Figure 4 As shown, the high-frequency matching circuit is as follows: Figure 5 As shown.

[0032] In one embodiment of the present invention, the split-type automatic mixing power divider matching system (taking dual-frequency automatic matching as an example) is further described in detail: The core of the split-type automatic matching system for mixer-power divider in this embodiment consists of three main parts: a dual-frequency automatic matching unit, a mixer-power divider unit, and a bus communication module. Each unit adopts a modular and separate design, and coordinated control is achieved through a 485 bus communication module. The overall architecture is as follows: Figure 2 As shown in the diagram. The dual-frequency automatic matching unit is responsible for the independent impedance adjustment of two different frequency RF signals. The mixer power divider unit achieves precise allocation and on / off control of the matched RF power. The bus communication module establishes a bidirectional data interaction channel between each unit and external equipment, ensuring the overall efficient operation of the system.

[0033] The dual-frequency automatic matching unit consists of a high-frequency (HF) matching unit and a low-frequency (LF) matching unit. The HF matching unit is adapted to high-frequency radio frequency signals (e.g., HF 13.56MHz, HF above 4MHz is sufficient), and the LF matching unit is adapted to low-frequency radio frequency signals (e.g., LF 400kHz). Their structures are basically the same, differing only in the internal matching circuit parameters. Specifically, it includes a coupling circuit module, a filtering circuit module, an AD sampling module, an FPGA processing module, a DSP control and communication module, and a motor drive module. The module block diagram is shown below. Figure 4 As shown.

[0034] Coupled circuit module: It adopts an LC resonant structure and utilizes the selectivity of inductors and capacitors for different frequencies to allow high-frequency signals and low-frequency signals to coexist on the same electrode and be isolated from each other, thus ensuring independent control of plasma density and ion energy.

[0035] Filtering circuit module: HF and LF matched circuits are configured with bandpass filters to achieve channel isolation of dual-frequency signals and avoid cross-frequency interference.

[0036] AD sampling module: It adopts a high-precision ADC chip with a sampling rate of 1MHz, which converts the filtered high and low frequency analog signals into digital signals for processing by the FPGA computing module.

[0037] FPGA computing module: Supports high-speed parallel processing, performs real-time filtering, power calculation, and phase analysis on digital signals, and can accurately output parameters such as the real part of impedance, imaginary part, forward power, reverse power, and voltage standing wave ratio (VSWR).

[0038] DSP control and communication module: Supports UPP communication protocol, quickly executes closed-loop control algorithm, and realizes precise control of motor position, speed and acceleration.

[0039] Motor drive module: Equipped with a high-precision stepper motor and a 16-bit absolute encoder with a resolution of 65,536 steps / revolution. It does not require zeroing upon power-up and can provide real-time feedback on the absolute position of the capacitor rotation angle.

[0040] Matching circuits: Both HF and LF matching circuits include a tuning capacitor and a load capacitor. The tuning capacitor has a capacitance range of 10-100pF and represents the imaginary part of the main impedance; the load capacitor has a capacitance range of 20-200pF and represents the real part of the main impedance. The circuit designs are as follows: Figure 5 , Figure 6 As shown.

[0041] The high-frequency matching unit is adapted to high-frequency radio frequency signals, and the low-frequency matching unit is adapted to low-frequency radio frequency signals. The high-frequency matching unit and the low-frequency matching unit achieve frequency band decoupling through a filter isolation design.

[0042] The high-frequency matching unit and the low-frequency matching unit satisfy the following decoupling conditions: and

[0043] in, It is a high-frequency angular frequency. It is a low-frequency angular frequency. This is the peak value of the high-frequency voltage. This is a low-frequency voltage peak value. This refers to the instantaneous amplitude of the high-frequency voltage. This represents the instantaneous amplitude of the low-frequency voltage.

[0044] It is worth noting that ">>" indicates 100 times or more, that is... / A value greater than or equal to 10 means that the high-frequency angular frequency is at least 10 times higher than the low-frequency angular frequency. / Greater than or equal to 100, meaning the instantaneous voltage amplitudes differ by at least 100 times.

[0045] The mixing power divider unit receives the RF power output from the dual-band automatic matching unit and distributes it to three load cavities according to a preset ratio. Specifically, it includes a VISensor acquisition module, a main control module, a motor drive module, a mixing power divider circuit module, and a separate VISensor module. Figure 2-3 As shown in Figures 7 and 8.

[0046] Split-type VISensor module: There are 3 modules in total, each corresponding to 3 load cavities. Each module has built-in voltage and current sensors and phase detection circuits, which can measure multi-frequency RF parameters in real time. The data update rate is 5ms (design range is within 2.5ms-10ms). The acquired data is transmitted to the VISensor acquisition module through a high-speed digital interface (SPI protocol, communication rate 50Mbps).

[0047] VISensor acquisition module: It uses an FPGA chip to aggregate multiple data channels. It packages the power data of the three cavities through a dedicated internal simplified protocol with a processing delay of ≤2ms, and then transmits it to the main control module through a high-speed parallel interface (LVDS protocol).

[0048] Main control module: Selected STM32H7 series MCU with a main frequency of 480MHz, it has high-speed data processing capabilities, can monitor RF power, impedance and cavity status in real time, generate division and modulation commands through automatic power division algorithm, and has abnormal detection and protection functions for fan status, temperature status and power balance status.

[0049] Motor drive module: Configured with 6 sets of stepper motors + absolute encoders (3 sets each for HF and LF bands), with parameters consistent with the dual-frequency automatic matching unit, corresponding to the high and low frequency power divider capacitor adjustment of the 3 load chambers respectively.

[0050] Mixer power divider module: Includes a built-in high / low frequency selective filter network, power divider circuit, 3 relays, and 3 analog loads (50Ω impedance). Circuit block diagram is shown below. Figure 7 As shown. The relay is an electromagnetic relay with a response time of ≤10ms. When the relay is disconnected, the radio frequency signal of the corresponding cavity is switched to the analog load to avoid power backflow.

[0051] The bus communication module uses a 485 bus interface with a communication rate of 115200bps. It distinguishes between the dual-frequency automatic matching unit (HF matcher address 0x01, LF matcher address 0x02) and the mixing power divider unit (address 0x03) by address, realizing basic information exchange, working status reporting and control command transmission between external equipment and each unit. The data transmission error rate is relatively small.

[0052] This embodiment is only used to explain the present invention and is not intended to limit the scope of protection of the present invention.

[0053] The split-type automatic power divider matching system of this embodiment has achieved the following technical effects after actual testing: The dual-frequency signal isolation is ≥45dB, significantly reducing mutual interference between high and low frequency signals. The reflected power of the HF band is ≤5W, and the reflected power of the LF band is ≤3W, improving energy utilization efficiency. The power distribution error of the three load cavities is reduced, meeting the preset ratio requirements, and the uniformity of the etching process is improved. When the relay of a certain cavity is disconnected, the RF signal is successfully switched to the analog load, the reflected power does not increase significantly, and no power backflow phenomenon occurs.

[0054] In summary, this embodiment achieves efficient matching, precise allocation, and stable transmission of dual-frequency RF power through reasonable module selection, parameter settings, and process design. It effectively solves the technical defects of traditional single-frequency systems and is suitable for multi-frequency RF process scenarios such as advanced semiconductor etching and thin film deposition.

[0055] In one embodiment of the present invention, a method for automatic matching of a split-type mixer power divider is provided, applied to the split-type mixer power divider automatic matching system described above, comprising the following steps: After the equipment is powered on, the frequency matching unit and the mixing power divider unit perform self-tests to confirm the hardware connection, module status and user-selected working mode. The working mode is manual or automatic. The equipment basic information is reported to the external machine through the bus communication module. (2) The external machine sends impedance matching parameters to the frequency automatic matching unit through the bus communication module, and sends preset power distribution ratio and load cavity on / off control commands to the mixing power division unit. Each unit receives the corresponding control commands based on its independent address identifier. (3) Start the RF power supply. At least two frequency matching units of the frequency automatic matching unit are respectively connected to two different RF power signals. The built-in sensors detect the voltage, current and phase angle of the RF signal in each frequency band in real time, calculate the real part, imaginary part, forward power, reverse power and voltage standing wave ratio of the impedance, and independently adjust the matching circuit parameters of each frequency band to achieve targeted impedance adjustment and reduce reflected power. (4) The mixing power divider receives the RF power after impedance matching by the frequency automatic matching unit, and collects the multi-band RF parameters of each load cavity in real time through the split VISensor module. After being collected by the VISensor acquisition module, the parameters are transmitted to the main control module. (5) The main control module performs calculation and analysis based on the preset power distribution ratio and the real-time collected power data, generates power distribution adjustment instructions, drives the motor drive module to precisely adjust the power distribution capacitors of each frequency band, distributes the radio frequency power to multiple load cavities according to the preset ratio, and controls the power on / off of each load cavity independently through relays according to the external machine instructions and the working status of the cavity. (6) During the impedance matching and power distribution process, the frequency automatic matching unit and the mixing power distribution unit report their working status to the external machine in real time through the bus communication module. The working status includes adjustment progress, current power parameters, impedance matching effect, cavity on / off status, etc. (7) When the voltage standing wave ratio reaches the preset stable threshold and the power of each load cavity meets the preset ratio requirement, the active adjustment is stopped. If the load condition changes, causing the voltage standing wave ratio to exceed the preset range or the power distribution deviation to exceed the threshold, the corresponding adjustment process is restarted to ensure stable operation of the system.

[0056] For example, the automatic matching workflow includes a matching process and a power distribution process, which are performed simultaneously, as follows: (a) Matching process After the equipment is powered on, the dual-frequency automatic matching unit performs a self-test, which detects the status of the motor encoder, fan, temperature and circuit connection. After the self-test is passed, the basic equipment information is reported to the external machine through the bus communication module. Users can select the automatic working mode through an external machine and set the VSWR threshold (e.g., minimum 1.2, maximum 1.5) to ensure that the DEADBAND is between 1.03 and 1.05 or the reflected power is less than 1W. With the RF power turned on, the HF matching circuit is connected to a 13.56MHz RF signal (input power 300W), and the LF matching circuit is connected to a 400kHz RF signal (input power 200W). The built-in InPutSensor of the dual-frequency automatic matching unit detects the input voltage, current and phase angle in real time, and calculates the real part, imaginary part, forward power, reverse power and VSWR parameters through the FPGA computing module. When the RF power is detected to reach the turn-on threshold (HF≥50W, LF≥30W), impedance matching adjustment is initiated: the Tune capacitor mainly adjusts the imaginary part of the impedance, and the Load capacitor mainly adjusts the real part of the impedance, adopting a "coarse adjustment + fine adjustment" strategy—when the deviation between the actual impedance and the target impedance (50Ω) is greater than 5%, the stepper motor performs coarse adjustment with a large step of 100 steps / time; when the deviation is less than 5%, fine adjustment is performed with a small step of 10 steps / time. When VSWR reaches the preset minimum value of 1.2, the adjustment stops; if VSWR is greater than the preset maximum value of 1.5, the adjustment restarts to avoid the device from continuously adjusting due to small power fluctuations. During the adjustment process, the matching status (adjustment in progress / adjustment complete, current VSWR value, capacitor position, etc.) is transmitted to the external machine in real time via the bus.

[0057] (II) Power Division Process After the equipment is powered on, the mixing power division unit performs a self-test synchronously, detecting the status of sensors, relays and simulated load connections. After passing the self-test, it reports the basic equipment information to the external machine. Users can set the power distribution ratio of the three load chambers through an external device (e.g., HF band: 1:1:1, LF band: 2:1:1). The VISensor acquisition module acquires high and low frequency power data from three cavities in real time through a split-type VISensor module, and then transmits the data to the main control module after aggregation. When the main control module detects that the total power of the back-end HF is ≥250W and the total power of the LF is ≥150W, the power sharing mode is activated. The main control module generates a power distribution command based on the difference between the preset power ratio and the actual collected power. This command drives the motor to adjust the high and low frequency power distribution capacitors in each cavity. The module employs a "coarse adjustment + fine adjustment" strategy: when the absolute value of the difference between the actual power and the preset power is greater than 5%, coarse adjustment is performed; when the absolute value of the difference is less than 2%, the power adjustment for that channel is stopped. When the high and low frequency power of the three cavities all meet the preset ratio requirements, the power division is stopped; if the absolute value of the power difference of a certain channel is greater than 5%, the adjustment of that channel is restarted. During the adjustment process, the power distribution status (adjustment in progress / adjustment complete, current power values ​​of each cavity, etc.) is transmitted to the external equipment in real time via the bus.

[0058] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0059] The above description is only a specific embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A split type mixed power-division automatic matching system, characterized in that, The application relates to a frequency automatic matching unit, a mixed frequency power division unit and a bus communication module. The frequency automatic matching unit comprises at least two frequency matchers for respectively adjusting the impedance of at least two paths of radio frequency power with different frequencies. The mixed frequency power division unit is connected with the frequency automatic matching unit and is used for receiving the radio frequency power after impedance matching and receiving the radio frequency power which is distributed to multiple load cavities according to a preset ratio. The bus communication module is connected with the frequency automatic matching unit, the mixed frequency power division unit and an external machine and is used for realizing basic information interaction, working state reporting and control instruction transmission among the frequency automatic matching unit, the mixed frequency power division unit and the external machine. The frequency matcher comprises a coupling circuit module, a filter circuit module, an AD sampling module, an FPGA operation module, a DSP control and communication module and a motor driving module.

2. The split-mixer power-division automatic matching system of claim 1, wherein, The coupling circuit module is used for coexistence and isolation of signals of different frequency bands. The filter circuit module is used for filtering and noise reduction of signals of different frequency bands to avoid cross-frequency band interference. The AD sampling module is used for converting analog signals into digital signals. The FPGA operation module is used for real-time processing of digital signals, including filtering, power calculation, phase analysis and fast communication. The DSP control and communication module is used for executing a closed-loop control algorithm to drive a motor to adjust a matching circuit. The motor driving module comprises a stepping motor and an absolute value encoder and is used for accurately controlling a matching position. The mixed frequency power division unit comprises a VISensor acquisition module, a master control module, a motor driving module, a mixed frequency power division circuit module and a split VISensor module.

3. The split-mixer power-division automatic matching system according to claim 1 or 2, wherein, The VISensor acquisition module is used for collecting multiple acquisition data and transmitting the data to the master control module through a high-speed parallel interface and is connected with the split VISensor module through a high-speed digital interface to receive acquisition data. The master control module is used for generating a power distribution adjustment instruction after operation and analysis according to a preset power ratio, is connected with the VISensor acquisition module, the motor driving module and the mixed frequency power division circuit module to realize data receiving and instruction issuing. The motor driving module is used for receiving the adjustment instruction of the master control module, driving accurate adjustment of frequency division capacitors and is connected with the mixed frequency power division circuit module through a capacitor adjustment link. The mixed frequency power division circuit module is used for realizing multi-frequency signal isolation, power distribution and output channel on-off control, is connected with the master control module through a control signal to receive on-off instructions and feed back states, and is connected with the load cavities. The split VISensor module is used for real-time acquisition of multi-frequency radio frequency parameters of the load cavities, transmits acquisition data to the VISensor acquisition module through a high-speed digital interface. ​ 4. The split-block frequency-mixing power-division automatic matching system according to any one of claims 1-3, characterized in that, The frequency automatic matching unit comprises a high-frequency matching device and a low-frequency matching device, the high-frequency matching device is adapted to high-frequency radio frequency signals, the low-frequency matching device is adapted to low-frequency radio frequency signals, and the high-frequency matching device and the low-frequency matching device are designed to realize frequency band decoupling through filter isolation.

5. The split-block frequency-mixing power-division automatic matching system of claim 4, wherein, The high-frequency matching device and the low-frequency matching device satisfy the following decoupling condition: and wherein / 10, / 100, is the high frequency corner frequency, is the low frequency corner frequency, is the high frequency voltage peak value, is the low frequency voltage peak value, is the high frequency voltage instantaneous amplitude, is the low frequency voltage instantaneous amplitude.

6. The split-block frequency-mixing power-division automatic matching system of claim 3, wherein, The frequency mixing power dividing circuit module comprises a filter circuit, a power dividing circuit, a relay and an analog load. An output end of the filter circuit is connected to an input end of the power dividing circuit. An output end of the power dividing circuit is divided into a plurality of branches, the number of the branches is consistent with the number of the load cavities, and one relay is connected in series to each branch. An output end of the relay is connected to a corresponding load cavity. The analog load is connected in parallel to the relay.

7. The split-mixer power-division automatic matching system of claim 3 or 4, wherein, The frequency mixing power dividing circuit module is further provided with on-off control components, the on-off control components are arranged one-to-one corresponding to each load cavity, and are used for controlling the on-off of a power output channel of the corresponding load cavity. The on-off control components are connected to the main control module through a control signal, receive an on-off instruction issued by the main control module and feed back a working state.

8. The split-block frequency-mixing power-division automatic matching system of claim 1, wherein, The frequency matching device further comprises a matching circuit, the matching circuit of each frequency matching device comprises a tuning capacitor and a load capacitor, the tuning capacitor is used for adjusting an imaginary part of impedance, and the load capacitor is used for adjusting a real part of impedance.

9. The split-block frequency-mixing power-division automatic matching system of claim 7, wherein, The frequency automatic matching unit is provided with an input sensor, which is used for detecting voltages, currents and phase angles of radio frequency signals of each frequency band in real time, and calculating real parts and imaginary parts of impedances of the radio frequency signals of each frequency band, and forward powers, reverse powers and voltage standing wave ratios of the radio frequency signals of each frequency band. The voltage standing wave ratio is compared with a preset threshold value, and corresponding adjustment steps are performed according to a comparison result.

10. A split-mixer power-division automatic matching method, applied to the split-mixer power-division automatic matching system of any one of claims 1-9, characterized in that, The method comprises the following steps: When the device is powered on, the frequency automatic matching unit and the frequency mixing power dividing unit perform self-checking, confirm hardware connection, module state and a working mode selected by a user, and report device basic information to an external machine through the bus communication module; The external machine issues impedance matching related parameters to the frequency automatic matching unit and issues a preset power distribution ratio and load cavity on-off control instructions to the frequency mixing power dividing unit through the bus communication module, and each frequency automatic matching unit and the frequency mixing power dividing unit receives corresponding control instructions based on independent address identification; Radio frequency power supply is started, at least two frequency matching devices of the frequency automatic matching unit respectively interface at least two radio frequency powers of different frequencies, real-time detection of voltages, currents and phase angles of radio frequency signals of each frequency band is performed through the built-in sensor, calculation of real parts and imaginary parts of impedances, forward powers, reverse powers and voltage standing wave ratios is performed, independent adjustment of parameters of each frequency band matching circuit is performed, targeted impedance adjustment is realized, and reflected power is reduced; The frequency mixing power dividing unit receives radio frequency powers matched by the frequency automatic matching unit, and distributes the radio frequency powers to a plurality of load cavities according to the preset ratio.

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