Electroplating system and method with increased metal ion concentration

Abstract

This application relates to electroplating methods and electroplating systems. Described are electroplating methods and systems that include adding a starting solution containing metal ions to a catholyte to increase the concentration of metal ions in the catholyte to a first metal ion concentration. The methods and systems further include measuring the concentration of metal ions in the catholyte as the metal ions are electroplated onto a substrate, and the catholyte reaches a second metal ion concentration that is less than the first metal ion concentration. The methods and systems further include adding a portion of an anolyte directly to the catholyte when the catholyte reaches the second metal ion concentration. The addition of the portion of the anolyte increases the concentration of metal ions in the catholyte to a third metal ion concentration that is greater than or about the first metal ion concentration.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of U.S. Patent Application No. 17 / 587,063, filed January 28, 2022, the entire disclosure of which is incorporated herein by reference for all purposes. Technical Field

[0003] This application relates to electroplating methods and electroplating systems. Background Technology

[0004] Integrated circuits are made through a process of creating layers of material with complex patterns on the surface of a substrate. After formation, etching, and other processes on the substrate, metals or other conductive materials are typically deposited or formed to provide electrical connections between components. Because this metallization can be performed after many manufacturing operations, problems that occur during the metallization process can result in costly scrap substrates or wafers.

[0005] Electroplating is performed in an electroplating chamber, with the wafer's mounting side in a liquid electrolyte bath. Electrical contacts on a contact ring contact a conductive layer on the wafer surface. Current flows through the electrolyte and the conductive layer. Metal ions in the electrolyte are deposited onto the wafer, forming a metal layer. Electroplating chambers typically have consumable anodes, which is beneficial for bath stability and cost of ownership. For example, copper consumable anodes are commonly used when plating copper. Copper ions removed from the plating bath are replenished by copper removed from the anode, thus maintaining the metal concentration in the plating bath. While efficient in replacing plating metal ions, using consumable anodes requires a relatively complex and expensive design to allow for their replacement. This complexity increases further when the consumable anode is combined with a diaphragm to prevent electrolyte degradation or oxidation during idle operation.

[0006] Therefore, there is a need to improve systems and methods to produce high-quality devices and structures while protecting the substrate and electroplating bath. This technology addresses these and other needs. Summary of the Invention

[0007] Multiple embodiments of this technology include an electroplating method comprising adding a starting solution containing metal ions to a cathode electrolyte to increase the metal ion concentration in the cathode electrolyte to a first metal ion concentration. The method further includes measuring the metal ion concentration in the cathode electrolyte when the metal ions are electroplated onto a substrate, wherein the cathode electrolyte reaches a second metal ion concentration less than the first metal ion concentration. The method further includes directly adding a portion of an anolyte to the cathode electrolyte when the cathode electrolyte reaches the second metal ion concentration. The addition of the portion of the anolyte increases the metal ion concentration in the cathode electrolyte to a third metal ion concentration greater than or approximately the first metal ion concentration.

[0008] In several other embodiments, the method further includes measuring the pH of the cathodic electrolyte in the cathodic electrolyte and the pH of the anodic electrolyte in the anodic electrolyte. In several further embodiments, the method includes adding a second portion of the anodic electrolyte directly to the cathodic electrolyte when the pH of the cathodic electrolyte is less than or approximately 2. In several further embodiments, the method further includes adding a second portion of the anodic electrolyte directly to the cathodic electrolyte when the difference between the pH of the anodic electrolyte and the pH of the cathodic electrolyte is greater than or approximately 0.2. In several additional embodiments, the concentration of a third metal ion in the cathodic electrolyte is greater than the concentration of metal ions in the initial solution containing metal ions. In many more embodiments, the concentration of a second metal ion in the cathodic electrolyte is less than or approximately 55 g / L. In many more embodiments, the concentration of a third metal ion in the cathodic electrolyte is greater than or approximately 70 g / L. In many more embodiments, the metal ion is selected from the group consisting of copper ions, tin ions, and nickel ions.

[0009] Several embodiments of this technology also include an electroplating method comprising electroplating a metal on a substrate in contact with a cathodic electrolyte comprising electroplatable metal ions and an acid. The method further includes measuring the cathodic electrolyte pH in the cathodic electrolyte and the anodic electrolyte pH of an anodic electrolyte separated from the cathodic electrolyte by a selective ion-exchange membrane. The method also includes directly adding a portion of the anodic electrolyte to the cathodic electrolyte when the difference between the anodic electrolyte pH and the cathodic electrolyte pH is greater than or approximately 0.2.

[0010] In several other embodiments, the method further includes directly adding a portion of the anolyte to the catholyte when the pH of the catholyte is less than or approximately 2. In several other embodiments, the catholyte comprises an inorganic acid selected from the group consisting of sulfuric acid, hydrochloric acid, and nitric acid. In several further embodiments, the method further includes adding a starting solution containing metal ions to the catholyte to increase the metal ion concentration in the catholyte to a first metal ion concentration. The method further includes measuring the metal ion concentration while electroplating the metal onto a substrate until the metal ion concentration reaches a second metal ion concentration less than the first metal ion concentration. The method further includes directly adding an additional portion of the anolyte to the catholyte when the catholyte reaches the second metal ion concentration, wherein the addition of the additional portion of the anolyte increases the metal ion concentration to a third metal ion concentration greater than or approximately the first metal ion concentration. In more embodiments, the second metal ion concentration is less than or approximately 55 g / L, and the third metal ion concentration is greater than or approximately 70 g / L. In other embodiments, the metal plated on the substrate is selected from the group consisting of copper, tin, and nickel.

[0011] Several embodiments of this technology further include an electroplating system comprising a first compartment operable to contain a cathodic electrolyte and a second compartment operable to contain an anodic electrolyte. The first and second compartments are separated by an ion-selective membrane. The system also includes a sensor in the first compartment operable to measure at least one of a cathodic electrolyte pH and a cathodic electrolyte metal ion concentration. The system further includes a conduit between the first and second compartments operable to deliver a portion of the anodic electrolyte to the cathodic electrolyte without allowing a portion of the anodic electrolyte to pass through the ion-selective membrane.

[0012] In several other embodiments, when the sensor in the first compartment measures a metal ion concentration in the cathode electrolyte below or approximately 70 g / L, the conduit transfers a portion of the anolyte to the cathode electrolyte. In further embodiments, when the sensor in the first compartment measures a pH in the cathode electrolyte below or approximately 2, the conduit transfers a portion of the anolyte to the cathode electrolyte. In further embodiments, the system further includes a second sensor in the second compartment, operable to measure at least one of the anolyte pH and the anolyte metal ion concentration. In more embodiments, when the sensor in the first compartment and the second sensor in the second compartment measure a pH difference greater than or approximately 0.2, the conduit transfers a portion of the anolyte to the cathode electrolyte. In more embodiments, the cathode electrolyte and the anolyte comprise metal ions selected from the group consisting of copper ions, tin ions, and nickel ions.

[0013] Compared to conventional techniques, this technology offers numerous advantages. For example, it can generate and maintain electroplating operations with high metal ion concentrations, thereby increasing the rate of metal plating onto the substrate. Furthermore, it reduces the amount of metal ion-containing starting solution required to increase the metal ion concentration in the cathode electrolyte of the plating bath. These and several other embodiments, along with their numerous advantages and structural features, are described in more detail below with reference to the accompanying drawings. Attached Figure Description

[0014] A further understanding of the nature and advantages of the disclosed embodiments can be achieved by referring to the remainder of the specification and accompanying drawings.

[0015] Figure 1 Exemplary operations in a method of operating an electroplating system according to some embodiments of the present technology are shown.

[0016] Figure 2 A schematic diagram of an electroplating system according to some embodiments of the present technology is shown.

[0017] Figure 3 A schematic diagram of an electroplating system according to some embodiments of the present technology is shown.

[0018] Figure 4 A cross-sectional view of an inert anode according to some embodiments of the present technology is shown.

[0019] Figure 5 A schematic diagram of supplementary components according to some embodiments of the present technology is shown.

[0020] Figure 6A schematic cross-sectional view of supplementary components according to some embodiments of the present technology is shown.

[0021] Figure 7 A schematic cross-sectional view of supplementary components according to some embodiments of the present technology is shown.

[0022] Figure 8 A schematic cross-sectional view of supplementary components according to some embodiments of the present technology is shown.

[0023] Figure 9 A schematic perspective view of an anode material container according to some embodiments of the present technology is shown.

[0024] Figure 10 A schematic perspective view of a battery insert according to some embodiments of the present technology is shown.

[0025] Figure 11 A schematic cross-sectional partial view of a battery insert in a supplementary component according to some embodiments of the present technology is shown.

[0026] Several figures in the illustrations are included as schematic representations. It should be understood that these figures are for illustrative purposes only and should not be considered to be drawn to scale unless specifically stated otherwise. Furthermore, these figures are provided as illustrative to aid understanding and may not include all aspects or information compared to a true representation, and may include exaggerated material for illustrative purposes.

[0027] In the figures, similar parts and / or features may have the same numerical reference numerals. Furthermore, various components of the same type can be distinguished by adding letters after the reference numerals to differentiate similar parts and / or features. If only the first numerical reference numeral is used in the specification, the description applies to any similar parts and / or features having the same first numerical reference numeral, regardless of the letter suffix. Detailed Implementation

[0028] The deposition rate of many electroplated metals increases with increasing metal ion concentration in the aqueous solution. Conventional techniques for increasing the metal ion concentration in the electroplating solution include adding more starting solution and evaporating some water from the solution. Unfortunately, each of these techniques introduces problems for electroplating systems using anolyte and catholyte solutions separated by an ion-selective membrane that transports metal ions from the anolyte to the catholyte, where metal plating occurs on the substrate surface.

[0029] In electroplating systems containing both anolyte and catholyte solutions, increasing the metal ion concentration is typically targeted at the catholyte because it is in direct contact with the plated surface of the substrate. For most starting solutions, the added metal ions are also introduced along with the added acid to prevent precipitation from the starting solution. The acid added to the catholyte reduces the rate at which metal ions from the anolyte are transported to the catholyte through the ion-selective membrane. As the acidity difference between the catholyte and anolyte increases, the rate of metal ion transport from the anolyte to the catholyte can be reduced by 50% or more.

[0030] The ion-selective membrane itself also contributes to acidity imbalance by facilitating the transport of acidic hydrogen ions across metal ions from the anolyte to the catholyte. Over time, the ion-selective membrane produces an anolyte with lower acidity and higher metal ion concentration, and a catholyte with higher acidity and lower metal ion concentration. This imbalance in metal ion concentration between the anolyte and catholyte becomes more pronounced during electroplating operations because the increased acidity difference further slows the transport of metal ions from the anolyte to the catholyte.

[0031] Several embodiments of this technology address these problems by supplying a less acidic, higher metal ion concentration anolyte to a more acidic, lower metal ion concentration catholyte during the electroplating operation. In several embodiments, the anolyte is supplied by directly adding it to the catholyte, bypassing the ion-selective membrane. This increases the metal ion concentration in the catholyte while simultaneously reducing its acidity. In other embodiments, the amount of initial solution added and / or water evaporated required to increase the metal ion concentration in the catholyte is reduced. In further embodiments, electroplating operations can be performed at metal ion concentrations higher than those found in the initial solution.

[0032] Figure 1 Exemplary operation of a method 150 for operating an electroplating system according to some embodiments of the present technology is shown. The method can be performed in various processing systems characterized by an anolyte bypass mechanism, including electroplating systems according to several embodiments of the present technology described below. Figure 2An exemplary electroplating system 200 is shown. For illustrative purposes, exemplary operation of method 150 will be described in conjunction with relevant components of electroplating system 200. It should be understood that method 150 may also include one or more optional operations, which may or may not be specifically associated with certain embodiments of the method according to the present technology. It should also be understood that any electroplating system operating according to method 150 may also include one or more additional components or features throughout this disclosure.

[0033] Method 150 includes adding a metal ion-containing starting solution to the cathodic electrolyte at operation 152. In system 200, the starting solution containing the initial metal ions can be added directly to the cathodic electrolyte 204 in the electroplating chamber 202 and / or directly to the cathodic electrolyte in the cathodic electrolyte reservoir 210. In several embodiments, adding the metal ion-containing starting solution can adjust the metal ion concentration to a first metal ion concentration substantially the same as the metal ion concentration in the metal ion-containing starting solution. In other several embodiments, the first metal ion concentration can be less than or about 60 g / L, less than or about 55 g / L, less than or about 50 g / L, or even lower.

[0034] In some embodiments, system 200 may be substantially emptied of the cathode electrolyte before the addition of the metal ion-containing starting solution, and the addition represents the filling or refilling of the system with cathode electrolyte at the start of the electroplating process. In these embodiments, the first metal ion concentration in the cathode electrolyte 204 is the metal ion concentration of the starting solution. In several other embodiments, the metal ion-containing starting solution may be added to system 200 which already contains cathode electrolyte. In these embodiments, the addition operation 152 adjusts the first metal ion concentration in cathode electrolyte 204 or cathode electrolyte reservoir 210 to be closer to the metal ion concentration in the metal ion-containing starting solution. The addition operation 152 may increase or decrease the metal ion concentration to achieve the first metal ion concentration based on the metal ion concentration of the cathode electrolyte pre-existing in system 200.

[0035] Method 150 further includes measuring the metal ion concentration in the cathode electrolyte 204 at operation 154. In several embodiments, the metal ion concentration may be measured by a metal ion sensor 205a located in the electroplating chamber 202 and in fluid contact with the cathode electrolyte 204. During partial electroplating operations, the metal ion concentration in the cathode electrolyte 204 decreases as metal ions are plated onto the substrate. The extent of the decrease depends on several factors, including the plating surface area of ​​the substrate (or substrates), the volume of the cathode electrolyte, the current flowing through the electrodes of system 200, and the metal ion transport rate between the anolyte and the cathode electrolyte. The metal ion transport rate is also affected by many factors, including the absolute and relative metal ion concentrations in the cathode electrolyte and the anolyte, the acidity (pH) of the cathode electrolyte and the anolyte, and the acidity difference between the cathode electrolyte and the anolyte.

[0036] In several embodiments, the measurement of the metal ion concentration in the cathode electrolyte 204 can be continuous or can be performed at intervals before, during, and after the metal is electroplated onto the substrate. In further embodiments, the measurement of the metal ion concentration in the cathode electrolyte 204 can measure a decrease in the metal ion concentration from a first metal ion concentration immediately after the addition of the metal-containing initial solution in operation 152 to a second metal ion concentration lower than the first metal ion concentration. In other embodiments, when measurement operation 154 detects that the metal ion concentration has decreased to the second metal ion concentration or lower, a signal can be sent from sensor 205a to increase the metal ion concentration in the cathode electrolyte 204.

[0037] It should be understood that metal ion concentration measurements can be performed in system 200 at locations other than the cathode electrolyte 204 in the electroplating chamber 202. In several embodiments, the metal ion concentration in the cathode electrolyte held in the cathode electrolyte reservoir 210 can be measured by a metal ion sensor 205b in contact with the cathode electrolyte. In some electroplating operations, the measured value of the metal ion concentration in the cathode electrolyte held in the cathode electrolyte reservoir 210 may vary less than the measured value of the metal ion concentration in the cathode electrolyte 204 held in the electroplating chamber 202. In other electroplating operations, changes in metal ion concentration can be measured more quickly in the cathode electrolyte 204 than in the cathode electrolyte held in the cathode electrolyte reservoir 210. In further several embodiments, metal ion measurements can be performed in both the cathode electrolyte 204 held in the electroplating chamber 202 and the cathode electrolyte reservoir 210r.

[0038] Method 150 may further include measuring the pH of the cathode electrolyte 204 at operation 156. In several embodiments, the pH may be measured by a sensor 205a, which may also measure the concentration of metal ions in the cathode electrolyte 204. In further several embodiments, the pH may be measured by a sensor (not shown) independent of sensor 205a, such as a dedicated pH meter. In more embodiments, the cathode electrolyte pH measured at operation 156 may further include generating a pH signal from a pH sensor in electronic communication with a logic processor (not shown). When the sensor indicates that the cathode electrolyte pH is at or below a threshold level, the logic processor may generate a signal to perform one or more operations to increase the cathode electrolyte pH. As described below, these operations may include directly adding a less acidic anolyte to a more acidic cathode electrolyte. In further embodiments, the pH of the cathode electrolyte that causes the logic processor to generate a signal to initiate one or more pH increase operations may be less than or about 2.5, less than or about 2.4, less than or about 2.3, less than or about 2.2, less than or about 2.1, less than or about 2.0, less than or about 1.9, less than or about 1.8, less than or about 1.7, less than or about 1.6, less than or about 1.5 or less.

[0039] Method 200 may further include measuring the anolyte pH at operation 158. In system 200, the anolyte pH can be measured by contacting one or more sensors 205c and 205d with the anolyte 206 in the electroplating chamber 202 and the anolyte in the anolyte reservoir 212, respectively. In these embodiments, a further operation may compare the anolyte pH with the catholyte pH to determine the pH difference between the anolyte and catholyte. In several embodiments, a pH difference exceeding a threshold may cause a signal to be generated by a pH sensor or a logic processor receiving pH measurement information from a pH sensor. In several other embodiments, the signal may instruct system 200 to perform a pH rebalancing operation to reduce the pH difference between the anolyte and catholyte. These rebalancing operations will be discussed in detail below. In several additional embodiments, the threshold value for the pH difference between the anolyte and the catholyte that causes the pH rebalancing signal to be generated can be greater than or about 0.1, greater than or about 0.2, greater than or about 0.3, greater than or about 0.4, greater than or about 0.5, or greater. For example, a pH rebalancing signal will be generated if the pH of the anolyte 206 exceeds the pH of the more acidic catholyte 204 by greater than or about 0.1, greater than or about 0.2, greater than or about 0.3, greater than or about 0.4, greater than or about 0.5, or greater.

[0040] Method 150 further includes adding a portion of the anolyte directly to the catholyte in operation 160. In several embodiments, operation 160 may increase the metal ion concentration in the catholyte. In further several embodiments, operation 160 may increase the pH of the catholyte and / or decrease the pH difference between the catholyte and the anolyte. Referring to system 200, operation 160 may include directly conveying a portion of the anolyte in anolyte reservoir 212 to the catholyte in catholyte reservoir 210 via conduit 215. The catholy solution in catholyte reservoir 210 supplies an enhanced catholy solution to the catholyte 204 in electroplating chamber 202, characterized by an increased metal ion concentration and / or an increased pH (i.e., a decreased acidity). In several embodiments, after a portion of the anolyte is directly added to the catholyte, the catholyte 204 may be characterized by a metal ion concentration greater than or about 55 g / L, greater than or about 60 g / L, less than or about 65 g / L, greater than or about 70 g / L, greater than or about 75 g / L, or higher. In further embodiments, after a portion of the anolyte is directly added to the catholyte, the pH of the catholyte 204 may be characterized by a concentration greater than or about 2.1, greater than or about 2.2, greater than or about 2.3, greater than or about 2.4, greater than or about 2.5, greater than or about 2.6, greater than or about 2.7, greater than or about 2.8, greater than or about 2.9, greater than or about 3, greater than or about 3.25, greater than or about 3.5, greater than or about 3.75, greater than or about 4, or higher.

[0041] It should be understood that there are other constructions in operation 160 ( Figure 2 (Not shown) A portion of the anolyte can be added directly to the catholyte. In several additional embodiments, a conduit (not shown) can directly deliver a portion of the anolyte in the anolyte reservoir 212 to the catholyte 204 in the electroplating chamber 202. In further embodiments, a conduit (not shown) bypassing the selective ion separator 208 in the electroplating chamber 202 can directly deliver a portion of the anolyte 206 to the catholyte 204 in the electroplating chamber. In further embodiments, operation 160 may be characterized by adding the anolyte directly to the catholyte without passing the delivered anolyte through a separator separating the anolyte and the catholyte.

[0042] In several embodiments, when the anolyte, which is directly added to the catholyte in operation 160, becomes increasingly unbalanced during electroplating, the metal ion concentrations and acidity of the anolyte and catholyte are rebalanced. As described above, electroplating involves removing metal ions from the catholyte in fluid contact with the substrate, as the ions are reduced to a metal layer on the substrate. Removing electroplating metal ions from the catholyte results in a decrease in the metal ion concentration in the catholyte. In electroplating systems according to various embodiments of the present art, such as system 200, most of the metal ions in the catholyte are replenished by the migration of metal ions from the anolyte 206 through an ion-selective membrane 208, which selectively allows metal ions to pass through while blocking the migration of other components of the anolyte and catholyte. In several embodiments, these other components may include catholyte additives, such as inhibitors (e.g., polyethylene glycol), promoters (e.g., bis-(3-sulfopropyl)-disulfide), and leveling agents (e.g., Janus Green B dye) that help to electroplat a uniform metal layer on the substrate. Selective ion-selective membranes prevent additives and metal ions from passing through the membrane, for example, by forming a membrane on an electrode with opposite charge (e.g., a negatively charged additive forms a membrane on the anode).

[0043] In many embodiments, the migration rate of metal ions through the ion-selective membrane 208 is greater than that of hydrogen ions (H ions). + Migration through the membrane is slow. Over time, the replenishment of electroplated metal ions in the cathode electrolyte 204 and the anolyte 206 increases the concentration gradient between the cathode and anolytes. The higher acidity of the cathode electrolyte, due to the rapid migration of hydrogen ions from the anolyte to the cathode electrolyte, also increases the pH gradient. For several reasons, the imbalance of metal ion concentration and pH between the anolyte and cathode electrolyte reduces the rate of metal ion electroplating onto the substrate. Specifically, the decreased metal ion concentration in the cathode electrolyte 204 slows the rate of metal ion transport from the cathode electrolyte to the substrate surface. Another reason is that the increased hydrogen ion concentration in the increasingly acidified cathode electrolyte 204 slows the rate of metal ion migration through the ion-selective diaphragm 208. Adding a portion of the metal ion-rich and hydrogen ion-poor anolyte to the metal ion-poor and hydrogen ion-rich cathode electrolyte can reverse these natural trends in the electroplating process and increase the electroplating rate of metal on the substrate. This reversal can be achieved without adding an additional metal-ion-containing starting solution to the cathode electrolyte 204 or without using conventional methods to concentrate the metal ions in the cathode electrolyte, such as heating the cathode electrolyte to evaporate water.

[0044] Method 150 may further include maintaining the increased metal ion concentration in the cathodic electrolyte during operation 162. As described above, the operation may include migrating metal ions from the anodic electrolyte 206 to the cathodic electrolyte 204 via the ion-selective membrane 208. In several other embodiments, the operation includes adding a portion of the anodic electrolyte directly to the cathodic electrolyte. In several embodiments, these further additions may be made when the measured metal ion concentration in the cathodic electrolyte drops to or below a threshold metal ion concentration. In more embodiments, the threshold metal ion concentration may be less than or about 75 g / L, less than or about 70 g / L, less than or about 65 g / L, less than or about 60 g / L, less than or about 55 g / L, less than or about 50 g / L, or less. In several other embodiments, operation 162 may include periodically adding the anodic electrolyte directly to the cathodic electrolyte during metal plating on the substrate. In several additional embodiments, the anolyte can be added directly to the catholyte at intervals of more than or about 1 minute, more than or about 2 minutes, more than or about 3 minutes, more than or about 4 minutes, more than or about 5 minutes, more than or about 6 minutes, more than or about 7 minutes, more than or about 8 minutes, more than or about 9 minutes, more than or about 10 minutes or greater.

[0045] In several other embodiments, the cathode electrolyte 204 may be stirred or otherwise agitated to facilitate the transport of metal ions from the cathode electrolyte to the substrate surface and to maintain a uniform concentration of metal ions in the cathode electrolyte in contact with the substrate surface. In several other embodiments, the system 200 may further include a stirring unit 211 to stir the cathode electrolyte 204 in the electroplating chamber 202 during the electroplating operation.

[0046] Method 150 may further include performing metal plating on the substrate at operation 164. In several embodiments, performing operation 164 may include removing the substrate from contact with the cathodic electrolyte 204 in the plating chamber 202. In further embodiments, a single substrate may be in contact with the cathodic electrolyte 204 in the plating chamber 202. In further embodiments, two or more substrates may be in contact with the cathodic electrolyte 204 in the plating chamber 202 simultaneously. In still further embodiments, the plating chamber 202 may be operable to hold at least two substrates, at least three substrates, at least five substrates, at least ten substrates, at least fifteen substrates, and at least twenty substrates or more.

[0047] In several other embodiments, method 150 may include measuring one or more of operations 154, 156, and 158. In some embodiments, method 150 may include measuring the metal ion concentration in the cathode electrolyte 204 (i.e., operation 154), but not measuring the pH of the cathode electrolyte (i.e., operation 156) or the pH of the anolyte 206 (i.e., operation 158). In several other embodiments, method 150 may include measuring the pH of the cathode electrolyte 204, but not measuring the metal ion concentration or pH of the anolyte 206. In still other embodiments, method 150 may include measuring the pH of both the cathode electrolyte 204 and the anolyte 206, but not measuring the metal ion concentration of the cathode electrolyte.

[0048] In further embodiments, the metal ion refers to a metal ion capable of being electroplated onto a substrate in contact with the cathodic electrolyte fluid. It should be understood that the starting solution containing metal ions, the cathodic electrolyte, and the anolyte may include other metal ions (e.g., ions of alkali metals and alkaline earth metals) that are not included in the metal ion concentration because they are not electroplated onto the substrate as metals. In further embodiments, the metal ions may include copper ions, tin ions, and nickel ions, as well as other types of metal ions. These metal ions are electroplated onto the substrate surface as metal layers of copper, tin, and nickel, respectively. In further embodiments, the metal ions may be dissolved ions of metal salts that are at least partially soluble in water. In further embodiments, these metal salts may include copper sulfate (CuSO4) and copper chloride (CuCl2), as well as other metal salts.

[0049] In further embodiments, the cathode electrolyte and anolyte can be aqueous solutions or mixtures containing metal ions. In further embodiments, in addition to metal ions, the cathode electrolyte may include one or more additives, such as inhibitors, promoters, and leveling agents, as well as other additives. In further embodiments, the anolyte may lack at least one additive found in the cathode electrolyte. This makes adding a portion of the anolyte directly to the cathode electrolyte to increase the metal ion concentration of the cathode electrolyte more cost-effective than adding a starting solution of the cathode electrolyte containing additives. This technology provides the ability to increase the metal ion concentration of the cathode electrolyte to levels even higher than those found in a starting solution of the cathode electrolyte containing metal ions, without over-concentrating the cathode electrolyte in additives also present in the starting solution containing metal ions.

[0050] In several embodiments, the electroplating system 200 may include additional components that facilitate the electroplating operation. In other embodiments, the electroplating system 200 may include a supplementary component 220 that provides additional metal ions to the anolyte and catholyte during the electroplating operation. In further embodiments, the supplementary component 220 may include a metal ion generating chamber 222, an isolation chamber 226, and a third chamber 228 in contact with the cathode electrode 235. In more embodiments, the metal ion generating chamber 222 and the isolation chamber 226 may be fluidly separated by a first ion-selective membrane 230 operable to transport metal ions and hydrogen ions from the metal ion generating chamber to the isolation chamber. In still other embodiments, the first ion-selective membrane 230 may slow down or prevent the transfer of additives between the metal ion generating chamber 222 and the isolation chamber 226. In further embodiments, the second ion-selective membrane 232 is operable to transport hydrogen ions from the isolation chamber to the third chamber, fluidly separating the isolation chamber 226 from the third chamber 228. In further embodiments, the second ion-selective membrane 232 may slow down or prevent the migration of metal ions and additives from the isolation chamber 226 to the third chamber 228.

[0051] In several embodiments, the anolyte chamber 222 may include a first compartment 223 to contain anolyte material, which is additional metal ions generated by the anolyte contained in a second compartment 225 in fluid contact with the anolyte material. In further embodiments, the anolyte material in the first compartment 223 may also act as an anode, which is electrically connected to a cathode in fluid contact with the catholyte in the catholyte chamber 228. In further embodiments, a portion of the metal ions generated by the anolyte material may be added to the catholyte in the catholyte reservoir 210 and / or the anolyte in the anolyte reservoir 212. During electroplating operations, the additional metal ions help maintain the metal ion concentration in the catholyte and anolyte in the electroplating chamber 202 and reservoirs 210 and 212.

[0052] Figure 3 A schematic diagram of another electroplating system according to some embodiments of the present technology is shown. Figure 3In this electroplating chamber 20, a rotor 24 in a head 22 may be included for holding a wafer 50. The rotor 24 may include a contact ring 30 that can move vertically to engage contact fingers 35 on the contact ring 30 with the downward-facing surface of the wafer 50. During electroplating, the contact fingers 35 may be connected to a negative voltage source. A bellows 32 may be used to seal the internal components of the head 22. A motor 28 in the head may rotate the wafer 50 held in the contact ring 30 during electroplating. The chamber 20 may alternatively have various other types of heads 22. For example, the head 22 may operate with the wafer 50 held in a chuck instead of directly handling the wafer 50, or the rotor and motor may be omitted during electroplating, keeping the wafer stationary. Seals on the contact ring may seal the wafer to seal the contact fingers 35 from the cathode electrolyte during processing. The head 22 may be positioned above an electroplating container 38 of the electroplating chamber 20. One or more inert anodes may be provided in the container 38. In the example shown, the electroplating chamber 20 may include an inner anode 40 and an outer anode 42. Multiple electroplating chambers 20 within the electroplating system may be provided in a column, with one or more robots moving the wafer within the system.

[0053] Figure 4 A cross-sectional view of an inert anode according to some embodiments of the present technology is shown. Figure 4 In this embodiment, anodes 40 and 42 may include wire 45 located within a diaphragm tube 47. Diaphragm tube 47 may have an external protective sheath or cover 49. The diaphragm tube 47, including the electrode wire, may be circular, or optionally formed in a helical or linear array, or take another form suitable for generating an electric field appropriate for the workpiece being processed. In some embodiments, wire 45 may be a 2 mm diameter platinum wire within a diaphragm tube 47 with an inner diameter of 2-3 mm. Wire 45 may also be a platinum-clad wire with a core of another metal (e.g., niobium, nickel, or copper). A resistive diffuser may be provided in a container above the inert anode. A flow space 51 may be provided around wire 45 within the diaphragm tube 47. Although wire 45 may nominally be centered within the diaphragm tube 47, in practice, the position of the wire within the diaphragm tube may vary such that the wire may contact the inner wall of the diaphragm tube at certain locations. Spacers can be used to keep the wire inside the tube, but spacers or other techniques may not be necessary to center the wire inside the diaphragm tube.

[0054] Figure 3The diagram also additionally shows a three-compartment replenishment assembly 70, which will be described in further detail below. During electroplating, the process anolyte can be pumped through a process anolyte circuit comprising an anode diaphragm tube 47 and a process anolyte chamber 150, which serves as the process anolyte source for anodes 40 and 42. The diaphragm tubes forming anodes 40 and 42 can be annular or circular, included within a circular groove 41 of the anode plate 43 of container 38, as shown, with the diaphragm tube resting against the floor of container 38. The replenishment system 70 can be external to chamber 20, as it is a separate unit within the processing system that can be located remotely from the processor. This allows the replenishment assembly to be fluidly coupled to multiple electroplating chambers, where the replenishment assembly replenishes the cathodic electrolyte used by any number of chambers.

[0055] The wires 45 of each anode 40, 42 can be electrically connected to a positive voltage source relative to the voltage applied to the wafer to generate an electric field within the container. Each inert anode can be connected to a power supply channel, or they can be connected to a separate power supply channel via an electrical connector 60 on the container 38. Typically, one to four inert anodes are used. The flow of positive electrolyte through the diaphragm tube can carry gas out of the container. In use, the voltage source can induce a current flow, causing the water in the inert anodes to be converted into oxygen and hydrogen ions, and causing copper ions to be deposited from the cathode electrolyte onto the wafer. The wires 45 in anodes 40 and 42 may be inert and may not chemically react with the anolyte. The wafer 50, or a conductive seed layer on the wafer 50, can be connected to a negative voltage source. During electroplating, the electric field within the container 38 can cause metal ions in the cathode electrolyte to be deposited onto the wafer 50, thereby forming a metal layer on the wafer 50.

[0056] The metal layer electroplated onto wafer 50 can be formed by metal ions in the chamber catholy solution, which move to the wafer surface due to the flow of the chamber catholy solution and ion diffusion in container 38. A catholy solution replenishment system 70 can be fluidly coupled to the electroplating chamber to supply metal ions back to the system catholy solution. The replenishment system 70 may include a chamber catholy solution return line, which may be or includes a pipe or conduit, and a chamber catholy solution supply line 78, which connects to a replenishment assembly 74 in the catholy solution circulation loop. In some embodiments, the catholy solution circulation loop may include an additional catholy solution tank, wherein the chamber catholy solution tank supplies catholy solution to multiple electroplating chambers 20 within the processing system. The catholy solution circulation loop may include at least one pump and may also include other components such as heaters, filters, valves, and any other fluid loops or circulation components. The supplementary component 74 can be connected to the cathode electrolyte return pipe, or the supplementary component 74 can be connected in a separate flow loop for outflow and return to the cathode electrolyte tank.

[0057] Figure 5 A schematic diagram of a supplementary component according to some embodiments of the present technology is shown, and details of the supplementary component, further described below, can be provided. The diagram shows an enlarged schematic diagram of supplementary component 74 as an operating component applicable to any number of specific supplementary component configurations (including those further described below). The supplementary component anolyte can be circulated within supplementary component 74 via a supplementary component anolyte circuit 90, which includes a supplementary component anolyte cell compartment 98 (which may be the first compartment of the supplementary component) and an optional supplementary component anolyte tank 96. In some embodiments, for example, for copper plating, the supplementary component anolyte can be an acid-free copper sulfate electrolyte, but it should be understood that the system can be used for any number of electroplating operations using chemistry and materials suitable for these operations. The anolyte supplementary component within supplementary component 74 may not require a recirculation circuit and may consist only of the anolyte compartment 98. A gas agitator (e.g., a nitrogen agitator) can provide agitation for the supplementary component without the complexity of a recirculation circuit with piping and pumps. Referring again to copper plating systems, as a non-limiting example, if a low-acid electrolyte or anolyte is used, when current passes through the supplementary components, Cu... 2+ Ions, rather than protons, can be transported or moved into the cathode electrolyte via the diaphragm. Gas disturbance can also reduce the oxidation of bulk copper materials.

[0058] Deionized water supply line 124 can supply replenished deionized water to the replenishment component anolyte tank 96 or compartment 98. Bulk plating material 92, such as copper granules, can be provided in the replenishment component electrolyte compartment 98 and can be plated onto wafer 50. A pump can circulate the replenishment component anolyte through the replenishment component electrolyte compartment 98. The replenishment component anolyte can be completely separate from the anolyte supplied to anodes 40 and / or 42. Furthermore, in some embodiments, the anolyte compartment 98 can be used without any replenishment component anolyte circuit 90. For example, a gas agitator or some other pumping system can provide agitation for the anolyte compartment 98 without using the replenishment component anolyte circuit. For example, some embodiments of the anolyte compartment or first compartment may include an anolyte replenishment tank, or the anolyte can simply be circulated within the compartment or two sections of the compartment, as will be further described below.

[0059] Within the replenishment assembly 74, a first cation exchange membrane 104 may be located between the replenishment assembly anolyte in the replenishment assembly anolyte compartment 98 and the cathodic electrolyte in the cathodic electrolyte compartment 106 to separate the replenishment assembly anolyte from the cathodic electrolyte. A cathodic electrolyte return line 72 may be connected to one side of the cathodic electrolyte compartment 106, and a cathodic electrolyte supply line 78 may be connected to the other side of the anolyte compartment 106, allowing the cathodic electrolyte to circulate from container 38 through the cathodic electrolyte chamber. Alternatively, the cathodic electrolyte flow loop through the replenishment assembly 74 may be a separate flow loop from the cathodic electrolyte tank. The first cation exchange membrane 104 allows metal ions and water to pass through the replenishment assembly anolyte compartment 98 into the cathodic electrolyte in the cathodic electrolyte chamber while providing a barrier between the replenishment assembly anolyte and the cathodic electrolyte. Deionized water can be added to the cathode electrolyte to replenish water lost through evaporation, but more commonly, water evaporation can be enhanced to evaporate water that has entered the cathode electrolyte from the anolyte replenishment assembly via electroosmosis. An evaporator may also be included to remove excess water.

[0060] Metal ions flowing into the cathode electrolyte can replenish the concentration of metal ions in the cathode electrolyte. In several embodiments, when metal ions in the cathode electrolyte are deposited on the wafer 50 to form a metal layer in the wafer 50, they can be replaced by metal ions originating from bulk electroplating material 92 in the cathode electrolyte flowing through the cathode electrolyte compartment 106 of the replenishing assembly 74 via the replenishing component anolyte and the first diaphragm 104. In further embodiments, metal ions are added to the cathode electrolyte by directly delivering a portion of the anolyte to the cathode electrolyte through a conduit bypassing the ion exchange membrane.

[0061] An inert cathode 114 may be located in a thiefolyte compartment 112 opposite to the second cation exchange membrane 108. The negative or cathode of a power source 130 (e.g., a DC power source) may be electrically connected to the inert cathode 114. The positive or anode of the power source 130 may be electrically connected to a bulk electroplated material 92 or metal in the supplementary component anolyte compartment 98, applying or generating a voltage difference across the supplementary component 74. The supplementary component electrolyte in the thiefolyte compartment 112 may optionally be circulated through a supplementary component tank 118, with deionized water and sulfuric acid added to the supplementary component electrolyte through inlet 122. The electrolyte in the thiefolyte compartment 112 may include, for example, deionized water with 1-10% sulfuric acid. The inert cathode 114 may be platinum or platinum-clad wire or plate. The second ion exchange membrane 108 helps retain copper ions in the second compartment. Furthermore, the second ion exchange membrane 108 may be specifically configured to retain Cu ions. 2+It remains within the cathode electrolyte. For example, in some embodiments, the second ion-exchange membrane may be a monovalent membrane, which may further restrict the passage of copper through the membrane.

[0062] Return to reference Figure 3 and Figure 4 Chamber 20 may optionally include a current-stealing electrode 46 within container 38, although in some embodiments a current-stealing device may not be included. In some embodiments, the current-stealing electrode 46 may also have current-stealing wires within the current-stealing diaphragm tube, similar to the anode 40 or 42 described above. If a current-stealing electrode is used, a repair electrolyte can be pumped through the current-stealing diaphragm tube. The current-stealing wires can generally be connected to a negative voltage source, which is controlled independently of the negative voltage source connected to the wafer 50 via contact ring 30. The current-stealing diaphragm tube can be connected to the current-stealing electrolyte compartment 112 in the replenishment assembly 74 via a replenishment assembly circulation loop (generally indicated by 82), a replenishment assembly electrolyte return line 84, and a replenishment assembly electrolyte supply line 86. If used, the highly acidic cathodic electrolyte bath in the cathodic electrolyte compartment 106 ensures that the current passing through the diaphragm 108 is predominantly protons rather than metal ions. Thus, the current in the replenishment assembly 74 can replenish copper in the cathodic electrolyte while preventing copper loss through the diaphragm.

[0063] A second cation exchange membrane 108 can be located between the cathode electrolyte in the cathode electrolyte compartment 106 and the supplementary electrolyte in the electro-stealing electrolyte compartment 112. The second cation exchange membrane 108 allows protons to pass from the cathode electrolyte in the cathode electrolyte compartment 106 into the supplementary electrolyte in the electro-stealing electrolyte compartment 112, while limiting the amount of metal ions that might deposit on the inert cathode. The primary function of the electro-stealing electrolyte compartment 112 is to complete the circuitry of the supplementary compartment without plating metal onto the inert cathode 114. The electro-stealing electrolyte compartment 112 can be used with or without an additional tank or circulation loop. The highly acidic electrolyte or cathode electrolyte bath in the cathode electrolyte compartment 106 ensures that the current passing through the membrane 108 is predominantly protons rather than metal ions, thus ensuring that the cathode reaction on the inert cathode 114 is primarily hydrogen evolution. In this way, the current in the supplementary component 74 replenishes the copper in the cathode electrolyte, while preventing copper from being lost through the diaphragm 108.

[0064] During idle operation, when the replenishment component is not in use, the replenishment system 70 stops the flow of cathodic electrolyte through the bulk electroplating material 92 that forms the consuming anode. In some embodiments, the stealing electrolyte can be drained from the stealing electrolyte compartment during idle operation to limit additional loss of metal ions, additives, or other bath components from the cathodic electrolyte due to diffusion or other transport mechanisms of metal ions on the diaphragm 108. However, as mentioned above, retaining the cathodic and anodic electrolytes in their respective compartments and draining both materials can present challenges. Draining the cathodic electrolyte may induce air entrainment during startup, which can adversely affect electroplating. Draining the anodic electrolyte may expose the anode material, leading to oxidation. However, retaining both electrolytes in their respective compartments may create a gradient between the materials on the diaphragm, resulting in the loss of additives from the cathodic electrolyte. Therefore, some embodiments of this technology may include an additional separator that can be used to separate the anodic and cathodic electrolytes in their respective compartments during idle operation.

[0065] Go to Figure 6 The diagram illustrates a schematic cross-sectional view of a supplementary component 600 according to some embodiments of the present technology. The supplementary component 600 may include any feature structure, part, or feature of the supplementary component 74 and may be incorporated into the supplementary system 70 described above. The supplementary system 600 may show additional feature structures of the supplementary component 74 according to some embodiments of the present technology.

[0066] The supplementary component 600 may include a three-compartment battery comprising an anolyte compartment 605 or a first compartment, a cathode electrolyte compartment 610 or a second compartment, and a stealing electrolyte compartment 615 or a third compartment. The component may also include a first ion-exchange membrane 620 between the anolyte and cathode electrolyte compartments, and may include a second ion-exchange membrane 625 between the cathode and stealing electrolyte compartments. Furthermore, as previously described, to overcome problems during idle periods, an additional separator 630 may be included within the anolyte compartment 605, which provides fluid separation between the first compartment portion 607 and the second compartment portion 409 within the anolyte compartment. Each compartment portion of the anolyte compartment can only be accessed by the anolyte in a continuous loop within the anolyte compartment 605, but the additional separator 430 may facilitate operation as described further below.

[0067] The anolyte compartment 605 may include an electrode 606, which may be coupled to a power source as previously described. An anolyte material, such as copper particles or other metallic materials used in electroplating, may be deposited in the battery in contact with the electrode 606. For example, a retainer 608 or a screen may be included to keep the anolyte material close to the electrode and prevent it from contacting the ion-exchange membrane. As described below, a removable container may also be used to ensure that the anolyte material is contained within the anolyte compartment and in contact with the electrode.

[0068] The separator 630 can also be an ion-exchange membrane, which ensures that when the anolyte flows in each section of the anolyte compartment, the first compartment section can be electrically coupled to the second compartment section while simultaneously allowing fluid separation. This fluid separation can be used to fluidly isolate multiple compartments, thereby allowing evacuation operations during idle periods. In some embodiments, a pump 635 or pumping system can be connected to each of the first and second compartment sections of the anolyte compartment 605 and is operable to pump fluid into and / or out of the second compartment of the anolyte compartment. Anolyte can be pumped from the first compartment section 607 into the second compartment section 609, and the anolyte can rise and fill the second compartment section, which can be located between the separator 630 and the first ion-exchange membrane 620. Fluid can be continuously pumped to ensure the consistency of the anolyte within the compartment section. When the fluid fills the second compartment portion of the anolyte compartment 605, the fluid can enter the spillway 638, which allows the anolyte to flow back into the first compartment portion 607, forming a continuous fluid loop in the anolyte compartment 606 between the two portions, as will be explained further below.

[0069] As previously described, the cathode electrolyte compartment 610 can be fluidly coupled to the electroplating chamber and can be filled with cathode electrolyte, which can remain within the cathode electrolyte compartment 610 during idle periods, as further discussed below. The cathode electrolyte compartment 610 can be separated from the electro-stealing electrolyte compartment 615 by a second ion-exchange membrane 625 (which may be a monovalent membrane in some embodiments). The electro-stealing electrolyte compartment can have electro-stealing electrolyte flowing within a space, which may also include an inert cathode 640 electrically coupled to a power source as previously described. Therefore, the power source can operate as a voltage source, coupling the anode material to the inert cathode 640 through the three compartments of the chamber, each compartment being electrically coupled together by a separate electrolyte and ion-exchange membrane.

[0070] Figure 7A schematic cross-sectional view of a supplementary component 700 according to some embodiments of the present technology is shown, and the supplementary component 600 during operation may also be shown. The supplementary component 700 may include any component or feature structure of the previously described system or component, and may be incorporated into the electroplating system as described above.

[0071] As shown, the replenishment assembly 700 may include anolyte in the anolyte compartment 605, which can flow through each of the first and second compartment portions of the anolyte compartment during a first replenishment operation of ions into the catholyte. In other words, during the first replenishment operation, the pump 635 can operate in a first configuration to flow the anolyte from the first compartment portion of the anolyte compartment 605 to the second compartment portion. As shown, the anolyte can then contact a first ion-exchange membrane adjacent to the catholyte compartment, and the catholyte can flow toward the opposite side of the membrane. The anolyte can continue to flow upward through the second compartment portion of the anolyte compartment and can flow back to the first compartment portion of the anolyte compartment 605 above the overflow channel 638. The overflow channel 648 can operate as a fluid path extending above the separator to create a fluid loop that can flow continuously during operation.

[0072] Figure 8 A schematic cross-sectional view of a supplementary component 800 according to some embodiments of the present technology is shown, and the supplementary component 600 during operation may also be shown. The supplementary component 800 may include any component or feature structure of the previously described system or component, and may be incorporated into the electroplating system as described above.

[0073] As shown, the supplementary component 800 may include anolyte in the anolyte chamber 605, which may be retained in the first compartment portion 607 during the second idle state of the system operation, while being discharged from the second compartment portion 609 of the anolyte chamber 605. In other words, during the second idle or standby state of the system operation, the pump 635 may operate in a second setting (which may be the opposite of the first setting) to discharge anolyte from the second compartment portion 609 and pump the anolyte back to the first compartment portion 607 of the anolyte chamber 605. As shown, the first compartment portion 607 may include an additional top space volume within the compartment portion, which may allow the entire volume of the second compartment portion 609 to be pumped back to the first compartment portion 407 of the anolyte chamber.

[0074] During the idle period, the electro-stealing electrolyte compartment 615 can similarly drain the electro-stealing electrolyte, which prevents additional copper from migrating through the second ion-exchange membrane and being plated on the inert cathode. The cathode electrolyte can be retained in the cathode electrolyte compartment, which keeps the entire cathode electrolyte flow path to the plating chamber full, thus preventing air entrainment in the loop. This configuration provides several benefits, including maintaining the separation of all fluids within the replenishment assembly during the idle period. Furthermore, each ion-exchange membrane (which may include separator 630 as a third ion-exchange membrane) can be kept in contact with the electrolyte along its surface. For example, as shown, the first ion-exchange membrane can be kept in contact only with the cathode electrolyte during the idle period and can be substantially free of or substantially free of anolyte, minus the amount of residual anolyte that may remain on the membrane. This ensures that the membrane does not dry out during the idle period, thus preventing membrane breakage and failure. Additionally, the anolyte material retained in the first compartment portion 607 can be kept completely submerged in the anolyte, which prevents oxidation. Therefore, by incorporating an additional separator into the second compartment portion of the anolyte compartment, an idle state configuration that restricts or prevents the migration of stagnant fluids across the membrane can be created.

[0075] Go to Figure 9 A schematic perspective view of an anode material container 900 according to some embodiments of the present technology is shown. As previously described, the anode material, such as copper particles or a material for supplementing metal ions, may be included within an anode electrolyte compartment, such as a first compartment portion of the anode electrolyte compartment, where the anode electrolyte can be maintained during operation and idle states. In some embodiments, the container 900 may include a compartment 905 that can hold the anode material to prevent contact with the ion-exchange membrane, which could result in tearing or other punctures to the membrane. The compartment 905 may include a front screen 910 that allows the anode electrolyte to flow through the compartment during operation. Furthermore, as shown, an electrode 915 may extend into the compartment, which further ensures electrical communication with the anode material. For example, the compartment 905 may be conductive, which ensures electrical contact between the anode material and a power source. It should be understood that the container 900 can be incorporated into any of the components or constructions described above.

[0076] Figure 10A schematic perspective view of a battery insert 1000 according to some embodiments of the present technology is shown. In some embodiments, the battery insert 1000 may include a cathode electrolyte compartment to limit the amount of fluid flowing through the compartment at any given time. During idle periods, a certain volume of cathode electrolyte may be retained in the cathode electrolyte compartment and may be in contact with a first ion-exchange membrane and a second ion-exchange membrane. Additives may still be present from the cathode electrolyte onto the membranes and may not be fully reabsorbed into the cathode electrolyte upon restart. Therefore, in some embodiments, by reducing the volume of cathode electrolyte in the cathode electrolyte compartment, additional loss of additives can be limited or prevented.

[0077] The battery insert 1000 may define one or more of a plurality of fluid channels 1005 passing through the insert. Holes 1010 may be formed through both ends of the battery insert along the direction of the formed channels 1005. Figure 11 A schematic cross-sectional partial view of a battery insert 1000 in a supplementary assembly according to some embodiments of the present technology is shown, as in the cathode electrolyte compartment previously described. It should be understood that the battery insert 1000 can be included in any of the components or configurations described above. As shown, the battery insert 1000 can extend laterally within the cathode electrolyte compartment to limit the available space for cathode electrolyte flow. In some embodiments, although a small amount of fluid space may be maintained between components to ensure adequate wetting of the membrane, the battery insert 1000 can contact one or both of the first ion-exchange membrane or the second ion-exchange membrane. Recessed channels 1105 can be formed within the top and bottom of the battery insert, providing fluid passages to orifices 1010. Orifices 1010 can supply fluid from the recessed channels into fluid passages vertically defined through the battery insert. The battery insert according to this technology can limit the space in the cathode electrolyte compartment or any other compartment to greater than or about 10%, and can limit the space in the compartment to greater than or about 20%, greater than or about 30%, greater than or about 40%, greater than or about 50%, greater than or about 60%, greater than or about 70%, greater than or about 80%, greater than or about 90% or more.

[0078] The aforementioned systems include conduits and replenishment components for delivering a portion of the anolyte to the catholyte to maintain increased metal ion concentrations in both the anolyte and catholyte. These systems are operable for electroplating operations. These electroplating operations may include driving a voltage via the replenishment component, which may include a three-compartment assembly comprising any component, feature structure, or feature of the aforementioned components or devices. The assembly may include a separator within the anolyte compartment that facilitates idle operation as described above. The method may include providing ions of anolyte material. The ions may be metal ions supplied to or replenishing the catholyte flowing through the catholyte compartment of the assembly.

[0079] In some embodiments, the voltage between the anode material and the cathode can be reversed after the electroplating operation, and the cathode can be an inert cathode. This allows any material that may have entered the stealing electrolyte through the cathode electrolyte and been plated on the inert cathode to be returned to the plating solution and removed from the inert cathode. In some embodiments, the voltage reversal operation can be performed periodically. While the system can operate for a long period followed by a prolonged voltage reversal, in some embodiments, the reversal can be performed at more regular intervals within shorter periods. This can be beneficial for retaining the metal within the electrolyte and may limit the formation of dendrites or other defects in the anode material. For example, in some embodiments, the reversal can be performed periodically, such that the time interval between standard operating cycles is less than or about 60 minutes, and the reversal can be performed for less than or about 50 minutes, less than or about 40 minutes, less than or about 30 minutes, less than or about 20 minutes, less than or about 10 minutes, or less.

[0080] In some embodiments, the method may include operations performed prior to the system being idle. For example, in an alternative operation, a pump may be operated to pump the anolyte from a second compartment portion of the anolyte compartment back to a first compartment portion of the anolyte compartment, where the anolyte material may be contained. Pumping may discharge the anolyte from the second compartment portion and may remove the anolyte so that it does not come into fluid contact with the ion-exchange membrane located between the anolyte compartment and the catholyte compartment. In some embodiments, the ion-exchange membrane may remain free of anolyte, except for any residual amount retained within the membrane during purging or pump-drying operations.

[0081] Several embodiments of this technology allow for prolonged electroplating operations at increased metal ion concentrations in the cathodic electrolyte. The increased metal ion concentration increases the rate of metal deposition on the substrate during the electroplating operation, increasing the throughput of the substrate through the electroplating system. In several embodiments, the increased metal ion concentration is maintained for an extended period by directly adding a portion of the anolyte from the electroplating system to the cathodic electrolyte. The metal ion-rich anolyte increases the concentration of metal ions depleted by the electroplating operation in the cathodic electrolyte. A less acidic anolyte also raises the pH of the cathodic electrolyte, which further enhances the rate of metal ion transport from the anolyte to the cathodic electrolyte through the ion-selective membrane. Adding a portion of the anolyte directly to the cathodic electrolyte allows electroplating operations to be performed at metal ion concentrations exceeding those in the initial metal ion-containing solution, and these high concentration levels are maintained even when metal ions are removed from the cathodic electrolyte during the electroplating operation.

[0082] In the foregoing description, numerous details have been set forth for illustrative purposes to provide an understanding of various embodiments of the present technology. However, it will be apparent to those skilled in the art that certain embodiments may be implemented without some of these details or with additional details. For example, other substrates that may benefit from the described wet process technology may also be used with this technology.

[0083] Having disclosed several embodiments, those skilled in the art will recognize that various modifications, alternative constructions, and equivalents can be used without departing from the spirit of the embodiments. Furthermore, to avoid unnecessarily obscuring the prior art, several known processes and elements have not been described. Therefore, the above description should not be considered as limiting the scope of this technology.

[0084] Where a numerical range is provided, it should be understood that, unless the context explicitly specifies otherwise, the values ​​between the upper and lower limits of the range, each minimum fraction between the lower limit unit, should also be specifically disclosed. Any narrower range between any specified value or unspecified intermediate value within a specified range and any other specified value or intermediate value within the specified range is included. The upper and lower limits of these smaller ranges may independently include or exclude the range, and each range that includes any one, neither, or both limits within the smaller range is also included in the technique, subject to any specific exclusion limits within the specified range. If the range includes one or two limits, then ranges that do not include one or both are also included. Where multiple values ​​are provided in the list, any range that includes or is based on any of these values ​​will similarly be specifically disclosed.

[0085] As used herein and in the appended claims, unless the context clearly specifies otherwise, the singular forms “a,” “an,” and “the” include plural references. Thus, for example, a reference to “a material” includes a plurality of such materials, a reference to “the channel” includes references to one or more channels and one or more channel equivalents known to those skilled in the art, and so on.

[0086] Furthermore, the terms “comprise(s)”, “comprising”, “contain(s)”, “containing”, “include(s)”, and “including” used in this specification and the foregoing claims are intended to specify the presence of the stated feature structure, integer, component, or operation, but do not exclude the presence or addition of one or more other feature structures, integers, components, operations, or groups.

Claims

1. An electroplating method, characterized in that, include: A starting solution containing metal ions is added to the cathode electrolyte to increase the metal ion concentration in the cathode electrolyte to a first metal ion concentration; When metal ions are electroplated onto the substrate, the concentration of the metal ions in the cathode electrolyte is measured, wherein the cathode electrolyte reaches a second metal ion concentration that is less than the first metal ion concentration; When the cathode electrolyte reaches the second metal ion concentration, a portion of the anolyte is directly added to the cathode electrolyte, wherein the addition of the portion of the anolyte increases the metal ion concentration in the cathode electrolyte to a third metal ion concentration that is greater than or equal to the first metal ion concentration. The pH values ​​of the cathodic electrolyte and the anodic electrolyte were measured. When the difference between the pH of the anolyte and the pH of the catholyte is greater than or equal to 0.2, the second part of the anolyte is directly added to the catholyte.

2. The electroplating method according to claim 1, wherein, The method further includes: when the pH of the cathode electrolyte is less than or equal to 2, directly adding the second portion of the anolyte to the cathode electrolyte.

3. The electroplating method according to claim 1, wherein, The concentration of the third metal ion in the cathode electrolyte is greater than the concentration of the metal ion in the initial solution containing metal ions.

4. The electroplating method according to claim 1, wherein, The concentration of the second metal ion in the cathode electrolyte is less than or equal to 55 g / L.

5. The electroplating method according to claim 1, wherein, The concentration of the third metal ion in the cathode electrolyte is greater than or equal to 70 g / L.

6. The electroplating method according to claim 1, wherein, The metal ions are selected from the group consisting of copper ions, tin ions, and nickel ions.

7. An electroplating method, characterized in that, include: Electroplating metals on a substrate in contact with a cathodic electrolyte containing electroplatable metal ions and acids; The pH of the cathodic electrolyte in the cathodic electrolyte and the pH of the anodic electrolyte in the anodic electrolyte separated from the cathodic electrolyte by a selective ion-exchange membrane are measured. and When the pH difference between the anolyte and the catholyte is greater than or equal to 0.2, a portion of the anolyte is directly added to the catholyte.

8. The electroplating method according to claim 7, wherein, The method further includes adding a portion of the anolyte directly to the catholyte when the pH of the catholyte is less than or equal to 2.

9. The electroplating method according to claim 7, wherein, The cathode electrolyte comprises inorganic acids selected from the group consisting of sulfuric acid, hydrochloric acid, and nitric acid.

10. The electroplating method according to claim 7, wherein, The method further includes adding a starting solution containing metal ions to the cathode electrolyte to increase the metal ion concentration in the cathode electrolyte to a first metal ion concentration; The concentration of metal ions is measured while the metal is being electroplated onto the substrate, until the concentration of metal ions reaches a second metal ion concentration that is less than the first metal ion concentration. and When the cathode electrolyte reaches the second metal ion concentration, an additional portion of the anolyte is directly added to the cathode electrolyte, wherein the addition of the additional portion of the anolyte increases the metal ion concentration to a third metal ion concentration that is greater than or equal to the first metal ion concentration.

11. The electroplating method according to claim 10, wherein, The concentration of the second metal ion in the cathode electrolyte is less than or equal to 55 g / L, and the concentration of the third metal ion in the cathode electrolyte is greater than or equal to 70 g / L.

12. The electroplating method according to claim 7, wherein, The metal electroplated on the substrate is selected from the group consisting of copper, tin, and nickel.

13. An electroplating system, characterized in that, include: A first compartment operable to contain a cathode electrolyte and a second compartment operable to contain an anolyte, wherein the first compartment and the second compartment are separated by an ion-selective membrane; The sensor in the first compartment is operable to measure at least one of the pH of the cathode electrolyte and the concentration of metal ions in the cathode electrolyte; The second sensor in the second compartment is operable to measure at least one of the anolyte pH and the anolyte metal ion concentration; and A conduit between the first and second compartments, operable to deliver a portion of the anolyte to the catholyte without allowing the portion of the anolyte to pass through the ion-selective membrane. When the sensor in the first compartment and the second sensor in the second compartment measure a pH difference greater than or equal to 0.2, the conduit transfers a portion of the anolyte to the catholyte.

14. The electroplating system according to claim 13, wherein, When the sensor in the first compartment measures that the concentration of metal ions in the cathode electrolyte is less than or equal to 70 g / L, the conduit transfers a portion of the anolyte to the cathode electrolyte.

15. The electroplating system according to claim 13, wherein, When the sensor in the first compartment measures that the pH of the cathode electrolyte is less than or equal to 2, the conduit transfers a portion of the anolyte to the cathode electrolyte.

16. The electroplating system according to claim 13, wherein, The cathode electrolyte and the anode electrolyte comprise metal ions selected from the group consisting of copper ions, tin ions, and nickel ions.

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