JP6431096B2 - Closure or airlock device for vacuum chamber - Google Patents

Description

  The present invention relates to a closure or airlock device for a vacuum chamber, which is a counter plate that can be placed in contact with the vacuum chamber and that surrounds the opening of the vacuum chamber, and is movable relative to the counter plate. The present invention relates to a closure or an airlock device provided with a closure lid that is attached, and in a closed position in contact with a counter plate, a closure lid that closes an opening of a vacuum chamber. The invention also relates to a method for closing the opening of a vacuum chamber using this type of closure or airlock device.

  Air locks and closure devices for vacuum chambers have long been known in the prior art. For example, Patent Document 1 describes this class of airlock device for an airlock opening disposed in a wall between a first receiving portion and a second receiving portion. And a blocking mechanism disposed in the inner space of the first receiving portion, and a counter plate assigned to the blocking mechanism. At this time, the counter plate that is formed in a flange shape and surrounds the opening is provided with a sealing portion that circulates, and the blocking mechanism is hermetically pressed.

  In order to maintain the required sealing, especially in order to maintain high vacuum conditions inside the vacuum chamber, the area of the sealing part in which this blocking mechanism is distributed as evenly as possible around the circumference of the opening It is worth pursuing to press. Applying an even and uniform pressing force on the seal over the entire seal is a seal with a seal diameter of a few millimeters and a blocking mechanism or closure lid size in the range of a few decimeters or meters Is particularly difficult from a construction and manufacturing engineering point of view.

Realizing a lift of about 0.5 mm to 2 mm compressing the sealing ring over the surface of the closure lid, for example in the range of 0.5 to ⁵ m ² or more, is possible in construction and production technology. It is clear that the cost is extremely high. Furthermore, the direct contact between the counter plate, typically made of metal, and the closure lid is due to the required clean room conditions and the associated particle-free conditions, which are required around the vacuum chamber. Should never be avoided.

  Shearing motion between the sealing part and the metal part abutting against it, typically between the sealing part and the closure lid, which can possibly occur when closing or closing the airlock device Should be avoided or reduced to a minimum, both because it also observes the required clean room conditions and because it should be particle free.

  In addition, seals typically made of an elastomeric material, such as rubber, can undergo aging and their elastic properties can change with continued use of the closure or airlock device. Furthermore, it is conceivable that the vacuum chamber is operated at different vacuum or pressure levels. As long as the closure or airlock device seals the inside of the vacuum chamber to the atmosphere or to other ambient pressures (eg, different from the adjacent vacuum chamber), the pressure on the seal Can vary depending on the pressure that prevails in the vacuum chamber, resulting in relative movement between the seal and the metal part of the closure or airlock device.

International Publication No. 2005/121621 A1 Pamphlet

  In this regard, it is an object of the present invention to provide an improved closure or airlock device for a vacuum chamber, and a method for closing a vacuum chamber associated therewith, with which a clearly defined It is possible to apply a particularly uniform pressing force to the sealing part, and this can be used to accurately set a predetermined distance or a required gap size between the counter plate on the housing side and the closing lid. is there. With this device, it is also possible to achieve a particularly high particle-free state in the region of the vacuum chamber. This closure or airlock device is further characterized by a relatively low weight and simple and good handling with regard to the manufacture and operation of its individual parts.

Invention and advantageous configurations This object is achieved by a closure or airlock device according to independent patent claim 1 and by a method for closing an opening of a vacuum chamber according to claim 12. Advantageous configurations are each the subject matter of the dependent patent claims.

  To this extent, a vacuum chamber closure or airlock device is provided. This closure or airlock device has a counter plate which can be placed in or is in contact with the vacuum chamber and, if necessary, integrated into the vacuum chamber or connected to the chamber wall, This counter plate surrounds the opening of the vacuum chamber. This counter plate is typically formed in a flange shape. The counter plate may or may have an abutment surface that projects outwardly from the wall of the vacuum chamber and extends in a direction substantially perpendicular to the insertion direction through the opening of the vacuum chamber.

  The closure or airlock device further includes a closure lid that is movably attached to the counter plate. The closing lid closes the opening of the vacuum chamber in a closed position in contact with the counter plate. The closure lid can be moved from a stationary or starting position, particularly at a distance from the counter plate, to a contact position with the counter plate and finally to a closed position, in which the closure lid is The plate is brought into contact with the plate and sealed to reach the contact, and the vacuum chamber opening is hermetically closed to that extent.

  In addition, the closure or airlock device has at least one closed loop and / or open loop controllable magnet device cooperating with the counter plate and the closure lid. This magnet device is formed to generate a closing force (S) acting between the counter plate and the closing lid. A closed loop controllable magnet device can be used to change the amount and direction of the closing force acting between the counter plate and the closing lid. Depending on the specific configuration of the magnet device, an attractive and repulsive force can be applied to the closure lid, thereby opening the vacuum chamber opening in response to the prevailing pressure level in the vacuum chamber and around the vacuum chamber. Can be optionally closed or opened using a closure lid.

  Furthermore, the closing or airlock device has at least one distance measuring device for measuring the distance between the closing lid and the counter plate. Using this distance measuring device, the distance between the closing lid and the counter plate can be measured at least in the form of a dot in the direction of the closing force coming out of the magnet device. The distance between the closing lid and the counter plate is based on the sealing portion provided between the counter plate and the closing lid, assuming that the closing lid is in contact with the counter plate above the closing portion. The magnitude of compression or elastic deformation that prevails at the present time. Therefore, the degree of elastic deformation of the sealed portion can be measured using this distance measuring device.

  For the closing or air-locking device, the magnet device is further provided so that it can be closed-loop controlled according to the distance between the counter plate and the closing lid as measured by the distance measuring device. In this way, by controlling the magnet device in a closed loop according to the distance, it is possible to generate different closing forces according to the distance, and as a result, for example, the sealing portion provided between the counter plate and the closing lid is , It can be compressed to the required size. With the aid of the distance measuring device and the return to at least one magnet device provided in this connection, very different states of the closing or airlock device can be detected.

  For example, by using a distance measuring device, it is possible to measure whether and how much the counter plate and the closing lid come into contact with each other in a sealed manner. If this distance exceeds, for example, the maximum value provided for a sufficient seal, a closed loop controllable magnet device is used to increase the closing force, e.g., below the maximum allowable maximum distance. It can be increased in steps.

  In the opposite case, if the distance between the counter plate and the closure lid is too small to be detected or measured, typically should be afraid of direct contact between the metal counter plate and the closure lid It can be further considered that. This point should be avoided, especially for the reason that a particle-free state is required in the periphery of the vacuum chamber. In such a case, the value of the closing force can be reduced, for example in steps, until a minimum allowable distance between the closing lid and the counter plate is exceeded.

  Therefore, it is possible to react to different or temporally variable pressure levels inside the vacuum chamber by closed-loop control and driving of the magnet device according to the distance. Due to the pressure difference between the inside and the surroundings of the vacuum chamber, or the pressure difference between this side and the other side of the closing lid, a closing force or an opening force can already be applied to the closing lid. Using a magnet device that can be controlled in a closed loop according to the distance, it is possible to compensate for the varying pressure difference on the opposing faces of the closure lid.

  According to an embodiment, the magnet device is arranged on at least one electromagnetic actuator disposed on one of the closing lid and the counter plate and on the other of the closing lid and the counter plate and is electromagnetic. And at least one counterpiece magnetically interacting with the actuator. The electromagnetic actuator can be arranged, for example, on the counter plate, or can be placed in the counter plate, while the counter piece can be arranged on the closing lid. In this case, it is further conceivable that the counterpiece is integrated in the closing lid or that the entire closing lid functions as a counterpiece.

  The counterpiece or closure lid is configured with ferromagnetism or as a permanent magnet for magnetically operative connection with an electromagnetic actuator to which a corresponding control current is applied. In the closed position of the closure lid in contact with the counter plate, the closure lid completely covers the opening cross section of the vacuum chamber, and the electromagnetic actuator and the counterpiece assigned to it overlap at least in certain areas, so that a sufficient closure is achieved. Force or opening force can be generated.

  In general, the electromagnetic actuator of the magnet device is arranged on the closing lid, while the counter piece that interacts magnetically with the electromagnetic actuator is arranged on or in contact with the counter plate Can be considered.

  Regardless of whether the electromagnetic actuator is located on the closing lid or on the counter plate, it is also possible to place at least one further permanent magnet on the part where the electromagnetic actuator is located, which The force derived from the actuator can be further supported. Thereby, for example, the closing lid can be closed without current, and as a result, a smaller current intensity can be applied to the coil of the actuator. Coil heat losses and the associated cooling or thermal expansion problems associated therewith can thereby be reduced or even eliminated.

  According to a further configuration, it further comprises at least one electronic closed loop control circuit, which is coupled to the distance measuring device and the at least one magnet device described above, between the counter plate and the closure lid. The predetermined distance is maintained and / or set. The closed loop control circuit typically includes a target value setting unit, and by using this, a distance signal that can be generated by the distance sensor can be compared with a predetermined target value. From the comparison between the target value and the current value, the controller connected behind the target value setting unit can generate a control signal for driving the magnet device, in particular for driving the electromagnetic actuator.

  The control signal that can be generated by the controller is typically supplied to the electromagnetic actuator of the magnet device via an amplifier. An electronic closed loop control circuit can be used to implement active and automatic closed loop control of the closing force. Thus, in response to sudden or continuous changes in operating or environmental conditions that may occur in some cases, for example, in response to changes in the pressure difference between the inside and the surroundings of the vacuum chamber, And it can react with flexibility depending on the condition. Using a closed loop control circuit that couples the distance measuring device and the magnet device to each other, the required distance between the counter plate and the closing lid, and hence the required pressing force of the closing lid, and the associated counter plate Compression of the seal provided between the closure lid is also caused and can be controlled and held.

  According to a further configuration, in the closed position of the closure lid, an elastically compressible sealing part surrounding the opening is arranged in contact with the closure lid or counter plate in the intermediate gap between the facing surfaces of the closure lid and the counter plate Has been. This sealing part can be arranged, for example, on the counter plate. For this purpose, the counter plate may have, for example, a notch that surrounds the opening of the vacuum chamber, in which a circulating sealing part is arranged. In the uncompressed initial state, the thickness or diameter of the sealing part is greater than the depth of the notch that receives the sealing part, so that a part of the sealing part is from the counterplate side on the closing lid side and therefore It protrudes at least slightly from the contact surface formed by the counter plate. With this configuration, the metal parts of the counter plate and the closing lid do not come into contact with each other, and the closing lid can come into contact with the sealing portion in a sealing manner.

  The facing surfaces of the closure lid and counter plate are typically configured as flat abutment surfaces, at least in certain areas, which in the closed position depend on the geometry of the vacuum chamber opening. It extends substantially perpendicular to the pre-given direction (z) or perpendicular to the closing direction in which the closing force derived from the magnet device acts.

  The sealing part is typically made of an elastomer and has an elasticity or compressibility suitable for a predetermined use. It is further conceivable to use sealing parts with different elastic or mechanical properties for different closing or use of the airlock device by controlling the closing force of the magnet device in a closed loop according to the distance. By controlling the closing force according to the distance in a closed loop, the closing or airlock device can be adapted to different or varying elastic properties of each sealing part provided.

  According to a further configuration, at the closing position of the closing lid, at least one plastic spacer is arranged on one of the mutually facing surfaces of the closing lid and the counter plate, the spacer being arranged on the counter plate. And prevent direct contact position with the closure lid. The elasticity or compressibility of the spacer is smaller than that of the sealed portion that can be disposed between the closing lid and the counter plate. The spacer can be arranged adjacent to the sealing part of the counter plate or in contact with the closing lid. The structural height of this spacer is normal to the abutment surface of the counter plate and / or closure lid, and the sealing part protrudes from the abutment surface of the associated closure lid or counter plate in the initial uncompressed state. It is smaller than the height of the minute.

  The spacer is implemented in some form of end stopper in order to avoid direct metal contact between the counter plate and the closure lid. In the control operation, at the same time, contact with the closing lid and the counter plate by the spacer should be avoided. However, the spacer also functions inter alia for the calibration of the distance measuring device. Thus, at a 1st process, a magnet apparatus can be driven so that a closure lid may contact this, without compressing a sealing part. This position indicates the maximum distance that can be set or closed-loop controlled. In the second step, the magnet device is driven so that the spacer contacts both the closing lid and the counter plate. This position corresponds to the minimum distance that can be set.

  The distance sensor of the distance measuring device can then be calibrated from the minimum and maximum distances. From both of these distances, a relative closed-loop control range or travel range can be derived. The assembly tolerances of the distance sensor that can possibly occur, for example in the counter plate, can be compensated or reduced accordingly. This type of calibration is particularly advantageous when a plurality of distance sensors are arranged on at least one of the closure lid and the counter plate.

  Typically, the spacer is disposed on the counter plate along with the seal. However, it is also conceivable that the spacer and the sealing portion are disposed on the counter plate side surface of the closing lid. It is also conceivable to arrange the sealing part and the spacer differently on the counter plate and the closing lid. For example, it is possible to arrange the sealing part on the counter plate while arranging the spacer on the closing lid. It is conceivable that the sealing portion is positioned on the side of the closing lid and the spacer is positioned on the counter plate side.

  The dimensions of the spacers are placed on the counter plate or closure lid, for example, only when the sealing part is almost maximally compressed or elastically compared with the sealing part and the geometry of the notch that houses the sealing part. The spacer is dimensioned so as to reach the abutment position with both parts, namely the counter plate and the closure lid. Direct metal contact between the counter plate and the closure lid can be avoided by using at least one spacer, preferably a plurality of spacers arranged around the opening and distributed.

  According to a further configuration, a plurality of magnet devices each having its own distance measuring device are distributed over the periphery of the opening or the counter plate configured in a flange shape, for example. ing. By providing a plurality of magnet arrangements distributed over the periphery of the opening, a particularly uniform pressing force and closing force can be set between the counter plate and the closing lid. This further allows control technology to compensate for possible deformations or inaccuracies in the production of the counter plate and / or the closure lid.

  Each distance measuring device combined with one magnet device sets the predetermined distance between the counter plate and the closing lid autonomously at the location of the corresponding distance measuring device or the location of the magnet device. And this can be maintained. The minimum deformation of the closure lid, which is unavoidable in response to pressure, can cause unequal pressing or closing force on the seal without it, but this minimum deformation is effectively compensated by the above. Can counteract the size of the unequal gap between the closure lid and the counter plate, or the distance between the closure lid and the counter plate that varies around the opening.

  Depending on the load that may occur in some cases or due to manufacturing variations, or component tolerances can be compensated for in the control technology. Multiple magnet devices, each with its own distance measuring device, can generate locally different closing forces and pressing forces around the perimeter of the opening or counter plate, so that The compression as uniform as possible of the sealing part can be controlled and set according to the purpose, and this compression ultimately provides the required sealing properties of the closure or airlock device. In practical applications, this configuration is particularly advantageous, i.e., especially when at least one of the closure lid and the counterplate is not formed with full rigidity and / or locally depending on the load This is advantageous when undergoing deformation.

  By using a plurality of magnet devices each provided with one distance measuring device, this kind of influence can be corrected and compensated in terms of control technology. Due to the structural form of the closure lid and / or counter plate, it can be accepted that the tolerances or mechanical deformations of the components are relatively large, so that the closure lid and counter plate are relatively large. Even in the case of an area configuration, it is possible to provide a comparatively light and gold structure, and thus a lightweight structural shape.

  According to a further configuration of the closure or airlock device, the magnet arrangement arranged around the opening of the vacuum chamber, or around the counter plate or around the closure lid, Each is provided to be coupled to its own closed loop control circuit. Each at least several magnet arrangements, preferably distributed in the circumferential direction, preferably around the opening or over the outer edge of the counterplate, each have a unique closed-loop control circuit. Thus, each magnet device does not depend on each other, and the distance or the size of the gap between the closing lid and the counter plate, which are dominant in their positions, can be set, and the closed loop control can be performed.

  As a result, the processing of the distance signal obtained from each distance measuring device can be performed locally in the area of the magnet device and the closed loop control circuit. As a result, data lines and signal lines that can possibly occur can be reduced to a minimum, which can be particularly advantageous in applications in the vacuum region.

  In a further configuration, the magnet devices and / or the distance measuring devices assigned to the magnet devices arranged in a distributed manner around the periphery of the opening are coupled to the central control. This central control can be provided in place of the local closed loop control circuit or to supplement the closed loop control circuit assigned to each magnet device and its associated distance sensor. The central control unit can, for example, be coupled in a data technology with a fully closed loop control circuit of an all magnet device, which can be used to drive the closed loop control circuit synchronously in a particularly simple manner.

  For example, each central control unit can be combined with a target value setting unit of each individual closed loop control circuit, so that using the central control unit, the distance to be maintained between the counter plate and the closing lid is fully closed loop. It can be transmitted to the control circuit at the same time. With the central control, the user of the closure or airlock device obtains an operating member that can be operated in a particularly simple manner, which is used to connect the closure lid and counter plate for the fully closed loop control circuit and the magnet device. The distance to be maintained between or the corresponding gap sizes can be set synchronously or simultaneously.

  Various distance measuring devices can be provided for each of the various configurations of the closure or airlock device. This distance measuring device can have, for example, one or more distance sensors, which are based on optical, magnetic or capacitive measuring principles. In particular, a sensor based on inductive measurement principle or eddy current is adopted. The distance sensor is arranged in particular in the immediate vicinity of the magnet device, in particular in the immediate vicinity of the electromagnetic actuator of the magnet device or in the immediate vicinity of the counterpiece, in order to obtain the highest possible collocation. Arranging the distance measuring device and the magnet device so as to be directly adjacent to each other or even overlap each other contributes to improvement of accuracy of measurement and closed loop control. The distance sensor can be arranged inter alia on the counter plate and can therefore measure the distance between the counter plate and the closure lid, in particular the size of the gap. A distance sensor located on the counter plate, in particular, to measure the distance to the defined reference surface or reference point of the closure lid accurately, typically with accuracy in the submillimeter to micrometer range. Is formed.

  Further redundancy is obtained by providing a plurality of magnet devices distributed around the closure lid or around the opening of the counter plate. If for any reason an individual magnet device does not always function correctly or fails, the remaining magnet device can take on the challenge, so that an uncontrolled opening or closing movement of the closing lid can be avoided. is there.

  According to a further configuration, the closure lid is slidably attached to a guide part extending parallel to the plane of the opening. This closing lid is slidably mounted, in particular, parallel to the contact surface of the counter plate. In this case, the guide part functions as a sliding guide part and is fixed in position, and can be arranged, for example, in the basic skeleton part or the base part of the vacuum chamber. Furthermore, it is conceivable that the guide part is connected to or arranged in the vacuum chamber in another way.

  The closure lid typically extends in a plane oriented in a direction perpendicular to the insertion direction of the opening. The counter plate, along with its abutment surface, typically extends parallel to the guide for the closure lid and parallel to the orientation of the closure lid. For the sliding guide part, in particular, the closing lid is in the rest position, i.e. provided at a predetermined distance from the counter plate in the insertion direction of the opening. In this way, the closing lid can be slid along the guide portion without colliding.

  The guide part has, for example, a guide rail, which extends above, below the opening of the vacuum chamber or to the side if necessary. With this sliding guide, the closure lid is moved from the rest position (this is the position where the closure lid substantially covers the opening of the vacuum chamber, but at a distance from it) In a position, the closure lid is located against the opening of the vacuum chamber without covering from above, so that the opening is accessible, for example, to feed or remove a substrate to be processed in the vacuum chamber. Yes).

  The sliding guide is suitable, inter alia, for constructing a closure or airlock device in a space-saving manner and for arranging this device in the area of a process station for processing substrates. Unlike in the case of a pivotingly mounted closure lid, the area outside the vacuum chamber opening and in the so-called extension of the opening is used to place further components of the process station and is closed Unlike the case of the pivotable shaft support of the lid, it is usually not necessary to keep it open.

  According to this further configuration, the closure lid is mounted without contact with the guide part using one or more magnetic bearings. The one or more magnetic bearings can be configured in particular as active closed-loop control magnetic bearings or passive magnetic bearings, but with this magnetic bearing, relative to and relative to the counterplate. It is possible to slide the closure lid without contact and therefore with little wear and low maintenance. Unlike the case of the guide part of the closing lid which is rolling bearing, the bearing of the closing lid based on the magnetic bearing does not wear at all. The required clean room conditions and the required particle-free conditions in the area of closures or airlock devices can thus be achieved without difficulty.

  The magnetic bearing provided for the guide is similar to the magnetic device provided for the closing or airlock device, respectively, an electromagnetic actuator, a counter piece that interacts magnetically with this, a distance measuring device, A closed-loop control circuit, so that the closure lid is free-floating and mounted with a predetermined distance to the guide part using one or more magnetic bearings, and the guide part It is movable along.

  For this purpose, various configurations and alternate arrangements of the counterpiece and the magnetic actuator are conceivable. A permanent magnet or a ferromagnetic counterpiece can be provided in a stationary manner in the guide 62 and an electromagnetic actuator in the closure lid 18. Alternatively, the actuator can be disposed on the guide lid 62 while the counterpiece is disposed on the movable closing lid 18.

  According to a further configuration of the guide part, the closure lid is attached to the guide part movably between a stationary position spaced from the counter plate and a closed position sealing the opening, using at least one retainer It has been. This retainer makes it possible in particular to move the closure lid perpendicular to the sliding direction previously provided by the guide part. With this cage, the closure lid can be moved from a rest position at a distance to the counter plate in the insertion direction (z) or in the closing direction, ie towards the counter plate, The closed position can be reached by sealing with the counter plate.

  Movement of the closure lid between a stationary position at a distance and a closed position that seals against the counter plate is performed using at least one, preferably a plurality of magnet devices, of a closure or airlock device. It can be broken. As such, no special drive is required for the movement of the closure lid between the rest position and the closure position. In this case, inter alia, a cage is provided to cause a parallel sliding of the closing lid in the direction of the surface normal of the closing lid in the rest position and thus to support this parallel sliding.

  In order to avoid possible shearing movements between the closure lid and the sealing part, the application of the closure lid and the counter plate, inter alia, around the closure lid and over the outer edge of the counter plate, It is clear that it is particularly advantageous when generating a closing force that acts as uniformly as possible in the direction perpendicular to the tangent surface.

  Finally, according to a further independent aspect, a method is provided for closing the vacuum chamber opening using any of the closures or airlock devices described above. The method includes the step of measuring the distance or size of the gap between the closure lid and the counter plate with at least one distance measuring device. Thereafter, the method includes driving at least one closed-loop controllable magnet device to generate a closing force that acts between the counter plate and the closing lid according to the measured distance. In this case, at least one distance is measured between the closing lid and the counter plate, and at least one closed loop controllable magnet device is connected between the counter plate and the closing lid according to the measured distance. In order to maintain the predetermined distance or the size of the gap, it is provided to be driven.

  Similarly, the method is provided to measure a plurality of distances between the closure lid and the counter plate, particularly at various portions of the closure lid and the counter plate, simultaneously or offset in time. Multiple distance measurements are preferably made using a corresponding number of distance measuring devices, which typically are located around the closure lid or around the counter plate. It is distributed. Each of these distance measuring devices is typically assigned its own magnet device, each of which is specifically a closed loop control circuit provided for this purpose (this is a distance measuring device for each magnet). Can be driven with a device).

  In this way, in different parts and different positions of the closure lid, in order to locally generate and maintain the required distance causing the required distance between the closure lid and the counter plate, respectively. The amount can be adjusted dynamically.

  It should be noted overall that the method described above can be implemented using, among other things, the closure or airlock device described above. To that extent, all features and advantages mentioned for the closure or airlock device apply equally well for the method and vice versa.

  According to a further configuration of the method, in order to calibrate the closed loop controllable magnet device and / or the associated distance measuring device, first the closing lid is first placed on the counter plate using the first drive of the magnet device. In a subsequent step, and subsequently the closure lid is typically compressed or deformed using the second drive of the magnet device while compressing or deforming the seal. It is provided to move to a contact position with a spacer arranged on the counter plate.

  In other words, using a first drive, i.e. by first applying a control signal, in particular a control current, to the associated electromagnetic actuator, or of a magnet arrangement that is distributed over the periphery. By actuating a plurality of electromagnetic actuators in synchronism, the closing lid is moved to a position where it comes into contact with the counter plate, where the closing lid is between the counter plate or counter plate and the closing lid without any pressing pressure. It abuts on the sealing part arranged in the.

  The distance signal associated with the first drive of the distance measuring device is useful for calibration of the distance sensor. This distance signal is considered to be the same as the zero state or the uncompressed state of the sealed portion. This represents the maximum distance for the closed loop control circuit.

  Conversely, the second drive is used to derive the maximum control signal that is acceptable for the magnet device, in which case the seal is maximally compressed and accordingly the closure lid is in contact with the spacer. Moved to position or contact position.

  The control signal to be prepared to cause this abutment position shows the maximum value, so that the magnet device can apply the maximum compression to the seal. Abutting or stopping the spacer and reaching the contact position can be read from the characteristic curves for the measurement distance and the driving of the magnet device. The maximum distance can be measured by reaching the contact position, and the minimum distance can be measured by reaching the contact position in contact with the spacer. Using the minimum and maximum distances, the associated distance sensor can be calibrated.

  With the first drive, a first maximum distance between the closure lid and the counter plate for a closed loop control of the distance can be measured. Conversely, when the second driving is used, the second minimum distance can be measured. Based on the minimum and maximum distances derived at this point, the distance measuring device can be calibrated for closed and open loop control of the magnet device. It becomes unnecessary to know the position of the distance sensor itself relative to one of the counter plate and the closing lid.

  Any intermediate value between the corresponding minimum control signal and maximum control signal can be set for each required sealing and depending on the pressure difference between the interior space of the chamber and the periphery of the chamber .

  Further objects, features and advantageous configurations of the present invention will be described in detail in the following description of embodiments with reference to the drawings.

FIG. 2 is a simplified schematic diagram of a closure or airlock device with a closure lid in an initial or stationary position. FIG. 2 is a view of the closure or airlock device of FIG. 1, comprising a closure lid, wherein the closure lid is in contact with the counter plate. FIG. 2 is a schematic view showing the closure or airlock device of FIG. 2 with a closure lid, which is in contact with a spacer disposed between the closure lid and the counter plate; is there. FIG. 4 is a view of the closure or airlock device of FIGS. 1 to 3, comprising a closure lid, wherein the closure lid is in a closed position where the closing force (S) is an intermediate value. It is a top view of the closure or airlock device provided with the notch which goes around on the counter plate side in order to accommodate a sealing part. FIG. 6 is a cross-sectional view taken along line AA in FIG. 5. A further configuration of a closure or airlock device, comprising a plurality of notches distributed around the periphery of the vacuum chamber opening, each containing a respective electromagnetic actuator of the magnet device FIG. 2 is a diagram provided for performing and arranging. It is sectional drawing along BB of FIG. It is a figure which shows the structure of the closure or air-lock apparatus provided with the some ring-shaped notch thru | or electromagnetic actuator arrange | positioned dispersively around the opening boundary part. FIG. 10 is a cross-sectional view taken along the line CC in FIG. 9. FIG. 6 is a schematic view of a closure lid that is slidably supported along a linear guide and is in a release position. FIG. 12 is a view similar to the presentation in FIG. 11, but with a closure lid that is in a resting or contacting position that contacts the counterplate of the closure or airlock device. FIG. 13 is a side view of the closure or airlock device of FIG. 12 with a closure lid that is in a rest position. FIG. 14 is a view similar to FIG. 13, but showing a closure lid, which is in a closed position and is attached to a position that sealingly contacts the counter plate. It is a further structure of a sliding guide part, Comprising: It is a figure which shows the place provided with the further magnet apparatus and this magnet apparatus is arrange | positioned at the edge part of the closing lid facing a guide part. 3 is a flowchart of a method for calibrating a closure or airlock device.

Detailed Description The closure or airlock device 10 shown in the cross-sectional view of FIG. 1 is provided for placement in an opening 14 of a vacuum chamber 12. The closure or airlock device 10 has a counter plate 16 which is typically connected to the wall 11 of the vacuum chamber 12 schematically suggested in FIG. The counter plate 16 can be disposed on the wall 11 in the same plane as the opening 14 of the vacuum chamber 12, or can be formed as an indispensable component of the vacuum chamber 12. In this respect, the counter plate 16 can also have an opening 14, which can typically coincide with the opening of the vacuum chamber 12.

  The closure or airlock device further comprises a closure lid 18 movably attached to the counter plate 16, which is open, for example in the closed position 28 illustrated in FIGS. 3 and 4. 14 is closed airtight or vacuum tightly. The counter plate 16 and the closing lid 18 further include at least one magnet device 30, and a closing force (S) can be applied to the closing lid 18 using this magnet device.

  The counter plate 16 can have a flange-like geometry and can have a sealing part 22, in particular a surface 17 that functions as an abutment surface on the side of the closure lid 18, this sealing part around the opening 14. Thus, typically, it extends in the region of the opening boundary portion of the counter plate 16. Here, the sealing portion 22 made of an elastic and deformable material is disposed in a notch 20 that goes around the counter plate 16. However, this seal can also be arranged in the corresponding notch of the closure lid 18 or in the intermediate gap 25 between the closure lid 18 and the counter plate 16. Upon reaching the closed position 28 illustrated in FIGS. 3 and 4, the seal 22 is deformed or crushed between the closure lid 18 and the counter plate 16 so that the opening 14 is hermetically closed. .

  Using the magnet device 30, a closing force (S) directed in the insertion direction or the closing direction (z) can be applied to the closing lid 18. This closing force (S) is typically oriented perpendicular to the plane (x, y) or perpendicular to the abutment surface or surface 17 of the counter plate 16. The closing lid 18 also has a surface 19 on the counter plate 16 side which also functions as a contact surface. In the closed position 28, the side surfaces 17, 19 of the counter plate 18 and the closure lid 19 are at least partially oriented parallel to each other.

  The associated abutment surfaces of the mutually corresponding surfaces 17, 19 extend here in the xy plane.

  The magnet device 30 in this case has at least one electromagnetic actuator 32 arranged on the counter plate 16 and a counterpiece 34 magnetically interacting therewith and arranged on the closure lid 18. The counterpiece 34 is configured as a permanent magnet or a ferromagnetic part, which is arranged in the closure lid 18 or embedded in the closure lid 18. Furthermore, it is also conceivable that the closure lid 18 itself has at least partly a permanent magnet material or a ferromagnetic material, or at least a region is formed entirely of such a material.

  By applying or applying a current to the coil 33 of the electromagnetic actuator 32, an attractive force or a repulsive force can be applied to the closing lid 18. By controlling the current intensity in a closed loop or by changing the control signal, the closing force (S) output from the magnet device 30 can be changed as needed.

  The closure or airlock device 10 further comprises a distance measuring device 40, which is used for the distance 41 between the closure lid 18 and the counter plate 16, in particular the surfaces of the closure lid 18 and the counter plate 16 on each side. The distance between 19 and 17 can be measured and can be measured quantitatively. The distance measuring device 40 in this case has a distance sensor 42 arranged on the counter plate 16, which measures the distance 41 in the closing direction (z) between the counter plate 16 and the closing lid 18. Accordingly, the distance measuring device 40 can be used to perform the closed loop control of the magnet device 30, particularly the closing force (z) generated therefrom, according to the distance. In particular, the distance 41 between the closing lid 18 and the counter plate 16 can be accurately set to a predetermined size by controlling the magnet device 30 in a closed loop according to the distance.

  For the closed loop control according to the distance, a closed loop control circuit 45 is provided, in particular, which couples the magnet device 30 with the distance measuring device 40. The closed loop control circuit 45 has a target value setting unit 44, which is connected to the distance sensor 42 in terms of data technology. The target value setting unit 44 receives the distance signals prepared from the distance sensor 42 and compares them with target values that are set in advance or that can be variably preset by the central control unit 50. The target value and the current value are compared with each other in the target value setting unit 44.

  The resulting comparison signal therefrom is then supplied to the controller 46, which generates a control signal provided for driving the electromagnetic actuator 32 from this comparison signal. The open loop control signal that can be generated by the controller 46 is supplied to the electromagnetic actuator 32 via the amplifier 48. If a predetermined distance 41 between the counter plate 16 and the closure lid 18 is maintained and different from the required distance, the force emanating from the magnet device 30 is dynamically adjusted to maintain this distance 41. Therefore, an amplified control signal that can be supplied to the coil 33 of the electromagnetic actuator 32 is calculated and determined.

  All the electronic components of the closed-loop control circuit, ie the amplifier 48, the controller 46, the target value setting unit 44 and, if necessary, the distance sensor 42 can also be accommodated on a common substrate, for example in the form of an integrated circuit. . The need for a corresponding electronic system location and the associated wiring costs can be minimized in this regard.

  The electromagnetic actuator 32 typically has a ferromagnetic core, for example, an iron core, other than the coil 30 to which an electrical signal is applied. The electromagnetic actuator 32 can be configured as an electromagnet, but can also be configured in a variety of other ways, such as a Lorentz actuator or a voice coil actuator. Unlike an electromagnet, a voice coil actuator can generate not only an attractive force but also a repulsive force between an electromagnetic actuator and a counterpiece.

  In principle, a different configuration of the magnet device 30 capable of closed-loop control according to the distance can be considered. In the configuration of the closure or airlock device 100 illustrated in FIGS. 5 and 6, the counter plate 16 has only one notch 31 which in this case surrounds the rectangular opening 14, in which the contour of the opening is drawn. At least one integral magnet coil with one or more openings 14 along the way can be disposed. In this case, in particular due to redundancy, a plurality of such integral magnet coils are arranged in one and the same notch 31, and each of these magnet coils has its own or the same distance measuring device 40 and a corresponding closed-loop control. Coupling through the circuit 45 is conceivable. Multiple coils can be used to achieve further improvements in closed loop controllability.

  In another embodiment of the closure or airlock device 10 presented in FIGS. 1-4, 7 and 8, a plurality of magnet devices 30 are arranged around the opening 14. Each of these magnet devices 30 has at least one electromagnetic actuator 32, which is arranged in the notch 31 of the counter plate 16. Each of these magnet devices 30 can be provided with a unique distance measuring device 40 as well as a unique local closed loop control circuit 45. In this way, the closed distance control of the individual distance between the counter plate and the closure lid can be performed over the contour of the opening, especially along the opening boundary, as appropriate and spatially resolved as required. As a result, it is possible to eliminate assembly tolerances or component tolerances and local deformations of the closure lid and / or counterplate that may occur in some cases.

  The notch 31 provided for accommodating the electromagnetic actuator 32 or its coil 33 is covered and / or sealed in the direction of the counterpiece 34 for reasons of vacuum stability. The covering portion 21 provided for this purpose is typically made of a magnetically permeable material, a nonmagnetic material, or a weak magnetic material. The covering portion 21 can function as a so-called closing portion for the notch 31 and can be formed as such. In this case, using a separate sealing part not explicitly shown, the covering part 21 can be placed above or in the notch 31 in a sealing manner. The covering part 21 can be integrated so as to be coplanar, in particular in the face 17 facing the counterpiece 34, and thus in the contact face of the counter plate 16 or the closure lid 18. For ease of viewing, the covering portion 21 is shown only on the right counter plate 16 in FIG.

  The magnet devices 30 that are distributed around the periphery of the opening 14 are each in the area of the opening 14 depending on the distance 41 between the counter plate 16 and the closure lid 18 that predominates in those regions. It can be closed-loop controlled so that the distance 41 can be kept constant or set within a small tolerance around the entire outer periphery.

  In the illustration of a further embodiment of the closure or airlock device 200 shown in FIGS. 9 and 10, a plurality of individual magnet devices are encased in the counter plate 16. The notches 31 provided for accommodating the individual electromagnetic actuators 32 in this case have a circular or ring geometry. With the aid of a plurality of magnet devices arranged in the circumferential direction of the opening 14 illustrated in FIG. 9, high spatial resolution and correspondingly accurate between the closure lid 18 and the counter plate 16 are achieved. Closed loop control of distance can be performed. The sealing part 22 is not explicitly shown in FIGS. 5 to 10 for the reason of easy illustration.

  As further illustrated in FIG. 1, there is at least one spacer 24 between the opposing surfaces 17, 19 of the counter plate 16 and the closure lid 18, which functions as an end stop for the closure lid 18. In a state where the sealing portion as shown in FIGS. 1 and 2 is not compressed, the sealing portion protrudes larger than the spacer 24 from the surface 17 that functions as a contact surface of the counter plate 16. As shown in FIG. 3, the spacer 24 contacts the closing lid 18 in the closed position 28 only when the sealing portion 22 is compressed or deformed to the maximum extent.

  The spacer 24 prevents, among other things, direct contact between the metal counter plate 16 and the metal closure lid 18. The spacer 24 is made of plastic, for example, polyether ether ketone (PEEK). 2 to 4 show an upper section of the closure or airlock device. In FIG. 2, the closing lid 18 is in a position 27 that is in contact with the circulating sealing portion 22 without any force. In this contact position 27, a closing force is applied to the closing lid 18 that only abuts the sealing portion 22 and does not substantially deform or compress it.

  In this case, this contact position 27 corresponds to a first drive of at least one magnet device 30. Corresponding control signals can be stored, for example, in the central control unit 50 or locally, for example in the controller 46 of the corresponding closed-loop control circuit 45, in particular stored for calibrating the distance measuring device. Can be done. For calibration purposes, the magnet device 30 can be subjected to a control signal, typically a current, so that a minimum distance 41 is set between the closure lid 18 and the counter plate 16.

  This minimum distance is achieved when the closure lid 18 reaches a contact position with the spacer 24 as shown in FIG. 3 or when the spacer 24 contacts both the closure lid 18 and the counter plate 16. . The closure lid 18 is moved on the stopper, so to speak, or with the spacer 24 and thus with the counter plate 16 to the stop position. In order to achieve the maximum closed position 28, the magnet device 30 can be acted upon by a second or maximum control signal. This maximum control signal can be stored individually and locally in the central controller 50 or in the controller 46 of the fully closed loop control circuit 45, as well as functioning for calibration of the distance measuring device. To do. In this way, it is possible to derive the minimum distance 41 between the counter plate 16 and the closing lid 18 that can be closed-loop controlled for each distance measuring device.

  In FIG. 16, the calibration method illustrated in FIGS. 2 to 4 is again shown in block diagram form. In the first step 300, the closure lid 18 is transferred to the contact position 27 shown in FIG. The control signal required for this and for the at least one magnet device or the corresponding first maximum closed-loop controllable distance 41 is then stored in step 302. The associated control signal or the maximum or first distance 41 can be derived very easily from the characteristic curve of the measuring distance 41 for the control signal applied to the magnet device.

  Thereafter, in step 304, the second drive of at least one magnet device 30 is realized as shown in FIG. The maximum control signal accompanying this can also be read from the above-mentioned characteristic curve. This control signal corresponds to a current intensity after which the further increase in current intensity no longer leads to a measurable decrease in distance 41. This is an index indicating that the stop position has been achieved using the spacer 24. Step 306 then derives a second minimum distance between the closure lid and the counter plate. Based on the measured minimum and maximum distance at which the seal 22 can come into contact with both the closure lid and the counter plate, the distance measuring device 40 and thus the magnet device 30 capable of closed loop control and open loop control can be calibrated. is there.

  11 and 12, a front view of the closure or airlock device is shown. At this time, the closing lid 18 is slidably attached to a guide portion 62 extending in the vertical direction. This guide part 62 is configured as a sliding guide part and extends parallel to the plane of the abutment surface (x, y) formed by the counter plate 16 and / or the closure lid 18 and therefore The counter plate 16 and the closing lid 18 extend parallel to the mutually facing surfaces 17 and 19. However, as is apparent from the side view of FIG. 13, the guide part 62 is arranged at a distance from the counter plate 16 in the closing direction (z), so that, in particular, the closing lid 18 is placed on the counter plate 16. Can be slid without colliding.

  As suggested in FIG. 11, the closure lid 18 is attached to the guide part 62 without contact, especially via at least one, typically two or more, magnetic bearings 60 spaced from each other. It has been. The individual magnetic bearings 60 are similar to the magnet device 30 and each has one distance sensor, a closed loop control circuit, and an electromagnetic that can be closed loop controlled via the distance sensor and the closed loop control circuit, which are not individually shown here. This electromagnetic actuator cooperates with the counterpiece 63 magnetically. In this manner, the floating state of the closing lid 18 required in the guide portion 62 can be achieved. The non-contact attachment of the closing lid 18 at the guide portion 62 is particularly advantageous in order to avoid contamination and wear in the periphery of the vacuum chamber 12.

  In this case, a plurality of electromagnetic actuators 62 are provided along the guide portion 62, and these are sequentially engaged with the counterpiece 63 arranged on the carriage-like carrier 66 when the carrier 66 slides. In this case, the reverse arrangement is likewise within the framework of the invention. For example, one or more actuators 62 are arranged on the carrier 66 or the closure lid 18, while a counterpiece 63 that interacts magnetically therewith is arranged in a linear guide part 62 configured as a guide rail in a fixed position. Has been placed.

  In FIG. 11, the closure lid 18 is shown in the release position, in which the closure lid is outside the area of the counter plate 16. In FIG. 12, the closing lid 18 overlaps with the counter plate 16, so that the opening 14 can be hermetically closed.

  Comparing FIG. 13 and FIG. 14, the closure lid 18 is further slidable or movable in the closing direction (z), that is, perpendicular to the plane (x, y) of the closure lid 18 by using the cage 64 Thus, it is clear that the guide portion 62 is attached. With at least one magnet device 30 arranged along the circumference of the opening 14, the closure lid 18 is moved from the non-contact stationary position 26 shown in FIG. 13 to the contact position shown in FIG. 27 and further to the closed position 28. It is further conceivable to provide a separate drive for moving the closure lid 18 between the rest position 26 and the contact position 27, ie in a direction perpendicular to the plane of the closure lid 18.

  At this time, the retainer 64 slides the closing lid 18 in parallel from the stationary position 26 at a distance to the contact position 27 and further to the closing position 28, or assists this sliding, as a result. The relative movement of the closing lid 18 and the sealing portion 22 on the closing lid surface (X, Y) does not occur as much as possible. This type of shearing motion can lead to wear of the seal 22, if any, and at least slight contamination around the vacuum chamber 12.

  FIG. 15 is a perspective view of the closing or airlock device seen from an oblique direction. At the foot of the closure lid 18, a further guide part 70 is provided, which, like the guide part 62 attached with magnetism, is attached with magnetism and is configured in a non-contact manner. sell. The lower guide part 70 is not only able to slide in this case in a direction parallel to the surface of the closure lid, in this case in the horizontal direction. This guide part can contribute to sliding the closing lid 18 in parallel from its rest position 26 to the contact position 27 and further to the closing position 28 without any particular bending.

  The guide unit 70 70 can also be coupled to the unique distance measuring device 40. However, the distances of the total distance measuring devices 40 distributed over the periphery of the opening 14 are read via the central control unit 50 and used as a result. It is also conceivable that the orientation of the closure lid 18 in the yz plane can be inferred.

  The closing lid 18 is attached by the guide portion 62 in a non-contact manner, for example, by using a carrier 66 configured in a carriage shape connected to the closing lid. One of the components of the related magnetic bearing 60, that is, one of the electromagnetic actuator 61 and the counter piece 63 is disposed stationary on the guide portion 62, while the actuator 61 and the counter piece 63 The other part is disposed on the carrier 66. However, it is also conceivable that the electromagnetic actuator and the counterpiece are positioned and arranged differently. In order to slide the closing lid 18 or the carrier 66 along the guide part 62, a linear motor 68 is provided, by which the closing lid 18 is movable between the release position and the rest position 26. .

DESCRIPTION OF SYMBOLS 10 Closing or airlock apparatus 11 Wall part 12 Vacuum chamber 14 Opening 16 Counter plate 17 surface 18 Closing lid 19 surface 20 Notch 21 Covering part 22 Sealing part 24 Spacer 25 Intermediate gap 26 Rest position 27 Contact position 28 Closed position 30 Magnet apparatus 31 Notch 32 Electromagnetic actuator 33 Coil 34 Counterpiece 40 Distance measuring device 41 Distance 42 Distance sensor 44 Target value setting unit 45 Closed loop control circuit 46 Controller 48 Amplifier 50 Control unit 60 Magnetic bearing 61 Electromagnetic actuator 62 Guide unit 63 Counterpiece 64 Cage 66 Carrier 68 Linear motor 70 Guide part 100 Closing or airlock device 200 Closing or airlock device

Claims (13)

A closure or airlock device for a vacuum chamber (12),
A counter plate (16) that can be placed in contact with the vacuum chamber (12) and surrounds the opening (14) of the vacuum chamber (12);
A closing lid (18) movably attached to the counter plate (16), which closes the opening (14) in a closed position (28) in contact with the counter plate (16); A lid,
Engage with the counter plate (16) and the closure lid (18) to be able to control the closed loop and generate a closing force (S) acting between the counter plate (16) and the closure lid (18) At least one magnet device (30);
Comprising at least one distance measuring device (40) for measuring the distance (41) between the closure lid (18) and the counter plate (16);
The magnet device (30) is closed or loop-controllable according to the distance (41) between the counter plate (16) and the closure lid (18) measured by the distance measuring device (40). Air lock device.   The magnet device (30) includes at least one electromagnetic actuator (32) disposed on one of a closing lid (18) and a counter plate (16), a closing lid (18), and a counter plate (16). 2. The closure or airlock device according to claim 1, comprising at least one counterpiece (34) arranged on the other of the two and magnetically interacting with the electromagnetic actuator (32).   The electronic closed loop control circuit (45) is further coupled to the distance measuring device (40) and the magnet device (30), and includes a counter plate (16) and a closing lid (18). 3. The closure or airlock device according to claim 1, wherein the device is configured to maintain and / or set a predetermined distance between the first and the second.   In the closed position (28) of the closure lid (18), in the intermediate gap (25) between the mutually facing surfaces (17, 19) of the closure lid (18) and the counter plate (16), the closure lid (18) Or an elastically compressible seal (20) surrounding the opening (14) in contact with the counter plate (16), or a closure or air according to any one of claims 1 to 3 Locking device.   In the closed position (28) of the closure lid (18), at least one spacer (24) is provided on one of the mutually facing surfaces (17, 19) of the closure lid (18) and the counter plate (16). 5. The closure or airlock device according to claim 1, wherein the spacer prevents a direct contact position between the counter plate (16) and the closure lid (18).   A plurality of magnet devices (30) each having its own distance measuring device (40) are distributed and arranged around the opening (14). A closure or airlock device as described in.   7. A closure or airlock device according to claim 6, wherein the magnet devices (30) distributed around the opening (14) are each coupled to a unique closed loop control circuit (45). .   The magnet device (30) and / or the distance measuring device (40) assigned to the magnet device (30) arranged in a distributed manner around the opening (14) is connected to a central control unit (50). 8) The closure or airlock device according to claim 6 or 7.   The closure according to any one of the preceding claims, wherein the closure lid (18) is slidably attached to a guide part (62) extending parallel to the plane of the opening (14). Or air lock device.   10. A closure or airlock device according to claim 9, wherein the closure lid (18) is mounted without contact with the guide part (62) using one or more magnetic bearings (60).   The closure lid (18) has a stationary position (26) spaced from the counter plate using at least one retainer (64) and a closed position (28) sealing the opening (14). 11. The closure or airlock device according to claim 9 or 10, wherein the closure or airlock device is attached to the guide portion (62) so as to be movable between the two. A method for closing an opening (14) of a vacuum chamber (12) using the closure or airlock device (10; 100; 200) according to any one of the preceding claims, comprising the following steps:
Measuring at least one distance (41) between the closure lid (18) and the counter plate (16) with at least one distance measuring device (40);
At least one closed-loop controllable magnet device for generating a closing force (S) acting between the counter plate (16) and the closing lid (18) in response to the measured distance (41) And (30) driving the method. In order to calibrate the closed loop controllable magnet device (30) or the distance measuring device (40) associated therewith,
The first step of moving the closing lid (18) to the contact position with the sealing part (22) disposed on the counter plate (16) using the first drive of the magnet device (30); ,
Subsequently, the closing lid (18) and the counter plate (16) are moved under the compression of the sealing part (20) using the second drive of the magnet device (30), and the spacer (24 And the step of moving to a contact position with the method.

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