Radio frequency voltage sensor and plasma source system

Abstract

The invention discloses a radio frequency voltage sensor and a plasma source system. The radio frequency voltage sensor comprises a signal acquisition module and a signal processing circuit. The signal processing circuit comprises a rectangular wave pulse detection module, a signal conversion module, a peak holding module and an operation output module; the input end of the rectangular wave pulse detection module receives a pulse synchronization signal; the signal conversion module is connected with the output end of the signal acquisition module; the first input end of the peak holding module is connected with the output end of the signal conversion module, and the second input end of the peak holding module is connected with the output end of the rectangular wave pulse detection module; and the operation output module is connected with the output end of the peak holding module. According to the radio frequency voltage sensor and the plasma source system provided by the invention, the peak voltage corresponding to the single-stage pulse can be accurately detected, the peak voltage corresponding to the multi-stage pulse can also be stably detected, the output is prevented from jumping to zero during the pulse closing period, and the stability and practicability of measurement are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of circuit measurement and plasma technology, and in particular, to a radio frequency voltage sensor and a plasma source system. BACKGROUND

[0002] The radio frequency voltage sensor is used for measuring a radio frequency peak voltage parameter, reflecting a voltage of a radio frequency in a circuit to be measured.

[0003] The peak voltage measurement of a multi-stage pulse signal is a core requirement. However, when the existing radio frequency voltage sensor collects a multi-stage pulse signal, the output display will jump with the jump of the pulse (for example, a two-stage pulse sequence: Pulse1=5V, Pulse2=0V), so that the user cannot distinguish whether the change of the display value is a voltage difference of the pulse sequence itself or a problem of abnormal operation of the sensor. SUMMARY

[0004] The present application provides a radio frequency voltage sensor and a plasma source system, which can accurately detect the peak voltage corresponding to a single-stage pulse, stably detect the peak voltage corresponding to a multi-stage pulse, and avoid output jumping to zero during the off period of the pulse, thereby improving the stability and practicability of the measurement.

[0005] According to an aspect of the present application, a radio frequency voltage sensor is provided, which comprises a signal collection module and a signal processing circuit.

[0006] The signal processing circuit comprises a rectangular wave pulse detection module, a signal conversion module, a peak holding module and an operation output module.

[0007] The input end of the rectangular wave pulse detection module receives a pulse synchronization signal.

[0008] The output end of the signal conversion module is connected to the output end of the signal collection module.

[0009] The first input end of the peak holding module is connected to the output end of the signal conversion module, and the second input end of the peak holding module is connected to the output end of the rectangular wave pulse detection module.

[0010] The operation output module is connected to the output end of the peak holding module.

[0011] The signal acquisition module is configured to acquire a pulse power signal in a circuit under test; the signal conversion module is configured to convert the pulse power signal into a first voltage signal and output the first voltage signal to a first input end of the peak value holding module; the rectangular wave pulse detection module is configured to output a rectangular wave pulse signal to a second input end of the peak value holding module when the pulse synchronization signal is the rectangular wave pulse signal, and configured to output a constant high level to the second input end of the peak value holding module when the pulse synchronization signal is a continuous high level; the pulse synchronization signal is determined according to the pulse power signal; the peak value holding module is configured to output a current input first voltage signal when the second input end of the peak value holding module is at a high level, and configured to output a first voltage signal corresponding to a last high level when the second input end of the peak value holding module is at a low level; the operation output module is configured to amplify the first voltage signal output by the peak value holding module to generate a second voltage signal and output the second voltage signal.

[0012] Optionally, the signal acquisition module comprises coaxially arranged:

[0013] a probe, a first end of which is electrically connected to the circuit under test;

[0014] a metal column, a second end of the probe being directly electrically connected to the metal column;

[0015] an insulating ring, an outer periphery of the metal column being covered by the insulating ring;

[0016] a metal ring, the insulating ring being covered by the metal ring and being electrically connected to the signal conversion module; wherein the pulse power signal acquired by the probe is capacitively coupled to the metal ring through the metal column.

[0017] Optionally, the rectangular wave pulse detection module comprises:

[0018] a first NAND gate, two input ends of the first NAND gate being electrically connected to each other and receiving the pulse synchronization signal;

[0019] a second NAND gate, two input ends of the second NAND gate being connected in parallel to an output end of the first NAND gate, and an output end of the second NAND gate being electrically connected to the second input end of the peak value holding module.

[0020] Optionally, the rectangular wave pulse detection module is further configured to output a constant high level to the second input end of the peak value holding module when the pulse synchronization signal is a continuous low level.

[0021] The rectangular wave pulse detection module comprises a delay unit, an XOR gate, a first NOT gate and a third NAND gate; wherein the delay unit has an input end receiving a pulse synchronization signal; the XOR gate has a first input end receiving the pulse synchronization signal and a second input end electrically connected with an output end of the delay unit; the first NOT gate has an input end electrically connected with the output end of the delay unit; the third NAND gate has a first input end electrically connected with an output end of the first NOT gate, a second input end electrically connected with an output end of the XOR gate and an output end electrically connected with a second input end of the peak value holding module.

[0022] Optionally, the signal conversion module comprises:

[0023] a voltage reduction unit configured to reduce the pulse power signal output by the metal ring to a third voltage signal;

[0024] a filtering unit configured to filter out high-frequency noise in the third voltage signal to generate a fourth voltage signal;

[0025] a shaping unit configured to shape the fourth voltage signal into a first voltage signal.

[0026] Optionally, the voltage reduction unit comprises a second capacitor and a third capacitor;

[0027] a first end of the second capacitor is electrically connected with the metal ring, and a second end of the second capacitor is electrically connected with a first end of the third capacitor;

[0028] a second end of the third capacitor is grounded;

[0029] the filtering unit comprises a fourth resistor, a fifth resistor, a fourth capacitor, a sixth resistor, a first inductor, a seventh resistor, a fifth capacitor and a sixth capacitor;

[0030] a first end of the fourth resistor is electrically connected with the first end of the third capacitor, and a second end of the fourth resistor is grounded;

[0031] a first end of the fifth resistor is electrically connected with the first end of the fourth resistor, and a second end of the fifth resistor is electrically connected with a first end of the fourth capacitor;

[0032] a second end of the fourth capacitor is electrically connected with a first end of the sixth resistor;

[0033] a second end of the sixth resistor is electrically connected with a first end of the first inductor;

[0034] a second end of the first inductor is grounded;

[0035] a first end of the seventh resistor is electrically connected with the first end of the first inductor, and a second end of the seventh resistor is electrically connected with a first end of the fifth capacitor;

[0036] The second end of the fifth capacitor is grounded.

[0037] The first end of the sixth capacitor is electrically connected with the second end of the fifth capacitor, and the second end of the sixth capacitor is electrically connected with the second power supply end.

[0038] The shaping unit comprises a second diode, a third diode, a fourth diode, an eighth resistor, a seventh capacitor, a ninth resistor and an eighth capacitor.

[0039] The anode of the second diode is electrically connected with the second power supply end, and the cathode of the second diode is electrically connected with the anode of the third diode.

[0040] The anode of the third diode is electrically connected with the first end of the fifth capacitor, and the cathode of the third diode is electrically connected with the first end of the seventh capacitor.

[0041] The first end of the seventh capacitor is electrically connected with the third power supply end, and the second end of the seventh capacitor is grounded.

[0042] The cathode of the fourth diode is electrically connected with the cathode of the second diode, and the anode of the fourth diode is electrically connected with the first end of the eighth resistor.

[0043] The second end of the eighth resistor is grounded.

[0044] The first end of the eighth capacitor is electrically connected with the first end of the eighth resistor, and the second end of the eighth capacitor is grounded.

[0045] The first end of the ninth resistor is electrically connected with the first end of the eighth resistor, and the second end of the ninth resistor is electrically connected with the first input end of the peak holding module.

[0046] Optionally, the operation output module comprises:

[0047] A first operation amplifier unit, whose non-inverting input end receives the output signal of the peak holding module, whose inverting input end is grounded, and whose output end outputs the amplified sixth voltage signal;

[0048] A second operation amplifier unit, whose inverting input end is connected with the output end of the first operation amplifier unit, and whose output end outputs the second voltage signal superimposed with bias.

[0049] Optionally, the second end of the probe is provided with external threads, the metal column is provided with matching internal threads, and the second end of the probe is threadedly connected with the metal column.

[0050] Optionally, the material of the insulating ring comprises polytetrafluoroethylene, polyperfluoroethylene propylene, ethylene tetrafluoroethylene copolymer, ceramic or nylon.

[0051] The material of the probe includes at least one of copper, aluminum, tantalum and silver.

[0052] The material of the metal column includes at least one of copper, aluminum, tantalum and silver.

[0053] The material of the metal ring includes at least one of copper, aluminum, tantalum and silver.

[0054] According to another aspect of the present application, there is provided a plasma source system, comprising a radio frequency power supply module, an impedance matching module, a plasma generator and a radio frequency voltage sensor according to any of the embodiments of the present application.

[0055] The radio frequency voltage sensor is connected between the impedance matching module and the plasma generator, and is configured to monitor the pulse power signal and the pulse synchronization signal output by the radio frequency power supply module in real time.

[0056] The radio frequency voltage sensor according to the embodiments of the present application receives a pulse synchronization signal corresponding to a pulse power signal. When the pulse power signal is not 0 and the pulse power signal is 0 in a cycle of the radio frequency voltage output by the circuit under test, the pulse synchronization signal is a rectangular wave pulse signal. The first input end of the peak holding module in the radio frequency voltage sensor receives a first voltage signal corresponding to the pulse synchronization signal. When the second input end of the peak holding module inputs a high level, the peak holding module outputs the first voltage signal currently input. When the second input end of the peak holding module receives a low level, the output of the peak holding module maintains the first voltage signal corresponding to the previous high level. It can be seen that the second voltage signal output by the radio frequency voltage sensor according to the embodiments of the present application will not jump with the jump of the pulse when collecting multi-stage pulse signals. When the pulse power signal is not 0 in a cycle of the radio frequency voltage output by the circuit under test, the level signal received by the second input end of the peak holding module is always high, so that the operation output module can continuously output a second level signal which is not 0. In summary, the radio frequency voltage sensor according to the embodiments of the present application can accurately detect the peak voltage corresponding to a single-stage pulse, and can stably detect the peak voltage corresponding to multi-stage pulse, and avoid output jump to zero during pulse off, thereby improving the stability and practicability of measurement.

[0057] It should be understood that the matters described in this section are not intended to identify key or essential features of the embodiments of the present application, nor are they used to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0058] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0059] Figure 1 is a structural schematic diagram of a radio frequency voltage sensor according to an embodiment of the present application;

[0060] Figure 2 is a timing sequence diagram of a pulse synchronization signal and a pulse power signal according to an embodiment of the present application;

[0061] Figure 3 is a timing sequence diagram of a pulse synchronization signal and a pulse power signal according to another embodiment of the present application;

[0062] Figure 4 is a timing sequence diagram of a pulse synchronization signal, a pulse power signal and a second voltage signal according to an embodiment of the present application;

[0063] Figure 5 is a structural schematic diagram of a signal acquisition module according to an embodiment of the present application;

[0064] Figure 6 is a circuit structural schematic diagram of a radio frequency voltage sensor according to an embodiment of the present application;

[0065] Figure 7 is a circuit structural schematic diagram of a radio frequency voltage sensor according to another embodiment of the present application;

[0066] Figure 8 is a timing sequence diagram of a plurality of signals according to an embodiment of the present application;

[0067] Figure 9 is a circuit structural schematic diagram of a radio frequency voltage sensor according to another embodiment of the present application;

[0068] Figure 10 is a timing sequence diagram of a plurality of signals according to another embodiment of the present application;

[0069] Figure 11 is a circuit structural schematic diagram of a radio frequency voltage sensor according to another embodiment of the present application;

[0070] Figure 12 is a structural schematic diagram of a plasma source system according to an embodiment of the present application;

[0071] Wherein, 110 - signal acquisition module, 120 - signal processing circuit, 121 - rectangular wave pulse detection module, 122 - signal conversion module, 123 - peak holding module, 124 - operation output module, 111 - probe, 112 - metal column, 113 - insulating ring, 114 - metal ring, 115 - shell, 132 - voltage reduction unit, 133 - filter unit, 134 - shaping unit, 1231 - peak holding unit, 1241 - resistance adjustment unit, 1211 - delay unit, 1213 - differential circuit, 100 - radio frequency voltage sensor, 200 - radio frequency power module, 300 - impedance matching module, 400 - plasma generator. DETAILED DESCRIPTION

[0072] In order to make the personnel in the technical field better understand the present application scheme, the technical scheme in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without creative labor should belong to the scope of protection of the present application.

[0073] It should be noted that the terms "first", "second" and the like in the specification and claims of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0074] Figure 1 It is a structural schematic diagram of a radio frequency voltage sensor according to the embodiments of the present application, referring to Figure 1The radio frequency voltage sensor provided by the embodiment comprises a signal acquisition module 110 and a signal processing circuit 120; the signal processing circuit 120 comprises a rectangular wave pulse detection module 121, a signal conversion module 122, a peak value holding module 123 and an operation output module 124. The input end of the rectangular wave pulse detection module 121 receives a pulse synchronization signal S1; the signal conversion module 122 is connected to the output end of the signal acquisition module 110; the first input end of the peak value holding module 123 is connected to the output end of the signal conversion module 122, and the second input end of the peak value holding module 123 is connected to the output end of the rectangular wave pulse detection module 121; the operation output module 124 is connected to the output end of the peak value holding module 123; wherein: the signal acquisition module 110 is used for acquiring a pulse power signal S2 in a circuit to be measured; the signal conversion module 122 converts the pulse power signal S2 into a first voltage signal and outputs the first voltage signal to the first input end of the peak value holding module 123; the rectangular wave pulse detection module 121 is used for outputting a rectangular wave pulse signal to the second input end of the peak value holding module 123 when the pulse synchronization signal S1 is the rectangular wave pulse signal, and is also used for outputting a constant high level to the second input end of the peak value holding module 123 when the pulse synchronization signal S1 is a continuous high level; wherein, the pulse synchronization signal S1 is determined according to the pulse power signal S2; the peak value holding module 123 is used for outputting the current input first voltage signal when the second input end thereof is at a high level, and is also used for outputting the first voltage signal corresponding to the last high level when the second input end thereof is at a low level; the operation output module 124 amplifies the first voltage signal output by the peak value holding module 123, generates a second voltage signal and outputs the second voltage signal.

[0075] Specifically, the radio frequency voltage sensor provided by the embodiment can be used for acquiring a pulse power signal S2 in a plasma source system. The pulse power signal S2 is an alternating current signal, and the first voltage signal and the second voltage signal S3 are direct current signals. The operation output module 124 in the radio frequency voltage sensor provided by the embodiment can be electrically connected with a display module, and the display module can display the value corresponding to the second voltage signal S3. The second voltage signal S3 can be a peak voltage corresponding to the pulse power signal S2.

[0076] The pulse synchronization signal S1 can be one of a continuous high level and a rectangular wave pulse signal. The pulse synchronization signal S1 and the pulse power signal S2 can be generated simultaneously by a radio frequency power module, and the pulse synchronization signal S1 is determined according to the pulse power signal S2. When the pulse power signal S2 is not 0, the pulse synchronization signal S1 corresponds to a high level, and when the pulse power signal S2 is 0, the pulse synchronization signal S1 corresponds to a low level. When the pulse power signal S2 in a period of the output pulse power signal S2 of the circuit to be measured comprises the pulse power signal S2 which is not 0 and the pulse power signal S2 which is 0, the pulse synchronization signal S1 corresponds to the rectangular wave pulse signal, and the pulse synchronization signal S1 corresponds to the continuous high level when the pulse power signal S2 is 0. Figure 2is a timing sequence diagram of a pulse synchronization signal and a pulse power signal according to an embodiment of the present application, referring to Figure 2 The pulse power signal S2 has a certain duty cycle, and the corresponding pulse synchronization signal S1 is a rectangular wave pulse signal. From time t1 to time t2, the pulse power signal S2 outputs a sine wave type radio frequency power signal, and the rectangular wave pulse signal is at high level to correspond to pulse output. From time t2 to time t3, there is no radio frequency power signal, and the rectangular wave pulse signal is at low level to correspond to pulse off.

[0077] When the pulse power signal S2 in a cycle of the output pulse power signal S2 of the circuit under test only includes the pulse power signal S2 that is not 0, the pulse synchronization signal S1 can be continuously at high level. Exemplarily, Figure 3 is another timing sequence diagram of a pulse synchronization signal and a pulse power signal according to an embodiment of the present application, referring to Figure 3 When the pulse power signal S2 is a continuous sine wave type radio frequency power signal, that is, the pulse power signal S2 is continuously output, in this case, the pulse synchronization signal S1 can be continuously at high level. When the circuit under test continuously has the pulse power signal S2, the second input end of the peak value holding module 123 is always at high level, in this case, the peak value holding module 123 outputs the first voltage signal that the first input end of the peak value holding module 123 is currently inputting.

[0078] When the circuit under test does not output the pulse power signal S2, the second input end of the peak value holding module 123 is at low level, at this time, in order to avoid that the second voltage signal is 0, the embodiment sets that the peak value holding module 123 outputs the first voltage signal corresponding to the last time when the second input end of the peak value holding module 123 inputs high level when the second input end of the peak value holding module 123 is at low level. Exemplarily, Figure 4 is a timing sequence diagram of a pulse synchronization signal, a pulse power signal and a second voltage signal according to an embodiment of the present application, referring to Figure 4 When the pulse power signal S2 in a cycle of the output pulse power signal S2 of the circuit under test includes the pulse power signal S2 that is not 0 and the pulse power signal S2 that is 0, the pulse synchronization signal S1 corresponds to a rectangular wave pulse signal, and the second voltage signal S3 outputs the peak value of the pulse power signal S2 in a cycle of the pulse power signal S2.

[0079] The embodiment provides a radio frequency voltage sensor, which receives a pulse synchronization signal corresponding to a pulse power signal. When the pulse power signal is not 0 and 0 in a cycle of an output radio frequency voltage of a to-be-measured circuit, the pulse synchronization signal is a rectangular wave pulse signal. A first input end of a peak holding module in the radio frequency voltage sensor receives a first voltage signal corresponding to the pulse synchronization signal, the peak holding module outputs the first voltage signal currently input when a high level is input at a second input end of the peak holding module, and the peak holding module maintains the first voltage signal corresponding to a previous high level when a low level is received at the second input end of the peak holding module. It can be seen that the radio frequency voltage sensor provided in the embodiment can prevent the second voltage signal output from jumping when a plurality of pulse signals are collected. When the pulse power signal is not 0 in the cycle of the output radio frequency voltage of the to-be-measured circuit, the level signal received at the second input end of the peak holding module is always high, so that the operation output module can continuously output the second level signal that is not 0. In summary, the radio frequency voltage sensor provided in the embodiment can accurately detect the peak voltage corresponding to a single pulse and stably detect the peak voltage corresponding to a plurality of pulses, and can prevent the output from jumping to zero during the pulse-off period, thereby improving the stability and practicability of measurement.

[0080] Optionally, Figure 5 is a structural schematic diagram of a signal acquisition module according to the embodiment of the application, referring to Figure 5 The signal acquisition module 110 includes coaxially arranged: a probe 111, a metal column 112, an insulating ring 113 and a metal ring 114; the first end of the probe 111 is electrically connected with a to-be-measured circuit; the metal column 112 is directly electrically connected with the second end of the probe 111; the insulating ring 113 covers the outer periphery of the metal column 112; the metal ring 114 covers the insulating ring 113 and is electrically connected with a signal conversion module 122; wherein the pulse power signal collected by the probe 111 is capacitively coupled to the metal ring 114 through the metal column 112.

[0081] Specifically, the signal acquisition module 110 can further include a shell 115, and the shell 115 can cover the outer surface of the metal ring 114. The metal ring 114 can be in the shape of a hollow cylinder. The metal column 112, the insulating ring 113 and the metal ring 114 can be an equivalent capacitor. The probe 111 transmits the collected pulse power signal to the metal column 112, and the pulse power signal is transmitted to the signal conversion module 122 after being coupled to the metal ring 114 through the metal column 112. After passing through the metal column 112, the insulating ring 113 and the metal ring 114, the pulse power signal is converted into a pulse power signal with a small voltage. The equivalent capacitor can reduce the voltage in the pulse power signal in the to-be-measured circuit.

[0082] The equivalent capacitor formed by the metal column 112, the insulating ring 113 and the metal ring 114 has strong voltage resistance performance, can bear high pulse power signals, and the radio frequency voltage sensor is not easily damaged after the pulse power signal is suddenly changed, thereby improving the reliability of the radio frequency voltage sensor.

[0083] Optionally, continuing to refer to Figure 5 The material of the insulating ring 113 includes polytetrafluoroethylene, polytetrafluoroethylene-propylene, ethylene tetrafluoroethylene copolymer, ceramic or nylon; the material of the probe 111 includes at least one of copper, aluminum, tantalum and silver; the material of the metal column 112 includes at least one of copper, aluminum, tantalum and silver; and the material of the metal ring 114 includes at least one of copper, aluminum, tantalum and silver.

[0084] Specifically, the polytetrafluoroethylene, polytetrafluoroethylene-propylene, ethylene tetrafluoroethylene copolymer, ceramic and nylon have high reliability, high temperature resistance, low temperature resistance and high voltage pulse breakdown resistance.

[0085] The material of the probe 111 and the material of the metal ring 114 are at least one of copper, aluminum, tantalum and silver, so that the conductivity of the probe 111 is improved and the radio frequency impedance is reduced. The material of the probe 111 can be the same as the material of the metal ring 114.

[0086] Optionally, continuing to refer to Figure 5 The second end of the probe 111 is provided with external threads, the metal column 112 is provided with matching internal threads, and the second end of the probe 111 is threadedly connected with the metal column 112.

[0087] Specifically, the probe 111 is detachably connected with the metal column 112, so that the probe 111 can be replaced individually.

[0088] Optionally, Figure 6 is a circuit structure schematic diagram of a radio frequency voltage sensor according to an embodiment of the application, referring to Figure 6 and Figure 1 The rectangular wave pulse detection module 121 includes a first NAND gate U1 and a second NAND gate U2, two input ends of the first NAND gate U1 are electrically connected with each other and receive a pulse synchronization signal S1, two input ends of the second NAND gate U2 are connected in parallel to an output end of the first NAND gate U1, and an output end of the second NAND gate U2 is electrically connected with a second input end of the peak value holding module 123.

[0089] Specifically, the first NAND gate U1 and the second NAND gate U2 are connected in the embodiment, so that when the input is a rectangular wave pulse signal, the output is a rectangular wave pulse signal, when the input is a continuous high level, the output is a constant high level, and the noise in the pulse synchronization signal S1 can be removed.

[0090] Optionally, the rectangular wave pulse detection module 121 is further configured to output a constant high level to the second input terminal of the peak holding module 123 when the pulse synchronization signal S1 is at a continuous low level.

[0091] Figure 7 This is a circuit diagram of another RF voltage sensor provided according to an embodiment of the present invention, referring to Figure 7 and Figure 1 , the rectangular wave pulse detection module 121 includes:

[0092] The delay unit 1211 receives the pulse synchronization signal S1 at its input terminal;

[0093] An XOR gate U4, whose first input terminal receives the pulse synchronization signal S1, and whose second input terminal is electrically connected to the output terminal of the delay unit 1211;

[0094] A first NOT gate U3, whose input terminal is electrically connected to the output terminal of the delay unit 1211;

[0095] The third NAND gate U6 has a first input terminal electrically connected to the output terminal of the first NOT gate U3 , a second input terminal electrically connected to the output terminal of the XOR gate U4 , and an output terminal electrically connected to the second input terminal of the peak holding module 123 .

[0096] Specifically, the delay unit 1211 is used to delay the pulse synchronization signal S1. The delay unit 1211 can delay the pulse synchronization signal S1 by half a cycle of the pulse synchronization signal S1. For example, when the duty cycle of the high level in the pulse synchronization signal S1 is 50%, the delay unit 1211 is used to delay the pulse synchronization signal S1 by half a cycle. Figure 8 is a schematic diagram of the timing relationship of multiple signals provided according to an embodiment of the present invention, with reference to Figure 8 When the duty cycle of the high level in pulse synchronization signal S1 is 50%, delay unit 1211 is used to delay the entire pulse synchronization signal S1 by half a cycle to obtain a first delayed signal S4 (the signal outputted by the output terminal of delay unit 1211 is the first delayed signal S4). At this time, rectangular wave pulse detection module 121 outputs pulse synchronization signal S1 to the second input terminal of peak hold module 123. When pulse synchronization signal S1 is continuously high or continuously low, rectangular wave pulse detection module 121 outputs a constant high level to the second input terminal of peak hold module 123.

[0097] Figure 9 This is a circuit diagram of another RF voltage sensor provided according to an embodiment of the present invention, referring to Figure 9 , the rectangular wave pulse detection module 121 includes:

[0098] The delay unit 1211 receives the pulse synchronization signal S1 at its input terminal;

[0099] The first input end of the EXCLUSIVE-OR gate U5 receives the pulse synchronization signal S1, and the second input end is electrically connected with the output end of the delay unit 1211;

[0100] The input end of the second NOT gate U7 is electrically connected with the output end of the EXCLUSIVE-OR gate U5;

[0101] The input end of the first NOT gate U3 is electrically connected with the output end of the delay unit 1211;

[0102] The first input end of the third NAND gate U6 is electrically connected with the output end of the second NOT gate U7, the second input end is electrically connected with the output end of the first NOT gate U3, and the output end is electrically connected with the second input end of the peak value holding module 123.

[0103] Specifically, the delay unit 1211 delays the pulse synchronization signal S1 by one period of the pulse synchronization signal S1. For example, Figure 10 Another timing relationship diagram of multiple signals is provided according to an embodiment of the present application, which is described with reference to Figure 10 The delay unit 1211 delays the pulse synchronization signal S1 by one period, and the signal output at the output end of the delay unit 1211 is recorded as a second delay signal S5. In this way, the rectangular wave pulse detection module 121 can output the rectangular wave pulse signal to the second input end of the peak value holding module 123 when the pulse synchronization signal S1 is a rectangular wave pulse signal, and can also output a constant high level to the second input end of the peak value holding module 123 when the pulse synchronization signal S1 is a continuous high level.

[0104] Optionally, continuing to refer to Figure 6 、 Figure 7 or Figure 9 The signal conversion module includes a voltage reduction unit 132, a filter unit 133 and a shaping unit 134. The voltage reduction unit 132 is used to reduce the pulse power signal S2 output by the metal ring 114 to a third voltage signal. The filter unit 133 is used to filter out high-frequency noise in the third voltage signal to generate a fourth voltage signal. The shaping unit 134 is used to shape the fourth voltage signal into a first voltage signal.

[0105] Specifically, the shaping unit 134 transmits the output first voltage signal to the input end of the operation output module.

[0106] The pulse power signal collected from the to-be-tested circuit is reduced in voltage by the equivalent capacitor formed by the metal column 112, the insulating ring 113 and the metal ring 114, and then reduced in voltage again by the voltage reduction unit 132, so as to avoid damage to the filter unit 133 caused by high-voltage signals.

[0107] The fourth voltage signal is free of noise, so that the fourth voltage signal is better shaped by the shaping unit 134. The shaped first voltage signal can correspond to a peak value of the pulse power signal when the pulse power signal is not 0.

[0108] Optionally, Figure 11 is another circuit structure schematic diagram of a radio frequency voltage sensor according to an embodiment of the present application. Referring to Figure 11 The rectangular wave pulse detection module 121 includes a differential circuit 1213, a first diode D1, a third NOT gate U8, a first resistor R1, and a fourth NAND gate U9. The first end of the differential circuit 1213 is electrically connected to the first end of the first resistor R1. The second end of the differential circuit 1213 is electrically connected to the anode of the first diode D1. The cathode of the first diode D1 is electrically connected to the second end of the first resistor R1. The second end of the first resistor R1 is electrically connected to the first input end of the fourth NAND gate U9. The first end of the third NOT gate U8 is electrically connected to the first end of the differential circuit 1213. The second end of the third NOT gate U8 is electrically connected to the second input end of the fourth NAND gate U9. The output end of the fourth NAND gate U9 is electrically connected to the second input end of the peak value holding module.

[0109] Specifically, the differential circuit 1213 includes a resistor and a capacitor. The differential circuit 1213 is configured to convert a rectangular wave pulse signal into a sharp pulse wave when the pulse synchronization signal S1 is the rectangular wave pulse signal. The differential circuit 1213 is also configured to block the continuous high level and the continuous low level when the pulse synchronization signal S1 is the continuous high level or the continuous low level. The high level only passes through the first diode D1 after the sharp pulse wave. The first end of the differential circuit 1213 is configured to receive the pulse synchronization signal S1. The rectangular wave pulse detection module 121 provided in this embodiment can output the rectangular wave pulse signal to the second input end of the peak value holding module 123 when the pulse synchronization signal S1 is the rectangular wave pulse signal. The rectangular wave pulse detection module 121 can also output the constant high level to the second input end of the peak value holding module 123 when the pulse synchronization signal S1 is the continuous high level or the continuous low level.

[0110] Optionally, continuing to refer to Figure 6 、 Figure 7 or Figure 9The voltage reduction unit 132 includes a second capacitor C2 and a third capacitor C3; a first end of the second capacitor C2 is electrically connected with the metal ring 114, and a second end of the second capacitor C2 is electrically connected with a first end of the third capacitor C3; a second end of the third capacitor C3 is grounded; the filter unit 133 includes a fourth resistor R4, a fifth resistor R5, a fourth capacitor C4, a sixth resistor R6, a first inductor L1, a seventh resistor R7, a fifth capacitor C5 and a sixth capacitor C6; a first end of the fourth resistor R4 is electrically connected with the first end of the third capacitor C3, and a second end of the fourth resistor R4 is grounded; a first end of the fifth resistor R5 is electrically connected with the first end of the fourth resistor R4, and a second end of the fifth resistor R5 is electrically connected with a first end of the fourth capacitor C4; a second end of the fourth capacitor C4 is electrically connected with a first end of the sixth resistor R6; a second end of the sixth resistor R6 is electrically connected with a first end of the first inductor L1; a second end of the first inductor L1 is grounded; a first end of the seventh resistor R7 is electrically connected with the first end of the first inductor L1, and a second end of the seventh resistor R7 is electrically connected with a first end of the fifth capacitor C5; a second end of the fifth capacitor C5 is grounded; a first end of the sixth capacitor C6 is electrically connected with the second end of the fifth capacitor C5, and a second end of the sixth capacitor C6 is electrically connected with the second power supply end VCC2; the shaping unit 134 includes a second diode D2, a third diode D3, a fourth diode D4, an eighth resistor R8, a seventh capacitor C7, a ninth resistor R9 and an eighth capacitor C8; an anode of the second diode D2 is electrically connected with the second power supply end VCC2, and a cathode of the second diode D2 is electrically connected with an anode of the third diode D3; the anode of the third diode D3 is electrically connected with the first end of the fifth capacitor C5, and a cathode of the third diode D3 is electrically connected with a first end of the seventh capacitor C7; the first end of the seventh capacitor C7 is electrically connected with the third power supply end VCC3, and a second end of the seventh capacitor C7 is grounded; a cathode of the fourth diode D4 is electrically connected with the cathode of the second diode D2, and an anode of the fourth diode D4 is electrically connected with a first end of the eighth resistor R8; a second end of the eighth resistor R8 is grounded; a first end of the eighth capacitor C8 is electrically connected with the first end of the eighth resistor R8, and a second end of the eighth capacitor C8 is grounded; a first end of the ninth resistor R9 is electrically connected with the first end of the eighth resistor R8, and a second end of the ninth resistor R9 is electrically connected with the first input end of the peak value holding module 123.

[0111] Optionally, with reference to Figure 6 , Figure 7 or Figure 9 , the operation output module includes: a first operation amplifier unit, a non-inverting input end of the first operation amplifier unit receives an output signal of the peak value holding module 123, an inverting input end of the first operation amplifier unit is grounded, and an output end of the first operation amplifier unit outputs an amplified sixth voltage signal; a second operation amplifier unit, an inverting input end of the second operation amplifier unit is connected with the output end of the first operation amplifier unit, and an output end Vout of the second operation amplifier unit outputs a second voltage signal.

[0112] Specifically, the first operational amplification unit comprises a first operational amplifier, a tenth resistor R10, an eleventh resistor R11, a ninth capacitor C9, a fifth diode D5, and a twelfth resistor R12.

[0113] The second operational amplification unit comprises a thirteenth resistor R13, a fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, a tenth capacitor C10, an eleventh capacitor C11, a twelfth capacitor C12, a thirteenth capacitor C13, a fourteenth capacitor C14, a fifteenth capacitor C15, a second operational amplifier, an adjustable resistor RT, a voltage stabilizing diode DZ, and a resistor adjustment unit 1241.

[0114] The non-inverting input terminal of the first operational amplifier is electrically connected to the output terminal of the peak value holding module 123, the inverting input terminal of the first operational amplifier is electrically connected to the first terminal of the tenth resistor R10, and the output terminal of the first operational amplifier is electrically connected to the first terminal of the twelfth resistor R12. The second terminal of the tenth resistor R10 is grounded; the first terminal of the eleventh resistor R11 is electrically connected to the first terminal of the tenth resistor R10, and the second terminal of the eleventh resistor R11 is electrically connected to the first terminal of the twelfth resistor R12; the first terminal of the ninth capacitor C9 is electrically connected to the first terminal of the tenth resistor R10, the second terminal of the ninth capacitor C9 is electrically connected to the first terminal of the twelfth resistor R12, the anode of the fifth diode D5 is electrically connected to the first terminal of the tenth resistor R10, and the cathode of the fifth diode D5 is electrically connected to the first terminal of the twelfth resistor R12. The second terminal of the twelfth resistor R12 is electrically connected to the inverting input terminal of the second operational amplifier.

[0115] The non-inverting input terminal of the second operational amplifier is electrically connected to the first terminal of the tenth capacitor C10, and the second terminal of the tenth capacitor C10 is grounded; the first terminal of the fourteenth resistor R14 is electrically connected to the first terminal of the tenth capacitor C10 and the first terminal of the fifteenth resistor R15, and the second terminal of the fourteenth resistor R14 is electrically connected to the second terminal of the fifteenth resistor R15 and the second terminal of the tenth capacitor C10.

[0116] The first voltage input end of the second operational amplifier is electrically connected with the second power supply end VCC2, the second voltage input end of the second operational amplifier is electrically connected with the third power supply end VCC3, the first end of the eleventh capacitor C11 is electrically connected with the first voltage input end, and the second end of the eleventh capacitor C11 is grounded; the first end of the twelfth capacitor C12 is electrically connected with the second voltage input end, and the second end of the twelfth capacitor C12 is grounded. The output end of the second operational amplifier is electrically connected with the first end of the thirteenth capacitor C13, and the second end of the thirteenth capacitor C13 is electrically connected with the second end of the twelfth resistor R12. The cathode of the voltage stabilizing diode DZ is electrically connected with the third power supply end VCC3, the anode of the voltage stabilizing diode DZ is electrically connected with the input end of the resistance adjusting unit 1241, the output end of the resistance adjusting unit 1241 is electrically connected with the first power supply end VCC1, the first end of the fourteenth capacitor C14 and the adjustable end of the adjustable resistor RT; the second end of the fourteenth capacitor C14 is grounded. The first end of the adjustable resistor RT is electrically connected with the first end of the sixteenth resistor R16, the second end of the sixteenth resistor R16 is electrically connected with the first end of the fourteenth resistor R14, the second end of the adjustable resistor RT is electrically connected with the first end of the thirteenth resistor R13, and the second end of the thirteenth resistor R13 is electrically connected with the second end of the thirteenth capacitor C13; the first end of the thirteenth capacitor C13 is electrically connected with the first end of the seventeenth resistor R17, the second end of the seventeenth resistor R17 is electrically connected with the first end of the fifteenth capacitor C15, and the second end of the fifteenth capacitor C15 is grounded. The first end of the fifteenth capacitor C15 is the output end Vout of the radio frequency voltage sensor.

[0117] The peak holding module 123 includes a peak holding unit 1231, an eighteenth capacitor C18, a seventeenth capacitor C17 and a sixteenth capacitor C16. The first input end of the peak holding unit 1231 is the first input end of the peak holding module, and the second input end of the peak holding unit 1231 is the second input end of the peak holding module.

[0118] Figure 12 is a structural schematic diagram of a plasma source system provided by an embodiment of the application, referring to Figure 12 The plasma source system provided by the embodiment includes a radio frequency power supply module 200, an impedance matching module 300, a plasma generator 400 and a radio frequency voltage sensor 100 provided by any embodiment of the application; wherein the radio frequency voltage sensor 100 is connected between the impedance matching module 300 and the plasma generator 400, and the radio frequency voltage sensor 100 is used for monitoring the pulse power signal and the pulse synchronization signal output by the radio frequency power supply module 200 in real time.

[0119] Specifically, the impedance matching module 300 is connected between the radio frequency power supply module 200 and the plasma generator 400. The radio frequency power supply module 200 is configured to provide radio frequency energy to the plasma generator 400 to ionize process gas to generate plasma. The impedance matching module 300 is configured to achieve impedance matching between the radio frequency power supply module 200 and the plasma generator 400. The impedance matching module 300 can include a fixed capacitor and a fixed inductor connected in series, or a fixed inductor and an adjustable capacitor connected in series, etc.

[0120] The plasma source system provided by the embodiment includes the radio frequency voltage sensor 100 provided by any of the embodiments of the application, and thus has the beneficial effects of the radio frequency voltage sensor 100 provided by any of the embodiments of the application, which will not be repeated here.

[0121] Optionally, the remote plasma source system provided by the embodiment further includes a directional coupling module and a control module; the control module is electrically connected with the directional coupling module and the radio frequency power supply module; the directional coupling module is configured to detect the reflected power in the plasma source system; and the control module is configured to adjust the output frequency of the radio frequency power supply module according to the reflected power.

[0122] Specifically, the directional coupling module can be electrically connected between the radio frequency power supply module and the impedance matching module. The directional coupling module can send the detected reflected power to the control module. The reflected power can represent the impedance matching between the radio frequency power supply module and the plasma generator. A larger reflected power indicates that the impedance matching between the radio frequency power supply module and the plasma generator does not meet the set requirements.

[0123] The control module can determine the impedance matching between the radio frequency power supply module and the plasma generator according to the reflected power, and adjust the output power of the radio frequency power supply module when the reflected power is large, so as to reduce the reflected power and improve the impedance matching between the radio frequency power supply module and the plasma generator.

[0124] It should be understood that the various forms of flow shown above can be reordered, added to, or deleted from. For example, the steps described in the present application can be executed in parallel, in sequence, or in different orders, as long as the desired results of the technical solutions of the present application can be achieved, and the present application is not limited herein.

[0125] The above detailed description does not constitute a limitation on the scope of protection of the present application. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A radio frequency voltage sensor, characterized in that: include: Signal acquisition module and signal processing circuit; The signal processing circuit includes a rectangular wave pulse detection module, a signal conversion module, a peak holding module and an operation output module; The input end of the rectangular wave pulse detection module receives a pulse synchronization signal; The signal conversion module is connected to the output end of the signal acquisition module; The first input end of the peak holding module is connected to the output end of the signal conversion module, and the second input end of the peak holding module is connected to the output end of the rectangular wave pulse detection module; The operation output module is connected to the output end of the peak holding module; Wherein: the signal acquisition module is used to collect the pulse power signal in the circuit to be tested; the signal conversion module converts the pulse power signal into a first voltage signal and outputs it to the first input end of the peak holding module; the rectangular wave pulse detection module is used to output the rectangular wave pulse signal to the second input end of the peak holding module when the pulse synchronization signal is a rectangular wave pulse signal, and is also used to output a constant high level to the second input end of the peak holding module when the pulse synchronization signal is a continuous high level; wherein, the pulse synchronization signal is determined according to the pulse power signal; the peak holding module is used to output the currently input first voltage signal when its second input end is a high level, and the peak holding module is also used to output the first voltage signal corresponding to the most recent high level when its second input end is a low level; the operation output module amplifies the first voltage signal output by the peak holding module, generates a second voltage signal and outputs it.

2. The radio frequency voltage sensor according to claim 1, characterized in that: The signal acquisition module includes a coaxial arrangement of: a probe, a first end of which is electrically connected to the circuit to be tested; a metal post, directly electrically connected to the second end of the probe; an insulating ring, covering the outer circumference of the metal column; A metal ring covers the insulating ring and is electrically connected to the signal conversion module; wherein the pulse power signal collected by the probe is capacitively coupled to the metal ring via the metal column.

3. The radio frequency voltage sensor according to claim 1, wherein: The rectangular wave pulse detection module includes: a first NAND gate, two input terminals of which are electrically connected to each other and receive the pulse synchronization signal; The second NAND gate has two input terminals connected in parallel to the output terminal of the first NAND gate, and an output terminal electrically connected to the second input terminal of the peak holding module.

4. The radio frequency voltage sensor according to claim 1, wherein: The rectangular wave pulse detection module is further configured to output a constant high level to the second input terminal of the peak hold module when the pulse synchronization signal is at a continuous low level; The rectangular wave pulse detection module includes: a delay unit, an XOR gate, a first NOT gate and a third NAND gate; wherein, the delay unit, its input end receives a pulse synchronization signal; the XOR gate, its first input end receives the pulse synchronization signal, and its second input end is electrically connected to the output end of the delay unit; the first NOT gate, its input end is electrically connected to the output end of the delay unit; the third NAND gate, its first input end is electrically connected to the output end of the first NOT gate, its second input end is electrically connected to the output end of the XOR gate, and its output end is electrically connected to the second input end of the peak hold module.

5. The radio frequency voltage sensor according to claim 2, characterized in that: The signal conversion module includes: a step-down unit, which steps down the pulse power signal output by the metal ring into a third voltage signal; a filtering unit, configured to filter out high-frequency noise in the third voltage signal and generate a fourth voltage signal; A shaping unit shapes the fourth voltage signal into a first voltage signal.

6. The radio frequency voltage sensor according to claim 5, characterized in that: The step-down unit includes a second capacitor and a third capacitor; A first end of the second capacitor is electrically connected to the metal ring, and a second end of the second capacitor is electrically connected to a first end of the third capacitor; The second end of the third capacitor is grounded; The filtering unit includes a fourth resistor, a fifth resistor, a fourth capacitor, a sixth resistor, a first inductor, a seventh resistor, a fifth capacitor and a sixth capacitor; A first end of the fourth resistor is electrically connected to the first end of the third capacitor, and a second end of the fourth resistor is grounded; A first end of the fifth resistor is electrically connected to a first end of the fourth resistor, and a second end of the fifth resistor is electrically connected to a first end of the fourth capacitor; The second end of the fourth capacitor is electrically connected to the first end of the sixth resistor; The second end of the sixth resistor is electrically connected to the first end of the first inductor; The second end of the first inductor is grounded; A first end of the seventh resistor is electrically connected to a first end of the first inductor, and a second end of the seventh resistor is electrically connected to a first end of the fifth capacitor; The second end of the fifth capacitor is grounded; The first end of the sixth capacitor is electrically connected to the second end of the fifth capacitor, and the second end of the sixth capacitor is electrically connected to the second power supply end; The shaping unit includes a second diode, a third diode, a fourth diode, an eighth resistor, a seventh capacitor, a ninth resistor and an eighth capacitor; The anode of the second diode is electrically connected to the second power supply terminal, and the cathode of the second diode is electrically connected to the anode of the third diode; An anode of the third diode is electrically connected to the first end of the fifth capacitor, and a cathode of the third diode is electrically connected to the first end of the seventh capacitor; A first end of the seventh capacitor is electrically connected to the third power supply terminal, and a second end of the seventh capacitor is grounded; The cathode of the fourth diode is electrically connected to the cathode of the second diode, and the anode of the fourth diode is electrically connected to the first end of the eighth resistor; The second end of the eighth resistor is grounded; A first end of the eighth capacitor is electrically connected to the first end of the eighth resistor, and a second end of the eighth capacitor is grounded; The first end of the ninth resistor is electrically connected to the first end of the eighth resistor, and the second end of the ninth resistor is electrically connected to the first input end of the peak holding module.

7. The radio frequency voltage sensor according to claim 1, characterized in that: The operation output module includes: a first operational amplifier unit, having a non-inverting input terminal receiving the output signal of the peak hold module, an inverting input terminal being grounded, and an output terminal outputting the amplified sixth voltage signal; The second operational amplifier unit has an inverting input terminal connected to the output terminal of the first operational amplifier unit, and an output terminal outputting a second voltage signal superimposed with a bias.

8. The radio frequency voltage sensor according to claim 2, characterized in that: The second end of the probe is provided with an external thread, the metal column is provided with a matching internal thread, and the second end of the probe is threadedly connected to the metal column.

9. The radio frequency voltage sensor according to claim 2, characterized in that: The material of the insulating ring includes polytetrafluoroethylene, polytetrafluoroethylene, ethylene tetrafluoroethylene copolymer, ceramic or nylon; The material of the probe includes at least one of copper, aluminum, tantalum and silver; The material of the metal pillar includes at least one of copper, aluminum, tantalum and silver; The material of the metal ring includes at least one of copper, aluminum, tantalum and silver.

10. A plasma source system, characterized in that: It comprises a radio frequency power supply module, an impedance matching module, a plasma generator and the radio frequency voltage sensor according to any one of claims 1 to 9; The RF voltage sensor is connected between the impedance matching module and the plasma generator, and is used to monitor the pulse power signal and the pulse synchronization signal output by the RF power module in real time.

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