Pressure control butterfly valve with self-cleaning function and plasma processing equipment

Abstract

The application relates to the technical field of semiconductor equipment, in particular to a pressure control butterfly valve with a self-cleaning function and a plasma processing equipment, which comprises a valve shell, a valve plate, a magnetic field generating piece, a by-product detecting piece and a control piece; the valve plate is rotationally arranged in the inner cavity of the valve shell and is made of metal material; the valve shell is made of insulating material; a gap for adjusting the opening degree of the butterfly valve is formed between the circumferential outer wall of the valve plate and the inner side wall of the valve shell; the magnetic field generating piece is arranged on the inner side wall of the valve shell; the magnetic field generating piece is connected with an alternating power supply and generates an alternating magnetic field when alternating current is input, and the magnetic induction lines of the alternating magnetic field pass through the valve plate; the detecting end of the by-product detecting piece faces the valve plate; the control piece is connected with the by-product detecting piece and the magnetic field generating piece; the application utilizes the electromagnetic induction principle, generates the alternating magnetic field through the magnetic field generating piece, directly generates eddy current in the valve plate to spontaneously heat, has high energy efficiency, and can quickly remove the by-products attached to the surface of the valve plate.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor manufacturing equipment, in particular to a pressure control butterfly valve with self-cleaning function and a plasma processing equipment. BACKGROUND

[0002] In the plasma processing equipment of semiconductor manufacturing process, the pressure control butterfly valve is a key component for maintaining the vacuum pressure of the process chamber. After long-term use (such as after processing 1000 wafers), the by-products of the process gas will gradually deposit on the surface of the movable valve plate. These deposits will change the physical properties of the valve plate, not only affecting the stability of pressure control, but also affecting the opening of the movable valve plate when the deposits reach a certain thickness, causing the movable valve plate to be stuck, causing the equipment to be down, and requiring a vacuum to be broken for maintenance, which seriously affects the production efficiency.

[0003] In order to alleviate this problem, the prior art usually adopts the method of wrapping heating elements (such as heating foam) on the outside of the exhaust pipeline and the valve to reduce the condensation of by-products on the valve plate. However, this method has limitations: the heat is conducted from the outside to the inside, which cannot effectively and directly heat the core movable valve plate itself, and the cleaning effect is poor; at the same time, in order to avoid the risk of sticking caused by the large temperature difference between the valve body and the valve plate and uneven expansion, the external heating temperature is strictly limited at a low level, which further restricts the cleaning efficiency. Therefore, a structure for efficiently cleaning the by-products on the movable valve plate and preventing the movable valve plate from being stuck is urgently needed. SUMMARY

[0004] The purpose of the present application is to provide a pressure control butterfly valve with self-cleaning function and a plasma processing equipment, which effectively prevents the valve plate from being stuck, ensures the precision of pressure control, improves the operation reliability and production efficiency of the plasma processing equipment, and avoids the production interruption caused by unplanned downtime.

[0005] To achieve the above purpose, the present application provides a pressure control butterfly valve with self-cleaning function, which comprises a valve housing, a valve plate, a magnetic field generating element, a by-product detecting element and a control element.

[0006] The valve plate is rotatably arranged in the inner cavity of the valve housing and made of metal material, the valve housing is made of insulating material, and the gap between the circumferential outer wall of the valve plate and the inner side wall of the valve housing can adjust the opening of the butterfly valve, and

[0007] The magnetic field generating element is arranged on the inner side wall of the valve housing and has a spacing between the valve plate, the magnetic field generating element is connected with an alternating power source and generates an alternating magnetic field with magnetic induction lines passing through the valve plate when an alternating current is input;

[0008] The detection end of the by-product detection piece faces the valve plate for real-time acquisition of by-product deposition information deposited on the valve plate;

[0009] The control piece is connected with the by-product detection piece and the magnetic field generating piece, and the control piece controls the magnetic field generating piece to generate an alternating magnetic field by energization, so that the valve plate generates eddy current and self-heats according to electromagnetic induction effect, to remove the by-products deposited on the valve plate.

[0010] Optionally, the size of the gap in the radial direction of the valve housing is less than or equal to 0.2 mm.

[0011] Optionally, the number of the by-product detection pieces is provided as several, and the several by-product detection pieces are divided into a first group, a second group and a third group, the detection end of the by-product detection piece in the first group faces the top end surface of the valve plate, the detection end of the by-product detection piece in the second group faces the bottom end surface of the valve plate, and the detection end of the by-product detection piece in the third group faces the circumferential wall surface of the valve plate.

[0012] Optionally, the magnetic field generating piece includes several straight wires;

[0013] The straight wires are arranged along the axial direction of the valve housing, and several straight wires are arranged equidistantly along the circumference on the inner side wall of the valve housing to generate an alternating magnetic field covering at least part of the valve plate when energized.

[0014] And / or the straight wires are arranged along the radial direction of the valve housing, and several straight wires are arranged on one side of the radial surface of the air inlet end of the valve housing and / or one side of the radial surface of the air outlet end of the valve housing.

[0015] Optionally, the magnetic field generating piece includes several annular wires, the annular wires are arranged along the circumferential direction of the valve housing, and several annular wires are arranged along the axial direction on the inner side wall of the valve housing to generate magnetic induction lines penetrating into the valve plate from the top end surface or the bottom end surface of the valve plate when energized, and several annular wires are arranged coaxially with the valve housing and / or arranged non-coaxially with the valve housing.

[0016] Optionally, the magnetic field generating piece includes a spiral coil, the spiral coil is arranged in a spiral shape along the axial direction of the valve housing and arranged on the inner side wall of the valve housing, to generate magnetic induction lines penetrating into the valve plate from the top end surface or the bottom end surface of the valve plate when energized.

[0017] Optionally, the number of the spiral coils is provided as N, N is a positive integer greater than or equal to 2;

[0018] N number of said spiral coils are arranged along the axial direction of said valve housing in sequence, and the central axis of each of said spiral coils coincides with the central axis of said valve housing, so that the magnetic flux generated by said N number of spiral coils passes through the same position of said valve plate when energized;

[0019] and / or N number of said spiral coils are arranged along the radial direction of said valve housing in sequence and away from the central axis of said valve housing, and the central axis of each of said spiral coils coincides or does not coincide with the central axis of said valve housing.

[0020] Optionally, the pitch of said spiral coils decreases in sequence along the axial direction of said valve housing from the area close to the rotation axis of said valve plate to the edge area of said valve plate, so that the number of turns of said spiral coils located at the edge area of said valve plate is denser than that of said spiral coils located at the rotation axis of said valve plate, thereby generating a stronger alternating magnetic field at the edge area of said valve plate than at the rotation axis of said valve plate.

[0021] Optionally, said magnetic field generating member comprises at least one of a plurality of annular wires and a plurality of spiral coils, said annular wires and said spiral coils each comprise an inner coil and an outer coil along the radial direction of said valve housing, and the winding direction of said inner coil and said outer coil is opposite, so that the alternating magnetic fields generated by said inner coil and said outer coil are superimposed in the axial direction and constrained in the radial direction when energized, wherein said inner coil is arranged close to the central axis of said valve housing.

[0022] Optionally, said magnetic field generating member comprises at least one of a plurality of straight wires, a plurality of annular wires and a plurality of spiral coils, each of said straight wires, said annular wires and said spiral coils is respectively and independently connected to said alternating power source, so as to generate a selectively heated alternating magnetic field in different areas of said valve plate.

[0023] Optionally, the inner side wall of said valve housing is recessed with a recessed portion, and said magnetic field generating member is arranged in said recessed portion;

[0024] said magnetic field generating member is embedded in said recessed portion;

[0025] or part of said magnetic field generating member protrudes out of said recessed portion, and the part of said magnetic field generating member protruding out of said recessed portion has a radial dimension of said valve housing less than or equal to 0.05mm.

[0026] Optionally, the inner side wall of said valve housing is provided with a plurality of flow guide grooves extending in the axial direction at equal intervals along the circumferential direction, so as to guide the gas to flow from the gas inlet end to the gas outlet end of said valve housing, thereby reducing the vortex effect of the gas.

[0027] Optionally, a plurality of temperature sensors are arranged in the valve housing, and the temperature sensors are respectively directed to the top end face, the bottom end face and the circumferential side wall of the valve plate to monitor the temperature of the top end face, the bottom end face and the circumferential side wall of the valve plate in real time, and the temperature sensors are connected with the control member.

[0028] Optionally, the valve plate is internally provided with a hollow cavity, and the hollow cavity is filled with phase change energy storage materials to maintain the temperature of the valve plate after power failure by using the heat storage characteristics of the phase change energy storage materials.

[0029] Optionally, the pressure control butterfly valve with the self-cleaning function further comprises a valve controller and a connecting member, the valve controller is arranged outside the valve housing, and the connecting member is arranged on the valve housing and used to connect the valve controller and the valve plate to conduct the driving force of the valve controller to rotate the valve plate in the valve housing, so as to adjust the opening degree of the butterfly valve.

[0030] To achieve the above-mentioned purpose, the application further provides a plasma processing equipment comprising a process chamber, a gas exhaust pump, a gas exhaust on-off valve, a plasma generating member and the pressure control butterfly valve with the self-cleaning function, the process chamber and the gas exhaust pump are connected through a pipeline, the pressure control butterfly valve with the self-cleaning function is arranged on the pipeline, the gas exhaust on-off valve is arranged between the pressure control butterfly valve with the self-cleaning function and the gas exhaust pump, and the plasma generating member is arranged in the process chamber.

[0031] The application has the following beneficial effects:

[0032] The application utilizes the electromagnetic induction principle, generates an alternating magnetic field by the magnetic field generating member to directly generate eddy current in the valve plate to generate heat spontaneously, the "from inside to outside" heating mechanism has high energy efficiency and can quickly remove the by-products attached to the surface of the valve plate; at the same time, the real-time monitoring of the by-product detecting member and the intelligent judgment of the control member change the equipment maintenance mode from passive or regular intervention to predictive maintenance according to needs, so as to effectively prevent the valve plate from being stuck, ensure the pressure control precision, significantly improve the operation reliability and production efficiency of the plasma processing equipment, and completely avoid the production interruption caused by unplanned downtime. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 FIG. 1 is a structural schematic diagram of a plasma processing equipment according to an embodiment of the application;

[0034] Figure 2 FIG. 3 is a structural schematic diagram of a valve housing in a pressure control butterfly valve with a self-cleaning function according to an embodiment of the application;

[0035] Figure 3Structure diagram of valve housing, magnetic field generating part and valve plate in self-cleaning pressure control butterfly valve of the embodiment of the present application Figure 1 ;

[0036] Figure 4 Structure diagram of valve housing, magnetic field generating part and valve plate in self-cleaning pressure control butterfly valve of the embodiment of the present application Figure 2 ;

[0037] Figure 5 Structure diagram of inner coil and outer coil in self-cleaning pressure control butterfly valve of the embodiment of the present application

[0038] Figure 6 Structure diagram of valve plate in self-cleaning pressure control butterfly valve of the embodiment of the present application

[0039] Explanation of reference signs:

[0040] 1, valve housing; 2, valve plate; 3, gap; 4, magnetic field generating part; 41, straight wire; 42, annular wire; 421, inner coil; 422, outer coil; 6, flow guide groove; 7, controller; 8, connecting piece; 9, air extraction pump; 10, air extraction on-off valve; 11, plasma generating part; 12, process chamber. DETAILED DESCRIPTION

[0041] In order to make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application. Unless otherwise defined, the technical terms or scientific terms used herein should be understood as the common meanings by those skilled in the art. The similar words such as “comprise” used herein mean that the elements or objects before the words cover the elements or objects listed after the words and their equivalents, without excluding other elements or objects.

[0042] In view of the problems in the prior art, the embodiments of the present application provide a pressure control butterfly valve with self-cleaning function, as shown in Figure 1 and Figure 2 , which comprises a valve housing 1, a valve plate 2, a magnetic field generating part 4, a by-product detecting part and a control part.

[0043] In one embodiment, as shown in Figure 1 and Figure 2 , the valve plate 2 is provided with a plurality of flow guide grooves 6, and the valve plate 2 is provided with a plurality of flow guide grooves 6.As shown, the valve plate 2 is arranged to rotate in the inner cavity of the valve housing 1, and the peripheral outer wall of the valve plate 2 and the inner side wall of the valve housing 1 have a gap 3 with an adjustable butterfly valve opening degree; the arrangement of the gap 3 in this embodiment ensures that the valve plate 2 has a rotating degree of freedom in the inner cavity of the valve housing 1 to realize accurate pressure regulation.

[0044] In an embodiment, as shown in Figure 2 As shown, the magnetic field generating part 4 is arranged on the inner side wall of the valve housing 1 and has a spacing with the valve plate 2, the magnetic field generating part 4 is connected with an alternating power supply and generates an alternating magnetic field when the alternating current is turned on, and the magnetic induction lines of the alternating magnetic field pass through the valve plate 2; the non-contact design in this embodiment not only ensures that the valve plate 2 can rotate freely in the inner cavity of the valve housing 1 to realize accurate pressure regulation, but also directly acts on the valve plate 2 made of metal material through the alternating magnetic field, so that eddy current is generated in the valve plate 2 based on electromagnetic induction effect and the valve plate 2 is self-heated; this “isolated heating” method not only avoids wear and interference caused by mechanical contact, but also realizes efficient and directional transmission of energy from magnetic field to heat, thereby providing the valve plate 2 with an efficient, uniform and controllable self-cleaning heat source, so as to effectively remove the process by-products attached to the surface, and fundamentally solve the problem of valve plate 2 blockage caused by sediment accumulation.

[0045] In an embodiment, the valve housing 1 is made of an insulating material, so that the eddy current circuit induced in the valve plate 2 by the alternating magnetic field generated by the magnetic field generating part 4 can be effectively blocked by the valve housing 1 to form a short circuit, thereby ensuring that most of the magnetic field energy is efficiently concentrated in the valve plate 2 to be converted into heat energy, and the efficiency of electromagnetic induction heating is significantly improved; at the same time, the insulating material avoids self-heating of the valve housing 1 due to induced current.

[0046] In an embodiment, the insulating material can be high-purity aluminum oxide ceramic, aluminum nitride ceramic or silicon nitride ceramic; the ceramic material not only has excellent electrical insulation performance, can effectively block the eddy current circuit induced in the valve plate 2 by the alternating magnetic field to form a short circuit through the valve housing 1, thereby ensuring that the magnetic field energy is efficiently concentrated in the valve plate 2 to be converted into heat energy, but also has good mechanical strength, high temperature resistance and plasma erosion resistance, which can meet the operation requirements of semiconductor process equipment for high cleanliness, high stability and long service life.

[0047] In an embodiment, the valve plate 2 is made of metal material which can effectively couple with the alternating magnetic field generated by the magnetic field generating member 4, so that the internal part of the valve plate 2 generates significant eddy current through electromagnetic induction effect to rapidly self-heat, thereby realizing efficient “from inside to outside” self-cleaning; compared with non-metallic material or external heating method, the thermal efficiency is higher, which can quickly remove the process by-products attached to the surface of the valve plate 2, fundamentally solves the problem of valve plate 2 blockage caused by sediment accumulation, and guarantees the pressure regulating accuracy and long-term operation reliability of the pressure control butterfly valve.

[0048] In an embodiment, the metal material can be stainless steel, hastelloy or titanium alloy which has good electrical conductivity and high temperature resistance; this metal material not only can effectively couple with the alternating magnetic field to generate significant eddy current heat effect, realizing rapid and uniform self-heating of the valve plate 2, but also has excellent corrosion resistance and mechanical strength, which can resist the corrosion of corrosive gases and thermal stress impact in the plasma process environment, thereby ensuring the long-term operation stability and service life of the pressure control butterfly valve under severe working conditions while ensuring the efficient self-cleaning function.

[0049] In an embodiment, the detection end of the by-product detection member faces the valve plate 2 for real-time acquisition of the by-product deposition information on the valve plate 2, so as to realize in-situ and real-time monitoring of the by-product deposition information on the surface of the valve plate 2. In some specific embodiments, the by-product detection member can directly acquire information reflecting the deposition thickness of the by-products and / or the coverage area of the by-products, providing accurate feedback basis for the control member, so as to change the traditional regular or passive cleaning to on-demand predictive maintenance based on actual working conditions, which not only ensures the timeliness and effectiveness of the cleaning action to prevent the valve plate 2 from being stuck due to excessive deposition, but also avoids energy waste caused by excessive cleaning, and significantly improves the intelligent level and operation reliability of the pressure control butterfly valve in the plasma process.

[0050] In an embodiment, the by-product detection member can be a laser scattering type particulate matter sensor, an optical interference film thickness measuring instrument or an infrared spectrum analyzer, so that the deposition thickness or coverage area of the by-products on the surface of the valve plate 2 can be monitored in real time based on optical principles in a non-contact manner, and the optical signals collected are converted into electrical signals corresponding to the by-product deposition thickness information and / or the by-product coverage area information and transmitted to the control member, so as to provide accurate data feedback for realizing on-demand predictive cleaning based on actual deposition state, effectively avoiding the blindness or hysteresis of traditional regular maintenance.

[0051] In an embodiment, the control element is connected with the by-product detection element and the magnetic field generating element 4, and controls the start and stop of the magnetic field generating element 4 according to the by-product deposition information collected by the by-product detection element. When the by-product deposition thickness information and / or the by-product coverage area information collected by the by-product detection element on the valve plate 2 is equal to or greater than a preset threshold value, the control element controls the magnetic field generating element 4 to generate an alternating magnetic field to make the valve plate 2 generate eddy current and self-heat according to the electromagnetic induction effect, so as to remove the by-products deposited on the valve plate 2. The closed-loop control system in this embodiment changes the equipment maintenance strategy from the traditional periodic or post-failure intervention to the predictive intelligent maintenance executed on demand. When the by-product detection element monitors in real time that the deposition amount on the surface of the valve plate 2 reaches a preset threshold value (in an embodiment, the value of the preset threshold value can be 0), the control element automatically starts the magnetic field generating element 4 (that is, controls the magnetic field generating element to be connected with the alternating power supply), so that the valve plate 2 generates induction heating. This can not only ensure that the self-cleaning function is triggered in time and accurately before the deposition accumulates to affect the action of the valve plate 2, thereby effectively preventing the blockage, but also avoid the energy waste caused by excessive cleaning or the performance decline caused by insufficient cleaning, thereby ensuring the pressure control accuracy while significantly improving the automation level and reliability of the equipment operation.

[0052] In an embodiment, the control element can be a programmable logic controller, a micro control unit or an industrial computer. The control element is configured to receive the by-product deposition thickness information and / or the by-product coverage area information from the by-product detection element, and accurately control the start and stop, output power and action time of the magnetic field generating element 4 based on a preset cleaning threshold value and algorithm logic, so as to realize the predictive intelligent cleaning on demand and adaptively, thereby effectively improving the automation level and operation reliability of the pressure control butterfly valve.

[0053] In an embodiment, as shown in Figure 2 The size of the gap 3 in the radial direction of the valve housing 1 is less than or equal to 0.2 mm, which ensures that there is enough space between the valve plate 2 and the valve housing 1 to avoid interference during rotation, thereby maximizing the reduction of the cross-sectional area of the gas leakage path, and effectively improving the sealing performance and pressure control accuracy of the valve. At the same time, the small gap 3 can significantly limit the deposition space of the process by-products in the gap 3 region, thereby reducing the risk of particle accumulation causing the valve plate 2 to be blocked, and creating favorable conditions for the subsequent electromagnetic induction-based self-cleaning function.

[0054] In an embodiment, the number of by-product detection pieces is provided with several, and the several by-product detection pieces are divided into a first group, a second group and a third group. The detection end of the by-product detection piece of the first group is directed to the top end surface of the valve plate 2, the detection end of the by-product detection piece of the second group is directed to the bottom end surface of the valve plate 2, and the detection end of the by-product detection piece of the third group is directed to the circumferential wall surface of the valve plate 2. In this embodiment, through the multi-point distributed layout, the residual state of the by-products on different surfaces of the valve plate 2 (including the easy deposition area) can be comprehensively and dead-angle-free monitored in real time, so as to provide more comprehensive and accurate deposition distribution data for the control piece, ensure that the self-cleaning operation can be intelligently triggered and the cleaning strategy can be optimized based on the actual deposition of the by-products on the whole valve plate 2, effectively avoid the problems of incomplete cleaning or excessive cleaning caused by local monitoring blind area, and significantly improve the pertinence of the cleaning process and the reliability of the system operation.

[0055] In an embodiment, the magnetic field generating piece 4 includes several straight wires 41.

[0056] In an embodiment, as shown in Figure 3 The straight wires 41 are arranged along the axial direction of the valve housing, that is, the axial direction of the several straight wires 41 is arranged in parallel with the axial direction of the valve housing 1, and the several straight wires 41 are evenly arranged on the inner side wall of the valve housing 1 along the circumferential direction, so as to generate an alternating magnetic field covering at least part of the valve plate 2 when energized, so that a uniformly distributed alternating magnetic field can be generated along the circumferential direction of the valve plate 2. When the wire is energized with an alternating current, the magnetic induction lines can effectively penetrate the valve plate 2, so that the inside of the valve plate 2 generates uniform eddy current and self-heating, thereby realizing rapid and uniform heating and self-cleaning of the surface of the valve plate 2. At the same time, the circumferential arrangement of the straight wires 41 is simple and easy to install compactly on the inner side wall of the valve housing 1, which is conducive to the magnetic field generating piece 4.

[0057] It is worth noting that, according to the Ampere rule, the alternating magnetic field generated in this embodiment penetrates into the valve plate 2 from one side wall of the valve plate 2 and penetrates out from another side wall of the valve plate 2.

[0058] In an embodiment, as shown in Figure 4As shown, the straight wires 41 are arranged radially along the valve housing, and a plurality of the straight wires 41 are arranged on the radial surface of one side near the gas inlet end of the valve housing 1 and / or the radial surface of one side near the gas outlet end of the valve housing 1; so that a local strong magnetic field can be generated upstream and / or downstream of the gas flow of the valve plate 2, and the corresponding edge area of the valve plate 2 is preferentially and concentratedly induced to generate heating, thereby efficiently removing the by-products more easily accumulated in the valve plate 2 due to the change of gas flow direction or the pressure difference between the top end surface and the bottom end surface of the valve plate 2; at the same time, compared with the circumferential full-coverage coil structure, this partitioned arrangement is more simplified, which can reduce the input cost and energy consumption of the magnetic field generating device 4 while ensuring efficient self-cleaning of the key area, and is especially suitable for working conditions with clear directionality characteristics of by-product deposition.

[0059] In one embodiment, as shown in Figure 2 The magnetic field generating device 4 includes a plurality of annular wires 42, which are arranged circumferentially along the valve housing 1, and a plurality of the annular wires 42 are arranged axially on the inner side wall of the valve housing 1 to generate magnetic induction lines penetrating into the valve plate 2 from the top end surface or the bottom end surface of the valve plate 2 when energized, wherein a plurality of the annular wires 42 are arranged coaxially and / or non-coaxially with the valve housing 1. This embodiment can flexibly configure the penetration path and intensity distribution of the magnetic field according to the cleaning needs of different areas of the valve plate 2. When the annular wires 42 are arranged coaxially with the valve housing 1, a magnetic field uniformly penetrating the top end surface or the bottom end surface of the valve plate 2 in the axial direction can be generated to achieve uniform heating of a large area; while when they are arranged non-coaxially, a local enhanced magnetic field can be generated in a specific area of the valve plate 2 to achieve targeted cleaning. This ensures efficient coverage of the valve plate 2 by the magnetic field, and adjusts the spatial arrangement and density of the annular wires 42, providing a flexible structural basis for optimizing heating uniformity and cleaning targeting.

[0060] In this embodiment, the magnetic field lines generated by the annular wires 42 penetrate into the valve plate 2 from the top end surface of the valve plate 2 and penetrate out from the bottom end surface of the valve plate 2; or the magnetic field lines penetrate into the valve plate 2 from the bottom end surface of the valve plate 2 and penetrate out from the top end surface of the valve plate 2.

[0061] In an embodiment, the magnetic field generating member 4 comprises a spiral coil arranged spirally along the axial direction of the valve housing 1 and around the inner side wall of the valve housing 1 to generate magnetic induction lines penetrating into the valve plate 2 from the top end surface or the bottom end surface of the valve plate 2 when energized. This embodiment can generate an alternating magnetic field distributed along the axial direction of the valve housing 1 and concentrated in a direction, so that the magnetic induction lines efficiently penetrate the top end surface or the bottom end surface of the valve plate 2 in a nearly vertical direction, thereby inducing a strong and uniformly distributed eddy current inside the valve plate 2 to achieve rapid and uniform self-heating of the valve plate 2. Compared with a local point or linear magnetic field, this spiral arrangement can achieve a larger area of covering heating on the surface of the valve plate 2, effectively avoid cleaning dead angles, and significantly improve the overall removal efficiency and uniformity of the attached by-products.

[0062] In an embodiment, the number of spiral coils is N, N is a positive integer greater than or equal to 2; N spiral coils are arranged in sequence along the axial direction of the valve housing 1 and the central axes of the N spiral coils coincide with the central axis of the valve housing 1, so that the magnetic induction lines generated by the N spiral coils penetrate the same position of the valve plate 2 when energized; so that the alternating magnetic fields generated by the N coils can achieve superposition and enhancement of magnetic field strength at the same axial position (such as the central region) of the valve plate 2, thereby generating significantly stronger induced eddy currents and thermal effects in this critical area; this design is particularly suitable for local intensive heating of specific high temperature demand areas of the valve plate 2, or for compensating for temperature unevenness caused by faster heat dissipation, achieving efficient and concentrated removal of stubborn deposits without excessive heating of the entire valve plate 2, and improving the targeting and energy efficiency ratio of self-cleaning.

[0063] In an embodiment, the N spiral coils are arranged in sequence along the radial direction of the valve housing 1 and away from the central axis of the valve housing 1, and the central axes of the spiral coils coincide with the central axis of the valve housing 1; so that the superposition and enhancement of the multi-layer magnetic field can be achieved in the same radial projection area of the valve plate 2, so that the energy of the alternating magnetic field penetrates the valve plate 2 more concentratedly, thereby inducing an eddy current with significantly improved strength inside the valve plate 2 to achieve efficient and concentrated heating of this area; this design is particularly suitable for local intensive cleaning of specific radial positions (such as the central region or the deposition prone area) of the valve plate 2, effectively improving the removal ability of stubborn by-products without excessive heating of the entire valve plate 2, while optimizing the spatial utilization of magnetic field energy.

[0064] In an embodiment, the N spiral coils are sequentially arranged along the radial direction of the valve housing 1 and away from the central axis of the valve housing 1, and the central axis of each spiral coil does not coincide with the central axis of the valve housing 1; so that the alternating magnetic field generated by each spiral coil is focused on a different radial position of the valve plate 2, thereby forming multiple independent local strong heating zones inside the valve plate 2; this design can be used to selectively or gradiently strengthen the heating of specific radial ring areas in view of the actual situation of uneven deposition of by-products on the surface of the valve plate 2, effectively improve the cleaning efficiency and the cleaning efficiency of non-uniform deposits, and avoid unnecessary energy input to areas with no or less deposition.

[0065] In an embodiment, the spiral coils gradually decrease in pitch along the axial direction of the valve housing 1 from the area close to the rotating shaft of the valve plate 2 to the edge area of the valve plate 2, so that the number of turns of the spiral coil located at the edge area of the valve plate 2 is more dense than the number of turns of the spiral coil located at the rotating shaft area of the valve plate 2, thereby generating a stronger alternating magnetic field at the edge area of the valve plate 2 than at the rotating shaft area of the valve plate 2. In this embodiment, the variable pitch structure makes the number of turns of the coil more dense at the edge area of the valve plate 2, thereby generating a significantly enhanced alternating magnetic field in this area; through the electromagnetic induction effect, the edge area of the valve plate 2 will induce stronger eddy currents and obtain higher heating power, effectively compensating for the problem of uneven axial temperature distribution of the valve plate 2 in actual work due to the fast heat dissipation of the central area close to the rotating shaft and the slow heat dissipation of the edge area, and finally achieving uniform heating of the valve plate 2 as a whole, avoiding incomplete cleaning or overheating damage in local areas, and significantly improving the uniformity and reliability of the self-cleaning effect.

[0066] In an embodiment, as Figure 5As shown, the magnetic field generating member includes at least one of a plurality of annular conductors 42 and a plurality of spiral coils, the annular conductors 42 and the spiral coils each include an inner layer coil 421 and an outer layer coil 422 along the radial direction of the valve housing 1, and the winding directions of the inner layer coil 421 and the outer layer coil 422 are opposite, so that the alternating magnetic fields generated by the inner layer coil 421 and the outer layer coil 422 are superimposed in the axial direction and constrained in the radial direction. The inner layer coil is arranged close to the central axis of the valve housing. This embodiment can utilize the magnetic field superposition principle generated by opposite currents to make the magnetic fields generated by the inner layer coil 421 and the outer layer coil 422 in the axial direction of the valve housing 1 mutually enhanced, thereby significantly improving the axial magnetic field intensity penetrating the valve plate 2; at the same time, in the radial direction, the alternating magnetic fields generated by the oppositely wound inner layer coil 421 and the outer layer coil 422 will form a mutual constraint effect, thereby more concentratedly restricting the magnetic field energy in the area where the valve plate 2 is located, effectively reducing the magnetic field leakage to the outside; this not only significantly improves the efficiency and energy utilization rate of electromagnetic induction heating, but also reduces the magnetic interference to the internal and peripheral elements of the valve housing 1, and realizes more precise and controllable directional heating and self-cleaning effect of the valve plate 2.

[0067] The alternating magnetic fields generated by the oppositely wound inner layer coil 421 and the outer layer coil 422 will form a mutual constraint effect, specifically, when the inner layer coil 421 and the outer layer coil 422 are supplied with currents in opposite directions, according to the right-hand screw rule, the magnetic fields generated by them in the radial component are in opposite directions, thereby forming a destructive superposition of magnetic field intensity in the radial space between the inner layer coil 421 and the outer layer coil 422; this mutual action of opposite magnetic fields makes the magnetic field energy more effectively constrained and concentrated in the area where the valve plate 2 is located close to the central axis of the valve housing 1, like forming a "magnetic confinement ring", significantly reducing the leakage and diffusion of the magnetic field to the outside of the valve housing 1. This not only improves the radial magnetic field gradient and energy density acting on the valve plate 2, enhances the efficiency and locality of electromagnetic induction heating, but also effectively reduces the magnetic interference to the peripheral components.

[0068] In one embodiment, the magnetic field generating component includes at least one of a plurality of straight wires 41, a plurality of loop wires 42, and a plurality of spiral coils, each of the straight wires 41, the loop wires 42, and the spiral coils being respectively and independently connected to the alternating power source to generate an alternating magnetic field for selective heating in different areas of the valve plate 2. This embodiment enables the control component to selectively energize and heat the magnetic field generating component 4 corresponding to areas with thicker deposition (e.g., the inlet end, the edge area, etc.) according to the actual distribution of the deposition on the surface of the valve plate 2, thereby achieving local and accurate reinforcement cleaning. This partitioned and independently driven strategy avoids the energy waste caused by traditional overall heating, significantly improves the cleaning targeting and efficiency, effectively reduces the overall energy consumption of the system, and prevents the risk of thermal damage caused by excessive heating of areas with no deposition or thinner deposition.

[0069] In one embodiment, as shown in Figure 2 The inner side wall of the valve housing 1 is recessed with a recess (not numbered), and the magnetic field generating component 4 is arranged in the recess. The magnetic field generating component 4 is embedded in the recess, or part of the magnetic field generating component 4 protrudes out of the recess, and the part of the magnetic field generating component 4 protruding out of the recess has a radial dimension less than or equal to 0.05 mm along the valve housing 1. This enables the magnetic field generating component 4 to be partially or completely embedded in the valve housing 1, so that the working surface of the magnetic field generating component 4 is flush with or only slightly protrudes (radial protrusion dimension ≤ 0.05 mm) from the inner side wall of the valve housing 1, thereby minimizing the interference with the gas flow field in the valve body lumen, avoiding the generation of vortex or local turbulence to aggravate particle deposition. At the same time, the recess provides stable installation positioning and mechanical protection for the magnetic field generating component 4, ensures effective penetration of the alternating magnetic field to the valve plate 2, maintains the smoothness and air tightness of the valve flow passage, and is conducive to maintaining the pressure control accuracy and prolonging the service life of the element.

[0070] In one embodiment, as shown in Figure 3As shown, the inner side wall of the valve housing 1 is provided with a plurality of flow guide grooves 6 extending in the axial direction at equal intervals in the circumferential direction, i.e., the length direction of the groove cavity of each flow guide groove 6 is the axial direction of the valve housing 1, to guide the gas to flow from the gas inlet end to the gas outlet end of the valve housing 1, thereby reducing the vortex effect of the gas. This embodiment effectively guides the gas flowing through the valve cavity to flow smoothly along the axial direction of the valve housing 1 from the gas inlet end to the gas outlet end, significantly reducing the vortex and turbulent flow phenomena caused by sudden changes in the flow path or the valve plate 2 obstruction. This not only helps to reduce the gas flow resistance and maintain stable pressure control, but also effectively suppresses the disordered deposition of particulate matter in the process gas in the gap 3 area and on the surface of the valve plate 2, thereby slowing down the accumulation speed of by-products from the source, improving the valve sealing performance, extending the self-cleaning cycle, and ensuring the long-term operation stability of the pressure control butterfly valve.

[0071] In one embodiment, a plurality of temperature sensors are arranged in the valve housing 1, with the detection ends of the temperature sensors respectively facing the top end surface, the bottom end surface, and the circumferential side wall of the valve plate 2 to monitor the temperature on the top end surface, the bottom end surface, and the circumferential side wall of the valve plate 2 in real time. The temperature sensors are in communication or electrically connected with the control member. This multi-point distributed temperature monitoring layout can obtain the actual temperature distribution data of the valve plate 2 at different surface positions in real time and accurately, providing closed-loop feedback for the control member. The control member can dynamically adjust the output power or action time of the magnetic field generating member 4 accordingly, thereby achieving precise temperature control of the self-heating process of the valve plate 2, ensuring the effective temperature required for self-cleaning to avoid insufficient cleaning, and preventing the valve plate 2 from being damaged due to local overheating, significantly improving the safety and reliability of system operation.

[0072] In one embodiment, as shown in Figure 6 The hollow cavity is filled with a phase change energy storage material, which absorbs or releases a large amount of latent heat when it undergoes a phase change (such as solid to liquid phase change), thereby storing excess heat energy during the energization stage of the magnetic field generating member 4 and slowly releasing it after de-energization to maintain the temperature of the valve plate 2, effectively extending the self-cleaning action time and improving the removal effect of stubborn by-products. At the same time, this heat storage characteristic helps to smooth the temperature fluctuations of the valve plate 2 during intermittent heating, reducing thermal stress impact, ensuring cleaning efficiency, and further improving the stability and service life of the valve plate 2 in operation.

[0073] In one embodiment, the phase change energy storage material can be a high latent heat material with a suitable phase change temperature, such as paraffin, hydrated salt, or metal alloy. Such materials can absorb and store a large amount of latent heat during the self-heating stage of the valve plate 2, and effectively maintain the operating temperature of the valve plate 2 by slowly releasing the stored heat after power failure. This extends the self-cleaning time, improves the removal effect on stubborn by-products, and helps to smooth the temperature fluctuation of the valve plate 2 during intermittent heating, thereby enhancing the thermal stability of the system.

[0074] In one embodiment, such as Figure 1 and Figure 2 As shown, the pressure-controlled butterfly valve with self-cleaning function also includes a valve controller 7 and a connector 8. The valve controller 7 is located outside the valve housing 1, and the connector 8 is located on the valve housing 1 and is used to connect the valve controller 7 and the valve plate 2, so as to transmit the driving force of the valve controller 7 to make the valve plate 2 rotate inside the valve housing 1, thereby adjusting the opening degree of the butterfly valve.

[0075] In one embodiment, the valve controller 7 can be a servo motor, a stepper motor, or a piezoelectric ceramic actuator. The valve controller 7 can receive pressure control signals from the host system and transmit precise angular or linear displacement to the valve plate 2 through the connector 8, thereby achieving precise and rapid adjustment of the butterfly valve opening to maintain the high-precision vacuum pressure environment required in the plasma process chamber 12. At the same time, its own closed-loop control function can work in conjunction with the control components to ensure the stable and controllable position of the valve plate 2 during the self-cleaning process.

[0076] In one embodiment, the connector 8 can be a metal bellows, a ceramic connecting rod, or a magnetic coupling transmission mechanism; such connector 8 can reliably transmit the driving force of the valve controller 7 to the valve plate 2 to adjust the opening of the butterfly valve, while ensuring the high vacuum sealing inside the valve body 1, and has good high temperature resistance and corrosion resistance to adapt to the harsh working conditions in the plasma process environment and ensure the long-term stable operation of the pressure-controlled butterfly valve.

[0077] In one embodiment, the plasma processing device, such as Figure 1As shown, the system comprises a process chamber 12, an exhaust pump 9, an exhaust on-off valve 10, a plasma generating device 11, and the pressure control butterfly valve with self-cleaning function. The process chamber 12 and the exhaust pump 9 are connected by a pipeline, the pressure control butterfly valve with self-cleaning function is arranged on the pipeline, the exhaust on-off valve 10 is arranged between the pressure control butterfly valve with self-cleaning function and the exhaust pump 9, and the plasma generating device 11 is arranged in the process chamber 12. The arrangement of the embodiment enables the pressure control butterfly valve to precisely regulate the exhaust flow pressure of the process chamber 12, and the self-cleaning function of the pressure control butterfly valve can clean the by-products deposited on the valve plate 2 due to the condensation of process gas, thereby preventing the valve plate 2 from being blocked, ensuring the long-term stability and control accuracy of the vacuum pressure in the plasma process, and significantly improving the operation reliability and production efficiency of the entire plasma processing equipment.

[0078] In an embodiment, the plasma processing equipment can be a plasma etching equipment, a plasma chemical vapor deposition equipment, or a plasma stripping equipment. By integrating the pressure control butterfly valve with self-cleaning function on the vacuum pipeline between the process chamber 12 and the exhaust pump 9 of the equipment, the equipment can achieve high-precision and high-stability control of the vacuum pressure of the process chamber 12 during the key processes such as wafer etching, film deposition, or photoresist removal, and effectively prevent the valve plate 2 from being blocked due to the deposition of by-products by using the self-cleaning function of the pressure control butterfly valve, thereby ensuring the uniformity and repeatability of the plasma process and improving the overall production capacity and product yield of the equipment.

[0079] Although the embodiments of the present application have been described in detail above, it is obvious to those skilled in the art that various modifications and changes can be made to the embodiments. However, it should be understood that such modifications and changes are within the scope and spirit of the present application. Moreover, the present application described herein can have other embodiments and can be implemented or realized in various ways.

Claims

1. A pressure-controlled butterfly valve with self-cleaning function, characterized in that, This includes valve body, valve plate, magnetic field generating components, by-product detection components, and control components; The valve plate is rotatably disposed within the inner cavity of the valve housing and is made of metal. The valve housing is made of insulating material. An adjustable butterfly valve opening clearance exists between the outer circumferential wall of the valve plate and the inner sidewall of the valve housing. The magnetic field generating element is disposed on the inner wall of the valve housing and has a gap with the valve plate. The magnetic field generating element is connected to an alternating power supply and generates an alternating magnetic field in which magnetic field lines pass through the valve plate when an alternating current is applied. The detection end of the by-product detection device faces the valve plate to collect by-product deposition information on the valve plate in real time. The control unit is connected to the by-product detection unit and the magnetic field generating unit. The control unit controls the magnetic field generating unit to generate an alternating magnetic field according to the by-product deposition information, so that the valve plate generates eddy currents and self-heats according to the electromagnetic induction effect, thereby removing the by-products deposited on the valve plate. The valve plate has a hollow cavity inside, which is filled with a phase change energy storage material to maintain the temperature of the valve plate after power failure by utilizing the heat storage characteristics of the phase change energy storage material itself.

2. The pressure-controlled butterfly valve with self-cleaning function according to claim 1, characterized in that, The gap is less than or equal to 0.2 mm in the radial direction of the valve body.

3. The pressure-controlled butterfly valve with self-cleaning function according to claim 1, characterized in that, The number of by-product detection devices is set to several, and the several by-product detection devices are divided into a first group, a second group and a third group. The detection end of the by-product detection device in the first group faces the top surface of the valve plate, the detection end of the by-product detection device in the second group faces the bottom surface of the valve plate, and the detection end of the by-product detection device in the third group faces the circumferential wall surface of the valve plate.

4. The pressure-controlled butterfly valve with self-cleaning function according to claim 1, characterized in that, The magnetic field generating device includes several straight conductors; The straight conductor is arranged along the axial direction of the valve body, and several straight conductors are equally spaced along the circumference on the inner sidewall of the valve body to generate an alternating magnetic field covering at least part of the valve plate when energized. And / or the straight conductor is arranged radially along the valve body, and a plurality of the straight conductors are arranged on a radial surface near the air inlet end of the valve body and / or on a radial surface near the air outlet end of the valve body.

5. The pressure-controlled butterfly valve with self-cleaning function according to claim 1, characterized in that, The magnetic field generating device includes a plurality of annular wires arranged circumferentially along the valve housing, and the plurality of annular wires arranged axially on the inner sidewall of the valve housing to generate magnetic field lines that penetrate the valve plate from the top or bottom surface of the valve plate when energized. The plurality of annular wires are arranged coaxially and / or non-coaxially with the valve housing.

6. The pressure-controlled butterfly valve with self-cleaning function according to claim 1, characterized in that, The magnetic field generating component includes a spiral coil, which is arranged in a spiral pattern around the inner wall of the valve housing and along the axial direction of the valve housing, so as to generate magnetic field lines that penetrate the valve plate from the top or bottom surface of the valve plate when energized.

7. The pressure-controlled butterfly valve with self-cleaning function according to claim 6, characterized in that, The number of spiral coils is set to N, where N is a positive integer greater than or equal to 2; N spiral coils are arranged sequentially at intervals along the axial direction of the valve body, and the central axis of each of the N spiral coils coincides with the central axis of the valve body, so that when energized, the magnetic field lines generated by the N spiral coils pass through the same position of the valve plate. And / or N spiral coils are sequentially sleeved along the radial direction of the valve housing and toward a direction away from the central axis of the valve housing, and the central axis of each spiral coil may or may not coincide with the central axis of the valve housing.

8. The pressure-controlled butterfly valve with self-cleaning function according to claim 7, characterized in that, The pitch of the spiral coil gradually decreases along the axial direction of the valve housing from the rotation axis region near the valve plate to the edge region of the valve plate, so that the number of turns of the spiral coil located in the edge region of the valve plate is more dense than the number of turns of the spiral coil located in the rotation axis region of the valve plate, thereby generating a stronger alternating magnetic field in the edge region of the valve plate than in the rotation axis region of the valve plate.

9. The pressure-controlled butterfly valve with self-cleaning function according to claim 1, characterized in that, The magnetic field generating device includes at least one of several annular wires and several helical coils. Both the annular wires and the helical coils include an inner coil and an outer coil along the radial direction of the valve housing, and the inner coils and the outer coils are wound in opposite directions so that the alternating magnetic fields generated when the inner coils and the outer coils are energized are superimposed on each other in the axial direction and constrained on each other in the radial direction. The inner coils are arranged close to the central axis of the valve housing.

10. The pressure-controlled butterfly valve with self-cleaning function according to claim 1, characterized in that, The magnetic field generating device includes at least one of several straight wires, several loop wires, and several spiral coils. Each of the straight wires, each of the loop wires, and each of the spiral coils is independently connected to the alternating power supply to generate an alternating magnetic field that selectively heats different regions of the valve plate.

11. The pressure-controlled butterfly valve with self-cleaning function according to claim 2, characterized in that, The inner wall of the valve housing has a recessed portion, and the magnetic field generating component is disposed in the recessed portion; The magnetic field generating component is embedded in the recessed portion; Alternatively, a portion of the magnetic field generating element may protrude beyond the recess, and the radial dimension of the portion of the magnetic field generating element protruding from the recess along the valve housing may be less than or equal to 0.05 mm.

12. The pressure-controlled butterfly valve with self-cleaning function according to claim 1, characterized in that, The inner wall of the valve housing is provided with a number of axially extending guide grooves at equal intervals along its circumference to guide the gas from the inlet end to the outlet end of the valve housing, thereby reducing the vortex effect generated by the gas.

13. The pressure-controlled butterfly valve with self-cleaning function according to claim 1, characterized in that, The valve housing is equipped with several temperature sensors, which are respectively oriented towards the top surface, bottom surface, and circumferential sidewall of the valve plate to monitor the temperature on the top surface, bottom surface, and circumferential sidewall of the valve plate in real time. The temperature sensors are connected to the control component.

14. The pressure-controlled butterfly valve with self-cleaning function according to claim 1, characterized in that, It also includes a valve controller and a connector. The valve controller is located outside the valve housing, and the connector is located on the valve housing and is used to connect the valve controller and the valve plate to transmit the driving force of the valve controller to make the valve plate rotate inside the valve housing, thereby adjusting the opening degree of the butterfly valve.

15. A plasma processing device, characterized in that, The device includes a process chamber, a vacuum pump, a vacuum switch valve, a plasma generator, and a pressure-controlled butterfly valve with a self-cleaning function as described in any one of claims 1 to 14. The process chamber and the vacuum pump are connected by a pipeline. The pressure-controlled butterfly valve with the self-cleaning function is disposed on the pipeline. The vacuum switch valve is disposed between the pressure-controlled butterfly valve with the self-cleaning function and the vacuum pump. The plasma generator is disposed in the process chamber.

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