A radio frequency generation system and a plasma generation system for plasma excitation in plasma processing, and a method for exciting plasma in plasma processing.
The described radio frequency generation system addresses power loss issues in plasma generation by generating multiple frequency signals and using adjustable impedance to optimize plasma excitation, enhancing efficiency and control.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- ROHDE & SCHWARZ GMBH & CO KG
- Filing Date
- 2025-09-19
- Publication Date
- 2026-06-10
Smart Images
Figure 2026095322000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a radio frequency generation system for plasma excitation in plasma processing. The present invention also relates to a plasma generation system for plasma excitation in plasma processing. Further, the present invention relates to a method for exciting plasma in plasma processing.
Background Art
[0002] A plasma generation system including a plasma processing chamber and a signal generator for radio frequency plasma applications is disclosed in the prior art. Usually, the signal generator is connected to the plasma processing chamber using a separately designed matching network, also called a match box. The matching network protects the signal generator from mismatches.
[0003] However, a drawback of known solutions in the prior art is that the matching network that works to protect the signal generator from mismatches results in additional power losses and, as a result, reduces the efficiency of the plasma generation system.
Summary of the Invention
[0004] Therefore, an object of the present invention is to increase the efficiency of the plasma generation system.
[0005] According to the present invention, the objective is achieved by a radio frequency generation system for plasma excitation of a plasma process, comprising a signal generation unit configured to generate at least three radio frequency signals having different frequencies. The signal generation unit has a shared signal generation output from which the radio frequency signals are output. The radio frequency generation system comprises a broadband amplification stage connected to the shared signal generation output and configured to amplify the radio frequency signals, and outputs the amplified radio frequency signals at the amplification stage output of the amplification stage. The radio frequency generation system comprises a matching network connected to the amplification stage output of the amplification stage and configured to set a predetermined impedance to the amplification stage output of the amplification stage, wherein the impedance between the amplification stage output and the matching network is not equal to 50 ohms. The radio frequency generation system comprises a plasma process impedance acquisition unit configured to acquire the complex impedance of the plasma process. The radio frequency generation system comprises a control unit connected to the plasma process impedance acquisition unit for signal transmission and configured to control the signal generation unit, amplification stage, and / or matching network based on the acquired complex impedance of the plasma process.
[0006] In addition, according to the present invention, the objective is a method for exciting a plasma for plasma processing, comprising the steps of: generating at least three radio frequency signals having different frequencies using a signal generation unit; outputting the radio frequency signals via a shared signal generation output of the signal generation unit; amplifying the radio frequency signals using a broadband amplification stage; and outputting the amplified radio frequency signals at the amplification stage output of the amplification stage, wherein a predetermined impedance of the amplification stage output of the amplification stage is set using a matching network, the impedance between the amplification stage output and the matching network is not equal to 50 ohms, the complex impedance of the plasma processing is obtained using a plasma processing impedance acquisition unit, and the signal generation unit, amplification stage, and / or matching network are controlled based on the acquired complex impedance of the plasma processing.
[0007] The fundamental idea of this invention is to obtain the complex impedance of a plasma process, particularly in real time, and to use it to control the plasma process, also particularly in real time. To control the plasma process, the components of the radio frequency generation system can be appropriately controlled to provide the radio frequency signal necessary for exciting the plasma process as desired. Since the amplification stage and / or matching network can also be controlled in addition to the signal generation unit, the amplification and / or matching of the radio frequency signal can also be appropriately controlled to increase efficiency.
[0008] For this purpose, the matching network is low-loss and not provided in a 50-ohm environment. For example, the plasma impedance is between 5 ohms and 10 ohms, i.e., less than 50 ohms, and the impedance between the amplification stage output and the matching network can be 2 ohms. Because the matching network is provided between the amplification stage and the downstream plasma chamber where the plasma is excited, the matching network works to protect the upstream amplification stage and the upstream signal generation unit.
[0009] The broadband amplification stage includes at least one radio frequency amplifier, particularly multiple radio frequency amplifiers corresponding to different frequency ranges, in order to implement the broadband amplification stage cost-effectively. The broadband amplification stage includes at least three different frequencies of at least three radio frequency signals generated by the signal generation unit. The use of a broadband amplification stage makes it possible to incorporate multiple fundamental frequencies to generate the complex signal shape of plasma excitations.
[0010] To generate at least three radio frequency signals, the signal generation unit includes at least one signal generator, in particular at least three signal generators. In this view, each radio frequency signal may have its own signal generator assigned to it. When multiple signal generators are given, the output lines from the multiple signal generators are connected to each other, in particular via an adder, using a given shared signal generation output. Alternatively, only one signal generator may be given, and its output signal may be divided and fed to a frequency shifter to obtain at least three radio frequency signals having different frequencies. For example, a frequency divider is given to give at least three radio frequency signals having different frequencies. This means that at least three radio frequency signals have their respective division ratios to each other.
[0011] One embodiment gives a first radio frequency signal having a first frequency, a second radio frequency signal having a second frequency, and a third radio frequency signal having a third frequency, where the third frequency is three times the first frequency and twice the second frequency. In this view, the first and second radio frequency signals each have frequencies that are part of the frequency of the third radio frequency signal. Different frequencies can be realized using a signal generator in which the output signal is divided into three signals, two of which are processed using different frequency dividers, particularly 2:1 and 3:1 frequency dividers. For example, the third radio frequency signal has a third frequency of 40.68 MHz, the first radio frequency signal has a first frequency of 13.56 MHz, i.e., one-third of the third frequency, and the second radio frequency signal has a second frequency of 20.34 MHz, i.e., half of the third frequency.
[0012] A further embodiment provides that the signal generation unit is configured to adjust the frequency of each of at least three radio frequency signals individually and independently of the other radio frequency signals. This is possible in output signals corresponding to radio frequency signals provided via a shared signal generation output, in particular when the signal generation unit includes multiple signal generators that can be controlled individually. Alternatively, a frequency shifter (rather than a dedicated frequency divider) may be provided, which is appropriately controlled to change the frequency of each of the at least three radio frequency signals. Each of the at least three radio frequency signals may have a signal generator or frequency shifter assigned to it, and the frequency of each radio frequency signal may be adjusted individually and independently of the other radio frequency signals.
[0013] For example, a signal generation unit may be configured to individually and independently adjust the amplitude and / or phase of at least three radio frequency signals, apart from other radio frequency signals. This is possible with respect to amplitude and / or phase, in particular when the signal generation unit includes multiple signal generators that can be controlled individually. Alternatively, provisions may be made to provide phase shifters and / or amplifiers or attenuators to the signal paths diverging from the signal generators in order to individually and independently adjust the amplitude and / or phase of the radio frequency signals.
[0014] Generally, the signal generation unit may include a field-programmable gate array (FPGA), i.e., an integrated circuit, and in particular, the signal generation unit is configured to perform direct digital synthesis (DDS) to generate at least three radio frequency signals having different frequencies.
[0015] Furthermore, the matching network may include at least one adjustable capacitor, and the control unit is configured to adjust the capacitance of the adjustable capacitor. A network of capacitors may also be provided that can be connected to adjust the capacitance of the matching network. In this regard, a motor is not required to adjust the capacitance. Alternatively or in addition, the matching network may be given to include adjustable inductors and / or adjustable reactors, i.e., multiple inductors or reactors that can be connected.
[0016] In a further embodiment, the plasma processing impedance acquisition unit includes a directional coupler configured to separate forward and backward waves from each other, and a measurement unit configured to acquire the forward power of the forward wave and the reflected power of the backward wave. The complex impedance of the plasma processing may be acquired using the forward and reflected powers. In this regard, the control unit is configured to control the signal generation unit, amplification stage, and / or matching network based on the acquired forward power of the forward wave and the acquired reflected power of the backward wave. The respective powers, i.e., forward power and reflected power, may be determined for each of the radio frequency signals, and in particular for mixed products of radio frequency signals. Each measurement unit, also called a detector, may be provided for the forward power and reflected power, i.e., the forward and backward waves. For this purpose, the measurement unit is connected to the appropriate ports of the directional coupler, with each of the forward waves and the backward waves coupled by the directional coupler connected to the appropriate measurement unit. The scattering parameters may be determined in particular as complex values representing magnitude and angle, i.e., amplitude and phase. In this regard, amplitude and phase can be measured by their respective measuring units in order to determine the corresponding power in this manner.
[0017] In particular, the plasma processing impedance acquisition unit includes at least one sensor configured to measure voltage, current, and the phase between voltage and current. In addition to the impedance of the plasma processing, current and voltage may be acquired, as well as the phase between voltage and current. At least one sensor may be integrated on a printed circuit board, thereby providing a suitable compact structure.
[0018] The radio frequency generation system may include an input interface configured to receive at least one radio frequency signal from an external signal source, in particular, a bypass provided between the input interface and the amplification stage. The external radio frequency signal can therefore be supplied to the radio frequency generation system, and based thereon, at least three radio frequency signals having different frequencies can be generated. However, it is also possible to provide at least three radio frequency signals having different frequencies via the input interface, which are amplified using a broadband amplification stage. In this case, a bypass is provided between the input interface and the amplification stage and can be switched between the internal signal generation unit and the input interface. In other words, the amplification stage may communicate with either the internal signal generation unit or the input interface to obtain at least three radio frequency signals having different frequencies to be amplified.
[0019] A further embodiment provides that the control unit comprises a control unit interface used to receive control signals. The control signals may be start signals and / or stop signals. Frequency, signal shape, power, amplitude, and / or phase may be specified and controlled using the control signals. The control unit interface may be an Ethernet interface, for example, EtherCAT, or "Ethernet for Control Automation Technology."
[0020] In addition, the signal generation unit may be configured to perform voltage waveform tailoring in order to generate radio frequency signals, i.e., at least three radio frequency signals having different frequencies. Voltage waveform tailoring is also called voltage waveform tailoring. By tailoring the voltage waveform of the radio frequency signals, a more precise influence on the excited plasma can be achieved, and the pulse cycle, pulse shape, or edge shape can be adjusted accordingly.
[0021] The objective is also achieved by an invention of a plasma generation system for plasma excitation for plasma processing, which includes a plasma chamber and a radio frequency generation system as described above. The radio frequency generation system is connected to at least one electrode located in the plasma chamber. The advantages described above also apply to the plasma generation system.
[0022] One embodiment provides that the plasma processing impedance acquisition unit is positioned closer to at least one electrode than the matching network. The plasma processing impedance acquisition unit is therefore directly associated with the plasma chamber in which at least one electrode is located, which is why the impedance of the plasma processing can be acquired. In particular, the plasma processing impedance acquisition unit is provided between the matching network and the plasma chamber.
[0023] In this regard, the plasma processing impedance acquisition unit is provided at the output of the radio frequency generation system, which is used to connect the plasma chamber to the radio frequency generation system. The forward and reflected waves of each wave of the radio frequency signal are therefore acquired at the output of the radio frequency generation system.
[0024] Essentially, accurate real-time acquisition of the complex impedance of plasma processing is effective in close proximity to the plasma chamber, enabling rapid control of RF power in a controlled manner.
[0025] In addition, the use of the broadband amplification stage also enables incorporating multiple fundamental frequencies or parts of the fundamental frequencies to generate a complex signal shape for controlling the plasma, i.e., for so-called "voltage waveform tuning (VWT)".
Brief Description of the Drawings
[0026] Further advantages and features of the present invention will become apparent from the following detailed description and the drawings referred to as follows.
[0027] [Figure 1] FIG. 1 shows a schematic diagram of a plasma generation system according to an invention having a radio frequency generation system according to a first embodiment of the present invention. [Figure 2] FIG. 2 shows a schematic diagram of a plasma generation system according to an invention having a radio frequency generation system according to a second embodiment of the present invention. [Figure 3] FIG. 3 shows an overview of a method according to an invention for exciting the plasma of plasma processing.
Modes for Carrying Out the Invention
[0028] The detailed description set forth below in connection with the appended drawings, which illustrate by way of example and not limitation, shows various embodiments in which the same reference numerals refer to the same elements and is not intended to be limited to the embodiments shown. Each embodiment described in this disclosure is provided by way of example or illustration only and should not be construed as preferred or advantageous over other embodiments. The exemplary examples provided herein are not intended to be exhaustive or to limit the claimed subject matter to the exact forms disclosed.
[0029] For the purposes of this disclosure, the phrase "at least one of A, B, and C" means, for example, (A), (B), (C), (A and B), (A and C), (B and C), or (A, B, and C), including all other possible permutations when three or more elements are listed. In other words, the term "at least one of A and B" generally means "A and / or B," i.e., "A" only, "B" only, or "A and B."
[0030] Figure 1 shows a plasma generation system 10 for plasma excitation in plasma processing, which comprises a radio frequency generation system 12 and a plasma chamber 14 connected to the radio frequency generation system 12 and provided with at least one electrode 16 used to generate plasma.
[0031] The radio frequency generation system 12 generates a radio frequency signal that is passed to the electrode 16 to generate plasma.
[0032] The radio frequency generation system 12 includes a signal generation unit 18 which can generate at least three radio frequency signals having different frequencies, which are output at a shared signal generation output 20.
[0033] In the embodiment shown in Figure 1, the signal generation unit 18 includes a signal generator 22, such as an FPGA.
[0034] The broadband amplification stage 24, connected to the signal generation output 20, receives at least three radio frequency signals having different frequencies from the signal generation unit 18, amplifies them, and as a result, an amplified radio frequency signal is produced and output at the amplification stage output 26 of the amplification stage 24.
[0035] The matching network 28 connected to the amplification stage output 26 of the amplification stage 24 includes at least one adjustable capacitor 30, in particular a network 32 of multiple adjustable capacitors 30, e.g., connectable capacitors. Alternatively or in addition, the matching network 28 may include multiple adjustable inductors and / or reactors that can be connected to adjust the inductance or reactor. Essentially, the matching network 28 sets a predetermined impedance to the amplification stage output 26 of the amplification stage 24, and the impedance between the amplification stage output 26 and the matching network 28 is not equal to 50 ohms.
[0036] In addition, the radio frequency generation system 12 includes a plasma processing impedance acquisition unit 34 located downstream of the matching network 28, and particularly upstream of the output 36 of the radio frequency generation system 12.
[0037] The plasma processing impedance acquisition unit 34 includes a directional coupler 38 and a measurement unit 40 connected to the directional coupler 38. The directional coupler 38 separates the forward and backward waves of the radio frequency signal from each other, which are then supplied to the measurement unit 40 to acquire the forward power of the forward wave and the reflected power of the backward wave. In particular, the amplitude and phase of the forward and backward waves are acquired to draw conclusions about the forward power and reflected power, respectively.
[0038] Based on the acquired parameters, namely forward power and reflected power, the complex impedance of the plasma processing within the plasma chamber 14 can be obtained, which serves as a control parameter for the plasma processing.
[0039] Therefore, the radio frequency generation system 12 further includes a control unit 42 connected to a plasma processing impedance acquisition unit 34 for signal transmission in order to acquire the complex impedance of the acquired plasma processing. Based on this, the control unit 42 can control the signal generation unit 18, the amplification stage 24, and / or the matching network 28.
[0040] To ensure that the impedance of the plasma processing within the plasma chamber 14 is obtained as accurately as possible, the plasma processing impedance acquisition unit 34 is positioned closer to at least one electrode 16 than the matching network 28.
[0041] In addition, the plasma processing impedance acquisition unit 34 acquires the plasma processing voltage U p Plasma treatment current I p , and the voltage U of the plasma treatment p and plasma processing current I p It may include at least one sensor 44 that can be used to detect the phase between and . In this regard, further parameters are obtained to characterize the plasma processing.
[0042] The impedance of the plasma treatment, determined by the forward and reflected power, may be used as a primary parameter for controlling the plasma treatment, having current, voltage, and the phase between voltage and current, which serve as additional parameters for controlling the plasma treatment. In particular, the desired voltage for achieving the plasma treatment can be defined using components of the radio frequency generation system 12 controlled for this purpose, namely the signal generation unit 18, the amplification stage 24, and / or the matching network 28.
[0043] When controlling the signal generation unit 18, the control unit 42 can individually adjust the frequency of each of the at least three radio frequency signals, independently of the other radio frequency signals.
[0044] Similarly, the control unit 42 may control the signal generation unit 18 so that the amplitude and / or phase of each of the at least three radio frequency signals is adjusted individually and independently of the other radio frequency signals.
[0045] With respect to the broadband amplification stage 24, the control unit 42 adapts by appropriately controlling the broadband amplification stage 24 in order to individually adjust the frequency of each of the at least three radio frequency signals, independently of the other radio frequency signals.
[0046] Furthermore, the control unit 42 is adapted to control the matching network 28 such that at least one adjustable capacitor 30 is adjusted or connected. Alternatively, or in addition, at least one adjustable inductor or reactor is adjusted or connected.
[0047] In principle, the radio frequency generation system 12 may also include an input interface 46 that can supply at least a radio frequency signal to the radio frequency generation system 12 from an external signal source.
[0048] The broadband amplification stage 24 is connected to the signal generation unit 18 in the first operating mode and to the input interface in the second operating mode, using a signal transmission method. In other words, the broadband amplification stage 24 is connected to either the signal generation unit 18 or the input interface 46 using a signal transmission method to amplify radio frequency signals generated by the signal generation unit 18 or radio frequency signals received via the input interface 46. The switching unit 48 and the bypass 50 to the signal generation unit 18 are provided for switching to directly connect the broadband amplification stage 24 (second operating mode) to the input interface 46 using a signal transmission method. In this regard, the signal generation unit 18 is appropriately connected by the bypass 50 in the second operating mode.
[0049] The control unit 42 itself includes a control unit interface 52 that receives control signals processed by the control unit 42, for example, to control components of the radio frequency generation system 12, particularly the signal generation unit 18. For example, this allows for adjustment of the voltage waveform to ensure precise effects on the excited plasma.
[0050] The embodiment shown in Figure 2 differs from the first embodiment shown in Figure 1 in the configuration of the signal generation unit 18. In the second embodiment, the signal generation unit 18 includes a plurality of signal generators 22, which are connected to a shared signal generation output 20 using an adder 54.
[0051] In the embodiment shown in Figure 2, the control unit 42 individually controls the frequency, amplitude, and / or phase of the radio frequency signals generated by each of the signal generators 22.
[0052] Basically, the radio frequency generation system 12 can be used to generate a first radio frequency signal having a first frequency (e.g., 13.56 MHz), a second radio frequency signal having a second frequency (e.g., 20.34 MHz), and a third radio frequency signal having a third frequency (e.g., 40.68 MHz). For example, the third frequency is three times the first frequency and twice the second frequency.
[0053] Using the plasma generation system 10 shown in Figures 1 and 2, the method shown in Figure 3 for exciting the plasma for plasma processing can be performed.
[0054] In the first step S1, the signal generation unit 18 generates at least three radio frequency signals having different frequencies.
[0055] In the second step S2, the radio frequency signal is output via the shared signal generation output 20 of the signal generation unit 18.
[0056] In the third step S3, the radio frequency signal is amplified using the broadband amplification stage 24 to obtain an amplified radio frequency signal.
[0057] In the fourth step S4, the amplified radio frequency signal is output at the amplification stage output 26 of the amplification stage 24.
[0058] The amplified radio frequency signal output via the amplification stage output 26 of the amplification stage 24 is passed to the electrode 16 in the plasma chamber 14 to excite the plasma. Here, a specific impedance to the amplification stage output 26 of the amplification stage 24 is set using a matching network 28.
[0059] At the same time, the complex impedance of the plasma treatment is acquired using the plasma treatment impedance acquisition unit 34, which is performed using the directional coupler 38 and the measurement unit 40 to measure the forward power of the forward wave and the reflected power of the backward wave. Based on the forward power of the forward wave and the reflected power of the backward wave, the complex impedance of the plasma treatment is determined.
[0060] The complex impedance of the plasma processing is used as a control parameter, and the control unit 42 therefore controls the signal generation unit 18, the amplification stage 24, and / or the matching network 28 based on the complex impedance of the plasma processing.
[0061] Methods that can be performed using the plasma generation system 10, particularly the radio frequency generation system 12, enable efficient plasma excitation.
[0062] Certain embodiments disclosed herein, in particular each module and / or unit, utilize circuits (e.g., one or more circuits) to implement the standards, protocols, methodologies, or techniques disclosed herein, to operably connect two or more components, generate information, process information, analyze information, generate signals, encode / decode signals, convert signals, transmit and / or receive signals, control other devices, etc. Any type of circuit may be used.
[0063] In embodiments, the circuit may include one or more computing devices, such as processors (e.g., microprocessors), central processing units (CPUs), digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), system-on-a-chip (SoCs), etc., or any combination thereof, and may include individual digital or analog circuit elements or electronic devices, or combinations thereof. In embodiments, the circuit may include implementations of hardware circuits (e.g., implementations in analog circuits, implementations in digital circuits, etc., and combinations thereof).
[0064] In embodiments, the circuit includes a combination of the circuit and a computer program product having software instructions or firmware instructions stored in one or more computer-readable memories, which cooperate to cause a device to execute one or more protocols, methodologies, or techniques described herein. In embodiments, the circuit includes, for example, a microprocessor or a part of a microprocessor that requires software, firmware, etc., for operation. In embodiments, the circuit includes one or more processors or parts thereof, and associated software, firmware, hardware, etc.
[0065] This application may refer to quantities and figures. Unless otherwise specified, such quantities and figures are not limiting but should be considered examples of quantities or figures that may be associated with this application. In this regard, this application may use the term “plural” when referring to quantities or figures. In this regard, the term “plural” means a number greater than 1, e.g., 2, 3, 4, 5, etc. The terms “about,” “approximately,” “nearly,” etc. mean ±5% of the stated value.
Claims
1. A radio frequency generation system (12) for plasma excitation in plasma processing, The aforementioned radio frequency generation system (12) Includes a signal generation unit (18) configured to generate at least three radio frequency signals having different frequencies, The signal generation unit (18) has a shared signal generation output on which the radio frequency signal is output. The radio frequency generation system (12) includes a broadband amplification stage (24), which is connected to the shared signal generation output (20), amplifies the radio frequency signal, and is configured to output the amplified radio frequency signal at the amplification stage output (26) of the amplification stage (24). The radio frequency generation system (12) includes a matching network (28) connected to the amplification stage output (26) of the amplification stage (24) and configured to set a predetermined impedance to the amplification stage output (26) of the amplification stage (24). The impedance between the amplification stage output (26) and the matching network (28) is not equal to 50 ohms. The radio frequency generation system (12) uses the complex impedance (Z) of the plasma processing. Ｐ The plasma processing impedance acquisition unit (34) is configured to acquire the following: The radio frequency generation system (12) includes a control unit (42), which is connected to the plasma processing impedance acquisition unit (34) for signal transmission, and the signal generation unit (18), the amplification stage (24), and / or the matching network (28) are connected to the acquired complex impedance (Z) of the plasma processing. Ｐ ) is configured to be controlled based on, Radio frequency generation system (12).
2. A first radio frequency signal having a first frequency, a second radio frequency signal having a second frequency, and a third radio frequency signal having a third frequency are provided, wherein the third frequency is three times the first frequency and twice the second frequency. A radio frequency generation system (12) according to claim 1.
3. The signal generation unit (18) is configured to individually adjust the frequency of each of the at least three radio frequency signals independently of the other radio frequency signals. A radio frequency generation system (12) according to claim 1 or 2.
4. The signal generation unit (18) is configured to individually and independently adjust the amplitude and / or phase of each of the at least three radio frequency signals, apart from the other radio frequency signals. A radio frequency generation system (12) according to any one of claims 1 to 3.
5. The matching network (28) includes at least one adjustable capacitor (30), an adjustable inductor, and / or an adjustable reactor, and the control unit (42) is configured to adjust the capacitance of the adjustable capacitor (30), the inductance of the adjustable inductor, and / or the reactance of the adjustable reactor. A radio frequency generation system (12) according to any one of claims 1 to 4.
6. The plasma processing impedance acquisition unit (34) is characterized by including a directional coupler (38) configured to separate forward waves and backward waves from each other, and a measurement unit (40) configured to acquire the forward power of the forward wave and the reflected power of the backward wave. A radio frequency generation system (12) according to any one of claims 1 to 5.
7. The plasma processing impedance acquisition unit (34) is characterized by including at least one sensor (44) configured to measure voltage, current, and the phase between the voltage and the current. A radio frequency generation system (12) according to any one of claims 1 to 6.
8. The radio frequency generation system (12) includes an input interface (46) configured to receive at least one radio frequency signal from an external signal source, and is characterized in that a bypass (50) is provided between the input interface (46) and the amplification stage (24). A radio frequency generation system (12) according to any one of claims 1 to 7.
9. The control unit (42) is characterized by comprising a control unit interface (52) used for receiving control signals. A radio frequency generation system (12) according to any one of claims 1 to 8.
10. The signal generation unit (18) is configured to perform adjustment of the voltage waveform in order to generate the radio frequency signal. A radio frequency generation system (12) according to any one of claims 1 to 9.
11. A plasma generation system (10) for plasma excitation in plasma processing, The plasma generation system (10) includes a plasma chamber (14) and A radio frequency generation system (12) according to any one of claims 1 to 10 is included. The radio frequency generation system (12) is connected to at least one electrode (16) located in the plasma chamber (14), Plasma generation system (10).
12. The plasma processing impedance acquisition unit (34) is characterized by being positioned closer to the at least one electrode (16) than the matching network (28). Plasma generation system (10) according to claim 11.
13. A method for exciting the plasma used in plasma processing, The aforementioned method, A step of generating at least three radio frequency signals having different frequencies using a signal generation unit (18), The step of outputting the radio frequency signal via the shared signal generation output (20) of the signal generation unit (18), The steps include amplifying the radio frequency signal using a broadband amplification stage (24), and The amplification stage output (26) of the amplification stage (24) includes the step of outputting an amplified radio frequency signal, The predetermined impedance of the amplification stage output (26) of the amplification stage (24) is set using a matching network (28), and the impedance between the amplification stage output (26) and the matching network (28) is not equal to 50 ohms. The complex impedance (Z) of the plasma processing Ｐ ) is acquired using the plasma processing impedance acquisition unit (34), The signal generation unit (18), the amplification stage (24), and / or the matching network (28) are used to obtain the complex impedance (Z) of the plasma processing. Ｐ ) is controlled based on, method.