WO2020169439A1

WO2020169439A1 - Assembly for electrically contacting a microchip substrate

Info

Publication number: WO2020169439A1
Application number: PCT/EP2020/053716
Authority: WO
Inventors: Markus Hacksteiner
Original assignee: Markus Hacksteiner
Priority date: 2019-02-21
Filing date: 2020-02-13
Publication date: 2020-08-27
Also published as: EP3821060A1

Abstract

The invention relates to an assembly (1) for electrically contacting a microchip substrate (2) during electrolytic metallization comprising: - a holder (6) having a recess (10), to which negative pressure can be applied, for receiving the microchip substrate (2); and - a bus bar (9). An electrical contact (8) is provided, which is arranged in the region of the outer edge of the microchip substrate (2) and is electrically conductively connected to the front side of the microchip substrate (2) and to the bus bar (9). The electrical contact (8), which is designed as a ring (16) or as a plurality of strips (21), is held in contact with the microchip substrate (2) and the bus bar (9) by a layer (15), which abuts the side of the electrical contact that faces away from the microchip substrate (2). The layer (15) extends beyond the edge of the microchip substrate (2) and beyond the bus bar (9) and up to the holder (6). After the metallization, the layer (15) can be removed from the microchip substrate (2).

Description

ARRANGEMENT FOR ELECTRICALLY CONTACTING A

MICROCHIP SUBSTRATES

The invention relates to an arrangement having the features of the introductory part of claim 1.

Various metal structures that are generated by electrolytic processes are required for microchips. The

Microchips are for example based on wafers or

Panels generated.

The metal structures consist e.g. made of copper and serve

for example for the electrical wiring of components.

Known metallization systems meet the technical requirements, but the process costs are

especially with long process times or with thick ones

Metal layers (through silicon via metallization), very high.

It has already been proposed to lower the process costs the number of per time unit and per metallization basin

(Electrolyte bath) to increase the metalized microchip substrates.

In this context it has been suggested that

Arrange microchip substrates in a column ("batch") and metallize the entire column at once.

For electrolytic metallization, the microchip substrate (e.g. a wafer or a panel) must be fixed on a holder. The front side of the microchip substrate must be electrically contacted at the edge of the microchip substrate. The

The back of the microchip substrate must be protected from the electrolyte. In order to enable the metallization of several microchip substrates at the same time, the surface of the holder and the surface of the microchip substrate and the anode should be aligned with one another as well as possible and be aligned planar and parallel to one another. The surface of the

In the best case, the microchip substrate and the surface of the holder should form a plane. The surface of the anode is parallel to it.

The necessary functionalities

- fixing the microchip substrate,

- Contacting the front of the microchip substrate and

- Protect the contacts on the front of the

In the prior art, however, microchip substrates result in a topography level that contradicts the required flatness.

In the state of the art, complex measures with terminals are often used (cf. KR 2013/0018633 A).

Relevant proposals are also known from JP 2014210923 A, US 2018197729 A1 and US 2016240504 A1.

US 2015/0068890 Al shows an arrangement for electrical

Contacting a substrate in the electrolytic

Metallizing, with at least one electrical contact being provided in the area of the outer edge of the substrate, which is in electrically conductive connection with the front side of the substrate. The electrical contact is held in contact with the front side of the substrate by a layer lying on its side facing away from the substrate. US 2015/0068890 Al shows not that the substrate is a microchip substrate.

The invention is based on the object of proposing an arrangement for contacting microchip substrates in which the aforementioned topography level is reduced in size or avoided at all.

This object is achieved according to the invention with an arrangement which has the features of claim 1.

Preferred and advantageous embodiments of the invention are the subject of the subclaims.

In the inventive arrangement for electrical

Contacting a microchip substrate, at least one electrical contact is provided, which is arranged in the area of the outer edge of the microchip substrate and which is connected to the

Front of the microchip substrate is in an electrically conductive connection. The electrical contact is established by a side facing away from the microchip substrate

Layer held in contact with the front of the microchip substrate. This not only results in a good electrical contact, but also an arrangement which avoids the disadvantageous topography step given in the prior art.

In the invention the layer is a polymer film.

In one embodiment of the invention, the electrical

Contact a ring made of electrically conductive material

("Conductor"), which is preferably on the front of the

Microchip substrate protruding, and for example resting on this, has projections.

In an alternative embodiment, the electrical Contact through several, over the outer edge of the

Microchip substrate distributed strips formed from electrically conductive material. With a circular microchip substrate, these strips are preferred with respect to the

Microchip substrate aligned radially.

Both the one on the front of the microchip substrate

adjacent projections of the ring made of electrically conductive

The material ("conductor track") as well as the (radially inner) ends of the strips that lie on the front side of the microchip substrate can have ends bent towards the microchip substrate or burrs or prongs protruding towards the microchip substrate. If the free ends of the projections or the ends of the strips that rest on the microchip substrate are bent, the result is a particularly good electrical contact. The same applies if edges of the projections and / or edges of the strips have ridges or prongs protruding towards the microchip substrate.

The ridges or prongs can, for example, when punching

electrical contacts are formed in the form of the ring or strips.

In the context of the invention, the arrangement comprises a holder for the microchip substrate which has a recess in which the microchip substrate is received. To fix the

Microchip substrate in the recess is provided, for example, an opening that can be acted upon by negative pressure. The opening can be designed to communicate with grooves. The grooves comprise, for example, two or more concentric, circular grooves which are connected to one another by at least one radially extending connecting groove. So is a

Uniform application of negative pressure to the recess and secure holding of the microchip substrate in the recess of the holder are guaranteed. Further details and features of the invention emerge from the following description of preferred exemplary embodiments with reference to the drawings. It shows:

1 shows an electrolyte bath with several anodes and one above it

Substrate column,

Fig. 2 shows the electrolyte bath from FIG. 1, the

Substrate column is immersed in the electrolyte bath,

Fig. 3 shows a first embodiment of an arrangement for

Contacting a microchip substrate,

FIG. 4 shows an enlarged detail of FIG. 3,

Fig. 5 shows a further enlarged detail of FIG. 3,

Fig. 6 shows a detail of FIG. 5 on an enlarged scale,

Fig. 7 shows a single protrusion of the arrangement of FIG. 3

until 6,

Fig. 8 shows an alternative arrangement according to the invention,

Fig. 9 shows a detail of the arrangement of FIG. 8 on an enlarged scale,

10 shows a holder for a microchip substrate and

Fig. 11 shows in more detail part of the arrangement of Fig.

8 with the bracket.

1 shows how several microchip substrates 2 - held by holders 6 - are combined to form a substrate column 3, are electrically contacted and are polarized as working electrodes, for example as cathodes. Several anodes 5 are provided in the electrolyte bath 4, with the electrolyte bath 4

Process modules 25 are provided.

2 shows that the microchip substrates 2 polarized as working electrodes, for example cathodes, with their holders 6 are immersed in the electrolyte bath 4 in such a way that a working electrode, for example an anode 5, is assigned to each microchip substrate. The arrows 7 shown in FIG. 2 indicate a flow generated in the electrolyte bath symbolizes. As soon as the electrolytic metallization of the microchip substrates 2 is done, the microchip substrates 2 are removed from the electrolyte bath 4 (metallization basin) again

lifted out.

In the arrangement 1 shown in FIGS. 3 to 7, the

Holder 6 for a microchip substrate 2 is provided. In order to make electrical contact with the microchip substrate 2, a contact 8 in the form of a ring 16 made of electrically conductive material is provided. The contact 8 is electrically conductive with a

Busbar 9 connected so that the front of the

Microchip substrate 2 can be polarized during electrolytic metallization as working electrodes, for example as cathodes.

The busbar 9 is laterally out of the holder 6

led out.

It should be pointed out that the microchip substrate 2 is received in a recess 10 of the holder 6 (cf. FIGS. 5 and 6), with grooves 12 and 13 which are open to the recess 10 being provided in the bottom 11 of the recess 10 which can be acted upon with negative pressure via an opening 14 (cf. FIGS. 10 and 11).

Arranged on the ring-shaped contact 8 is a layer 15, which is ring-shaped in the example, in the form of a polymer film, which in one embodiment has adhesive on its side facing the microchip substrate 2 so that it connects to the top of the microchip substrate 2 and to the ring-shaped contact 8

("Conductor track") and can be glued to the power rail 9.

The formed in the form of a ring 16 contact 8 has not only projections 17 that radially outward on the Point out busbar 9, but also projections 18 which point inward and rest on the front side of the microchip substrate 2. In a preferred embodiment, the ring 16 ("conductor track") forming the electrical contact 8 is a copper foil. By producing the electrical contact 8, for example by punching or laser cutting, the edges, in particular the projections 18 of the electrical contact 8, can be formed. In this case, a front, free end 20 of the projections 18 in the form of a prong 19 bent towards the top of the microchip substrate 2 is also contemplated the ridges result in a good electrically conductive connection between the front side of the microchip substrate 2 of the busbar 9.

In the embodiment of an arrangement 1 according to the invention shown in FIGS. 8 and 9, the electrical contact 8 is formed by several strips 21. The strips 21 are arranged distributed over the circumference of the microchip substrate 2 and are oriented essentially radially to the latter. The strips 21 are covered by a layer 15, e.g. in the form of a polymer film, both held in contact with the top of the microchip substrate 2 and pressed against the busbar 9, so that there is a good electrically conductive connection here.

As in the embodiment shown in FIGS. 3 to 7, the layer 15 made of polymer film is also annular in the embodiment shown in FIGS. 8 and 9, extends on the inside to the microchip substrate 2 and on the outside to over the

Busbar 9 and, in one embodiment, is connected to both the microchip substrate 2 and to the busbar 9 with the aid of an adhesive.

10 and 11 is a holder 6 for a

Microchip substrate 2 shown, wherein in the recess 10, in which the microchip substrate 2 is received, annular grooves 12 are provided which are open towards the recess 10. The annular grooves 12 are radially through with one another

aligned connecting grooves 13 connected. In the middle of the recess 10, the opening 14 is provided, through which the grooves 12 and 13 can be subjected to negative pressure.

Since the recess 10 has a height that is the thickness of the

Microchip substrate 2 corresponds or substantially

corresponds, the disruptive topography level is avoided.

Instead of the layer 15 in the form of a polymer film, a layer 15 in the form of a laminate or in the form of a lacquer layer can also be provided in the arrangement 1 according to the invention. The electrical contact 8 (e.g. the ring 16 or the strips 21) is also held in electrically conductive contact on the front side of the microchip substrate 2 and on the busbar 9 by the laminate or the lacquer layer.

In the context of the invention is considered, the

to produce electrical contact 8 so that a layer 15, for example a polymer film, without being coated with adhesive, is coated with the conductor tracks forming the contact 8. Subsequently, the layer 15 provided with conductor tracks, for example the polymer film, is coated with an electrically conductive adhesive and then on the

Microchip substrate 2 and the busbar 9 attached by gluing, so that the desired electrical contact with the front of the microchip substrate 2 is given.

In the context of the invention, consideration is given to designing the layer 15 provided in the arrangement 1 according to the invention so that it can be removed so that it can be removed again after the metallization

Microchip substrate 2 can be detached. If the electrical contact 8 (for example the ring 16 or the

Strip 21) on the front of the microchip substrate

pressing layer 15 is a laminate, this can be attached to the microchip substrate 2 and to the busbar 9 by heating (at least) the side of the laminate facing the microchip substrate 2 in order to connect the electrical contact 8 to the

To press the front of the microchip substrate 2 and the power rail 9.

If the holder 6 for the microchip substrate 2 has a recess 10 to which negative pressure can be applied, there is also the advantage that the layer 15 pressing the electrical contact 8 onto the microchip substrate 2 and onto the busbar 9 can easily be pulled off, since the

Microchip substrate 2 is held on the holder 6 by negative pressure.

In the context of the invention, the layer 15 can

The arrangement 1 according to the invention can also be designed as so-called "organic electronics", in which case (only) the organic (e.g. multilayered) substrate is present on which conductor tracks are applied (e.g. printed).

In the context of the invention, it is advantageous that the layer 15, which presses the electrical contact 8 (ring 16 or strip 21) against the microchip substrate 2 and the power rail, extends outside over the power rail to the holder 9 and with the holder 6 can be glued for the microchip substrate 2, so that the back of the microchip substrate 2 is protected from the ingress of electrolyte.

Although (only) one microchip substrate 2 is arranged on the holder 6 in each of the exemplary embodiments, an embodiment is also included in the scope of the invention in which microchip substrates 2 are on both sides of the holder 6 are arranged and are metallized at the same time. In this embodiment, the holder 6 can be on both sides

Depressions 10 in which the microchip substrates 2 are received.

In the context of the invention, an embodiment in

Considered in which the layer 15 adheres to the front side of the microchip substrate 2 by adhesive structures, in particular by Van der Waal forces. It can be provided that the electrical contacts 8 are applied to the adhesive structures, in particular by sputtering.

In summary, an embodiment of the invention can be described as follows:

An arrangement 1 for electrically contacting a

Microchip substrate 2 during electrolytic metallization comprises a holder 6 with a vacuum

actable recess 10 for receiving the

Microchip substrate 2 and a busbar 9. An electrical contact 8 is provided, which is arranged in the area of the outer edge of the microchip substrate 2 and is in electrically conductive connection with the front side of the microchip substrate 2 and with the busbar 9. As a ring 16 or as one

The electrical contact 8 formed by a plurality of strips 21 is held in contact with the microchip substrate 2 and the busbar 9 by a layer 15 resting on its side facing away from the microchip substrate 2. The layer 15 extends over the edge of the microchip substrate 2 and the busbar 9 and extends to the holder 6. After

The layer 15 can be detached from the microchip substrate 2 by metallization.

Claims

Expectations :

1. Arrangement (1) for electrical contacting at least

a microchip substrate (2), such as wafer or panel, during the electrolytic metallization of a microchip substrate (2), at least one in the area of the outer edge of the

Microchip substrate (2) arranged electrical contact (8) is provided which is connected to the front of the

Microchip substrate (2) is in an electrically conductive connection, characterized in that the electrical

Contact (8) is held in contact with the front side of the microchip substrate (2) by a layer (15) lying on its side facing away from the microchip substrate (2), so that the layer (15) is a polymer film that the microchip substrate (2) in a holder (6) is arranged, that the holder (6) has a recess (10) in which the microchip substrate (2) is received, and that the recess (10) has a height which essentially corresponds to the thickness of the microchip substrate ( 2) corresponds.

2. Arrangement according to claim 1, characterized in that the layer (15) resting on the electrical contact (8) is annular.

3. Arrangement according to claim 2, characterized in that the shape of the layer (15) essentially corresponds to the outline shape of the microchip substrate (2).

4. Arrangement according to claim 3, characterized in that the layer (15) is circular.

5. Arrangement according to one of claims 1 to 4, characterized

characterized in that the electrical contact (8) projects beyond the outer edge of the microchip substrate (2).

6. Arrangement according to one of claims 1 to 5, characterized

characterized in that the layer (15) protrudes beyond the outer edge of the microchip substrate (2).

7. Arrangement according to one of claims 1 to 6, characterized

characterized in that the layer (15) can be removed from the microchip substrate (2).

8. Arrangement according to one of claims 1 to 7, characterized

characterized in that the polymer film is covered, in particular coated, with at least one conductor track.

9. Arrangement according to one of claims 1 to 8, characterized

characterized in that the polymer film is connected to the front side of the microchip substrate (2) with the aid of an adhesive, preferably with the aid of an electrically conductive adhesive.

10. Arrangement according to one of claims 1 to 9, characterized

characterized in that the layer is a laminate which, on its side facing the microchip substrate, has a layer which is softened by heating, in particular a layer made of a thermoplastic material.

11. Arrangement according to one of claims 1 to 10, characterized

characterized in that the electrical contact (8) is formed by a ring (16) made of electrically conductive material.

12. The arrangement according to claim 11, characterized in that the inner edge of the ring (16) has projections (18) resting on the front side of the microchip substrate (2).

13. Arrangement according to claim 12, characterized in that the edges and / or the free ends of the projections (18) are bent towards the microchip substrate (2) or have ridges or prongs protruding towards the microchip substrate (2).

14. Arrangement according to one of claims 1 to 13, characterized

characterized in that the electrical contact (8) is formed by a plurality of strips (21) of electrically conductive material distributed over the outer edge of the microchip substrate (2) and that one end (20) each

Strip (21) rests on the front of the microchip substrate (2).

15. The arrangement according to claim 14, characterized in that the strips (21) with respect to the microchip substrate (2) are aligned radially and that the radially inner ends (20) of the strips (21) on the front side of the

Microchip substrate rest.

16. The arrangement according to claim 14 or 15, characterized in that the ends (20) of the strips (21) resting on the microchip substrate (2) are bent towards the microchip substrate (2) or burrs or protruding towards the microchip substrate (2) Have prongs.

17. Arrangement according to one of claims 5 to 16, characterized

marked that the over the outer edge of the

Microchip substrate (2) protruding area of the

electrical contact (8) is in electrically conductive connection with a busbar (9).

18. Arrangement according to one of claims 1 to 17, characterized

characterized in that the layer (15) and the at least one electrical contact (8) with their outside of the

Microchip substrate (2) lying areas on the The bracket (6) and / or the busbar (9) rest,

19. Arrangement according to one of claims 1 to 18, characterized

characterized in that the holder (6) has at least one opening (14) that can be acted upon by negative pressure in the region of the microchip substrate (2) arranged in it.

20. The arrangement according to claim 19, characterized in that the opening (14) which can be acted upon by negative pressure is arranged in the region of the recess (10) of the holder (6).

21. Arrangement according to claim 20, characterized in that the at least one opening (14) with at least one groove (12, 13) which is open towards the recess (10),

communicates.

22. Arrangement according to claim 21, characterized in that two or more than two annular grooves (12) are provided and that the grooves (12) with each other

Connecting grooves (13), which are for example aligned radially to the recess (10), are connected.

23. Arrangement according to one of claims 1 to 22, characterized

characterized in that the holder (6) is designed on both sides to accommodate microchip substrates (2) and in particular has recesses (10) on both sides.