Electronic devices and methods for cooling them

Abstract

An electronic device (10) for biasing a substrate in a plasma process, in particular a high-power (HP), high-voltage (HV) pulse power supply, the electronic device (10) comprises: - a plurality of electrical components (15) capable of generating heat when the device (10) is in use; - a container (12) in which at least a portion of the plurality of electrical components (15) are placed; and - an electrical solar heat transfer liquid (13), the electrical solar heat transfer liquid (13) being filled in the container (12), in direct contact with the electrical components (15), transferring heat away from the electrical components (15), and increasing the electrical solar radiation between the electrical components (15) compared to the electrical solar radiation of the air; the liquid (13) being sealed in a sealed volume (17), the sealed volume (17) being at least partially located inside the container (12) and maintained within a predetermined controlled pressure range.

Description

Technical Field

[0001] The present invention relates to an electronic device for a high-power (HP) pulse power supply for plasma processing, particularly as part thereof, comprising a plurality of electrical components that generate heat, - a container in which the plurality of electrical components are placed, - an electrically radiative heat transfer liquid filled in the container, directly contacting the electrical components, and transporting heat away from those electrical components,

[0002] HP pulse power supplies are often required for plasma processing equipment, for example for biasing a substrate, as disclosed in, for example, US10,474,184 (B2). In the case of such plasma processing equipment, one or more power supplies comprising an electronic device as described above are often required. Such power supplies and such electronic devices are known from, for example, EP4235738 (A1), which is hereby incorporated in its entirety by reference.

[0003] In the case of the present invention, high-power (HP) means a power of 2 kW or more, particularly 10 kW or more, during at least part of the pulse-on time. High voltage (HV) means a voltage of 1 kV or more, particularly 5 kV or more, and even more particularly 10 kV or more, during at least part of the pulse-on time. Pulse power supply means a power supply having a pulse frequency in the range of 50 Hz to 800 kHz.

[0004] In such HPs, the following problems arise with HV pulse power supplies: For several reasons related to the desired behavior of the plasma process, the power supply should often be placed as close to the plasma process as possible. Otherwise, excessive energy loss occurs in the power supply cable, and the cost of the power supply cable is incurred. Furthermore, the rise gradient of voltage and / or current can be adversely affected, for example, due to dielectric losses in the cable. The overall dimensions of such a power supply are severely limited because there is little available space near the plasma chamber. To keep the dimensions as small as possible, electronic components must be densely packed within the power supply. However, these small-dimensional requirements conflict with the requirements for high solar radiation resulting from high voltage, as well as the requirement for low capacitance of the power supply due to the fast rise times of voltage and current.

[0005] The "electric solar heat transfer liquid" must be non-conductive. Its insulating properties should be superior to those of air. "Air" means all kinds of ambient air in the typical environment of such electronic devices during manufacturing, maintenance, testing, and / or use. Such an electrical solar fluid allows for shorter creepage distances and / or shorter discharge distances than when air is used for insulation.

[0006] Possible liquids that may be used for cooling are disclosed, for example, in WO2021 / 008949(A1), which describes a fluorinated liquid that is a very effective heat transfer liquid.

[0007] However, it was found that such power supplies, which involved direct contact cooling with the described liquid, experienced unpredictable and random malfunctions. These malfunctions were the core of the research and investigation.

[0008] From this perspective, an object of the present invention is to disclose an improved electronic device and an improved cooling method for such an electronic device that reduces the problems described above. In particular, an improved electronic device suitable for high-power (HP) and high-voltage (HV) pulsed power supplies for plasma processing is disclosed. The overall dimensions should be kept as small as possible without compromising reliability.

[0009] Furthermore, methods for cooling such devices are also disclosed.

[0010] In one embodiment, the electrically charged solar heat transfer liquid is sealed within a sealed volume, which is at least partially located inside a container and maintained within a predetermined pressure range. This pressure range is to be adjusted. The pressure range refers to a range of pressure values, for example, 2 bar to 3 bar.

[0011] In one embodiment, the container is - The first volume filled with gas, - A second volume filled with an electrically charged solar heat transfer liquid, wherein there is no separation between the first volume and the second volume.

[0012] Here, a membrane is not required between the first and second volumes. This is possible, in particular, if the electrically solar heat transfer liquid has solubility in the gas within the first volume, and this solubility is high enough to compensate for the volume change in the second volume at a specified temperature range, which is the temperature range during the device's operation. In this way, the pressure rise within the container is limited.

[0013] In one embodiment, the container is - The first volume filled with gas, - A second volume filled with an electrically charged solar heat transfer liquid, - It comprises a membrane that separates a first volume from a second volume.

[0014] In one embodiment, the membrane is permeable to the gas in the direction from a second volume to a first volume, but not in the opposite direction.

[0015] In one embodiment, the device has the following volume, namely, -First volume, - Second volume, and - Includes a pressure control unit, particularly a gas pressure control unit, for controlling the pressure of one or more of a sealed volume.

[0016] Electrical solar heat transfer liquids can increase the electrical solar radiation between these electrical components compared to the electrical solar radiation of the air.

[0017] In one embodiment, this objective is achieved by sealing the electrosolar heat transfer liquid within the container such that the electrosolar heat transfer liquid does not come into contact with external gases outside the container during the operation of the electronic device, and the electrosolar heat transfer liquid is degassed before the start of operation.

[0018] "Degassed before operation begins" means removing dissolved gases from a liquid. Numerous methods exist for removing dissolved gases from a liquid, including reduced pressure, thermal control, membrane degassing, ultrasonic degassing, sparging with inert gases, and the addition of reducing agents. Therefore, liquids are degassed when the removal of dissolved gases from such liquids is intentionally performed before the operation of an electronic device begins. This can be done during the manufacturing of the electronic device and / or immediately before the start of one or each operation.

[0019] Unpredictable and random malfunctions have been found to be caused by factors such as the formation of bubbles in a liquid when it is heated during the operation of an electronic device. By reducing the formation of these bubbles, the frequency of such malfunctions can be reduced. Therefore, numerous attempts have been made to reduce this bubble formation. One successful attempt was to degas the liquid and prevent the dissolution of new gases during delivery, installation, and / or operation.

[0020] In one embodiment, the degassing of the liquid is performed during the manufacturing of the electronic device, before its delivery, and before its use. Therefore, the manufacturer has complete control over the degassing process and can control the condition of the device before delivery and installation. Different conditions are possible for different applications or environmental factors such as ambient temperature to reduce manufacturing costs.

[0021] In one embodiment, an electronic device is configured such that a liquid can be degassed during maintenance and / or use of the electronic device. For such purposes, an inlet and outlet for the liquid may be attached to the container. These connections may be closable and sealable so that no gas or air from the outside can enter the container during the degassing procedure.

[0022] In one embodiment, the electronic device includes a degassing unit for removing gas from the liquid. Since such a degassing unit is connected to the container, degassing can occur even during operation. This can be an additional advantage in process areas where the reliability requirements for the electronic device are very high, or in process areas where the temperature and / or voltage between components are very high.

[0023] In one embodiment, the degassing unit comprises a housing having a liquid inlet, a liquid outlet, at least one porous membrane, and at least one gas outlet. Such a degassing unit may be useful for degassing during operation and / or maintenance.

[0024] In one embodiment, the degassing unit comprises a membrane containing a plurality of pores for removing gas from the liquid. Such a degassing unit may be useful in degassing during operation, and / or maintenance, and / or manufacturing.

[0025] In one embodiment, the degassing unit comprises a low-pressure source, particularly a vacuum source, connected to at least one gas outlet. Such a degassing unit can remove gas in a highly efficient manner.

[0026] In one aspect, the degassing unit includes a hollow fiber membrane array having a plurality of hollow fiber membranes coaxially disposed within a cartridge, a distribution tube, and a collection tube having baffles disposed therein to divert liquid. Such a degassing unit can remove gas in a very efficient manner.

[0027] In one aspect, an electronic device includes a liquid guiding device configured to guide an electro-solar heat transfer liquid in parallel along at least a portion of a plurality of electrical components such that a portion of the plurality of electrical components are cooled at the same temperature.

[0028] This has the great advantage that in such an electronic device, it is possible to reduce the electrical deviation of a part of the plurality of electrical components caused by the temperature difference between the components. This results in a much more stable electronic device.

[0029] There can be different solutions for the liquid guiding device, such as tubes, pumps, ventilators, etc. The important thing is that those solutions are capable of guiding the liquid in parallel across their electrical components to cool the electrical components at the same temperature.

[0030] In one aspect, an electronic device is configured as follows. a. A plurality of electrical components include semiconductor components, particularly transistors and / or diodes, connected in a series circuit, and this series circuit is configured to be connected to a high voltage of 1 kV or more during operation. b. The semiconductor components, particularly transistors and / or diodes, within the series circuit are connected such that the high voltage is divided among at least a portion of the semiconductor components during operation. c. The electronic device comprises a liquid induction device, which is configured to induce an electrically solar heat transfer liquid in parallel along at least some of the semiconductor components such that those semiconductor components are cooled to the same temperature.

[0031] In such electronic devices, particularly in the high-power, high-voltage pulsed power supplies mentioned above, it has been found that several switching elements need to be connected in series. Because these switching elements must switch very rapidly for the pulsed power supply, only semiconductor components are feasible. Transistors operating in switch mode are likely to be these semiconductor components.

[0032] However, such transistors have a limited maximum voltage across their connections and are often unsuitable for voltages above 1kV. One possible solution is to connect those semiconductor components, particularly transistors, so that high voltages are divided among at least some of them during operation. However, this only works if the circuit is well-balanced, which prevents the voltage in any of those semiconductor components from exceeding the limit of that component. Such balancing is a challenging design task. Even small deviations, perhaps small at the start, can lead to unbalances that increase due to self-reinforcing feedback. We have found that even cooling equipment has an effect on balancing. After research, we have recognized that cooling components in parallel by a method of cooling the components at the same temperature improves the effect on the overall balancing of those components.

[0033] Therefore, we decided to find a structure that includes a liquid induction device, configured to induce an electrically solar heat transfer liquid in parallel along at least some of those semiconductor components so that these semiconductor components are cooled to the same temperature.

[0034] As mentioned above, different solutions for liquid induction equipment can exist, such as tubes, pumps, and ventilators. The important thing is that these solutions are capable of inducing the liquid in parallel across their electrical components, thereby cooling the electrical components to the same temperature.

[0035] In one embodiment, the liquid induction device comprises several culverts within the PCB at a predetermined distance from the semiconductor components placed on the PCB so as to be cooled at the same temperature.

[0036] PCB refers to a printed circuit board on which electrical components can be placed and connected, or a similar carrier for electrical components.

[0037] In one embodiment, the transistor operates as a switching transistor for switching pulses for a high-voltage (HV) pulsed power supply. Examples and functions are described in detail, for example, EP4235738(A1).

[0038] In one embodiment, the liquid induction device comprises a volume on one side of the PCB or carrier for the electrical components through which a first pressure acts, and a volume on the other side of the PCB or carrier for the electrical components through which a second pressure acts, the PCB or carrier for the electrical components comprising a hole as a culvert for inducing liquid in parallel.

[0039] In one embodiment, the device comprises components that come into contact with the liquid and are configured to move fan blades or a pump rotor, at least some of which are made of a metal or other conductive material or are coated with a layer of a conductive material, particularly titanium nitrate.

[0040] In one embodiment, the device includes a fluctuation generator configured to move a liquid around the container in order to transfer heat from the electrical components.

[0041] In one embodiment, at least some of the electrical components are arranged to support natural convection in which the potential of the electrical components acts as a potential fluctuation generator.

[0042] In one embodiment, the fluctuation generator includes a stirrer or a pump.

[0043] In one embodiment, the liquid is configured as a liquid filled in a container, the container having a first volume above the liquid level of the liquid.

[0044] Furthermore, with respect to the method, the object of the present invention is achieved by a method for cooling an electronic device for biasing a substrate in a plasma process, particularly an HP pulse power supply, and the method is - The step of providing a container, - The step of arranging electrical components that generate heat when used in the container, - The step of filling the container with an electrically charged solar heat transfer liquid, - The steps include sealing and maintaining an electrically charged solar heat transfer liquid within a sealed volume, wherein this sealed volume is at least partially located inside a container, - The step of maintaining an electrically charged solar heat transfer liquid within a predetermined adjusted pressure range.

[0045] We found that bubbles in the liquid that appear during heating can cause several problems. Therefore, we found that the proposed use of such solarized liquids in gas / liquid equilibrium, as proposed by WO2021 / 008949(A1), may have adverse effects on the use of such power sources.

[0046] This invention solves this problem by constructing a high HP, HV pulsed power supply for biasing a substrate in a plasma process. This power supply operates with extremely high reliability in the plasma process.

[0047] According to a further embodiment of the present invention, any solar radiation component that comes into contact with a liquid and is configured to move fan blades or a pump rotor, etc., is made of a metal or other conductive material, or is coated with a layer of a conductive material. This reduces the amount of electrostatic discharge, thereby reducing the electrostatic force in the liquid and increasing the efficiency of contact between the solar radiation coolant and the component.

[0048] According to a further embodiment of the present invention, at least some of the electrical components are arranged to support natural convection, in which the potential of the electrical components acts as a potential fluctuation generator. From this viewpoint, a specialized pump unit can be avoided or arranged in a smaller form. Solar-irradiated liquids are sensitive to high gradients of electric fields and can be accelerated using a strong electric field, so this phenomenon can be used to move the liquid. Typically, the liquid is accelerated from the negative potential to the positive potential of the electric field. By using this phenomenon, natural convection can be obtained. To obtain natural convection, preferably the direction of the potential should be appropriately designed. Thus, mechanical pumps, fans, or agitators can be completely avoided, or the effect of such devices can also be enhanced by using natural convection.

[0049] According to a further embodiment of the present invention, the fluctuation generator is equipped with a stirrer or a pump. From this viewpoint, highly efficient gas removal can be obtained.

[0050] According to a further embodiment of the present invention, the liquid is configured as a liquid filled in a container, and the container contains a gas volume above the liquid level. It has been found that the gas solubility of the coolant depends on the pressure. Since the liquid expands with increasing temperature, some extra empty volume should be provided to allow for the volumetric expansion of the coolant. As the pressure increases, the gas solubility also increases. Therefore, more gas dissolves with increasing temperature. As a result, the pressure decreases and the gas solubility stabilizes at the highest level for a given pressure. Thus, the total volume of the coolant and gas in the container can be kept as small as possible.

[0051] According to a further embodiment of the present invention, the degassing unit comprises a membrane containing a plurality of pores for removing gas from a liquid. Using a membrane is highly effective in removing gas from a flowing liquid. The pores are typically micropores small enough to remove only the gas and not the liquid.

[0052] According to a further embodiment of the present invention, the gas removal effect can be further enhanced by using a vacuum source connected to at least one gas outlet.

[0053] According to a further embodiment of the present invention, the degassing unit comprises a hollow fiber membrane array having a plurality of hollow fiber membranes arranged coaxially within a cartridge, a distribution tube, and a collection tube having baffles arranged to bypass the liquid.

[0054] Such degassing units are sold by 3M under the trademark "Liqui-Cel". Such degassing units are specialized for removing gas from water. According to the present invention, such commercially available degassing units are used to remove gas from electrically solar heat transfer liquids.

[0055] According to a further embodiment of the method of the present invention, the liquid is circulated by natural convection, preferably supported by an electric field generated by at least some of the electrical components.

[0056] According to a further embodiment of this method, the liquid is circulated by a pump or agitator.

[0057] According to a further embodiment of the present invention, the gas is removed from the liquid using a porous membrane.

[0058] Furthermore, gas removal can be assisted by a vacuum to increase efficiency.

[0059] Furthermore, the electrically charged solar heat transfer liquid may be configured as a liquid filled in a container having a volume that extends above the top layer of the liquid.

[0060] All of these means help to improve the efficiency of the method according to the present invention.

[0061] The features described above and those described later can be used not only in a given combination, but also in different combinations or independently of each other, without departing from the scope of the present invention.

[0062] Further features and advantages of the present invention will become apparent upon reading the following description of preferred embodiments in conjunction with the accompanying drawings. [Brief explanation of the drawing]

[0063] [Figure 1A] A first embodiment of an electronic device is shown. [Figure 1B] Further embodiments of the electronic device are shown. [Figure 1C] Further embodiments of the electronic device are shown. [Figure 2] This chart shows the trend in pressure inside a container with gas above the volume of coolant and gas, as well as the trend in the temperature of the coolant over time. [Figure 3] This is a schematic partial perspective cross-sectional view of a conventional degassing unit used in the present invention. [Figure 4]Further embodiments of the electronic device are shown. [Figure 5] Further embodiments of the electronic device are shown. [Figure 6] Further embodiments of the electronic device are shown. [Figure 7] This shows one embodiment of a series circuit connected to a high voltage. [Figure 8] This shows a plasma processing system equipped with a plasma chamber.

[0064] Figure 1A shows a schematic diagram of one embodiment of the electronic device 10 according to the present invention.

[0065] Device 10 comprises a printed circuit board (PCB) 14 or equivalent carrier of electrical or electronic components 15. Various electrical or electronic components 15 are positioned on the PCB 14. These electrical or electronic components 15 may be one or more integrated circuits 66, particularly semiconductor-based, such as one or more transistors 60, diodes 66a, one or more resistors 62, one or more capacitors 63, one or more inductors and / or transformers 64a, 64b, or driver circuits for transistors 60. These are all components of the electronic device 10. In this embodiment, the entire PCB 14 and all electronic components 15 are positioned inside the container 12. This is not mandatory. This is possible here and in all other embodiments, and it is also possible that some of the components 15 are outside the container 12, as will be shown later in Figures 4 to 6.

[0066] The container 12 is filled with liquid 13. The liquid 13 is configured as a solar heat transfer liquid, for example, as disclosed by WO2021 / 008949(A1), which is incorporated herein by reference in whole.

[0067] The electronic device 10 can be any type of electronic device that requires high packaging density and direct liquid cooling. In particular, device 10 can be an HP, HV pulse power supply, such as those known from EP4235738(A1), for biasing a substrate, especially in plasma processes.

[0068] The electronic device 10 may be part of an HP, HV pulse power supply, particularly for biasing a substrate in a plasma process, and may be part of such a power supply that particularly requires cooling and solar radiation, such as a switching transistor, an HV transformer, a diode, and an attenuation circuit comprising inductive and / or resistors.

[0069] Since the container 12 can be sealed, no gas or liquid can leak. The gas solubility of the coolant can be controlled by the pressure of the liquid 13. The liquid expands as the temperature rises. Therefore, some extra volume 31 is needed above the top 29 of the liquid 13, filled with a compressible medium such as gas, in order to allow for a second increase in the volume 35 of the liquid 13.

[0070] The electrically charged solar heat transfer liquid 13 is sealed within a sealed volume 17, which is at least partially located inside the container 12 and maintained within a predetermined controlled pressure range.

[0071] The ratio of the volume of liquid 13 to the first volume 31 of the compressible medium, and the pressure at a specified temperature, are selected in a preferred manner, in which case, as the pressure increases, the gas solubility also increases. Thus, more gas dissolves in liquid 13. As a result, the pressure in the container decreases, and the gas solubility stabilizes at the highest level relative to the current pressure.

[0072] In Figure 2, a coolant 13 is present inside the container 12. The pressure trend in the gas volume 31 above it is shown by the pressure line 30, and the temperature trend of the coolant over time is shown by the temperature line 32. Since both lines 30 and 32 are time-series lines, the horizontal axis is the time axis. The right axis shows the temperature value on a scale of °C. The left axis shows the differential pressure value on a scale of °C.

[0073] This phenomenon can be explained below using the graph in Figure 2. By using a coolant 13 with high gas solubility, the volume expansion of the container 12 can be reduced, and the volume change due to temperature can be compensated for. On the other hand, in order to avoid thermal expansion of the liquid 13, the volume change of the container 12 containing the coolant 13 and gas is kept as small as possible.

[0074] Figure 1B shows a further embodiment of the electronic device 10. Compared to the device 10 in Figure 1A, a fluctuation generator 24, specifically a pump, is connected to the container 12. Liquid is then supplied back into the container 12 from the fluctuation generator 24 through the liquid line 26.

[0075] Compared to device 10 in Figure 1A, the film 76 is located between the first volume 31 and the second volume 35. This is not essential here and is shown simply to illustrate the possibility of the combination of features described above.

[0076] Figure 1C shows a further embodiment of the electronic device 10. Compared to the device 10 in Figure 1A, a fluctuation generator 24 and a degassing unit 16 are used to remove gas from the liquid 13 when the coolant is poured onto the device. In the shown device, the degassing unit 16 is located externally for high efficiency and easy access. After degassing the liquid 13, the degassing unit 16 can be disconnected or remain in a stopped state, as shown in Figures 1A and 1B.

[0077] The degassing unit 16 comprises a housing 19 in which a porous membrane 18 is arranged. The liquid 13 from the container 12 is drawn into the inlet port 20 of the degassing unit and is forcibly discharged through the outlet port by a fluctuation generator 24, in particular a pump. The gas is removed by the porous membrane 18 and discharged through the gas outlet port. Gas removal is usually assisted by an external vacuum source 27.

[0078] Container 12 is filled with liquid 13 such that a small volume of gas 31 remains above the liquid. The membrane 76 is an element that separates the liquid and the gas.

[0079] The membrane 76 is used to separate the coolant from the gas and to prevent the gas 31 from entering the degassed liquid 13. Such a design leads to highly efficient gas removal from the liquid 13.

[0080] Figure 3 shows a suitable high-efficiency degassing unit, which is commercially available from 3M under the trademark "Liqui-CEL" and is shown collectively by reference number 34. While this degassing unit is specialized for removing gas from water, according to the present invention it is used to remove gas from an electrically charged solar heat transfer liquid 13.

[0081] In the explanation of Figure 3 below, the same reference number is used for similar parts as before.

[0082] The degassing unit 34 comprises a housing 19 containing a cartridge 38. A liquid inlet port 20 is provided at the first end of the housing 19, and an outlet port 22 is provided at the second end.

[0083] A gas / vacuum port 36 is further located at the first end, and a gas outlet port 28 is located at the second end. The liquid travels from the inlet port 20 through the central distribution tube 42 and is distributed radially into a hollow fiber membrane array 48 consisting of multiple hollow fiber membranes 46 arranged coaxially within the cartridge 38.

[0084] A central baffle 40 is present to deflect outwards and improve efficiency. On the other side of the baffle 40 is a central collection tube 44 for collecting the gas-removed liquid discharged from the degassing unit 34 through the outlet port 22.

[0085] A magnified view of a portion of the hollow fiber membrane is shown and is represented by reference numeral 46. Magnified micropores within membrane 46 are indicated by reference numeral 50. The hollow fiber membrane array is shown magnified by a safety device 48.

[0086] Figures 4, 5, and 6 show three different embodiments of the electronic device 10. The electronic device 10 comprises a container 12, which includes a heat transfer liquid 13, a PCB 14, a circulation device 80, and an air control system 74.

[0087] The container 12 is filled with heat transfer liquid 13. The PCB 14 is placed inside the container 12 and surrounded by the heat transfer liquid 13. Furthermore, the PCB 14 extends outwards from both sides of the container 12.

[0088] PCB14 comprises various components. These components include a transistor 60, a heat sink 61, a resistor 62, a capacitance 63, inductors 64a and 64b, a diode 66a, and a driver 66. The driver 66 of PCB14 may be located outside the container 12 on PCB14. In this way, and therefore, the driver is not surrounded by the heat transfer fluid 13. The remaining components are located inside the container 12 on PCB14 and are therefore surrounded by the heat transfer fluid 13. Inductors 64a and 64b are shown in two different embodiments. Each heat sink 61 is located on the transistor 60 and has multiple pins. PCB14 further comprises several culverts 65. These culverts 65 are designed to allow the heat transfer fluid 13 to flow through them. As a result, the heat transfer fluid 13 can flow through PCB14, so that the same heat transfer fluid 13 is present above and below PCB14. For reasons of clarity, only one of the different components is provided with a reference number. However, the remaining components can also be assigned through the same appearance of the same components.

[0089] The electronic device 10 includes a liquid induction device 95, which is configured to guide an electrical solar heat transfer liquid 13 along at least some of the multiple electrical components 15 such that some of the multiple electrical components 15 are cooled at the same temperature.

[0090] As described above, different solutions for liquid induction devices95 can exist, such as tubes, pumps, ventilators, etc. The important thing is that these solutions are capable of inducing the liquid in parallel across their electrical components and cooling the electrical components to the same temperature.

[0091] One possible solution is for the liquid induction device to consist of a volume on one side of the PCB 14 under a first pressure and a volume on the other side of the PCB 14 under a second pressure, with the PCB having holes as culverts 65 for guiding the liquid in parallel.

[0092] The components described and illustrated here are an example of a PCB 14 assembly. PCB 14 may also be equipped with other components, such as diode 66a.

[0093] The circulation device 80 of the container 12 comprises a heat transfer liquid outlet 67, a heat transfer liquid inlet 68, a heat transfer liquid pump 70, and a heat transfer liquid conduit 69. When the heat transfer liquid 13 is heated, the heated heat transfer liquid rises upward inside the container 12. The heat transfer liquid 13 that has risen upward then reaches the circulation device 80 via the heat transfer liquid outlet 67, where it can return to the lower region of the container 12 through the heat transfer liquid pump 70, the heat transfer liquid conduit 69, and the heat transfer liquid inlet 68. The heat transfer liquid 13 can be cooled by other devices within the circulation device 80. Thus, as a whole, the circulation device 80 ensures the circulation of the heat transfer liquid 13 within the container 12.

[0094] As indicated by arrow 87, the heat transfer liquid 13 flows through the culvert 65 to cool several components, including the transistor 60, in parallel, so that they are cooled to the same temperature.

[0095] The heat transfer liquid 13 expands when heated, and therefore the pressure inside the container 12 increases. The container 12 has an air control system 74 that counteracts this pressure increase. The purpose of this air control system 74 is to regulate the pressure inside the container 12.

[0096] For this purpose, the air control system 74 in Figure 4 comprises a membrane 76, a gas 75, a pump device 72, and a gas pressure control unit 73. The membrane 76 is made of an elastic material and is located above the PCB 14 in the container 12. The membrane 76 is impermeable to the heat transfer liquid 13. With respect to the gas 75, the membrane 76 may be permeable from one side, i.e., from bottom to top. The gas 75 of the air control system 74 is located above the membrane 76 in the container 12. Due to the unidirectional gas permeability of the membrane 76, unwanted gas in the heat transfer liquid 13 can pass through the membrane 76 to the outside of the heat transfer liquid 13. As a result, the impact on the function of the heat transfer liquid 13 may be reduced.

[0097] When the heat transfer liquid 13 expands, the membrane 76 is pushed upward, the volume of gas 75 in the container 12 does not change, and the pressure inside the container 12 increases. However, the volume of gas 75 in the container 12 can be increased or decreased via the pump device 72 and the gas pressure control unit 73. The pump device 72 and the gas pressure control unit 73 are connected to the container 12 via the gas outlet 71.

[0098] Therefore, overall, the air control system 74 can increase or decrease the pressure inside the container 12 by increasing or decreasing the volume of gas 75 inside the container 12.

[0099] In Figures 5 and 6, the air control system 74 includes a cylinder 78, a piston 77, gas 75, a pump device 72 (not shown), and a gas pressure control unit 73 (not shown).

[0100] Basically, the air control system 74 here has the same functions and even the same capabilities as the air control system 74 shown in Figure 4.

[0101] The only difference is that the air control system 74 is designed in the form of a cylinder 78. The gas 75 of the air control system 74, which regulates the pressure inside the vessel 12, is located above the piston 77 in the cylinder 78 and not inside the vessel 12. The piston 77 acts as a membrane 76 and can move up and down through the volume of gas 75 located inside the cylinder 78 to change the pressure inside the vessel 12. A pump device 72 and a gas pressure control unit 73 may be located at the top of the cylinder 78 (not shown).

[0102] In Figure 5, the cylinder 78 is introduced into the container 12. Therefore, the heat transfer liquid 13 in the container 12 can enter the cylinder 78 through the open lower side of the cylinder 78.

[0103] In Figure 6, the cylinder 78 is located outside the container 12 and is connected to the container 12 via a cylinder conduit 79. The heat transfer liquid 13 of the container 12 can enter the cylinder 78 via the cylinder conduit 79. The cylinder 78 may be made of the same material as the container 12.

[0104] Figure 7 shows one embodiment of a series circuit 89 configured so that the HV is connected to a high voltage 83 of 1 kV or more during operation. This HV 83 between connection point 81 and connection point 82 can be established by a series of low-power generators (LP generators) 94, 96, 98 connected in series.

[0105] The series circuit 89 comprises semiconductor components 84, particularly a transistor 60 and / or a diode 66a, each connected in series.

[0106] Further details and functions relating to such circuits are described in EP4235738(A1). The embodiment of the series circuit 89 shown in Figure 7 is only one of several possible embodiments. Several further embodiments are described, for example, in EP4235738(A1).

[0107] Figure 8 shows a plasma processing system comprising a plasma chamber 100 in which plasma 101 is established within a plasma space. Such or similar systems are also shown and described, for example, in EP4235738(A1). Device 10 of this description is designed for such or similar systems. An upper electrode 103 may be positioned within the plasma chamber. A gas inlet and / or outlet, in particular a gas supply pipe 104, may be placed inside the plasma chamber 100 from the outside and, in particular, connected to the electrode 103. A substrate 102, in particular a semiconductor wafer, may be placed on a support 105 with a substrate holder inside the plasma chamber 100. During use, the substrate 102 may be processed by the plasma 101 in processes such as etching, ashing, or deposition, in particular atomic layer deposition. The etching process can be very difficult when the ratio of the diameter to the length of the etched hole is very low, e.g., less than 1 / 100, as is often required in deep etching. The conductive electrode 106 may be placed inside the plasma chamber 100, particularly near the substrate 102, for example, around the substrate 102. This conductive electrode 106 may be an edge ring, which may also be called a focal ring. This conductive electrode 106 may be connected to a first power supply 114 via a first connecting line 115. The first power supply 114 may be a DC pulse power supply, in particular, the pulses may have different lengths, different amplitudes, and shapes, for example, as shown in Figure 2 of US10,474,184(B2).

[0108] By controlling the first power supply 114, the conductive electrode 106 may be additionally or alternatively used as a control unit for ion energy and / or ion acceleration direction, as also described in US10,474,184(B2). The first radio frequency (RF) power supply 118 may be electrically connected to the support 105 via the first power supply rod 119, the first matching unit 116, and the first connection unit 117. The second radio frequency (RF) power supply 108 may be electrically connected to the upper electrode 103 via the second power supply rod 109, the second matching unit 110, and the second connection unit 111. The electrode 107 may be positioned within or near the support 105 and may also be electrically connected to the second power supply 112 via the second connection line 113. The second power supply 112 may be a DC pulse power supply, in particular, the pulses may be of different lengths, different amplitudes, and shapes, as shown, for example, in Figure 2 of US10,474,184(B2). The substrate 102 can be fixed to the support 105 via an electrode 107 which can function as an electrostatic chuck. The electrode 107 may, additionally or alternatively, be used as a control for ion energy and / or ion acceleration direction by the control unit of the second power supply 112, as described in US10,474,184(B2).

[0109] Several plasma treatment applications, such as etching or layer deposition, require high-voltage (HV), high-frequency (HF), rectangular, asymmetrical pulsed voltage sources. Often, especially when high-frequency operation is required, the voltage values ​​far exceed the voltage handling capabilities of individual semiconductor switches.

[0110] Some plasma applications require not only pulsation but also amplitude variation between pulses. Some plasma applications require a source to deliver high peak currents to achieve short voltage transition times. Most plasma applications involve loads with capacitive components. Significant power losses are associated with the pulse-by-pulse charging and discharging process of this load capacitance. Some plasma applications require pulse shapes such as those shown in Figure 2 of US10,474,184(B2).

[0111] The power supplies 104, 112, 114, and 118 described may all include an electronic device 10 as described in this patent application.

[0112] In the case of HV, a series connection of such switches is one possible solution. A series connection requires a means of voltage balancing. These voltage balancing means are not easily implemented, especially in RF operation. Even if cleverly modified in a series connection, it can lead to imbalance, which often results in self-enhancement and even system degradation. We have found that such effects occur even with a cooling system that cools the series-connected switches in series rather than in parallel.

Claims

1. An electronic device (10) particularly as part of a high-power (HP), high-voltage (HV) pulse power supply for plasma processing, and especially for biasing a substrate in a plasma process, wherein the electronic device (10) is - A plurality of electrical components (15) capable of generating heat when the electronic device (10) is in use, - A container (12) in which at least some of the plurality of electrical components (15) are placed, - The container (12) is filled with an electrical solar heat transfer liquid (13) that is in direct contact with the electrical components (15) and transports heat away from these electrical components (15), The device (10) is characterized in that the electrically charged solar heat transfer liquid (13) is sealed within a sealed volume (17), and this sealed volume (17) is at least partially located inside the container (12) and maintained within a predetermined adjusted pressure range.

2. The container (12) is - The first volume (31) filled with gas, - A second volume (35) filled with the electrically charged solar heat transfer liquid (13), the device according to claim 1, characterized in that there is no separation between the first volume and the second volume.

3. The device according to claim 1 or 2, characterized in that the electrically solar heat transfer liquid (13) has a solubility of the gas in the first volume (31) that is sufficiently high to compensate for the volume change of the second volume (35) at a temperature within a specified temperature range which is the temperature range during use of the device (10).

4. The container (12) is - The first volume (31) filled with gas, - The second volume (35) filled with the aforementioned electrically charged solar heat transfer liquid (13), - The device according to any one of claims 1 to 3, characterized by comprising a membrane (76) that separates the first volume (31) and the second volume (35).

5. The device according to claim 4, characterized in that the membrane (76) is permeable to gas in the direction from the second volume (35) to the first volume (31), but not in the opposite direction.

6. The device (10) has the following volume: - The first volume (31), - The second volume (35), and / or - The device according to claim 4 or 5, further comprising a pressure control unit, in particular a gas pressure control unit (73), for controlling the pressure of one or more of the sealed volumes (17).

7. - The device according to any one of claims 1 to 6, characterized in that the electrically charged solar heat transfer liquid (13) is sealed inside the container (12) such that the electrically charged solar heat transfer liquid (13) does not come into contact with an external gas outside the container (12) during the operation of the electronic device, and the electrically charged solar heat transfer liquid (13) is degassed before the start of operation.

8. The device according to any one of claims 1 to 7, characterized in that the degassing of the liquid (13) is performed during the manufacture of the electronic device (13) before delivery and before use, and / or the electronic device (10) is configured such that the degassing of the liquid (13) can be performed during maintenance and / or use of the electronic device (10).

9. The device according to any one of claims 1 to 8, characterized in that the electronic device (10) further comprises a degassing unit (16, 34) for removing gas from the liquid (13).

10. a. The device according to any one of claims 1 to 9, wherein the electronic device (10) comprises a liquid induction device (95), and the liquid induction device (95) is configured to induce the electrical solar heat transfer liquid (13) along the portion of the plurality of electrical components (15) such that at least a portion of the plurality of electrical components (15) are cooled at the same temperature.

11. a. The plurality of electrical components (15) comprises semiconductor components (84, 86, 88), particularly transistors (60) and / or diodes (66a), connected to a series circuit (89), and this series circuit (89) is configured to be connected to a high voltage of 1 kV or more during operation. b. The semiconductor components (84, 86, 88) in the series circuit (89), particularly the transistor (60) and / or diode (66a), are connected in such a manner that, during operation, the high voltage is divided among at least some of the semiconductor components (84, 86, 88). c. The device according to any one of claims 1 to 10, wherein the electronic device (10) comprises a liquid induction device (95), and the liquid induction device (95) is configured to induce the electrically solar heat transfer liquid (13) in parallel along at least a portion of the semiconductor components (84, 86, 88) such that the semiconductor components (84, 86, 88) are cooled at the same temperature.

12. The device according to claim 10 or 11, characterized in that the liquid induction device (95) comprises several culverts (65) within the PCB (14) at a predetermined distance from the semiconductor components placed on the PCB (14) so ​​as to be cooled at the same temperature.

13. The device according to any one of claims 1 to 12, wherein the device (10) comprises components that come into contact with the liquid (13) and are configured to move fan blades or a pump rotor, and at least some of these components are made of a metal or other conductive material, or are coated with a layer of a conductive material, particularly titanium nitrate.

14. The device according to any one of claims 1 to 13, characterized in that the liquid (13) is configured as a liquid filled in the container (12), and the container (12) has a gas volume (31) above the liquid level (29) of the liquid.

15. A method for cooling a plurality of heat-generating electrical components (15), particularly an electronic device (10) equipped with a high-power (HP) pulsed power supply for biasing a substrate in a plasma process, wherein the method is - The step of providing a container (12), - The step of placing the electrical components (15) inside the container (12), - A step of filling the container (12) with an electrically charged solar heat transfer liquid (13), - The steps include sealing and maintaining the electrically charged solar heat transfer liquid (13) within a sealed volume (17), and ensuring that this sealed volume (17) is at least partially positioned inside the container (12), A method comprising the step of maintaining the electrically charged solar heat transfer liquid (13) within a predetermined adjusted pressure range.

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