SUBSTRATE RECEIVING AREA FOR PROCESS CHAMBERS

Abstract

The invention relates to a device 10 for holding workpieces 30 in a process chamber. The invention additionally relates to a coating system 20 and to a method for coating a workpiece 30. In order to allow for precise adjustment of the height of the position of workpieces 30 while supporting same in a secure and stable manner, the holding device 10 comprises a tray 72 for the workpieces 30, a height-adjustable first support element 22 and a height-adjustable second support element 48 for the tray 72, wherein each of the support elements 22, 48 comprises at least one first and one second limb element 26, 56, wherein the respective first and the respective second limb element 26, 56 are coupled so as to be pivotable relative to one another about a pivot axis X, Y, and wherein the pivot axis X of the first support element 22 is arranged at an angle to the pivot axis Y of the second support element 48.

Claims

1. A coating system, comprising a process chamber having associated coating means for producing a coating on a workpiece, a holding device for holding the workpiece in the process chamber, comprising a platform for the workpiece, a height-adjustable first support element and a height-adjustable second support element for the platform, wherein each of the support elements comprises at least one first and one second limb element, wherein the respective first and the respective second limb element are coupled so as to be pivotable relative to one another about a pivot axis, and wherein the pivot axis of the first support element is arranged at an angle to the pivot axis of the second support element, wherein the holding device is arranged so as to be displaceable between a first and a second position and wherein the holding device is arranged inside the process chamber in the first position and at least partially outside the process chamber in the second position.

2. The coating system according to claim 1, wherein the first and/or second support element comprises an adjustment element, which is designed to change the height of the support element.

3. The coating system according to claim 2, wherein the adjustment element is designed to change a pivot angle between the first and second limb element.

4. The coating system according to claim 1, wherein the first and/or second support element comprises at least one axial spring element for applying a force effect in the direction of its pivot axis.

5. The coating system according to claim 4, wherein a cone element is arranged around the pivot axis, wherein the axial spring element acts on the cone element.

6. The coating system according to claim 1, wherein a shaft element is arranged along the pivot axis, and wherein a radial spring element is arranged so as to act radially between the first and/or second limb element and the shaft element.

7. The coating system according to claim 1, wherein the first limb element is fork-shaped with a first and a second fork arm, and wherein the second limb element is engaged between the first and the second fork arm so as to be coupled with the first limb element.

8. The coating system according to claim 1, wherein the platform is adjustable sideways at least in part in a sideways direction transversely to the vertical direction.

9. The coating system according to claim 1, wherein at least the first and second limb element of the first and/or second support element consists of graphite.

10. The coating system according to claim 1, wherein the first and/or second support element comprises a third and fourth limb element in addition to the first and second limb element, wherein the third and fourth limb element are coupled so as to be pivotable relative to one another about a pivot axis, and wherein the pivot axis of the third and fourth limb element is arranged in parallel with and at a distance from the pivot axis of the first and second limb element.

11. (canceled)

12. The coating system according to claim 1, wherein the holding device is shiftably mounted on at least one roller for the displacement between the first and the second position, and wherein the roller is manufactured from graphite.

13. The coating system according to claim 1, wherein the coating means comprise filaments, which are arranged in the process chamber such that the height of the platform can be adjusted relative to the filaments in the first position.

14. A method for coating a workpiece, wherein the workpiece to be coated is arranged in a process chamber of a coating system according to claim 1 and is coated by a plasma method.

15. A device for holding workpieces in a process chamber, comprising a platform for the workpieces, a height-adjustable support element for the platform, wherein the support element comprises at least two mutually relatively movable elements that are in contact with one another and that consist of graphite.

Description

[0038] Exemplary embodiments of the invention are explained in more detail below with reference to drawings. The figures show:

[0039] FIG. 1 a perspective view of a first exemplary embodiment of a holding device,

[0040] FIG. 2 an exploded view of the holding device according to FIG. 1,

[0041] FIG. 3 a perspective view of a support element of the holding device according to FIGS. 1 and 2,

[0042] FIG. 4 a perspective view of further support element of the holding device according to FIG. 1-3,

[0043] FIG. 5 a partial section along the section line A . . . A′ in FIG. 4,

[0044] FIG. 6 a sectional view of a limb element along the section line A . . . A′ in FIG. 4,

[0045] FIG. 7, 8 partial schematic representations of a coating system having a holding device according to FIG. 1-6 in a front and side view.

[0046] FIG. 1 shows a first exemplary embodiment of a device for holding workpieces 10, in the following referred to as a holding device 10, comprising a substructure 12, a first and a second height-adjustable support element 22, 48, and a tray 72.

[0047] The support elements 22, 48, which support the tray 72, are fastened to the substructure 12.

[0048] FIG. 2 shows the holding device 10 from FIG. 1, wherein the components shown have been displaced in the directions of the arrows for the exploded view.

[0049] The substructure 12 consists of a base plate 14 and four rollers 16. The base plate 14 is a rectangular, planar graphite plate having two longitudinal sides and two short sides. Three metal fastening blocks 18a, 18b are mounted on the upper side of the base plate on both short sides as well as centrally for mounting the rollers 16 and the support elements 22, 48. The four rollers 16 are connected so as to be rotatable and, for this purpose, are each connected in pairs by means of a shaft. In each case, one shaft is attached in a fastening block 18a on a short side of the base plate 14.

[0050] The first support element 22 comprises two longitudinal support units 24 designed so as to be mirror-symmetrical, of which one is shown in FIG. 4, and comprising two longitudinal limb elements 26 and a shaft element 34.

[0051] The longitudinal limb elements 26 are each cut from a rectangular graphite plate, such that they have extensions on their longitudinal sides. Two fork extensions 28a are positioned close together so as to form a fork. A single extension 32a is arranged at a distance from the fork on the same long side.

[0052] In each case, two longitudinal limb elements 26 are coupled via the shaft element 34, in that, in each case, one single extension 32a engages between the fork extensions 28a and the shaft element 34 extends in aligned bores through the extensions 28a, 32a of both longitudinal limb elements 26. In this way, both longitudinal limb elements 26 are coupled so as to be pivotable about a longitudinal pivot axis X, in that they are interconnected in an articulated manner via the shaft element 34 arranged along the longitudinal pivot axis X, such that the angle included between them can be changed.

[0053] Two longitudinal fastening axes 36 extend through the outer longitudinal sides of both longitudinal support units 24 for pivotably attaching the first support element 22 to the substructure 12 and to the tray 72.

[0054] Axial clamping units 37, for each of which a cone 44, an axial spring 38 and a locking ring 46 cooperate, are attached to the shaft element 34 and to the longitudinal fastening axes 36. The axial clamping units 37 are, on the one hand, attached on the shaft element 34 on both outer sides of both forks (see FIG. 4) and, on the other hand, attached on the longitudinal fastening axes 36 on the outer sides of the longitudinal limb elements 26 (see FIG. 2). The axial clamping units 37 preload the articulated connections of the longitudinal limb elements on the shaft element 34 and on the longitudinal fastening axes 36 in the axial direction.

[0055] The second support element 48 comprises two transverse support units 52, which are designed to be mirror-symmetrical, and an adjustment element 54. In this regard, FIG. 3 shows a transverse support unit 52 and part of the adjustment element 54 connected thereto. The adjustment element 54 is designed to be symmetrical and the second transverse support unit 52 is attached thereto in a mirror-symmetrical manner. The transverse support units 52 each comprise two transverse limb elements 56, which are identical and also provided as graphite plates. Analogous to the longitudinal leg elements 26, two fork extensions 28b and a single extension 32b are located on their longitudinal sides.

[0056] Two screws 58 are attached along a transverse pivot axis Y so as to be spaced apart from one another in the axial direction such that two fork extensions 28b are pivotably coupled to one single extension 32b via one screw 58 in each case.

[0057] The adjustment element 54 is designed as a spindle and, on each of both sides, comprises a spindle thread 64, which engages with a threaded nut 66 in each case. In addition, a coupling element 68 (see FIG. 2) is located on one side of the adjustment element 54 in order, for example, to rotate the spindle 54 with a wrench.

[0058] The threaded nut 66 is coupled to the transverse support unit 52 in that it is arranged between the two forks of the transverse support unit 52 and is screwed from both sides by means of the screws 58. The threaded nut 66 lies on the transverse pivot axis Y, such that it is traversed centrally thereby and the axis of the adjustment element 54 is aligned perpendicularly to the axis Y. One of the two threaded nuts 66 comprises a clockwise thread and the other comprises an anticlockwise thread, such that their movements are opposed during rotation of the adjustment element 54 and they move toward one another or away from one another.

[0059] Two transverse fastening shafts 62 extend through the outer longitudinal sides of both transverse support units 24 for pivotably attaching the second support element 48 to the substructure 12 and to the tray 72.

[0060] The tray 72 comprises a fastening unit 74, an actuation unit 76 and a supporting unit 78. The supporting unit 78 lies on top on the fastening unit 74 and both enclose the actuation unit 76 within their interior.

[0061] The fastening unit 74 comprises a planar, rectangular fastening plate 82, which is manufactured from a graphite plate. It comprises three elongate recesses 84, which extend in parallel with its longitudinal sides. On the lower side of the fastening plate 82, analogous to the base plate 14, two fastening blocks 18a are located on the short sides and one fastening block 18b is located in the center of the fastening plate 82. The actuation unit 76 comprises three identical eccentric shafts 86, at the ends of which one eccentric 88 is attached in each case. All six eccentrics 88 also have the same shape.

[0062] The supporting unit 78 is composed of three individual, planar, rectangular supporting plates 92, which are also manufactured from graphite plates and have recesses in longitudinal directions on their lower side (not shown). There are multiple ridges on all three supporting plates 92 so as to form guide grooves 94 in the longitudinal direction.

[0063] The actuation unit 76 lies in the recesses of the fastening unit 84 and of the supporting unit 78, such that the eccentric shafts 86 can rotate and the eccentrics 88 can carry out rotational and linear movements. In each case, one supporting plate 92 lies on one eccentric shaft 86 having two eccentrics 88, such that the eccentric shaft 86 and the eccentrics 88 are located inside the recesses of the supporting plate 92. A rotation of one of the eccentric shafts 86 can therefore adjust the supporting plate 92 resting thereon relative to the fastening plate 82 in the transverse direction.

[0064] The substructure 12, the two support elements 22, 48 and the tray 72 are interconnected via the longitudinal and transverse fastening shafts 36, 62, which are rotatably mounted in fastening blocks 18a, 18b (see FIG. 1). For both longitudinal support units 24 and both transverse support units 52, in each case, one longitudinal fastening axis 36 and one transverse fastening shaft 62, respectively, are attached in an articulated manner, in a fastening block 18a, 18b on the base plate 14 and in a fastening block 18a, 18b on the fastening plate 82.

[0065] The tray 72, which is aligns in parallel with the substructure 12, can be adjusted in height by means of the second support element 48. For this purpose, its height is adjusted by means of the adjustment element 54 such that it changes the distance between the substructure 12 and the tray 72.

[0066] The height adjustability of the second element 48 is implemented by means of a toggle joint. Three shafts, i.e. the transverse pivot axis Y and the two transverse fastening shafts 62, are interconnected in an articulated manner via the transverse limb elements 56. The transverse limb elements 56 are coupled to one another and to the adjustment element 54 in the transverse pivot axis Y such that the adjustment element 54 can displace the transverse pivot axis Y translationally transversely to the direction of the height adjustment and can thus bow or stretch the articulated connection of the transverse limb elements 56. In this way, the substructure 12 and the tray 12 remain aligned and parallel to one another during height adjustment.

[0067] FIG. 5 shows a section of one of the two longitudinal limb elements 26 with the axial clamping unit 37. The cone 44 comprises a bore, which is adapted to the shaft element 34 such that the cone 44 abuts with a tight fit therearound. Furthermore, the tapered section of the cone 44 lies in a form-fitting manner in a likewise tapered material recess of the longitudinal limb element 26, such that said cone is partially enclosed by the longitudinal limb element. Outside of the longitudinal limb element 26, in cross-section, the cone 44 comprises a notch, in which said cone receives the axial spring 38 in order to hold same and thus to ensure an optimal transmission of force from the axial spring 38 to the longitudinal limb element 26. The other end of the axial spring 38 is held by an immovable locking ring 46. The axial spring 38 is preloaded between the cone 44 and the locking ring 46 such that it exerts a force in the direction of the axis X. Two axial clamping units 37 clamp the fork on both sides and center the shaft element 34 in the bores of the longitudinal limb element 26 (see FIG. 4). In this way, the backlash of the longitudinal limb elements 26, in particular in the direction of the axis X, is reduced and the friction at the joint formed by the two longitudinal limb elements 26 is increased, such that the inertia of the movements of the longitudinal limb elements 26 is increased.

[0068] FIG. 6 shows the arrangement of a radial spring 42 inside the longitudinal limb element 26, more specifically in the single extension 32a. It is attached in a bore that is oriented perpendicularly to the axis X and thus acts between the longitudinal limb element 26 and the shaft element 34. Due to it being preloaded, it also reduces the backlash and increases the friction. For the longitudinal support unit 24, a radial spring 42 is mounted in both longitudinal limb elements 26 so that they act on the shaft element 34 from opposite directions.

[0069] Radial springs 42 are also inserted in the single extensions 32a of the second support element 48 in the same way (not shown).

[0070] The first support element 22 has no height-adjusting effect for the holding device 10, but rather merely a supporting effect along the longitudinal side of the tray 72. The second support element 48, in addition to its height-adjusting effect, also has a supporting effect along the transverse sides of the tray 72. As such, the supporting forces are directed at a right angle to one another and increase the range of the directions in which backlash is reduced. The spacing between the longitudinal support units 24 and between the transverse support units 52, and the damping of the movements of the first support element 22 result in a stable hold of the tray 72 without wobbling.

[0071] FIGS. 7 and 8 schematically show how the holding device 10 can be used in a coating system 20.

[0072] The coating system 20 is designed for hot-wire-activated CVD coating methods. Filaments 96 are attached in two mutually parallel planes and are aligned perpendicularly to the tray 72.

[0073] FIG. 7 shows a row of workpieces 30 that are being held by the holding device 10 between the two planes of filaments 96. The guide grooves 94 hold a workpiece holder with the workpieces 30 firmly in an upright position. On account of the abovementioned height and lateral adjustability, the workpieces 30 can be precisely positioned such that they are arranged exactly between the two planes and are subjected to the localized high temperatures of, for example, 600° C. locally generated by means of the filaments. Workpieces may also be arranged on the other supporting plates 92.

[0074] In order to mount the workpieces 30 on the holding device 10 or to remove them after a coating process, the holding device 10 is located in an equipping position and is rolled out of the coating system 20 on a pull-out base for this purpose. In order to coat the workpieces 30, the holding device 10 is fully rolled into the inside of the coating system 20 and is located in a coating position. The pull-out base is also pushed in. On account of the arrangement of the support elements 22, 48 and the preloading of the articulated connections, a switch between the equipping and the coating position takes place with movements involving little backlash.

LIST OF REFERENCE SIGNS

[0075] 10 Holding device [0076] 12 Substructure [0077] 14 Base plate [0078] 16 Roller [0079] 18a, b Fastening blocks [0080] 20 Coating system [0081] 22 First support element [0082] 24 Longitudinal support unit [0083] 26 Longitudinal limb element [0084] 28a Fork extensions of the first support element [0085] 28b Fork extensions of the second support element [0086] 30 Workpiece [0087] 32a Single extension of the first support element [0088] 32b Fork extensions of the second support element [0089] 34 Shaft element [0090] 36 Longitudinal fastening axis [0091] 37 Axial clamping unit [0092] 38 Axial spring [0093] 42 Radial spring [0094] 44 Cone [0095] 46 Locking ring [0096] 48 Second support element [0097] 52 Transverse support unit [0098] 54 Adjustment element [0099] 56 Transverse limb element [0100] 58 Screw [0101] 62 Transverse fastening shaft [0102] 64 Spindle thread [0103] 66 Threaded nut [0104] 68 Coupling element [0105] 72 Tray [0106] 74 Fastening unit [0107] 76 Actuation unit [0108] 78 Supporting unit [0109] 82 Fastening plate [0110] 84 Recess in the fastening plate [0111] 86 Eccentric shaft [0112] 88 Eccentric [0113] 92 Supporting plate [0114] 94 Guide groove [0115] 96 Filament [0116] 98 Junction box [0117] X Longitudinal pivot axis [0118] Y Transverse pivot axis