DISTRIBUTION SYSTEM FOR A PROCESS FLUID FOR CHEMICAL AND/OR ELECTROLYTIC SURFACE TREATMENT OF A ROTATABLE SUBSTRATE

Abstract

The disclosure relates to a distribution system for a process fluid for chemical and/or electrolytic surface treatment of a rotatable substrate, an electrochemical deposition system for a chemical and/or electrolytic surface treatment of a substrate and a method for a chemical and/or electrolytic surface treatment of a substrate in a process fluid. The distribution system comprises a distribution body. The distribution body comprises a plurality of openings for the process fluid. The openings are arranged in a spiral-shaped pattern on a surface of the distribution body.

Claims

1. A distribution system suitable for a process fluid for chemical and/or electrolytic surface treatment of a rotatable substrate, wherein the distribution system comprises a distribution body, wherein the distribution body comprises a plurality of openings, wherein some of the openings are configured to provide the process fluid flow and other openings are configured to provide a current density distribution, wherein the openings for providing the process fluid flow are arranged in a spiral-shaped pattern on a surface of the distribution body, and wherein the openings for providing the current density distribution are arranged on the surface of the distribution body independently of second portion of the openings for providing the process fluid flow.

2. The distribution system according to claim 1, wherein, in case the substrate is rotating relative to the distribution body, the spiral-shaped pattern enables several areas of the substrate to be exposed to similar process fluid flows and/or similar current density distributions, respectively.

3. The distribution system according to claim 1, wherein the spiral-shaped pattern is formed in that the openings are arranged along an imaginary curve, which winds around a starting point (C) on the distribution body at a continuously increasing distance from the starting point.

4. The distribution system according to claim 3, wherein the starting point (C) is a geometric centre (C) of the distribution body.

5. The distribution system according to claim 3, wherein the starting point (C) is outside a geometric centre (C) of the distribution body.

6. The distribution system according to claim 1, wherein the spiral-shaped pattern is based on an Archimedean spiral.

7. The distribution system according to claim 1, wherein the spiral-shaped pattern is based on a logarithmic spiral.

8. The distribution system according to claim 1, wherein the spiral-shaped pattern is based on a parabolic spiral.

9. The distribution system according to claim 1, wherein the spiral-shaped pattern is based on a square root spiral.

10. The distribution system according to claim 1, wherein the spiral-shaped pattern is based on a hyperbolic spiral.

11. The distribution system according to claim 1, wherein the spiral-shaped pattern is based on a Fibonacci spiral.

12. The distribution system according to claim 1, wherein the spiral-shaped pattern is a combination of two or more spirals.

13. An electrochemical deposition system for a chemical and/or electrolytic surface treatment of a substrate, comprising: a distribution system according to one of the preceding claims, and a substrate rotation system, wherein the substrate rotation system is configured to rotate a substrate relative to a distribution body of the distribution system.

14. A method for a chemical and/or electrolytic surface treatment of a substrate in a process fluid, comprising: providing a distribution system comprising a distribution body with a plurality of openings, rotating the substrate relative to the distribution system, and providing the process fluid flow via some of the openings and providing a current density distribution via other openings, wherein the openings for providing the process fluid flow are arranged in a spiral-shaped pattern on a surface of the distribution body, and wherein the openings for providing the current density distribution are arranged on the surface of the distribution body independently of the openings for providing the process fluid flow.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Exemplary embodiments of the disclosure will be described in the following with reference to the accompanying drawing:

[0068] FIG. 1 shows schematically and exemplarily an embodiment of a distribution body for a process fluid for chemical and/or electrolytic surface treatment of a rotatable substrate.

[0069] FIG. 2 shows schematically and exemplarily an Archimedean spiral.

[0070] FIG. 3 shows schematically and exemplarily a logarithmic spiral.

[0071] FIG. 4 shows a graph depicting a distribution of a “drain hole ratio” as a function of a radius of a substrate.

[0072] FIG. 5A and FIG. 5B show schematically and exemplarily an embodiment of a distribution body for a process fluid for chemical and/or electrolytic surface treatment of a rotatable substrate.

DETAILED DESCRIPTION OF EMBODIMENTS

[0073] FIG. 1 shows schematically and exemplarily an embodiment of a distribution body 1 for a process fluid for chemical and/or electrolytic surface treatment of a rotatable substrate (not shown). The distribution body 1 is part of a distribution system 10 for a process fluid for chemical and/or electrolytic surface treatment of a rotatable substrate. The distribution body 1 may be arranged between an electrode (not shown) of the distribution system 10 and the substrate. The distribution body 1 may be a high-speed plate (HSP). The substrate may rotate relative to the distribution body 1.

[0074] The distribution body 1 comprises a plurality of openings 2 for the process fluid. The process fluid is an electrolyte and may transport the current density. The openings 2 face the substrate and allow the process fluid to flow from the electrode to the substrate. The openings 2 are arranged in a spiral-shaped pattern on a surface of the distribution body 1. The openings 2 direct the process fluid flow and/or a current density distribution to the substrate, and in case the substrate is rotating relative to the distribution body 1, the spiral-shaped pattern enables that several areas of the substrate are exposed to similar process fluid flows and/or similar current density distributions, respectively. The electrolyte and the current density of the process fluid can be discharged from separate features and sections of the distribution body 1. For this, the distribution body 1 comprises at least one jet for discharging electrolyte and at least one distribution element for the current density distribution.

[0075] The distribution system 10 is part of an electrochemical deposition system 20 for a chemical and/or electrolytic surface treatment of a substrate. The electrochemical deposition system 20 comprises the distribution system 10 and a substrate rotation system (not shown). The substrate rotation system is configured to rotate a substrate relative to a distribution body 1 of the distribution system 10. By rotating the substrate during application of the process fluid, an even distribution of the process fluid is ensured, therefore forming a homogenous coating on the substrate surface.

[0076] The openings 2 are arranged in a spiral-shaped pattern on the distribution body 1, such as in an Archimedean spiral S1 pattern, as shown in FIG. 2, or a logarithmic spiral S2 pattern, as shown in FIG. 3. The spiral arrangement of the openings 2 follows mathematical directives for a spiral where locations for the openings 2 are determined corresponding to location points along lines described by a spiral moving continuously outward from a fixed starting point C.

[0077] With the spiral-shaped pattern of the openings 2, each unit area of the substrate is exposed to the same amount of incoming electrolyte flow and current density averaged over the process time. A uniform electroplating without rotational artefacts is ensured when the substrate is rotating.

[0078] The spiral-shaped pattern is formed in that the openings 2 are arranged along an imaginary curve, which winds around a starting point C on the distribution body 1 at a continuously increasing distance from the starting point C. The starting point C of the spiral-shaped pattern is the geometric center C of the distribution body 1 in FIG. 1. A distance between adjacent openings 2 along an imaginary spiral curve is constant from the starting point C of the spiral to more remote portions of the distribution body 1. As shown in FIG. 1, the openings 2 have an equal size throughout the distribution body 1 and can have any cross-section, e.g. round, square or tri/multi-angular

[0079] FIG. 2 shows schematically and exemplarily an Archimedean spiral S1. The distance between neighboring arcs A is equal between each consecutive spiral loops or arcs A. The Archimedean spiral S1 is used to define the locations of the openings 2 on a surface 1b of the distribution body 1.

[0080] FIG. 3 shows schematically and exemplarily a logarithmic spiral S2, in which the distances between consecutive arcs A are increasing starting from the center to the outer portions. The logarithmic spiral S2 can also be used to define the locations of the openings 2 on the surface 1b of the distribution body 1.

[0081] FIG. 4 shows a graph depicting a distribution of a “drain hole ratio” (DHR) as a function of a radius (r) of a rotating e.g. 300 mm wafer with an arrangement of electrolyte and current distribution openings 2. The drain hole ratio describes a percentage of an open area (area of the openings 2) relative to a closed area (area without openings 2) along a specific radius of a distribution body 1 from a starting point C of a spiral to an outer edge of the distribution body 1. The “X” symbols in FIG. 4 depict the drain hole actual values of the distribution body 1 and the “O” symbols depict averaged values over 10 neighbouring drain holes.

[0082] In principle it was found, that the more uniform the drain hole ratio distribution over the radius from the starting point to the outer edge, the higher the uniformity of the material deposition on the substrate, especially, when the substrate is in rotational movement relative to the distribution body 1. As it can be seen from FIG. 4, the distribution body 1 allows an excellent drain hole uniformity over the radius, resulting in a significant improvement of the deposition uniformity distribution over the substrate.

[0083] FIG. 5A and FIG. 5B show an arrangement of the openings 2, which are divided into a first portion 21 (jet holes) and a second portion 22 (drain holes). Each drain hole 22 is surround by three jet holes 21, wherein the drain holes 22 are arranged in a spiral-shaped pattern on the surface 1b of the distribution body 1. The drain holes 22 may be formed as through-holes extending the through the distribution body 1 and configured to provide a current density distribution to the substrate and to enable a backflow of the process fluid from the substrate. The jet holes 21 may be formed only in one direction on the distribution body 1, preferably in the direction of the substrate, to provide the process fluid to the substrate.

[0084] It has to be noted that embodiments of the disclosure are described with reference to different subject matters. In particular, some embodiments are described with reference to method type claims whereas other embodiments are described with reference to the device type claims. However, a person skilled in the art will gather from the above and the following description that, unless otherwise notified, in addition to any combination of features belonging to one type of subject matter also any combination between features relating to different subject matters is considered to be disclosed with this application. However, all features can be combined providing synergetic effects that are more than the simple summation of the features.

[0085] 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.

[0086] 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. A single processor or other unit may fulfil the functions of several items re-cited in the claims. 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.

EMBODIMENTS

[0087] 1. A distribution system (10) for a process fluid for chemical and/or electrolytic surface treatment of a rotatable substrate, [0088] wherein the distribution system (10) comprises a distribution body (1), [0089] wherein the distribution body (1) comprises a plurality of openings (2) for the process fluid, and [0090] wherein the openings (2) are arranged in a spiral-shaped pattern on a surface (1b) of the distribution body (1). [0091] 2. Distribution system (10) according to embodiment 1, wherein the openings (2) are configured to direct the process fluid flow and/or a current density distribution to the substrate, and wherein, in case the substrate is rotating relative to the distribution body (1), the spiral-shaped pattern enables several areas of the substrate to be exposed to similar process fluid flows and/or similar current density distributions, respectively. [0092] 3 Distribution system (10) according to one of the preceding embodiments, wherein the spiral-shaped pattern is formed in that the openings (2) are arranged along an imaginary curve, which winds around a starting point (C) on the distribution body (1) at a continuously increasing distance from the starting point. [0093] 4. Distribution system (10) according to embodiment 3, wherein the starting point (C) is a geometric centre (C) of the distribution body (1). [0094] 5. Distribution system (10) according to embodiment 3, wherein the starting point (C) is outside a geometric centre (C) of the distribution body (1). [0095] 6. Distribution system (10) according to one of the embodiments 1 to 5, wherein the spiral-shaped pattern is based on an Archimedean spiral (S1). [0096] 7 Distribution system (10) according to one of the embodiments 1 to 5, wherein the spiral-shaped pattern is based on a logarithmic spiral (S2). [0097] 8. Distribution system (10) according to one of the embodiments 1 to 5, wherein the spiral-shaped pattern is based on a parabolic spiral. [0098] 9. Distribution system (10) according to one of the embodiments 1 to 5, wherein the spiral-shaped pattern is based on a square root spiral. [0099] 10. Distribution system (10) according to one of the embodiments 1 to 5, wherein the spiral-shaped pattern is based on a hyperbolic spiral. [0100] 11. Distribution system (10) according to one of the embodiments 1 to 5, wherein the spiral-shaped pattern is based on a Fibonacci spiral. [0101] 12. Distribution system (10) according to one of the preceding embodiments, wherein the spiral-shaped pattern is a combination of two or more spirals. [0102] 13. An electrochemical deposition system (20) for a chemical and/or electrolytic surface treatment of a substrate, comprising: [0103] a distribution system (10) according to one of the preceding embodiments, and [0104] a substrate rotation system, [0105] wherein the substrate rotation system is configured to rotate a substrate relative to a distribution body (1) of the distribution system (10). [0106] 14. A method for a chemical and/or electrolytic surface treatment of a substrate in a process fluid, comprising: [0107] providing a distribution system (10) comprising a distribution body (1) with a plurality of openings (2) for the process fluid, wherein the openings (2) are arranged in a spiral-shaped pattern on a surface of the distribution body (1), [0108] rotating the substrate relative to the distribution system (10), and [0109] chemically and/or electrolytically treating a surface of the substrate.