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Title:
DEVICE FOR TREATING A PLATE-SHAPED SUBSTRATE IN A BATH.
Document Type and Number:
WIPO Patent Application WO/2008/023974
Kind Code:
A1
Abstract:
The present invention relates to a device (1, 501) for treating a plate-shaped substrate (21) in a bath (7, 7' ' ) comprising a bath (7, 7' ' ), a process container (55, 503) for at least one substrate (21), transfer means (32,33,36,37,41,42,504,505) for automated transfer of a substrate (21) from a collecting container (14) for a row of a number of substrates (21) to the process container (55, 503), positioning means (11-13, 16-18, 22, 23) for positioning the collecting container (14), conveying means (5, 6, 502) for carrying the process container (55,503) with at least one substrate (21) present therein into and out of the bath (7,7' '), and control means for controlling the device (1,501), wherein the positioning means (11-13, 16-18, 22, 23) are arranged for positioning a collecting container (14) under the process container (55, 503), in such a manner that substrates (21) present in the collecting container (14) are at least substantially vertically oriented, and wherein the transfer means (32, 33, 36, 37, 41, 42, 504, 505) are arranged for carrying a substrate (21) upwards in a direction of movement from the collecting container (14) to the process container (55, 503) via an open upper side of the collecting container (14).

Inventors:
LANGEREIS RONALD (NL)
VAN HINTUM GERARDUS JOHANNES (NL)
Application Number:
PCT/NL2007/000155
Publication Date:
February 28, 2008
Filing Date:
June 22, 2007
Export Citation:
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Assignee:
MECO EQUIP ENG (NL)
LANGEREIS RONALD (NL)
VAN HINTUM GERARDUS JOHANNES (NL)
International Classes:
C25D7/12; C25D9/02; C25D17/06; H01L21/00; H01L21/677; C23C18/16; H05K3/18
Domestic Patent References:
WO1999004416A11999-01-28
WO2005042804A22005-05-12
Foreign References:
EP0846790A21998-06-10
US20050092600A12005-05-05
US20030051973A12003-03-20
JPS60157230A1985-08-17
US20030051972A12003-03-20
Attorney, Agent or Firm:
DOHMEN, Johannes, Maria, Gerardus et al. (P.O. Box 645, AP Eindhoven, NL)
Download PDF:
Claims:
CLAIMS

1. A device for treating a plate-shaped substrate in a bath, comprising a process container for at least one substrate, transfer means for automated transfer of the substrate from a collecting container for a row of a number of substrates to a process container, positioning means for positioning the collecting container, conveying means for carrying the process container with at least one substrate present therein into and out of the bath, and control means for controlling the device, characterised in that the positioning means are arranged for positioning a collecting container under the process container, in such a manner that substrates present in the collecting container are at least substantially vertically oriented, and in that the transfer means are arranged for carrying a substrate upwards in a direction of movement from the collecting container to the process container via an open upper side of the collecting container. 2. A device according to claim 1 , characterised in that the transfer means comprise a supporting arm, on an upper end of which a substrate can be supported, and which is arranged for receiving a substrate via an opening in the bottom of the collecting container during upward movement of the supporting arm in the direction of movement. 3. A device according to claim 2, characterised in that the supporting arm is provided with a groove at the upper end for receiving a lower part of the circumferential edge of the substrate therein.

4. A device according to claim 2 or 3, characterised in that the supporting arm is arranged for carrying a substrate all the way from the collecting container to the process container during the upward movement of the supporting arm for transferring a substrate to the process container.

5. A device according to claim 2, 3 or 4, characterised in that the supporting arm is arranged for carrying a substrate all the way from the process container into the collecting container during downward movement of the supporting arm for transferring a substrate to the collecting container.

6. A device according to any one of the preceding claims, characterised in that the positioning means comprise translation means for translating the collecting container in the longitudinal direction of the row of substrates in the collecting container.

7. A device according to any one of the preceding claims, characterised in that the direction of movement includes an angle of 0-30 degrees, preferably 1-10 degrees, with the vertical.

8. A device according to any one of the preceding claims, characterised in that the process container and the collecting container are pivotable between an inclined position, in which a substrate in the process container and in the collecting container includes an angle of 0-30 degrees, preferably 1-10 degrees, with the vertical, and a vertical position, in which the substrate in the process container and in the collecting container extends vertically. 9. A device according to any one of the preceding claims, characterised in that said conveying means comprise a horizontal longitudinal guide for conveying a process container with a substrate present therein in horizontal direction towards and away from a position above the bath.

10. A device according to any one of the preceding claims, characterised in that said conveying means comprise a vertical guide for conveying a process container with a substrate present therein in vertical direction.

11. A device according to any one of the preceding claims, characterised in that the device is provided with switchable coupling means for temporarily coupling the process container to the conveying means. 12. A device according to any one of the preceding claims, characterised in that the process container comprises a first process container portion comprising a supporting element having a supporting surface, whilst the control means are arranged for successively controlling the transfer means to carry a substrate upwards in the direction of movement to an uppermost position, such that the substrate completely passes at least the supporting surface, seen in the direction of movement, controlling the first process container portion to move towards the substrate, in such a manner that the supporting surface is positioned under the substrate, seen in the direction of movement, and controlling the transfer means to lower the substrate from the uppermost position, in such a manner that the substrate Will be supported on the supporting surface.

13. A device according to claim 12, characterised in that the supporting surface. is made up of an inner, curved flank of a strip-shaped part, whose radius of the curvature is the same as that of a substrate, said strip-shaped part being connected at an upper end thereof to the first process container portion and being

provided at a lower end thereof with a stop surface facing towards the substrate, against which the substrate can abut.

14. A device according to claim 13, characterised in that the strip- shaped part is curved in a direction away from the first process container portion from the upper end in the open condition of the process container and is pressed to a flat configuration in the closed condition, with the strip-shaped part being positioned at the outer circumference of the substrate.

15. A device according to any one of the claims 12, 13 or 14, characterised in that the first process container portion comprises two supporting elements arranged in mirror symmetry.

16. A device according to claim 12, 13, 14 or 15, characterised in that the process container comprises a second process container portion, with the first process container portion and the second process container portion being movable towards and away from each other between, respectively, a closed position of the process container, in which a substrate is present in the process container, and an open position of the process container, in which a substrate can be placed into the container and/or be removed therefrom.

17. A device according to claim 16, characterised in that the second process container portion comprises retaining means for retaining a part of the circumferential edge of a substrate in a direction perpendicular to the plane of the substrate in the uppermost position of the substrate.

18. A device according to any one of the claims 12-17, characterised in that the process container comprises contact means for making electrically conductive contact with a substrate in the process container for the purpose of applying an electric voltage to the substrate when the substrate present in the process container is immersed in the bath.

19. A device according to any one of the claims 1-11 , characterised in that the process container comprises sealing means for realising a liquid-tight seal between the contact means and the environment of the process container. 20. A device according to any one of the claims 1-11 , characterised in that the process container comprises a number of clamping elements provided along the circumference of a substrate for clampingly engaging the substrate. 21. A device according to claim 20, characterised in that said clamping means are arranged for making electrically conductive contact with a substrate in

the process container for the purpose of applying an electric voltage to the substrate when the substrate present in the process container is immersed in the bath. 22. A process container for use in the device according to any one of the preceding claims.

Description:

Device for treating a plate-shaped substrate in a bath.

DESCRIPTION

The present invention relates to a device for treating a plate-shaped substrate in a bath, comprising a process container for at least one substrate, transfer means for automated transfer of a substrate from a collecting container for a row of a number of substrates to the process container, positioning means for positioning the collecting container, conveying means for carrying the process container with at least one substrate present therein into and out of the bath, and control means for controlling the device.

The aforesaid treatments may for example comprise electro- coating, wherein a coating is applied to a substrate, such as a wafer, by means of an electrode-position process. Another form of treatment is metal plating, wherein a metal film is electrolytically precipitated on a substrate, such as a wafer, or at least on parts thereof. In the case of an electrolytic treatment, use is made of an electrolytic bath in which the substrate is immersed. The present invention may also be used for other types of treatment, however, such as the cleaning or etching of substrates in a chemical bath or the currentless deposition of a film thereon.

International patent application W0-A1 -99/04416 describes a device in which wafers are moved vertically upwards from a collecting container to the beginning of a stationary sloping track, over which the wafers subsequently roll down through a number of stations. In said stations, the rolling motion of the wafers is interrupted by means of operable stops and the wafers are cleaned in particular by being sprayed. European patent application EP-A2-846 790 describes a system in which wafers are jointly pressed upwards from a collecting, container, said wafers being supported on a holder which is provided with grooves for each of the wafers. Subsequently, a robot carries the wafers one by one to respective stationary process containers in an anodic bath. A device according to the introductory paragraph is known from

International patent application WO-A2-2005/042804. Said document describes a production system by means of which workpieces can be delivered to a workpiece holder from an automated loading station. The workpiece holder can subsequently be carried to one or a number of process modules by means of a conveying system,

in which process modules the workpiece can be subjected to an electrolytic treatment. The patent application in question mentions as an exemplary production system the Stratus System from NEXX Systems, Inc. in Billerica, MA. In the Stratus system, insofar as it is used in combination with an automated loading station, a horizontally oriented substrate is taken from a collecting container and placed into a process holder by a three-axis robot. The process holder is subsequently rotated from a horizontal orientation to a vertical orientation and delivered to a process module by a three-axis robot. Treating a substrate in a vertical orientation thereof has various advantages form the viewpoint of process technology. In addition to that, the required floor area can be significantly reduced if the substrates are treated in a vertical rather than a horizontal orientation thereof.

The object of the present invention is to provide a device according to the introductory paragraph by means of which the aforesaid advantages can be obtained, but which moreover has a low cost price in spite of the fact that the device according to the invention comprises means for the automated transfer of a substrate from a collecting container to a process container. In order to accomplish that object, the device according to the invention is characterised in that the positioning means are arranged for positioning a collecting container under the process container, in such a manner that substrates present in the collecting container are at least substantially vertically oriented, and in that the transfer means are arranged for carrying a substrate upwards in a direction of movement from the collecting container to the process container via an open upper side of the collecting container. This achieves that a minimum amount of manipulation is required for transferring the substrate from the collecting container to the process container on one hand and for carrying the process container with a substrate present therein into an out of the bath, so that the device according to the invention can be of relatively simple design whilst taking up a small amount of floor space.

The constructional simplicity is in particular relevant if the transfer means comprise a supporting arm, on an upper end of which a substrate can be supported, and which is arranged for receiving a substrate via an opening in the bottom of the collecting container during upward movement of the supporting arm in the direction of movement.

In order to be capable of supporting a substrate in a reliable manner, the supporting arm is preferably provided with a groove at the upper end for

receiving a lower part of the circumferential edge of the substrate therein. Such a groove is preferably provided with locating edges.

The supporting arm is utilised very advantageously if the supporting arm is arranged for carrying a substrate all the way from the collecting container to the process container during the upward movement of the supporting arm for transferring a substrate to the process container, and/or if the supporting arm is arranged for carrying a substrate all the way from the process container into the collecting container during downward movement of the supporting arm for transferring a substrate to the collecting container. In order to be able to present several substrates in the collecting container or empty positions in the collecting container to the transfer means in a constructionally simple manner, a preferred embodiment is characterised in that the positioning means comprise translation means for translating the collecting container in the longitudinal direction of the row of substrates in the collecting container.

According to a very advantageous preferred embodiment, the direction of movement includes an angle of 0-30 degrees, preferably 1-10 degrees, with the vertical, and thus the direction of movement is not an exactly vertical direction of movement, although this possibility is not excluded within the framework of the present invention. The inclination of the direction of movement enables the transfer means to handle the substrate in an unequivocally defined position and orientation thereof, viz. inclined in the same direction at all times.

In particular within the framework of the above preferred embodiment it is furthermore preferable if the process container and the collecting container are pivotable between an inclined position, in which a substrate in the process container and in the collecting container includes an angle of 0-30 degrees, more preferably of 1-10 degrees, with the vertical, and a vertical position, in which the substrate in the process container and in the collecting container extends vertically. Thus a reliable transfer by the transfer means to the process container or possibly the collecting container can take place in the inclined position, whilst in the exactly vertical position a process container with a substrate present therein can be presented to the conveying means in an advantageous manner.

Said conveying means preferably comprise a horizontal longitudinal guide for conveying a process container with a substrate present therein in

horizontal direction towards and away from a position above the bath, and/or a vertical guide for conveying a process container with a substrate present therein in vertical direction. The latter makes it possible in a simple manner to immerse a filled process container in a bath and/or to present a process container for delivering or receiving a substrate.

The device is furthermore preferably provided with switchable connecting means for temporarily connecting the process container to the conveying means. This makes it possible to use the conveying means in an efficient manner for manipulating several process containers. Thus it is conceivable, for example, that the conveying means place a first process container into a first bath, subsequently pick up the first process container again and finally carry the substrate that is present therein back to a collecting container again.

To enable the transfer of a substrate between the transfer means and the process container, the process container preferably comprises a first process container portion comprising a supporting element having a supporting surface, whilst the control means are arranged for successively controlling the transfer means to carry a substrate upwards in the direction of movement to an uppermost position, such that the substrate completely passes at least the supporting surface, seen in the direction of movement, controlling the first process container portion to move towards the substrate, in such a manner that the supporting surface is positioned under the substrate, seen in the direction of movement, and controlling the transfer means to lower the substrate from the uppermost position, in such a manner that the substrate will be supported on the supporting surface. In this way the transfer of a substrate between the collecting container and the process container can be effected with technically simple means. It is explicitly noted that this preferred embodiment relates not only to the situation in which the first process container portion is moved to the substrate, but alternatively, or in combination therewith, also to the situation in which the substrate is moved to the first process container portion. What is important is that eventually a situation is obtained in which the supporting surface is positioned under the substrate, seen in the direction of movement.

Specifically for use with disc-shaped substrate, it is preferable if the supporting surface is made up of an inner, curved flank of a strip-shaped part, whose radius of the curvature is the same as that of a substrate, said strip-shaped

part being connected at an upper end thereof to the first process container portion and being provided at a lower end thereof with a stop surface facing towards the substrate, against which the substrate can abut, wherein furthermore preferably the strip-shaped part is curved in a direction away from the first process container portion from the upper end in the open condition of the process container and is pressed to a flat configuration in the closed condition, with the strip-shaped part being positioned at the outer circumference of the substrate. Thus the strip-shaped part also contributes towards effecting an unequivocal position of a substrate in the process container in the closed condition thereof, because the substrate is partially retained by the curved, strip-shaped part in its own plane.

The latter effect is enhanced if the first process container portion comprises two supporting elements arranged in mirror symmetry, which furthermore makes it possible to realise a more stable support.

To effect a stable retainment of a substrate in a process container, it is preferable if the process container comprises a second process container portion, with the first process container portion and the second process container portion being movable towards and away from each other between, respectively, a closed position of the process container, in which a substrate is present in the process container, and an open position of the process container, in which a substrate can be placed into the container and/or be removed therefrom.

To effect a reliable transfer of a substrate between the process container and the collecting container by the transfer means, the second process container portion preferably comprises retaining means for retaining a part of the circumferential edge of a substrate in a direction perpendicular to the plane of the substrate in the uppermost position of the substrate. Said retaining means may be of at least substantially the same construction as a supporting element, for example comprising a strip-shaped part having a curved inner flank, whose radius of curvature is identical to that of a substrate, and a stop surface facing towards the substrate at one end of the strip-shaped part. To carry out the treatment in question in a bath, the process container preferably comprises contact means for making electrically conductive contact with a substrate in the process container for the purpose of applying an electric voltage to the substrate when the substrate present in the process container is immersed in the bath.

In particular for use in an electroplating process, the process container preferably comprises sealing means for realising a liquid-tight seal between the contact means and the environment of the process container.

In particular for use in an electrodepositing process, the process container preferably comprises a number of clamping elements provided along the circumference of a substrate for clampingly engaging the substrate. This preferred embodiment may be of constructionally very simple design.

Said clamping means are preferably arranged for making electrically conductive contact with a substrate in the process container for the purpose of applying an electric voltage to the substrate when the substrate present in the process container is immersed in the electrolytic bath. This will mean that the clamping elements are also at least partially electrocoated (unless the parts in question are masked, which would make the process container constructionally more complex again, whilst furthermore the substrate would be partially masked), which is less objectionable, since such a coating is relatively easy to remove.

The invention also relates to a process container for use in a device according to the invention..

The invention will be explained in more detail hereinafter by means of a description of two preferred embodiment of a device according to the invention, in which reference is made to various figures.

Description of the figures

Figure 1 is an isometric view of a part of a first preferred embodiment of a device according to the invention;

Figures 2-20 are partial, vertical longitudinal sectional views showing 19 successive steps during the use of the device according to the first preferred embodiment;

Figure 21 is an isometric view of the table and a process container forming part of the device during the step that is shown in figure 16;

Figure 22 is a side elevation of the process container with part of its surroundings;

Figure 23 is a vertical cross-sectional view of the process container;

Figure 24 is an exploded view of the process container;

Figure 25 is an isometric view of an outer ring of the process container with a wafer;

Figure 26 is a partial, vertical longitudinal sectional view of another part of the device according to the first preferred embodiment of the invention;

Figure 27 is a view of a second preferred embodiment of a device according to the invention; Figure 28 is a more detailed view of a part of figure 27; and

Figure 29 is a side elevation of the process container of figure 28, including the surroundings thereof.

Figure 1 shows a first part of a first preferred embodiment of a device 1 according to the invention for electrolytically treating plate-shaped substrates. In figure 2 the device 1 is shown in vertical longitudinal sectional view, albeit in a different condition, namely in a condition that can be regarded as an initial condition. Figure 26 shows a second part of the device 1.

The device 1 comprises a frame 2 supported inter alia on legs 4, a table 3 yet to be described in more detail, which can be manipulated with respect to the frame 2, a robot arm 5 and a transfer element 6 that can be transferred between the robot arm 5 and the table 3. The device 1 further comprises a number of electrolytic baths 7 (figure 26) located to the left of the part of the device 1 that is shown in figure 1. Various plates 8 are attached to the frame 2, which plates hide an internal portion of the device 1 from view. Said internal portion inter alia comprises a part of the table 1 , which part can be distinguished at least in figures 2-21.

The table 3 comprises a tabletop 11. Mounted to the upper side of the tabletop 11 are two parallel longitudinal guides 12, along which a carrier 13 for a collecting container 14 can be reciprocally moved as indicated by the double arrow

15. During said movement, guide shoes 16 on the underside of the carrier 13 guidingly interact with guides 12. To move the carrier 13 with the collecting container

14 present thereon reciprocally as indicated by the double arrow 15, the underside of the carrier 13 is connected, via a connecting piece 17, to an actuator configured as an electrically driven ball circulating screw 18, which is connected to the tabletop

11. The connecting piece 17 extends through a passage in the tabletop 11 , which passage is not shown in figure 1.

The collecting container 14 is a container for so-called wafers 21 , which is well-known to those skilled in the art in various embodiments thereof. The exact embodiment of the collecting container 14 is not relevant within the framework of the present invention. What is important, however, is that the at least substantially

disc-shaped, plate-shaped wafers 21 are contained side by side in the collecting container 14 without making contact with each other, and that the collecting container 14 has an open upper side, as well as an opening centrally provided in the underside of the collecting container 14 along the entire length of the row of wafers 21 , so that access can be gained to the individual wafers 21 in the collecting container 14 from below. Within this framework it is important to note that also the carrier 13 is provided with a central, vertical passage, whose dimension is at least substantially the same as that of the opening in the underside of the collecting container 14. The tabletop 11 with the associated parts of the device 1 is pivot- mounted to the frame 2 on one side of the tabletop 11 by means of pivot pins 22. At the opposite side of the tabletop 11 a pneumatic cylinder 23 is provided, which is operative between the frame 2 and the tabletop 11 for pivoting the tabletop 11 about the pivot pin 22 (see figure 7, for example). A gap-like passage 31 is provided centrally between the longitudinal guides 12 in the tabletop 11 (see also figure 21), through which passage an arm 32 extends. In figure 2 the arm 32 is shown in a lowermost position thereof. In said lowermost position, the upper side 33 of the arm 31 is still positioned just below the level of the bottom sides of the wafers 21. This makes it possible to position any desired wafer 21 directly above the upper side 33 of the arm 32 by moving the carrier 13 with the collecting container 14 present thereon to the left, seen in figure 2, which is done by suitably operating the pneumatic cylinder 18. To that end a significant part of the carrier 13 is hollow, comprising a cavity 34 capable of accommodating the arm 32. Said cavity 34 is closed by a closing plate 35 at the end remote from the arm 32 in figure 2. As a result, the carrier 13 is U-shaped, seen in horizontal cross-sectional view, over at least the larger part of its height, as is shown for the bottom plate the 13a of the carrier 13 in figure 21.

The bottom side of the arm 32 is connected, via a connecting piece 41 , to a lower end of an actuator 42, which may for example be configured as a pneumatic cylinder, a toothed belt drive or a spindle, and which may itself be rigidly connected, via a connecting piece 43, to the bottom side of the tabletop 11. The arm can be moved up and down as indicated by the double arrow 44 by suitably driving the actuator 42.

At the upper side 33 the arm 32 is provided with a slot 36 with

sloping locating edges 37 at the upper side (figure 22). The width of the slot 36 is to a very limited extent larger than the thickness of the wafers 21 , so that a bottom side of a wafer 21 can be received in the slot 36 with a small amount of play. The depth of the slot 36 has been selected so that the arm 32 is capable of independently carrying a wafer 21 , with the wafer 21 in question extending in line with the arm 32.

At the outer sides of the longitudinal guides 12, in line with the elongated shape of the passage 31 , the table 3 comprises two columns 51 (see in particular figure 21 ). A girder 51 is supported on the upper sides of the columns 51 , which girder forms part of the transfer element 6. Positioning pins 56 are provided on the upper sides of the columns 51 for correctly positioning the transfer element 6 with respect to the columns 51 and also with respect to the table 3, which positioning pins 56 fall into recesses in the underside of the girder 52. The transfer element 6 further comprises a connecting piece 53, by means of which the transfer element 6 can be (temporarily) connected to the robot arm 5, a connecting arm 54 extending downwards from the girder 52, and a process container 55, which is connected to the girder 52 of the transfer element 6 via the connecting arm 54. A more detailed explanation of the process container 55 will be given yet hereinafter, in particular with reference to figures 22-25. For the time being it suffices to note that the process container 55 is suitable for carrying a wafer 21 , which wafer 21 is taken from the collecting container 14, and that the transfer of the wafer 21 between the collecting container 14 and the process container 55 takes place inter alia by means of an arm 32, which is shown in a low position thereof in figure 21.

Two respective pin members 61 extend through the columns 51 , which pin members are capable of sliding movement in their longitudinal direction within the columns 51 , to which end the columns 51 comprise slide bearings 62.

The table 3 further comprises a cross-shaped element 63 having two horizontal arms 64, an upwardly extending arm 65 and a downwardly extending arm 66. The ends of the horizontal arms 64 are rigidly connected to ends of the pin members 61. Compression springs 67 are provided around the pin members 61 between the columns 51 and the horizontal arms 64. At the sides of the pin members 61 opposite the compression springs 67, the pin members 61 are provided with vertical, through slots 68. At the ends of the slots 58 remote from the columns 51 , cam wheels 69 being rotatable about horizontal axes of rotation are provided within the slots 68. In figure 21 , the upper ends of cam plates 70 having a cam profile 71

comprising three upwardly sloping levels extend within the slots 68. Because of the action of the compression springs 67, the cam wheels 69 press against the cam profiles 71 of the cam plates 70. The cam plates 70 are mounted on guide members 72, which are each arranged for guiding interaction with respective longitudinal guides 73, which are provided on the columns 51 along a central portion of the length thereof. The guide members 72 are further connected to pneumatic cylinders 74, which are connected to the columns 51 at their lower ends via connecting elements 75.

Starting from the situation that is shown in figure 21 , extension of the pneumatic cylinders 74 will lead to the guide members 72 being moved upward along the longitudinal guides 73, with the pin members 61 being moved outwards against the action of the compression springs 67 because of the contact between the cam wheels 69 and the cam profiles 71 and the downward slope of the cam profile 71 from the columns 51 , as a result of which the cross-shaped element 63 will move closer to the process container 55.

In the centre of the cross-shaped element 63, on the side facing towards the process container 55, a pneumatic rotary cylinder 81 is furthermore provided, by means of which an actuating arm 82 can be rotated reciprocally about an axis of rotation that extends perpendicularly to the cross-shaped element 63 through the centre of the process container 55 (see also figure 22). The actuating arm 82 is U-shaped, with the two legs 84 of the U-shape extending on two opposite outer sides of the process container 55, within the width thereof, in the situation in which the cross-shaped element 63 has at least slightly moved towards the process container 55 (as in figure 22). The grooves 85 are formed in the legs 84, into which grooves cam pits forming part of the process container 55 can fall. Thus, a part of the process container 55 that is connected to the cam pins 86 can be made to rotate along with the rotation (to a limited extent) of the actuating arm 82 for operating the process container 55, as will be explained hereinafter in the description of figures 22-26, which relate to the process container 55. Hollow fixing pins 87 extending towards the process container 55 are attached to the upright arm 65 and the suspended arm 66 of the cross-shaped element 63. Said fixing pins 87 are shown in figure 22, but they are not shown in figure 21. Figure 21 does show the fixation bore 88 in the upright arm 65, via which a fixing pin 87 is attached to the upright arm 65.

Figure 24 shows the process container 55 in exploded view (from a perspective opposed to that of the view of the process container 55 in figure 21 !), including a wafer 21. The process container 55 is largely made of an electrically non-conductive material, for example a suitable plastic. Insofar as electrically conductive parts are used, this will be explicitly mentioned hereinafter.

The process container 55 comprises a base ring 101 and two outer rings 102, 103. The base ring 101 is externally provided with the two aforesaid cam pins 86 on two opposite sides thereof. On the inner side of the base ring 101 , pairs of opposed, inwardly extending edges 104 are provided at regular intervals, between which a bayonet groove 105 extends. The bayonet grooves 105 are intended to mate with bayonet edges 106 on the outer rings 102 and 102 (only shown for the outer ring 103 in figure 24).

Disposed between the base ring 101 on the one hand and the respective outer rings 102, 103 on the other hand are electrically conductive contact rings 110, 111. The inside diameter of said contact rings 110, 111 is just a little larger than the outside diameter of a wafer 21.

The contact ring 111 has three disc-shaped contact surfaces 112, which are evenly distributed over the circumference of the contact ring 111 , which contact surface 112 extends on the inner side of the inside diameter of the contact ring 111 to a limited extent. The contact surfaces 112 are provided on the side of the contact ring 111 that faces towards the wafer 21 , so that there is (electrically conductive) contact between the contact surfaces 112 and the wafer 21 in the closed condition of the process container 55. The contact ring 111 is fixed to the outer ring 103 by means of bolts, , only three of which are shown in figure 24, whilst a rubber sealing ring 113 is clamped between the contact ring 111 and the outer ring 103. The contact ring 111 can be placed into electrically conductive contact with the structure supporting the process container 55 via contact bolts 114 provided at the upper side of the contact ring 111. The ends of said contact bolts 114 extend into a plastic-coated metal core in the connecting piece 121 (see figure 22), which metal core is in turn in electrically conductive contact with a plastic-coated metal core in the connecting arm 54. Subsequently, further electrically conductive contact can be built up via the girder 52 and connectors (not shown) that are operative at the location of the recesses in the underside of the girder 52, making it possible to connect the contact ring 111 anodically, neutrally or cathodically, depending on the

electrolytic process in which the device 1 is used. To that end positioning pins comparable to the positioning pins 56 are provided at the location of the bath 7 that is used, which pins are suitable for effecting an electrically conductive connection between the transfer element 6 and a voltage source. The contact ring 110 is fixed to the outer ring 102 by means of bolts, eight of which are (partially) shown in figure 24, whilst a sealing ring 115 comparable to the sealing ring 113 is clamped between the outer ring 102 and the contact ring 110. The contact ring 110 is different from the contact ring 111 in that it comprises evenly spaced outer contact lips 116, which extend tangentially, and inner contact lips 117, which extend radially inwards. The ends of the inner contact lips 117 are located on the inner side of the inner circumference of the contact ring 110, making contact with the wafer 21 in the closed condition of the process container 55, whilst the contact lips 117 may be slightly plastically bent in the direction of the wafer 21 in practice in order to obtain a good contact. The outer contact lips 116, which are located outside the outside diameter of the wafer 21 , are in any case plastically bent in the direction of the contact ring 11 , thus effecting a conductive contact between the outer contact lips 116 and the contact ring 111.

Furthermore, seals 121 , 122 are circumferentially provided on the respective outer rings 102 and 103. Said seals abut against opposite sides of the base ring 101 in the closed condition of the process container 55. During use of the device 1 , when the closed process container 55 with a wafer 21 present therein is immersed in an electrolytic bath 7, the seals 121 , 122 and 113, 115 prevent the contact rings 110, 111 from coming into direct conductive contact with the electrolytic bath, so that the contact rings 110, 111 are not contaminated. To maintain the wafer 21 in the correct position during the opening and closing of the process container 55, the outer ring 103 comprises two upper positioning means 131 , 132 arranged in mirror of symmetry at the upper side, on the side of the contact ring 111 that faces towards the wafer, and the outer ring 102 comprises two lower positioning means 133, 134 on the side of the contact ring 110 that faces towards the wafer 21. The lower positioning means 133 and 134 are intended to support a wafer 21. At their upper ends, the lower positioning means 133, 134 are rigidly connected to the outer ring 102. From said connection, strip- shaped, elastic parts 135, 136 extend substantially downwards, but in addition slightly towards the wafer 21 in the open condition of the process container 55. The

strip-shaped parts 135, 136 have a curved configuration, with inner flanks 137, 138 (see also figure 23) on which the wafer 21 can be supported (see figure 25). Stop surfaces 139, 140 facing towards the centre are provided on the lower ends of the strip-shaped parts 134, 135, which stop surfaces extend within the circumference of the wafer 21. The curvature of the strip-shaped parts 135, 136 has been selected so that it corresponds to the diameter of the wafer 21 in the closed condition of the process container 55, in which the strip-shaped parts 135, 136 are pressed flat against the contact ring 110. While the strip-shaped parts 135, 136 are being pressed flat against the contact ring 110, the wafer 21 will slightly move downwards along the flanks 137, 138 until the wafer is supported on the corners formed by the lower ends of the strip-shaped parts 135, 136 and the stop surfaces 139, 140.

The upper positioning rings 131 , 132 associated with the outer ring 103 have substantially the same shape and configuration as the lower positioning means 133, 134, viz. comprising strip-shaped, inwardly bent elastic parts 141 , 142 and stop surfaces 143, 144. The stop surface 143 is slightly bent in a direction away from the wafer 21 , whilst the stop surface 144 is slightly bent in a direction towards the wafer 21. In this way the stop surfaces 143, 144 define an (inverted) V-shape, seen in side elevation, in which the upper side of the wafer 21 can be received.

Furthermore, two leaf spring members 151 , 152 are provided on the inner side of the contact ring 111 , which ensure that the wafer 21 , which has been subjected to an electrolytic treatment in an electrolytic bath 7 in a closed process container 55, will be released from the sealing ring 113 when the process container is subsequently opened.

Two conical fixing caps 153, 154 are furthermore provided at a lower and an upper position on the outer side of the outer ring 102, which fixing caps are intended to be received in the cavities of the fixing pins 87 upon movement thereof in the direction of the process container 55.

The device 1 functions as follows. Starting from the initial condition shown in figure 2, in which the transfer element 6 carrying an empty process container 55 is connected to the robot arm 5, the robot arm 5 moves in the direction indicated by the arrow 201 until the process container 55 is positioned directly above the arm 32 (figure 3). Then the carrier 13 is moved in the direction indicated by the arrow 202 by activating the actuator 18, until one of the wafers 21 (the frontmost wafer in this case) is positioned directly above the arm 32. The upper part of the arm

32 extends within the cavity 34 in the carrier 13 (figure 4) in that situation. Figure 5 subsequently shows how the robot arm 5 is lowered as indicated by the arrow 203, until the fixing caps 153, 154 are in line with the hollow fixing pins 87 and the cam pins 86 are positioned directly opposite the open ends of the grooves 85. In this situation the girder 52 is supported on the upper side of the columns 51. The robot arm 5 then moves upwards again as indicated by the arrow 204 after the robot arm 5 and the connecting piece 53 associated with the transfer element 6 have been disconnected from each other (figure 6).

Said disconnecting of the transfer element 6 from the robot arm 5 subsequently makes it possible to pivot the table 3 with the associated parts through a limited angle about the pivot pin 22 (arrow 205) by suitably actuating the pneumatic cylinder 23, so that the situation shown in figure 7 is reached. Then the empty process container 55 is opened, to which end the cam plates 7 are moved entirely upwards (arrow 206) by suitably actuating the pneumatic cylinders 74, as a result of which the cam wheels 69 make contact with the main portions of the cam profiles 71 and the cross-shaped element 63 is moved entirely towards the process container 55 (arrow 207) against the action of the compression springs 67. During said movement, the fixing caps 153, 154 in the hollow fixing pins 87 fall into the hollow fixing pins 87, and the fixing pins 86 fall into the grooves 85. Then the actuating arm 82 is pivoted clockwise, at least seen from the side of the cam plates 70 (arrow 208), through an angle of about 20° by suitably actuating the rotary cylinder 81. As a result, the base ring 101 is rotated on account of the engagement between a portion of the edges of the grooves 85 present in the legs 84 of the actuating arm 82 and the cam pins 86. The outer ring 102 does not rotate along therewith, because it is fixed in position by the fixing pins 87 via the fixing caps 153, 154, whilst the outer ring 103 does not rotate along with the base ring 101 because it is connected to the columns 51 via the connecting arm 54 and the girder 52. As a result of the rotation of the base ring 101 , the bayonet connection between the base ring 101 on the one hand and the outer rings 102, 103 on the other hand is released (figure 9), causing the cross-shaped element 63 to move back to its original position (arrow 210), now carrying along both the base ring 101 and the outer ring 102, however. In this way an opening is created between the outer ring 103 and the base ring 101 (figure 10).

When the arm 32 is moved upwards in the direction indicated by the

arrow 211 as a result of the actuator 42 being suitably activated, the underside of the frontmost wafer 21 in the collecting container 14 is received in the slot 36 at the upper side 33 of the arm 32 and subsequently moved to a position in which the wafer 21 is positioned between the outer ring 103 on the one hand and the combination of the base ring 101 and the outer ring 102 on the other hand. The upper edge of the wafer 21 extends within the inverted V-shape defined by the stop surfaces 143, 144 of the upper positioning means 131 and 132 in that situation. The inclination of the arm 32 resulting from the previous limited rotation of the table 3 ensures that an unequivocal position of the wafer 21 supported by the arm 32 (figure 11 ) is obtained. Subsequently the process container 55 must be closed again, with the wafer 21 present in the process container 55. To that end the cross-shaped element 63 is initially moved in the direction of the outer ring 103 to a limited extent (arrow 212) together with the base ring 101 and the outer ring 102, by moving the cam plates 70 upwards over half their height (arrow 213) by suitable actuation of the pneumatic cylinders 74. This leads to the situation in which the flanks 137, 138 of the lower positioning means 133, 134 come to abut against the circular lower edge of the wafer 21 (figure 12 and figure 25). This makes it possible to retract the arm 32 in downward direction again (arrow 214), with the wafer 21 moving down slightly along the flanks 137, 138 to be fully supported in the angular space between the aforesaid flanks 137, 138 and the stop surfaces 139, 140. The wafer 21 remains retained at the upper side by the upper positioning means 131 , 132 in that situation, thereby preventing the wafer 21 from tilting forwards or backwards (figures 13, 22 and 23). In order to subsequently close the process container 55 entirely, the base ring 101 and the outer ring 102 are jointly moved against the outer ring 103 (arrow 215) by moving the cam plates 70 entirely upwards (arrow 216) by suitable actuation of the pneumatic cylinders 74. The strip-shaped, curved parts 141 , 142, 135, 136 of the respective positioning means 131 , 132, 133, 134 are pressed flat in that situation, extending along the circumference of the wafer 21 (figure 14). The process container 55 is then closed again by means of the bayonet closure, which is done by rotating the actuating arm 82 back again, as indicated by the arrow 217 in figure 15.

By subsequently pivoting the table 3 back about the pivot pin 22 by suitable actuation of the pneumatic cylinder (arrow 218) and moving the actuating arm 82 away again (arrow 219), thereby releasing the engagement between the

actuating arm 82 and the process container 55, to which end the cam plates 70 are moved entirely downwards (arrow 220) by suitable actuation of the pneumatic cylinders 74 (figure 16), the transfer element 6 becomes available again for being picked up by the robot arm 5. To that end the robot arm 5 moves downwards (arrow 221) for engaging the connecting piece 53 (figure 16), and subsequently upwards again together with the transfer element 6 (arrow 222). The robot arm 5 then moves sideways (arrow 223) together with the transfer element 6 until the transfer element 6 is positioned directly above the electrolytic bath 7.

In figure 26 this is shown for the most right-hand electrolytic bath 7, whilst the robot arm 5 has also been slightly lowered already. When the robot arm 5 is lowered even further, the transfer element 6 comes to be supported on opposite edges of the electrolytic bath 7, in a manner that corresponds to the manner in which the transfer element 6 is supported on the columns 51. In this situation the process container 55 is fully immersed in the electrolytic bath, as is shown for the process container 55" in the bath 7" in figure 26. The contact rings 110, 111 do not make direct contact with the liquid of the electrolytic bath, because seals 121 , 122 and 113, 115 are used. As a result, the device 1 is in particular suitable for electroplating, as there is no risk of metallic material being precipitated on parts other than the wafer 21 itself when such a process is used, because of the screening of the contact rings 110, 111. Via the connecting arm 54, the connecting piece 121 and the contact bolts 114 an anodic or cathodic voltage (depending on the nature of the electrolytic process in question) is applied to the contact ring 111 , which voltage is transferred to the contact ring 110 via the outer contact lips 116 and to either side of the wafer 21 via the inner contact lips 117 and the contact surfaces 112. After the robot arm 5 has delivered and left a transfer element 6 with a filled process container 55 in an electrolytic bath 7, the robot arm 5 may collect a next transfer element 6' with an empty process container 55' at another location (not shown) and subsequently return to the table 3. By moving the carrier 13 with the collecting container 14, likewise in the direction indicated by the arrow 224 (figure 20), over a limited length, so that the next the wafer 21 is positioned directly above the arm 32, the wafer 21 in question is made available for being transferred to the process container 55' in a manner as already discussed in the foregoing.

Starting from the situation as shown in figure 26 it is alternatively possible for the robot arm 5, after it has left a filled process container 55 in an

electrolytic bath 7, to pick up another filled process container 55" forming part of another transfer element 6", which process container 55" has already been in the electrolytic bath 7" for some time and been subjected to the electrolytic treatment in question therein, and return it to the table 3. There the wafer 21" from the process container 55" is transferred to the collecting container 14 again. In doing so, the same procedure, albeit in reverse order, is followed as for transferring a wafer 21 from the collecting container 14 to a process container 55.

Figures 27-30 relate to a second preferred embodiment of a device 501 according to the invention, which device 501 may be considered to be a variant of the device 1 as described in the foregoing with reference to figures 1-26. Parts of the device 501 that correspond to parts of the device 1 will be indicated by the same numerals hereinafter. For reasons of efficiency said parts will not be explained again.

The device 501 is different from the device 1 in particular as regards the embodiment of the transfer element 502, more specifically of the process container 503 thereof, and also as regards the provisions that have been made for operating the process container 503 for placement of a wafer 21 therein or for delivery of a wafer 21 therefrom.

To hold a wafer 21 , the transfer element 502 is provided with three wire spring clamps 511 , 512, 513, which are provided at 9 o'clock, 12 o'clock and 3 o'clock, respectively, in the situation in which they engage a wafer 21. The wire spring clamps 511 , 512, 513 are attached to a linkage 514, which is suspended from the girder 52. The linkage comprises a vertical rod 515, which extends between the centre of the underside of the girder 52 and a position directly opposite the centre of the cross-shaped element 63. The linkage 514 further comprises a horizontal rod, which is connected at a point halfway its length to the lower end of the vertical rod 515. The two ends of the horizontal rod are bent through 90°, so that the horizontal rod is U-shaped, seen in top plan view, comprising legs 516 whose free ends extend away from the cross-shaped element 63. The web of the U-shape of the horizontal rod, which is not clearly shown as such in any one of the figures 27-30, falls into a groove 517 formed in the upper side of a strengthening block 518. Said strengthening block 518 is rigidly connected to a horizontally extending angle section 519, which extends under the wire spring clamps 511 , 513 and whose ends are rigidly connected to the columns 51. The linkage 514 further comprises a third

horizontal leg 520, which extends the same distance from the vertical rod 515 above and parallel to the legs 516.

The wire spring clamps 511 , 512, 513 are identical to each other, comprising a fixed block member 531 , which is rigidly connected to the associated three legs 516, 520, and a wire portion 532. The wire portion 532 is a bent metal spring wire. The spring wire comprises bends 541-545 (arranged in mirror- symmetric pairs) in the vertical plane. At the location of the bends 541 , 542 the wire portion 532 is rigidly connected to the linkage 514. The block member 531 has a guide function for guiding the part of the wire portion 532 that extends between the bends 543 and 544 in the longitudinal direction thereof. In addition to that, each block member comprises a stop pin 546 opposite the bend 545, which stop pin is capable of making electrically conductive contact as well as electrically insulated contact with the substrate 21. The stop pins 546 function as stops opposite a bend

545 for resiliently clamping a wafer 21 between the bend 545 of the wire portion 532 and the stop pin 546. This situation is shown in figure 29.

To accommodate a wafer 21 between the bend 545 and the stop pin

546 of the block member 531 of the respective wire spring clamps 511-513 it is necessary to clear some space first between the bends 545 and the stop pin 546 before the wafer 21 is moved upwards by means of the arm 504 in a manner that has already been explained in the description of the device 1. Pusher blocks 550 are to that end provided on the horizontal arms 64 and the vertically extending arm 65 thereof, on the side of the cross-shaped element 63 that faces towards the linkage 514, which pusher blocks extend at least opposite the bends 543. In the clamping condition of the wire spring clamps 511-513 the pusher blocks 550 are spaced from the bends 543 by some distance (figure 29). When the cross-shaped element 63 is moved in the direction of the columns 51 , however, by suitable actuation of the pneumatic cylinders 74, as already explained with reference to figure 1 , the pusher blocks 550 will push against the bends 543. As a result, the bending angle at the location of the bends 542 will be reduced and the part of the wire portion 532 located between the bends 543 and 544 will move in its longitudinal direction, being guided by the block member 531. As a result, the bends 545 and the stop pins 546 will move some distance apart, thus creating space for accommodating a wafer 21 therebetween.

The arm 504 is provided with a horizontal, C-shaped supporting part

505 at the upper end thereof, in the upper longitudinal edge of which a groove has been formed, which groove has a curvature corresponding to that of the wafer 21. By means of said arm 504 a wafer is pushed upwards from a collecting container 14, which may or may not take place in the tilted position of the table 505, until the centre of the wafer 21 is positioned directly opposite the centre of the cross-shaped element 63.

By subsequently moving the cross-shaped element 63 away from the columns 51 again, the bends 545 will clamp the wafer 21 against the stop pins 546 of the block member is 531 , after which the arm 504 may be lowered again. Because of the electrically conductive properties of the wire portions 532, a desired electrical voltage can be applied to the wafer 21 via the wire portions 532, and possibly also on two sides via the stop pins 546, during the final electrolytic process in which the wafer 21 is immersed in an electrolytic bath 7 together with the wire spring clamps 511-513. The device 501 is in particular suitable for electrolytic coating. Those skilled in the art will appreciate that in contrast to the situation with the device 1 , no screening takes place in the device 501 between the contact elements that engage the wafer 21 (the wire portions 532 and possibly the stop pins 546) for applying a certain electric voltage thereto. This implies that also the wire portions 532 and possibly the stop pins 546 will be electrolytically treated to a certain extent. It is noted in that connection that the linkage 514 as well as the block members 531 are made of an insulating material or at least coated with an insulating material. Precisely because of the fact that in addition to the electrolytic growth on the wafer 21 , electrolytic growth will also take place on the wire portions 533 and possibly on the stop pins 546, the device 501 is less suitable for electroplating, whereas it is very suitable for electrodepositing, which coating can after all be removed from the wire portions 532, and possibly from the stop pins 546, in a relatively simple manner.

Although the invention has been explained on the basis of two preferred embodiments of devices for electrolytically treating a plate-shaped substrate in the foregoing, it is explicitly noted that the device according to the invention may in principle also be used in non-electrolytic processes that use a bath, for example for cleaning or etching substrates in a chemical bath.




 
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