Edge removal for through-resist plating

Abstract

The electroplating cup assembly includes a cup bottom, a lip seal, and an electrical contact structure. The cup bottom defines at least partially an opening configured to allow exposure of a wafer positioned within the cup assembly to the electroplating solution. The lip seal is located on the cup bottom and includes a sealing structure extending upward along the inner edge of the lip seal to a peak configured adjacent to the wafer's sacrificial layer and contacting the wafer's seed layer. The electrical contact structure is located on a portion of the seal. The electrical contact structure is configured to be coupled to the wafer's seed layer.

Description

Background Technology

[0001] Electroplating is commonly used in integrated circuit fabrication processes to form electrically conductive structures. For example, in the copper damascene process, electroplating is used to form copper lines and vias within channels previously etched with a dielectric layer. In this process, a copper seed layer is first deposited into the channels and on the substrate surface via physical vapor deposition. Subsequently, electroplating is used to deposit a thicker copper layer over the seed layer so that the channels are completely filled. The excess copper is then removed by chemical mechanical polishing to form individual copper features.

[0002] Current electroplating systems may be classified into "open contact" and "closed contact" types. Open contact plating systems are systems in which wafer contacts that transmit current to the seed layer during plating are exposed to the plating solution. Similarly, closed contact plating systems are systems in which the contacts are not exposed to the plating solution.

[0003] When manufacturing integrated circuits, it is generally desirable to utilize as much wafer surface as possible for device fabrication to increase the number of devices per wafer. However, electroplating systems typically utilize electrical contacts and other structures that come into contact with the wafer during deposition. Consequently, a limited amount of surface area may be plated. For example, in open-contact plating systems, electrodes are plated onto the substrate surface during the process because they are exposed to the plating solution. Removal of the electrodes exposes unplated regions where the electrodes come into contact with the substrate. Additionally, the removal of contacts may cause damage to the copper layer in the vicinity of the electrodes. For instance, the outer periphery of the wafer, extending more than 2 mm, may become unsuitable for integrated circuit fabrication.

[0004] Existing RDL technology has a nominal seed thickness (1000 to 3000 ) is used. These thicknesses are susceptible to CD loss, line roughness, and undercuts during long aggressive seed etching processes. To reduce etching time, 1000 (e.g., 50, 100, 200, 400 Attempts to enable thin-seed plating below ) have focused primarily on anode tuning (size, shape, number) to control current distribution. These changes are located far from the wafer surface and tend to cause global correction. As such, they cannot achieve the local correction required for terminal effects and often result in wavy, non-uniform current (and subsequent plating thickness) profiles.

[0005] FIG. 1 illustrates a cross-sectional view of an electroplating cup assembly (100) according to the prior art. The lip seal of the electroplating system is coupled to the perimeter of the wafer and adjacent to the outermost yielding feature. Electroplating using the electroplating cup assembly (100) typically results in a plating thickness greater at the wafer edge on the surface of the wafer due to the "end effect." The end effect occurs when the seed resistance dominates the plating bath equivalent circuit and results in significant electrodeposition at the wafer edge on the surface of the wafer.

[0006] This application claims priority to U.S. Provisional Patent Application No. 62 / 941,519 filed on November 27, 2019, the entirety of which is incorporated herein by reference. Brief explanation of the drawing

[0007] To facilitate the identification of any specific element or act, the top digit or digits of the reference number refer to the drawing number where the element was first introduced. FIG. 1 illustrates a cross-sectional view of an electroplating cup assembly (100) according to the prior art. FIG. 2 illustrates a cross-sectional view of an electroplating cup assembly (200) according to one embodiment. FIG. 3 illustrates a cross-sectional view of an electroplating cup assembly (300) according to one embodiment. FIG. 4 illustrates a cross-sectional view of an electroplating cup assembly (400) according to one embodiment. FIG. 5 illustrates a wafer (500) for use with an electroplating cup assembly (200) according to one embodiment. FIG. 6 illustrates a wafer (600) for use with an electroplating cup assembly (200) according to one embodiment. FIG. 7 illustrates a wafer (700) for use with an electroplating cup assembly (200) according to one embodiment. FIG. 8 illustrates a wafer (800) for use with an electroplating cup assembly (200) according to one embodiment. FIG. 9 illustrates a wafer (900) for use with an electroplating cup assembly (200) according to one embodiment. Specific details for implementing the invention

[0008] The following description describes systems, methods, techniques, and instruction sequences that illustrate exemplary embodiments of the subject matter of the present claim. In the following description, for the purposes of explanation, a number of specific details are presented to provide an understanding of various embodiments of the subject matter of the present invention. However, it will be obvious to those skilled in the art that embodiments of the subject matter of the present claim may be practiced with or without some or all of these specific details. Examples are merely representative of possible variations. Unless otherwise expressly stated, structures (structural components such as modules, e.g.) may be optionally combined or subdivided, and operations (e.g., procedures, algorithms, or other functions) may be varied in order, combined, or subdivided.

[0009] The term "wafer" is used herein to refer to a semiconductor substrate. Examples of wafers include slices of crystalline silicon.

[0010] The term "electroplating solution" is used herein to refer to an electrolyte solution used for plating metal.

[0011] The term "lip seal" is used herein to refer to a radial shaft seal.

[0012] The term “edge-bevel removal (EBR) tool” is used herein to refer to a tool / system used to remove the bevel edge of a wafer. Wafers have two typical edge types: a beveled shape or a rounded bullet shape. The edges of the bevel types are referred to as the bevel region. In one example, EBR is a process that uses sulfuric acid and hydrogen peroxide to remove the edge and back-side metal layer.

[0013] Fine-line redistribution layers (RDLs), a component of the advanced packaging scheme "High Density Fan-Out" (HDFO), are gaining attention as packages move toward smaller and thinner footprints. In particular, there are several issues associated with fine-line RDLs during the seed etching removal step in the semi-additive process (SAP). These include loss of critical dimension (CD), namely line shrinkage, sidewall roughness evolution, and undercuts, as the copper etchant attacks both the underlying seed and the lines themselves. A possible route to address these challenges is to reduce the thickness of the underlying copper seed on which the lines are plated. Thinner seeds require less etching time and allow for the use of less aggressive seed etching chemicals.

[0014] However, thin-seed plating has inherent challenges, primarily a phenomenon known as the "terminal effect." The terminal effect occurs when a potential drop across a thin metal seed (which is more resistant than thick metal seeds) causes thicker plating near the wafer edge (at contact terminals) than at the center of the wafer.

[0015] Channeled Ionic Resistive Plates (CIRPs) (also known as HRVAs or High Resistance Virtual Anodes) help mitigate edge effects, but this alone is not sufficient for ultra-thin seeds. The system described herein addresses these challenges. This application describes a thin-seed plating process comprising coupling a CIRP optimized with a novel cup + lip seal design and an anode shield during the electroplating process. After plating, an Edge Bevel Removal (EBR) process is performed to remove the sacrificially plated ring. While traditional cups and lip seals are designed to cover the exposed copper seed at the periphery of the wafer to prevent corrosion and plating, one embodiment intentionally exposes a portion of the seed. When this area is exposed, copper can be plated in an annular ring shape at the wafer edge. Stealing current from features very close to this ring reduces the plated thickness. This sacrificial ring can compensate for and correct end effects.

[0016] The present application may also include a post-plating step in which a sacrificial ring of plated copper can be removed. Electrochemical deposition tools such as SABRE and SABRE3D (of Lam Research Inc.) may be equipped with an optional edge-bevel removal (EBR) module to remove Cu deposited on the bevel area of ​​the wafer (since damage, if left untreated, can affect downstream processing). Wafer-level packaging (WLP) typically does not use EBR (used by Damascene and TSVs), but the system described herein may repurpose this module for the removal of the sacrificial copper ring. EBR time, chemicals, and edge exclusion size may be optimized for this process. Downstream processes (e.g., wafer dicing) may be compromised without removing this thick sacrificial plated copper ring.

[0017] In a first embodiment aimed at thin-seed plating of Cu for RDL applications, the system comprises a) specifically all thin-seeds (1000) that are not RDL b) through-resist Cu plating applications, and b) nominal seed thickness (1000) with large pattern exclusion to 3000 It is applicable to ). Large pattern exclusion may be defined herein as a region greater than 0.5 mm in width at the edge of the wafer where photoresist is applied but not patterned. The unpatterned photoresist will not be plated, and therefore patterned regions adjacent to large non-patterned regions tend to be plated with abrupt thickness spikes and thus an edge-uptick is formed.

[0018] In the second embodiment, instead of copper, the process of sacrificial plating and removal can be extended to any metal (Ni, SnAg, Sn, Co). The EBR process can be modified from piranha etching (used for Cu etching in the first embodiment) to nitrogen etching or other chemical etching tailored to the metal to be etched.

[0019] In one exemplary embodiment, an electroplating cup assembly is described. The electroplating cup assembly comprises a cup bottom (having an opening) and a seal disposed on the cup bottom around the opening. The seal comprises a wafer-contact peak located substantially on the inner edge of the seal. The electroplating cup assembly also comprises an electrical contact structure disposed on a portion of the seal.

[0020] In one exemplary embodiment, the electroplating cup assembly comprises: a cup bottom portion that at least partially defines an opening configured to allow exposure of a wafer positioned within the electroplating cup assembly to an electroplating solution; and a lip seal coupled to the cup bottom portion. The lip seal comprises a sealing structure extending upward along the inner edge of the lip seal to a peak configured to contact a seed layer of the wafer and a sacrificial layer of the wafer; and an electrical contact structure forming a seal together with the lip seal, wherein the electrical contact structure is configured to be coupled to the seed layer at the periphery of the wafer.

[0021] In another exemplary embodiment, a method for electroplating a wafer is described. The method comprises: a wafer placement step of placing a wafer on an electroplating cup assembly that exposes the surface of the wafer to an electroplating solution, wherein the surface includes a sacrificial layer at the perimeter of the wafer; a step of electroplating the exposed surface of the wafer; and a step of removing the plated sacrificial layer of the wafer after electroplating the exposed surface of the wafer.

[0022] In another exemplary embodiment, a system for electroplating a wafer is described. The system comprises: a wafer comprising a seed layer and a sacrificial layer, wherein the sacrificial layer is disposed along the periphery of the wafer on the seed layer; and an electroplating cup assembly configured to support the wafer. The electroplating cup assembly comprises: a bottom portion of the cup that at least partially defines an opening configured to allow exposure of the wafer positioned within the electroplating cup assembly to an electroplating solution; a lip seal coupled to the bottom portion of the cup, wherein the lip seal comprises a sealing structure extending upward along the inner edge of the lip seal to a peak configured to contact the seed layer of the wafer and the sacrificial layer of the wafer; and an electrical contact structure forming a seal together with the lip seal, wherein the electrical contact structure is configured to be coupled to the seed layer at the periphery of the wafer.

[0023] FIG. 2 illustrates a cross-sectional view of an electroplating cup assembly (200) according to one embodiment. The electroplating cup assembly (200) comprises a wafer (202), a seed layer (e.g., a copper seed (204)), a photoresist (206), an outermost yield feature (208), a sacrificial layer (210) (e.g., a sacrificial EP film), an electrical contact structure (212), a cup bottom (214), and a lip seal (216). By intentionally exposing a portion of the seed layer at the periphery of the wafer to plate a sacrificial annular region / ring of copper (e.g., a sacrificial layer (210)), current can be thieved from features very close to the wafer edge (e.g., within 5 nm to 10 nm) and reduce the plated thickness. This sacrificial ring compensates for and corrects the end effect.

[0024] The bottom portion of the cup (214) may at least partially define an opening configured to allow exposure to the electroplating solution of a portion of the surface of a wafer (202) positioned within the electroplating cup assembly. For example, the exposed portion of the wafer (202) may include a sacrificial layer (210), an outermost yield feature (208), and a photoresist (206). The exposed portion of the wafer (202) is exposed to the electroplating solution.

[0025] The lip seal (216) is coupled to the bottom portion of the cup (214). The lip seal (216) includes a sealing structure extending upward along the inner edge of the lip seal (216) to a peak configured to contact the copper seed (204) of the wafer (202). The sealing structure is adjacent to the sacrificial layer (210). For example, the sealing structure contacts the vertical surface of the sacrificial layer (210) of the wafer (202).

[0026] The electrical contact structure (212) contacts the copper seed (204) at the periphery of the wafer (202) and forms a seal together with the lip seal (216). For example, the surface area protected by the seal (e.g., the edges of the wafer (202) and the back of the wafer (202)) is not exposed to the electroplating solution.

[0027] FIG. 3 illustrates a cross-sectional view of an electroplating cup assembly (300) according to one embodiment. An electrical contact structure (212) comprises a continuous outer ring positioned below the bus ring (302) and in contact with the bus ring (302) to allow for a uniform distribution of current from the bus ring (302). Additionally, the contact structure comprises a plurality of tabs extending upward from the outer ring of the contact structure into a groove (304) formed within the bus ring (302). The tabs make contact with the inner edge of the groove (304). The tabs are configured to center the electrical contact structure (212) in the correct position relative to the lip seal (216) and the bottom of the cup (214) so ​​as to ensure that all individual contacts (described below) on the electrical contact structure (212) contact the plating seed layer on the wafer (202) positioned within the bottom of the cup (214). Additionally, this feature also helps prevent all contacts from sliding past the lip seal (216) when the wafer is clamped into the electroplating cup assembly (300). The bus ring (302) may include a groove (304) that partially or completely extends around the bus ring (302), or may include two or more individual grooves each accommodating one or more tabs.

[0028] The electrical contact structure (212) includes a plurality of contacts extending from the outer ring toward the center of the electrical contact structure (212). Each contact includes a downwardly extending portion spaced apart from the lip seal (216), and an upwardly turned-up portion (306) configured to make contact with a wafer (202) positioned within the cup assembly. In this way, each contact acts as a leaf spring pushed against the surface of the wafer within the cup with a slight spring force to ensure good contact between the contacts and the wafer. This causes the contacts to make good electrical contact with the wafer on the bevel or wafer surface. Therefore, this feature accommodates normal variations in the bevel position.

[0029] FIG. 4 illustrates a cross-sectional view of an electroplating cup assembly (400) according to one embodiment. An electrical contact structure (212) comprises a continuous outer ring positioned below the bus ring (302) and in contact with the bus ring (302) to allow for a uniform distribution of current from the bus ring (302). Additionally, the contact structure comprises a plurality of tabs extending upward from the outer ring of the contact structure into a groove (304) formed within the bus ring (302). The tabs make contact with the inner edge of the groove (304). The tabs are configured to center the electrical contact structure (212) in the correct position relative to the lip seal (216) and the bottom of the cup (214) so ​​as to ensure that all individual contacts (described below) on the electrical contact structure (212) contact the plating seed layer on the wafer (202) positioned within the bottom of the cup (214). Additionally, this feature also helps prevent all contacts from sliding past the lip seal (216) when the wafer is clamped into the electroplating cup assembly (300). The bus ring (302) may include a groove (304) that partially or completely extends around the bus ring (302), or may include two or more individual grooves each accommodating one or more tabs.

[0030] The electrical contact structure (212) includes a plurality of contacts extending from the outer ring toward the center of the electrical contact structure (212). Each contact includes a downwardly extending portion spaced apart from the lip seal (216), and an upwardly turned-up portion (306) configured to make contact with a wafer (202) positioned within the cup assembly. In this way, each contact acts as a leaf spring pushed against the surface of the wafer within the cup with a slight spring force to ensure good contact between the contacts and the wafer. This causes the contacts to make good electrical contact with the wafer on the bevel or wafer surface. Therefore, this feature accommodates normal variations in the bevel position.

[0031] FIG. 5 illustrates a wafer (500) for use with an electroplating cup assembly (200) according to one embodiment. The wafer (500) comprises a PR edge exclusion (502), a patterned photoresist (504), an unpatterned photoresist (506), and an exposed copper seed region (508).

[0032] In the first embodiment, the system described herein aims for thin-seed plating of Cu for RDL applications as follows: (1) specifically all thin-seed plating (1000) that is not RDL (less than) through-resist Cu plating application, and (2) nominal seed thickness (1000) with large pattern exclusion to 3000 ) (Large pattern exclusion is defined herein as a region greater than 0.5 mm in width at the edge of the wafer where photoresist is applied but not patterned. The unpatterned photoresist will not be plated, and therefore patterned regions adjacent to the large non-patterned regions tend to be plated with abrupt thickness spikes, thus forming an edge-uptick).

[0033] In the second embodiment, the present application processes a sacrificial plating and removes any metal (Ni, SnAg, Sn, Co). The EBR process is modified from piranha etching (used for Cu etching in the first embodiment) to nitrogen etching or other chemical etching tailored to the metal to be etched.

[0034] FIG. 6 illustrates a wafer (600) for use with an electroplating cup assembly (200) according to one embodiment. The wafer (600) comprises a pattern edge exclusion (602), a patterned photoresist region (604), an unpatterned photoresist region (606), and an exposed copper seed region (608). The wafer (600) does not include a PR edge exclusion region (as illustrated in FIG. 5).

[0035] FIG. 7 illustrates a wafer (700) for use with an electroplating cup assembly (200) according to one embodiment. The wafer (700) includes a seal (702), a patterned photoresist region (704), an unpatterned photoresist region (706), and a sacrificial layer region (708).

[0036] In this exemplary embodiment, the seal (702) is formed together with the contact of the lip seal (216). The seal (702) forms a substantially concentric seal in which the sacrificial layer region (708) is plated around the entire periphery of the PR edge exclusion zone (e.g., PR edge exclusion (502)).

[0037] FIG. 8 illustrates a wafer (800) for use with an electroplating cup assembly (200) according to one embodiment. The wafer (800) comprises a seal (802), a patterned photoresist layer (804), an unpatterned photoresist region (806), and a sacrificial layer region (808).

[0038] In this exemplary embodiment, the seal (802) is formed together with the contact of the lip seal (216). The seal (802) forms a substantially concentric seal in which the sacrificial layer region (808) is plated around the entire circumference of the PR edge exclusion zone (e.g., PR edge exclusion (502)).

[0039] In addition, the seal (802) is designed to increase the sacrificial plating area in desirable azimuthal regions. For example, the azimuthal regions include larger patterned edge exclusion zones: "missing die" regions.

[0040] FIG. 9 illustrates a wafer (900) for use with an electroplating cup assembly (200) according to one embodiment. The wafer (900) includes a seal (902), a sacrificial layer region (908), a patterned photoresist region (904), and an unpatterned photoresist region (906).

[0041] In this exemplary embodiment, the seal (902) is formed together with the contact of the lip seal (216). The seal (902) forms a substantially concentric seal in which the sacrificial layer region (908) is plated around the entire circumference of the PR edge exclusion zone (e.g., PR edge exclusion (502)).

[0042] In addition, the seal (902) is designed to increase the sacrificial plating area in desirable azimuth zones. For example, the seal (902) is placed just outside the zone adjacent to the "missing die" zone where only sacrificial copper is plated.

[0043] The above description includes exemplary examples, devices, systems, and methods for implementing the disclosed subject of the claim. In the description, for the purposes of explanation, a number of specific details are provided to provide an understanding of various embodiments of the disclosed subject of the claim. However, it will be obvious to those skilled in the art that various embodiments of the claim may be practiced without these specific details. Furthermore, known structures, materials, and techniques are not depicted in detail so as not to obscure the various illustrated embodiments.

[0044] As used herein, the term "or" may be interpreted in an inclusive or exclusive sense. Furthermore, other embodiments will be understood by those skilled in the art upon reading and understanding the provided disclosures. Additionally, upon reading and understanding the provided disclosures, those skilled in the art will readily understand that various combinations of techniques and examples provided herein may all be applied in various combinations.

[0045] Although various embodiments are discussed separately, these separate embodiments are not intended to be regarded as independent techniques or designs. As indicated above, each of the various parts may be interrelated and each may be used separately or in combination with other particulate matter sensor calibration system embodiments discussed herein.

[0046] Consequently, many modifications and variations may be made, as will be obvious to those skilled in the art by reading and understanding the disclosure provided herein. In addition to those listed herein, methods and devices functionally equivalent within the scope of this disclosure will be obvious to those skilled in the art from the foregoing descriptions. Parts and features of some embodiments may be included in or substituted for parts and features of other embodiments. Such modifications and variations are intended to be within the scope of the appended claims. Therefore, this disclosure is limited only by the terms of the appended claims, along with the full scope of equivalents entitled by such claims. It should also be understood that the terms used herein are for the purpose of describing specific embodiments only and are not intended to be limiting.

[0047] An Abstract of the Disclosure is provided to enable the reader to quickly ascertain the essence of the technical disclosure. The Abstract is submitted with the understanding that it is not intended to be used to interpret or limit the claims. In addition, it may be understood from the foregoing detailed description that various features may be grouped together as a single embodiment for the purpose of simplifying the disclosure. This method of disclosure is not to be interpreted as limiting the claims. Accordingly, the following claims are incorporated into the detailed description of this specification, and each claim exists as a separate embodiment.

[0048] Examples

[0049] Example 1 comprises an electroplating cup assembly having a cup bottom portion having an opening configured to allow exposure to an electroplating solution of a wafer positioned within the electroplating cup assembly; a lip seal coupled to the cup bottom portion, wherein the lip seal comprises a sealing structure extending upward along the inner edge of the lip seal to a peak configured to contact a seed layer of the wafer and a sacrificial layer of the wafer; and an electroplating cup assembly comprising an electrical contact structure forming a seal together with the lip seal, wherein the electrical contact structure is configured to be coupled to the seed layer at the periphery of the wafer.

[0050] Example 2 includes Example 1, where the peak is coupled to the wall of the sacrificial layer placed along the annular region of the wafer.

[0051] Example 3 includes Example 1, where the seed layer and the sacrificial layer include a copper seed layer.

[0052] Example 4 includes Example 3, where the copper seed layer of the sacrificial layer is 1000 It has a thickness of less than

[0053] Example 5 includes Example 3, wherein the copper seed layer of the sacrificial layer is 1000 with pattern exclusion of at least 0.5 mm to 3000 It has a thickness of

[0054] Example 6 includes Example 1, wherein the bottom of the cup includes a contour and the seal includes a mounting structure having a bottom surface configured to match the contour.

[0055] Example 7 includes Example 1, where the bottom of the cup includes an inner edge, and the inner cup edge of the bottom of the cup and the inner edge of the seal are aligned axially.

[0056] Example 8 is a method comprising the steps of: placing a wafer on an electroplating cup assembly that exposes the surface of the wafer to an electroplating solution, wherein the surface includes a sacrificial layer at the periphery of the wafer; electroplating the exposed surface of the wafer; and removing the plated sacrificial layer of the wafer after electroplating the exposed surface of the wafer.

[0057] Example 9 includes Example 8, and also the sacrificial layer includes an annular ring of the seed layer.

[0058] Example 10 includes Example 8, wherein the step of removing the plated sacrificial layer includes the step of applying an edge-bevel removal tool to the plated sacrificial layer.

[0059] Example 11 includes Example 8, wherein the step of removing the plated sacrificial layer includes the step of etching the plated sacrificial layer from the wafer.

[0060] Example 12 includes Example 8, wherein the electroplating cup assembly comprises: a cup bottom portion having at least partially an opening configured to allow exposure to an electroplating solution on the surface of a wafer positioned within the electroplating cup assembly; a lip seal coupled to the cup bottom portion, wherein the lip seal comprises a sealing structure extending upward along the inner edge of the lip seal to a peak configured to contact a seed layer of the wafer and a sacrificial layer of the wafer; and an electrical contact structure forming a seal with the lip seal, wherein the electrical contact structure is configured to be coupled to the seed layer at the periphery of the wafer.

[0061] Example 13 includes Example 12, where the seed layer includes one of the metals Cu, Ni, SnAg, Sn, or Co.

[0062] Example 14 is a wafer having a seed layer and a sacrificial layer, wherein the sacrificial layer is disposed along the periphery of the wafer on the seed layer; and a system comprising an electroplating cup assembly configured to support the wafer, wherein the electroplating cup assembly comprises: a bottom portion of the cup that at least partially defines an opening configured to allow exposure of the wafer positioned within the electroplating cup assembly to an electroplating solution; a lip seal coupled to the bottom portion of the cup, wherein the lip seal comprises a sealing structure extending upward along the inner edge of the lip seal to a peak configured to contact the seed layer of the wafer and the sacrificial layer of the wafer; and an electrical contact structure forming a seal with the lip seal, wherein the electrical contact structure is configured to be coupled to the seed layer at the periphery of the wafer.

[0063] Example 15 includes Example 14, where the peak is coupled to the wall of the sacrificial layer placed along the annular region of the wafer.

[0064] Example 16 includes Example 14, where the seed layer and the sacrificial layer include a copper seed layer.

[0065] Example 17 includes Example 16, where the copper seed layer of the sacrificial layer is 1000 It has a thickness of less than

[0066] Example 18 includes Example 16, wherein the copper seed layer of the sacrificial layer is 1000 with pattern exclusion of at least 0.5 mm to 3000 It has a thickness of

[0067] Example 19 includes Example 14, wherein the bottom of the cup includes a contour, and the seal includes a mounting structure having a bottom surface configured to match the contour.

[0068] Example 20 includes Example 14, where the bottom of the cup includes an inner edge, and the inner edge of the bottom of the cup and the inner edge of the seal are substantially aligned in the axial direction.

Claims

Claim 1 An electroplating cup assembly configured to support a wafer, comprising: a bottom portion of the cup having an opening configured to allow exposure of the wafer positioned within the electroplating cup assembly to an electroplating solution, wherein the wafer comprises a seed layer and a sacrificial layer, and the sacrificial layer is disposed along the periphery of the wafer on the seed layer; a lip seal coupled to the bottom portion of the cup, wherein the lip seal comprises a sealing structure extending upward along the inner edge of the lip seal to a peak configured to contact the seed layer of the wafer and the sacrificial layer of the wafer; and an electrical contact structure forming a seal together with the lip seal, wherein the electrical contact structure is configured to be coupled to the seed layer at the perimeter of the wafer. Claim 2 An electroplating cup assembly according to claim 1, wherein the peak is coupled to the wall of the sacrificial layer disposed along the annular region of the wafer. Claim 3 An electroplated cup assembly according to claim 1, wherein the seed layer and the sacrificial layer comprise a copper seed layer. Claim 4 In claim 3, the copper seed layer of the sacrificial layer is 1000 Electroplated cup assembly having a thickness of less than (Angstrom). Claim 5 In claim 3, the copper seed layer of the sacrificial layer is 1000 with pattern exclusion of at least 0.5 mm to 3000 Electroplated cup assembly having a thickness of Claim 6 An electroplated cup assembly according to claim 1, wherein the lower portion of the cup includes a contour, and the seal includes a mounting structure having a lower surface configured to match the contour. Claim 7 An electroplated cup assembly according to claim 1, wherein the lower portion of the cup includes an inner cup edge, and the inner edge of the lower portion of the cup and the inner edge of the seal are aligned in the axial direction. Claim 8 A method comprising the steps of: placing the wafer on an electroplating cup assembly that exposes the surface of the wafer to an electroplating solution—the surface comprising a sacrificial layer disposed along the periphery of the wafer on a seed layer of the wafer—; electroplating the exposed surface of the wafer; and removing the plated sacrificial layer of the wafer after electroplating the exposed surface of the wafer. Claim 9 In claim 8, the method comprises the sacrificial layer including an annular ring of the seed layer. Claim 10 In claim 8, the step of removing the plated sacrificial layer comprises applying an edge-bevel removal tool to the plated sacrificial layer. Claim 11 In claim 8, the step of removing the plated sacrificial layer comprises the step of etching the plated sacrificial layer from the wafer. Claim 12 The method of claim 8, wherein the electroplating cup assembly comprises: a cup bottom portion having at least partially an opening configured to allow exposure of the surface of the wafer positioned within the electroplating cup assembly to the electroplating solution; a lip seal coupled to the cup bottom portion—comprising a sealing structure extending upward along the inner edge of the lip seal to a peak configured to contact the seed layer of the wafer and the sacrificial layer of the wafer—; and an electrical contact structure forming a seal together with the lip seal—the electrical contact structure configured to be coupled to the seed layer at the periphery of the wafer. Claim 13 In claim 12, the method wherein the seed layer comprises one of Cu, Ni, SnAg, Sn, or Co metal. Claim 14 A system comprising: an electroplating cup assembly configured to support a wafer having a seed layer and a sacrificial layer disposed along the periphery of the wafer on said seed layer, wherein the electroplating cup assembly comprises: a cup bottom portion defining at least partially an opening configured to allow exposure of the wafer positioned within the electroplating cup assembly to an electroplating solution; a lip seal coupled to the cup bottom portion—the lip seal comprising a sealing structure extending upward along the inner edge of the lip seal to a peak configured to contact the seed layer of the wafer and the sacrificial layer of the wafer—; and an electrical contact structure forming a seal together with the lip seal—the electrical contact structure configured to be coupled to the seed layer at the periphery of the wafer. Claim 15 In claim 14, the system wherein the peak is coupled to the wall of the sacrificial layer disposed along the annular region of the wafer. Claim 16 In claim 14, the system comprises the seed layer and the sacrificial layer including a copper seed layer. Claim 17 In claim 16, the copper seed layer of the sacrificial layer is 1000 A system having a thickness of less than Claim 18 In claim 16, the copper seed layer of the sacrificial layer is 1000 with at least 0.5 mm of pattern exclusion to 3000 A system having the thickness of Claim 19 In claim 14, the lower portion of the cup comprises a contour, and the seal comprises a mounting structure having a lower surface configured to match the contour. Claim 20 A system according to claim 14, wherein the lower portion of the cup includes an inner edge, and the inner edge of the lower portion of the cup and the inner edge of the seal are substantially aligned in the axial direction.

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