SYSTEM FOR A CHEMICAL AND/OR ELECTROLYTIC SURFACE TREATMENT OF A SUBSTRATE

Abstract

The disclosure relates to a system for a chemical and/or electrolytic surface treatment of a substrate comprises a catholyte chamber, an anolyte chamber, a distribution body, and a catholyte outlet. The distribution body is arranged in the catholyte chamber and the catholyte chamber is separated from the anolyte chamber by means of a membrane, wherein the membrane is tilted relative to the distribution body. The distribution body comprises jet openings for distributing a catholyte onto the substrate to be treated and drain openings for draining the catholyte out of a reaction space between the distribution body and the substrate. The catholyte outlet is arranged at the catholyte chamber in an eccentric position.

Claims

1. A system for a chemical and/or electrolytic surface treatment of a substrate, comprising: a catholyte chamber, an anolyte chamber, a distribution body, and a catholyte outlet, wherein the distribution body is arranged in the catholyte chamber, wherein the catholyte chamber is separated from the anolyte chamber by means of a membrane, wherein the membrane is tilted relative to the distribution body, wherein the distribution body comprises jet openings for distributing a catholyte onto the substrate to be treated and drain openings for draining the catholyte out of a reaction space between the distribution body and the substrate, and wherein the catholyte outlet is arranged at the catholyte chamber in an eccentric position.

2. The system according to claim 1, wherein the catholyte chamber has a lateral side, which extends essentially perpendicular to a longitudinal direction of the distribution body, and wherein the catholyte outlet is arranged in the lateral side of the catholyte chamber.

3. The system according to claim 1, wherein the catholyte chamber, in a cross section, has a wedge shape.

4. The system according to claim 2, wherein the wedge shaped catholyte chamber has, in a cross section, a longer lateral side and a shorter lateral side, and wherein the catholyte outlet is arranged in the longer lateral side of the catholyte chamber.

5. The system according to claim 1, wherein the catholyte outlet is arranged at the catholyte chamber in a non-rotation symmetric position.

6. The system according to claim 1, wherein the catholyte chamber comprises a drain ring arranged around the distribution body for draining the catholyte out of the reaction space between the distribution body and the substrate.

7. The system according to claim 1, wherein the drain openings and/or the drain ring are configured to drain the catholyte essentially perpendicular to a substrate's surface to be treated, and/or wherein the drain ring is configured as an open overflow for catholyte out of the reaction space and/or as a vent for bubbles generated or transported in the reaction space, and in particular, wherein the system comprises a rotating substrate holder.

8. The system according to claim 1, wherein the jet openings are configured to distribute the catholyte essentially perpendicular onto the substrate to be treated.

9. The system according to claim 1, wherein the drain openings extend from a substrate facing surface of the distribution body to a back surface of the distribution body, which is opposite to the substrate facing surface.

10. The system according to claim 1, wherein the jet openings extend from the substrate facing surface of the distribution body only partially into the distribution body and lead to a catholyte inlet arranged at a lateral side of the distribution body .

11. The system according to claim 1, wherein the catholyte chamber comprises a protective gas system to provide a protective gas curtain between the catholyte and the surrounding atmosphere.

12. The system according to claim 1, further comprising a catholyte circulation system for circulating the catholyte in the catholyte chamber and an anolyte circulation system for circulating the anolyte in the anolyte chamber, wherein the catholyte circulation system is separate from the anolyte circulation system, in particular, wherein the catholyte circulation system is configured to circulate the catholyte in such a manner as to promote bubble separation in a catholyte tank and/or the anolyte circulation system is configured to circulate the anolyte in such a manner as to promote bubble separation in an anolyte tank, and/or wherein the system comprises a first bubble separator upstream an/the anolyte storage tank and/or a second bubble separator upstream a/the catholyte storage tank.

13. The system according to claim 1, wherein the membrane is tilted so as to merge and/or remove bubbles generated at the anode, and/or wherein the membrane is permeable for electric current and metallic ions.

14. The system according to claim 1, wherein the anolyte chamber comprises at least one inner anolyte inlet, at least one outer anolyte inlet and at least one anolyte outlet, which are selectable to adjust an anolyte flow to different substrate dimensions, in particular, wherein the anolyte outlet is configured to allow for removal of gas bubbles generated at the anode, in particular, by means of a/the anolyte circulation system.

15. The system according to claim 1, wherein the system has a height in a range of 50 to 350 mm, particularly, wherein the system has a height in a range of 200 mm to 350 mm, particularly 230 mm to 260 mm, or in a range of 50 mm to 200 mm, more particularly 80 mm to 120 mm.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Exemplary embodiments of the disclosure will be described in the following with reference to the accompanying drawing:

[0071] FIG. 1a shows, schematically and exemplarily, a side view of a cross-section of a system for a chemical and/or electrolytic surface treatment of a substrate according to an embodiment;

[0072] FIG. 1b shows schematically and exemplarily, a side view of a cross-section of a system for chemical and/or electrolytic surface treatment of a substrate according to an embodiment;

[0073] FIG. 2 shows, schematically and exemplarily, an enlarged view of part of the system of FIG. 1a or 1b;

[0074] FIGS. 3a to 3c show, schematically, catholyte and anolyte flow through the system of FIG. 1a or 1b;

[0075] FIG. 4 shows, schematically and exemplarily, a side view of a cross-section of a system for a chemical and/or electrolytic surface treatment of a substrate according to an embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

[0076] FIGS. 1a and 1b show, schematically and exemplarily, an embodiment of a system 10 for a chemical and/or electrolytic surface treatment of a substrate 11 according to the disclosure. When the system is in use, the substrate 11 may be held in a substrate holder, which is not shown here for the sake of illustration, and is not part of the system of the present disclosure.

[0077] The system comprises a catholyte chamber 12 for catholyte 13 and an anolyte chamber 14 for anolyte 15. The catholyte chamber 12 is separated from the anolyte chamber 14 by means of a membrane 18, which is tilted relative to the distribution body 16, which is arranged in the catholyte chamber 12. A membrane that is permeable for electric current and metallic ions may be used as the membrane 18, for example.

[0078] It is noted that in the present disclosure the anolyte chamber may have one anolyte zone or may have multiple anolyte zones, e.g., with separated anodes and funnels in between. When the anolyte chamber has multiple anolyte zones, the zones may be configured to be activated independently of each other. For example, there may be an inner zone and an outer zone, and the inner zone may be activated independently from the outer zone, e.g., the inner zone may be activated when the outer zone is deactivated or activated when the outer zone is activated. In other words, the system may be configured for a selective activation of the inner zone and the outer zone, for example such that inner zone and the outer zone may be activated together or independently of each other, based on an automatic and/or user selection. For example, the inner zone may be selectively activated alone or together with the outer zone. There may be multiple inlets and/or outlets, e.g., different inlets for different anolyte zones, particularly configured so as to allow independently activating the anolyte zones.

[0079] In the example illustrated in FIG. 1a, the anolyte chamber 14 is shown as comprising an inner anolyte inlet 14a, an outer anolyte inlet 14b and an anolyte outlet 14c, which are selectable to adjust an anolyte 15 flow to different substrate dimensions. The different anode zones can be filled with pellets, which may for example be Cu-pellets or SnAg-pellets.

[0080] In the present embodiment, the catholyte chamber 12, in a cross section, has a wedge shape, for example. In this embodiment, for example, the wedge shaped catholyte chamber 12 has, in a cross section, a longer lateral side 12a and a shorter lateral side 12b. However, the catholyte chamber 12 may have other cross-sectional shapes.

[0081] The system further comprises a catholyte outlet 17. The catholyte outlet 17 is arranged at the catholyte chamber 12 in an eccentric position 20. More specifically, in the present embodiment, the catholyte outlet 17 is arranged in one of the lateral sides of the catholyte chamber 12, as an example in the longer lateral side 12a of the catholyte chamber 12. The catholyte outlet 17 is also arranged at the catholyte chamber 12 in a non-rotation symmetric position 20. However, other arrangements are conceivable.

[0082] As can be seen from the Figure, the catholyte outlet 17, when the system is arranged for its intended use, may be arranged at a position below the distribution body 16, particularly in a lateral side of the catholyte chamber. In other words, the catholyte outlet 17 may be arranged between the distribution body 16 and the membrane 18, particularly in a lateral side of the catholyte chamber. More specifically, the catholyte outlet 17, when the system is arranged for its intended use, may open into the catholyte chamber at a position below the distribution body 16, or, in other words, the catholyte outlet 17 may open into the catholyte chamber at a position between the distribution body 16 and the membrane 18.

[0083] The catholyte chamber 12 may optionally comprise a protective gas system 12d to provide a protective gas curtain between the catholyte and the surrounding atmosphere. Protecting gas maybe also injected into the anolyte and catholyte storage tank.

[0084] The protective gas system 12d may be configured to provide the protective gas curtain between the catholyte and the surrounding atmosphere. The protective gas system 12d may comprise inlets for the protective gas, for example for nitrogen, and an outlet for the protective gas and/or other gas, e.g., gas created as part of the process.

[0085] As mentioned above, the system further comprises the distribution body 16 arranged in the catholyte chamber 12.

[0086] A reaction space 19 is arranged between the distribution body 16 and the substrate 11.

[0087] The distribution body 16 comprises jet openings 16a for distributing the catholyte 13 onto the substrate 11 to be treated. In particular, the jet openings 16a may be configured to distribute the catholyte 13 essentially perpendicular onto the substrate 11 to be treated. However, directions deviating from the perpendicular direction are conceivable.

[0088] In FIG. 1a, the jet openings 16a are illustrated as extending from the substrate facing surface 16c of the distribution body 16 only partially into the distribution body 16 and lead to a catholyte inlet 16e arranged at a lateral side 16f of the distribution body 16.

[0089] The distribution body further comprises drain openings 16b for draining the catholyte 13 out of the reaction space 19 between the distribution body 16 and the substrate 11.

[0090] In FIG. 1a, the drain openings 16b are shown as extending from a substrate facing surface 16c of the distribution body 16 to a back surface 16d of the distribution body 16, which is opposite to the substrate facing surface 16c. However, other arrangements are conceivable.

[0091] The drain openings 16b may be configured to drain the catholyte 13 essentially perpendicular to a substrate's surface to be treated 11a. However, directions deviating from the perpendicular direction are conceivable.

[0092] The above-mentioned lateral sides 12a and 12b of the catholyte chamber 12 may extend essentially perpendicular to the substrate facing surface 16c.

[0093] A longitudinal direction 21 of the distribution body 16 is indicated in FIG. 1a by a dashed line. In this specific example, the above-mentioned lateral sides 12a and 12b of the catholyte chamber 12 may extend essentially perpendicular to the longitudinal direction 21 of the distribution body 16.

[0094] In FIG. 1a, the system 10 is shown, merely as an example, with a catholyte chamber 12 comprising a drain ring 12c arranged around the distribution body 16 for draining the catholyte 13 out of the reaction space 19 between the distribution body 16 and the substrate 11. The drain ring 12c is configured to drain the catholyte 13 essentially perpendicular to a substrate's surface to be treated 11a.

[0095] Optionally, the system 10 may comprise a catholyte circulation system 24 for circulating the catholyte 13 in the catholyte chamber 12 and an anolyte circulation system 25 for circulating the anolyte 15 in the anolyte chamber 14. The circulation systems, as illustrated in FIG. 1a may comprise a catholyte tank 24a and an anolyte tank 25a and (not illustrated) pumps or other transport devices. The arrows 24b represent, merely schematically, a flow direction of the catholyte and the arrow 25b represents a flow direction of the anolyte. The catholyte circulation system 24 is separate from the anolyte circulation system 25.

[0096] In this context, it is noted that in the Figures an inlet for the anolyte and an inlet for the catholyte, due to the 2D representation of the 3D system, overlap. That is, an inlet for the anolyte (flow direction indicated by arrow 25b) is shown as being arranged in front of an inlet for the catholyte (flow direction indicated by arrow 24b), in the viewing direction.

[0097] FIG. 1b shows a system like the one described above in the context of FIG. 1a. The presence and movements of bubbles 27 are illustrated in said FIG. 1b. Moreover, it can be seen that the catholyte and anolyte do not fill the tanks completely, so there is a liquid level 28 in the respective tank. As mentioned above, protecting gas maybe also injected into the anolyte and catholyte tank. In this example injection of N.sub.2 is indicated by arrows. Bubbles are let out of the tanks through a respective vent. Exemplary pumps 29 for pumping the catholyte and anolyte and inline gas extractors 30, which serve to remove bubbles, are also shown in FIG. 1b.

[0098] FIG. 2 shows, schematically and exemplarily, an enlarged view of part of the system of FIG. 1a or 1b. In particular, FIG. 2 serves to allow for an enlarged view of the part of the system including the distribution body 16 and the membrane 18. A membrane carrier plate 18a is indicated, as well. It is noted that the membrane may be supported in both directions, wherein the catholyte chamber 12 includes a support plate, which, in intended operation, is an upper support.

[0099] FIGS. 3a to 3c show, schematically, catholyte and anolyte flow through a system according to the present disclosure, in particular, for illustrative purposes, through the system of FIG. 1a or 1b. As described above, the anolyte chamber 14 may comprise an inner anolyte inlet 14a, an outer anolyte inlet 14b and an anolyte outlet 14c, which are selectable to adjust an anolyte 15 flow to different substrate dimensions. In the case of FIG. 3a, the inner anolyte inlet 14a is selected, whereas in FIG. 3b the inner and outer anolyte inlet are selected together.

[0100] It is noted that, so as to avoid a cluttered view, the catholyte flow is only shown from the point where it leaves the reaction space in FIGS. 3a and 3b. FIG. 3c shows the flow of the catholyte into the distribution body and through the distribution body.

[0101] It is noted that the system of FIGS. 1 to 3 also includes an anode and a cathode, omitted to avoid cluttering.

[0102] It is noted that in general the size of the cathode may, in preferred embodiments, be selected so as to match the anode size and wafer size.

[0103] FIG. 4 shows, schematically and exemplarily, a side view of a cross-section of a system for a chemical and/or electrolytic surface treatment of a substrate according to an embodiment. The system is configured similarly to the one shown in FIGS. 1 to 3c. However, the height 26 is smaller than in said Figures. This serves to illustrate that a particularly compact build is possible with the claimed system 10.

[0104] As an example, the system 10 may have a height 26 in a range of 50 to 80 mm, preferably 60 to 70 mm. However, other dimensions are conceivable.

[0105] As an example, the system 10 may have a height 26 in a range of 50 mm to 350 mm. In one embodiment, e.g. where pellets are used (e.g. Cu, SnAg), the height may preferably be in a range of 200 mm to 350 mm, more preferable 230 mm to 260 mm. In another example, where inert anodes are used, the height may preferably be in a range of 50 mm to 200 mm, more preferable 80 mm to 120 mm.

[0106] The height may, for example, refer to a combined height of the anolyte chamber, the catholyte chamber, and the reaction space.

[0107] While the disclosure has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. The disclosure is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing a claimed disclosure, from a study of the drawings, the disclosure, and the dependent claims.

[0108] In the claims, the word comprising does not exclude other elements or steps, and the indefinite article a or an does not exclude a plurality. The mere fact that certain measures are re-cited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.