Vacuum angle valve comprising a pressure sensor

Abstract

The invention relates to a vacuum valve (10) for interrupting a flow path in a gas-tight manner, said vacuum valve comprising a valve body (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 also has: a valve plate (17); a drive unit (30), wherein a controlled displacement of the valve plate (17) along or orthogonal to the first axis (12') can be provided by means of the drive unit (30); and a control unit (40) for controlling the displacement of the valve plate (17). The vacuum valve (10) has a pressure sensor (50) positioned in such a way that a process pressure present in the flow chamber can be measured by means of the pressure sensor (50). The control unit (40) has a process control functionality which is designed in such a way that, when it is implemented, a provided item of process information is processed, the process pressure present in the flow chamber (15) is measured by the pressure sensor (50), and the displacement of the valve plate (17) is controlled depending on the processed item of process information and the process pressure.

Description

[0001] Vacuum angle valve with pressure sensor

[0002] The present invention relates to a vacuum angle valve with a pressure sensor for interrupting a flow path between two corner-shaped connections in a substantially gas-tight manner.

[0003] Valves of the type mentioned above are known in various designs from the state of the art. Vacuum valves are used particularly in the field of IC and semiconductor manufacturing, which must take place in a protected atmosphere, ideally free from the presence of contaminating particles.

[0004] A valve known from the prior art and described, for example, in U.S. Patent 6,772,989 has a valve body with two connections arranged perpendicular to one another, a valve seat arranged in a flow path in the flow chamber connecting the two connections, and an opening opposite the valve seat. A piston of a pneumatic cylinder system is arranged in a valve cover closing the opening. This piston drives a valve disk via a valve rod, 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 disk and the valve cover is compressed when the valve seat opens, so that the valve closes under spring force.

[0005] The valve cover has a connection that supplies and discharges compressed air into a pressure chamber located on the bellows plate side, which is defined by the piston. The two ends of a bellows that surrounds the valve rod are attached in a gas-tight manner to the inner edge surface of the bellows plate and to the valve disc. On the surface facing the valve seat, the valve disc has an annular retaining groove in which a sealing ring is arranged.

[0006] The valve body is usually made of aluminum or stainless steel, or has an internal coating of aluminum or another suitable material, while the valve disk and bellows are usually made of steel. The bellows, which can be expanded and compressed along its longitudinal axis within the range of the disk's adjustment travel, seals the flow space airtight from the return spring, the valve stem, and the pressure chamber. Two main types of bellows are used: diaphragm bellows and corrugated bellows, which differ from diaphragm bellows in that they have no welds and are easier to clean, but have a lower maximum stroke.

[0007] Another angle valve is known from WO 2006 / 045317 A1, which has a manually operated mechanism for opening and closing the valve. A lever which can be rotated by, for example, 180° projects from the interior of the mechanism and is connected to an inner link which is also rotatable. The valve can be opened and closed by moving the lever and the interaction of the link with an element following this link. Due to its specific design, the system has a comparatively large area which connects the internal mechanics with the environment (slot in the housing for moving the lever). Angle valves of this type are also known which have a motor for moving the valve disk.

[0008] Different mechanisms and gears are known for converting the rotating motor movement into a linear movement for opening and closing the valve plate.

[0009] A common disadvantage of the above-mentioned vacuum angle valves when used in vacuum technology is the relatively coarse controllability of certain valve opening states. This can, for example, lead to a relatively rapid valve opening. This relatively coarse controllability also becomes relevant when the valve is used to control different process steps with, for example, different process gases and pressures.

[0010] Opening or closing the valve too quickly can result in fluid flows into and out of the process chamber that do not exhibit predominantly laminar or homogeneous flow behavior, but can cause turbulence in the process volume. Turbulence, however, should be avoided, especially in vacuum applications, as this can dislodge particles and distribute them throughout the process volume, thus leading to unwanted substrate contamination.

[0011] To enable both rapid flooding of a process chamber and slow opening or closing movements with small opening cross-sections, solutions are known in the prior art, with two separate angle valves being provided for each control section. The object of the invention is therefore to provide an improved angle valve for use in vacuum applications that overcomes the aforementioned disadvantages.

[0012] In particular, it is an object of the invention to provide such a vacuum angle valve which has improved precision and reliability for the control of different processes or process steps.

[0013] A further task is to provide a vacuum valve with which different process steps can be controlled precisely and reliably.

[0014] These objects are achieved by implementing the characterizing features of the independent claim. Features that further develop the invention in an alternative or advantageous manner can be found in the dependent patent claims.

[0015] The idea of ​​the present invention is based on the integration of a pressure sensor into a vacuum valve and the control or regulation of the valve based on pressure information from the flow path that can be blocked with the valve.

[0016] By integrating the pressure sensor into the vacuum valve, direct, process-dependent valve control can be implemented. No additional control or measurement components are required. The vacuum valve control can be individually adapted to a process and its parameters (e.g., desired pressure profile, type of process gas used, mass flow rate for a process gas, etc.). The valve according to the invention can then, for example, be provided with a corresponding process specification alone, and the valve provides a desired pressure profile on this basis.

[0017] The invention accordingly relates to a vacuum valve for the gas-tight interruption of a flow path, comprising a valve housing. The valve housing has a first connection in the direction of a first axis, a second connection in the direction of a second axis and a valve seat, wherein the valve seat is arranged in the flow path of a flow space and the flow space connects the first connection and the second connection to one another. In particular, the second axis can run parallel or substantially orthogonal (particularly in the case of a design as an angle valve) to the first axis.

[0018] The connections, for example, have a circular cross-section. The flow space is, in particular, that section of the valve which, when the valve is closed or open, can be flooded with a fluid from at least one of the two connections.

[0019] The valve also has a valve plate, e.g. a cylindrical piston, which is axially displaceable at least partially within the flow space along or orthogonally to the first axis (axis of movement) perpendicular to a surface of the valve seat by an adjustment path.

[0020] By displacing the valve disk, a closure surface of the valve disk facing the valve seat, in particular comprising a sealing material or a sealing body—for example, in the form of an O-ring located in a fastening groove—can be brought into contact with the valve seat (closed position, interrupting the flow path) or brought into external contact (open position, releasing the flow path). As a result, the flow path is either interrupted or released in a substantially gas-tight manner.

[0021] The closure surface can be formed by the end face of the valve disk. The closure surface and the surface of the valve seat are particularly designed such that they can lie on one another. The movement axis of the valve disk preferably runs perpendicular to both surfaces. However, it is alternatively possible for the two surfaces to be inclined or uneven. In this case, the closure surface and the surface of the valve seat are to be understood as virtual, averaged surfaces to which the axis runs perpendicular.

[0022] One advantage of the valve according to the invention is that essentially only the valve housing and the valve disk are directly adjacent to the flow space of the valve. Since only the smooth closure surface, the smooth outer surface of the valve part and the inner surface of the valve housing are exposed to the medium flowing through the valve, such as the process gas, the valve has little tendency to become dirty and the potential reaction surface for the gas is small. The valve part can be manufactured in particular from aluminum or stainless steel or another suitable material, so that it is possible to use only a single material in the flow space. This reduces the risk of unwanted reactions between a valve component and the process gas. Furthermore, the proportion of the volume of the flow space directly involved in the flow is relatively large, so that flow losses are low.

[0023] The valve also has a drive unit coupled to the valve plate in such a way that a controlled displacement of the valve plate along or orthogonally to the first axis can be provided by the drive unit. Thus, the opening and closing of the valve can be controlled and precisely executed by means of a defined control of the drive unit.

[0024] The drive unit can, for example, comprise an electric motor or a servo-pneumatic drive. The electric motor or the servo-pneumatic drive can be coupled to the valve disk in such a way that a controlled displacement of the valve disk along the first axis can be provided by means of the electric motor or the servo-pneumatic drive.

[0025] The vacuum valve also has a control unit for controlling the displacement of the valve plate.

[0026] The vacuum valve further comprises a pressure sensor arranged such that a process pressure present in the flow chamber can be measured by the pressure sensor. The pressure sensor can thus provide information about the pressure of a fluid in the flow chamber.

[0027] The control unit has a process control functionality for controlling a process step. The process control functionality is configured such that, when it is executed, a provided process information is processed, the process pressure present in the flow space is measured by the pressure sensor, and the displacement of the

[0028] Valve disk is controlled depending on the processed process information and the process pressure.

[0029] For this purpose, the pressure sensor is connected in particular to the control unit for transmitting pressure signals, pressure values ​​or pressure information.

[0030] The vacuum valve thus enables measurement of the pressure of the fluid in the flow space (e.g., process gas) and control of the valve's opening or closing state based on the measured pressure. The integrated design of the valve, i.e., the arrangement of the pressure sensor directly on or in the valve, provides a compact valve solution that enables closed-loop pressure adjustment and control in a process chamber connected to the flow space (e.g., via the first connection).

[0031] In one embodiment, the process control functionality can be configured such that the valve disk is moved continuously and / or as a function of a time variable. The time variable can, for example, be a time stamp in a process step that is linked to a specific process pressure.

[0032] Alternatively or additionally, the process information can include a target control curve. The target control curve can define a target pressure for the process step as a function of a process time. In particular, the target control curve thus provides the desired pressure change profile for a process step, or the process information defines a target pressure profile for at least part of the process step.

[0033] In one embodiment, the process information may include information about a process gas provided in the flow chamber. In particular, a type of gas or a flow rate for the process gas may be provided.

[0034] According to one embodiment, the process control functionality can be designed such that a displacement speed for the displacement of the valve disk (along or orthogonal to the first axis) is or is set as a function of the process information.

[0035] In particular, the process control functionality can be configured such that the valve disk is or can be moved at different speeds during the process step.

[0036] Using the above information, a pressure change, even multiple pressure changes, can be controlled and / or regulated during a process step. The vacuum valve can also provide different pressure change rates for a process step.

[0037] In one embodiment, the process step can, for example, comprise a venting process for a process chamber connected to the vacuum valve. The process information can then provide a venting pressure profile for the venting process. The drive unit can be controlled by the process control functionality such that, in a first venting section, the valve disk is moved from the closed position to a first open position at a first displacement speed, and in a second venting section, the valve disk is moved from the first open position to a second open position at a second displacement speed. The first displacement speed is smaller than the second displacement speed, and the first open position provides an opening cross-section that is smaller than an opening cross-section of the second open position.

[0038] This allows for a gradual opening of the valve, whereby the different

[0039] Opening speeds allow for even and as uniform aeration of the process chamber as possible. This can prevent fluid turbulence and thus particle transport in the process volume.

[0040] It is understood that ventilation can take place in more than two ventilation sections with further different displacement speeds.

[0041] Alternatively, an evacuation of the process chamber can be realized. The process step can then comprise an evacuation process for a process chamber connected to the vacuum valve. The process information provides an evacuation pressure profile for the evacuation process. The drive unit can be controlled by the process control functionality in such a way that in a first evacuation section, the valve disk is moved from a third open position to a fourth open position at a third displacement speed, and in a second evacuation section, the

[0042] Valve disc from the fourth open position to the closed position with a fourth

[0043] displacement speed, wherein the fourth displacement speed is smaller than the third displacement speed and the fourth open position provides an opening cross-section which is smaller than an opening cross-section of the third open position.

[0044] Here too, it is understood that the evacuation can take place in more than two evacuation sections with further different displacement speeds.

[0045] In one embodiment, the valve housing may have a recess, in particular a recess facing the flow chamber. The pressure sensor may be arranged in the recess.

[0046] In particular, the recess may have a channel or a bore provided thereby.

[0047] In particular, the recess can connect the flow chamber and the outside of the valve, and the pressure sensor can be arranged on the outside of the valve and connected to the recess. This allows the pressure sensor to provide a pressure measurement in the flow chamber, while the sensor itself is not located in the flow chamber. Such an arrangement avoids unwanted disturbances in the flow chamber, which could lead to flow turbulence when, for example, process gas flows around it.

[0048] In one embodiment, the vacuum valve may comprise a sleeve, wherein the sleeve is shaped and arranged (within the valve housing) in such a way that an intermediate space is formed between a sleeve wall (sleeve outer wall) of the sleeve and an inner wall of the valve housing, the sleeve wall comprises a sleeve recess, and the sleeve recess connects the intermediate space and the flow space.

[0049] The sleeve recess thus provides, in particular, an opening in the sleeve wall and enables fluid flow through the opening. The sleeve recess can, for example, be formed as a slot or hole in the sleeve wall.

[0050] In particular, the recess of the valve housing can be arranged and shaped in such a way that this recess connects the pressure sensor and the space formed by the sleeve.

[0051] In particular, the recess in the valve housing and the sleeve recess can be arranged and shaped such that these recesses connect the pressure sensor and the flow chamber. The sleeve recess can, for example, face the side of the valve housing that has the recess in the valve housing.

[0052] By arranging such an inner sleeve in the valve housing, e.g. on the side of the first connection, a homogeneous fluid flow through the flow space can be achieved, while at the same time a pressure measurement can be carried out by means of the pressure sensor.

[0053] The sleeve can be inserted into the flow chamber, particularly through one of the connections. The sleeve can extend up to or close to the valve seat.

[0054] In particular, when extending to the valve seat, the gap in the closed position can be limited or closed on one side by the valve disk. In one embodiment, a length of

[0055] The flow path in the space from the sleeve recess to the recess should be in a range of 20 to 40 times the width of the space.

[0056] The width of the gap corresponds specifically to the distance from the inner wall of the valve housing to the sleeve or the opposite sleeve wall. In other words, the flow path is at least 20 times longer than the width of the gap.

[0057] The device according to the invention is described in more detail below using specific embodiments schematically illustrated in the drawings, purely by way of example, and further advantages of the invention are also discussed. In detail:

[0058] Fig. 1 shows a first embodiment of an angle valve according to the invention;

[0059] Fig. 2 is a sectional view illustrating the angle valve and the pressure sensor according to the invention; and

[0060] Fig . 3 an enlarged section of the

[0061] Sectional view illustrating the angle valve and the pressure sensor according to the invention;

[0062] Figs. 4a-b different pressure curves for the evacuation and ventilation of the process chamber; and

[0063] Fig. 5 shows a further embodiment of an angle valve according to the invention. Figure 1 shows a valve 10 designed as an angle valve according to the invention.

[0064] The angle valve 10 has a valve housing 11 with a first connection 12 and a second connection 13. The connections 12, 13 are aligned substantially orthogonally to one another. The first connection 12 defines a first axis 12', and the second connection 13 defines a second axis 13', with these axes 12', 13' also being orthogonal to one another. An axis intersection point lies inside the housing 11.

[0065] The two connections 12 and 13 define a flow path for a medium or fluid (e.g., process gas). The flow path extends through a flow chamber 15, which connects the two connections 12 and 13. The flow path can be interrupted or opened using the valve 10.

[0066] The valve has a drive unit 30. The drive unit 30 has, in particular, a controllable electric motor, the drive shaft of which is structurally connected to a valve closure 17 (valve plate) of the valve 10 by means of a drive mechanism (gearbox). The drive unit 30 in the illustrated embodiment has a spindle drive with a threaded rod and a guide element that interacts with the threaded rod and is movable along the axis 12' by rotation of the threaded rod. The guide element is coupled to the valve plate 17.

[0067] The movable valve plate 17 is arranged within the valve housing 11. The valve plate 17 has a closure surface with a circumferentially arranged sealing material 18, by means of which a gas-tight interruption of the flow path can be provided upon contact with a valve seat 16 on the housing side. The valve plate 17 can, for example, be piston-shaped. The sealing material can, for example, comprise an O-ring made of fluoropolymer or a vulcanized seal.

[0068] The valve 10 also has a bellows 19. The bellows 19 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 designed as a metallic corrugated or convoluted bellows. The bellows 19 provides atmospheric separation from at least parts of the drive unit (e.g., threaded rod) and the flow chamber 15. This prevents particles generated by the drive from entering the flow chamber 15.

[0069] The valve 10 also has a control unit 40 for controlling the displacement of the valve plate 17. The control unit 40 is connected to the electric motor to control the motor.

[0070] As also shown in Figure 2, the vacuum angle valve 10 also has a pressure sensor 50. The pressure sensor 50 is arranged such that a pressure present in the flow space can be measured by means of the pressure sensor (50).

[0071] In one embodiment, the inner wall of the valve 10 can, for example, have a recess in which the sensor can be arranged. The pressure sensor can accordingly be located within the valve housing.

[0072] In the embodiment shown, the valve wall in the

[0073] The valve 10 has a recess 51 in the area of ​​the flow chamber 15 adjacent to the first connection 12. This recess is also visible in Figure 3, which shows an enlarged section of Figure 2. The recess 51 is designed as a channel-like wall passage and connects the pressure sensor 50 to the flow chamber 15. The pressure sensor 50 itself is arranged in an external area of ​​the valve 10, i.e., not within the valve housing 11. The recess 51 allows atmospheric exchange between the pressure sensor 50 and the flow chamber 15, in which a process gas can be applied.

[0074] An advantage of this arrangement is the simplified replaceability of the pressure sensor 50, for example in the event of regular maintenance or a defect in the sensor.

[0075] An auxiliary valve (not shown) can also be arranged for this purpose. The auxiliary valve can be connected to the fluid-carrying recess 51 (e.g., at its end) or arranged along this recess. This auxiliary valve can interrupt the flow of fluid through the recess 51 (channel). The recess 51 can thus be sealed (gas-tight).

[0076] The pressure sensor 50 is then replaced in particular by first closing the auxiliary valve so that the vacuum area (flow space 15) is separated from the outside area, then replacing the sensor and reopening the auxiliary valve so that the new sensor can again provide a pressure measurement with respect to the flow space.

[0077] The pressure sensor 50 can alternatively be arranged in the region of the second connection 13 or in the region of the valve seat 16, optionally inside or outside the valve housing 11.

[0078] In the embodiment shown, the vacuum valve 10 further comprises a sleeve 20. However, the invention also relates to alternative embodiments without such a sleeve 20.

[0079] In the illustrated embodiment, the pressure sensor 50 is connected to the flow chamber 15 by means of the sleeve 20. This inner sleeve 20 is shaped and adapted to the valve housing 11 in terms of its spatial extent in such a way that a gap 22 is formed between the inserted sleeve 20 and the inner wall of the valve housing 11. The pressure sensor 50 is connected to the gap 22 via the channel 51.

[0080] The sleeve 20 has a sleeve recess 21 in the sleeve wall. The sleeve recess 21 provides an opening between the flow space 15 and the intermediate space 22. The sleeve recess 21 thus creates an atmospheric communication connection between the flow space 15 and the intermediate space 22. Thus, the pressure sensor 50 is connected to the flow space 15 and can provide a pressure measurement of the pressure prevailing in the flow space 15.

[0081] 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 area of ​​the connection 12, the sleeve 20 is positively connected to the connection 12 or fitted into the connection 12. The intermediate space 22 is thus delimited by this positive connection. The inserted sleeve 20 provides an improved laminar flow of a fluid through the flow space 15. Due to the arrangement of the sleeve recess 21, the fluid can be guided homogeneously through the flow space 15.

[0082] For this purpose, in particular, several (at least two) sleeve recesses can be provided in the sleeve. For example, two opposing sleeve recesses or several such sleeve recesses distributed over the sleeve circumference can lead to a uniform flow across the cross-section of the flow space 15. This allows any non-laminar flow effects to occur in a uniformly distributed manner and thus overall still result in improved flow homogeneity.

[0083] The sleeve recess 21 can in particular be shaped in such a way that no or negligible turbulences arise due to an interaction between the sleeve recess 21 and the fluid flowing past.

[0084] The sleeve 20 thus prevents a single undesired disturbance (transition between the valve inner wall and the recess 51) from occurring within the flow chamber 15, which directly carries a process fluid. Such a single disturbance could cause an asymmetrical, undesired flow behavior of the fluid.

[0085] Figures 4a and 4b show different pressure-time curves for evacuation processes (Figure 4a) and ventilation processes (Figure 4b) for a process volume.

[0086] The two curves 60a and 60b show typical

[0087] Pressure curves during a chamber evacuation ( 60a ) and a

[0088] Chamber ventilation (60b) with a classic angle valve according to the state of the art, in particular with pneumatically operated valves. As can be seen, abrupt pressure changes occur here, particularly when starting the evacuation or ventilation - a more immediate and sharp pressure drop during evacuation and a significant and equally immediate pressure increase during ventilation. These sudden and rapid pressure changes can lead to air turbulence in the chamber and thereby cause particle detachment and eddies. Such effects are very disadvantageous for a processing process carried out in the chamber, since they can result in severe contamination, e.g. of a wafer.

[0089] The disadvantageous pressure curves result, for example, from the fact that a valve closure of a prior art valve is typically moved at a non-variable speed over its entire adjustment range.

[0090] In contrast, the evacuation and ventilation of the process chamber can be precisely controlled and regulated using a valve according to the invention.

[0091] The control unit 40 of the vacuum valve according to the present invention has a process control functionality for controlling a process step. This process control functionality is configured such that, when it is executed, provided process information, for example a target pressure curve for a process step, is processed and the process pressure present in the flow chamber 15 is measured by the pressure sensor 50. The displacement of the valve plate 17 is then controlled as a function of the processed process information and the process pressure. This displacement of the valve plate 17 can therefore occur, in particular, continuously and as a function of a time variable.

[0092] Process information provided as a target control curve can, for example, also define a target pressure for the process step as a function of a process time.

[0093] In addition, the process information may include information about a process gas provided in the flow chamber 15. Since different process gases have different (flow) properties, this information can have a direct and significant influence on the mass flow through the valve 10 and thus on the pressure curve to be set. Therefore, appropriate consideration is advantageous.

[0094] As illustrated by curves 61a and 61b, evacuation (61a) and venting (61b) with a valve according to the invention can be carried out in such a way that a pressure change can be controlled comparatively homogeneously and slowly, particularly in the region of very small valve opening cross-sections (i.e., close to the complete closure of the valve opening or shortly after a slight opening of the valve opening). For this purpose, the valve disk 17 can be moved comparatively slowly relative to the valve seat 16.

[0095] Before (particularly for evacuation of the chamber) or after (particularly for ventilation of the chamber) such a homogeneous transition, a faster adjustment of the valve disk 17 can then follow, whereby, for example, the desired (complete) ventilation can be provided within a desired process time.

[0096] Due to the variability in the adjustment of the valve plate 17 (e.g., speed), a valve according to the invention of this type can replace a plurality of valves that are required according to the prior art for adjusting such a pressure curve. Typical prior art processes, for example, require a first valve for slight pre-ventilation and a second valve for providing rapid, complete ventilation of the chamber.

[0097] The evacuation or venting shown can be carried out, in particular, by controlling valve positions (positions for the valve disk along or orthogonal to the first axis) as a function of a measured pressure. The process information can, for example, indicate a desired valve position for a specific pressure, with this position then being set at such a measured pressure.

[0098] Alternatively, the process information can provide a desired control curve (pressure curve over a period of time), and the valve plate can be adjusted based on the measured pressure and the (already elapsed) process time. This control is performed in particular in such a way that the pressure change caused by the adjustment of the valve plate follows or provides a predetermined pressure curve over time (control curve).

[0099] Such control functionality enables improved, more flexible, and more precise pressure adjustment with a vacuum valve. The pressure and pressure drop can be precisely adjusted or regulated with a single valve, depending on the process (different fluids and pressure profiles), and individually for different process steps.

[0100] Figure 5 shows a further embodiment of a vacuum valve 10 according to the invention.

[0101] In contrast to an angle valve 10 according to the invention as shown in Figure 1, the sleeve 20 here has a further seal 23. The seal 23 provides a seal to the inner wall of the valve housing 11. This allows the intermediate space 22 to be limited. The seal 23 thus separates the intermediate space 22 in the direction of the valve seat 16, whereby the intermediate space 22 is not part of the flow space 15, i.e. a fluid flowing through the valve does not flow through the intermediate space 22, but rather the intermediate space serves as a connecting space for the pressure sensor 50.

[0102] By arranging the sleeve 20, as shown for example in Figure 1 or Figure 5, a flow path along which a fluid has to flow through the intermediate space 22 up to the pressure sensor 50 or up to the recess 51 can be extended. Such an extension of a flow path or of a flow channel can be advantageous because the flow velocity of a fluid decreases with increasing distance covered, particularly on an inner wall of a channel through which the fluid flows. Intermolecular forces within the fluid and frictional forces between the fluid and the solid surface influence the flow velocity (hydrodynamic boundary layer). The path from the sleeve recess 21 to the opening of the recess 51 corresponds (at least partially) to the path that a fluid has to travel for a pressure measurement.The distance is selected or adjusted in particular such that the flow velocity at the edge of the intermediate space 22 upon reaching the opening of the recess 51 is at least very small or negligible, thus preventing any distortion of the pressure measurement. If the fluid were to flow past the channel opening at a comparatively high velocity, the pressure in the channel 22 would drop, and a pressure measurement with the pressure sensor 50 would yield values ​​that are too low.

[0103] The length of the flow path along the intermediate space 22 is selected in particular such that a pressure measured by the sensor 50 corresponds to the internal chamber pressure. In particular, the length of the flow path (up to the pressure sensor 50 or up to the opening of the recess 51 into the intermediate space 22) corresponds to 20 to 40 times the width of the intermediate space 22 (from the sleeve wall to the inner wall of the valve housing 11) or the diameter of a formed flow channel.

[0104] It is understood that the figures shown only schematically represent possible embodiments. The various approaches according to the invention can also be combined with each other and with devices for closing process volumes under vacuum conditions of the state of the art.

[0105] technology can be combined.

Claims

Vacuum valve (10) for gas-tight interruption of a flow path, with • comprising a valve housing (11) ° 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) which is arranged in the flow path of a flow chamber (15), wherein the flow chamber (15) connects the first port (12) and the second port (13) together, • a valve disc (17) which is guided at least partially within the flow space along the first axis (12') perpendicular to a surface of the valve seat (16) and is axially displaceable by an adjustment path such that a closing surface of the valve disc (17) facing the valve seat (16), in particular having a sealing material (18), can be brought into a closed position and thereby into contact with the valve seat (16) to interrupt the flow path gas-tightly and can be provided in an open position without contact with the valve seat (16) to release the flow path, • a drive unit (30) , wherein the drive unit is coupled to the valve disc (17) in such a way that a controlled displacement of the valve disc (17) along or orthogonal to the first axis (12' ) can be provided by means of the drive unit (30), and • a control unit (40) for controlling the displacement of the valve plate (17) , characterized in that • the vacuum valve (10) has a pressure sensor (50) arranged in such a way that a process pressure present in the flow chamber can be measured by means of the pressure sensor (50), • the control unit (40) has a process control functionality for controlling a process step, which is configured such that when it is executed ° a provided process information is processed, ° the process pressure present in the flow chamber (15) is measured by the pressure sensor (50), and The displacement of the valve disc (17) is controlled depending on the processed process information and the process pressure. Vacuum valve (10) according to claim 1, characterized in that the drive unit (30) has an electric motor, wherein the electric motor is coupled to the valve disc (17) such that a controlled displacement of the valve disc (17) along or orthogonal to the first axis (12') can be provided by means of the electric motor. Vacuum valve (10) according to claim 1 or 2, characterized in that The process control functionality is configured such that the displacement of the valve disc (17) occurs continuously and / or as a function of a time interval. A vacuum valve (10) according to one of the preceding claims, characterized in that the process information includes a target control curve and the target control curve defines a target pressure for the process step as a function of a process time. A vacuum valve (10) according to one of the preceding claims, characterized in that the process information defines a target pressure profile for at least a part of the process step. A vacuum valve (10) according to one of the preceding claims, characterized in that the process information includes information about a process gas provided in the flow chamber (15).Vacuum valve (10) according to one of the preceding claims, characterized in that the process control functionality is designed such that a displacement speed for the displacement of the valve plate (17) can be set depending on the process information. Vacuum valve (10) according to one of the preceding claims, characterized in that the process control functionality is configured such that the valve disc (17) is moved at different speeds during the process step. Vacuum valve (10) according to one of the preceding claims, characterized in that • the process step includes a ventilation process for 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) is controlled by the process control functionality in such a way that ° in a first ventilation section, the valve disc (17) is moved from the closed position to a first open position at a first displacement speed and ° in a second ventilation section, the valve plate (17) is moved from the first open position to a second open position at a second movement speed, wherein the first movement speed is smaller than the second movement speed and the first open position provides an opening cross-section that is smaller than an opening cross-section of the second open position. Vacuum valve (10) according to one of the preceding claims, characterized in that • the process step includes an evacuation process for a process chamber connected to the vacuum valve (10), • the process information provides an evacuation pressure profile for the evacuation process, • the drive unit (30) is controlled by the process control functionality in such a way that ° in a first evacuation section, the valve disc (17) is moved from a third open position to a fourth open position at a third movement speed and ° In a second evacuation phase, the valve disc (17) is moved from the fourth open position to the closed position at a fourth displacement speed, wherein the fourth displacement speed is lower than the third displacement speed and the fourth open position provides an opening cross-section that is smaller than the opening cross-section of the third open position. Vacuum valve (10) according to one of the preceding claims, characterized in that the valve housing (11) has a recess (51), in particular a channel or a bore, wherein the recess the flow space (15) and a The outside of the valve connects and • the pressure sensor (50) is arranged on the outside of the valve and connected to the recess (51). Vacuum valve (10) according to one of the preceding claims, characterized in that the vacuum valve (10) has a sleeve (20), wherein • the sleeve (20) is shaped and arranged such that a space (22) is formed between a sleeve wall of the sleeve (20) and an inner wall of the valve housing (11), • the sleeve wall has a sleeve recess (21) and • the sleeve recess (21) connects the intermediate space (22) and the flow chamber (15). Vacuum valve (10) according to claims 11 and 12, characterized in that the recess (51) is arranged and shaped such that the recess (51) connects the pressure sensor (50) and the intermediate space (22). Vacuum valve (10) according to one of claims 12 or 13, characterized in that a length of a flow path in the The gap (22) from the sleeve recess (21) to the recess (51) lies in a range of 20 to 40 times the width of the gap (22).

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