RF power amplifier unit for coupling RF signals for plasma processing feed systems and plasma processing systems

Abstract

The invention relates to an RF power amplifier unit (10) for coupling an RF signal, in particular for a plasma processing feed system, the unit comprises: a) a first RF power amplifier stage arrangement (AU1), b) a second RF power amplifier stage arrangement (AU2), c) a first transmission line arrangement (TL1) and a second transmission line arrangement (TL2), each connected to the output of the two RF power amplifier stage arrangements (AU1, AU2), d) a coupling line arrangement (TLC), the coupling line arrangement is designed to transmit the sum of the output powers of the two RF power amplifier stage arrangements (AU1, AU2), tL2) are each connected to a coupling line arrangement (TLC) in order to be able to transmit the output power of the first RF power amplifier stage arrangement (AU1) and the second RF power amplifier stage arrangement (AU2) to the coupling line arrangement (TLC), f) a measuring arrangement (M1) designed to determine a variable describing the power output by the RF power amplifier stage arrangement and / or the RF power amplifier unit, the measuring device is positioned on at least one of the transmission line device (TL1, TL2) and / or the coupling line device (TLC).

Description

Technical Field

[0001] The present invention relates to an RF power amplifier unit for coupling RF signals, particularly for plasma processing power supply systems and plasma processing systems, the RF power amplifier unit being designed for power of ≥2 kW, preferably ≥4 kW, and frequencies in the range of 2 MHz to 200 MHz, particularly in the range of 10 MHz to 50 MHz.

[0002] The present invention also relates to a plasma processing power supply system and a plasma processing system.

[0003] The present invention also includes a method for supplying power to a load, particularly a plasma processing unit. Background Technology

[0004] A plasma processing power supply system is configured to power a plasma processing apparatus. A plasma processing apparatus is a device that generates and sustains plasma to initiate and maintain the processing. This can be associated with a gas laser excitation device. Specifically, it can be associated with a plasma processing apparatus. Using such a plasma processing apparatus, materials, and especially their surfaces, can be treated, for example, coated, etched, or activated. Such plasma processing apparatuses are used, for example, in the manufacture of architectural glass, photovoltaic modules, displays, semiconductor components such as microcontrollers or semiconductor memory chips. Because these are high-precision processes, the requirements for such plasma processing apparatuses and therefore the plasma processing power supply systems that power them are very high in terms of measurement and control accuracy, reliability, continuous operation, and efficiency. Such plasma processing power supply systems are typically designed for power outputs of ≥2 kW, preferably ≥4 kW, and frequencies ranging from 2 MHz to 200 MHz, particularly from 10 MHz to 50 MHz. Such plasma processing power supply systems typically have one or more high-frequency signal sources designed to collectively provide the required power and to regulate the required power according to the processing specifications. In addition, plasma processing power supply systems typically have one or more impedance matching circuits designed to match the impedance at the output of the high-frequency signal source with the impedance at the input of the plasma processing system.

[0005] The output power of high-frequency signal sources, especially RF power amplifier stages with transistor amplifiers, is limited to a few hundred W to a few kilowatts by currently available transistors. Therefore, to achieve higher output power, multiple high-frequency signal sources must be connected together. This synthesis can be implemented in an RF power amplifier unit.

[0006] RF power amplifier units are designed to exhibit minimal losses over a wide bandwidth. In particular, such RF power amplifier units are required for high-frequency signal sources used in plasma processing feed systems. As the requirements for measurement and control accuracy and stability in plasma processing feed systems continue to increase, the corresponding requirements for RF power amplifier units used in these systems also continue to grow. At high power levels, RF power amplifier units typically require significant space. Furthermore, interference effects due to undesirable emissions also increase.

[0007] For example, according to DE 20 2016 008 958 U1, a power combiner is known for such a process.

[0008] The drawback of this type of power combiner is that it is only suitable for limited power output. This is because the number of high-frequency signal sources that can be positioned around the power combiner is limited by space.

[0009] Purpose of the invention

[0010] Therefore, the object of the present invention is to provide an RF power amplifier unit that reliably synthesizes multiple RF power amplifier stages within a limited space and at a high power level, and monitors the output power using a measuring device. Summary of the Invention

[0011] This objective is achieved by the RF power amplifier unit according to independent claim 1. Further advantageous developments of the invention are derived from the dependent claims and / or the specification.

[0012] According to the present invention, an RF power amplifier unit for coupling RF signals is provided, the RF power amplifier unit being designed for power of ≥2 kW, preferably ≥4 kW, and frequencies in the range from 2 MHz to 200 MHz, particularly from 10 MHz to 50 MHz, the RF power amplifier unit comprising:

[0013] a) A first RF power amplifier stage device having a first output impedance, positioned on a first heat sink portion.

[0014] b) A second RF power amplifier stage with a second output impedance, positioned on the second heat sink section.

[0015] c) A first transmission line device connected to the output of a first RF power amplifier stage and designed to transmit the output power of the first RF power amplifier stage and designed to have a first line impedance equal to the output impedance of the first RF power amplifier stage.

[0016] d) A second transmission line device connected to the output of the second RF power amplifier stage and designed to transmit the output power of the second RF power amplifier stage and designed to have a second line impedance equal to the output impedance of the second RF power amplifier stage.

[0017] e) A coupling line device designed to transmit the sum of the output power of a first RF power amplifier stage, a second RF power amplifier stage, and a further RF power amplifier stage, and designed to be used for coupling line impedance, wherein the coupling line impedance depends on the first line impedance, the second line impedance, and the further line impedance.

[0018] f) The first transmission line device and the second transmission line device are each connected to the coupling line device so that the output power of the first RF power amplifier stage device and the second RF power amplifier stage device can be transmitted to the coupling line device.

[0019] g) A measuring device designed to determine variables describing the power output by an RF power amplifier stage and / or an RF power amplifier unit, the measuring device being positioned on at least one of a transmission line device and / or a coupling line device.

[0020] An RF power amplifier stage device refers to a device that may include multiple RF power amplifier stages, coupling elements, and energy absorbers.

[0021] An energy absorber can be a component suitable for extracting electrical energy from a power combiner and converting it into heat, such as a resistor. However, it is also conceivable that the component is designed to convert at least a portion of the energy so that this portion can be reused at another location.

[0022] The coupling element can be, for example, an inductor or a coupling line of a predetermined length, such as λ / 4. For example, if multiple coupling elements are all inductors, they can advantageously always have the same inductance value, and in particular, they can have the same construction. Multiple coupling elements can be positioned in a way that hardly affects each other, and in particular, does not affect each other at all. "Hardly affects" means that the influence is so small that it is negligible according to the laws of physics.

[0023] A radiator section refers to a part of a cooling unit. A cooling unit may be designed at least partially as a cooling plate. A cooling unit may include multiple sections made of different materials. Examples of such cooling units are disclosed and described in detail in the following publications: WO 2019 / 072894 A1, WO 2013 / 068004 A1, WO 2014 / 207185 A1.

[0024] This provides an RF power amplifier unit that reliably combines the output power of two RF power amplifier stage devices within a limited space, and monitors the power of the RF power amplifier stage devices and / or the output power of the RF power amplifier unit using measuring devices. Furthermore, shielding is achieved by arranging the RF power amplifier stage devices on a heat sink section. This prevents destructive effects such as unwanted radiation.

[0025] This may also be because RF power amplifier stages typically cannot be positioned very close to each other, due to the nature of the RF power amplifier stages:

[0026] - Typically generates a large amount of heat, requiring it to be cooled by a cooling unit, and / or

[0027] - Due to their high power generation, they carry such high current and voltage that they will negatively affect each other by emitting high-frequency fields.

[0028] One solution is to place the RF power amplifier stages further apart and / or shield them appropriately. In both cases, the outputs of the RF power amplifier stages can only be positioned at a certain distance from each other. Therefore, they have a distance that is disadvantageous for the power combiner. This disadvantage can be overcome by an advantageous combination of the aforementioned transmission line and coupling line arrangements.

[0029] In another aspect of the RF power amplifier unit, the following relationship applies to the coupling line impedance relative to the first and second line impedances: ZC' = 1 / (1 / Z1' + 1 / Z2'), where

[0030] ZC': Coupled line impedance

[0031] Z1': First line impedance, and

[0032] Z2': Second line impedance.

[0033] In this way, interference caused by reflections can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0034] In another aspect of the RF power amplifier unit, the first line impedance and the second line impedance can be equal.

[0035] In this way, interference caused by reflections can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0036] In another aspect of the RF power amplifier unit, the first line impedance and the second line impedance can each be twice the coupling line impedance.

[0037] In this way, interference caused by reflections can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0038] In another aspect, the RF power amplifier unit may also include:

[0039] a) One, and more particularly several, additional RF power amplifier stages, each having an additional output impedance and each positioned on an additional heatsink portion, and

[0040] b) One, and in particular several, additional transmission line devices, each connected to a corresponding output of an additional RF power amplifier stage and each designed to transmit the output power of the additional RF power amplifier stage and each designed to use an additional line impedance equal to the output impedance of the additional RF power amplifier stage, wherein

[0041] c) The coupling line device is designed to transmit the sum of the output power of the first RF power amplifier stage, the second RF power amplifier stage, and the additional RF power amplifier stage, and is designed to be used for the coupling line impedance, wherein the coupling line impedance depends on the first line impedance, the second line impedance, and the additional line impedance, and wherein...

[0042] d) The other transmission line devices are each connected to the coupling line device so that the output power of the other RF power amplifier stage devices can be transmitted to the coupling line device.

[0043] In this way, the advantages of the present invention can be achieved even at higher power levels.

[0044] In another aspect of the RF power amplifier unit, the following relationship applies to the coupling line impedance relative to the first line impedance, the second line impedance, and the additional line impedance: ZC' = 1 / (1 / Z1' + 1 / Z2' + 1 / Zn'), where

[0045] ZC': Coupled line impedance

[0046] Z1': First line impedance

[0047] Z2': Second line impedance, and

[0048] Zn': Additional line impedance.

[0049] in This means that n can be a natural number, so n = 1, 2, 3, 4... The number n indicates the number of line impedances. Taking n = 3 as an example, the third line impedance Z3' yields another line impedance Zn', and the following applies: ZC' = 1 / (1 / Z1' + 1 / Z2' + 1 / Z3'). Taking n = 4 as an example, the third line impedance Z3' and the fourth line impedance Z4' yield another line impedance Zn', and the following applies: ZC' = 1 / (1 / Z1' + 1 / Z2' + 1 / Z3' + 1 / Z4'). In this way, this can also be continued for larger values ​​of n.

[0050] The number of line impedances is derived from the number of transmission line devices in the RF power amplifier unit.

[0051] In this way, even at higher power levels, interference caused by reflections can be further reduced, and measurements can be further improved, and therefore control can be further improved.

[0052] In another aspect of the RF power amplifier unit, the additional line impedance may be equal to the first line impedance and / or the second line impedance.

[0053] In this way, even at higher power levels, interference caused by reflections can be further reduced, and measurements can be further improved, and therefore control can be further improved.

[0054] In another aspect of the RF power amplifier unit, the additional line impedance can each be N times larger than the coupling line impedance, where N = the number of the first transmission line device, the second transmission line device, and the nth transmission line device.

[0055] In this way, even at higher power levels, interference caused by reflections can be further reduced, and measurements can be further improved, and therefore control can be further improved.

[0056] In another aspect of the RF power amplifier unit, one, particularly multiple, especially preferred, all transmission line devices may include:

[0057] - A signal conductor designed to transmit the corresponding output signal of an RF power amplifier stage.

[0058] - A reference conductor that is electrically connected to a potential that remains constant relative to a reference ground, and in particular, the reference ground.

[0059] In this way, interference caused by radiation can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0060] In another aspect of the RF power amplifier unit, the coupling line device may include:

[0061] - A coupling signal conductor designed to transmit the synthesized output signal of an RF power amplifier stage.

[0062] - A coupling reference conductor, which is electrically connected to a potential that remains constant relative to the reference ground, and in particular the reference ground.

[0063] In this way, interference caused by radiation can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0064] In another aspect of the RF power amplifier unit, one, particularly several, especially preferred, all transmission line devices can be designed as microstrip lines.

[0065] In this way, interference caused by radiation can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0066] In another aspect of the RF power amplifier unit, one, particularly more, especially preferred, all transmission line devices can be designed as coaxial cables.

[0067] In this way, interference caused by radiation can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0068] In another aspect of the RF power amplifier unit, the coupling line device can be designed as a microstrip line.

[0069] In this way, interference caused by radiation can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0070] In another aspect of the RF power amplifier unit, the coupling line device can be designed as a coaxial line.

[0071] In this way, interference caused by radiation can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0072] In another aspect of the RF power amplifier unit, one, particularly a plurality, especially preferred, all transmission line devices can be connected to the corresponding RF power amplifier stage device by means of pins at their connection points, particularly at their signal connection points, which can be, in particular, a part of the corresponding transmission line device.

[0073] This makes production easier and enables highly reliable and accurate measurements.

[0074] In another aspect of the RF power amplifier unit, one, particularly a plurality, especially preferably all RF power amplifier stage devices can be positioned on a printed circuit board, which in turn is positioned on a corresponding heat sink portion, and in particular, transmission line devices are connected to the electrical contacts of these printed circuit boards.

[0075] In this way, interference caused by radiation can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0076] In another aspect of the RF power amplifier unit, the heat sinks can each be located on a separate cooling unit.

[0077] In this way, interference caused by radiation can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0078] In another aspect of the RF power amplifier unit, the heat sink section can be positioned to surround the space it surrounds.

[0079] In this way, interference caused by radiation can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0080] In another aspect of the RF power amplifier unit, the coupling line assembly can be positioned within the space surrounded by the heat sink section.

[0081] In this way, interference caused by radiation can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0082] In another aspect of the RF power amplifier unit, one, particularly several, especially preferred, all transmission line devices can be positioned largely within a space surrounded by a heat sink section.

[0083] In this way, interference caused by radiation can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0084] In another aspect of the RF power amplifier unit, the measuring device can be positioned within a space surrounded by a heat sink section.

[0085] In this way, interference caused by radiation can be further reduced, measurements can be further improved, and therefore control can be further improved.

[0086] In another aspect of the RF power amplifier unit, one, particularly multiple, especially preferred, all RF power amplifier stage devices can be positioned outside the space surrounded by a heat sink section.

[0087] In this way, interference caused by radiation can be further reduced, and measurements and controls can be further improved.

[0088] In another aspect of the RF power amplifier unit, multiple, particularly preferred, all RF power amplifier stage devices can be constructed identically, and in particular can be positioned linearly symmetrically with respect to the coupling line device.

[0089] This improves the reliability of the RF power amplifier unit because the same components can be used.

[0090] In another aspect of the RF power amplifier unit, the cooling unit can be designed, particularly implemented as a fluid-cooled cooling unit, especially a cooling plate, for example for cooling with air, liquid or a combination of both.

[0091] This can improve the reliability of the RF power amplifier unit because the RF power amplifier unit does not generate much heat, and temperature-sensitive components remain operational for a longer period of time.

[0092] In another aspect of the RF power amplifier unit, one, particularly multiple, and especially preferably all RF power amplifier stage devices may have multiple amplifier stages, the outputs of which are connected to the input of a power combiner section, which includes:

[0093] - Multiple inputs and one output.

[0094] - Multiple coupling elements, particularly inductors, each connecting the input of a power combiner section to its output.

[0095] - An energy absorber, particularly a resistor, connected to the input of the power combiner section; in particular, multiple energy absorbers, particularly resistors, connected, particularly in a star configuration, to the input of the power combiner section.

[0096] In this way, even at higher power levels, interference caused by reflections can be further reduced, and measurements can be further improved, and therefore control can be further improved.

[0097] In another aspect, the RF power amplifier unit may include a power combiner, which includes:

[0098] - Multiple power combiner sections,

[0099] - A plurality of additional transmission line devices, each of which is connected to the output of the power combiner section.

[0100] - Coupler wire device, and

[0101] - Especially the balance line.

[0102] In this way, even at higher power levels, interference caused by reflections can be further reduced, and measurements can be further improved, and therefore control can be further improved.

[0103] The balancing line can be a line with a fixed characteristic impedance and a length of n*λ / 2, where, .

[0104] For example, such a balance line is described in DE 10 2023 111 812.9, filed May 5, 2023, the entire contents of which are incorporated herein by reference.

[0105] Such a balanced line can be used to avoid cross-feeding of RF power amplifier stages used as high-frequency signal sources and uneven distribution of reflected output power. If the amplitude, phase, or internal impedance of the RF power amplifier stages connected to the power combiner is uneven, a push-pull signal detrimental to the high-frequency signal source can be generated. Alternatively, if the reflected power distribution is uneven, the phase and / or amplitude of each RF power amplifier stage, as well as the load impedance, may change. This can lead to excessive stress on the most heavily loaded RF power amplifier stage.

[0106] To avoid this situation, the balance line can be connected to the input of the power combiner.

[0107] Balanced lines can also be designed as balanced circuits with additional components such as resistors.

[0108] In particular, the specified characteristic impedance of the balanced line can be equal to the characteristic impedance at the corresponding input terminal.

[0109] The specified characteristic impedance of the balanced line can be an integer multiple of the characteristic impedance at the corresponding input terminal.

[0110] The specified characteristic impedance of the balanced line can be specifically equal to an integer fraction of the characteristic impedance at the corresponding input terminal.

[0111] The specified characteristic impedance of the balancing line can be specifically equal to 25 Ω, 50 Ω or 100 Ω.

[0112] λ usually refers to the wavelength of the radio frequency signal within the operating frequency range, especially within the corresponding line (i.e., within the balanced line) at the center frequency of the operating frequency range.

[0113] This means that n can be a natural number, that is, n = 1, 2, 3, 4, ...

[0114] "Operating frequency range" refers to the frequency range within which the power combiner and the RF power amplifier stage that can be connected to the power combiner operate; that is, the power combiner and the RF power amplifier stage are designed for this frequency range. This can be a very narrow operating frequency range, such as 13.54 MHz to 13.58 MHz, or a slightly wider band, such as 13.06 MHz to 14.06 MHz. In both cases, the center frequency will be 13.56 MHz. The operating frequency range is typically specified as a nominal frequency range by the power combiner manufacturer. This will vary depending on the application of the power combiner. If the power combiner is part of an RF power amplifier unit, the power combiner is also designed for at least this operating frequency range.

[0115] This objective is also achieved by a plasma processing feed system comprising at least one RF power amplifier unit as described above and an impedance matching circuit connected downstream therefrom. For example, a power combiner as described above can be used particularly advantageously, ensuring specific reliability and stability of the system.

[0116] This objective is also achieved by a plasma processing system comprising a plasma processing power supply system as described above and a plasma processing apparatus connected to an impedance matching circuit.

[0117] For example, the power combiner described above can be used particularly advantageously and ensures specific reliability and stability of the system.

[0118] This objective is also achieved by a method for supplying power to the load, particularly the plasma processing apparatus, via the power amplifier unit as described above, and especially via an impedance matching circuit connected downstream of the power amplifier unit, wherein the impedance matching unit is particularly preferably connected to the plasma processing apparatus, wherein...

[0119] a) The first output power is generated by the first RF power amplifier stage.

[0120] b) The second RF power amplifier stage generates the second first output power.

[0121] c) The first output power from the first transmission line device and

[0122] d) Second output power from the second transmission line device

[0123] e) Transmission to the coupling line device

[0124] f) The coupling line device transmits the output power of the first RF power amplifier stage and the second RF power amplifier stage, which are coupled together, to the output of the power amplifier unit, and

[0125] a) Use measuring devices to determine the amount describing the power output of the RF power amplifier stage and / or RF power amplifier unit at one of the transmission line and / or coupling line devices, and

[0126] g) Supply these coupled output powers to the load.

[0127] This method can be particularly advantageous in solving the task. Attached Figure Description

[0128] Preferred exemplary embodiments of the invention are schematically illustrated in the accompanying drawings, and a more detailed description is given below with reference to the drawings.

[0129] Figure 1 A schematic diagram of a first embodiment of the RF power amplifier stage unit according to the present invention is shown;

[0130] Figure 2 A schematic diagram of a second embodiment of the RF power amplifier unit according to the present invention is shown;

[0131] Figure 3 A schematic diagram of an embodiment of the RF power amplifier unit according to the present invention is shown;

[0132] Figure 4 Another embodiment of the RF power amplifier unit according to the present invention is shown;

[0133] Figure 5 A plasma processing system with an RF power amplifier stage unit according to the present invention is shown. Detailed Implementation

[0134] Figure 1A first embodiment of the RF power amplifier unit 10 according to the present invention is shown. The RF power amplifier unit 10 includes two RF power amplifier stage devices AU1 and AU2, two cooling units CP1 and CP2, two heat sink portions CS1 and CS2, two printed circuit boards PCB1 and PCB2, two transmission line devices TL1 and TL2, a measuring device M1, and a coupling line device TLC. The first RF power amplifier stage device AU1 is positioned on the first printed circuit board PCB1. The first RF power amplifier stage device AU1 is also positioned on the first heat sink portion CS1 via the first printed circuit board PCB1. The first heat sink portion CS1 is part of the first cooling unit CP1. The second RF power amplifier stage device AU2 is positioned on the second printed circuit board PCB2. The second RF power amplifier stage device AU2 is also positioned on the second heat sink portion CS2 via the second circuit board PCB2. The second heat sink portion CS2 is part of the second cooling unit CP1.

[0135] Two cooling units, CP1 and CP2, are positioned to surround space V1.

[0136] A first transmission line device TL1 connects a first RF power amplifier stage device AU1 to a coupling line device TLC and has a first signal conductor SL1 and a first reference conductor BL1. A second transmission line device TL2 connects a second RF power amplifier stage device AU2 to the coupling line device TLC and has a second signal conductor SL2 and a second reference conductor BL2. The coupling line device TLC has a coupling signal conductor SLC and a coupling reference conductor BLC.

[0137] Two signal conductors SL1 and SL2 are designed to transmit the corresponding output signals of RF power amplifier stages AU1 and AU2. Two reference conductors BL1 and BL2 represent the reference potentials of the two signal conductors SL1 and SL2 and are electrically connected to a potential that remains constant relative to a reference ground. This potential itself can also be the reference ground.

[0138] Two transmission line devices, TL1 and TL2, are placed together and connected to a coupling line device, TLC. The coupling signal line, SLC, is designed to transmit the combined output signal of the two RF power amplifier stages, AU1 and AU2. The coupling reference conductor, BLC, represents the reference potential of the coupling signal conductor, SLC, and is electrically connected to a potential that is constant relative to a reference ground. This potential can itself be the reference ground. A measurement device, M1, is integrated into the coupling line device, TLC, and is designed to determine the combined power of the two RF power amplifier stages, AU1 and AU2.

[0139] The measuring device M1 can, for example, include at least one directional coupler or current and voltage sensors. Via at least one directional coupler, the measuring device M1 can measure the power of the RF signal transmitted from the RF power supply unit 10 towards the impedance matching circuit 11 or the load. Preferably, the measuring device M1 can also measure the power of the RF signal reflected back to the RF power supply unit 10 at the impedance matching circuit 11. The power of the RF signal transmitted from the RF power supply unit 10 towards the impedance matching circuit 11 can also be determined via the current and voltage sensors. The power of the RF signal reflected by the impedance matching circuit 11 can also be detected by the current and voltage sensors.

[0140] For example, a typical measuring device M1 is shown in one of the following publications: WO2019 / 185424 A1, WO2013 / 143537 A1, US2009 / 0140722 A1, US2006 / 0232265 A1, DE 20 2011 051 371 U1.

[0141] Figure 2 Another embodiment of the RF power amplifier unit 10 according to the present invention is shown. The RF power amplifier unit 10 is constructed in a very similar manner to the RF power amplifier unit 10 in Figure 1 . However, it has an additional third RF power amplifier stage device AUn. The third RF power amplifier stage device AUn is positioned on the third radiator part CSn. The third radiator part CSn is part of the third cooling unit C3. The third RF power amplifier device AUn is combined with the first RF power amplifier device AU1 and the second RF power amplifier device AU2 via the third transmission line device TLn and is connected to the coupled power device TLC. The third transmission line device TLn has the same structure as the two transmission line devices TL1, TL2 from Figure 1 . Compared with the embodiment in Figure 1 , the RF power amplifier unit in this embodiment does not have any printed circuit board. The RF power amplifier stage devices AU1, AU2, AUn are directly positioned on the cooling units CP1, CP2, CPn. Additionally, the first cooling unit CP1 has the first radiator part CS1.

[0142] Can be found in the description of Figure 1 a more detailed description of the individual components that are also mentioned in Figure 1 .

[0143] Overall, the RF power amplifier unit 10 in this embodiment is designed to synthesize the output signals of the three RF power amplifier stage devices AU1, AU2, AUn and further transmit the combined power via the coupled power device TLC.

[0144] Figure 3 Another embodiment of the power amplifier unit 10 according to the present invention is shown. The power amplifier unit 10 includes a power combiner 1, four RF power amplifier stages AS1 to AS4, and two cooling units CP1 and CP2. The power combiner 1 includes four input terminals In1 to In4, a main output terminal OUT, four coupling elements designed as inductors L1 to L4, and a balancing circuit B. The RF power amplifier stages AS1 to AS4 are connected to the input terminals In1 to In4. The inductors L1 to L4 connect the input terminals In1 to In4 to the main output terminal OUT.

[0145] The first two input terminals, In1 and In2, are connected to the first output terminal O1 via the first two inductors, L1 and L2, and the last two input terminals, In3 and In4, are connected to the second output terminal O2 via the last two inductors, L3 and L4. Then, the two output terminals O1 and O2 are connected to the main output terminal OUT.

[0146] Four inductors L1 to L4 and four RF power amplifier stages AS1 to AS4 are positioned on two cooling units CP1 and CP2. The first two inductors L1 and L2 and the first two RF power amplifier stages AS1 and AS2 are on the first cooling unit CP1. The RF power amplifier stages AS1 and AS2, together with components of the first power combiner section 1a (i.e., the coupling elements of inductors L1 and L2 and the energy absorbers of resistors R1 and R2), form the first RF power amplifier stage device AU1. The latter two inductors L3 and L4 and the latter two RF power amplifier stages AS3 and AS4 are positioned on the second cooling unit CP2. The RF power amplifier stages AS3 and AS4, together with components of the second power combiner section 1b (i.e., the coupling elements of inductors L3 and L4 and the energy absorbers of resistors R3 and R4), form the second RF power amplifier stage device AU2.

[0147] The balancing circuit B has four energy absorbers designed as resistors R1 to R4 and a balancing line W1 of length n*λ / 2. The balancing circuit B connects four input terminals In1 to In4. For this purpose, the first two input terminals In1 and In2 are connected to each other via the first two resistors R1 and R2 positioned on the first cooling unit CP1. The first resistor R1 is connected to the first input terminal In1, and the second resistor R2 is connected to the second input terminal In2. Similarly, the last two input terminals In3 and In4 are connected to each other via the last two resistors R3 and R4 positioned on the second cooling unit CP2. The third resistor R3 is connected to the third input terminal In3, and the fourth resistor R4 is connected to the fourth input terminal In4. The balancing line W1 then connects all four input terminals In1 to In4 to each other.

[0148] In this way, two, or more than two, RF power amplifier stages AU1, AU2 can be connected to each other. If more than two RF power amplifier stages AU1, AU2 are connected together, multiple balanced lines can be connected in a star configuration.

[0149] A single, particularly multiple, especially preferred, RF power amplifier stage device AU1, AU2 may also have more than two RF power amplifier stages AS1, AS2. Therefore, these RF power amplifier stage devices may also have more than two components in the power combiner sections 1a, 1b, i.e., more than two coupling elements designed here as inductors L1, L2 and more than two energy absorbers designed here as resistors R1, R2.

[0150] Figure 3 The possible connection arrangement of the two output terminals O1 and O2 of the two RF power amplifier stage devices AU1 and AU2 with the main output terminal OUT is also shown.

[0151] The first output terminal O1 of the first RF power amplifier stage AU1 is connected to the first transmission line device TL1. The first transmission line device TL1 has a first signal conductor SL1 and a first reference conductor BL1. The second output terminal O2 of the second RF power amplifier stage AU2 is connected to the second transmission line device TL2. The second transmission line device TL2 has a second signal conductor SL2 and a second reference conductor BL2.

[0152] Two signal conductors SL1 and SL2 are designed to transmit the corresponding output signals of RF power amplifier stage devices AU1 and AU2. Two reference conductors BL1 and BL2 represent the reference potentials of the two signal conductors SL1 and SL2 and are electrically connected to a potential that remains constant relative to the reference ground. In this case, this potential itself is the reference ground GND.

[0153] Two transmission line devices TL1 and TL2 are placed together and connected to a coupling line device TLC. The coupling line device TLC has a coupled signal line SLC and a coupled reference line BLC. The coupled signal line SLC is designed to transmit the combined output signal of the two RF power amplifier stage devices AU1 and AU2. The coupled reference conductor BLC represents the reference potential of the coupled signal conductor SLC and is electrically connected to a potential that is constant relative to the reference ground. In this case, this potential itself is the reference ground GND. The coupling line device TLC is connected to the main output terminal OUT of the power amplifier unit 10.

[0154] In this case, the two transmission line devices TL1 and TL2 are designed as microstrip lines (MSL).

[0155] Figure 4An embodiment of the power amplifier unit 10 according to the present invention is shown. The power amplifier unit 10 and... Figure 3 The power amplifier unit 10 is very similar, shown only from a different perspective, and the connection arrangement of the two output terminals O1, O2 of the two RF power amplifier stage devices AU1, AU2 to the main output terminal OUT is designed as a coaxial line CXL. Descriptions of the two transmission line devices TL1, TL2, the two signal conductors SL1, SL2, the two reference conductors BL1, BL2, the coupling line device TLC, the coupled signal line SLC, and the coupled reference conductor BLC can be found in... Figure 3 It was found in the description.

[0156] The two cooling units CP1 and CP2 can each have heat sink portions CS1 and CS2. It is also conceivable that multiple heat sink portions CS1 and CS2 are positioned on a common cooling plate, but spaced apart from each other (not shown in the figure). For example, the first heat sink portion CS1 can be positioned on the first side of the cooling unit, and the second heat sink portion CS2 can be positioned on the back side of the same cooling unit.

[0157] and Figure 3 Compared to the power amplifier unit 10 in the previous example, the power amplifier unit 10 here has two synthesizer circuit boards PCB1 and PCB2.

[0158] The first synthesizer circuit board PCB1 is positioned on the first heat sink portion CS1, and therefore also on the first cooling unit CP1 in this embodiment. The second synthesizer circuit board PCB2 is positioned on the second heat sink portion CS2, and therefore also on the second cooling unit CP2 in this embodiment. Furthermore, the power amplifier unit 10 has... Figure 3 Power combiner 1. Four RF power amplifier stages AS1 to AS4 are shown, each distributed into RF power amplifier stage devices AU1 and AU2. Four coupling elements designed as inductors L1 to L4, the main output terminal OUT, and the balancing circuit B are also shown. The balancing circuit B includes four energy absorbers designed as resistors R1 to R4 and a balancing line W1 of length n*λ / 2.

[0159] The first two RF power amplifier stages, AS1 and AS2, are positioned on the first amplifier circuit board PCB12. These two stages, along with PCB12, are positioned on the first heat sink portion CS1, and therefore, in this embodiment, also on the first cooling unit CP1. The latter two RF power amplifier stages, AS3 to AS4, are positioned on the second amplifier circuit board PCB34. These two stages, along with PCB12, are positioned on the second heat sink portion CS2, and therefore, in this embodiment, also on the second cooling unit CP2.

[0160] The first synthesizer circuit board PCB1 can also be combined with the first amplifier circuit board PCB12 to form a common circuit board.

[0161] The second synthesizer circuit board PCB2 can also be combined with the second amplifier circuit board PCB34 to form a common circuit board.

[0162] This simplifies manufacturing and reduces the number of cable connections between circuit boards, making the entire system more reliable.

[0163] The first two inductors L1 and L2 and the first two resistors R1 and R2 are located on the first synthesizer circuit board PCB1. The last two inductors L3 and L4 and the last two resistors R3 and R4 are located on the second synthesizer circuit board PCB2.

[0164] Figure 5 A plasma processing system 17 with a plasma processing power supply system 12 is shown.

[0165] The plasma processing power supply system 12 has a power amplifier unit 10 with a power combiner 1. These can be designed as described above.

[0166] The plasma processing power supply system 12 also includes an impedance matching circuit 11.

[0167] The main output terminal OUT of the power combiner 1 is connected to the input terminal of the impedance matching circuit 11. The output terminal of the impedance matching circuit 11 is connected to the load, in this case, the plasma processing device in the plasma chamber 13.

[0168] Plasma chamber 13 includes:

[0169] - Substrate 15, which is treated by plasma 16, for example by coating or etching.

[0170] - Electrode 14, through which RF power is coupled to plasma chamber 13 to ignite and sustain plasma 16.

[0171] Impedance matching circuit 11 is designed to transform the input impedance of the plasma treatment at its output terminal to the output impedance of power amplifier unit 10. For example, designs of such plasma treatment systems and / or impedance matching circuits are described in the following published applications: DE 10 2009 001 355 A1, DE 10 2011 007 597 A1, DE 10 2011007 598 A1, WO 2021 / 209390 A1, WO 2021 / 255250 A1.

Claims

1. An RF power amplifier unit (10) for coupling RF signals, in particular for plasma processing feed systems and plasma processing systems, designed for powers > 2 kW, preferably > 4 kW, and frequencies in the range from 2 MHz to 200 MHz, in particular in the range from 10 MHz to 50 MHz, comprising: a) a first RF power amplifier stage arrangement (AU1) with a first output impedance (Z1) positioned on a first heat sink portion (CS1), b) a second RF power amplifier stage arrangement (AU2) with a second output impedance (Z2) positioned on a second heat sink portion (CS2), c) a first transmission line arrangement (TL1) connected to an output of the first RF power amplifier stage arrangement (AU1) and designed to transmit the output power of the first RF power amplifier stage arrangement and designed for a first line impedance (Z1') equal to the output impedance (Z1) of the first RF power amplifier stage arrangement (AU1), d) a second transmission line arrangement (TL2) connected to an output of the second RF power amplifier stage arrangement (AU2) and designed to transmit the output power of the second RF power amplifier stage arrangement and designed for a second line impedance (Z2') equal to the output impedance (Z2) of the second RF power amplifier stage arrangement, e) a coupling line arrangement (TLC) designed to transmit the sum of the output powers of the first RF power amplifier stage arrangement (AU1) and the second RF power amplifier stage arrangement (AU2) and designed for a coupling line impedance (ZC') dependent on the first line impedance (Z1') and the second line impedance (Z2'), f) the first transmission line arrangement (TL1) and the second transmission line arrangement (TL2) each connected to the coupling line arrangement (TLC) in order to be able to transmit the output powers of the first RF power amplifier stage arrangement (AU1) and the second RF power amplifier stage arrangement (AU2) to the coupling line arrangement (TLC), g) a measuring arrangement (M1) designed to determine a variable describing the power output by the RF power amplifier stage arrangement and / or the RF power amplifier unit, the measuring arrangement being positioned on at least one of the transmission line arrangements (TL1, TL2) and / or the coupling line arrangement (TLC).

2. The RF power amplifier unit (10) according to the preceding claim 1, wherein The coupling line impedance (ZC') fulfils the following relationship with respect to the second line impedance (Z2') and the first line impedance (Z1'): ZC' = (Z1' -1 + Z2' -1 ) -1 .

3. The RF power amplifier unit (10) according to any of the preceding claims, wherein The second line impedance (Z2') and the first line impedance (Z1') are equal.

4. The RF power amplifier unit (10) according to any of the preceding claims, wherein The second line impedance (Z2') and the first line impedance (Z1') are each twice as large as the coupling line impedance (ZC'). The second line impedance (Z2') and the first line impedance (Z1') are each twice as large as the coupling line impedance (ZC').

5. The RF power amplifier unit (10) according to any of the preceding claims, wherein, The RF power amplifier unit (10) further comprises: a) one, in particular a plurality of, further RF power amplifier stage devices (AUn), each having a further output impedance (Zn) and each being positioned on a further heat sink portion (CSn), and b) one, in particular a plurality of, further transmission line devices (TLn), each being connected to a respective output of the further RF power amplifier stage devices (AUn) and each being designed to transmit the output power of the further RF power amplifier stage devices (AUn) and each being designed for a further line impedance (Zn') being equal to the output impedance (Zn) of the further RF power amplifier stage devices, wherein c) the coupling line device (TLC) is designed to transmit the sum of the output powers of the first RF power amplifier stage device (AU1) and the second RF power amplifier stage device (AU2) and the further RF power amplifier stage devices (AUn) and is designed for a coupling line impedance (ZC'), wherein the coupling line impedance (ZC') depends on the first line impedance (Z1'), the second line impedance (Z2') and the further line impedance (Zn'), and wherein d) the further transmission line devices (TLn) are each connected to the coupling line device (TLC) in order to be able to transmit the output power of the further RF power amplifier stage devices (AUn) to the coupling line device (TLC).

6. The RF power amplifier unit (10) according to any of the preceding claims, wherein The coupling line impedance (ZC') fulfils the following relationship with respect to the first line impedance (Z1'), the second line impedance (Z2') and the further line impedance (Zn'): ZC' = (Z1' -1 + Z2' -1 + Zn' -1 ) -1 .

7. The RF power amplifier unit (10) according to any of the preceding claims, wherein The further line impedance is equal to the second line impedance (Z2') and / or the first line impedance (Z1').

8. The RF power amplifier unit (10) according to any of the preceding claims, wherein, The further line impedance (Z2', Z1') is each N times as large as the coupling line impedance (ZC'), wherein N = the number of the first transmission line device (TL1), the second transmission line device (TL2) and the n-th transmission line device (TLn).

9. The RF power amplifier unit (10) according to any of the preceding claims, wherein, The one, in particular the plurality, in particular all, transmission line devices (TL1, TL2, TLn) comprise: - a signal conductor (SL1, SL2, SLn) designed to transmit a respective output signal of the RF power amplifier stage devices (AU1, AU2, AUn), - a reference conductor (BL1, BL2, BLn) electrically connected to a potential which is constant with respect to a reference ground, in particular a reference ground (GND).

10. The RF power amplifier unit (10) according to any of the preceding claims, wherein, The coupling line device (TLC) comprises: - a coupling signal conductor (SLC) designed to transmit a combined output signal of the RF power amplifier stage devices (AU1, AU2, AUn), - a coupling reference conductor (BLC) electrically connected to a potential which is constant with respect to a reference ground, in particular a reference ground (GND).

11. The RF power amplifier unit (10) according to any of the preceding claims, wherein, One, in particular multiple, in particular preferably all transmission line devices (TL1, TL2, TLn) are designed as microstrip lines (MSL).

12. The RF power amplifier unit (10) according to any of the preceding claims, wherein, One, in particular multiple, in particular preferably all transmission line devices (TL1, TL2, TLn) are designed as coaxial lines (CXL).

13. The RF power amplifier unit (10) according to any of the preceding claims, wherein, The coupling line device (TLC) is designed as a microstrip line (MSL).

14. The RF power amplifier unit (10) according to any of the preceding claims, wherein, The coupling line device (TLC) is designed as a coaxial line (CXL).

15. The RF power amplifier unit (10) according to any of the preceding claims, wherein, One, in particular multiple, in particular preferably all transmission line devices (TL1, TL2, TLn) are connected to the respective RF power amplifier stage device (AU1, AU2, AUn) by means of a pin connection, in particular by means of a signal connection thereof, the pin preferably being part of the respective transmission line device (TL1, TL2, TLn).

16. The RF power amplifier unit (10) according to any of the preceding claims, wherein, One, in particular multiple, in particular preferably all RF power amplifier stage devices (AU1, AU2, AUn) are positioned on a printed circuit board (PCB1, PCB2, PCBn), which in turn is positioned on a respective heat sink portion (CS1, CS2, CSn), and in particular the transmission line devices (TL1, TL2, TLn) are connected to electrical contacts of these printed circuit boards (PCB1, PCB2, PCBn).

17. The RF power amplifier unit (10) according to any of the preceding claims, wherein, The heat sink portions (CS1, CS2, CSn) are each positioned on a separate cooling unit (CP1, CP2, CPn).

18. The RF power amplifier unit (10) according to any of the preceding claims, wherein, The heat sink portions (CS1, CS2, CSn) are positioned such that they surround a space (V1) enclosed thereby.

19. The RF power amplifier unit (10) according to any of the preceding claims, wherein, The coupling line device (TLC) is positioned within the space (V1) surrounded by the heat sink portions (CS1, CS2, CSn).

20. The RF power amplifier unit (10) according to any of the preceding claims, wherein, One, in particular multiple, in particular preferably all transmission line devices (TL1, TL2, TLn) are positioned mostly within the space (V1) surrounded by the heat sink portions (CS1, CS2, CSn).

21. The RF power amplifier unit (10) according to any of the preceding claims, wherein, The measurement device (M1) is positioned within the space (V1) surrounded by the heat sink portions (CS1, CS2, CSn).

22. The RF power amplifier unit (10) according to any of the preceding claims, wherein, One, in particular multiple, in particular preferably all RF power amplifier stage devices (AU1, AU2, AUn) are positioned outside the space (V1) surrounded by the heat sink portions (CS1, CS2, CSn).

23. The RF power amplifier unit (10) according to any of the preceding claims, wherein, The multiple, in particular preferably all RF power amplifier stage devices (AU1, AU2, AUn) are identically configured and in particular positioned line-symmetrically with respect to the coupling line device (TLC).

24. The RF power amplifier unit (10) according to any of the preceding claims, wherein, The cooling units (CP1, CP2, CPn) are designed, in particular embodied, as fluid-cooled cooling units, in particular cooling plates, for example for cooling by means of air, liquid or a combination of both.

25. The RF power amplifier unit (10) according to any of the preceding claims, wherein, One, in particular multiple, in particular preferably all RF power amplifier stage devices (AU1, AU2, AUn) have multiple amplifier stages (AS1, AS2, AS3, AS4), the outputs of which are connected to inputs of a power combiner portion (1a, 1b), the power combiner portion comprising: - multiple inputs and one output, - a plurality of coupling elements, in particular inductors, which each connect the input to the output of the power combiner section (1a, 1b), - an energy absorber, in particular a resistor, which connects the input of the power combiner section (1a, 1b).

26. RF power amplifier unit (10) according to any of the preceding claims, comprising a power combiner (1), the power combiner comprising: - a plurality of power combiner sections (1a, 1b), - a plurality of further transmission line means (TL1, TL2), which are each connected to an output of the power combiner section (1a, 1b), - a coupling line means (TLC), and - in particular a balanced line (W1).

27. Plasma processing feed system (12) comprising at least one RF power amplifier unit (10) according to any of the preceding claims and an impedance matching circuit (11) connected downstream of the RF power amplifier unit.

28. Plasma processing system (17) comprising a plasma processing feed system (12) according to claim 27 and a plasma processing device connected to the impedance matching circuit (11).

29. Method for powering a load, in particular a plasma process, by a power amplifier unit (10) according to any of the preceding claims 1 to 26 and in particular by an impedance matching circuit (11) connected downstream of the power amplifier unit, which is in turn particularly preferably connected to a plasma processing device, wherein a) a first output power is generated by a first RF power amplifier stage means (AU1), b) a second first output power is generated by a second RF power amplifier stage means, c) the first output power from a first transmission line means (TL1), and d) the second output power from a second transmission line means (TL2), e) are transmitted to a coupling line means (TLC), f) the coupling line means transmits the coupled together output power of the first RF power amplifier stage means (AU1) and the second RF power amplifier stage means (AU2) to an output of the power amplifier unit (10), and g) a measurement means (M1) is used to determine a quantity describing the power output by the RF power amplifier stage means (AU1, AU2) and / or the RF power amplifier unit (10), the measurement means being on one of the transmission line means (TL1, TL2) and / or the coupling line means (TLC), and h) these coupled together output powers are supplied to a load.

30. RF power amplifier unit (10) according to claim 29, wherein the first RF power amplifier stage means (AU1) and the second RF power amplifier stage means (AU2) are each connected to a respective one of the transmission line means (TL1, TL2), and wherein the coupling line means (TLC) is connected to the outputs of the transmission line means (TL1, TL2).

31. RF power amplifier unit (10) according to claim 29 or 30, wherein the first RF power amplifier stage means (AU1) and the second RF power amplifier stage means (AU2) are each connected to a respective one of the power combiner sections (1a, 1b), and wherein the coupling line means (TLC) is connected to the outputs of the power combiner sections (1a, 1b).

32. RF power amplifier unit (10) according to claim 29, 30 or 31, wherein the first RF power amplifier stage means (AU1) and the second RF power amplifier stage means (AU2) are each connected to a respective one of the power combiner sections (1a, 1b), and wherein the coupling line means (TLC) is connected to the outputs of the power combiner sections (1a, 1b).

33. RF power amplifier unit (10) according to any of the preceding claims, wherein the first RF power amplifier stage means (AU1) and the second RF power amplifier stage means (AU2) are each connected to a respective one of the power combiner sections (1a, 1b), and wherein the coupling line means (TLC) is connected to the outputs of the power combiner sections (1a, 1b).

34. RF power amplifier unit (10) according to any of the preceding claims, wherein the first RF power amplifier stage means (AU1) and the second RF power amplifier stage means (AU2) are each connected to a respective one of the power combiner sections (1a, 1b), and wherein the coupling line means (TLC) is connected to the outputs of the power combiner sections (1a, 1b).

35. RF power amplifier unit (10) according to any of the preceding claims, wherein the first RF power amplifier stage means (AU1) and the second RF power amplifier stage means (AU2) are each connected to a respective one of the power combiner sections (1a, 1b), and wherein the coupling line means (TLC) is connected to the outputs of the power combiner sections (1a, 1b).

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