Vacuum valves for symmetrical fluid flow

Abstract

The invention relates to a vacuum valve for providing a symmetrical fluid flow. The vacuum valve is used for adjusting a volume flow or a mass flow and for airtightly interrupting a flow path, and comprises: a first valve seat having a first valve opening (11a) defining a first opening axis and a first sealing surface (12a) surrounding the first valve opening (11a); and a first valve disc (13a) having a first contact surface (14a) corresponding to the first sealing surface (12a). The valve also comprises a drive unit, which is designed and connected to the first valve disc (13a) in such a way that it can at least be moved from an open position to a closed position and can be moved back. The vacuum regulating valve (10) comprises at least one second valve seat having a second valve opening (11b) defining a second opening axis and a second sealing surface (12b) surrounding the second valve opening (11b). In addition, the second valve disc (13b) is provided with a second contact surface (14b) corresponding to the second sealing surface (12b). The total valve opening of the vacuum regulating valve is composed of a first valve opening (11a) as a first valve opening and a second valve opening (11b) as a second valve opening.

Description

Technical Field

[0001] The invention relates to a vacuum regulating valve having a plurality of valve discs and a corresponding plurality of valve sub-openings. Background Art

[0002] In general, different embodiments of vacuum valves for regulating volume flows or mass flows and for substantially gas-tight closing of a flow path extending through an opening formed in a valve body are known from the prior art and are used in particular in vacuum chamber systems in the field of integrated circuit processing, semiconductor processing or substrate processing, which must take place in a protective atmosphere with as little contamination particles as possible.

[0003] Such a vacuum system comprises in particular at least one evacuable vacuum chamber for accommodating semiconductor elements or substrates to be processed or manufactured and at least one vacuum pump for evacuating the vacuum chamber, and the semiconductor elements or other substrates can enter and exit the vacuum chamber through at least one vacuum chamber opening provided in the vacuum chamber. For example, in a processing device for semiconductor wafers or liquid crystal substrates, highly sensitive semiconductor elements or liquid crystal elements sequentially pass through a plurality of processing vacuum chambers, and the components located in the processing vacuum chambers are processed in the processing vacuum chambers respectively by processing devices. Not only during the processing process in the processing vacuum chambers, but also during the transportation between chambers, the highly sensitive semiconductor elements or substrates must always be in a protective atmosphere, in particular in an air-evacuated environment.

[0004] For this purpose, peripheral valves are used on the one hand to open and close the gas input and discharge, and transfer valves are used on the other hand to open and close the transfer openings of the vacuum chamber for feeding in and out the components.

[0005] The vacuum valves through which semiconductor components pass are called vacuum transfer valves due to the aforementioned fields of application and the associated dimensions, rectangular valves due to their mostly rectangular opening cross section, and slide valves, rectangular valves or transfer slide valves due to their common mode of operation.

[0006] Peripheral valves are used in particular to control or regulate the gas flow between a vacuum chamber and a vacuum pump or another vacuum chamber. The peripheral valve is located, for example, in a pipe system between a process vacuum chamber or a transfer chamber and a vacuum pump, the surroundings or another process vacuum chamber. The opening cross section of such a valve (also called a peripheral valve) is generally smaller than the opening cross section in a vacuum transfer valve. Since peripheral valves are used not only to fully open and fully close an opening, but also to control or regulate the flow rate between a fully open position and a gas-tight closed position by continuously moving the opening cross section, depending on the field of application, they are also called regulating valves. A possible peripheral valve for controlling or regulating the gas flow is a swing valve.

[0007] In the case of a typical swing valve, such as disclosed by US Pat. No. 6,089,537 (Olmsted), in a first step, a generally circular valve disc is pivoted through a generally circular opening from a position opening the opening to an intermediate position covering the opening. In a slide valve such as described in US Pat. No. 6,416,037 (Geiser) or US Pat. No. 6,056,266 (Blecha), the valve disc and the opening are mostly designed as a rectangle and in a first step are linearly moved from a position opening the opening to an intermediate position covering the opening. In this intermediate position, the valve disc of the swing valve or slide valve is spaced opposite to the valve seat surrounding the opening. In a second step, the distance between the valve disc and the valve seat is reduced, so that the valve disc and the valve seat are evenly pressed against each other and the opening is basically airtightly closed. The second movement is preferably carried out essentially in a direction perpendicular to the valve seat. The sealing can be carried out, for example, by a sealing ring arranged on the closing side of the valve disc and pressed onto the valve seat surrounding the opening, or by a sealing ring on the valve seat, onto which the closing side of the valve disc is pressed. By the closing process performed in the second step, the sealing ring between the valve disc and the valve seat is hardly subjected to shear forces that would damage the sealing ring, because the movement of the valve disc in the second step occurs substantially straight and perpendicular to the valve seat.

[0008] Different sealing devices are known from the prior art, for example from US Pat. No. 6,629,682 B2 (Duelli). Suitable materials for sealing rings and seals in vacuum valves are, for example, fluorinated rubber, also called FKM, in particular the fluorinated elastomer known by the trade name "Viton", and perfluoro rubber, abbreviated as FFKM.

[0009] In addition to the advantage that the seal is almost only pressed vertically without lateral and longitudinal loads on the seal (avoiding particles), the multi-stage movement in which the closing element is first moved laterally through the opening without any contact between the seal and the valve seat and the valve closing element is pressed essentially vertically against the valve seat in the interface also offers the possibility of adjusting the flow of a medium (such as a process gas) through the valve opening.

[0010] Since the valves described above are used in particular in the production of highly sensitive semiconductor components, the particle generation caused in particular by the valve actuation and mechanical loading of the valve closure and the number of free particles in the valve space must be kept as low as possible, as already described. Particle generation is primarily a result of friction, for example caused by metal-to-metal contact or wear.

[0011] As mentioned above, vacuum control valves are used to adjust a defined process environment in a process chamber. The adjustment is generally carried out based on a pressure signal that provides information about the pressure in the chamber and based on a target parameter, namely a setpoint pressure, which is to be achieved with the aid of the controller. The adjustment of the valve closing element (valve disk) is then changed within the scope of the controller so that the setpoint pressure is achieved within a defined period.

[0012] The above embodiments have in common that, in particular during regulation, a regulation curve (volume flow in relation to a time unit) occurs due to one of the described structures, which generally has an unfavorable curve profile. In particular, the brief transition from the nearly closed valve state to the fully closed valve state shows a significantly uneven curve profile, since a "snap-off effect" occurs here. The flow through the opening is suddenly interrupted here. Fine regulation at low pressures can therefore only be achieved with difficulty or is impossible.

[0013] As a further key factor in connection with semiconductor processing, the use and delivery of process gases required for some of the processing steps is mentioned. In this case, the regulating valve generally also has the function of providing, i.e. regulating a defined gas concentration by means of variable gas discharge through the valve. The process gas is then mostly supplied to the side of the process chamber opposite the evacuation opening. In addition to the gas concentration and the atmospheric pressure, in this case, it is also advantageous to distribute the process gas as evenly as possible at least in the area of ​​the substrate to be processed. Therefore, it may help to have a symmetrical flow of the gas through the process chamber both during the gas supply and during the evacuation.

[0014] US6,994,311B2 discloses a vacuum regulating valve, the purpose of which is to generate a symmetrical flow through the opening in the open valve position. The valve disc is centrally suspended on a guide (valve stem) and can be guided axially, so that the volume flow through the opening can be adjusted depending on the distance between the valve disc and the valve seat.

[0015] However, a disadvantage of this solution is that a mechanical connection into the center of the valve opening must be present in order to provide guidance of the valve disk. The mechanical connection at least partially resolves the flow symmetry and leads to vortices at the connection. Summary of the invention

[0016] The invention is therefore based on the object of providing a vacuum control valve which, on the one hand, provides a precise adjustment or regulation of the valve opening and thus of the flow through the opening and, on the other hand, provides a uniform flow through the valve opening.

[0017] The object of the present invention is to provide the above-mentioned improvement in particular with respect to the relatively short adjustment times of the valve closure element.

[0018] The present invention relates to a vacuum valve, in particular a vacuum regulating valve, which provides improved uniformity of flow characteristics for the flow of process fluids into and out of a process volume. At the same time, the regulation time for the change from an open state to a closed state (or vice versa) can be significantly improved, i.e. shortened.

[0019] The advantages and improvements are provided by dividing the previously only valve opening known in the prior art into a plurality of valve sub-openings in a vacuum valve. The sub-openings are arranged symmetrically about the central valve axis. Each valve sub-opening is provided by a valve seat and is surrounded by a sealing surface. The sum of the areas of the plurality of valve sub-openings represents the total valve opening area.

[0020] The total valve opening cross section results from the sum of the opening cross sections of a plurality of valve sub-openings, wherein the opening cross section depends on the respective opening state of the valve sub-openings, ie the flow surface which is opened by the respective valve closing element.

[0021] By dividing the valve openings and the consequent arrangement of a plurality of valve closing elements (valve disks), a structure can be provided in which, in an open position, i.e. when providing a maximum flow rate (volume flow), the valve closing elements no longer or at least no longer substantially cover the respective valve opening. In other words, the valve disks can be adjusted and moved in such a way that the valve openings are substantially, in particular completely, opened. The valve closing elements can be in the fully open position or substantially completely removed from the flow channel (flow channel) connecting the first connection and the second connection of the vacuum control valve.

[0022] By removing the valve closure from the flow channel, the need to arrange mechanical parts in the flow channel that are required to connect the valve closure can be avoided. In the flow channel, no moving parts or mechanical parts are in the open position. There is only a structurally fixed arrangement to define the valve seat. However, this fixed structure can advantageously be designed so that it also has a symmetrical shape and size centered on the central axis. By such a design, a highly symmetrical flow through the valve can be provided in each open state.

[0023] The vacuum valve according to the invention has a drive unit which comprises at least one drive component, in particular a number of drive components which corresponds to the number of valve closing elements. The drive component can be designed as an electric motor, for example.

[0024] Therefore, the present invention relates to a vacuum regulating valve for regulating a volume flow or a mass flow and interrupting a flow path in a gas-tight manner. The vacuum regulating valve has a first valve seat, which in turn has a first valve opening defining a first opening axis and a first sealing surface surrounding the first valve opening. In addition, a first valve disc having a first contact surface corresponding to the first sealing surface is provided.

[0025] The vacuum regulating valve also has a drive unit, which is designed and connected to the first valve disc so that the valve disc can at least move from an open position to a closed position and reverse movement (such as motorized return). In the open position, the first valve disc and the first valve seat are not in contact with each other relative to each other. In the closed position, an axial sealing contact exists between the first sealing surface and the first contact surface through a seal therebetween, and the first valve opening is thereby hermetically closed.

[0026] According to the invention, the vacuum control valve has at least one second valve seat with a second valve opening defining a second opening axis and a second sealing surface surrounding the second valve opening. In addition, the valve has a second valve disk with a second contact surface corresponding to the second sealing surface. The total valve opening of the vacuum control valve is thus formed by the first valve opening as the first valve sub-opening and the second valve opening as the second valve sub-opening.

[0027] The provision of at least two groups, each comprising at least one valve seat and one valve closure element, allows a symmetrical arrangement centered on the center of the vacuum valve, wherein covering of the valve opening by the valve closure element in the open position can be at least substantially avoided. For this purpose, on the one hand, a symmetrical volume flow through the valve can be provided, and on the other hand, a relatively fast actuation (i.e., a fast movement of the valve closure element due to the low individual mass of the valve closure element) can be provided, whereby a very flexible volume flow adjustment can be achieved, i.e., a larger total opening cross section can also be obtained within a short time from the closed position (or vice versa).

[0028] In one embodiment, the vacuum regulating valve comprises a third valve opening defining a third opening axis and a third valve seat surrounding the third valve opening and a third sealing surface and a third valve disk having a third contact surface corresponding to the third sealing surface. The valve total opening is then also formed by the third valve opening as the third valve sub-opening.

[0029] By arranging the third combination or other combinations of valve seat and valve disk, symmetry of the valve opening about the valve center axis can be achieved, thereby further improving the symmetry of the volume flow (concentrically) flowing through the valve.

[0030] The drive unit is particularly connected to the second valve disc, particularly the third valve disc, in such a way that the connected valve discs can be moved at least from respective open positions to closed positions and back, wherein in the open position the respective valve discs and the respective valve seats are relatively non-contacting with each other, and in the closed position there is axial sealing contact between the respective sealing surfaces and the respective contact surfaces via the seals respectively located therebetween, whereby the respective valve sub-openings are hermetically closed.

[0031] In one embodiment, the vacuum regulating valve can have a connecting mechanism, which provides a mechanical connection between the first valve disc and the second valve disc, in particular the third valve disc, and is connected to the drive unit in such a way that the respective valve discs can be moved together by means of the drive unit. The connecting mechanism can be realized, for example, with a shaft, a hinge (such as a universal joint), a bearing and / or a transmission mechanism.

[0032] Thus, for example, a simultaneous adjustment movement of all connected valve disks can be provided by means of a mechanical solution. In particular, a uniform and symmetrical flow of the fluid through the valve can be achieved in that, already during the initial opening of the valve sub-openings, the same opening cross section is provided for all openings and the flow through all openings is and remains the same in terms of volume flow or mass flow.

[0033] According to another embodiment, the drive unit has at least a first and a second drive component, in particular a third drive component, in particular respective motors. The first drive component is connected to the first valve disk, the second drive component is connected to the second valve disk, in particular the third drive component is connected to the third valve disk.

[0034] In contrast to the previous embodiments, in this variant each of the valve disks can be controlled and moved individually. This allows a greater flexibility in adjusting the flow properties through the valve. For example, volume flow asymmetries caused by processing devices present in the process chamber can thereby be compensated. This compensation can be achieved by providing different opening cross sections for several valve sub-openings.

[0035] In particular, the flow properties in the chamber can be adjusted in such a way that asymmetric flows, for example due to substrate processing devices (such as chucks, supports, electrodes, etc.) in the chamber can be compensated. The flow will flow through the processing chamber correspondingly unevenly when using a common valve. By means of the adjustability of the outflow characteristics of the valve of the present invention, the outflow of the fluid can resist the asymmetric flow through the chamber, thus ultimately resulting in an overall symmetrical flow through the chamber. The flow through the valve can now be correspondingly asymmetric (not centered, i.e. asymmetric about the central axis). For example, different flow rates may exist on different (such as opposite) valve sides.

[0036] The vacuum control valve can in particular have a control unit, in particular a control unit, wherein the drive unit (and its drive components) can be controlled in accordance with a control signal provided by the control unit, in particular in accordance with a controlled parameter. Each drive component of the drive unit can in particular be controlled independently by means of (individual) control signals.

[0037] In one embodiment, the vacuum regulating valve may have a first interface and a second interface, wherein the first and second valve seats are arranged in a flow channel, which connects the first interface and the second interface and defines a flow path, especially wherein the first and second valve discs are at least substantially, and in particular completely, located outside the flow channel in the open position.

[0038] The two interfaces can be provided in particular for arranging a vacuum control valve between a process chamber or vacuum chamber and a vacuum pump. Thus, due to the purposeful setting or adjustment of the valve opening state, the setpoint pressure or pressure distribution in the chamber can be set or adjusted by generating a negative pressure on the vacuum pump side. In other words, the two interfaces thus define a flow channel, which can be completely or partially closed by the valve closure.

[0039] In one embodiment, the first and second valve sub-openings, in particular the third valve sub-opening, can be arranged symmetrically around a central axis of the vacuum regulating valve, wherein the central axis extends through the valve center, in particular forming a central axis of the flow channel. The valve can define a flow path for the fluid on the one hand and a limited flow channel for the fluid on the other hand due to its geometric shape. The central axis is in particular located in the center of the flow channel and extends according to the extension of the flow channel.

[0040] At least one of the valve discs can be linearly adjusted and moved along the adjustment axis. The valve closing member can also be designed to be linearly adjustable and moved. The contact surface (sealing surface) of the closing member can have a substantially identical distance from the corresponding sealing surface of the valve seat at every moment during the movement. The first sealing plane defined by the sealing surface can now (always) be oriented parallel to the second sealing plane (contact plane) defined by the contact surface. The valve closing member will move parallel to the valve seat. Alternatively, the valve closing member can be designed to be rotatably mounted.

[0041] In one embodiment, at least one of the valve discs can be designed as a flap valve closing element which is rotatably mounted about a rotation axis.

[0042] The drive unit and at least one of the valve disks can be designed and can cooperate, in particular connected, in such a way that the at least one valve disk can be moved into a fine adjustment position in which the at least one valve disk is positioned at a defined tilt relative to the associated valve seat so that the first sealing plane and the second sealing plane enclose a defined angle, wherein the associated sealing surface defines the first sealing plane and the associated contact surface defines the second sealing plane. The seal can here completely rest against the associated sealing surface or contact surface and only partially against the respective other sealing surface or contact surface.

[0043] In the fine adjustment position, the area portion of the seal in which the opposing sealing surfaces are in contact or pressed is therefore smaller than in the closed position.

[0044] By means of this purposeful relative inclination between the valve seat and the valve closure and the opening range of the valve opening which can be set according to the inclination, advantageous pressure and flow control is achieved. Such a control can be used, for example, in general when using process gases and the theoretical pressure setting requirements associated therewith. By means of the continuous laminar flow of the medium through the opening which can be caused thereby, pressure fluctuations can be avoided and the theoretical pressure can be achieved more quickly. By means of the possibility of complete separation of the valve disc from the valve seat (open position), the flow opening can on the other hand be selected to be very large.

[0045] A larger opening angle means a larger flow opening and thus a larger flow rate per unit time. By reducing the opening angle, the flow rate can be reduced stepwise and / or continuously until there is complete contact of the sealing surfaces or seals of the valve seat and valve disk and thus the sub-opening is therefore in the fully closed state (closed position).

[0046] By means of the valve according to the invention, the above-mentioned flows can advantageously also be regulated, ie at very low pressures, while providing and maintaining a substantially symmetrical laminar flow.

[0047] In one embodiment, the drive unit and at least one of the valve discs can be designed and connected in such a way that, when at least one of the valve discs moves from the open position to the closed position or vice versa, the at least one valve disc is in the fine-tuning position before reaching the closed position or the open position. This can be achieved, for example, by correspondingly controlling or adjusting the drive unit, for example by a controllable tilting of the disc relative to the valve seat.

[0048] With regard to the orientation of the valve seat sealing surface, according to one embodiment, the first sealing surface (of the valve seat) may point in a direction parallel to the opening axis and extend orthogonally to the opening axis.

[0049] According to one embodiment of the invention, at least one of the valve disks is positioned in the fine adjustment position in such a way that the second sealing surface defined by the extension of its contact surface is inclined relative to the opening axis.

[0050] In one embodiment, the first sealing plane and the second sealing plane enclose a specified angle α in the open position and the fine-tuning position, and the first and second sealing planes are substantially parallel to each other in the closed position. Therefore, when moving from the fine-tuning position to the closed position, the value of the angle α always approaches zero and eventually becomes zero.

[0051] Obviously, according to one embodiment, not only a single fine-tuning position can be adjusted, but also a second fine-tuning position, several fine-tuning positions or multiple fine-tuning positions can be adjusted in particular continuously. n The first and second sealing surfaces are respectively different and are only partially in contact with each other by means of the seal (seal). The multiple fine adjustment positions can therefore respectively correspond to another tilting posture of the valve disk relative to the valve seat. In particular, each tilting position can be assigned to a respective fine adjustment position during the continuous closing movement.

[0052] In particular, the prescribed flow characteristic can be set and / or adjusted jointly by the vacuum control valve, in particular by the at least two valve openings, in particular the flow characteristic being adjusted asymmetrically with respect to a central axis of the vacuum control valve. The central axis here extends through the valve center, in particular it forms the central axis of the flow channel. In this way, at least partial compensation of the flow characteristic which initially occurs asymmetrically due to the asymmetry in the chamber can be achieved.

[0053] The fine adjustment position can be adjusted individually or continuously in a controllable manner, thereby providing a continuous adjustment of the volume flow or mass flow through the valve opening. In this case, the flow can be maintained in particular as a laminar flow. Such adjustment is provided in particular by a stepper motor or a servo motor or a drive unit, whereby a rotation of the valve disk is provided.

[0054] According to one embodiment, the first valve seat and the second valve seat can be arranged in the same plane. Alternatively, the first valve seat and the second valve seat are arranged so as to be inclined relative to each other that a plane defined by the first sealing surface and a plane defined by the second sealing surface enclose a predetermined angle. The valve seat can be oriented, for example, so that the defined sealing planes each include a side surface of a virtual pyramid.

[0055] In one embodiment, the orientation may be such that an opening axis defined by the respective valve opening of the valve seat intersects the center of the respective valve opening and extends orthogonally to the respective sealing plane defined by the extension of the respective sealing surface and intersects the respective opening axis, in particular at the same intersection point. The same intersection point is in particular located on the center axis of the valve.

[0056] According to one embodiment, the drive unit has at least one motor and at least one guide element, in particular a guide rod, which is movable along the longitudinal axis and is controlled by the at least one motor, wherein the valve disk can be moved relative to the valve seat with the guide element.

[0057] The position of the longitudinal axis is defined in particular by the extent of the guide element, which is designed or referred to as a push rod or guide rod, for example, and / or by the linear movement direction provided by the drive unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Hereinafter, the device of the present invention will be described in detail by way of example in conjunction with a specific embodiment schematically shown in the figure. Herein, other advantages of the present invention are also introduced, specifically showing that:

[0059] Figure 1a to Figure 1b A first embodiment of the vacuum regulating valve of the present invention is shown in cross-section in a closed position and an open position;

[0060] Figure 2a to Figure 2bA first embodiment of the vacuum regulating valve of the present invention is shown in a top view in an open position and a closed position;

[0061] Figure 3 A second embodiment of the vacuum regulating valve of the present invention is shown;

[0062] Figure 4a to Figure 4b A third embodiment of the vacuum regulating valve of the present invention is shown in cross-section in an open position and a closed position;

[0063] Figure 5a to Figure 5b A third embodiment of the vacuum regulating valve of the present invention is shown in a top view in an open position and a closed position;

[0064] Figure 6 A third embodiment of the vacuum regulating valve of the present invention is shown in a three-dimensional diagram;

[0065] Figure 7 shows another embodiment of the vacuum regulating valve of the present invention connected to a process chamber; and

[0066] Figure 8 Another embodiment of the vacuum regulating valve of the present invention is shown connected to a process chamber having an asymmetric chamber interior structure. DETAILED DESCRIPTION

[0067] Figure 1a A cross section through an embodiment of a vacuum control valve according to the invention is schematically shown in the closed position. Figure 2a The embodiment of the vacuum control valve 10 is shown in a top view, also in the closed position. Figure 1b and Figure 2b The embodiment of the vacuum control valve 10 is shown in the open position.

[0068] The regulating valve 10 has three valve sub-openings, of which only two 11a and 11b are shown in the cross-sectional view. Figure 2a and Figure 2b The arrangement of all three sub-openings as well as the associated valve disk and valve seat can be seen in FIG.

[0069] In the following, with respect to the third valve opening, sometimes representative reference is also made to the first and second valve discs, the valve seat and the components connected thereto. The design of the third valve opening is basically similar to the other two.

[0070] The valve sub-openings 11a to 11c are arranged symmetrically about the central axis Z of the valve 10. The central axis Z is defined by the flow center of the valve 10. The flow center in turn corresponds to the geometric center of the flow path or flow channel jointly provided for the fluid through the valve sub-openings.

[0071] The vacuum regulating valve 10 has a first valve seat, a second valve seat and a third valve seat. The three valve seats each have a valve opening 11a to 11c, which are surrounded by respective sealing surfaces 12a to 12c. A first valve disc 13a, a second valve disc 13b and a third valve disc 13c are provided corresponding to the valve seats. The valve discs 13a to 13c are designed so that their contact surfaces 14a to 14c (disc-side sealing surfaces) correspond to the sealing surfaces 12a to 12c of the valve seats. The contact surfaces have substantially the same shape and spatial extension range according to the respective sealing surfaces.

[0072] Each valve disk 13a to 13c has a sealing means at its contact surface 14a to 14c, in particular a seal in the form of an O-ring or a sulphurized polymer, in particular a fluorinated polymer. Figure 1b Such a seal on the contact surface 14b can be seen in FIG. According to an alternative embodiment, the sealing means is alternatively or additionally arranged on the side of the sealing surfaces 12a to 12c.

[0073] According to this embodiment, a corresponding number of drive components 15a to 15c are provided corresponding to the number of valve disks, which together form a drive unit of the valve 10. Each drive component 15a to 15c is connected to one valve disk 13a to 13c by means of a connecting rod.

[0074] The drive components 15a to 15c are designed in such a way that the linear mobility of the valve discs 13a to 13c along the axes defined by the extension range of the respective connecting rods is provided. The drive mechanism is designed, for example, as a linear motor or a stepper motor. The orientation of the valve discs 13a to 13c or the contact surfaces 14a to 14c is parallel to the orientation of the valve seats or the sealing surfaces 12a to 12c in both the open state and the closed state.

[0075] In the embodiment shown, each valve disk 13a to 13c is assigned a motor 15a to 15c. In an alternative embodiment (not shown here), only one motor can be provided, which is connected to all valve disks by means of a connecting unit. The connecting unit can have, for example, a hinge, a shaft and / or a transmission mechanism, etc. The valve can thus be opened or closed by opening and closing the valve sub-openings simultaneously.

[0076] The three valve seats are arranged obliquely relative to each other. Each sealing surface 12a to 12c defines a sealing plane by its shape and extension.

[0077] The valve seats are particularly oriented such that the respective sealing planes contain different sides of a virtual, particularly ordered or straight pyramid with a polygonal base. In other words, each side of the virtual pyramid with a polygonal base is located in one of the sealing planes. In the embodiment shown, the base of the pyramid is triangular.

[0078] This arrangement of several valve sub-openings 11a to 11c offers the advantage that the mechanism for providing the open state and the closed state is less complex. The linear movement of the disks 13a to 13c, which can be precisely controlled by means of the drive unit, allows, in addition to the opening and closing of the openings 11a to 11c, also the adjustment of a defined opening cross section of one of each individual valve sub-opening 11a to 11c and, therefore, of the total valve opening.

[0079] By, for example, the valve disk gradually approaches the associated valve seat, the opening cross section of the associated valve sub-opening can be reduced gradually, in particular continuously.

[0080] For this purpose, the vacuum control valve 10 also provides the possibility of purposefully regulating the fluid flow through the valve opening. Thus, if a defined internal pressure is to be provided in the process chamber, a defined amount of fluid (mass or volume) flowing out per unit time can be regulated by means of the vacuum control valve 10, which is then preferably connected to the vacuum pump on the one hand and to the process chamber on the other hand. In this case, the pressure in the chamber, which is determined, for example, by means of a pressure sensor, can be considered as a control parameter. Alternatively, the opening cross section can be controllably adjusted and varied according to a predetermined rule.

[0081] The vacuum regulating valve 10 further comprises a first interface 16 and a second interface 17. At least one of the interfaces can be designed as a flange. The valve seat is arranged in the flow path of the flow space connecting the first interface 16 and the second interface 17.

[0082] It should be noted that the present invention does not only cover embodiments with more than three valve openings, valve seats and valve disks, but in particular also encompasses solutions with two valve openings, valve seats and valve disks respectively.

[0083] Figure 3 Another embodiment of the present invention is shown. The vacuum regulating valve also has three valve seats and three corresponding valve discs 23a to 23c, which are provided for regulating the flow rate through the respective valve sub-openings 21a to 21c.

[0084] A first connection 26 , which is opposite to the second connection, provides for the connectability of the valve 20 to, in particular, a pipeline, a process chamber or a vacuum pump.

[0085] Each valve disk 23a to 23c is mechanically connected to a respective drive member 25a to 25c and can therefore be adjusted along a respective linear adjustment axis. The operating principle of opening, interrupting and regulating the flow is therefore similar to that of the previous embodiment.

[0086] Each valve disk 23a to 23c forms a valve assembly with its respective associated drive component 25a to 25c. Each valve assembly therefore has exactly one drive component and one valve disk in addition to other fastening and sealing components. Figure 32 and 3. Reference is made by way of example to a valve assembly 28 consisting of a valve closure 23c and a motor 25c. Similarly, two other such assemblies consist of a combination of a valve closure 23a and a motor 25a and of a combination of a valve closure 23b and a motor 25b.

[0087] like Figure 3 As shown, the vacuum regulating valve 20 is designed in such a way that the valve assembly is replaceable in a modular form. For this purpose, the housing 29 of the valve 20, which includes three valve seats, has recesses on the periphery. Each recess is correspondingly assigned to one of the valve seats and is particularly arranged opposite to the valve seat.

[0088] The recess and the valve component 28 are designed to match each other so that the component 28 can be inserted into the recess and connected to it by means of its fastening elements. This fixing can be carried out, for example, by means of a screw connection or clamping. Preferably, a seal is provided between the contact surface around the recess and the corresponding contact surface of the valve component 28.

[0089] Due to the modular design, defective or worn parts can be replaced relatively easily. For example, seals provided on the side of the valve disks 23a to 23c are subjected to material loads with each movement into or out of the closed position and therefore have to be replaced or refurbished regularly. Due to the advantageous modular design, considerable time savings can be achieved for these maintenance operations compared to conventional valve solutions.

[0090] Figure 4a , Figure 4b and Figure 5a , Figure 5b A third embodiment of the vacuum control valve according to the invention is shown in a cross-sectional view and in a plan view. Figure 4a and Figure 5a The valve is shown in an open position, Figure 4b and Figure 5b The valve is shown in the closed position.

[0091] This embodiment again has three valve seats with respective surrounding sealing surfaces 32a to 32c and respective valve sub-openings 31a to 31c. The valve seats or sealing surfaces 32a to 32c are arranged in the same plane. The valve sub-openings 31a to 31c all have the same shape and size, but are designed to be rotated 120° relative to the respective adjacent openings.

[0092] The vacuum control valve 30 further comprises three valve closing elements 33a to 33c (valve disks) with contact surfaces 34a to 34c, the sealing elements of which cooperate sealingly with the sealing surfaces 32a to 32c of the valve seats in the closed position.

[0093] Each valve closing member 33a to 33c is mounted rotatably around a respective rotation axis. In addition, each valve closing member 33a to 33c is connected to a respective drive member 35a to 35c (motor). With the aid of the motor 35a to 35c, the valve disc 33a to 33c can be controlled to rotate around the rotation axis. The valve closing members 33a to 33c thus function as valve flaps. In this case, the surface defined by the closing side of the respective valve flap and the sealing plane defined by the extension range of the respective sealing surface enclose a variable opening angle α, wherein the respective opening cross section of a valve sub-opening is associated with the respective opening angle α.

[0094] Each motor 35a to 35c is individually controllable. In addition, the vacuum control valve 30 has a control unit or a regulating unit, which cooperates with the motors and is designed in such a way that the motors can be selectively controlled individually or the movement of the valve flaps 33a to 33c can be synchronized by corresponding control. For this purpose, the control unit or the regulating unit has corresponding algorithms and functionality. Thus, the valve flaps 33a to 33c can be moved synchronously at the same time, so that they provide the closed position at the same time, for example, when they are moved into the closed position.

[0095] The advantage of the rotatable mounting of the valve closing elements 33a to 33c is that a highly precise fine adjustment function is provided. Unlike a linear valve disc movement, the tilting of the closing elements 33a to 33c allows a very fine adjustment of the valve opening state by means of small opening state change steps, especially at very low pressures, which occur due to the increasing distance of the valve disc from the valve seat at increasing distances from the axis of rotation (when the current opening angle α>0).

[0096] The proposed solution avoids the problem of sudden closing at small opening angles that is common in valves of the prior art by providing a plurality of valve disks and the resulting lower lever forces per valve disk.

[0097] The vacuum regulating valve 30 also has a first interface 36 and a second interface 37. At least one of the interfaces can be designed as a flange. The valve seat is arranged in the flow path of the flow space connecting the first interface 36 and the second interface 37.

[0098] Figure 6 A three-dimensional diagram showing Figure 4a , Figure 4b and Figure 5a , Figure 5b The valve seat is designed such that the valve sub-openings 31a to 31c defined thereby define respective opening axes 39a to 39c, which are oriented parallel to each other. The opening axes 39a to 39c intersect the respective centers of the valve sub-openings 31a to 31c and extend orthogonally to a sealing plane defined by the sealing surfaces 32a to 32c.

[0099] The distribution of the valve overall opening into a plurality of sub-openings also offers the advantage that a plurality of valve closing elements are also provided, and the mass of each individual closing element can be reduced individually. Since the mass to be moved is smaller, a much shorter movement time can thereby be achieved, i.e. the time required to move the valve closing element from the open position to the closed position (or vice versa) can be shortened.

[0100] Figure 7 A processing chamber 40 is shown, which has a gas inlet 41 and a substrate 1 to be processed arranged in the processing chamber 40 .

[0101] According to another embodiment, a vacuum regulating valve 50 according to the present invention having valve sub-openings 51a and 51b connected to the gas outlet is provided on the side of the processing chamber 40 opposite to the gas inlet 41. Each valve opening is provided by a respective valve seat of the vacuum valve 50. Each valve sub-opening 51a, 51b is equipped with a valve closing member 53a, 53b. The two valve closing members 53a and 53b of the valve 50 are designed to be respectively flippable around their respective rotation axes. By moving the valve flaps 53a and 53b, the opening angle and thus the flow rate per unit time can be changed and adjusted.

[0102] The flow of fluid through the process chamber is shown according to the arrows. The specific design of the vacuum regulating valve 50 with the provision of a plurality of valve sub-openings 51a and 51b provides a symmetrical flow of fluid through the valve 50. In addition, a symmetrical (concentric) outflow of fluid from the process chamber 40 can also be achieved by providing a total opening that is symmetrically constructed around the central valve axis Z and is composed of a plurality of sub-openings.

[0103] For processing, the substrate 1 is preferably located on a chuck which allows electrostatic holding of the substrate 1. The flow of the process gas can also be directed concentrically (uniformly) around the chuck by means of symmetrical valve openings.

[0104] This symmetrical, uniform or concentric flow behavior is very advantageous for substrate processing under vacuum or low pressure, because it results in a uniform distribution of the process gas to the substrate, so that, for example, deposition processes or etching processes can be carried out very uniformly and with high quality and reliability.

[0105] Figure 8 An embodiment of a process chamber 40 is shown, which has a gas inlet 41 and a processing device 45 arranged in the process chamber 40 for a substrate to be processed.

[0106] The vacuum regulating valve 50 connected to the gas outlet and having two valve sub-openings 51a, 51b according to the present invention is located on the side of the processing chamber 40 opposite to the gas inlet 41. Each valve opening is provided by a respective valve seat of the vacuum valve 50. Each valve sub-opening 51a, 51b is equipped with a valve core 53a, 53b. The two valve cores 53a, 53b of the valve 50 are designed to be flippable around a respective rotation axis. By adjusting the valve flaps 53a and 53b, the respective opening angles and thus the respective flow rates per unit time can be individually changed and adjusted for each of the valve sub-openings 51a and 51b.

[0107] The processing device 45 is arranged asymmetrically in the process chamber 40. Such an arrangement of the processing device 45 is typical for preparing for the execution of such vacuum processing processes. Here, the processing device 45 is, for example, only fixed to one side of the chamber 40. The processing device 45 is therefore not centrally located in the chamber 40 and the mere placement or fixing causes an asymmetrical flow of fluid through the chamber 40. Here, the processing device 45 is circulated differently by the fluid.

[0108] This asymmetric flow through the chamber 40 can be compensated by means of the vacuum control valve 50 of the invention. By providing different opening states of several valve sub-openings 51a, 51b, the asymmetry associated with the gas flow can be compensated. For this purpose, the valve cores 53a, 53b are placed in different tilting positions (opening angles), thereby providing different opening cross sections. As a result, the fluid no longer flows out centrally through the valve, but is also asymmetrical within the valve about the central axis.

[0109] Because of the different opening states, the fluid flow can be adjusted with different strengths by the direction of the chamber cross section. In other words, the gas flow performance can be adjusted to behave differently in different areas of the chamber, for example, different flow rates can be adjusted at opposite chamber walls.

[0110] Because of this variable adjustment of the fluid flow through the valve, the non-uniform and varying flow characteristics caused by the process device 45 can be compensated so that the resulting annular flow of the process device 45 is symmetrical (uniform).

[0111] Obviously, the figures shown only schematically represent possible embodiments. According to the invention, the various approaches can also be combined with one another and with prior art methods and devices for regulating volume flows or pressures in a process volume under vacuum conditions.

Claims

1. A vacuum regulating valve (10, 20, 30, 50), the vacuum regulating valve being used for adjusting a volume flow or a mass flow and for interrupting a flow path in an airtight manner, the vacuum regulating valve comprising: - a first valve seat having a first valve opening (11a, 21a, 31a, 51a) defining a first opening axis (39a) and a first sealing surface (12a, 32a) surrounding the first valve opening (11a, 21a, 31a, 51a); - a first valve disc (13a, 23a, 33a, 53a), the first valve disc (13a, 23a, 33a, 53a) having a first contact surface (14a, 34a) corresponding to the first sealing surface (12a, 32a); - a drive unit, which is designed and connected to the first valve disk (13a, 23a, 33a, 53a) so that the first valve disk can be moved from an open position to a closed position and back, in which the first valve disk (13a, 23a, 33a, 53a) and the first valve seat are not in contact with each other, in which an axial sealing contact exists between the first sealing surface (12a, 32a) and the first contact surface (14a, 34a) by a seal located therebetween, and the first valve opening (11a, 21a, 31a, 51a) is thereby hermetically closed, Its characteristics are: The vacuum regulating valve (10, 20, 30, 50) at least comprises: - a second valve seat having a second valve opening (11b, 21b, 31b, 51b) defining a second opening axis (39b) and a second sealing surface (12b, 32b) surrounding the second valve opening (11b, 21b, 31b, 51b); - a second valve disc (13b, 23b, 33b, 53b), the second valve disc (13b, 23b, 33b, 53b) having a second contact surface (14b, 34b) corresponding to the second sealing surface (12b, 32b), wherein the total valve opening of the vacuum regulating valve is formed by at least the first valve opening (11a, 21a, 31a, 51a) as the first valve sub-opening and the second valve opening (11b, 21b, 31b, 51b) as the second valve sub-opening, and the first valve seat and the second valve seat are arranged inclined relative to each other, so that the plane defined by the first sealing surface and the plane defined by the second sealing surface each contain a side surface of a virtual pyramid.

2. The vacuum regulating valve (10, 20, 30, 50) according to claim 1, Its characteristics are: The vacuum regulating valve (10, 20, 30, 50) has: - a third valve seat having a third valve opening (11c, 21c, 31c) defining a third opening axis (39c) and a third sealing surface (12c, 32c) surrounding the third valve opening (11c, 21c, 31c), and - a third valve disc (13c, 23c, 33c), the third valve disc having a third contact surface (14c, 34c) corresponding to the third sealing surface (12c, 32c), The valve main opening is further formed by the third valve opening (11c, 21c, 31c) serving as a third valve sub-opening.

3. The vacuum regulating valve (10, 20, 30, 50) according to claim 2, Its characteristics are: The drive unit is connected to the second valve disc (13b, 23b, 33b, 53b) so that the connected valve disc can at least be moved from the respective open position to the closed position and back, in which the corresponding valve disc and the corresponding valve seat are not in contact with each other, and in which the corresponding sealing surface and the corresponding contact surface have axial sealing contact through the corresponding sealing element located therebetween, thereby closing the corresponding valve sub-opening in an airtight manner.

4. The vacuum regulating valve (10, 20, 30, 50) according to claim 2, Its characteristics are: The vacuum regulating valve (10, 20, 30, 50) has a connecting mechanism, which provides a mechanical connection between the first valve disc (13a, 23a, 33a, 53a) and the second valve disc (13b, 23b, 33b, 53b) and is connected to the drive unit so that the corresponding valve discs can be moved together with the help of the drive unit.

5. The vacuum regulating valve (10, 20, 30, 50) according to claim 1, Its characteristics are: - the drive unit has at least one first drive component (15a, 25a, 35a) and a second drive component (15b, 25b, 35b), and - The first drive member (15a, 25a, 35a) is connected to the first valve disc (13a, 23a, 33a, 53a), and the second drive member (15b, 25b, 35b) is connected to the second valve disc (13b, 23b, 33b, 53b).

6. The vacuum regulating valve (10, 20, 30, 50) according to claim 1, Its characteristics are: The vacuum regulating valve (10, 20, 30, 50) has a control unit, and the drive unit can be controlled according to a control signal provided by the control unit.

7. The vacuum regulating valve (10, 20, 30, 50) according to claim 6, Its characteristics are: Each drive component of the drive unit can be controlled individually by means of the control signal.

8. The vacuum regulating valve (10, 20, 30, 50) according to claim 1, Its characteristics are: The vacuum regulating valve (10, 20, 30, 50) has a first interface (16, 26, 36) and a second interface (17, 27, 37), wherein the first valve seat and the second valve seat are arranged in a flow channel, and the flow channel connects the first interface (16, 26, 36) and the second interface (17, 27, 37).

9. The vacuum regulating valve (10, 20, 30, 50) according to claim 8, Its characteristics are: The drive unit and at least one of the valve discs are designed and matched in such a way that at least one of the valve discs can be adjusted to move to a fine-tuning position, wherein: - at least one of the valve discs is tilted relative to the corresponding valve seat so that the first sealing plane and the second sealing plane enclose a specified angle α, and The seal lies completely against the associated sealing surface or contact surface and only partially against the respective other sealing surface or contact surface.

10. The vacuum regulating valve (10, 20, 30, 50) according to claim 9, Its characteristics are: The drive unit and at least one of the valve discs are designed and connected so that when at least one of the valve discs moves from the open position to the closed position or from the closed position to the open position, the at least one valve disc is in the fine-tuning position before reaching the closed position or before reaching the open position.

11. The vacuum regulating valve (10, 20, 30, 50) according to claim 9, Its characteristics are: - the first sealing surface (12a, 32a) points in a direction parallel to the first opening axis (39a) and extends perpendicularly to the first opening axis (39a), and - at least one of the valve discs is positioned in the fine-tuning position so that a second sealing plane defined by the extension of the contact surface is inclined relative to the opening axis, wherein - the first sealing plane and the second sealing plane enclose a corresponding prescribed angle α>0° in the fine-tuning position, and - The first sealing plane and the second sealing plane are oriented substantially parallel in the closed position.

12. The vacuum regulating valve (10, 20, 30, 50) according to claim 10, Its characteristics are: The second fine-tuning position, several fine-tuning positions or multiple fine-tuning positions of at least one of the valve discs are adjustable, wherein: - Angle α enclosed by the first sealing plane and the second sealing plane n Always different, and The seals each completely rest against the associated sealing surface or contact surface and only partially against the other sealing surface or contact surface.

13. The vacuum regulating valve (10, 20, 30, 50) according to claim 12, Its characteristics are: The fine adjustment positions can be adjusted individually or continuously in a controllable manner and can thus provide control of the volume flow or mass flow of the medium flowing through the valve sub-opening.

14. The vacuum regulating valve (10, 20, 30, 50) according to claim 1, Its characteristics are: At least one of the valve disks can be linearly moved along the adjustment axis.

15. The vacuum regulating valve (10, 20, 30, 50) according to claim 1, Its characteristics are: The first valve opening (11a, 21a, 31a, 51a) and the second valve opening (11b, 21b, 31b, 51b) are symmetrically arranged with the central axis (Z) of the vacuum regulating valve (10, 20, 30, 50) as the center, wherein the central axis (Z) extends through the valve center.

16. The vacuum regulating valve (10, 20, 30, 50) according to claim 1, Its characteristics are: - an opening axis respectively defined by a respective valve opening of the valve seat intersects the center of the respective valve opening and extends orthogonally to a respective sealing plane defined by an extension of the respective sealing surface, and - The corresponding opening axes intersect.

17. The vacuum regulating valve (10, 20, 30, 50) according to claim 2, Its characteristics are: The drive unit is connected to the third valve disk.

18. The vacuum regulating valve (10, 20, 30, 50) according to claim 4, Its characteristics are: The connection mechanism provides a mechanical connection between the first valve disc (13a, 23a, 33a, 53a) and the third valve disc (13c, 23c, 33c) and is connected to the drive unit so that the corresponding valve discs can be moved together by means of the drive unit.

19. The vacuum regulating valve (10, 20, 30, 50) according to claim 17, Its characteristics are: The drive unit has at least one third drive component.

20. The vacuum regulating valve (10, 20, 30, 50) according to claim 5, Its characteristics are: The drive unit has a corresponding motor.

21. The vacuum regulating valve (10, 20, 30, 50) according to claim 19, Its characteristics are: The third driving member is connected to the third valve disc.

22. The vacuum regulating valve (10, 20, 30, 50) according to claim 6, Its characteristics are: The vacuum regulating valve (10, 20, 30, 50) has an adjusting unit.

23. The vacuum regulating valve (10, 20, 30, 50) according to claim 6, Its characteristics are: The drive unit can be controlled as a function of the adjustment variable.

24. The vacuum regulating valve (10, 20, 30, 50) according to claim 8, Its characteristics are: The first valve disc and the second valve disc are at least substantially outside of the flow passage in the open position.

25. The vacuum regulating valve (10, 20, 30, 50) according to claim 8, Its characteristics are: The first valve disc and the second valve disc are completely outside of the flow passage in the open position.

26. The vacuum regulating valve (10, 20, 30, 50) according to claim 9, Its characteristics are: The drive unit and at least one of the valve disks are connected in such a way that at least one of the valve disks can be adjusted to move to a fine-tuning position.

27. The vacuum regulating valve (10, 20, 30, 50) according to claim 12, Its characteristics are: The second fine-tuning position, several fine-tuning positions or multiple fine-tuning positions of at least one of the valve discs are continuously adjustable.

28. The vacuum regulating valve (10, 20, 30, 50) according to claim 12, Its characteristics are: The vacuum regulating valve (10, 20, 30, 50) can be used to adjust and / or regulate the prescribed flow properties.

29. The vacuum regulating valve (10, 20, 30, 50) according to claim 12, Its characteristics are: Overall, a defined flow behavior can be adjusted and / or regulated via the at least two valve openings.

30. The vacuum regulating valve (10, 20, 30, 50) according to claim 28, Its characteristics are: The flow properties can be adjusted in an asymmetrical manner with respect to a central axis (Z) of the vacuum regulating valve (10, 20, 30, 50), wherein the central axis (Z) extends through the valve center.

31. The vacuum regulating valve (10, 20, 30, 50) according to claim 13, Its characteristics are: The fine adjustment positions can be adjusted individually or continuously in a controllable manner and thus can provide a continuous control of the volume flow or mass flow of the medium flowing through the valve sub-opening.

32. The vacuum regulating valve (10, 20, 30, 50) according to claim 2, Its characteristics are: The first valve opening (11a, 21a, 31a, 51a) and the third valve opening are symmetrically arranged with the central axis (Z) of the vacuum regulating valve (10, 20, 30, 50) as the center.

33. The vacuum regulating valve (10, 20, 30, 50) according to claim 17, Its characteristics are: The respective opening axes intersect at a common intersection point.

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