Vacuum angle valve with pressure sensor

Abstract

A vacuum valve (10) for gas-tight blocking of a flow passage, comprising a valve housing (11) having a first connection (12) in the direction of a first axis (12'), a second connection (13) in the direction of a second axis (13') and a valve seat (16). The vacuum valve (10) further comprises a valve plate (17), a drive unit (30) by means of which a controlled movement of the valve plate (17) along the first axis (12') or perpendicular to the first axis (12') can be provided, and a control unit (40) for controlling the movement of the valve plate (17). The vacuum valve (10) comprises a pressure sensor (50) arranged to be able to measure the process pressure present in the flow chamber. The control unit (40) has a process control function, which is configured to process provided process information, measure the process pressure present in the flow chamber (15) by the pressure sensor (50), and control the movement of the valve plate (17) in response to the processed process information and the process pressure, when performing this process control function.

Description

[Technical field]

[0001] The present invention relates to a vacuum angle valve with a pressure sensor for substantially gas-tight blocking of a flow passage between two connections arranged in an angle.

[0002] Valves of the type mentioned at the outset are known from the prior art in various different embodiments. Vacuum valves are used in particular in the field of IC and semiconductor manufacturing, which must take place in a protected atmosphere and as far as possible without the presence of contaminating particles.

[0003] A valve known from the prior art, for example as described in US Pat. No. 6,772,989, has a valve body with two connections arranged perpendicular to one another, a valve seat arranged in a flow chamber in a passage connecting the two connections, and an opening located opposite the valve seat. A piston of a pneumatic cylinder system is arranged in a valve cover which closes the opening. Via a valve rod, the piston drives a valve plate which opens and closes the valve seat. The valve cover is attached to the opening in a gas-tight manner by a bellows plate. A return spring between the valve plate and the valve cover is compressed when the valve seat opens, so that the valve closes under spring force.

[0004] The valve cover has connections for feeding and withdrawing pressurized air into and from a pressure chamber defined by the piston on the side of the bellows plate. Both ends of the bellows surrounding the valve rod are gas-tightly attached to the inner edge surface of the bellows plate and to the valve plate. The valve plate has an annular retaining groove on its surface facing the valve seat, in which a sealing ring is arranged.

[0005] The valve housing is usually made of aluminum or special steel or is internally coated with aluminum or another suitable material, while the valve plate and the bellows are often made of steel. The bellows, which can expand and contract in its longitudinal axis within the displacement stroke of the plate, seals the flow chamber airtight from the return spring, the valve rod and the pressure chamber. Two types of bellows are used in particular: diaphragm bellows and corrugated bellows. The corrugated bellows have the advantage over the diaphragm bellows in that they have no welded seams and can be cleaned more easily, but they have a smaller maximum stroke.

[0006] From WO 2006 / 045317, another angle valve is known. This known angle valve has a manually operable mechanism for opening and closing the valve. From the inside of this mechanism, a lever that can be rotated, for example, by 180° projects and is connected to an internal slider that is also pivotally supported. The opening and closing of the valve can be achieved by the movement of the lever and the cooperation of the slider with an element that is driven by the slider. Due to its specific design, the system has a relatively large area that forms the connection of the internal mechanism to the environment (a slit in the housing for moving the lever).

[0007] Furthermore, angle valves as mentioned at the beginning are known, which have a motor for moving a valve plate, with different mechanisms and transmissions being known which are able to convert the rotary motor movement into a linear movement for opening and closing the valve plate.

[0008] A common drawback of the above-mentioned vacuum angle valves when used in vacuum technology is the relatively rough controllability of the defined valve opening state, which can result, for example, in relatively rapid valve opening, which also becomes important if the valve is used, for example, for the control of different process steps with different process gases and pressures.

[0009] Excessively rapid opening and closing of the valves can result in fluid flows into and out of the process chamber that, rather than having predominantly laminar or uniform flow characteristics, can cause vortex formation within the process volume, which must be avoided, particularly in vacuum applications, because it can cause particles to dissociate and distribute within the process volume, which can lead to undesired contamination of the substrate.

[0010] In order to allow not only rapid flushing of the process chamber but also slow opening and closing movements with small opening cross sections, solutions are known in the prior art in which two separate angle valves are provided for each control section.

[0011] SUMMARY OF THE PRESENT EMBODIMENT It is therefore an object of the present invention to provide an improved angle valve for use in vacuum areas which overcomes the above-mentioned drawbacks.

[0012] In particular, it is an object of the present invention to provide a vacuum angle valve having improved accuracy and reliability for controlling different processes or process steps.

[0013] A further object is to provide a vacuum valve which allows precise and reliable overall control of the different process steps.

[0014] These objects are achieved by implementing the features stated in the characterizing part of the independent claims.Alternative or advantageous refinements of the invention can be found in the dependent claims.

[0015] The idea of ​​the invention is based on the integration of a pressure sensor in a vacuum valve and an open-loop or closed-loop control of the valve based on pressure information from a flow path that can be blocked by the valve.

[0016] The combination of an integrated pressure sensor in a vacuum valve allows for a direct process-dependent valve control. No further control or measuring components are required for this. The control of the vacuum valve can be individually adapted to the process and its parameters (e.g. desired pressure profile, type of process gas used, mass flow rate for the process gas, etc.). In this case, the valve according to the invention only needs to be provided with, for example, corresponding process settings, on the basis of which the valve provides the desired pressure profile.

[0017] The invention accordingly relates to a vacuum valve for gas-tight blocking of a flow path, which comprises a valve housing having a first connection in the direction of a first axis, a second connection in the direction of a second axis and a valve seat which is arranged in the flow path of a flow chamber which connects the first and second connections to one another. In particular, the second axis can run parallel to the first axis or (in particular in the configuration as an angle valve) can run substantially perpendicular to the first axis.

[0018] The connection has, for example, a circular cross section. The flow chamber is in particular a section of the valve which is flushable with fluid from at least one of the two connections in the closed or open state of the valve.

[0019] The valve further comprises a valve plate, e.g. a cylindrical piston, which is axially guided and movable at least partially inside the flow chamber along a first axis (axis of movement) or perpendicular to the first axis (axis of movement) through a defined displacement stroke perpendicular to the surface of the valve seat.

[0020] By the movement of the valve plate, a closing surface of the valve plate facing the valve seat and having a sealing material or seal, in particular in the form of an O-ring located in the mounting groove, can be brought into contact with the valve seat (closed position, blocking of the flow path) or not (open position, opening of the flow path), whereby the flow path is blocked or opened in a substantially gas-tight manner.

[0021] The closing surface may be formed by an end surface of the valve plate. The closing surface and the surface of the valve seat are formed in such a way that they can in particular lie on top of one another. Preferably, the axis of movement of the valve plate runs perpendicular to both surfaces. Alternatively, however, both surfaces can be formed inclined or uneven. In this case, the closing surface and the surface of the valve seat refer to averaged imaginary surfaces to which the axis runs perpendicularly.

[0022] The advantage of the valve according to the invention is that essentially only the valve housing and the valve plate are directly adjacent to the flow chamber of the valve. The medium flowing through the valve, for example the process gas, is therefore only exposed to the smoothly formable closing surface, the smoothly formable outer surface of the valve member and the inner surface of the valve housing, so that the valve is less prone to contamination and the possible reaction surfaces for the gas are reduced. The valve member can be manufactured in particular from aluminum or special steel or other suitable materials, which makes it possible to use only one type of material in the flow chamber. The risk of undesirable reactions between the valve component and the process gas is therefore reduced. Furthermore, a relatively large proportion of the volume of the flow chamber is directly involved in the flow, which leads to low flow losses.

[0023] The valve further comprises a drive unit which is connected to the valve plate in such a way that the drive unit provides a controlled movement of the valve plate along the first axis or perpendicular to the first axis, such that the opening and closing of the valve can be controlled and thus precisely performed by a defined control of the drive unit.

[0024] The drive unit may for example comprise an electric motor or a servo-pneumatic drive which may be coupled to the valve plate such that the electric motor or servo-pneumatic drive can provide a controlled movement of the valve plate along the first axis.

[0025] The vacuum valve further comprises a control unit for controlling the movement of the valve plate.

[0026] The vacuum valve further comprises a pressure sensor arranged to measure the process pressure present in the flow chamber, thereby providing information regarding the pressure of the fluid in the flow chamber.

[0027] The control unit has a process control function for controlling a process step, the process control function being configured to process provided process information, measure a process pressure present in the flow chamber by a pressure sensor, and control movement of the valve plate in response to the processed process information and the process pressure during the execution of the process control function.

[0028] For this purpose, the pressure sensor is connected to the control unit, in particular for transmitting a pressure signal, pressure value or pressure information.

[0029] In other words, this allows the vacuum valve to measure the pressure of a fluid (e.g., process gas) present in the flow chamber and to control the open / closed state of the valve based on the measured pressure. The integrated construction of the valve, i.e., by locating a pressure sensor directly on or within the valve, provides a compact valve solution that allows closed-loop control based pressure adaptation and pressure control in a process chamber connected to the flow chamber (e.g., via a first connection).

[0030] In one embodiment, the process control function may be configured such that the movement of the valve plate occurs continuously and / or according to an amount of time, which may be, for example, a time stamp associated with a defined process pressure at a given process step.

[0031] Alternatively or additionally, the process information may comprise a target closed-loop control curve, which may define a target pressure for a process step as a function of the process time, whereby in particular the target closed-loop control curve provides a desired profile of the pressure change for a certain process step or the process information defines a target pressure profile for at least some of the process steps.

[0032] In one embodiment, the process information may include information regarding the process gas provided within the flow chamber, which may provide, among other things, the type of gas or the flow rate for the process gas.

[0033] According to one embodiment, the process control function may be configured such that a movement speed for movement of the valve plate (along the first axis or perpendicular to the first axis) is adjustable or adjusted in response to process information.

[0034] In particular, the process control function may be configured such that the valve plate is moved or movable at different speeds during each process step.

[0035] Based on this information, one or more pressure changes during a given process step can be controlled and / or closed loop controlled. Correspondingly, the vacuum valve can provide different pressure change rates for a given process step.

[0036] In one embodiment, the process step may include, for example, a venting process for a process chamber connected to a vacuum valve. In this case, the process information may provide a venting pressure profile for the venting process. The drive unit may be controlled by the process control function such that in the first venting section, the movement of the valve plate is performed from the closed position to the first open position with a first movement speed, and in the second venting section, the movement of the valve plate is performed from the first open position to the second open position with a second movement speed, in this case, the first movement speed is lower than the second movement speed, and the first open position provides a smaller opening cross section than the opening cross section of the second open position.

[0037] In this way, a stepped opening of the valves can be provided, with different opening speeds allowing a uniform and as uniform as possible venting of the process chamber, which makes it possible in particular to avoid the generation of fluid eddies in the process volume and thus particle transport.

[0038] Of course, ventilation may take place in more than two ventilation sections, each at different and distinct travel speeds.

[0039] Correspondingly, alternatively, evacuation of the process chamber may be realized. In this case, the process step may include an evacuation process for a process chamber connected to a vacuum valve. The process information provides an evacuation pressure profile for the evacuation process. The drive unit may be controlled by the process control function such that in the first evacuation section, a movement of the valve plate is performed from the third open position to the fourth open position with a third movement speed, and in the second evacuation section, a movement of the valve plate is performed from the fourth open position to the closed position with a fourth movement speed. In this case, the fourth movement speed is lower than the third movement speed, and the fourth open position provides an opening cross section that is smaller than the opening cross section of the third open position.

[0040] Of course, even in this configuration, evacuation may occur in more than two evacuation sections, each at different and distinct travel speeds.

[0041] In one embodiment, the valve housing may have a cavity, in particular a cavity oriented toward the flow chamber, and the pressure sensor may be disposed within the cavity.

[0042] In particular, the cavity may comprise or be provided by a passage or hole.

[0043] In particular, the cavity may connect the flow chamber with the valve outer surface, and the pressure sensor may be arranged on the valve outer surface and connected to the cavity. This allows the pressure sensor to provide a pressure measurement in the flow chamber, while the sensor itself is not present in the flow chamber. This arrangement makes it possible to avoid undesirable jams in the flow chamber, which could lead to turbulence when the process gas flows around it.

[0044] In one embodiment, the vacuum valve may have a sleeve shaped and positioned such that an intermediate chamber is formed between a sleeve wall of the sleeve and an inner wall of the valve housing, the sleeve wall having a sleeve cavity that connects the intermediate chamber with the flow chamber.

[0045] The sleeve cavity thereby in particular provides an opening in the sleeve wall through which fluid flow can be permitted The sleeve cavity may be formed in the sleeve wall, for example, as a slit or hole.

[0046] In particular, the cavity of the valve housing may be arranged and shaped in such a way that it connects the pressure sensor with the intermediate chamber formed by the sleeve.

[0047] In particular, the valve housing cavity and the sleeve cavity can be arranged and shaped in such a way that they connect the pressure sensor and the flow chamber, the sleeve cavity can be oriented, for example, towards the side of the valve housing which has the valve housing cavity.

[0048] By arranging such an inner sleeve in the valve housing, for example on the side of the first connection, a uniform fluid flow through the flow chamber can be achieved, while at the same time a pressure measurement can be carried out by means of a pressure sensor.

[0049] The sleeve may be pressed into the flow chamber, in particular through one of the connections. In this case, the sleeve may extend up to the valve seat or close to the valve seat. In particular, if it extends up to the valve seat, the intermediate chamber can be defined or closed on one side by the valve plate in the closed position.

[0050] In one embodiment, the length of the flow section in the intermediate chamber from the sleeve cavity to the cavity may be in the range of 20 to 40 times the width of the intermediate chamber, the width of the intermediate chamber corresponding in particular to the distance from the inner wall of the valve housing to the sleeve or to the opposite sleeve wall, in other words the flow section is at least 20 times longer than the width of the intermediate chamber.

[0051] The device according to the invention is explained in more detail below, purely by way of example, on the basis of an exemplary embodiment shown diagrammatically in the drawing, whereby further advantages of the invention are also explained. [Brief description of the drawings]

[0052] [Figure 1] FIG. 1 shows a first embodiment of an angle valve according to the present invention. [Diagram 2] FIG. 2 is a cross-sectional view showing an angle valve and a pressure sensor according to the present invention. [Diagram 3] FIG. 2 is a partially enlarged cross-sectional view showing an angle valve and a pressure sensor according to the present invention. [Figure 4a] 1A-1D show different pressure profiles for evacuating a process chamber. [Figure 4b] 1A-1D show different pressure profiles for venting a process chamber. [Diagram 5] FIG. 13 illustrates another embodiment of an angle valve according to the present invention.

[0053] FIG. 1 shows a valve 10 according to the invention which is configured as an angle valve.

[0054] The angle valve 10 comprises a valve housing 11 with a first connection 12 and a second connection 13. The connections 12, 13 are oriented substantially perpendicular to one another. Accordingly, the first connection 12 defines a first axis 12' and the second connection 13 defines a second axis 13'. These axes 12', 13' also extend perpendicularly relative to one another in a corresponding manner. The axis intersection is located inside the housing 11.

[0055] Both connections 12, 13 define a flow path for a medium or fluid (e.g. process gas). This flow path extends through a flow chamber 15 that connects both connections 12, 13. The flow path can be blocked or opened by the valve 10.

[0056] The valve comprises a drive unit 30, which in particular comprises a controllable electric motor, the drive shaft of which is structurally connected by a drive mechanism (transmission mechanism) to the valve-closing body 17 (valve plate) of the valve 10. The drive unit 30 in the illustrated embodiment comprises a spindle drive with a threaded rod and a guide element which cooperates with the threaded rod and is movable along the axis 12' by rotation of the threaded rod. The guide element is connected to the valve plate 17.

[0057] A movable valve plate 17 is arranged inside the valve housing 11. This valve plate 17 has a closing surface with a sealing material 18 arranged all around, which is able to provide a gas-tight blocking of the flow passage when it comes into contact with the valve seat 16 on the housing side. The valve plate 17 can be designed, for example, in the form of a piston. The sealing material can, for example, comprise an O-ring or a vulcanized seal made of a fluoropolymer.

[0058] The valve 10 further comprises a bellows 19, which is connected on the one hand to the valve plate 17 and on the other hand to an inner housing part of the valve 10. The bellows 19 can be made of metal as a corrugated or pleated bellows. The bellows 19 provides an atmospheric separation between at least part of the drive unit (e.g. a threaded rod) and the flow chamber 15. This makes it possible to prevent the ingress of particles generated on the drive side into the flow chamber 15.

[0059] The valve 10 further comprises a control unit 40 for controlling the movement of the valve plate 17. The control unit 40 is connected to and controls the electric motor.

[0060] 2, the vacuum angle valve 10 further includes a pressure sensor 50. The pressure sensor 50 is disposed so that the pressure present in the flow chamber can be measured by the pressure sensor (50).

[0061] For this purpose, in one embodiment, the inner wall of the valve 10 can have, for example, a recess in which the sensor can be arranged. Correspondingly, the pressure sensor can be present inside the valve housing.

[0062] In the illustrated embodiment, the valve wall has a cavity 51 in the region of the flow chamber 15 adjacent to the first connection 12. This cavity 51 can also be seen in FIG. 3, which is an enlarged view of a portion of FIG. 2. The cavity 51 is formed as a passage-like wall through-hole and connects the pressure sensor 50 to the flow chamber 15. The pressure sensor 50 itself is arranged in the illustrated configuration in the outer region of the valve 10, i.e. not inside the valve housing 11. The cavity 51 allows atmospheric exchange between the pressure sensor 50 and the flow chamber 15, which can be supplied with process gas.

[0063] An advantage of this arrangement is easy replacement of the pressure sensor 50, for example for routine maintenance or in the event of sensor failure.

[0064] For this purpose, an auxiliary valve may furthermore be arranged (not shown), which may be connected to the fluid-guiding cavity 51 (for example at the end of the cavity 51) or may be arranged in the extension of this cavity. By means of this auxiliary valve, the fluid flow through the cavity 51 (passage) can be blocked, i.e. the cavity 51 can be sealed (gas-tight).

[0065] The pressure sensor 50 is then replaced by, in particular, first closing the auxiliary valve so that the vacuum area (flow chamber 15) is isolated from the outside area, then replacing the sensor and reopening the auxiliary valve, so that the new sensor can again provide a pressure measurement for the flow chamber.

[0066] The pressure sensor 50 may alternatively be arranged in the region of the second connection 13 or in the region of the valve seat 16 and may selectively be arranged inside or outside the valve housing 11 .

[0067] In the illustrated configuration, the vacuum valve 10 further comprises a sleeve 20. However, the invention also relates to an alternative embodiment without such a sleeve 20.

[0068] The connection of the pressure sensor 50 to the flow chamber 15 is provided in the illustrated configuration by means of a sleeve 20. For this purpose, the inner sleeve 20 is shaped in such a way that an intermediate chamber 22 is formed between the inserted sleeve 20 and the inner wall of the valve housing 11 and is adapted to the valve housing 11 with respect to its spatial extension. The pressure sensor 50 is connected to the intermediate chamber 22 by a passage 51.

[0069] The sleeve 20 has a sleeve cavity 21 in the sleeve wall, which provides an opening between the flow chamber 15 and the intermediate chamber 22. The sleeve cavity 21 therefore provides an atmosphere communication connection between the flow chamber 15 and the intermediate chamber 22. The pressure sensor 50 is therefore connected to the flow chamber 15 and can provide a pressure measurement of the pressure created within the flow chamber 15.

[0070] A seal 52 between the sleeve 20 and the connection 12 of the valve 10 provides a gas-tight connection between the sleeve 20 and the valve 10. In the region of the connection 12, the sleeve 20 is form-lockingly connected to the connection 12 or is snapped into the connection 12. This form-locking connection thereby defines an intermediate chamber 22.

[0071] The pressed sleeve 20 provides improved laminar flow of fluid through the flow chamber 15. The placement of the sleeve cavity 21 allows the fluid to be guided uniformly through the flow chamber 15.

[0072] For this purpose, in particular a plurality (at least two) of sleeve cavities can be provided in the sleeve, for example by two sleeve cavities located opposite each other or by a plurality of sleeve cavities distributed over the entire circumference of the sleeve, which can result in a uniform flow through the cross section of the flow chamber 15. This can result in possibly non-laminar flow phenomena being uniformly distributed, but nevertheless can result in an overall improved flow uniformity.

[0073] The sleeve cavity 21 may in particular be shaped in such a way that no or only negligible turbulence occurs due to the interaction between the sleeve cavity 21 and the passing fluid.

[0074] This prevents the sleeve 20 from providing undesirable individual obstructions (transitions between the valve inner wall and the cavity 51) in the inner flow chamber 15, which directly guides the process fluid, within the flow chamber 15, which would result in undesirable asymmetric flow behavior of the fluid.

[0075] 4a and 4b show different pressure / time profiles for an evacuation phase (FIG. 4a) and a vent phase (FIG. 4b) for a process volume.

[0076] Both curves 60a, 60b show typical pressure profiles during chamber evacuation (60a) and chamber venting (60b) with a conventional angle valve according to the prior art, particularly a pneumatically operated valve. As can be seen, a sudden pressure change occurs, especially at the beginning of evacuation or venting, with a more direct and significant pressure reduction during evacuation and an equally direct and clear pressure increase during venting. This sudden and rapid pressure change leads to air turbulence in the chamber, which causes particle shedding and vortex generation. This phenomenon is very detrimental to the processing processes to be carried out in the chamber, since it leads to significant contamination of, for example, wafers.

[0077] Unfavorable pressure transitions result, for example, from the fact that the valve closure body of prior art valves is typically moved at a non-variable speed throughout its displacement stroke.

[0078] In contrast, the valve of the present invention allows for precise open or closed loop control of the evacuation and venting of the process chamber.

[0079] For this purpose, the control unit 40 of the vacuum valve according to the invention has a process control function for controlling the process steps, in which the process information provided, i.e. for example the setpoint pressure curve for the process step, is processed and the process pressure present in the flow chamber 15 is measured by the pressure sensor 50. A movement of the valve plate 17 is then controlled as a function of the processed process information and the process pressure, i.e. this movement of the valve plate 17 can in particular be performed continuously and in a time-dependent manner.

[0080] Process information provided as a target closed loop control curve may, for example, define a target pressure for a process step as a function of process time.

[0081] Furthermore, the process information may comprise information regarding the process gas provided in the flow chamber 15. Since different process gases have different (flow) properties, this information can directly and significantly influence the mass flow rate through the valve 10 and thus the pressure profile to be adjusted. Corresponding consideration is therefore advantageous.

[0082] As shown by way of example by the curves 61a, 61b, the exhaust (61a) and venting (61b) by the valve according to the invention can be effected in such a way that the pressure changes, especially in the range of a very small valve opening cross section (i.e. near the complete closing of the valve opening or immediately after the slight opening of the valve opening), can be produced relatively uniformly, slowly and in a controlled manner. For this purpose, the valve plate 17 can be moved relatively slowly relative to the valve seat 16.

[0083] Such a uniform transition may then be followed by a more rapid displacement of the valve plate 17 before (particularly for evacuation of the chamber) or after (particularly for venting the chamber) such that, for example, a desired (complete) venting can be provided within a desired process time.

[0084] The variability in the displacement (e.g., speed) of the valve plate 17 allows such a valve according to the present invention to be used in place of the multiple prior art valves required to accommodate such pressure transitions. A typical prior art process would require, for example, a first valve to only slightly pre-vent the chamber and a second valve to provide a quick, complete venting of the chamber.

[0085] The illustrated exhaust or venting may in particular be performed as a closed-loop control of the valve position (position relative to the valve plate along the first axis or orthogonal to the first axis) as a function of the measured pressure. For this purpose, the process information may indicate, for example, a desired valve position for a defined pressure, which then occurs at the pressure thus measured.

[0086] Alternatively, the process information may provide a desired closed-loop control curve (pressure progression over a predefined time interval) and the valve plate may be controlled based on the measured pressure and the (already elapsed) process time, in particular in such a way that the pressure change caused by the displacement of the valve plate follows or provides a predefined pressure progression (closed-loop control curve) over time.

[0087] Such closed-loop control capability provides improved, more flexible and more accurate pressure regulation by the vacuum valve: pressure and pressure profiles can be precisely and individually adjusted or closed-loop controlled for different process steps (different fluids and pressure profiles) depending on the process with a single valve.

[0088] FIG. 5 shows another embodiment of a vacuum valve 10 according to the present invention.

[0089] In contrast to the angle valve 10 according to the invention shown in Fig. 1, in this embodiment the sleeve 20 has a further seal 23, which provides a seal against the inner wall of the valve housing 11. As a result, an intermediate chamber 22 can be defined. The seal 23 thereby separates the intermediate chamber 22 in the direction of the valve seat 16. As a result, the intermediate chamber 22 is not part of the flow chamber 15, i.e. the fluid flowing through the valve does not flow through the intermediate chamber 22, but it is used as a connecting chamber for the pressure sensor 50.

[0090] The arrangement of the sleeve 20, for example as shown in Figure 1 or 5, allows the flow section through which the fluid must flow in the intermediate chamber 22 to the pressure sensor 50 or cavity 51 to be extended. Such an extension of the flow section or flow passage can be advantageous, since the flow velocity of the fluid is reduced, especially due to the increased recessed section at the inner wall of the passage through which the fluid is passed. In this case, the intermolecular forces within the fluid and the frictional forces between the fluid and solid surfaces influence the flow velocity (hydrodynamic boundary layer).

[0091] The section from the sleeve cavity 21 to the opening of the cavity 51 corresponds (at least partially) to the section that the fluid must surmount for the pressure measurement. This section is in particular selected or adjusted in such a way that the flow velocity at the edge of the intermediate chamber 22 when it reaches the opening of the cavity 51 is at least very low or negligible and thus does not lead to a deterioration of the pressure measurement. If the fluid were to flow past the passage opening at a relatively high velocity, the pressure in the passage 22 would decrease and the pressure measurement by the pressure sensor 50 would provide an excessively low value.

[0092] The length of the flow section along the intermediate chamber 22 is in particular selected so that the pressure measured by the sensor 50 corresponds to the chamber internal pressure. In particular, for this purpose the length of the flow section (up to the pressure sensor 50 or to the opening of the cavity 51 into the intermediate chamber 22) corresponds to 20 to 40 times the width of the intermediate chamber 22 (from the sleeve wall to the inner wall of the valve housing 11) or the diameter of the formed flow passage.

[0093] Of course, the illustrated figures only show schematic possible embodiments, and according to the invention different approaches can be combined with each other and with devices for closing process volumes under vacuum conditions of the prior art.

Claims

1. A vacuum valve (10) for gas-tightly blocking a flow path, a valve housing (11) comprising: a first connection part (12) in the direction of a first axis (12'); a second connection part (13) in the direction of a second axis (13'); a valve seat (16) arranged in the flow passage of the flow chamber (15) connecting the first connection (12) and the second connection (13) to each other; a valve housing (11) comprising: a valve plate (17) that is axially guided and movable at least partly inside the flow chamber along the first axis (12′) perpendicular to the plane of the valve seat (16) by a predetermined displacement stroke, so that a closing surface of the valve plate (17) facing the valve seat (16), in particular having a sealing material (18), can be brought into a closed position and contact the valve seat (16) in order to gas-tightly block the flow path, and can be brought into an open position without contact with the valve seat (16) in order to open the flow path; a drive unit (30) coupled to said valve plate (17) such that said drive unit (30) can provide controlled movement of said valve plate (17) along said first axis (12′) or orthogonal to said first axis (12′); a control unit (40) for controlling said movement of said valve plate (17); A vacuum valve (10) comprising: the vacuum valve (10) has a pressure sensor (50) arranged to measure the process pressure present in the flow chamber; the control unit (40) has a process control function for controlling a process step, the process control function performing the process control function: - Process the process information provided; measuring the process pressure present in the flow chamber (15) by the pressure sensor (50); - controlling the movement of the valve plate (17) in response to the processed process information and the process pressure. It is configured as follows: A vacuum valve (10).

2. 2. The vacuum valve (10) according to claim 1, characterized in that the drive unit (30) comprises an electric motor connected to the valve plate (17) in such a way that the electric motor can provide a controlled movement of the valve plate (17) along the first axis (12') or perpendicular to the first axis (12').

3. 3. The vacuum valve (10) according to claim 1 or 2, characterized in that the process control function is configured so that the movement of the valve plate (17) occurs continuously and / or according to a time amount.

4. 3. The vacuum valve (10) of claim 1 or 2, wherein the process information comprises a target closed-loop control curve, the target closed-loop control curve defining a target pressure for the process step as a function of process time.

5. 3. The vacuum valve (10) according to claim 1 or 2, characterized in that the process information defines a target pressure profile for at least part of the process step.

6. 3. The vacuum valve (10) according to claim 1 or 2, characterized in that the process information comprises information about a process gas provided in the flow chamber (15).

7. 3. The vacuum valve (10) according to claim 1 or 2, characterized in that the process control function is configured such that a movement speed for the movement of the valve plate (17) is adjustable depending on the process information.

8. 3. The vacuum valve (10) according to claim 1 or 2, characterized in that the process control function is configured such that the valve plate (17) is moved at different speeds during each of the process steps.

9. the process step includes venting a process chamber connected to the vacuum valve (10); the process information provides a ventilation pressure profile for the ventilation process; the drive unit (30) by means of the process control function - in a first venting section, the movement of said valve plate (17) from said closed position to a first open position is performed at a first speed of movement; In a second venting section, the movement of the valve plate (17) from the first open position to the second open position occurs at a second movement speed. It is controlled as follows: The first speed of movement is lower than the second speed of movement, and the first open position provides a smaller open cross section than the second open position.

3. A vacuum valve (10) according to claim 1 or 2, characterized in that it comprises:

10. the process step includes an evacuation of a process chamber connected to the vacuum valve (10); the process information provides an exhaust pressure profile for the exhaust process; the drive unit (30) by means of the process control function in the first exhaust section, the movement of said valve plate (17) from the third open position to the fourth open position occurs at a third speed of movement; In the second exhaust section, the movement of the valve plate (17) from the fourth open position to the closed position occurs at a fourth speed of movement. It is controlled as follows: The fourth speed of movement is lower than the third speed of movement, and the fourth open position provides a smaller open cross section than the open cross section of the third open position.

3. A vacuum valve (10) according to claim 1 or 2, characterized in that it comprises:

11. The valve housing (11) has a cavity (51), in particular a passage or hole, the cavity connects the flow chamber (15) with the valve exterior surface; the pressure sensor (50) is located on the outer surface of the valve and is connected to the cavity (51); 3. A vacuum valve (10) according to claim 1 or 2, characterized in that it comprises:

12. The vacuum valve (10) has a sleeve (20), the sleeve (20) is shaped and arranged so that an intermediate chamber (22) is formed between the sleeve wall of the sleeve (20) and the inner wall of the valve housing (11); - said sleeve wall has a sleeve cavity (21); The sleeve cavity (21) connects the intermediate chamber (22) and the flow chamber (15).

3. A vacuum valve (10) according to claim 1 or 2, characterized in that it comprises:

13. The valve housing (11) has a cavity (51), in particular a passage or hole, 13. The vacuum valve (10) according to claim 12, wherein the cavity (51) is arranged and shaped to connect the pressure sensor (50) and the intermediate chamber (22).

14. The valve housing (11) has a cavity (51), in particular a passage or hole, The vacuum valve (10) according to claim 12, characterized in that the length of the flow section in the intermediate chamber (22) from the sleeve cavity (21) to the cavity (51) is in the range of 20 to 40 times the width of the intermediate chamber (22).

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