The present invention relates to a removal roller, to a device comprising a removal roller of this type and to a method using a device of this type for detaching a film from a disc-shaped workpiece, in particular from a mould wafer.
Although the present invention and the problem which it addresses can be applied to any disc-shaped workpieces, they will be described in detail with respect to a mould wafer.
The device according to the invention is arranged in particular in a wafer production line and is used to detach and separate a film from a disc-shaped workpiece, in particular from a mould wafer or a compound wafer. A mould wafer or compound wafer is a composite wafer which is produced by assembling individual chips, for example silicon chips, into a wafer-shaped structure, the chips being bonded together by a plastics material to form a disc-shaped structure. In the course of various working steps for the production of a wafer of this type, films are applied, in particular affixed or attached enduringly by an adhesive effect to disc-shaped workpieces. These films have a self-adhesive characteristic. The films are used, for example as protective and cover films during individual processing steps, but they can also be functionally significant for the processing of the workpieces, for example for fixing individual workpiece parts or as bilateral adhesive supports for the adhesive treatment and for transporting the workpiece by machine tools.
Before the mould wafer is finished, it is necessary, particularly in an assembly line-type processing method, to detach the film from the mould wafer as carefully and reliably as possible and as far as possible without any remainder, particularly at a high speed and with great dependability.
This object is achieved by a removal roller which has the features of claim 1 and/or by a device which has the features of claim 4 and/or by a method which has the features of claim 9.
According thereto, the following are provided:
A removal roller for detaching a film from a disc-shaped workpiece, in particular from a compound wafer, comprising a film handling portion for non-positively taking up or expelling a portion of the film.
A device for detaching a film from a disc-shaped workpiece, in particular from a compound wafer, comprising: a mounting means for non-positively mounting the disc-shaped workpiece; a removal roller with a film handling portion for non-positively taking up or expelling a portion of the film; a displacement means for moving the removal roller horizontally and/or vertically to a surface of the mounting means; and a rotation means for rotating the removal roller about a centre axis of the removal roller.
A method for detaching a film from a disc-shaped workpiece, in particular from a compound wafer, using a device of this type, comprising the following steps: moving the removal roller horizontally from a parking position into a take-up position of the removal roller, the film handling portion facing the film in the parking position; activating the film handling portion and vertically lowering the removal roller onto the film; affixing the portion of the film on the removal roller; vertically raising the removal roller from the disc-shaped workpiece, the portion of the film being detached at least progressively from the disc-shaped workpiece; rotating the removal roller by a predetermined wrap angle to at least progressively wind up the portion of the film onto the removal roller and simultaneously moving the removal roller horizontally in the direction of the parking position, the film being progressively detached from the disc-shaped workpiece; vertically moving the removal roller away from the disc-shaped workpiece, simultaneously with the horizontal movement, as far as a horizontal end position of the removal roller; horizontally moving the removal roller beyond the parking position into an expulsion position, the film being completely detached from the disc-shaped workpiece in the expulsion position; unwinding the portion of film, wound onto the removal roller, from the removal roller by rotating the removal roller in the opposite direction by a portion of the predetermined wrap angle such that the film handling portion is positioned in a discharge position; and expelling the film from the removal roller by the film handling portion. In this respect, the film, in particular a portion of the film adheres to the removal roller by means of the film handling portion of the removal roller. A horizontal and vertical movement of the removal roller relative to the disc-shaped workpiece automatically detaches the film rapidly from the disc-shaped workpiece without leaving any remainder.
Advantageous configurations and developments of the present invention are provided in the subclaims and in the description, combined with the figures of the drawings.
According to a preferred development of the removal roller, the film handling portion is configured as a switchable vacuum/excess pressure portion, in particular as a suction/blowing nozzle or as a suction/blowing slot arranged along a centre axis of the removal roller, for non-positively taking up the portion of the film by a vacuum or for expelling the portion of the film by means of an excess pressure. This ensures a reliable take-up and expulsion action of the portion of film.
According to a further preferred development of the removal roller, said roller has an adhesion sensor, in particular a vacuum switch for establishing the non-positive take-up or expulsion of the portion of film by the film handling portion. Consequently, the operation of the film handling portion is monitored, thus enhancing the operational reliability of the removal roller.
According to a preferred development of the device, the displacement means comprises a horizontal displacement element for moving the removal roller horizontally to the surface of the mounting means and a vertical displacement element for moving the removal roller vertically to the surface of the mounting means. This allows the removal roller to be positioned rapidly and precisely relative to the disc-shaped workpiece.
According to a further preferred development of the device, said device comprises a heating means for heating the disc-shaped workpiece and/or the film to a predetermined temperature, in particular to a temperature between 180° C. and 240° C., thus ensuring a reliable detachment of the film from the disc-shaped workpiece.
According to a further preferred development of the device, the mounting means comprises a drive element for rotating a workpiece mount of the mounting means about an axis of rotation of the workpiece mount. This makes it possible for the workpiece mount to be rotated before the film is removed, as a result of which a detachment angle of the film from the disc-shaped workpiece can advantageously be adjusted. This facilitates the removal of the film from the disc-shaped workpiece.
According to a further preferred development of the device, said device comprises a blowing means for blowing a portion of the film projecting over the disc-shaped workpiece, said blowing means being configured such that it blows the projecting portion in the direction of the removal roller. This ensures a reliable take-up of the portion by the removal roller, thereby enhancing the reliability of the device.
According to a preferred development of the method, the rotational movement, the vertical movement and the horizontal movement of the removal roller merge into one another such that the film is detached smoothly from the disc-shaped workpiece. This reliably prevents remnants of the film from remaining on the disc-shaped workpiece or the disc-shaped workpiece will be damaged.
According to a further preferred development of the method, the film is removed from the disc-shaped workpiece at a predetermined temperature, in particular at a temperature of 180° C. to 240° C. This ensures a simple and complete detachment of the film from the disc-shaped workpiece.
According to a further preferred development of the method, a portion of the film, projecting over the disc-shaped workpiece is blown in the direction of the removal roller by a blowing means for affixing the portion of the film to the removal roller. This provides a straightforward take-up of the portion of film by the removal roller, thereby enhancing the reliability of the method.
According to a further preferred development of the method, an angle of 180° is selected as the wrap angle. This reliably ensures that the portion of film slips off the removal roller.
According to a further preferred development of the method, the workpiece mount of the mounting means is rotated by a removal angle before the film is removed. Consequently, a detachment angle of the film from the disc-shaped workpiece can advantageously be adjusted, thereby facilitating and accelerating the detachment of the film from the disc-shaped workpiece.
According to a further preferred development of the method, the expulsion of the film from the removal roller into a film disposal means is monitored by an expulsion sensor, in particular by a light grid, of the film disposal means. Consequently, it is possible to reliably detect a film which has not been detached from the removal roller, as a result of which the malfunction susceptibility of the method is reduced.
In the following, the invention will be described in more detail on the basis of embodiments with reference to the accompanying figures of the drawings, in which:
In the figures, the same reference signs denote the same or functionally identical components, unless indicated otherwise.
The device 1 also comprises a removal roller 12 which is configured, for example in the form of a hollow cylinder with a centre axis 25. The removal roller 12 preferably has a film handling portion 13 which is configured to non-positively take up or expel the film 2, in particular a portion 14 of the film 2. The portion 14 of the film 2 is, for example, an end portion 14 or a peripheral portion 14 of the film 2. The portion 14 of the film 2 can, for example, project laterally over the disc-shaped workpiece 3 and/or over the workpiece mount 5. The film handling portion 13 is preferably configured as a switchable vacuum-excess pressure portion 13. Alternatively, the film handling portion 13 can be configured as a clamping means with a clamping gripper for gripping the film 2. For example, as illustrated in
Furthermore, the device 1 preferably comprises a displacement means 17 for moving the removal roller 12 horizontally and/or vertically to the surface 10 of the mounting means 4. The displacement means 17 preferably comprises a horizontal displacement element 18 for moving the removal roller 12 horizontally to the surface 10 of the mounting means 4. The horizontal displacement element 18 preferably has a guide profile 19 which can be moved linearly, for example relative to a fixed frame profile 20 of the device 1. A linear movement of the profiles 19, 20 relative to one another is realised, for example by an electric motor. The device 1 preferably comprises two horizontal displacement elements 18 which are each positioned bilaterally on end portions of the removal roller 12. The displacement means 17 preferably also comprises a vertical displacement element 21 for moving the removal roller 12 vertically to the surface 10 of the mounting means 4. The vertical displacement element 21 comprises, for example, a sliding body 23 which can be displaced linearly along a guide profile 22. The sliding body 23 can be moved relative to the guide profile 22, for example by an electric motor. The guide profile 22 is mounted, for example, on the guide profile 19 of the horizontal displacement element 17. The device 1 preferably comprises two vertical displacement elements 21 which are each arranged on the end portions of the removal roller 12. The removal roller 12 is preferably mounted in the sliding body 23 of the vertical displacement element 21 such that it can rotate about its centre axis 25.
Furthermore, the device 1 preferably comprises a rotation means 24 for rotating the removal roller 12 about its centre axis 25. The rotation means 24 comprises, for example, an electric motor coupled with the removal roller 12. The electric motor can be actively connected to the removal roller 12, for example directly or by a reduction stage, for example by a belt drive.
The device preferably also comprises a heating means 26 for heating the disc-shaped workpiece 3 and/or the film 2 to a predetermined temperature. The film 2 is provided, for example, with a heat-sensitive adhesive layer and is affixed by this layer to the disc-shaped workpiece 3. The heating means 26 is configured, for example, as an infrared radiator 26 or as a hot air fan 26. The heating means 26 can be, for example, an integral component of the mounting means 4, for example the heating means 26 can be configured as a heating loop integrated into the workpiece support 8. Alternatively, the heating means 26 can be arranged at a distance from the mounting means 4. The heating means 26 is preferably used for heating the disc-shaped workpiece and/or the film to a temperature between 180° and 240° C.
The device 1 preferably also comprises a blowing means 27 for blowing a portion 14 of the film 2 which projects over the disc-shaped workpiece 3. The blowing means 27 is configured, for example, as an air nozzle 27 or as a plurality of air nozzles 27. The blowing means 27 deforms the portion 14 of the film 2 which projects over the disc-shaped workpiece 3 such that said portion is curved in the direction of the removal roller 12. The blowing means 27 can be integrated into the mounting means 4, for example.
In a step S2 according to
In a step S3 which is illustrated in
In a step S4, illustrated in
In a step S5, illustrated in
In a step S6, illustrated in
In a step S7, illustrated in
If in step S2, the film 2 is not taken up by the removal roller 2 or is unintentionally detached from the removal roller 12 in one of the subsequent steps of the method, this malfunction will be detected by the adhesion sensor 15 and the device emits a trouble signal, for example. A machine operator can then remove the film 2 manually, for example, and can acknowledge the fault procedure.
According to
Although the device 1 and the method for removing the film 2 have been described with the heating means 26, said heating means 26 is merely an optional component of the device 1 and/or of the method. It is possible to dispense with the heating means 26. The optional use of the heating means 26 depends, for example, on the type of adhesive layer which is used between the film 2 and the disc-shaped workpiece 3.
Number | Date | Country | Kind |
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10 2009 041 294.8 | Sep 2009 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP2010/063486 | 9/14/2010 | WO | 00 | 5/29/2012 |