High-frequency power coupler for a power converter for an industrial process assembly

Abstract

The invention relates to a high-frequency power coupler (1) for coupling a plurality of HF input signals in order to form an HF output signal for outputting HF power to an industrial process assembly (1), preferably a plasma process assembly, gas laser excitation, or heating assembly, the HF power coupler (1) having: a. a plurality of HF inputs (11, 12, 13, 14, 15), b. an HF output (17), c. a coupling unit (19), and d. an impedance matching line (20) which extends from the coupling unit (19) to the HF output (17) and, for this purpose, has a specified length between the two ends, wherein e. the impedance matching line (20) has a branching line (50) with no-load termination such that the impedance matching line (20) is designed to bring about a specified impedance matching function between the output of the coupling unit (19) and the HF output (7), and f. the specified length is less than ʎ / 6 and greater than ʎ / 10.

Description

[0001] 2023P00598WG

[0002] 1

[0003] High-frequency power coupler for a power converter for an industrial process arrangement

[0004] The invention relates to a high-frequency power coupler for coupling multiple RF input signals to a single RF output signal, for supplying RF power to an industrial process arrangement, preferably a plasma process arrangement, gas laser excitation, or heating arrangement. The invention further relates to an electrical power converter for an industrial process arrangement, preferably a plasma process arrangement, gas laser excitation, or heating arrangement, comprising such an RF power coupler.

[0005] In this application, "HF" stands for high frequency. High frequency here refers to a frequency of at least 1 MHz. Preferably, it also refers to a frequency of no more than 100 MHz.

[0006] Such industrial process setups are often operated at very high power levels. Very high power here refers to an electrical output power of at least 20 kW at an RF output. These applications are also referred to as high-power applications.

[0007] A plasma process setup, especially for gas laser excitation, particularly for high-frequency RF applications, can be very complex and often has to meet high requirements, for example, regarding performance, efficiency, operational readiness / availability, and space requirements. This also requires, for example, the efficient transmission of high electrical RF power, which may necessitate precise electrical matching or adjustment.

[0008] Due to space constraints in such industrial processes, it is necessary to save space in the control cabinets to meet all customer requirements. Furthermore, it is desirable to accommodate more RF power converters and RF power couplers in a single cabinet, which leads to volume issues. An overly cramped design often results in insufficient mechanical stability and reduced resistance to electromagnetic interference because shielding is often inadequate and cables are routed too close together.

[0009] The invention is based on the objective of improving an RF power coupler of the type mentioned above, in particular to make it more space-saving and at the same time to improve its stability.

[0010] This problem is solved by an RF power coupler with the features according to claim 1. Further aspects are disclosed in the description and in the dependent claims. In one aspect, an RF power coupler for coupling several RF input signals to an RF output signal for supplying RF power to an industrial process arrangement, preferably a plasma process arrangement, gas laser excitation, or heating arrangement, is disclosed. The RF power coupler comprises: a. several RF inputs, b. an RF output, c. a coupling unit, d. an impedance matching line extending from the coupling unit to the RF output and having a predetermined length between these two ends, e. wherein the impedance matching line has a branch line with an open-circuit termination, such that this impedance matching line is designed to effect a predetermined impedance matching from the output of the coupling unit to the RF output (7), f.where the specified length is less than Ä / 6 and greater than Ä / 10.

[0011] A branch line with an open-circuit termination is also referred to as an "open-stub".

[0012] In this revelation, "Ä" stands for the wavelength of the radio frequency. This wavelength depends on the material in which the wave propagates. In the case of an impedance matching line, this could be the material of the insulating layer. The insulating layer is described in more detail below.

[0013] The impedance transformation from an input impedance of an impedance matching line to an output impedance without a branch line is achieved by the branch-free impedance matching line itself. The length of the impedance matching line can be significantly reduced because the impedance transformation from the output impedance without a branch line to the output impedance with a branch line is performed very elegantly using the branch line. Overall, this significantly reduces the space required for the impedance matching line compared to an arrangement without a branch line.

[0014] In one aspect, the RF power coupler is designed for a power output of 1 kW to 10 kW at one, or preferably all, RF inputs. Because the RF power coupler is designed to integrate high power into a compact design, it can be installed in control cabinets or industrial plants, saving space. This is particularly advantageous when space is limited but high RF power is still required. The power range is 1 kW to 10 kW. 2023P00598WG

[0015] The 3 can cover a wide range of RF applications, from small laboratory setups to large industrial applications such as plasma processes, gas lasers, or heating systems. This versatility makes the RF power coupler attractive for a broad spectrum of applications.

[0016] In one aspect, the RF power coupler is designed for a high frequency in the range of 1 MHz to 100 MHz, preferably in the range of 10 MHz to 30 MHz, particularly in the range of 13 MHz to 14 MHz and / or in the range of 26 MHz to 28 MHz, most preferably at 13.56 MHz or 27.12 MHz. The frequency range of 1 MHz to 100 MHz covers many industrial and scientific applications. These include, among others, plasma excitation, induction heating, and certain applications in high-frequency technology, such as the control of gas lasers. This makes the coupler usable in many different fields. The specific frequencies of 13.56 MHz and 27.12 MHz are common industrial ISM frequencies in many countries, where "ISM" stands for "Industry, Science, and Medicine."These frequencies are approved for use in industrial applications in many countries, allowing the RF power coupler to operate in many countries without additional frequency licenses. This can simplify deployment and reduce regulatory hurdles. Matching the coupler to these frequencies enables precise impedance matching and efficient power transfer. At these frequencies, it is possible to transmit high power with low losses, leading to improved overall system energy efficiency. These advantages make the RF power coupler not only versatile and adaptable but also particularly efficient and suitable for specific industrial applications requiring the aforementioned high power output.

[0017] In one aspect, the branch line with open-circuit termination is designed as a microstrip cable. Microstrip cables are flat conductive traces arranged on an insulating layer, also known as a dielectric. This design allows for a very compact construction, which can be particularly advantageous when space is limited in industrial applications, such as in control cabinets. Microstrip cables can be easily mounted on a printed circuit board (PCB), which can reduce manufacturing costs and production effort. The production of such cables is standardized, enabling fast and cost-effective manufacturing. The microstrip design offers relatively low losses in high-frequency signals, thus enabling efficient transmission and distribution of RF energy.This can be important in applications within the aforementioned frequency ranges where energy losses need to be minimized. In one aspect, the branch line is connected closer to the RF output than to the coupling unit. The short distance between the branch line and the output can reduce the cable length over which the signal must be transmitted. This reduces power losses caused by attenuation in the line, resulting in higher efficiency of the RF power coupler.

[0018] In one aspect, the branch line is connected directly before the RF output. The position of the branch line directly before the RF output allows for targeted manipulation of the output characteristics, such as the phase and amplitude of the output signal. This can help to optimally adapt the RF output to the requirements of the connected industrial process setup.

[0019] In one aspect, the branch line is shorter than Φ / 20. Although the line is short, it can still be used for fine-tuning the impedance. In combination with other impedance matching elements, it helps to make the matching more precise without significantly lengthening the signal path or introducing additional losses.

[0020] In one aspect, the branch cable is shorter than 60 cm. A shorter branch cable allows for a more compact and space-saving design of the RF power coupler. This can be advantageous when the coupler has to be installed in confined spaces, as is often the case in industrial applications.

[0021] In one aspect, the impedance matching line is arranged planarly on an insulating layer. A planar arrangement of the impedance matching line on an insulating layer allows for a flat and compact design that requires little space. This is particularly advantageous in space-constrained applications, such as in control cabinets or industrial equipment. Planar lines on insulating layers can be easily fabricated on printed circuit boards or other flat substrates. A planar arrangement on an insulating layer allows for relatively precise impedance control by adjusting the properties of the insulating layer and the geometry of the line. This enables accurate impedance matching, thereby reducing reflections and improving the efficiency of high-frequency transmission.Planar conductors applied to insulating layers can be effectively combined with cooling structures. Their flat design allows the conductor to be placed in contact with heat sinks or mounting plates for efficient heat dissipation, which can be crucial in high-performance applications. These advantages make the planar arrangement of impedance matching conductors on an insulating layer a beneficial solution (2023P00598WG).

[0022] 5 for precise, efficient and robust transmission of high-frequency signals in various industrial applications.

[0023] In one aspect, the impedance matching line and the branch line are arranged on the same insulating layer. This shared arrangement on the same insulating layer allows for a flat and space-saving design, which is particularly advantageous in applications with limited installation space. This reduces the space required in the enclosure or control cabinet. When both lines are located on the same insulating layer, the impedance ratios between the impedance matching line and the branch line can be controlled very precisely. This can lead to better matching of the overall system, reducing reflections and increasing the efficiency of power transmission. Placing both lines on the same insulating layer can also enable a standardized production method and reduce the number of components and manufacturing steps required.This can reduce production costs and manufacturing complexity. Since both conductors are located on the same layer, the generated heat can be distributed evenly across the entire surface and transferred to cooling devices. This can support uniform cooling of the components.

[0024] In one aspect, the RF power coupler features an upper mounting plate, a middle mounting plate, and a lower mounting plate, with the middle mounting plate positioned between the upper and lower plates. This placement of the middle mounting plate between the upper and lower plates contributes to a particularly robust construction. This layered structure can provide the coupler with greater mechanical strength and resistance to vibrations and mechanical stresses commonly encountered in industrial environments. The middle mounting plate can act as a thermal buffer, distributing heat evenly between the upper and lower plates. This can facilitate uniform cooling, for example, when all three plates are used as cooling surfaces, which is particularly important in high-power applications to prevent overheating.The layered structure with the middle plate allows the upper and lower mounting plates to effectively shield the RF components from external electromagnetic interference. The middle plate can provide an additional barrier, improving the system's electromagnetic compatibility. The three-layer arrangement supports a modular design, allowing components to be easily added or replaced. This can be advantageous, for example, when the coupler needs to be adapted for different applications or when specific parts need to be replaced during maintenance. This three-layer design can offer a combination of mechanical robustness, thermal management, and electrical shielding, 2023P00598WC.

[0025] 6 which can be advantageous for the reliable and efficient use of the RF power coupler in demanding industrial environments.

[0026] In one aspect, the impedance matching line is positioned between both the upper and middle mounting plates, and between the lower and middle mounting plates. This placement between the plates provides additional shielding against electromagnetic interference. This can reduce the risk of electromagnetic interference that could impair the performance of the impedance matching line and ensure more stable signal transmission. The contact of the impedance matching line with the adjacent mounting plates allows the heat generated during the transmission of the RF energy to be evenly transferred to and dissipated by the plates. This can support effective temperature management within the RF power coupler. The close coupling between the plates ensures that the impedance matching line remains stable and evenly positioned.This can help ensure that the impedance matching remains constant along the entire length of the line, thus reducing power losses during signal transmission. This arrangement of the impedance matching line can enable efficient use of space, increased mechanical and electrical stability, and simultaneously support temperature management within the assembly.

[0027] In one aspect, the coupling unit can be implemented on a printed circuit board (PCB). Integrating the coupling unit onto a PCB allows for a space-saving and compact solution. This reduces the required installation space, which is particularly advantageous in modern, densely packed electronic systems. Implementing the coupling unit on a PCB can facilitate mass production and reduce manufacturing costs compared to discrete components. Integration on a PCB allows for precise definition of connections and impedances. This ensures consistent, reliable performance of the coupling unit and reduces potential deviations or interference. The coupling unit on a PCB can be easily connected to other circuits and components also housed on the same board.This can reduce cabling effort and simplify the overall system design. Direct connections on the circuit board, eliminating long cable runs, can reduce signal loss and unwanted reflections. This can lead to more efficient signal transmission and improved coupling unit performance. A circuit board implementation can be designed to effectively dissipate the heat generated by the electronic components. A circuit board coupling unit can be easily integrated into modular systems, increasing the expandability and flexibility of the entire system. This allows for the addition of extra components or functions on the same circuit board or via additional boards. When the coupling unit is securely mounted on the circuit board, the risk of assembly or connection errors caused by loose cables or imprecise connections is reduced.This can ensure greater operational reliability and reduce the need for maintenance.

[0028] In one aspect, the branch line is positioned between the upper and middle mounting plates and / or between the lower and middle mounting plates. This can further improve the aforementioned properties. Positioning the branch line between the plates can ensure stable mechanical guidance and reduce the risk of the line shifting due to external influences. This can enable consistent electrical performance and help reduce the risk of mismatches.

[0029] In one aspect, at least one of the mounting plates is designed as a cooling plate with a channel for conveying a coolant. The design of the cooling channels within the mounting plates not only contributes to heat dissipation but can also reinforce the structural integrity of the plates. This allows the mechanical properties of the mounting plates to be maintained while simultaneously improving cooling. Since cooling is achieved by the fluid in the channels, noisy, wear-prone, and failure-prone fans can often be eliminated. Furthermore, this reduces the risk of dust accumulation and / or distribution, which is desirable in certain industrial environments, such as cleanrooms in the semiconductor industry.

[0030] In one aspect, the middle mounting plate is designed as a cooling plate with a channel for circulating a coolant. When positioned between the upper and lower plates, the middle mounting plate can act as a central cooling surface. The coolant in the channels can absorb heat from the surrounding components on both sides and efficiently dissipate it. This can ensure a uniform temperature distribution throughout the RF power coupler. The middle mounting plate's cooling function helps prevent heat buildup in the center of the assembly. The channels can dissipate heat directly, which can keep the operating temperature low and reduce the risk of thermally induced performance degradation.

[0031] In one aspect, both the upper and lower mounting plates are designed as cooling plates with a channel for coolant flow. The ability to route coolant through both plates can increase heat dissipation capacity. This can support operation under higher power demands without component overheating. Using the mounting plates themselves as cooling surfaces can also enable a space-saving design. 2023P00598WQ

[0032] 8. This eliminates the need for a separate space for external heat sinks. This can simplify the integration of the RF power coupler into existing industrial systems.

[0033] In one aspect, an insulating layer is provided between the impedance matching line and one, or preferably several, mounting plates, or even all mounting plates. Here, "insulating layer" refers to an electrically insulating layer, not a thermally insulating layer. This insulating layer can positively influence the dielectric properties of the impedance matching line. This can enable more precise impedance control, thereby improving impedance matching to RF components and promoting smooth signal transmission. This insulating layer between the impedance matching line and the mounting plates can contribute to the safety, stability, and performance of the RF power coupler by providing electrical, mechanical, and thermal protection.

[0034] In one aspect, the insulating layer is made of PTFE. "PTFE" is an abbreviation for polytetrafluoroethylene. PTFE has a very high dielectric strength, meaning it can function very well as an electrical insulator. It can effectively reduce the risk of short circuits and unwanted electrical connections between the impedance matching line and the mounting plates. PTFE has a low dielectric loss factor, which can reduce energy losses in high-frequency signals. This can help ensure that signal transmission over the impedance matching line remains efficient and that the quality of the RF signals is maintained. PTFE is extremely temperature-resistant and remains stable over a wide temperature range. This allows the insulating layer to remain resilient even at high operating temperatures without losing its insulating properties, which can be particularly advantageous in high-power applications.PTFE is resistant to many chemicals and environmental influences. This protects it from corrosion and chemical reactions, which can increase the lifespan of the insulating layer and surrounding components, even in demanding industrial environments. The dielectric constant of PTFE remains stable over a wide frequency range. This can facilitate precise impedance matching, as the electrical properties of the insulating layer do not change significantly with frequency. PTFE is relatively easy to process into thin films and form into various shapes. This can simplify its integration as an insulating material in complex assemblies such as RF power couplers.Choosing PTFE as the insulating layer material can ensure reliable electrical insulation, stable high-frequency transmission, and high resistance to thermal and chemical stresses, thus enhancing the overall system's quality and longevity. In one aspect, the insulating layer is made of ceramic. Ceramic materials possess very high dielectric strength, enabling them to act as highly effective insulators. They offer robust protection against electrical breakdowns, reducing the risk of short circuits between the impedance matching line and the mounting plates. Ceramic is also extremely heat-resistant, retaining its insulating properties even at very high temperatures. This makes it particularly suitable for applications where high operating temperatures may occur and contributes to system stability.Ceramic materials exhibit low dielectric losses, which can contribute to the efficient transmission of RF signals. This low power loss ensures that energy transfer via the impedance matching line is not impaired. The dielectric constant of ceramics remains stable even under varying temperatures and frequencies. This facilitates precise impedance matching in the high-frequency range and can ensure consistent performance of the RF power coupler. Ceramics are resistant to many aggressive chemicals and environmental influences. This makes them resistant to corrosion and ensures that the insulating layer retains its properties even in demanding industrial environments. Ceramics also have high thermal conductivity compared to many other insulators.This allows for better heat distribution, which can lead to a more stable operating temperature of the surrounding components. Choosing ceramic as the material for the insulating layer can offer a combination of excellent electrical insulation, high thermal and mechanical stability, and resistance to external influences, thus enhancing the reliability and durability of the RF power coupler.

[0035] The dielectric constant of the material influences the required length of the impedance matching conductor. The larger this dielectric constant of the material (Δr), the smaller, shorter, and therefore more space-saving the impedance matching conductor can be. Typical values ​​are 9 for ceramics and 2 for PTFE.

[0036] Therefore, ceramics would be the preferred choice.

[0037] It should be noted that ceramic is brittle and can break, especially on the relatively large surfaces required here. These surfaces are at least 500 cm². 2 .

[0038] Additionally, due to the poor formability of ceramics, air gaps can form between the mounting plates and the insulating layer. Because of the different dielectric properties of air and ceramic, this can lead to high field strengths in the air gaps. This can cause corona or partial discharges, which can be detrimental to efficiency and potentially damaging to the material. 2023P00598WG

[0039] 10

[0040] Therefore, it can also be advantageous here to use a material that is less brittle, even if the dielectric constant of the material 8r is significantly smaller.

[0041] It should be noted that PTFE is deformable.

[0042] In one aspect, the impedance matching cable is made of metal. Due to the high electrical conductivity of metal, less heat is generated during the transmission of RF energy. This can help keep the operating temperature of the cable low and reduce the need for elaborate cooling measures. Metals have high thermal conductivity, which allows the generated heat to be dissipated quickly. This can contribute to better temperature distribution and prevent certain areas from overheating. The use of metal as the material for the impedance matching cable can enable reliable transmission of high-frequency signals, as metallic materials operate stably and with low loss even at high frequencies. This is advantageous for a uniform impedance match and the reduction of signal distortion.

[0043] One aspect of the impedance matching cable is its use of aluminum. Metallic materials like aluminum offer excellent electrical conductivity. This allows high-frequency signals to be transmitted with low resistance, which can increase signal transmission efficiency and reduce energy losses. Aluminum combines this advantage with the additional benefits of low weight, low cost, high corrosion resistance, and low emissions, which is particularly desirable in the semiconductor industry.

[0044] One aspect of the impedance matching cable is its use of copper. Metallic materials like copper offer exceptionally good electrical conductivity. This allows RF signals to be transmitted with low resistance, which can increase signal transmission efficiency and reduce energy losses. Copper combines this advantage with the additional benefits of very good thermal conductivity.

[0045] In one aspect, the impedance matching cable has a meandering design. This allows for efficient use of space without unnecessarily increasing inductance. The meandering shape enables the cable to be housed in a small space. This is particularly useful when the physical length of the cable is critical for impedance matching, but available space is limited. The meandering design allows for fine-tuning of the cable's resonant characteristics to achieve precise matching at specific frequencies. This is especially advantageous in high-frequency applications where accurate cable tuning is essential. Due to its shape, a meandering cable can better absorb and compensate for certain mechanical stresses and vibrations. (See 2023P00598WG)

[0046] 11. The structure can be designed to be more resistant to mechanical influences and remain stable for longer.

[0047] In one aspect, the branch line has a meandering design. This allows for the aforementioned advantages of the branch line.

[0048] In one aspect, the mounting plates are arranged parallel to each other and make contact with the impedance matching line on both sides via the insulating layer, thus providing cooling. This two-sided cooling allows the impedance matching line to handle higher electrical power without the risk of overheating. This can make the RF power coupler more resistant to power spikes and thermal loads. With this cooling method, additional external cooling devices such as fans or separate heat sinks can be reduced or eliminated, as the integrated plates already ensure effective heat dissipation. This saves space and simplifies the overall design.

[0049] In one aspect, the central mounting plate features a recess for routing the impedance matching cable. This allows for a particularly low-radiation configuration. The recess in the central mounting plate enables precise and secure routing of the impedance matching cable. This ensures the cable remains stable in place and preserves the system's mechanical structure even under external influences. Integrating the cable into the recess allows for better utilization of vertical installation space. The cable can be routed through the plate without requiring additional width, enabling a more compact design. The recess also provides better protection for the cable against mechanical damage. The central plate can offer an additional physical barrier, protecting the sensitive impedance matching cable from shocks, vibrations, or other external influences.The recess allows for close contact between the conductor and the plate, which facilitates heat transfer. This enables the plate to directly absorb heat from the impedance matching conductor and conduct it to a cooling system, thus promoting a more uniform temperature distribution. The precise positioning of the conductor by the recess ensures a stable electrical connection, contributing to the reliability of the high-frequency transmission. This allows for consistent impedance matching, reducing signal loss. The recess also provides clear routing for the conductor, simplifying installation. Furthermore, the impedance matching conductor remains easily accessible during maintenance without requiring disassembly of the entire assembly.This design of the middle mounting plate with a recess can provide a well-thought-out solution for integrating the impedance matching line, which is the 2023P00598WG.

[0050] 12

[0051] It can reduce space requirements while simultaneously improving the stability and efficiency of the system.

[0052] In one aspect, the insulating layer between the impedance matching conductor and the center mounting plate is also located in the recess area to electrically isolate the impedance matching conductor from the center mounting plate. This insulation allows the electrical environment of the impedance matching conductor to remain stable, which can be important for consistent impedance matching. This can contribute to smooth high-frequency transmission and help reduce signal reflections, thus increasing the overall system efficiency. The insulating layer can also provide additional protection when transmitting high voltages, such as those that can occur in high-frequency applications. It can reduce the risk of high voltages arcing to the center mounting plate, thereby increasing operational reliability.The insulating layer can provide an additional physical barrier, protecting the impedance matching conductor from direct mechanical stresses through the recess. This can reduce the risk of abrasion or damage that could result from movement or vibration. The insulating layer can also help regulate heat conduction between the impedance matching conductor and the center mounting plate. This allows for more controlled heat dissipation and prevents overheating of the conductor while maintaining electrical insulation.

[0053] In one aspect, one, and preferably several, mounting plate(s) has a cooling channel for conveying a coolant. The cooling channels in the mounting plates enable direct and uniform dissipation of the heat generated during the operation of the RF components. The coolant efficiently carries away the heat, thus maintaining the assembly temperature at a constant level. The integrated cooling channels significantly reduce the risk of overheating throughout the assembly. Even at high power levels and during extended periods of operation, this allows the components to operate within a safe temperature range. The ability to actively dissipate heat enables the system to operate stably even under high loads and demanding operating conditions. Constant cooling ensures that performance is not compromised by thermal effects.If the cooling channels are arranged in several or all mounting plates, heat can be dissipated evenly throughout the entire system. This can reduce the formation of hotspots and ensure a balanced temperature distribution, which can help distribute the stress on the components evenly. Constant cooling can reduce the thermal stress on the electrical and mechanical components. This can extend the service life of the components by reducing thermal cycling and material fatigue (2023P00598WG).

[0054] 13. The cooling channels may be less pronounced. If the cooling channels are integrated directly into the mounting plates, the need for external cooling systems such as additional heat sinks or fans can be eliminated. This can save space and simplify the design, especially for compact assemblies. With cooling channels in multiple plates, the cooling capacity can be tailored to specific needs. The flow rate and temperature of the coolant can be adjusted to ensure targeted cooling depending on the heat generation.

[0055] In one aspect, one, or preferably several, mounting plates are connected to a constant potential. Mounting plates at a constant potential can act as a shield, thereby reducing electromagnetic interference within the system. This can contribute to a more stable and interference-free transmission of the high-frequency signals. Connecting to a constant potential ensures that the electrical potential of the plates remains uniform. This can create a stable electrical environment for the components and wiring in the RF power coupler, which can improve signal quality and help reduce reflections. When all mounting plates are at the same potential level, voltage differences between the plates can be reduced or eliminated. This can lower the risk of unwanted voltage flashovers or sparking that could cause damage.

[0056] In one aspect, one, or in particular several, preferably all mounting plates are connected to ground. Connecting the mounting plates to ground can further increase the electrical safety of the system. Potential leakage currents or electrical disturbances can be dissipated, which can reduce the risk of short circuits or uncontrolled voltages.

[0057] In one aspect, one, or more specifically several, and preferably all, of the mounting plate(s) can be connected to a metallic enclosure. Connecting the mounting plates to a metallic enclosure can create a closed shield that attenuates external electromagnetic interference and prevents interference radiation from escaping the system. This can improve the electromagnetic compatibility of the RF system. A metallic enclosure connected to the mounting plates can serve as a ground point. This allows electrical interference currents or overvoltages to be dissipated, which can increase the electrical safety of the system and protect sensitive components. The connection to a robust metallic enclosure can provide mechanical protection for the internal components. The enclosure can protect the plates and electronic components from physical influences such as shocks, vibrations, or mechanical stress.Metallic enclosures can exhibit good thermal conductivity, thus serving as an additional heat dissipation surface. When the mounting plates are directly connected to the enclosure, heat can be efficiently transferred from the plates to the enclosure and thus better distributed. Connecting the mounting plates to a common metallic enclosure ensures that all plates are at the same electrical potential. This reduces voltage differences between the plates, minimizing the risk of unwanted electrical effects such as flashovers. A metallic enclosure can also serve as a central grounding point for the entire system. Connecting the mounting plates to the enclosure facilitates system grounding and ensures reliable dissipation of electrical disturbances. The metallic enclosure provides protection against environmental factors such as moisture, dust, and chemicals.This can contribute to the longevity of the mounting plates and the integrated electronics, as they are protected from corrosion and wear. Connecting the mounting plates to the housing enables a compact and integrated design, where all components are housed securely and in a space-saving manner. This can facilitate the integration of the RF system into existing industrial plants.

[0058] In one aspect, coolant connections are provided for one, in particular several, and preferably all mounting plates. Using coolant connections directly on the mounting plates eliminates the need for additional external cooling devices. This can save space and simplify the design of the entire RF power coupler. Targeted cooling of each plate can prevent local overheating. This can contribute to a uniform temperature distribution throughout the assembly and prevent thermal stress points that could impair the performance and lifespan of the components.

[0059] In one aspect, an electrical power converter for an industrial process arrangement, preferably a plasma process arrangement, gas laser excitation, or heating arrangement, is disclosed. This power converter comprises: a. An RF power coupler as described in this disclosure, b. Several RF amplifier arrangements designed to be connected to the RF inputs of the RF power coupler.

[0060] The RF power coupler enables the aggregation of signals from multiple RF amplifier arrays and their combined transmission to the industrial process array. This ensures efficient transmission of high-frequency energy, thereby increasing the overall system performance. The combination of RF- 2023P00598WG

[0061] 15

[0062] Power couplers and RF amplifier arrays can ensure clean and stable amplification of the RF signal. The power coupler helps the amplifiers operate efficiently and transmits the signal to the industrial process equipment without significant distortion. Integrating the RF amplifier array and the coupler into a single system reduces the required footprint. This is particularly advantageous when the power converter needs to be integrated into compact control cabinets or space-constrained industrial plants. Close coupling between the RF amplifier array and the RF power coupler can help minimize transmission losses. This allows for greater utilization of available energy, which can improve the overall efficiency of the system.Since multiple RF amplifier arrays can be connected to the inputs of the RF power coupler, the system's power output can be flexibly adapted to the requirements of the specific application. This allows the power output to be increased or decreased depending on the process requirements. This design of an electrical power converter with an RF power coupler and multiple RF amplifier arrays can offer a versatile and efficient solution for demanding high-frequency industrial applications, with advantages in adaptability, energy efficiency, and integration.

[0063] In one aspect, the electrical power converter features a control device that controls the RF amplifier arrangements, in particular their phase relationship to each other, so that the power in the coupling unit is essentially fully coupled at the star point. This improves efficiency.

[0064] The development is explained in more detail below with reference to the advantageous embodiments shown in the figures. However, the development is not limited to any one of these embodiments. The figures show:

[0065] Fig. 1: an oblique view of a high-frequency power coupler;

[0066] Fig. 2: an oblique view of a high-frequency power coupler with housing parts removed;

[0067] Fig. 3: a cross-section through an oblique view of an RF power coupler without a housing;

[0068] Fig. 4: an oblique view of a high-frequency power coupler with housing parts removed;

[0069] Fig. 5: a cross-sectional view through part of a high-frequency power coupler;

[0070] Fig. 6: a schematic representation of an industrial process arrangement;

[0071] Fig. 7 shows a schematic representation of a coupling unit.

[0072] Fig. 8 shows a Smith chart and a corresponding equivalent circuit diagram of a power converter 2023P00598WG

[0073] 16

[0074] Fig. 1: shows an oblique view of a high-frequency power coupler 1. This RF power coupler is designed for coupling several RF input signals to a single RF output signal, for supplying RF power to an industrial process arrangement, preferably a plasma process arrangement, gas laser excitation, or heating arrangement. This RF power coupler comprises: a. several RF inputs 11, 12, 13, 14, 15, here configured as RF coaxial connectors, protruding from the housing 33; b. an RF output 7, here configured as an RF connector, also in a coaxial configuration; c. a coupling unit 19, which here is arranged on a coupling unit circuit board 49; d. an impedance matching line 20, which extends from the coupling unit 19 to the RF output 7 and has a predetermined length between these two ends.

[0075] The impedance matching line 20 has a branch line 50 with open-circuit termination, so that this impedance matching line 20 is designed to effect a predetermined impedance matching from the output of the coupling unit to the RF output 7,

[0076] The impedance matching line 20 has a predetermined length of less than Ä / 6 and greater than A / 10.

[0077] Fig. 1 further shows an upper mounting plate 23, a middle mounting plate 25 and a lower mounting plate 27, wherein the middle mounting plate 25 is arranged between the upper and the lower mounting plate and wherein the impedance matching line 20 is arranged between the upper mounting plate 23 and the middle mounting plate 25 and between the lower mounting plate 27 and the middle mounting plate 25.

[0078] The meandering shape of the impedance matching line 20 is clearly visible here.

[0079] Also shown are several fastening elements 35, in particular screws, with which, for example, the mounting plates 23, 25, 27 are connected to the housing 33.

[0080] Also shown are insulating layers 29, which are arranged between impedance matching line 20 and the mounting plates 23, 25, 27.

[0081] Also shown is a temperature sensor 37, which is arranged on one of the insulating layers 29. 2023P00598WG

[0082] 17

[0083] Also shown are several coolant channels 5, arranged in the upper mounting plate 23 and in the lower mounting plate 27 for the passage of coolant.

[0084] Also shown are two coolant connections 8 for supplying and discharging coolant. The coolant connections 8 are connected to the coolant channels 5.

[0085] Also shown is a control connection 36 for control and data lines, e.g. for the measured signal from the temperature sensor 37.

[0086] Also shown is a recess 31 which has the middle mounting plate 25 for the routing of the impedance matching line 20.

[0087] Also shown is a cylinder 32, which provides an electrical connection of the impedance matching line 20 between the two layers of the impedance matching line 20.

[0088] Also shown are shielding spring contacts 34. These can be used to improve the electromagnetic properties of the RF power coupler.

[0089] Not shown, but conceivable, is an arrangement in which the impedance matching line 20 is guided at the edge of the middle mounting plate 25.

[0090] Fig. 2: shows an oblique view of the high-frequency power coupler 1 from Fig. 1 with at least partially removed housing parts, and without the upper mounting plate 23, so that the impedance matching line 20 with the branch line 50 on the insulating layer 29 is more clearly visible.

[0091] In this and all subsequent figures, the same components have the same reference numbers.

[0092] Fig. 3 shows a cross-sectional view through the high-frequency power coupler 1 from Fig. 1 or Fig. 2 with at least some housing parts removed and without the upper mounting plate 23, so that the impedance matching line 20 with the branch line 50 on the insulating layer 29 is more clearly visible. The plane of the section passes through the lower mounting plate 27, the middle mounting plate 25, the insulating layer 29, the recess 31, the cylinder 32, and the impedance matching line 20. This clarifies the path of the impedance matching line 20. In particular, the transition from the position between the upper and middle mounting plates 23, 25 to the position between the lower and middle mounting plates 25, 27 by means of the recess 31 and the cylinder 32 is clearly visible. The cylinder 32 is made of metal, specifically copper. It serves to connect the impedance matching line 20 between the two layers.It is arranged insulated from the mounting plate. The mounting plate therefore has a recess 31 with a correspondingly larger diameter. Also visible is the coolant channel 5, which connects the two coolant connections 8 and is located in the lower mounting plate 27. A coolant 6, e.g., water, can be carried in this channel to dissipate the heat that may be generated by the impedance matching line 20 during operation. A coolant channel 5 can, of course, also be arranged in the upper and / or middle mounting plates 23, 25. In the present case, such a coolant channel 5 is indeed also provided in the upper mounting plate 23. However, the upper mounting plate 23 is not shown in this figure for the sake of clarity.

[0093] Fig. 4 shows an oblique view of the high-frequency power coupler 1 from Figs. 1-3 with at least some of the housing parts removed. In contrast to Fig. 3, the upper mounting plate 23 is shown here. Components that are not normally visible, such as the impedance matching line 20, the coolant channel 5, or the cylinder 32, are shown with dashed lines.

[0094] Fig. 5 shows a cross-sectional view through a portion of the high-frequency power coupler 1 from Figs. 1-4. The side view of the upper mounting plate 23, the middle mounting plate 25, and the lower mounting plate 27 is shown. Two insulating layers 29 are located between each of the mounting plates. The impedance matching line 20 is arranged between these insulating layers 29, thus running in two layers. The RF inputs 11, 12, 13, 14, and 15 are located on the same side of the housing 36 as the RF output 7. The impedance matching line 20 runs in a meandering path from the connection side of the housing to the opposite side, then changes position via the cylinder 32 in the recess 31, and in the other position also meanders back to the connection side of the housing 36. This design optimizes space utilization. The impedance matching line 20 runs on both sides of the middle mounting plate 25.

[0095] The figure also shows how the insulating layer 29 is arranged between the impedance matching line 20 and the middle mounting plate 25, also in the area of ​​the recess 31, for electrical insulation of the impedance matching line 20 from the middle mounting plate 25.

[0096] Fig. 6 shows a schematic representation of an industrial process arrangement 100. The industrial process arrangement 100 includes an electrical power converter 4 as part of the industrial process arrangement 100. This is a gas laser excitation with an impedance matching device 64 connected to the power converter 4. The electrical power converter 4 includes: a. An RF power coupler 1, as described in this disclosure, 2023P00598WG

[0097] 19 b. Several RF amplifier arrangements 62, each connected to one of the RF inputs 11 , 12, 13, 14, 15 of the high-frequency power coupler 1.

[0098] The RF output 7 of the RF power coupler 1 is connected to the gas laser excitation arrangement 63 via a high-power interconnect 74. The high-power interconnect 74 is preferably a coaxial interconnect. These are manufactured with fixed impedances, preferably 50 Ω. For this reason, among others, the preferred output impedance of the RF power coupler 1 is also set to 50 Ω. The RF power supplied by the power converter 4 is routed to an impedance matching device 64. This device typically has several reactances, such as inductance(s) or capacitance(s). These can each be partially or fully variable, i.e., adjustable, to match the input impedance of the load to the output impedance of the RF power coupler 1.

[0099] The gas laser excitation arrangement 63 has several discharge tubes 69 in which a plasma is generated using RF power. Upon recombination of the charged components of this plasma, the laser beam is produced by selecting a suitable gas, pressure, and mirror arrangement. This laser beam is then emitted at the laser outlet 68. Such a laser can be used in an EUV system. To generate and maintain the plasma in the discharge tubes 69, RF power is supplied to these tubes via electrodes. The RF power is transmitted from the impedance matching device 64 via a first connecting line 66, in particular an RF signal connecting line, to a first electrode arrangement 67, in particular an RF signal electrode arrangement.

[0100] The first connecting line 66 can have a first matching inductance 65, in particular an RF signal matching inductance, which can act as part of the impedance matching.

[0101] Opposite the first electrode arrangement 67, a second electrode arrangement 73, in particular a ground-side electrode arrangement, is arranged. This is connected to a ground terminal 72 via a second connecting line 70, in particular a ground-side connecting line. The second connecting line 70 can have an impedance matching inductance 71, in particular a ground-side impedance matching inductance, which can act as part of the impedance matching.

[0102] Between the first electrode arrangement 67 and the second electrode arrangement 73, an electric RF field can build up during operation, which is used for plasma excitation.

[0103] The housing 33 of the RF power coupler 1 is connected to a ground terminal 72. 2023P00598WG

[0104] 20

[0105] The housing of the gas laser excitation arrangement 63 is connected to a ground connection 72.

[0106] Fig. 7 shows a schematic representation of a coupling unit 19. The coupling unit 19 includes a coupling unit circuit board 49 on which the RF inputs 11, 12, 13, 14, 15 are arranged. These can be soldered to the coupling unit circuit board 49 as coaxial connectors. The coaxial connectors are shown in Figures 1 to 4. They protrude from the housing 33 in these figures.

[0107] The control connection 36 can also be located on the coupling unit circuit board 49. This is also shown in Figures 1 to 4. It also protrudes from the housing 33.

[0108] The RF inputs 11, 12, 13, 14, 15 are each connected to a star point 10 via connecting lines 41, 42, 43, 44, 45. The star point 10 is connected in the RF power coupler 1 to the first endpoint of the impedance matching line 20. The second endpoint of the impedance matching line 20 is connected to the RF output 7, as also shown in Figures 1 to 4.

[0109] The connecting lines 41, 42, 43, 44, 45 can each be interrupted by RF switching units 51, 52, 53, 53, 55. These RF switching units 51, 52, 53, 53, 55 can be configured, for example, as RF relays. Semiconductor-based switching units, such as PIN diodes or transistors, are also conceivable. These RF switching units 51, 52, 53, 53, 55 can be used to disconnect individual connections during operation. This can be helpful, for example, if one of the amplifier assemblies 62 needs to be replaced while the other amplifier assemblies 62 remain in operation. In semiconductor manufacturing, for example, in plasma generation for semiconductor processes or in EUV lithography, this can offer a significant advantage. The RF switching units 51, 52, 53, 55 can be controlled via signal paths connected to the control terminal 36. This can be done in particular via the coupling unit circuit board 49. This is shown in Fig.Figure 7 shows an example of the RF switching unit 51, 52.

[0110] Fig. 8 shows a Smith chart 80 and a corresponding equivalent circuit diagram of a power converter 4.

[0111] The RF amplifier arrangements 62 are shown here as RF signal sources 86, each with an output impedance 87. This output impedance 87 of an amplifier arrangement 62 is typically 50 Ω. An output impedance of 50 Ω corresponds to the industry standard for many high-frequency and amplifier systems. This facilitates the integration of the amplifier arrangement into existing systems, since many RF components, such as connectors, cables, and measuring instruments, are also designed for 50 Ω. This reduces unwanted reflections. The Smith chart 80 serves to illustrate the impedance matching by the RF power coupler 1. In the Smith diagram 80 and in the equivalent circuit diagram of the power converter 4, the impedance matching line input impedance 81, the impedance matching line output impedance with branch line 82 and impedance matching line output impedance without branch line 83 are shown.

[0112] The impedance matching effect of the individual components of the impedance matching line 20, divided into branch-line-free impedance matching line 20' and branch line 50, can be seen from the representation in the Smith diagram 80. The location of the respective measurable impedances 81, 82, and 83 can be identified from the representation in the equivalent circuit diagram of the power converter 4.

[0113] For example, the location of the impedance matching line to the input impedance 81 is also shown schematically in the lower equivalent circuit diagram of a power converter 4. Since five RF amplifier arrangements 62, each with an output impedance 87 of 50 Ω, are connected to the coupling unit 19, an impedance of 10 Ω is present. This can also be seen in the Smith chart 80.

[0114] The impedance matching line 20' without a branch line, i.e., the portion of the impedance matching line 20 excluding the branch line 50, is represented in the equivalent circuit diagram below by a transmission line symbol. The branch line 50 is also represented in the equivalent circuit diagram below by a transmission line symbol. The impedance transformation from the input impedance 81 of the impedance matching line to the output impedance without branch line 83 is performed by the impedance matching line 20' without a branch line. This can be significantly shortened here because the impedance transformation from the output impedance without branch line 83 to the output impedance with branch line 82 is performed very efficiently using this branch line 50.Overall, this significantly reduces the space required for the impedance matching line 20 compared to an arrangement without a branch line 50.

[0115] The features disclosed in the foregoing description, claims and drawings may be important for the realization of the invention in its various embodiments, both individually and in combination.

Claims

1. 22 Claims 1. High-frequency power coupler (1) for coupling several RF input signals to one RF output signal, for supplying RF power to an industrial process arrangement (1), preferably a plasma process arrangement, gas laser excitation or heating arrangement, wherein the RF power coupler (1) comprises: a. several RF inputs (11, 12, 13, 14, 15), b. one RF output (17), c. a coupling unit (19), d. an impedance matching line (20) extending from the coupling unit (19) to the RF output (17) and having a predetermined length between these two ends, e. wherein the impedance matching line (20) has a branch line (50) with open-circuit termination, such that this impedance matching line (20) is designed to effect a predetermined impedance matching from the output of the coupling unit (19) to the RF output (7), f. wherein the predetermined length is less than Ä / 6 and greater than Ä / 10.

2. RF power coupler according to claim 1, wherein the branch line (50) is designed with open-circuit termination in the form of a microstrip line.

3. RF power coupler according to one of the preceding claims, wherein the branch line (50) is connected closer to the RF output (17) than to the coupling unit (19), in particular directly in front of the RF output (17).

4. RF power coupler according to one of the preceding claims, wherein the branch line (50) is shorter than A / 20.

5. RF power coupler according to one of the preceding claims, wherein the branch line (50) is shorter than 60 cm.

6. RF power coupler according to one of the preceding claims, wherein the impedance matching line (20) is arranged planarly on an insulating layer (29) and in particular the branch line (50) is arranged on the same insulating layer (29). 2023P00598WG 23 7. RF power coupler according to one of the preceding claims, comprising an upper mounting plate (23), a middle mounting plate (25) and a lower mounting plate (27), wherein the middle mounting plate (25) is arranged between the upper and the lower mounting plate.

8. RF power coupler according to one of the preceding claims, wherein the impedance matching line (20) is arranged between the upper and middle mounting plates and between the lower and middle mounting plates.

9. RF power coupler according to one of the preceding claims, wherein the branch line is arranged between the upper and the middle mounting plate and / or between the lower and the middle mounting plate.

10. RF power coupler according to one of the preceding claims, wherein at least one of the mounting plates (23, 25, 27) is designed as a cooling plate with a channel for passing a cooling fluid.

11. RF power coupler according to one of the preceding claims, wherein one, in particular several, particularly preferably all mounting plate(s) (23, 25, 27) are connected to a constant potential, preferably to ground.

12. RF power coupler according to one of the preceding claims, wherein one, in particular several, particularly preferably all mounting plate(s) (23, 25, 27) are connectable to a metallic housing (37).

13. Electrical power converter (4) for an industrial process arrangement (100), preferably a plasma process arrangement, gas laser excitation or heating arrangement, comprising: a. An RF power coupler (1) according to one of the preceding claims, b. Several RF amplifier arrangements (62) designed to be connected to the RF inputs (11, 12, 13, 14, 15) of the RF power coupler (1).

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