Device and method for calibrating alternating current signal sensor

Abstract

The invention discloses a device and method for calibrating an alternating current signal sensor, and belongs to the technical field of semiconductor equipment detection, and the device for calibrating the alternating current signal sensor comprises a radio frequency conduction module, a signal processing module and a shielding grounding module, the radio frequency conduction module establishes a radio frequency energy transmission channel with 50 ohm impedance through a conductive column and a symmetrical radio frequency interface; the signal processing module comprises a single-chip microcomputer unit and a communication interface, calculates real current and voltage values through a power value formula, and achieves calibration parameter fitting. The shielding grounding module constructs an electromagnetic shielding environment through the aluminum alloy shell and the elastic conductive clamp. The circuit has the advantages of low cost, no need of an external calibration piece, high interference resistance, support of high power and full-band (50Hz-30MHz) application and the like, is suitable for semiconductor equipment and power devices, and improves the calibration precision and efficiency.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor equipment testing technology, and specifically relates to a device and method for calibrating an AC signal sensor. Background Technology

[0002] In modern industrial production and scientific research, AC signal sensors, as key components, are widely used in many important industries such as power transmission, semiconductor manufacturing, and communications. The accuracy of their measurement results plays a decisive role in the stable operation and performance of the entire device. In semiconductor equipment manufacturing, the radio frequency power output from the RF power supply is transmitted to the impedance matching circuit via a coaxial cable, and finally to the metal electrodes or coils to excite plasma. In this process, the accurate measurement of RF current and voltage by the AC signal sensor directly affects the characteristics of the plasma, and thus influences the quality and effect of surface treatment processes. Integrated circuit manufacturing typically involves a variety of surface treatment processes, including but not limited to photolithography, etching, thin film deposition, chemical mechanical polishing, electroplating, epitaxial growth, cleaning, and ion implantation. Some etching and thin film deposition equipment generates a strong local electromagnetic field by transmitting high-frequency electromagnetic energy to metal electrodes or coils. This field, or electromagnetic induction, accelerates a small number of free electrons in the neutral gas within the reaction chamber, causing them to collide frequently with neutral particles to produce a large number of charged particles, including electrons, positive ions, and negative ions. The ionization process continues, ultimately forming a plasma—an aggregate containing electrons, positive ions, negative ions, neutral atoms and molecules, and free radicals. The wafer to be processed is then immersed in the plasma, and the charged particles and free radicals within the plasma are used to complete surface treatment processes such as etching, thin film deposition, and resist removal.

[0003] The high-frequency electromagnetic energy required to generate the aforementioned plasma is typically in the radio frequency band, with typical frequencies of 400kHz / 2MHz / 13.56MHz / 27.12MHz / 40MHz / 60MHz and typical power ranges of 200-20000W. It is generally generated by a specific device, namely a radio frequency power supply. The radio frequency power output from the power supply is transmitted via a coaxial cable to an impedance matching circuit. After impedance matching, it is transmitted to metal electrodes or coils, thereby exciting the plasma, such as... Figure 1 As shown.

[0004] According to the principles of radio frequency (RF) circuits, RF energy transmission must pass through some kind of impedance matching device, structure, or network to ensure that the load impedance matches the internal resistance of the RF power supply; otherwise, varying degrees of energy loss will occur. In integrated circuit manufacturing equipment, this impedance matching device is typically located between the RF power supply and the metal electrodes or coils, such as... Figure 1 As shown.

[0005] like Figure 2As shown, an impedance matching device typically consists of a phase amplitude sensor 202, a matching network 203, and a current and voltage sensor 204. The phase amplitude sensor 202 detects the load impedance at the RF power supply downstream in real time, while the matching network 203 adjusts the values ​​of its electrical components in real time based on the detection results. The two work together to achieve impedance matching. The current and voltage sensor 204 detects the RF current and voltage transmitted to the metal electrode in real time. As mentioned earlier, plasma generation depends on the RF electromagnetic field on the metal electrode. Therefore, the magnitude and stability of the RF current and voltage directly determine the properties of the generated plasma, such as electron density, electron temperature, ion energy, and ionization rate, thus indirectly determining whether the surface treatment process meets the standards, and has significant indicative value. Figure 2 In the accompanying drawings, reference numerals 205 and 206 represent auxiliary components and grounding terminals of the matching network, respectively, and should be further described in the instruction manual. Specifically, 205 is an adjustable capacitor element, and 206 is a shielded grounding connection point.

[0006] Therefore, the accuracy of the measurement results from the current and voltage sensor 204 becomes crucial. Figure 3 The internal structure of the current-voltage sensor 204 is shown. This sensor is typically fabricated on a PCB board. A conductive material 302 (usually metal) is coated around a hollow circular hole 310 as an RF voltage pickup probe. A coil 301, also made of conductive material (usually metal), is wound around the voltage probe 302 as a current pickup probe. The voltage and current are picked up from a charged conductor 303, specifically the RF energy output port of the impedance matching circuit 207, which is typically cylindrical and made of copper. This structure constitutes the probe portion 309 of the sensor. The acquired voltage and current signals are transmitted via wires 304 and 305 to the analog signal processing unit 306 for filtering, waveform conversion, analog-to-digital conversion, and other processing. The digital quantities PCB_V and PCB_I are output to the digital signal processing unit 307. Calibration parameters a1, b1, a2, and b2 are transmitted from outside to unit 307. After processing, the accurate RF voltage V = PCB_V × a1 + b1 and RF current I = PCB_I × a2 + b2 are obtained, and then transmitted to the matching unit main control unit 308. Because sensor 204 is a non-contact design and does not directly contact the measured object, it cannot directly output accurate current and voltage values; these values ​​must be calculated using the methods described above. Simultaneously, the analog signal processing unit 306 can also transmit signals PCB_V and PCB_I externally.

[0007] To obtain calibration parameters a1, b2, a2, b2, sensor 204 needs to be calibrated. A commonly used method is to connect an external calibration component 208 between the impedance matching device 207 and the simulated load 209. The simulated load 209 is a device that simulates the impedance of a chamber and plasma load, containing several capacitors, inductors, or resistors of variable capacitance connected in series or parallel. Figure 4 As shown. Calibration component 208 is typically a highly customized commercial RF parameter sensor that is calibrated before leaving the factory and can output accurate RF current, voltage, frequency, harmonic levels, and other parameters. Once the RF power supply is turned on and impedance matching is complete, calibration component 208 can output real-time, accurate RF current and voltage values ​​V. cal , I cal Assuming the digital values ​​of the current and voltage output by the sensor are PCB_V and PCB_I, the above four parameters form a corresponding relationship. Wherein, V... cal =V rms The physical meaning is the effective value of the radio frequency voltage; I cal =I rms The physical meaning is the effective value of the radio frequency current. By changing the output power of the radio frequency power supply and repeating the test, after obtaining several sets of corresponding relationships, the calibration parameters a1, b1, a2, b2 can be fitted and calculated, so that the sensor 204 outputs a true and accurate radio frequency current and voltage value.

[0008] The existing technology has the following problems: 1. The cost of dedicated RF external calibration components is high, typically ranging from tens of thousands to hundreds of thousands of yuan, increasing R&D and design costs; 2. An interface for an external calibration component 208 needs to be designed between the end of the matching unit 207 and the analog load 209, increasing system complexity and R&D and design costs; 3. It has weak anti-interference capabilities and is easily affected by the RF environment. Since the calibration component 208 is directly connected to the matching unit 207 and the analog load 209, it is within the RF energy transmission link, and its surrounding environment has strong electromagnetic radiation. If the casing of the calibration component 208 is not grounded or improperly grounded, electromagnetic interference will be introduced, leading to distorted measurement results. In addition, if poorly designed, the interface or connecting cable between the calibration component 208 and the matching unit 207 or the analog load 209 may become a "receiving antenna" for electromagnetic radiation, which will also introduce electromagnetic interference; 4. Currently commercially available RF sensors cannot withstand RF power higher than 15kW when measuring current and voltage, which limits their measurable power range to 0-15kW, making it impossible to measure current and voltage at RF power higher than 15kW.

[0009] Therefore, developing a low-cost, interference-resistant, and wide-power-range-adaptable device and method for calibrating AC signal sensors has become an important issue that the industry urgently needs to address. Summary of the Invention

[0010] Based on the technical problems existing in the prior art, the purpose of this invention is to provide a device and method for calibrating AC signal sensors, so as to solve the problems of high cost of dedicated external calibration components for radio frequency, high R&D and design costs due to the design of an interface for external calibration components between the matching end and the analog load, weak anti-interference ability, susceptibility to radio frequency environment, and inability of commercial radio frequency sensors to withstand radio frequency power higher than 15kW when measuring current and voltage.

[0011] To solve the above-mentioned technical problems, according to the first aspect of the technical solution of the present invention, an apparatus for calibrating an AC signal sensor is provided, which includes a radio frequency conduction module, a signal processing module and a shielding grounding module; The radio frequency conduction module is used to establish a radio frequency energy transmission channel with a standard impedance of 50Ω. It includes conductive pillars, symmetrical radio frequency interfaces and an insulating structure. The radio frequency power supply is connected to the top of the conductive pillars through the symmetrical radio frequency interfaces, and a fixed load is connected to the bottom of the conductive pillars. The insulating structure isolates the conductive pillars from the outer shell. The signal processing module is used to calculate the actual current and voltage values ​​based on the power value, and includes a microcontroller unit and a communication interface; The shielding grounding module is used to construct an electromagnetic shielding environment. It includes an aluminum alloy shell and an elastic conductive clamp. The shell completely encloses the radio frequency conduction module and is connected to the ground through a grounding terminal. The elastic conductive clamp fixes the sensor and is in communication with the shell.

[0012] Furthermore, the microcontroller unit processes the PCB_V and PCB_I signals output by the AC signal sensor based on a formula, and outputs calibration parameters. The formula is: and Where P is the radio frequency power. V rms Where R is the effective value of the RF voltage, R is the impedance of the fixed load, and I is the effective value of the RF voltage. rms This is the effective value of the radio frequency current.

[0013] Furthermore, the symmetrical radio frequency interface is an HN type, N type, LC type or SQS type interface.

[0014] Furthermore, it also includes a frequency adaptation module for adapting to the full frequency band of 50Hz-30MHz. The frequency adaptation module includes replaceable conductive pillars and a multi-band algorithm library; wherein replaceable conductive pillars with a diameter ≥30mm are used for the low frequency band of 50Hz-100kHz, and replaceable conductive pillars with a diameter of 5-10mm are used for the high frequency band of 1-30MHz. The multi-band algorithm library is integrated into the microcontroller unit.

[0015] Furthermore, it also includes a nonlinear calibration module for processing nonlinear sensor calibration. The nonlinear calibration module includes a piecewise power controller and a quadratic function fitting unit. The piecewise power controller is connected to the RF power supply and adjusts the output power. The exponential function fitting unit is integrated into the microcontroller unit and processes the PCB_V / I signal through the microcontroller unit to realize nonlinear calibration calculation. Data is collected in low / high power segments during the calibration process.

[0016] Furthermore, the microcontroller unit performs parameter fitting through linear regression to obtain calibration parameters.

[0017] Furthermore, the nonlinear calibration module uses the least squares method to solve for parameters a, b, and c to handle nonlinear relationships, and the fitting index used is V. cal =a·e b·PCB_V +c; where V cal is the true effective value of the radio frequency voltage after calibration of the AC signal sensor, a is the amplitude scaling factor of the nonlinear calibration, b is the nonlinear response coefficient of the nonlinear calibration, c is the offset correction parameter of the nonlinear calibration, and PCB_V is the original digital voltage output of the AC signal sensor.

[0018] According to a second aspect of the present invention, the present invention provides a method for calibrating an AC signal sensor, which is applied to the aforementioned apparatus for calibrating an AC signal sensor, and includes the following steps: Step S01, Radio Frequency Conduction: Fix the sensor around the conductive post, and input multiple sets of power values ​​to the conductive post through the symmetrical radio frequency interface; Step S02, Signal Processing: Read the PCB_Vn and PCB_In signals output by the sensor, based on the formula... and Calculate the actual current and voltage values, where P is the radio frequency power. V rms Where R is the effective value of the RF voltage, R is the impedance of the fixed load, and I is the effective value of the RF voltage. rms This is the effective value of the radio frequency current; Step S03, Parameter Fitting: For (PCB_V) n V cal ) and (PCB_I n ,I cal The exponential function V was fitted using the least squares method. cal =a·e b·PCB_V +c, solve for parameters a, b, c; where V cal is the true effective value of the radio frequency voltage after calibration of the AC signal sensor, a is the amplitude scaling factor of the nonlinear calibration, b is the nonlinear response coefficient of the nonlinear calibration, c is the offset correction parameter of the nonlinear calibration, and PCB_V is the original digital voltage output of the AC signal sensor.

[0019] Furthermore, in step S01, the symmetrical radio frequency interface is an HN type interface, and the radio frequency energy transmission direction can be from top to bottom or from bottom to top; the calculation process in step S02 is executed by the microcontroller unit of the signal processing module, and the radio frequency power value P is received through the communication interface.

[0020] Furthermore, it also includes a frequency adaptation step: replacing the diameter of the conductive post to adapt to the 50Hz-100kHz or 1-30MHz frequency band, and automatically switching the impedance mode through a multi-band algorithm library.

[0021] Compared with existing technologies, this invention has the following advantages: It establishes a standard 50Ω impedance channel through a radio frequency conduction module, directly calculating the true value using the radio frequency power supply value, eliminating the need for commercial radio frequency sensors and significantly reducing R&D costs. Furthermore, it integrates electromagnetic shielding through a shielded grounding module, eliminating the need for external calibration component interface design and reducing system complexity. The outer casing completely encloses the radio frequency conduction module and connects to the ground via a grounding terminal, eliminating electromagnetic radiation interference and ensuring measurement accuracy. The signal processing module calculates the true value based on impedance matching principles, combined with linear regression, achieving calibration accuracy superior to traditional methods. The frequency adaptation module, through replaceable conductive pillars and a multi-band algorithm library, is compatible with semiconductor equipment and power systems, overcoming domain limitations. A fixed load ensures zero-reflection transmission, supporting high-power industrial scenarios and solving the 0-15kW power limit issue of commercial sensors. The segmented power controller collects data in high and low power segments, and the quadratic function fitting unit handles complex relationships, shortening calibration time. A single device can calibrate multiple sensors simultaneously, improving efficiency. Attached Figure Description

[0022] 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.

[0023] Figure 1 This is a schematic diagram of the radio frequency device connection; Figure 2 This is a diagram showing the internal components of an impedance matching circuit. Figure 3The diagram shows the internal structure of the current and voltage sensor. The formulas in the diagram are linear calibration formulas (used for linear sensors or as initial calibration): Actual RF voltage value calculation formula: V = PCB_V × a1 + b1; Actual RF current value calculation formula: I = PCB_I × a2 + b2; where a1 and a2 are linear scaling factors used to correct sensor gain error; b1 and b2 are zero-point offset factors used to compensate for sensor zero-point drift. Figure 4 This is a schematic diagram of the connection to the external calibration component; Figure 5 This is a cross-sectional view of the internal structure of the calibration device; Figure 6 Side view of the calibration device; Figure 7 Top view of the calibration device; Figure 8 Diagram showing the working connection of the calibration device; Figure 9 Calibration flowchart; Figure 10 A diagram of a device for calibrating an AC signal sensor. Detailed Implementation

[0024] 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.

[0025] 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.

[0026] Example 1 This invention addresses the problems of high cost, weak anti-interference capability, and power limitation in existing calibration technologies by providing an innovative solution. For example... Figure 5 and Figure 6 As shown, this embodiment provides a device for calibrating an AC signal sensor, which includes a radio frequency conduction module 10, a signal processing module 20, and a shielded grounding module 30.

[0027] The radio frequency conduction module 10 includes a conductive post 406, a symmetrical radio frequency interface 402, and an insulating structure 404. The radio frequency conduction module 10 is used to establish a radio frequency energy transmission channel with a standard impedance of 50Ω. The radio frequency power supply is connected to the top of the conductive post 406 through the symmetrical radio frequency interface 402, and the bottom of the conductive post 406 is connected to a fixed load through the symmetrical radio frequency interface 402. The insulating structure 404 physically isolates the conductive post 406 from the outer shell 408.

[0028] The signal processing module 20 includes a microcontroller unit 410 and a communication interface 409. The signal processing module 20 is used to calculate the actual current and voltage values ​​based on the power value. The sensor 204 is connected to the input port of the microcontroller unit 410 through a data cable. The communication interface 409 transmits the radio frequency power value to the microcontroller unit 410. The microcontroller unit 410 outputs calibration parameters to the sensor 204.

[0029] The shielding grounding module 30 includes an aluminum alloy shell 408 and an elastic conductive clamp 407. The shielding grounding module 30 is used to construct an electromagnetic shielding environment. The shell 408 completely encloses the radio frequency conduction module 10. The elastic conductive clamp 407 fixes the sensor 204 and is in communication with the shell 408. The shell 408 is connected to the ground through a grounding terminal.

[0030] Specifically, the signal processing module 20 calculates the actual current and voltage values ​​based on the following formula: and , Where V cal For the true voltage, I cal P is the true current; P is the RF power; and R is the fixed load impedance.

[0031] Specifically, the symmetrical radio frequency interface 402 is an HN type interface.

[0032] The technical principle of the above scheme is as follows: According to the principle of radio frequency circuits, when impedance matching is achieved, the current and voltage on the radio frequency transmission path can be calculated using formulas (1) and (2), where P is the radio frequency power and I is the voltage. rms V is the effective value of the radio frequency current. rms Here, R is the effective value of the RF voltage, and R is the impedance of the fixed load 210Ω, i.e., the internal resistance of the RF power supply, which is a fixed value of R = 50Ω in most cases. Therefore, by obtaining the RF power P, the corresponding I can be calculated. rms and V rms To obtain the true and accurate current and voltage values: V cal =V rms , I cal =I rms The core device of this unit is generally a programmable microcontroller (MCU), which can quickly complete calculations and other complex tasks. Formula (1) is... Formula (2) is .

[0033] The technical advantages of the above solution are: the radio frequency conduction module replaces the external calibration components, solving the problems of high cost and complex structure; the signal processing module overcomes power limitations; and the shielded grounding module eliminates electromagnetic interference.

[0034] Example 2 like Figure 7 As shown, this embodiment provides a device for calibrating an AC signal sensor. Based on Embodiment 1, the device for calibrating an AC signal sensor further includes a frequency adaptation module 40. The frequency adaptation module 40 includes replaceable conductive pillars and a multi-band algorithm library for adapting to the full frequency band of 50Hz-30MHz.

[0035] Specifically, the replaceable conductive post with a diameter ≥30mm is a low-frequency thick post, which is connected to the symmetrical RF interface 402 for 50Hz-100kHz; the replaceable conductive post with a diameter 5-10mm is a high-frequency thin post, which is connected to the symmetrical RF interface 402 for 1-30MHz; the algorithm library is integrated into the microcontroller unit 410 to automatically switch impedance modes.

[0036] The technical effect of the above technical solution is to enable cross-domain application of semiconductor equipment and power devices.

[0037] Example 3 This embodiment provides a device for calibrating an AC signal sensor. Based on Embodiment 1, the device for calibrating an AC signal sensor further includes a nonlinear calibration module 50. The nonlinear calibration module 50 includes a piecewise power controller and a quadratic function fitting unit. The nonlinear calibration module 50 is used to process nonlinear sensor calibration. The power controller is connected to the RF power supply to regulate the output. The exponential function fitting unit is integrated into the microcontroller unit 410 and relies on the microcontroller unit 410 to process the PCB_V / I signal and complete the nonlinear fitting calculation. The calibration process collects data in low / high power segments.

[0038] The technical advantage of the above scheme is that it can complete the traditional nonlinear calibration task in a shorter time.

[0039] Example 4 like Figure 9 As shown, this embodiment provides a method for calibrating an AC signal sensor, applied to an apparatus for calibrating an AC signal sensor. The method includes: Step S01, Radio Frequency Conduction: Fix the sensor 204 around the conductive post 406, and the radio frequency power supply 201 inputs power P to the conductive post 406 through the symmetrical radio frequency interface 402. n (n=1→N,N≥10); Step S02, Signal Processing: Read the sensor output PCB_V n and PCB_I n The true value is calculated using the following formula: , , where PCB_V n PCB_I represents the raw digital voltage value from the nth measurement. n The original digital value of the current in the nth measurement; Step S03, Parameter Fitting: For (PCB_V) n V cal ) and (PCB_I n ,I cal Linear regression was performed to obtain calibration parameters (a1, b1) (voltage) and (a2, b2) (current). Where (PCB_V) n V cal (PCB_I) represents voltage calibration data pairs. n ,I cal ) represents the current calibration data pair; a1 and a2 are linear scaling factors used to correct sensor gain errors; b1 and b2 are zero-point offset factors used to compensate for sensor zero-point drift.

[0040] The technical advantages of the above solution are as follows: high-precision calibration is achieved based on the impedance matching principle, without the need for external commercial sensors; low cost, no need for external calibration components, simple structure, single device handles multiple channels, strong anti-interference, and shielded grounding; in particular, it breaks through the power limitation, supports >15kW, and is suitable for high-voltage power devices, such as 50Hz power devices and semiconductor equipment, such as 13.56MHz semiconductor equipment; multi-channel parallel processing reduces calibration time; full-band algorithm library ensures accuracy; nonlinear fitting unit handles complex relationships, with accuracy superior to linear methods.

[0041] Example 5 like Figure 8 As shown, this embodiment provides a method for calibrating an AC signal sensor, applied to an apparatus for calibrating an AC signal sensor, and is an extension of embodiment four: Connect a fixed load 210 with R=50Ω to the output terminal of device 401 to ensure zero reflection in the transmission path; adjust the output power P of RF power supply 201. n To obtain calibration parameters under high power conditions.

[0042] The technical benefits of the above solution are: it breaks through the power limitations of commercial sensors and supports high-power industrial scenarios.

[0043] Example 6 This embodiment provides a method for calibrating an AC signal sensor, applied to an apparatus for calibrating an AC signal sensor, and is an extension of Embodiment 4: Nonlinear fitting: for (PCB_V) n V cal ) and (PCB_I n ,I cal The exponential function V was fitted using the least squares method. cal =a·e b·PCB_V +c, solve for parameters a, b, c; Where PCB_V is the original voltage reading of the sensor, a is the amplitude scaling factor, b is the nonlinear response factor, and c is the offset correction parameter.

[0044] The technical advantages of the above solution are: by fitting nonlinear relationships using the least squares method, it solves the calibration challenges of sensors over a wide power range, such as when switching between high and low power, thereby improving measurement accuracy.

[0045] In summary, this invention provides a low-cost, high-precision device and method for calibrating AC signal sensors. By integrating a radio frequency conduction module, a signal processing module, and a shielded grounding module, and combining innovative calculation formulas and parameter fitting processes, it effectively solves the problems of high cost, weak anti-interference, and power limitation in existing technologies. The device involved in this invention supports full-band (50Hz-30MHz) applications and is suitable for semiconductor equipment such as 13.56MHz etching equipment and power systems such as 50Hz high-voltage transmission. It can also handle complex sensor relationships through a nonlinear calibration module, improving measurement accuracy and calibration efficiency.

[0046] 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 device for calibrating an AC signal sensor, characterized in that, It includes a radio frequency conduction module (10), a signal processing module (20), and a shielded grounding module (30); The radio frequency conduction module (10) is used to establish a radio frequency energy transmission channel with a standard impedance of 50Ω. It includes a conductive post (406), a symmetrical radio frequency interface (402), and an insulating structure (404). The radio frequency power supply is connected to the top of the conductive post through the symmetrical radio frequency interface, and the bottom of the conductive post is connected to a fixed load (210). The insulating structure isolates the conductive post from the outer shell. The signal processing module (20) is used to calculate the actual current and voltage values ​​based on the power value. The signal processing module (20) includes a microcontroller unit (410) and a communication interface (409). The shielding grounding module (30) is used to construct an electromagnetic shielding environment. It includes an aluminum alloy shell (408) and an elastic conductive clamp (407). The shell completely encloses the radio frequency conduction module and is connected to the ground through a grounding terminal. The elastic conductive clamp fixes the sensor and is in communication with the shell.

2. The apparatus for calibrating an AC signal sensor according to claim 1, characterized in that, The microcontroller unit (410) processes the PCB_V and PCB_I signals output by the AC signal sensor based on a formula, and outputs calibration parameters. The formula is: and Where P is the radio frequency power. V rms R is the effective value of the RF voltage, R is the impedance of the fixed load (210), and I is the effective value of the RF voltage. rms This is the effective value of the radio frequency current.

3. The apparatus for calibrating an AC signal sensor according to claim 1, characterized in that, The symmetrical radio frequency interface (402) is an HN type, N type, LC type or SQS type interface.

4. The apparatus for calibrating an AC signal sensor according to claim 1, characterized in that, It also includes a frequency adaptation module (40), which is used to adapt to the full frequency band of 50Hz-30MHz. The frequency adaptation module (40) includes replaceable conductive pillars and a multi-band algorithm library; wherein replaceable conductive pillars with a diameter ≥30mm are used for the low frequency band of 50Hz-100kHz, and replaceable conductive pillars with a diameter of 5-10mm are used for the high frequency band of 1-30MHz. The multi-band algorithm library is integrated into the microcontroller unit (410).

5. The apparatus for calibrating an AC signal sensor according to claim 1, characterized in that, It also includes a nonlinear calibration module (50) for processing nonlinear sensor calibration; the nonlinear calibration module (50) includes a segmented power controller and a quadratic function fitting unit. The segmented power controller is connected to the RF power supply and adjusts the output power. The exponential function fitting unit is integrated into the microcontroller unit and processes the PCB_V / I signal through the microcontroller unit to realize nonlinear calibration calculation. Data is collected in low / high power segments during the calibration process.

6. The apparatus for calibrating an AC signal sensor according to claim 1 or 2, characterized in that, The microcontroller unit (410) performs parameter fitting through linear regression to obtain calibration parameters.

7. The apparatus for calibrating an AC signal sensor according to claim 5, characterized in that, The nonlinear calibration module (50) uses the least squares method to solve for parameters a, b, and c to handle nonlinear relationships. The fitting index used is V. cal =a·e b·PCB_V +c; where V cal is the true effective value of the radio frequency voltage after calibration of the AC signal sensor, a is the amplitude scaling factor of the nonlinear calibration, b is the nonlinear response coefficient of the nonlinear calibration, c is the offset correction parameter of the nonlinear calibration, and PCB_V is the original digital voltage output of the AC signal sensor.

8. A method for calibrating an AC signal sensor, applied to the apparatus for calibrating an AC signal sensor as described in any one of claims 1-7, characterized in that, Includes the following steps: Step S01, Radio frequency conduction: Fix the sensor (204) around the conductive post (406), and the radio frequency power supply (201) inputs multiple power values ​​to the conductive post through the symmetrical radio frequency interface (402); Step S02, Signal Processing: Read the PCB_Vn and PCB_In signals output by the sensor, based on the formula... and Calculate the actual current and voltage values, where P is the radio frequency power. V rms R is the effective value of the RF voltage, R is the impedance of the fixed load (210), and I is the effective value of the RF voltage. rms This is the effective value of the radio frequency current; Step S03, Parameter Fitting: For (PCB_V) n V cal ) and (PCB_I n ,I cal The exponential function V was fitted using the least squares method. cal =a·e b·PCB_V +c, solve for parameters a, b, c; where V cal is the true effective value of the radio frequency voltage after calibration of the AC signal sensor, a is the amplitude scaling factor of the nonlinear calibration, b is the nonlinear response coefficient of the nonlinear calibration, c is the offset correction parameter of the nonlinear calibration, and PCB_V is the original digital voltage output of the AC signal sensor.

9. The method for calibrating an AC signal sensor according to claim 8, characterized in that, In step S01, the symmetrical radio frequency interface (402) is an HN type interface, and the radio frequency energy transmission direction can be from top to bottom or from bottom to top; the calculation process in step S02 is executed by the microcontroller unit (410) of the signal processing module (20), and the radio frequency power value P is received through the communication interface (409).

10. The method for calibrating an AC signal sensor according to claim 8, characterized in that, It also includes a frequency adaptation step: replacing the diameter of the conductive post to adapt to the 50Hz-100kHz or 1-30MHz frequency band, and automatically switching the impedance mode through a multi-band algorithm library.

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