Impedance matcher, radio frequency power supply system and plasma source system

Abstract

The invention discloses an impedance matcher, a radio frequency power supply system and a plasma source system. The impedance matcher comprises an impedance matching module, a control module and a plurality of adjustable capacitor modules which are connected in parallel, the first end of each adjustable capacitor module is electrically connected with the first end of the impedance matching module, and the second end of each adjustable capacitor module is grounded; each adjustable capacitor module comprises an adjustable capacitor unit and a switch unit which are connected in series; the control module is used for controlling the switch unit in the at least one adjustable capacitor module to be switched on and controlling the switch unit in the at least one adjustable capacitor module to be switched off when the load is in the current impedance; and the capacitance value of the adjustable capacitor unit in the adjustable capacitor module where the at least one disconnected switch unit is located is adjusted according to the next impedance of the load. According to the invention, impedance matching between the radio frequency power supply module and the load can be realized while the impedance of the load is changed, and impedance matching can be quickly realized.

Description

Technical Field

[0001] The present invention relates to the field of radio frequency technology, and particularly to an impedance matcher, a radio frequency power supply system, and a plasma source system. Background Art

[0002] Currently, with the development of radio frequency power supply technology, the requirement for impedance matching between a radio frequency power supply module and a load is also getting higher and higher.

[0003] An impedance matcher is usually installed between a radio frequency power supply module and a load. Currently, the common method is to adjust the capacitance value of a tunable capacitor in the impedance matcher to perform impedance matching between the radio frequency power supply module and the load.

[0004] However, the current impedance matcher has a problem that the adjustment speed of the capacitance value is slow after the impedance of the load changes, resulting in a long impedance matching time between the radio frequency power supply module and the load. Summary of the Invention

[0005] The present invention provides an impedance matcher, a radio frequency power supply system, and a plasma source system, which can achieve impedance matching between a radio frequency power supply module and a load while the impedance of the load changes, and can quickly achieve impedance matching.

[0006] According to an aspect of the present invention, an impedance matcher is provided. The impedance matcher includes: an impedance matching module, a control module, and a plurality of tunable capacitor modules connected in parallel; A first end of the impedance matching module is electrically connected to an output end of a radio frequency power supply module, and a second end of the impedance matching module is electrically connected to an input end of a load; A first end of each of the tunable capacitor modules is electrically connected to the first end of the impedance matching module, and a second end of each of the tunable capacitor modules is grounded; each of the tunable capacitor modules includes a tunable capacitor unit and a switch unit connected in series; The control module is configured to, when the load is at a current impedance, control the switch unit in at least one of the tunable capacitor modules to conduct, and at the same time control the switch unit in at least one of the tunable capacitor modules to disconnect, and adjust the capacitance value of the tunable capacitor unit in the tunable capacitor module where at least one of the disconnected switch units is located according to the next impedance of the load, so that the total capacitance value formed by the tunable capacitor units with the adjusted capacitance value matches the next impedance of the load, and is further configured to, when the impedance of the load changes from the current impedance to the next impedance, control the currently conducting switch unit to disconnect and at the same time control the switch unit in the tunable capacitor module where the tunable capacitor unit with the adjusted capacitance value is located to conduct.

[0007] Optionally, the plurality of tunable capacitor modules connected in parallel includes two tunable capacitor modules connected in parallel; The control module is configured to, when the load is at the current impedance, control the switch unit in one of the adjustable capacitor modules to conduct, and at the same time control the switch unit in the other adjustable capacitor module to disconnect, and adjust the capacitance value of the adjustable capacitor unit in the adjustable capacitor module where the disconnected switch unit is located according to the next impedance of the load, so that the capacitance value of the adjusted adjustable capacitor unit matches the next impedance. The control module is further configured to, when the impedance of the load changes from the current impedance to the next impedance, control the currently conducting switch unit to disconnect and control the currently disconnected switch unit to conduct.

[0008] Optionally, the multiple adjustable capacitor modules connected in parallel include adjustable capacitor modules equal in number to the number of impedances of the load; Each impedance of the load corresponds to one of the adjustable capacitor modules; The control module is configured to, before each impedance of the load is formed, adjust the capacitance value of the adjustable capacitor unit in the adjustable capacitor module corresponding to each impedance of the load, so that the capacitance value of each adjusted adjustable capacitor unit matches the impedance of the load corresponding thereto.

[0009] Optionally, the switch unit includes a switch control sub-unit and a diode; The control end of the switch control sub-unit is electrically connected to the control module, and the output end of the switch control sub-unit is electrically connected to the anode of the diode; The anode of the diode is electrically connected to the first end of the adjustable capacitor unit, and the cathode of the diode is grounded; The second end of the adjustable capacitor unit is electrically connected to the first end of the impedance matching module; The control module is configured to control the diode to conduct or disconnect through the switch control sub-unit.

[0010] Optionally, the switch control sub-unit includes a first resistor, a first transistor, a second resistor, a second transistor, a third resistor, a first capacitor, a first inductor, a second inductor, a second capacitor, a fourth resistor, and a fifth resistor; The first end of the first resistor is electrically connected to the control module, and the second end of the first resistor is grounded; The gate of the first transistor is electrically connected to the first end of the first resistor, the first pole of the first transistor is grounded, and the second pole of the first transistor is electrically connected to the first end of the second resistor; The second end of the second resistor is electrically connected to the gate of the second transistor; The first pole of the second transistor is electrically connected to the first power supply terminal, and the second pole of the second transistor is electrically connected to the first end of the third resistor; The second end of the third resistor is electrically connected to the first end of the first capacitor; The first end of the first capacitor is electrically connected to the first end of the first inductor, and the second end of the first capacitor is grounded; The second end of the first inductor is electrically connected to the first end of the second inductor; The first end of the second inductor is electrically connected to the anode of the diode, and the second end of the second inductor is electrically connected to the first end of the second capacitor; The first end of the second capacitor is electrically connected to the first end of the fourth resistor, and the second end of the second capacitor is grounded; The second end of the fourth resistor is electrically connected to the second power supply terminal; The first end of the fifth resistor is electrically connected to the first power supply terminal, and the second end of the fifth resistor is electrically connected to the second end of the second resistor.

[0011] Optionally, the impedance matcher provided in this embodiment further includes a detection module; the detection module includes an amplitude detection unit and a phase detection unit; The amplitude detection unit is used to detect the voltage amplitude and current amplitude output by the radio frequency power supply module; The phase detection unit is used to detect the voltage phase and current phase output by the radio frequency power supply module; The control module is used to adjust the output frequency of the radio frequency power supply module according to the voltage amplitude, the current amplitude, the voltage phase, and the current phase.

[0012] Optionally, the impedance matcher provided in this embodiment further includes a directional coupling module and an alarm module; The directional coupling module is used to detect the reverse power and forward power between the radio frequency power supply module and the load; The control module is used to adjust the output frequency of the radio frequency power supply module according to the reverse power, and is further used to control the alarm module to send an alarm signal when the forward power is less than the set power.

[0013] Optionally, the impedance matching module includes at least one fixed inductor and at least one fixed capacitor; The fixed inductor and the fixed capacitor are connected in series; The adjustable capacitor unit includes at least one adjustable capacitor.

[0014] According to another aspect of the present invention, a radio frequency power supply system is provided, and the radio frequency power supply system includes a radio frequency power supply module and the impedance matcher provided in any embodiment of the present invention.

[0015] According to another aspect of the present invention, there is provided a plasma source system, which includes a reaction chamber and the RF power supply system provided by any embodiment of the present invention.

[0016] An embodiment of the present invention provides an impedance matcher, which is connected between an RF power supply module and a load. When the load is at the current impedance, a control module in the impedance matcher adjusts the capacitance value of a tunable capacitor unit in a tunable capacitor module where a partially disconnected switch unit is located according to the next impedance of the load to obtain a total capacitance value. And when the impedance of the load changes from the current impedance to the next impedance, it controls the sum of the capacitance values of the working tunable capacitor modules in the impedance matcher to be the total capacitance value, where the total capacitance value matches the next impedance, so as to ensure that the impedance of the RF power supply module matches the impedance of the load while the impedance of the load changes. When the load is a reaction chamber, the type of gas, the flow rate of gas, the pressure of gas, and the power of the pulse output by the RF power supply module in the reaction chamber will all cause changes in the impedance of the load. The control module in the embodiment of the present invention can obtain in advance the value of the impedance in the load and the moment of impedance change. It can be seen that the impedance matcher provided by the embodiment of the present invention can be applied to an RF power supply module that outputs multi-stage pulses, and can also ensure that the impedance of the load matches the impedance of the RF power supply module in time when the type of gas, the flow rate of gas, and the pressure of gas in the reaction chamber change. The impedance matcher provided by the embodiment of the present invention can adjust the total capacitance value corresponding to the load where impedance change occurs before the impedance of the load changes, so as to achieve matching by controlling the conduction of the switch unit while the impedance of the load changes, without having to repeatedly adjust the capacitance value according to the changed impedance after the impedance of the load changes. It can be seen that the impedance matcher provided by the embodiment of the present invention can basically achieve impedance matching between the RF power supply module and the load while the impedance of the load changes, and can quickly achieve impedance matching.

[0017] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0019] Figure 1 is a schematic structural diagram of an impedance matcher related to the technology of the present invention; Figure 2 It is a schematic structural diagram when an impedance matcher is electrically connected to a radio frequency power supply module and a load according to an embodiment of the present invention; Figure 3 It is another schematic structural diagram when an impedance matcher is electrically connected to a radio frequency power supply module and a load according to an embodiment of the present invention; Figure 4 It is another schematic structural diagram when an impedance matcher is electrically connected to a radio frequency power supply module and a load according to an embodiment of the present invention; Figure 5 It is another schematic structural diagram when an impedance matcher is electrically connected to a radio frequency power supply module and a load according to an embodiment of the present invention; Figure 6 It is another schematic structural diagram when an impedance matcher is electrically connected to a radio frequency power supply module and a load according to an embodiment of the present invention; Figure 7 It is a schematic structural diagram of a radio frequency power supply system according to an embodiment of the present invention. Detailed implementation manners

[0020] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0021] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above drawings are used to distinguish similar objects, and do not necessarily need to describe a specific order or sequence. It should be understood that such used data can be interchanged under appropriate circumstances so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" 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 clearly listed steps or units, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0022] Figure 1 It is a schematic structural diagram of an impedance matcher related to the technology of the present invention, refer to Figure 1, the impedance matcher is connected between the RF power supply module and the load. The impedance matcher includes a control module, a first adjustable capacitor CL1, and a second adjustable capacitor CT1. When the impedance of the load changes, the control module adjusts the capacitance values of the first adjustable capacitor CL1 and the second adjustable capacitor CT1 according to the changed impedance to ensure impedance matching between the RF power supply module and the load. However, the adjustment speed of the capacitance value is too slow, resulting in a high matching delay and unable to achieve impedance matching quickly.

[0023] To solve the above problem of impedance matching delay, an embodiment of the present invention provides an impedance matcher that can achieve impedance matching between the RF power supply module and the load while the impedance of the load changes.

[0024] Figure 2 It is a schematic structural diagram when an impedance matcher provided by an embodiment of the present invention is electrically connected to an RF power supply module and a load. Refer to Figure 2 , the impedance matcher provided in this embodiment includes: an impedance matching module 110, a control module 120, and a plurality of adjustable capacitor modules 130 connected in parallel; a first end of the impedance matching module 110 is electrically connected to an output end of the RF power supply module 200, and a second end of the impedance matching module 110 is electrically connected to an input end of the load 300; a first end of each adjustable capacitor module 130 is electrically connected to the first end of the impedance matching module 110, and a second end of each adjustable capacitor module 130 is grounded; each adjustable capacitor module 130 includes an adjustable capacitor unit 131 and a switch unit 132 connected in series; the control module 120 is configured to, when the load 300 is at the current impedance, control the switch unit 132 in at least one adjustable capacitor module 130 to conduct, and at the same time control the switch unit 132 in at least one adjustable capacitor module 130 to disconnect, and adjust the capacitance value of the adjustable capacitor unit 131 in the adjustable capacitor module 130 where at least one disconnected switch unit 132 is located according to the next impedance of the load 300, so that the total capacitance value formed by the adjustable capacitor units 131 with adjusted capacitance values matches the next impedance of the load 300, and is further configured to, when the impedance of the load 300 changes from the current impedance to the next impedance, control the currently conducting switch unit 132 to disconnect and at the same time control the switch unit 132 in the adjustable capacitor module 130 where the adjustable capacitor unit 131 with adjusted capacitance value is located to conduct.

[0025] Specifically, the number of adjustable capacitor modules 130 in the impedance matcher 100 provided in this embodiment can be 2, 3, 4, 5, etc. The switch unit 132 and the adjustable capacitor unit 131 in the same adjustable capacitor module 130 are connected in series. The specific connection method can be that the switch unit 132 is connected between the first end of the impedance matching module 110 and the first end of the adjustable capacitor unit 131, and the second end of the adjustable capacitor unit 131 is grounded. It can also be that the adjustable capacitor unit 131 is connected between the first end of the impedance matching module 110 and the first end of the switch unit 132, and the second end of the switch unit 132 is grounded.

[0026] The capacitance value of the adjustable capacitor unit 131 connected in series with the conducting switch unit 132 affects the impedance matching between the load 300 and the RF power supply module 200. The capacitance value of the adjustable capacitor unit 131 connected in series with the disconnected switch unit 132 does not affect the impedance matching between the load 300 and the RF power supply module 200. The impedance matching module 110 and the adjustable capacitor module 130 where the conducting switch unit 132 is located in this embodiment work together to enable impedance matching between the RF power supply module 200 and the load 300. The impedance matching module 110 can include a fixed inductor, or can include a fixed inductor and a fixed capacitor connected in series, or can also include a fixed inductor and an adjustable capacitor connected in series, etc.

[0027] The control module 120 is electrically connected to the control end of each adjustable capacitor unit 131, and the control module 120 can adjust the capacitance value of each adjustable capacitor unit 131. The control module 120 is electrically connected to the control end of each switch unit 132, and the control module 120 can control each switch unit 132 to conduct or disconnect. When the load 300 is at the current impedance, the control module 120 can control the switch unit 132 in one adjustable capacitor module 130 to conduct, and at the same time control the switch unit 132 in at least one adjustable capacitor module 130 to disconnect, or can control the switch units 132 in two or more adjustable capacitor modules 130 to conduct, and at the same time control the switch unit 132 in at least one adjustable capacitor module 130 to disconnect. The switch unit 132 can be a triode, or can also include a switch control sub-unit and a diode.

[0028] The total capacitance value is the total capacitance value formed after the control module 120 adjusts the capacitance value of the adjustable capacitance unit 131 in the adjustable capacitance module 130 where the switched-off switch unit 132 is located when the load 300 is at the current impedance. Exemplarily, when the load 300 is at the current impedance, if the control module 120 adjusts the capacitance value of the adjustable capacitance unit 131 in one switched-off switch unit 132 in the adjustable capacitance module 130, the capacitance value of this adjusted adjustable capacitance unit 131 is the total capacitance value. When the load 300 is at the current impedance, if the control module 120 adjusts the capacitance values of the adjustable capacitance units 131 in two switched-off switch units 132 in the adjustable capacitance module 130, the capacitance value after the parallel connection of these two adjusted adjustable capacitance units 131 is the total capacitance value. The matching of the total capacitance value with the next impedance of the load 300 means that when the impedance of the load 300 is the next impedance, the total capacitance value and the matching value corresponding to the impedance matching module 110 can make the impedance of the RF power supply module 200 match the impedance of the load 300. Different impedances of the load 300 correspond to different total capacitance values. The control module 120 is also used to store the total capacitance values corresponding to the impedances of different loads 300. The control module 120 is used to determine the total capacitance value corresponding to the next impedance according to the next impedance when obtaining the next impedance of the load 300, and adjust the capacitance value of the adjustable capacitance unit 131 in the adjustable capacitance module 130 where the switched-off switch unit 132 is located to adjust to the total capacitance value.

[0029] The current impedance of the load 300 is the impedance of the load 300 at the current stage, and the next impedance of the load 300 refers to the impedance of the load 300 at the next stage. The current impedance and the next impedance are not equal. The next impedance of the load 300 is adjacent to the current impedance of the load 300 and is generated after the current impedance. Different powers of the pulses output by the RF power supply module 200 will result in different impedances of the load 300. When the load 300 is a reaction chamber capable of generating plasma, the impedance of the reaction chamber (i.e., the impedance of the load 300) is related to the type of gas input into the reaction chamber, the gas pressure (which can also be understood as the pressure of the reaction chamber), and the gas flow rate. When at least one of the type of gas, the gas pressure, and the gas flow rate in the reaction chamber changes, the impedance of the reaction chamber will change. When the power of the pulses output by the RF power supply module 200 changes can be set in advance, when the type of gas, the gas pressure, and the gas flow rate input into the load 300 change can all be set in advance. Therefore, when the impedance of the load 300 can change and what the impedance is after the change can both be set in advance. The control module 120 can also store the impedances of the load 300 at different time periods.

[0030] The control module 120 can also determine the impedance of the load 300 and the time when the impedance changes by obtaining the power of the pulse output by the radio frequency power supply module 200 and the time when the pulse power changes, the air pressure of the gas input into the load 300 and the time when the air pressure changes, the flow rate of the gas input into the load 300 and the time when the flow rate changes, and the type of the gas input into the load 300 and the time when the type changes.

[0031] The total capacitance value corresponding to the power of each pulse, each air pressure of the gas, each flow rate of the gas, and each type of the gas can be obtained through experiments in advance. When the load 300 is at the current impedance, the control module 120 can determine the next impedance of the load 300 and the total capacitance value corresponding to the next impedance by obtaining the power of the pulse output by the radio frequency power supply module 200 in the next stage, the type, flow rate, and air pressure of the gas input into the load 300 in the next stage, and adjust the capacitance value of the adjustable capacitance unit 131 in the adjustable capacitance module 130 where at least one disconnected switch unit 132 is located to obtain the corresponding total capacitance value. Thus, when the impedance of the load 300 changes from the current impedance to the next impedance, the switch unit 132 of the adjustable capacitance module 130 where the adjustable capacitance unit 131 with the adjusted capacitance value is located is turned on, so that the capacitance value of the working adjustable capacitance module 130 in the impedance matcher 100 is the total capacitance value. That is, when the impedance of the load 300 changes to the next impedance, the impedance matcher 100 provided in this embodiment can immediately output the total capacitance value and the matching value corresponding to the impedance matching module 110. It only takes the time for the switch unit 132 to close to achieve the impedance matching between the load 300 and the radio frequency power supply module 200 after the impedance of the load 300 changes, and its matching speed can reach the microsecond level.

[0032] The impedance matcher 100 provided in this embodiment can be applicable to both the radio frequency power supply module 200 that outputs single-stage pulses and the radio frequency power supply module 200 that outputs multi-stage pulses. Exemplarily, when the power of the pulse output by the radio frequency power supply module 200 changes, the impedance of the load 300 will change. The control module 120 in this embodiment can obtain the power of the next pulse output by the radio frequency power supply module 200 when the radio frequency power supply module 200 outputs the current pulse, so as to obtain the next impedance of the load 300, and adjust the capacitance value of the adjustable capacitance unit 131 in the partially adjustable capacitance module 130 where the switch unit 132 is disconnected according to the next impedance to obtain the total capacitance value, and turn on the switch unit 132 of the adjustable capacitance module 130 where the adjustable capacitance unit 131 with the adjusted capacitance value is located when the output pulse of the radio frequency power supply module 200 switches from the current pulse to the next pulse.

[0033] This embodiment provides an impedance matcher, which is connected between a radio frequency power supply module and a load. When the load is at the current impedance, the control module in the impedance matcher adjusts the capacitance value of the adjustable capacitance unit in the adjustable capacitance module where the switch unit with a partially disconnected state is located according to the next impedance of the load to obtain the total capacitance value. And when the impedance of the load changes from the current impedance to the next impedance, it controls the sum of the capacitance values of the working adjustable capacitance modules in the impedance matcher to be the total capacitance value, where the total capacitance value matches the next impedance, so as to ensure that the impedance matcher realizes the impedance matching between the radio frequency power supply module and the load while the impedance of the load changes. When the load is a reaction chamber, the type of gas, the flow rate of the gas, the pressure of the gas, and the power of the pulse output by the radio frequency power supply module in the reaction chamber will all cause changes in the impedance of the load. The control module in this embodiment can obtain in advance the value of the impedance in the load and the moment of impedance change. It can be seen that the impedance matcher provided in this embodiment can be applied to a radio frequency power supply module that outputs multi-stage pulses, and can also ensure the impedance matching between the load and the radio frequency power supply module in a timely manner when the type of gas, the flow rate of the gas, and the pressure of the gas in the reaction chamber change. The impedance matcher provided in this embodiment can adjust the total capacitance value corresponding to the load with impedance change before the impedance of the load changes, so as to achieve matching by controlling the conduction of the switch unit while the impedance of the load changes, without having to adjust the capacitance value multiple times according to the changed impedance after the impedance of the load changes. It can be seen that the impedance matcher provided in this embodiment can basically achieve the impedance matching between the radio frequency power supply module and the load while the impedance of the load changes, and can quickly achieve impedance matching.

[0034] Optionally, Figure 3 is a schematic structural diagram when another impedance matcher provided according to an embodiment of the present invention is electrically connected to a radio frequency power supply module and a load. Refer to Figure 3 , the multiple adjustable capacitance modules 130 connected in parallel include two adjustable capacitance modules 130 connected in parallel; the control module 120 is configured to, when the load 300 is at the current impedance, control the switch unit 132 in one adjustable capacitance module 130 to conduct, and at the same time control the switch unit 132 in the other adjustable capacitance module 130 to disconnect, and adjust the capacitance value of the adjustable capacitance unit 131 in the adjustable capacitance module 130 where the disconnected switch unit 132 is located according to the next impedance of the load 300, so that the capacitance value of the adjusted adjustable capacitance unit 131 matches the next impedance, and is further configured to, when the impedance of the load 300 changes from the current impedance to the next impedance, control the currently conducting switch unit 132 to disconnect and at the same time control the currently disconnected switch unit 132 to conduct.

[0035] Specifically, the capacitance value of the adjusted adjustable capacitance unit 131 matching the next impedance means that when the impedance of the load 300 is the next impedance, the capacitance value of the adjusted adjustable capacitance unit 131 and the corresponding matching value of the impedance matching module 110 can make the impedance of the radio frequency power supply module 200 match the impedance of the load 300.

[0036] In this embodiment, the switch units 132 in the two adjustable capacitance modules 130 are not simultaneously turned on or off. The control module 120 is configured to control one switch unit 132 to be turned on and simultaneously control the other switch unit 132 to be turned off when the load 300 is at the current impedance, and adjust the capacitance value of the adjustable capacitance unit 131 in the adjustable capacitance module 130 where the turned-off switch unit 132 is located to the capacitance value corresponding to the next impedance of the load 300 according to the next impedance of the load 300, so as to ensure that when the impedance of the load 300 changes from the current impedance to the next impedance, the impedance of the radio frequency power supply module 200 can be immediately matched with the impedance of the load 300.

[0037] The impedance matcher 100 provided in this embodiment is provided with two adjustable capacitance modules 130, which can not only ensure the impedance matching between the radio frequency power supply module 200 and the load 300 when the impedance of the load 300 changes, but also reduce the number of devices in the impedance matcher 100 and lower the cost of the impedance matcher 100.

[0038] Optionally, continuing to refer to Figure 2 or Figure 3 , the multiple adjustable capacitance modules 130 connected in parallel include the same number of adjustable capacitance modules 130 as the number of impedances of the load 300; each impedance of the load 300 corresponds to one adjustable capacitance module 130; the control module 120 is configured to adjust the capacitance values of the adjustable capacitance units 131 in the adjustable capacitance modules 130 corresponding to the respective impedances of the load 300 before the respective impedances of the load 300 are formed, so that the capacitance values of the adjusted adjustable capacitance units 131 match the corresponding impedances of the load 300.

[0039] Exemplarily, the radio frequency power supply module 200 can output multi-level pulses, and the power of each level of pulse is different. Pulses with the same power are the same pulse. Different pulse powers correspond to the impedances of different loads 300. Each pulse output by the radio frequency power supply module 200 corresponds to the impedance of a load 300, and the impedance of each load 300 corresponds to an adjustable capacitor module 130. It can be seen that each pulse output by the radio frequency power supply module 200 corresponds to an adjustable capacitor module 130. Before each pulse is output, the control module 120 adjusts the capacitance value of the adjustable capacitor unit 131 in the adjustable capacitor module 130 corresponding to the pulse. At the same time as the pulse is switched, the switch unit 132 in the adjustable capacitor module 130 corresponding to the switched pulse is turned on, and the switch unit 132 in the adjustable capacitor module 130 corresponding to the pulse before switching is turned off.

[0040] In the impedance matcher 100 provided in this embodiment, the number of adjustable capacitor modules 130 is the same as the number of impedances of the load 300. When the impedance of the load 300 changes, the switch unit 132 corresponding to the impedance of the load 300 can be directly turned on. By adjusting the capacitance value of the adjustable capacitor unit 131 in the adjustable capacitor module 130 corresponding to each impedance of the load 300, the impedance matching between the radio frequency power supply module 200 and the load 300 can be immediately achieved after the impedance of the load 300 changes.

[0041] Optionally, Figure 4 is a schematic structural diagram when another impedance matcher provided according to an embodiment of the present invention is electrically connected to a radio frequency power supply module and a load. Refer to Figure 4 , the switch unit 132 includes a switch control sub-unit 1321 and a diode 1322; the control end of the switch control sub-unit 1321 is electrically connected to the control module 120, and the output end of the switch control sub-unit 1321 is electrically connected to the anode of the diode 1322; the anode of the diode 1322 is electrically connected to the first end of the adjustable capacitor unit 131, and the cathode of the diode 1322 is grounded; the second end of the adjustable capacitor unit 131 is electrically connected to the first end of the impedance matching module 110; the control module 120 is used to control the diode 1322 to conduct or disconnect through the switch control sub-unit 1321.

[0042] Specifically, in this embodiment, the switch unit 132 is set to be grounded, which is convenient for the switch unit 132 to dissipate heat quickly. In this embodiment, by setting the conduction or disconnection of the control diode 1322, the conduction speed of the switch unit 132 is increased, thereby further increasing the impedance matching speed between the radio frequency power supply module 200 and the load 300. The control module 120 is used to send a control signal to the switch control sub-unit 1321 to control the diode 1322 to conduct or disconnect.

[0043] Optionally, continue to refer to Figure 4, the switch control sub-unit 1321 includes a first resistor R1, a first transistor M1, a second resistor R2, a second transistor M2, a third resistor R3, a first capacitor C1, a first inductor L1, a second inductor L2, a second capacitor C2, a fourth resistor R4, and a fifth resistor R5; a first end of the first resistor R1 is electrically connected to the control module 120, and a second end of the first resistor R1 is grounded; a gate of the first transistor M1 is electrically connected to the first end of the first resistor R1, a first pole of the first transistor M1 is grounded, and a second pole of the first transistor M1 is electrically connected to a first end of the second resistor R2; a second end of the second resistor R2 is electrically connected to a gate of the second transistor M2; a first pole of the second transistor M2 is electrically connected to a first power supply terminal VGH, and a second pole of the second transistor M2 is electrically connected to a first end of the third resistor R3; a second end of the third resistor R3 is electrically connected to a first end of the first capacitor C1; a first end of the first capacitor C1 is electrically connected to a first end of the first inductor L1, and a second end of the first capacitor C1 is grounded; a second end of the first inductor L1 is electrically connected to a first end of the second inductor L2; a first end of the second inductor L2 is electrically connected to an anode of the diode 1322, and a second end of the second inductor L2 is electrically connected to a first end of the second capacitor C2; a first end of the second capacitor C2 is electrically connected to a first end of the fourth resistor R4, and a second end of the second capacitor C2 is grounded; a second end of the fourth resistor R4 is electrically connected to a second power supply terminal VGL; a first end of the fifth resistor R5 is electrically connected to the first power supply terminal VGH, and a second end of the fifth resistor R5 is electrically connected to a second end of the second resistor R2.

[0044] Specifically, the first power supply terminal VGH is used to receive a first power supply voltage, and the second power supply terminal VGL is used to receive a second power supply voltage. The first power supply voltage is positive, and the second power supply voltage is negative. The first transistor M1 can be an NMOS transistor, and the second transistor M2 can be a PMOS transistor. By setting the first resistor R1 to be electrically connected to the first transistor M1, the fifth resistor R5 to be electrically connected to the second transistor M2, and the second resistor R2 to be connected between the second transistor M2 and the first transistor M1, it can be ensured that the first transistor M1 conducts when at a high level when it is an NMOS transistor, and the second transistor M2 conducts when at a low level when it is a PMOS transistor. The fourth resistor R4 and the third resistor R3 are used for current limiting. The first capacitor C1, the first inductor L1, the second capacitor C2, and the second inductor L2 can be used for choke filtering. The control module 120 can send a high level to control the diode 1322 to conduct, and send a low level to control the diode 1322 to turn off.

[0045] Optionally, Figure 5 is a schematic structural diagram when another impedance matcher according to an embodiment of the present invention is electrically connected to a radio frequency power supply module and a load. Refer to Figure 5, the impedance matcher 100 provided in this embodiment further includes a detection module 140; the detection module 140 includes an amplitude detection unit 141 and a phase detection unit 142; the amplitude detection unit 141 is configured to detect the voltage amplitude and current amplitude output by the RF power supply module 200; the phase detection unit 142 is configured to detect the voltage phase and current phase output by the RF power supply module 200; the control module 120 is configured to adjust the output frequency of the RF power supply module 200 according to the voltage amplitude, current amplitude, voltage phase, and current phase.

[0046] Specifically, both the amplitude detection unit 141 and the phase detection unit 142 are electrically connected to the control module 120. The amplitude detection unit 141 is configured to send the detected voltage amplitude and current amplitude to the control module 120, and the phase detection unit 142 is configured to send the detected voltage phase and current phase to the control module 120. The control module 120 can monitor the current impedance matching condition between the RF power supply module 200 and the load 300 according to the voltage amplitude, current amplitude, voltage phase, and current phase, and send a first frequency adjustment signal to the RF power supply module 200 when the impedance matching between the RF power supply module 200 and the load 300 does not meet the set requirements. After receiving the first frequency adjustment signal, the RF power supply module 200 adjusts the output frequency of the RF power supply module 200 so that the adjusted output frequency of the RF power supply module 200 can ensure the impedance matching between the RF power supply module 200 and the load 300 under the current conditions, thereby improving the impedance matching accuracy between the RF power supply module 200 and the load 300.

[0047] Optionally, Figure 6 is a schematic structural diagram when another impedance matcher provided according to an embodiment of the present invention is electrically connected to an RF power supply module and a load. Refer to Figure 6 , the impedance matcher 100 provided in this embodiment further includes a directional coupling module 150 and an alarm module 160; the directional coupling module 150 is configured to detect the reverse power and forward power between the RF power supply module 200 and the load 300; the control module 120 is configured to adjust the output frequency of the RF power supply module 200 according to the reverse power, and is further configured to control the alarm module 160 to send an alarm signal when the forward power is less than the set power.

[0048] Specifically, the directional coupling module 150 can be a directional coupler. The directional coupling module 150 is connected between the RF power supply module 200 and the load 300. The directional coupling module 150 can be electrically connected to the wire that transmits the RF signal output by the RF power supply module 200. The directional coupling module 150 is also electrically connected to the control module 120. The directional coupling module 150 can send the reverse power and forward power to the control module 120. The control module 120 can determine the current impedance matching condition between the RF power supply module 200 and the load 300 according to the reverse power, and send a second frequency adjustment signal to the RF power supply module 200 when the impedance matching between the RF power supply module 200 and the load 300 does not meet the set requirements. After receiving the second frequency adjustment signal, the RF power supply module 200 adjusts the output frequency of the RF power supply module 200 so that the adjusted output frequency of the RF power supply module 200 can ensure the impedance matching between the RF power supply module 200 and the load 300, thereby further improving the impedance matching accuracy between the RF power supply module and the load.

[0049] The forward power can reflect the actual output power situation of the RF power supply module 200. When the control module 120 detects that the forward power is less than the set power, it indicates that the actual power output by the RF power supply module 200 does not meet the requirements of the load 300. At this time, the control module 120 can control the alarm module 160 to send an alarm signal to prompt the staff to check the situation in time.

[0050] Optionally, continue to refer to Figure 6 , the impedance matching module 110 includes at least one fixed inductor LT and at least one fixed capacitor CT; the fixed inductor CT and the fixed capacitor LT are connected in series; the adjustable capacitor unit 131 includes at least one adjustable capacitor CL.

[0051] Specifically, the impedance matching module 110 includes a fixed inductor LT and a fixed capacitor CT connected in series. It can be seen that the impedance matching module 110 provided in this embodiment corresponds to a fixed matching value. In order to ensure the impedance matching between the RF power supply module 200 and the load 300, it is only necessary to adjust the capacitance value of the adjustable capacitor CL in the adjustable capacitor module 130 where the conducting switch unit 132 is located, avoiding increasing the adjustment complexity by adjusting multiple adjustable capacitors CL.

[0052] Figure 7 is a schematic structural diagram of a RF power supply system according to an embodiment of the present invention. Refer to Figure 7 , the RF power supply system 400 provided in this embodiment includes a RF power supply module 200 and the impedance matcher 100 provided in any embodiment of the present invention. Therefore, the beneficial effects of the RF power supply system including the impedance matcher 100 described in any embodiment of the present invention will not be elaborated here.

[0053] The plasma source system provided in this embodiment includes a reaction chamber and the RF power supply system provided in any embodiment of the present invention. Therefore, this plasma source system has the beneficial effects of the impedance matcher described in any embodiment of the present invention, which will not be elaborated herein.

[0054] It should be understood that various forms of the processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in the present invention can be executed in parallel, sequentially, or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and no limitation is imposed herein.

[0055] The above specific embodiments do not constitute a limitation on the protection scope of the present invention. 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 principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An impedance matching device, characterized in that: include: An impedance matching module, a control module, and a plurality of adjustable capacitor modules connected in parallel; The first end of the impedance matching module is electrically connected to the output end of the RF power supply module, and the second end of the impedance matching module is electrically connected to the input end of the load; The first end of each of the adjustable capacitor modules is electrically connected to the first end of the impedance matching module, and the second end of each of the adjustable capacitor modules is grounded; each of the adjustable capacitor modules includes an adjustable capacitor unit and a switch unit connected in series; The control module is used to control at least one switch unit in the adjustable capacitor module to be turned on when the load is in the current impedance, and to control at least one switch unit in the adjustable capacitor module to be turned off, and to adjust the capacitance value of the adjustable capacitor unit in the adjustable capacitor module where at least one disconnected switch unit is located according to the next impedance of the load, so that the total capacitance value formed by the adjustable capacitor unit after the capacitance value is adjusted matches the next impedance of the load, and is also used to control the currently turned-on switch unit to be turned off and to control the switch unit in the adjustable capacitor module where the adjustable capacitor unit whose capacitance value is adjusted is located to be turned on when the impedance of the load changes from the current impedance to the next impedance.

2. The impedance matching box according to claim 1, characterized in that: The plurality of adjustable capacitor modules connected in parallel include two adjustable capacitor modules connected in parallel; The control module is used to control the switch unit in one of the adjustable capacitor modules to be turned on and the switch unit in another adjustable capacitor module to be turned off when the load is in the current impedance, and to adjust the capacitance value of the adjustable capacitor unit in the adjustable capacitor module where the disconnected switch unit is located according to the next impedance of the load so that the capacitance value of the adjusted adjustable capacitor unit matches the next impedance, and is also used to control the currently turned on switch unit to be turned off and the currently disconnected switch unit to be turned on when the impedance of the load changes from the current impedance to the next impedance.

3. The impedance matching box according to claim 1, characterized in that: The plurality of adjustable capacitor modules connected in parallel include adjustable capacitor modules whose number is equal to the impedance of the load; Each impedance of the load corresponds to one of the adjustable capacitor modules; The control module is used to adjust the capacitance value of the adjustable capacitance unit in the adjustable capacitance module corresponding to each impedance of the load before each impedance of the load is formed, so that the capacitance value of each adjustable capacitance unit after adjustment matches the impedance of the corresponding load.

4. The impedance matching box according to claim 1, characterized in that: The switch unit includes a switch control subunit and a diode; The control end of the switch control subunit is electrically connected to the control module, and the output end of the switch control subunit is electrically connected to the anode of the diode; The anode of the diode is electrically connected to the first end of the adjustable capacitor unit, and the cathode of the diode is grounded; The second end of the adjustable capacitor unit is electrically connected to the first end of the impedance matching module; The control module is used to control the diode to be turned on or off through the switch control subunit.

5. The impedance matching box according to claim 4, characterized in that: The switch control subunit includes a first resistor, a first transistor, a second resistor, a second transistor, a third resistor, a first capacitor, a first inductor, a second inductor, a second capacitor, a fourth resistor and a fifth resistor; A first end of the first resistor is electrically connected to the control module, and a second end of the first resistor is grounded; The gate of the first transistor is electrically connected to the first end of the first resistor, the first electrode of the first transistor is grounded, and the second electrode of the first transistor is electrically connected to the first end of the second resistor; The second end of the second resistor is electrically connected to the gate of the second transistor; A first electrode of the second transistor is electrically connected to the first power supply terminal, and a second electrode of the second transistor is electrically connected to a first end of the third resistor; The second end of the third resistor is electrically connected to the first end of the first capacitor; The first end of the first capacitor is electrically connected to the first end of the first inductor, and the second end of the first capacitor is grounded; The second end of the first inductor is electrically connected to the first end of the second inductor; The first end of the second inductor is electrically connected to the anode of the diode, and the second end of the second inductor is electrically connected to the first end of the second capacitor; The first end of the second capacitor is electrically connected to the first end of the fourth resistor, and the second end of the second capacitor is grounded; The second end of the fourth resistor is electrically connected to the second power supply end; A first end of the fifth resistor is electrically connected to the first power supply end, and a second end of the fifth resistor is electrically connected to the second end of the second resistor.

6. The impedance matching box according to claim 1, characterized in that: It also includes a detection module; the detection module includes an amplitude detection unit and a phase detection unit; The amplitude detection unit is used to detect the voltage amplitude and current amplitude output by the RF power module; The phase detection unit is used to detect the voltage phase and current phase output by the RF power module; The control module is used to adjust the output frequency of the radio frequency power module according to the voltage amplitude, the current amplitude, the voltage phase and the current phase.

7. The impedance matching box according to claim 1, characterized in that: It also includes a directional coupling module and an alarm module; The directional coupling module is used to detect the reverse power and forward power between the RF power module and the load; The control module is used to adjust the output frequency of the radio frequency power module according to the reverse power, and is also used to control the alarm module to send an alarm signal when the forward power is less than the set power.

8. The impedance matcher according to any one of claims 1 to 7, characterized in that: The impedance matching module includes at least one fixed inductor and at least one fixed capacitor; The fixed inductor and the fixed capacitor are connected in series; The adjustable capacitor unit includes at least one adjustable capacitor.

9. A radio frequency power supply system, characterized in that: It comprises a radio frequency power supply module and the impedance matcher according to any one of claims 1 to 8.

10. A plasma source system, characterized in that: It comprises a reaction chamber and the radio frequency power supply system as claimed in claim 9.

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