Vacuum adjustment device having a collet coupling

Abstract

A vacuum adjustment device having a coupling for coupling an active element and a drive unit is disclosed. The drive unit adjusts the coupling from a normal position into an active position, in which the active element provides its intended effect. A separating device separates the process atmosphere region (P) from an outer atmosphere region (A), wherein the drive unit is at least partially associated with the outer atmosphere region (A). The coupling has a locking element cooperating with a collet which are arranged for a relative position variation axially along or parallel to a receiving axis that the locking element is adjustable relative to the collet into an open position and into a closed position. The coupling provides an open changing state in the open position by the interaction of the collet with the locking element and a closed working state in the closed position.

Claims

1. A vacuum adjustment device for an active element movable in a process atmosphere area (P), in particular vacuum region, comprising a coupling designed for coupling the active element, a drive unit designed in such a way and cooperating with the coupling such that the coupling is adjustable back and forth from a normal position, in which the active element is present in the coupled state in a substantially effect-free state with respect to its intended effect, into an active position, in which the active element provides its intended effect, and a separating device for separating the process atmosphere region (P) from an outer atmosphere region (A), wherein the drive unit is assigned at least partially to the outer atmosphere region (A) and the coupling is assigned in particular to the process atmosphere region (P), the coupling has a collet and a locking element cooperating with the collet, wherein the coupling defines a receiving axis (Z) for receiving the active element, the collet and the locking element are arranged axially or parallel to the receiving axis (Z) to such a relative positional variation that the locking element is adjustable, in particular displaceable, to an open position and to a closed position relative to the collet, and the coupling provides an open changing state in the open position by the interaction of the collet with the locking element and a closed working state with the locking element in the closed position, wherein the vacuum adjustment device is formed and configured such that a change between the open position and the closed position for the locking element is adjusted by an axial adjustment of the coupling by the drive unit using an existing axial movement limit for the collet or the locking element.

2. The vacuum adjustment device according to claim 1, wherein at least one stop element is provided, wherein the at least one stop element is arranged and formed for interacting with the locking element or the collet.

3. The vacuum adjustment device according to claim 2, wherein in that the stop element is arranged on a housing of the vacuum adjustment device, on a process chamber cooperating with the vacuum adjustment device, or on the active element, or is formed by the housing, the process chamber or the active element.

4. The vacuum adjustment device according to claim 2, wherein the drive unit is formed such that the locking element is displaceable into the open position and/or closed position by means of cooperation with the at least one stop element by a movement of the coupling produced by the drive unit.

5. The vacuum adjustment device according to claim 2, wherein the drive unit is designed for a linear axial movement of the coupling along or parallel to the receiving axis (Z) for a specific total movement range, and the at least one stop element is arranged in the total movement range for adjusting the locking element as part of a movement of the coupling.

6. The vacuum adjustment device according to claim 5, wherein the total movement range is limited by a first and a second end position for the coupling, in particular for the collet, the open changing state is present in the first end position and the closed working state is present in the second end position, in particular wherein the open changing state can be provided by an adjustment of the coupling and the collet into the first end position, and the closed working state can be provided by an adjustment of the coupling and the collet into the second end position.

7. The vacuum adjustment device according to claim 5, wherein for the total movement range, a first and a second action zone are defined, wherein the first end position limits the first action zone and the locking element is adjustable in the first action zone such that the collet is present substantially radially free of force, and the second end position limits the second action zone and the locking element is adjustable in the second action zone such that the collet is acted on by a radial force.

8. The vacuum adjustment device according to claim 7, wherein the normal position and the active position of the coupling are provided with respect to the total movement range at least partially within the first and/or the second action zone.

9. The vacuum adjustment device according to claim 1, wherein the collet has a cylindrical or conical inner collet receptacle which defines the receiving axis (Z), the collet is designed as a radially slotted sleeve with a varying outer diameter along the receiving axis (Z), an inner diameter of the locking element is smaller than a maximum outer diameter of the collet, and the collet and the locking element are arranged such that the outer diameter of the collet cooperates with the inner diameter of the locking element and a force can be generated on the collet which is radially directed into the interior of the collet by means of adjusting the locking element along the receiving axis (Z).

10. The vacuum adjustment device according to claim 1, wherein the separating device is formed by a housing or bellows of the drive unit, and/or the drive unit is designed as a pneumatic drive cylinder.

11. The vacuum adjustment device according to claim 1, wherein the active element is formed as a support pin or as a valve closure.

12. The vacuum adjustment device according to claim 1, wherein the vacuum adjustment device comprises a control unit for controlling the drive unit, wherein the control unit has a maintenance functionality configured in such a way that in its execution, the axial position of the coupling is variable to provide the open changing state or the closed working state.

13. The vacuum adjustment device according to claim 1, wherein the vacuum adjustment device is formed as a pin lifting device, in particular a pin lifter, for the movement and positioning of a substrate to be processed, in particular a wafer, in a process atmosphere region (P) provided by a vacuum processing chamber and comprises the coupling as a first coupling, in particular out of a plurality of couplings, wherein the drive unit provides the at least linear mobility of the first coupling, the active position is formed by an equipping position for equipping the pin lifting device with the substrate, and the coupling is designed to receive a support pin designed to contact and support the substrate and form the active element.

14. The vacuum adjustment device according to claim 1, wherein the vacuum adjustment device is formed as a vacuum valve, in particular vacuum slide valve, pendulum valve or mono valve, for regulating a volume or mass flow and/or for the gas-tight interruption of a flow path, having a valve seat having a valve opening defining an opening axis (H) and a first sealing surface surrounding the valve opening, a valve closure forming the active element, in particular valve plate, for regulating the volume or mass flow and/or for interrupting the flow path, having a second sealing surface corresponding to the first sealing surface, the valve closure is coupled to the drive unit by means of the coupling such that the valve closure is adjustable from an open position as a normal position, in which the valve closure and the valve seat of the vacuum valve are present relative to each other without contact, into a closed position as the active position, in which a sealing contact between the first sealing surface and the second sealing surface is provided via an interposed seal and the valve opening is thus sealed in a gas-tight manner, and back again, and the coupling is designed to receive the valve closure.

Description

(1) The devices according to the invention are described below purely by way of example with reference to concrete embodiments shown schematically in the drawings, which also address further advantages of the invention, wherein the drawings show in detail:

(2) FIGS. 1a-c show an embodiment of a vacuum adjustment device according to the invention designed as a pin lifting device in different positions;

(3) FIGS. 2a-c show an embodiment of a collet coupling of an adjustment device according to the invention in different states; and

(4) FIGS. 3a-b show a further embodiment of a vacuum adjustment device according to the invention designed as a vacuum valve.

(5) FIGS. 1a to 1c show schematically an embodiment of a vacuum adjustment device 10 formed as pin lifting device in different positions.

(6) FIG. 1a shows the pin lifting device 10 in an operating or production state with a supporting pin 15 connected to a drive unit 12 by means of a coupling 11. The supporting pin 15 projects through a chamber wall 16 of a process chamber into the chamber interior. The drive unit 15 provides a linear axial (here: vertical) movement of the support pin 15 within the limits of a defined range of movement. This range of movement is limited here in particular by the arrangement of drive unit 15 relative to the process chamber.

(7) In particular, the drive unit is controlled in such a way that the support pin 15 is set into a receiving position for equipping the process chamber, i.e. it projects far into the process chamber. A substrate, e.g. a wafer, can be introduced by means of a robot arm through a vacuum transfer valve into a vacuum chamber. There, the robot arm allows a depositing of the wafer on the extended and further support pins (not shown here) of the pin lifting device 10. After placing the wafer on the pins, the robot arm is guided out of the chamber, the transfer valve is closed and the pins 15 are lowered by means of appropriate control. This is done by means of a drive or lifting cylinder of the drive unit 12 which is coupled to the pin 15 and thus provides a movement of the pin 15. The wafer can thus be deposited on intended support elements.

(8) In this state, a planned processing (e.g. coating) of the wafer under vacuum conditions and in particular in a defined atmosphere (i.e. with a certain process gas) then typically takes place. The chamber is coupled for this purpose to a vacuum pump and preferably to a vacuum control valve for controlling the chamber pressure (not shown).

(9) After processing, the wafer is raised again to a removal position by means of the pin lifting device 10. With a second robot arm, the wafer is subsequently removed through a second transfer valve. Alternatively, the process may be designed with only one robot arm, wherein placement and removal is then carried out by a single transfer valve.

(10) The support pin 15 is made in particular from an electrically non-conductive, e.g. ceramic, material and is cylindrical. The support pin 15 may alternatively be conductive, e.g. made of metal.

(11) The support pin is further clamped in the coupling 11 and can be used in this clamped state for carrying out the loading and unloading of the process chamber.

(12) As described above, over the duration of multiple part production due to wear or tear on the support pin 15, at least one replacement of the pin 15 will typically be required. The solution shown here allows easy and speedy maintenance of the pin 11 and optionally the device 10. For this purpose, the coupling 11 is provided between the support pin 15 and drive 12 and designed specifically.

(13) The coupling 11 has an inner collet and an outer locking element (e.g. a coupling ring), which cooperates with the collet. The locking element is adjustable relative to the collet axially along a receiving axis into an open position and a closed position, in particular displaceable in relation thereto. The receiving axis is formed by the displacement of the coupling 11 and the inner collect receptacle which is cylindrical or conical for example and is formed by the collet. In FIG. 1a, the coupling 11 is shown in a closed, clamped state, wherein the support pin 15 is locked by the tensioned collet in the coupling 11. The locking can be produced and released again by a corresponding axial adjustment of the locking element.

(14) The coupling can accordingly be displaced by the interaction of the collet with the locking element in an open changing state (open position of the locking element) and in a closed working state (closed position of the locking element).

(15) An actuation of the locking element and thus a change in the coupling state can be carried out by a targeted control of the drive unit.

(16) A part of the vacuum adjustment device 10 is located in a process atmosphere region P (vacuum area). This region P is not limited solely to the internal volume of the process chamber, but also expands through the passage for the support pin 15 to an area below the chamber. Also, the coupling 11 is thus disposed in the process atmosphere P. As already stated above, increased demands are placed within the process atmosphere P on process integrity, process reliability and cleanliness. Prevention of particles is considered a priority criterion. By means of the collet coupling 11, this requirement can be met. Due to the comparatively low effort and the correspondingly reduced sources of particle generation for replacing a support pinthere are, for example, no screw connections to be released and actuation can be done by the drive unit, a significant improvement in a typical adjustment assembly can be achieved with the use of a collet coupling 11.

(17) The coupling 11 may alternatively (not shown) be present in the outside atmosphere region A, wherein an atmospheric separation, e.g. by means of the chamber wall (e.g. sealed pin feedthrough), is provided.

(18) FIG. 1b shows the vacuum adjustment device 10, wherein the coupling 11 is moved by means of the drive unit 12 to a stop 13 (in the direction of the arrow). The stop 13 provides an actuation of the coupling 11, in particular of the locking element. The drawing shows the already established locking of the pin 15 after the relative movement of the locking element. The support pin 15 is thus in a blocked position in the coupling 11 and can be used in this state to perform a machining process.

(19) FIG. 1c shows the coupling 11 in the opened state and a pin 15 which is released from the coupling 11 or is to be inserted into the coupling 11. To open the coupling 11, it is brought into contact with a lower stop 14. The axial mobility of the locking element of the coupling 11 is limited on one side by this stop 14. The locking element is moved in a first step in contact with the stop 14 and in a subsequent step, the inner collet is further offset in the same axial direction. In other words, the collet is at least partially pulled out of the locking element. As a result, a radially inwardly directed force is reduced or dissolved on the collet and thus the force required to lock the pin 15.

(20) The reverse occurs for closing the coupling 11. The locking element is moved to the stop 13, in particular only for the purpose of making contact (in an essentially force-free manner), and the collet is then pushed by a continued axial movement into the element, whereby the collet is braced, i.e. the radially acting force is generated or increased on the collet. The support pin 15 is inserted before the insertion of the collet into the coupling 11.

(21) FIGS. 2a to 2c show an embodiment of a collet coupling 20 of an adjustment device according to the invention in different states.

(22) With FIG. 2a, the coupling 20 is shown in an open changing state without an assembly with an active element (e.g. valve plate or support pin). Reference numeral 26 designates a part of a cylindrical coupling section of an active element, i.e. the part of the element which is to be received in the coupling 20 and locked therein for its further use.

(23) The locking element, here designed as a coupling ring 21, has different inner radii or inside diameters with respect to the axial extension thereof. In a first end region 22, the inner radius is smaller compared to a central region 23.

(24) The collet 24 is adapted to the dimensions of the locking element 21 with respect to its spatial extension. The collet 24 has in an upper sleeve section a plurality of bracing or clamping legs 25, which are arranged here annularly. In particular, the collet 24 is formed as a slotted sleeve. The outer diameter of the collet in the region of the clamping legs 25 corresponds (without the presence of a force on the collet) substantially to the inner diameter of the coupling ring 21 in the central region 23 or is designed slightly larger to provide a defined pretension.

(25) The clamping legs 25 each have ends angled towards a central axis, where they produce a smaller internal diameter. This reduced (force-free) inner diameter substantially corresponds here to the diameter of the collet 24 in the lower region, below the clamping elements 25.

(26) The inner diameter of the coupling 20 in the open changing state, i.e. in particular the smallest inner diameter of the collet 24, and the (outer) diameter of the cylindrical coupling section 26 are applied with a corresponding spatial extension. The coupling section 26 can thus be introduced into the coupling 20 without considerable effort. It is understood that the collet 24 may have a slightly smaller inner diameter in order to provide a certain pretensioning and accurate alignability of the received coupling section 26.

(27) According to the invention, such a coupling design can be part of a vacuum adjustment device. A control 50 of the drive unit, which provides at least axially mobility of the coupling 20, is preferably configured such that a movement of the collet 24 in a stop of the locking element 21 can take place such that the axial region of the clamping elements 25 is adjustable only within the limits of the end region 22 and the central region 23. This can ensure that the collet 24 is not pulled out of the coupling ring 21.

(28) FIG. 2b also shows the coupling 20 in the open position. The coupling section 26 of the active element is inserted into the coupling 20 and pushed therein into the collet 24, but not locked. The coupling section 26 can thus be rotated, for example, about its axis of extension. The collet 24 has in particular at the lower end an inner boundary, e.g. an edge or stop, so that the coupling section 26 can be inserted into the collet 24 with a certain depth. This allows achieving a very precise reproducibility for the position of the active element.

(29) FIG. 2c shows the coupling 20 in a closed working state. The locking element 21 is offset for this purpose relative to the collet 24 in a closed position. The end region 22 of the locking element 21 in this case corresponds axially with respect to its position at least partially with the clamping legs 25, in particular with the region of the clamping legs 25 having an enlarged outer radius. This interaction results in a clamping force on the clamping legs 25 directed in the direction of the inner collet receptacle.

(30) The clamping force creates a bracing or clamping of the clamping legs 25 to the coupling section 26 such that the coupling section 26 is locked, i.e. it can withstand a comparatively large tensile force applied to the coupling section 26.

(31) In order to reach the closed position (FIG. 2b after FIG. 2c), the locking element 21 is in particular moved to an upper position stop and the collet 24 together with the inserted coupling section 26 is then pressed into the locking element 21.

(32) In order to reach the open position (FIG. 2c after FIG. 2a), the locking element 21 is moved in particular to a lower position stop and the collet 24 together with the inserted coupling section 26 is then pulled out of the locking element 21 over a defined distance.

(33) FIGS. 3a and 3b show schematically another embodiment of a vacuum adjustment device according to the invention, which is designed as a vacuum valve 30. In the example, the valve 30 is designed as a so-called mono valve and shown in cross-section in a valve-open position (FIG. 1a) and a valve-closed position (FIG. 1b).

(34) The valve 30 for gas-tight closing of a flow path by means of a linear movement has a valve housing 31 with an opening 32 for the flow path, wherein the opening 32 has a geometric opening axis H along the flow path. The opening 32 connects a first gas region L, which in the drawing is to the left of the valve 30 or a separating wall (not shown), with a second gas region R to the right thereof. Such a separating wall is formed, for example, by a chamber wall of a vacuum chamber.

(35) The closure element 34 (valve plate) forms the active element and is linearly displaceable along a geometric adjustment axis V, which extends transversely to the opening axis H, in a closure element plane from an open position releasing the opening 32 into a closed position which is linearly pushed in a closing direction over the opening 32 (FIG. 3b) and vice versa back in an opening direction by means of a drive unit 37 with a movable adjusting element 35, in the example a valve rod.

(36) For example, a (curved) first sealing surface 33 encloses the opening 32 of the valve housing 31 along a first section in a first plane 33a and along a second section in a second plane 33b. The first plane and the second plane are spaced apart, extend parallel to each other and parallel to the closure element plane. Thus, the first section 33a and the opposite second section 33b thus have a geometric offset to each other transversely to the adjustment axis V and in the direction of the opening axis H. The opening 32 is arranged between the two opposite sections 33a and 33b in the region extending along the adjustment axis V.

(37) The closure element 34 has a second sealing surface 36 corresponding to the first sealing surface 33, which extends along sections corresponding to the first and second sections 33a, 33b.

(38) In the example shown, a sealing material forming a seal is provided on the first sealing surface 33 of the valve seat. Alternatively or additionally, the seal may be arranged on the second sealing surface 36 of the valve closure.

(39) The seal may, for example, be vulcanized onto the valve seat as a polymer by means of vulcanization. Alternatively, the seal can be designed, for example, as an O-ring in a groove of the valve seat.

(40) Also, a sealing material may be adhered to the valve seat and thereby embody the seal. Such seals are of course not limited to the valve 30 described in the example, but are also applicable to the other described valve embodiments.

(41) Mono valves, i.e. vacuum valves closable by a single linear movement, have the advantage for example of a relatively simple closing mechanism, e.g. compared to transfer valves which are closable by means of two movements, which require a drive with a relatively complex structure. Since the closure element can also be formed in one piece, it can be exposed to high acceleration forces, so that this valve can also be used for rapid and emergency closures. The closing and sealing can be done by means of a single linear movement, so that a very fast closing and opening of the valve 1 is possible.

(42) In particular, it is an advantage of mono valves, for example, that the seal is not subject to any transverse load in the transverse direction to the longitudinal extension of the seal due to their progression during closing. On the other hand, due to its transverse extension relative to the opening axis H, the seal is hardly able to absorb forces acting on the closure element 34 along the opening axis H, which can act on the closure element 34, in particular with a large differential pressure, which requires a robust construction of the closure element 34, its drive and its storage.

(43) The vacuum valve 30 shown in FIGS. 3a and 3b comprises according to the invention a coupling 40 with a collet 44 and a clamping element 41 (locking element) axially movable relative to the collet 44. The clamping element 41 is capable of displacing the coupling 40 into an open changing state and a closed working state by varying the axial relative position (relative to the collet). In FIG. 3a, the open changing state is shown.

(44) The coupling 40 is designed in this case so that the clamping element 41 is coupled to the valve rod 35 and can be guided. The collet 44 is moved passively, i.e. the collet 44 is movable relative to the clamping element 41 in that the collet 44 abuts on a stop and the clamping element 41 is moved further, beyond the contact point. For this purpose, an inner stop 46 is provided, which is formed, for example, in the rod 35 designed as a tube. Alternatively, the stop 46 can also be actively moved axially, thus causing displacement of the collet 44.

(45) The collet 44 is therefore supported by means of the stop 46 and the clamping element 41 is pulled over the collet 44. As a result, the coupling 40 is opened and the valve closure 34 and its coupling pin 38 can be removed.

(46) For the insertion of a new valve closure 34, the pin 38 is inserted into the open collet 44 and the valve closure 34 is aligned in particular. To fix or lock the valve closure 34 in the coupling 40, the valve rod 35 is moved together with the inserted closure 34 along the vertical axis V upwards, i.e. into the valve-closed position. The displacement of the rod 35 occurs beyond a contact point (contact between the valve closure 34 and seal of the sealing surface 33), whereby the clamping element 41 is pushed over the movement-limited collet 44 and the coupling 40 is placed in a closed operating state.

(47) With such a changing device, the valve plate 34 can be exchanged within the process gas region with little effort and simple means. The mechanical loosening of the valve plate 34 from the valve rod 35 and the coupling thereto can occur relevantly by a targeted adjustment of the vertical axis position of the coupling 40. Another mechanical intervention (e.g. loosening and tightening of screws) in the system can therefore be avoided. The risk of unwanted particle formation is reduced accordingly. Preferably, a specific drive sequence for the drive unit 37 is provided for this purpose.

(48) It will be understood that the coupling embodiment shown or included in the present invention may be used in other types of vacuum valves of the prior art accordingly. Preferably, an arrangement for replacement and/or maintenance of a wear-prone valve closure may be appropriate. Conceivable is a corresponding arrangement of such a low-particle collet coupling which is releasable by a drive alternatively or additionally for other movable components in a vacuum processing process. Such embodiments are also encompassed by the present invention.

(49) It is understood that the illustrated figures represent only possible embodiments schematically. The various approaches according to the invention can also be combined with one another as well as with vacuum devices, in particular for substrate processing or vacuum valves of the prior art.