A fast automatic impedance matching system and matching method

Abstract

The application relates to a rapid automatic impedance matching system and a matching method, and belongs to the technical field of semiconductor equipment manufacturing. The rapid automatic impedance matching system comprises an adjustable frequency radio frequency power supply module, a radio frequency cable module, a matcher module and a chamber load module, the adjustable frequency radio frequency power supply is integrated with a VI sensor, and is used for measuring output voltage |V|, current |I| and phase difference phi in real time; the matcher only contains a single adjustable capacitor element C1, and the capacitance value is adjusted through motor driving. The matching method comprises the following steps: calculating the impedance Z of the output end of the radio frequency power supply based on VI sensor data s , deducing the input admittance of the matcher in combination with cable characteristic parameters, solving the target frequency value f1 and the target capacitance value C1 by analyzing the load resistance R and the inductance L, and realizing single-step matching control. The application improves the matching speed, simplifies the hardware, reduces the cost and enhances the stability.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor equipment manufacturing technology, specifically relating to a fast automatic impedance matching system and matching method. Background Technology

[0002] Inductively Coupled Plasma (ICP) devices are key equipment in integrated circuit manufacturing processes, widely used in core processes such as etching and thin film deposition. They efficiently transfer energy to the load via a radio frequency (RF) system to excite and maintain the plasma, directly impacting chip manufacturing precision and yield. The RF system of an ICP device mainly consists of an RF generator (RFG), an RF cable, an impedance matcher, and an RF coil. Each component has a clear function: the RF generator produces a specific frequency RF power signal (e.g., 13.56MHz), with a fixed output impedance of 50Ω, and is equipped with a voltage and current sensor (VI sensor) to detect forward and reflected power; the RF cable is responsible for power transmission; and the impedance matcher converts the non-50Ω impedance at the load end to a 50Ω impedance at the input end to achieve impedance matching with the RF generator, minimize reflected power, and ensure efficient energy delivery to the RF coil. In actual processes, the load impedance is constantly changing due to parameters such as chamber pressure, gas flow rate, and plasma density; therefore, the impedance matcher needs to track and adjust the impedance in real time.

[0003] As semiconductor manufacturing processes continue to advance, advanced technologies place higher demands on the matching speed and accuracy of RF systems, highlighting the shortcomings of traditional impedance matching schemes. Currently, the mainstream impedance matching scheme is the L-type automatic matching circuit, which includes a parallel branch adjustable capacitor, a series branch adjustable capacitor, and an input sensor on the input side of the matching circuit. The two adjustable capacitors are controlled by a motor to adjust their values. The control unit collects voltage, current, and phase information through the input sensor, calculates the amplitude and phase errors of the input impedance relative to 50Ω, and then adjusts the capacitor values ​​to reduce these errors. However, this scheme has two major problems: First, the matching speed is slow, making it difficult to meet the requirements of advanced processes. Due to the strong coupling effect between the parallel and series branch adjustable capacitors, adjusting either capacitor simultaneously affects both the amplitude and phase errors, requiring multiple iterations to achieve matching. This results in a lengthy matching process, making it unsuitable for processes with stringent matching speed requirements. Second, it is highly dependent on the accuracy of the input sensor, increasing design and usage costs. The matching effect depends entirely on the measurement accuracy of the input sensor. However, the strong radio frequency interference environment in which the matcher operates can easily affect the sensor performance. To ensure accuracy, a lot of costs need to be invested in sensor design, electromagnetic shielding, and regular calibration. This also increases the difficulty of manufacturing and maintaining the matcher, which is not conducive to improving the economic efficiency of the equipment.

[0004] In summary, existing L-type circuit automatic matching devices can no longer meet the requirements of advanced ICP equipment for matching speed, accuracy, and cost control. Developing a fast automatic impedance matching system and matching method that can solve the above problems has become an urgent need in the field of integrated circuit manufacturing equipment. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention provides a fast automatic impedance matching system and matching method.

[0006] According to a first aspect of the technical solution of the present invention, the present invention specifically provides a fast automatic impedance matching system, including a frequency-tunable radio frequency power supply module, a radio frequency cable module, a matching module, and a chamber load module: The tunable RF power supply module includes a power supply unit, a power amplifier unit, a VI sensor, and a power control unit. The power supply unit generates tunable RF signals, the power amplifier unit amplifies the signal power, and the VI sensor is located at the output of the power amplifier to measure the voltage amplitude V, current amplitude I, and phase difference φ in real time, and to calculate the output impedance. The power control unit receives the frequency adjustment signal from the matching module and dynamically adjusts the RF output frequency; the output of the adjustable RF power module is connected to the input of the matching module via an RF cable module. The radio frequency cable module is used to transmit radio frequency power and signals. The radio frequency cable module is connected to the output terminal of the tunable radio frequency power supply module and connected to the input terminal of the matching module. The matching module includes an adjustable capacitor element C1 and a control unit. The adjustable capacitor element C1 is used to adjust the capacitance value through a motor to change the impedance value at the output of the matching unit. The control unit is used to read the radio frequency information of the adjustable frequency power supply and calculate the load impedance parameters. The control unit is connected to the control module of the adjustable frequency power supply through a communication bus. The chamber load module includes a radio frequency coil and a plasma load, which are used to receive the matching radio frequency power output by the matching module and to excite and maintain the inductively coupled plasma; the chamber load module is connected to the output terminal of the matching module to form a load circuit.

[0007] Furthermore, the load impedance parameters, including the load resistance R and load inductance L, are calculated, and a motor control signal is output to adjust the capacitance value of C1. At the same time, a power supply frequency adjustment signal is output to the adjustable frequency RF power supply to achieve closed-loop control of impedance matching.

[0008] Furthermore, the adjusting elements of the adjustable capacitor element C1 include a stepper motor, a motor capacitor matching assembly, a motor drive board, and an encoder.

[0009] Furthermore, the control unit is used to calculate the output impedance of the RF power supply based on the measurement data of the VI sensor, derive the input admittance of the matching device according to the cable parameters, analyze the load resistance R and inductance L, solve for the target frequency and target capacitance, and synchronously output the frequency adjustment signal to the power supply control unit and the capacitance adjustment signal to the adjustable capacitor element C1 to achieve single-step impedance matching.

[0010] Furthermore, the formulas used to solve for the target frequency and target capacitance include: ; ; Where R is the load resistance, L is the load inductance, ω1 is the target angular frequency, and ω1 = 2πf1; .

[0011] Furthermore, the formula used by the control unit to calculate the load resistance R and the load inductance L includes: ; ; Where G0 is the real part of the admittance, ω0 is the initial angular frequency, ω0 = 2πf0, f0 is the initial frequency, and M0 is an intermediate variable.

[0012] This invention also discloses a fast automatic impedance matching method, applied to the aforementioned fast automatic impedance matching system, comprising the following steps: (a) Output RF power at an initial frequency f0, and measure |V|, |I|, and φ using a VI sensor; (b) Calculate the output impedance Z of the RF power supply s ; (c) Deriving the matching circuit input impedance Z based on cable parameters in ; (d) Transformation Z in To guide Y in Y in =G0+jB0; (e) Analyze the load resistance R and inductance L; (f) Solve for the target frequency value f1 and the target capacitance value C1; (g) Adjust the RF power supply output frequency to f1 and the capacitor value to C1.

[0013] Furthermore, the objective parameter calculation in step (f) satisfies: ; Where ω1 is the target angular frequency, .

[0014] Furthermore, in pulse mode: Step (a) Increase pulse frequency and duty cycle for synchronous sampling; Step (g) combines pulse rising edge prediction to determine the timing of adjustments.

[0015] Furthermore, in step (e), the analysis of load parameters R and L is performed using a lookup table method or Newton's iteration method instead of real-time calculation; the analytical formula for step (e) is: ； ; Where G0 is the real part of the admittance, ω0 is the initial angular frequency, ω0 = 2πf0, f0 is the initial frequency, and M0 is an intermediate variable.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention significantly improves the efficiency of semiconductor device testing through innovative design.

[0017] 2. The technical solution of the present invention realizes a single-step matching mechanism, which greatly speeds up the matching speed; the hardware structure is highly simplified, requiring only a single adjustable capacitor element, effectively reducing system complexity and manufacturing and maintenance costs; at the same time, it eliminates the need for a dedicated input sensor inside the matcher, and instead reuses the built-in sensor of the RF power supply, saving design difficulty and calibration costs.

[0018] 3. The system of this invention possesses strong adaptive capabilities, flexibly adapting to different equipment sizes and process modes, including continuous wave and pulse operation. In pulse scenarios, the stability and reliability of the process are ensured through optimized transient response mechanisms. These advantages collectively enhance overall performance, making this invention widely applicable in advanced semiconductor manufacturing. Attached Figure Description

[0019] To more clearly illustrate the embodiments of the present invention or the technical solutions in 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 merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of an automatic impedance matching system for ICP equipment according to the present invention; Figure 2 This is a schematic diagram of an automatic impedance matching method for ICP equipment according to the present invention; Figure 3 This is a schematic diagram of the L-type circuit automatic matching device in Comparative Example 1. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 are within the scope of protection of the present invention.

[0022] The concepts involved in this application will first be described with reference to the accompanying drawings. It should be noted that the following descriptions of various concepts are only for the purpose of making the content of this application easier to understand and do not constitute a limitation on the scope of protection of this application; furthermore, the embodiments and features in the embodiments of this application can be combined with each other unless otherwise specified. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] Example 1 like Figure 1 As shown, this embodiment provides a fast automatic impedance matching system, including a frequency-tunable RF power supply module 10, an RF cable module 20, a matching module 30, and a chamber load module 40.

[0024] The tunable RF power supply module 10 includes a power supply unit 101, a power amplifier unit 102, a VI sensor 103, and a power control unit 104. The power supply unit 101 generates a tunable RF signal, the power amplifier unit 102 amplifies the signal power, and the VI sensor 103 is located at the output of the power amplifier to measure the voltage amplitude |V|, current amplitude |I|, and phase difference φ in real time, and to calculate the output impedance. , The power control unit 104 receives the frequency adjustment signal from the matching module 30 and dynamically adjusts the RF output frequency. The output of the adjustable RF power module 10 is connected to the input of the matching module 30 via the RF cable module 20.

[0025] The RF cable module 20 is used to transmit RF power signals. It has a length of 1 and a characteristic impedance Z0 of 50Ω. The RF cable module 20 is connected as follows: one end is connected to the output terminal of the adjustable frequency RF power supply module 10, and the other end is connected to the input terminal of the matching unit module 30, forming a signal transmission channel. The function of the RF cable is to transmit impedance information; its input impedance... Through formula The calculated value (where β = 2π / λ, and λ is the signal wavelength) is used to derive the load admittance Yin; where β is the characteristic impedance of the radio frequency cable, which means the characteristic impedance of the cable, and the unit is ohms; β is the phase constant, which means the rate of change of the phase of the signal in the cable, and the unit is radians per meter. λ represents the length of the radio frequency cable, which is its physical length in meters; λ represents the wavelength of the radio frequency signal in a vacuum or medium, also in meters. The impedance at the RF power supply output is in ohms. It is an imaginary number with no unit; The input impedance of the matching circuit is the complex impedance value at the input of the matching circuit, expressed in ohms.

[0026] The matching module 30 includes an adjustable capacitor element C1 and a control unit 301. The adjustable capacitor element C1 is used to adjust its capacitance value via a motor to change the admittance value at the output of the matching unit. The control unit 301 is used to read the RF frequency information of the adjustable frequency power supply 10, calculate the load impedance parameter R and the load inductance parameter L, and output a motor control signal to adjust the capacitance value of the adjustable capacitor element C1. Simultaneously, it outputs a power supply frequency adjustment signal to the adjustable frequency power supply 10 to achieve closed-loop control of impedance matching. The control unit and the control module of the adjustable frequency power supply 10 are connected via a communication bus to achieve data interaction, such as the transmission of frequency f0 and impedance data Zs.

[0027] The chamber load module 40 includes a radio frequency coil and a plasma load, used to receive the matched radio frequency power output from the matching module 30, and to excite and maintain the inductively coupled plasma. The impedance characteristics of the chamber load are as follows: Where R is the real resistance, L is the inductance, and ω0 = 2πf0 is the angular frequency. The chamber load module 40 is connected directly to the output of the matching module 30 to form a load loop, and its impedance changes are compensated in real time by a matching algorithm.

[0028] Specifically, the adjustable capacitor C1 can be a stepper motor, relay, or voltage-controlled diode, with a capacitance range of 0-500pF (the specific configuration is determined based on the load network calculation); the RF cable length l can be dynamically compensated based on the wavelength β = 2π / λ (λ is the signal wavelength); in the ICP scenario (400k~100MHz), the load inductor L can be a fixed metal part (such as a spiral type); in the CCP scenario (400k~100MHz), the matching unit needs to be connected in series with an inductor in the RF network, and the load is a capacitive electrode (such as a metal electrode plate).

[0029] The technical effects of the above solution are as follows: Improved single-step matching speed: By combining frequency adjustment and single-capacitor regulation, the strong coupling effect of traditional dual capacitors is eliminated, achieving one-step matching and increasing matching speed to meet the fast response requirements of demanding processes such as semiconductor manufacturing. The technical principle originates from the control unit's algorithm, which directly calculates the target frequency f1 and capacitance C1 from the measured impedance, avoiding iterative adjustments.

[0030] Simplified network structure: Compared with traditional matching circuits (≥2 adjustable elements), only one adjustable capacitor element C1 is used, which simplifies the hardware complexity of the matching circuit, reduces manufacturing costs and maintenance difficulty. This technical solution is based on the design of matching circuit module 30, reducing the number of components and mechanical structure.

[0031] Eliminating input sensors reduces costs: By utilizing the built-in VI sensor in the tunable RF power module 10 to replace the internal sensors in the matching unit, the requirements for additional sensor design, calibration, and RF interference protection are reduced, thus lowering the cost of the matching unit. The technical principle is based on the reuse of the VI sensor and data sharing through communication, avoiding the accuracy dependence problem of the input sensor.

[0032] Example 2 This embodiment provides a fast automatic impedance matching system, specifically applied to 200mm or 300mm ICP semiconductor devices, based on Embodiment 1. The system composition is the same as in Embodiment 1, but the chamber load module 40 is optimized for wafer dimensions as follows: for 200mm devices, the load impedance R ranges from 10 to 100Ω, and L ranges from 0.1 to 1μH; for 300mm devices, R ranges from 5 to 50Ω, and L ranges from 0.05 to 0.5μH. The matching control unit has a pre-stored device parameter database and automatically calibrates the calculation algorithm according to the device type (200mm or 300mm) to ensure fast matching over a wide load range.

[0033] Specifically, the drive motor of the adjustable capacitor element C1 can be a high-precision stepper motor or a voltage-controlled diode to adapt to the high dynamic load of large-size equipment; the length l of the RF cable is fixed at 1-3m, and the matching control unit compensates for the cable effect through formula 2.

[0034] The technical effects of the above solution are: it can adapt to the size of the device, the matching speed is effectively improved in 300mm devices, and the one-step matching accuracy error is small.

[0035] Example 3 This embodiment provides a fast automatic impedance matching system, specifically targeting continuous wave (CW) and pulsed process modes, based on Embodiment 1. The system composition is the same, but the matching module 30 adds mode switching logic: in CW mode, the frequency adjustment step size is small (0.1MHz) to achieve stable matching; in pulsed mode, a fast scanning algorithm (frequency jump step size of 1MHz) is used, combined with C1 capacitance pre-adjustment, to adapt to high-frequency transient loads. Specifically, the VI sensor increases the sampling rate (to 1MS / s) in pulsed mode to ensure real-time performance; the adjustable capacitor element C1 is preferably a voltage-controlled diode or a relay array.

[0036] The technical benefits of the above solution are: improved pulse mode matching speed, which is achieved through high-frequency sampling and pre-adjustment mechanisms, thus avoiding overshoot.

[0037] Example 4 like Figure 2 As shown, this embodiment provides a fast automatic impedance matching method, applied to a fast automatic impedance matching system. The specific steps of the automatic detection method include: (a) The RF power supply outputs power at an initial frequency f0, and the VI sensor measures the voltage |V|, current |I|, and phase difference φ; (b) Calculate the impedance at the power supply output terminal , (Formula 1); where This refers to the voltage amplitude, which represents the magnitude of the output voltage of the radio frequency power supply, measured in volts. This represents the current amplitude, specifically the amplitude of the RF power supply's output current, measured in amperes. Phase difference, meaning the phase angle difference between voltage and current, in radians; This is the output impedance of the RF power supply, representing the complex impedance value at the power supply output, measured in ohms. (c) Calculate the input impedance of the matching unit front end based on the length l of the RF cable and the characteristic impedance Z0. , (Formula 2), where , To transmit the wavelength of the signal propagating on the line, This is the characteristic impedance of the transmission line, typically 50Ω; where β is the characteristic impedance of the radio frequency cable, which means the characteristic impedance of the cable, and the unit is ohms; β is the phase constant, which means the rate of change of the phase of the signal in the cable, and the unit is radians per meter. λ represents the length of the radio frequency cable, which is its physical length in meters; λ represents the wavelength of the radio frequency signal in a vacuum or medium, also in meters. The impedance at the RF power supply output is in ohms. It is an imaginary number with no unit; The input impedance of the matching circuit is the complex impedance value at the input of the matching circuit, expressed in ohms. (d) will Converted to admittance: (Formula 3); where The input admittance of the matched circuit is the reciprocal of the impedance, and its unit is Siemens. This represents the real part of the admittance, specifically the real number of the admittance (conductance), measured in Siemens units. This is the imaginary part of the admittance, meaning the imaginary portion of the admittance (susceptance), and the unit is Siemens; (e) Based on the current operating point and the measured admittance, the equivalent resistance R and equivalent inductance L of the load are calculated by calculating the intermediate variable M0. The formulas used are: ; (Equation 8) and (Formula 9); where The initial angular frequency is the angular frequency corresponding to the initial radio frequency, expressed in radians per second. R represents the initial capacitance value, signifying the initial capacitance of the adjustable capacitor in the matching circuit (before matching adjustment). L For load resistance, it means the equivalent resistance value of the chamber load; As an intermediate variable, consistent with R, emphasizing the load side, unit is ohms; The imaginary part of the admittance (susceptance) is the imaginary portion of the input admittance of the matched circuit, and its unit is Siemens. The load resistance is the equivalent resistance value of the chamber load, expressed in ohms. For load inductance, it represents the equivalent inductance value of the chamber load, measured in Henry.

[0038] (f) Calculate the target angular frequency value ω 11 And the target capacitance value C1: Substitute the calculated R and L into the analytical solution formula derived from the matching target equation (Formula 10) to directly solve for the target angular frequency ω1 and the target capacitance value C1 required to achieve matching (Z=50Ω); the formula used is: (Formula 10); where The target angular frequency is the angular frequency under the matching target, expressed in radians per second. The target capacitance value refers to the target capacitance value of the adjustable capacitor in the matching circuit, expressed in farads. The admittance under the matched condition is the admittance value at the output of the matched circuit, expressed in Siemens. (Formula 11); (Formula 12); in, The output frequency of the RF power supply is [value]; the load impedance of the chamber is [value]. ,in The real part of the impedance is... For the imaginary part of the impedance, For frequency The corresponding angular frequency, at which point the capacitance of the adjustable capacitor is... The matching is completed in one step by directly outputting the adjustment signal.

[0039] The technical effects of the above solution are as follows: the method of this embodiment is beneficial to improving the matching speed; the effect comes from the accurate calculation of load parameters, eliminating the need for iterative steps.

[0040] Specifically, the specific adjustment methods and formula derivation process are as follows: RF power supplies first use frequency Output power; at this time, the VI sensor inside the RF power supply collects the voltage and current amplitude. and phase difference Then the impedance at the output terminal of the RF power supply is... (Formula 1); If the length of the radio frequency cable is l The input impedance at the front end of the impedance matching circuit is (Formula 2); in, , To transmit the wavelength of the signal propagating on the line, This is the characteristic impedance of the transmission line, typically 50Ω.

[0041] Will Convert to admittance: (Formula 3); At this time, the load impedance of the chamber is ,in The real part of the impedance is... For the imaginary part of the impedance, For frequency The corresponding angular frequency, at which point the capacitance of the adjustable capacitor is... .

[0042] Then based on the load impedance and The calculated front-end admittance of the matcher is (Formula 4); Substituting (4) into (3), we get (Formula 5); (Formula 6); After transforming the formula, we get: (Formula 7); Substituting (6) into (4), we get (Formula 8); (Formula 9); The control strategy is as follows: Assuming impedance matching, the RF power supply output frequency is The capacitance of the adjustable capacitor element is The objective of the control strategy is then determined by measurement. and known and The load resistance is calculated from information such as (8) and (9). and inductor Based on this, we can find the system that makes it match. and .

[0043] In frequency and capacitors Under the conditions, Matched with the 50Ω output impedance of the RF power supply, therefore the admittance at this point... S, can be obtained (Formula 10); Solving (10) yields the following results. (Formula 11); (Formula 12); in, This is the output frequency value of the RF power supply.

[0044] Example 5 This embodiment provides a fast automatic impedance matching method. Based on Embodiment 4, the calculation process is optimized: in step (e), a lookup table method or approximate algorithm is used to solve for R and L, reducing the real-time calculation load. The matching control unit pre-stores typical load curves and uses f0 and C0 for fast indexing.

[0045] The technical effects of the above solution are: improved matching accuracy through computational optimization; the effect stems from hardware acceleration and pre-stored data, enhancing practicality.

[0046] Example 6 This embodiment provides a fast automatic impedance matching method, which is specifically designed for pulse mode based on embodiment four: In step (a), pulse synchronous sampling is added (measuring |V|, |I|, φ during the duty cycle); In step (f), f1 and C1 are adjusted in combination with pulse rising edge prediction to achieve zero-delay matching.

[0047] Specifically, when the pulse repetition frequency is 1-100kHz, adaptive filtering is used to reduce noise interference; the method can be combined with the system of Example 3, using voltage-controlled diodes for fast response.

[0048] The technical effects of the above solution are as follows: through the pulse synchronization mechanism, the matching speed is increased by 60% under a 100kHz pulse; the effect stems from timing optimization, which avoids the accumulation of reflected power.

[0049] Comparative Example 1 like Figure 3As shown, Comparative Example 1 is an L-type circuit automatic matching unit. The control unit reads the measurement data (voltage, current, phase) from the input sensor, calculates the amplitude error and phase error of the input impedance relative to 50Ω, and adjusts the capacitance values ​​of adjustable capacitors C1 and C2 through an iterative algorithm. Due to the strong coupling effect of adjustable capacitors C1 and C2, adjusting either capacitor will simultaneously affect the amplitude and phase errors, requiring multiple iterations to achieve matching. Furthermore, it relies on high-precision input sensors, is susceptible to radio frequency interference, and requires additional design, calibration, and shielding measures. While suitable for traditional ICP equipment, it cannot meet the speed and accuracy requirements of advanced semiconductor manufacturing processes.

[0050] In summary, this invention provides a testing scheme that can automatically simulate the dynamic impedance characteristics of process chambers, support multi-port testing, and has self-calibration capabilities, thereby solving the problems of incomplete performance evaluation and low testing efficiency of RF matching devices.

[0051] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. A fast automatic impedance matching system, characterized in that, Includes a frequency-tunable RF power supply module (10), an RF cable module (20), a matching module (30), and a chamber load module (40): The tunable RF power module (10) includes a power supply unit (101), a power amplifier unit (102), a VI sensor (103), and a power control unit (104). The power supply unit (101) generates a tunable RF signal, the power amplifier unit (102) amplifies the signal power, and the VI sensor (103) is located at the output of the power amplifier to measure the voltage amplitude |V|, current amplitude |I|, and phase difference φ in real time, and to calculate the output impedance Z. S The power control unit (104) is used to receive the frequency adjustment signal from the matching module (30) and dynamically adjust the RF output frequency; the output of the adjustable RF power module (10) is connected to the input of the matching module (30) through the RF cable module (20); The radio frequency cable module (20) is used to transmit radio frequency power and signals. The radio frequency cable module (20) is connected to the output end of the adjustable frequency radio frequency power supply module (10) and connected to the input end of the matching module (30). The matching module (30) includes an adjustable capacitor element (C1) and a control unit (301). The adjustable capacitor element (C1) is used to adjust the capacitance value through a motor to change the impedance value at the output of the matching unit. The control unit (301) is used to read the radio frequency information of the adjustable frequency radio power module (10) and calculate the load impedance parameters. The control unit is connected to the control module of the adjustable frequency radio power module (10) through a communication bus. The chamber load module (40) includes a radio frequency coil and a plasma load, which are used to receive the matching radio frequency power output by the matching module (30), excite and generate inductively coupled plasma and maintain the plasma; the chamber load module (40) is connected to the output terminal of the matching module (30) to form a load circuit; The length of the RF cable module (20) is l, and its characteristic impedance is Z0. The input impedance of the RF cable module (20) is calculated by the following formula: ； Where β = 2π / λ, λ is the signal wavelength, used to derive the load admittance Y. in Where Z0 is the characteristic impedance of the RF cable, meaning the characteristic impedance of the cable, in ohms; β is the phase constant, meaning the rate of phase change of the signal in the cable, in radians per meter; l is the length of the RF cable, meaning the physical length of the cable, in meters; λ is the signal wavelength, meaning the wavelength of the RF signal in a vacuum or medium, in meters; Z S The impedance at the RF power supply output is in ohms; j is an imaginary number with no unit; Z in The input impedance of the matching circuit is the complex impedance value at the input of the matching circuit, expressed in ohms.

2. The fast automatic impedance matching system according to claim 1, characterized in that, The load impedance parameters, including resistance R and inductance L, are calculated. A motor control signal is output to adjust the capacitance value of the adjustable capacitor element (C1). At the same time, a power supply frequency adjustment signal is output to the adjustable frequency RF power supply module (10) to achieve closed-loop control of impedance matching.

3. The fast automatic impedance matching system according to claim 1, characterized in that, The adjustable capacitor element (C1) includes a stepper motor, a motor capacitor matching assembly, a motor drive board, and an encoder.

4. The fast automatic impedance matching system according to claim 1, characterized in that, The control unit (301) is used to calculate the impedance of the RF power supply output terminal based on the measurement data of the VI sensor (103), derive the matching unit input admittance according to the cable parameters, analyze the load resistance R and inductance L, solve the target frequency and target capacitance, and synchronously output the frequency adjustment signal to the power control unit (104) and the capacitance adjustment signal to the adjustable capacitor element (C1) to achieve single-step impedance matching.

5. A fast automatic impedance matching method, applied to the fast automatic impedance matching system according to any one of claims 1-4, characterized in that, Includes the following steps: (a) Output RF power at an initial frequency f0 and measure |V|, |I|, φ using VI sensor (103); (b) Calculate the output impedance Z of the RF power supply S ; (c) Deriving the matching circuit input impedance Z based on cable parameters in ; (d) Transformation Z in To guide Y in Y in =G0+jB0; (e) Analyze the load resistance R and inductance L; (f) Solve for the target frequency value f1 and the target capacitance value C1; (g) Adjust the RF power supply output frequency to f1 and the capacitor value to C1.

6. The rapid automatic impedance matching method according to claim 5, characterized in that, In pulse mode: Step (a) Increase pulse frequency and duty cycle for synchronous sampling; Step (g) combines pulse rising edge prediction to determine the timing of adjustments.

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