Electrodeposition system using ion exchange membrane irrigation

Abstract

Examples disclosed relate to irrigating an ion exchange membrane in an electrodeposition system. In one example, the electrodeposition system includes a fluid distribution system including a membrane assembly including a membrane frame configured to support an ion exchange membrane defining a boundary of a cathode chamber. The fluid dispensing system also includes a high resistance dummy anode (HRVA) located between the membrane frame and the substrate holder; a catholyte circulation loop operable to flow catholyte in a first direction across a surface of the HRVA facing the substrate holder; and a plurality of flow barriers extending between the membrane frame and the HRVA in a second direction transverse to the first direction. Irrigation conduits are located between adjacent flow barriers. Each irrigation conduit is configured to receive the catholyte from the catholyte circulation loop and direct the catholyte to the membrane assembly via a plurality of emitters.

Description

Background Art

[0001] Electroplating can be used in integrated circuit processing to deposit conductive films on substrates. Electroplating involves electrochemically reducing dissolved ions of a selected metal to an elemental state on a substrate to form a film of the selected metal. The electroplating system includes: a cathode chamber through which a catholyte flows; and an anode chamber through which an anolyte flows. An ion exchange membrane is located between the cathode chamber and the anode chamber. The ion exchange membrane selectively allows some ions to pass from the anolyte to the catholyte while blocking other ions and organic additives from passing. Summary of the invention

[0002] This summary is provided to introduce a selection of concepts in a simplified form, which will be further described in the specific implementation schemes below. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not limited to implementations that address any or all of the disadvantages mentioned in any part of this disclosure.

[0003] Disclosed examples relate to actively irrigating an ion exchange membrane in an electrodeposition system. In an example system, the electrodeposition system includes a fluid distribution system. The fluid distribution system includes a membrane assembly, which includes a membrane frame configured to support an ion exchange membrane, which defines a boundary of a cathode chamber. The fluid distribution system also includes: a high resistance virtual anode (HRVA) located between the membrane frame and a substrate holder; a catholyte circulation loop operable to cause catholyte to flow in a first direction across a surface of the HRVA facing the substrate holder; and a plurality of flow barriers extending between the membrane frame and the HRVA in a second direction transverse to the first direction. An irrigation conduit is located between adjacent flow barriers. Each irrigation conduit is configured to receive catholyte from the catholyte circulation loop and direct the catholyte to the membrane assembly via a plurality of emitters.

[0004] In some such examples, the flow barrier is alternatively or additionally integrated with the membrane frame.

[0005] In some such examples, adjacent flow barriers alternatively or additionally define opposing walls of segmented volumes, and wherein the flow barriers alternatively or additionally include apertures proximate the membrane frame that fluidly couple adjacent segmented volumes.

[0006] In some such examples, the irrigation conduit is alternatively or additionally formed in a distribution manifold that is fluidly coupled to the catholyte circulation loop.

[0007] In some such examples, the distribution manifold is alternatively or additionally fluidly coupled to the catholyte circulation loop via an inlet manifold of the membrane frame.

[0008] In some such examples, the distribution manifold is alternatively or additionally fluidly coupled to the inlet manifold of the membrane frame via two or more inlet ports.

[0009] In some such examples, the distribution manifold alternatively or additionally includes one or more outlet ports opposite the two or more inlet ports.

[0010] In some such examples, the membrane frame alternatively or additionally comprises a grid structure comprising a plurality of openings that expose the ion exchange membrane.

[0011] In some such examples, the emitters are alternatively or additionally positioned to discharge catholyte toward intersections of the grid structure.

[0012] In some such examples, the emitters are alternatively or additionally positioned to discharge catholyte toward alternating intersections of the grid structure.

[0013] Another example provides a fluid distribution system for an electrodeposition system. The fluid distribution system includes a membrane frame configured to support an ion exchange membrane, the membrane frame including a grid structure and a plurality of flow barriers extending from the grid structure. The fluid distribution system also includes a plurality of irrigation conduits, each of the plurality of fluid conduits being configured to be positioned between adjacent flow barriers to receive a cathode electrolyte from a cathode electrolyte circulation loop and direct the cathode electrolyte to a membrane assembly via a plurality of emitters.

[0014] In some such examples, the fluid barrier is alternatively or additionally integrated with the membrane frame.

[0015] In some such examples, the irrigation conduits are alternatively or additionally formed in a distribution manifold that is fluidly coupled to an inlet manifold of the membrane frame via two or more inlet ports.

[0016] In some such examples, the distribution manifold alternatively or additionally includes one or more outlet ports opposite the two or more inlet ports.

[0017] In some such examples, the mesh structure alternatively or additionally includes a plurality of openings that expose the ion exchange membrane, and wherein the emitters are positioned to discharge catholyte toward intersections of the mesh structure.

[0018] In some such examples, the emitters are alternatively or additionally positioned to discharge catholyte toward alternating intersections of the grid structure.

[0019] Another example provides a method of irrigating an ion exchange membrane in an electrodeposition system. The method includes flowing a catholyte in a first direction across a HRVA, the HRVA being separated from the ion exchange membrane by a membrane frame, the ion frame comprising a plurality of flow barriers extending from the membrane frame to the HRVA in a second direction transverse to the first direction. The method further includes diverting some of the catholyte to a distribution manifold comprising irrigation conduits located between adjacent flow barriers, each irrigation conduit being configured to direct the catholyte to the membrane frame via a plurality of emitters.

[0020] In some such examples, transferring the cathode electrolyte to the distribution manifold alternatively or additionally includes: transferring the cathode electrolyte via two or more inlet ports of the inlet manifold fluidly coupled to the membrane frame, and the method alternatively or additionally includes transferring the cathode electrolyte to one or more outlet ports of the distribution manifold, the one or more outlet ports being located opposite the inlet ports.

[0021] In some such examples, directing catholyte toward the membrane frame via a plurality of emitters alternatively or additionally includes: discharging catholyte toward intersections of a lattice structure of the membrane frame, the lattice structure including a plurality of openings exposing the ion exchange membrane.

[0022] In some such examples, draining the catholyte toward intersections of the grid structure alternatively or additionally includes draining the catholyte toward alternating intersections of the grid structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A block diagram of an exemplary electrodeposition tool is shown.

[0024] Figure 2 An exemplary electrodeposition cell including a fluid distribution system is schematically depicted.

[0025] Figure 3 An exemplary fluid distribution system for an electrodeposition cell is depicted.

[0026] Figure 4 An exemplary membrane assembly of an electrodeposition cell including a fluid distribution system is depicted.

[0027] Figure 5 Depicted Figure 4 An exemplary distribution manifold and gasket for the membrane assembly.

[0028] Fig. 6A and6B Exemplary structures of distribution manifolds and gasket assemblies are depicted.

[0029] Figure 7 The flow focusing manifold of the membrane module is schematically depicted.

[0030] Figure 8 An exemplary irrigation method utilizing a flow focusing manifold of a distribution manifold is schematically depicted.

[0031] Fig. 9 An exemplary curve of the inlet pressure in a flow focusing membrane module is shown.

[0032] Fig.10 A flow chart is shown describing an exemplary method for irrigating an ion exchange membrane in an electrodeposition system. DETAILED DESCRIPTION

[0033] The term "anode" may generally refer to a conductive structure where electrochemical oxidation occurs during an electroplating process.

[0034] The term "anode chamber" may generally refer to a physical structure configured to house at least one anode and an anolyte and to provide selective separation from a cathode chamber.

[0035] The term "anolyte" may generally refer to the solution used in the anode compartment during an electroplating process.

[0036] The term "pore" may generally refer to an opening that allows solution to flow between adjacent volumes.

[0037] The term "cathode" may generally refer to a conductive layer that grows on a substrate by electrochemical reduction of ions during an electroplating process.

[0038] The term "cathode chamber" may generally refer to a physical structure configured to house at least one cathode and a catholyte and to provide selective separation from an anode chamber.

[0039] The term "catholyte" may generally refer to the solution used in the cathode chamber during an electroplating process.

[0040] The term "circulation loop" may generally refer to the path along which a liquid is recirculated over time. The term circulation loop may generally refer to the circulation loop of the anolyte and may also generally refer to the circulation loop of the catholyte.

[0041] The term "distribution manifold" may generally refer to a structure that allows a solution to be transferred from one conduit into multiple conduits.

[0042] The terms "electroplating," "plating," "deposition," and variations thereof may generally refer to a process in which dissolved ions of one or more metals are reduced on a substrate surface to form a film of the one or more metals.

[0043] The term "electrodeposition system" may generally refer to a machine configured to perform electrodeposition.

[0044] The term "emitter" may generally refer to a structure that directs the flow of solution out of a conduit.

[0045] The term "flow barrier" may generally refer to a structure that prevents the flow of a liquid or solution in a given direction.

[0046] The term "fluid distribution system" may generally refer to a series of conduits, tubes, manifolds, pumps, inlets, and outlets configured to distribute fluids of an electrodeposition system.

[0047] The term "grid structure" may generally refer to an array of component structures that intersect at intersection points to form a two-dimensional network with openings between the component structures.

[0048] The term "high resistance virtual anode" (HRVA) may generally refer to an ionically resistive structure located between the substrate holder and the anode of the electroplating tool through which ions flow from the anode to the cathode during electroplating. The HRVA approximates a reasonably constant and uniform current source adjacent to the cathode.

[0049] The term "inlet manifold" may generally refer to a set of chambers or conduits that draws in fluid from a source and distributes the fluid to one or more locations.

[0050] The term "inlet port" may generally refer to a structure that serves as an inlet for a fluid to enter a channel.

[0051] The term "intersection point of a lattice structure" may generally refer to a point or area where component structures of a lattice structure intersect at an angle.

[0052] The term "ion exchange membrane" may generally refer to a semipermeable membrane that allows the transport of specific dissolved ions but does not allow the transport of other dissolved ions or electrically neutral molecules.

[0053] The term "irrigation conduit" may generally refer to a set of tubes configured to receive catholyte at an inlet and discharge the catholyte toward an ion exchange membrane via one or more emitters.

[0054] The term "membrane module" may generally represent a set of components comprising at least an ion exchange membrane, a membrane frame and a portion of a catholyte circulation loop.

[0055] The term "membrane frame" may generally refer to a device that supports an ion exchange membrane.

[0056] The term "outlet port" may generally refer to a structure that acts as an outlet for fluid to exit from a channel.

[0057] The term "segment volume" may generally refer to the volume between flow barriers.

[0058] The term "substrate" refers to any object upon which a film can be deposited.

[0059] The term "substrate holder" may generally refer to any structure used to support a substrate during an electrodeposition process.

[0060] In the semiconductor processing industry, there is an increasing demand for rapid electrodeposition of metals on substrates while maintaining high uniformity. To meet this demand, electroplating techniques are trending toward higher plating currents, cooler plating bath temperatures, and chemicals that help increase plating rates. For example, the catholyte and anolyte solutions may contain metal salts at concentrations close to saturation. However, such conditions may result in the deposition of metal salt precipitates that form in the electroplating tool over time.

[0061] As a more specific example, to achieve a relatively high copper electroplating growth rate, the electroplating current may exceed 10 amps. In addition, the catholyte and anolyte may contain copper sulfate (CuSO 4 ), sulfuric acid (H 2 SO 4 ) and other possible supporting additives. Copper electroplating can use a cation exchange membrane to separate the anolyte chamber and the catholyte chamber to prevent oxidation of organic additives at the anode. An exemplary cation exchange membrane may include a sulfonated tetrafluoroethylene-based fluoropolymer copolymer. Metal ions passing from the anolyte through the cation exchange membrane to the catholyte increase the concentration of metal ions in the catholyte adjacent to the cation exchange membrane. Such a local increase in concentration may cause the catholyte solution at the cation exchange membrane to be oversaturated in some cases. Oversaturation may be a particular problem when the catholyte stagnates on the membrane surface. This may cause metal salt precipitates to form on the cation exchange membrane and / or adjacent structures. Low convection of the catholyte at the membrane may also lead to precipitation and crystal growth. Over time, the accumulation of precipitation may lead to partial passivation of the cation exchange membrane. This may have a negative impact on the uniformity of the plated film on the substrate.

[0062] At present, a strategy for recovering the target substrate deposition profile by tools encountering precipitation accumulation is manual intervention. Manual intervention may include removing / replacing the film and parts affected by the encounter. Such intervention may be time-consuming and relatively expensive at least due to the cost of parts and the impact on the tool's usable time. Other strategies, such as reducing metal ion concentration and / or the current used for electroplating, may reduce the effectiveness of the tool. The plating bath temperature can be increased, but this may require the introduction of an additive. Such an additive may affect the electroplating process.

[0063] Accordingly, multiple examples are disclosed that involve irrigating an ion exchange membrane to reduce cathode electrolyte stagnation at the membrane. Reducing cathode electrolyte stagnation can help reduce the accumulation of metal salt precipitates. The disclosed examples utilize a fluid distribution system to increase the flow at the ion exchange membrane. Furthermore, the disclosed examples can focus the flow directly on the membrane itself. The disclosed examples can help avoid parts replacement caused by precipitation accumulation. This can reduce the overall impact of precipitation removal on the tool usable time. In addition, reducing precipitation accumulation can promote more consistent and uniform electroplating over time. The disclosed examples are primarily described in the context of copper electrodeposition tools and the accumulation of copper sulfate crystals at ion exchange membranes. However, the disclosed examples can be applied to any suitable chemical on any suitable electrodeposition tool. The disclosed process is non-invasive. Therefore, the disclosed process can be performed without destroying the plane of the electrodeposition tool.

[0064] For example, a membrane frame configured to support an ion exchange membrane can be configured to transfer some of the cathode electrolyte solution to a distribution manifold that directs flow across the ion exchange membrane surface. The flow helps reduce the risk of stagnant fluid, particularly near the corners and outlet areas of the membrane frame. The flow can therefore help prevent crystal formation.

[0065] Figure 1A block diagram schematically depicts an exemplary electrodeposition tool 100. The electrodeposition tool 100 includes an electrodeposition unit 102 that includes an anode chamber 104 and a cathode chamber 106. The electrodeposition tool 100 also includes: an ion exchange membrane 108 that separates the anode chamber 104 and the cathode chamber 106; and an HRVA 109 in the cathode chamber 106. The anode chamber 104 includes an anode 110. The anode chamber 104 also includes anolyte. The cathode chamber 106 includes catholyte. The catholyte includes ionic species that are electrochemically reduced to deposit in metallic form on the cathode layer of the substrate 111. In some examples, the anode 110 may include a consumable anode formed of the deposited metal. In other examples, the anode 110 may include an inert anode. When the anode 110 includes the deposited metal, the electrochemical oxidation of the anode 110 at least partially replenishes the ionic species consumed by the electroplating process. Bulk anolyte solution and / or catholyte solution may sometimes be added to replenish these ionic species.

[0066] The ion exchange membrane 108 prevents organic and some ionic species from shuttling between the cathode chamber 106 and the anode chamber 104 while allowing selected ions to shuttle from the anode chamber 104 to the cathode chamber 106. For example, the ion exchange membrane 108 may allow metal ions to shuttle from the anode chamber 104 to the cathode chamber 106 for electroplating. As described above, the HRVA 109 includes an ion resistance element that approximates an appropriate constant and uniform current source adjacent to the cathode of the substrate.

[0067] The substrate holder 112 is coupled to a substrate holder movement system 113 that includes a lift 114 that is configured to adjust the space between the substrate holder 112 and the HRVA 109. For example, the lift 114 may lower the substrate holder 112 to place the substrate 111 in the catholyte for electroplating. The lift 114 may also raise the substrate holder 112 from the catholyte after electroplating. The substrate holder movement system 113 may also include components to control the opening and closing of the substrate holder 112.

[0068] The catholyte may be circulated between the cathode chamber 106 and the catholyte reservoir 120 by a combination of gravity and one or more pumps 122. Similarly, the anolyte may be circulated through the anolyte reservoir 124 and the anode chamber 104 by a combination of gravity and one or more pumps 126.

[0069] Figure 2 A block diagram schematically depicts an exemplary electrodeposition system 200 that includes an electroplating unit 202. The electroplating unit 202 is Figure 1An example of the electroplating unit 102. The electroplating unit 202 includes an anode chamber 204 and a cathode chamber 206. The electroplating unit 202 also includes a cation exchange membrane 208 that defines a boundary between the anode chamber 204 and the cathode chamber 206. The cation exchange membrane 208 is an example of the ion exchange membrane 108. The substrate holder 210 is configured to support and position the substrate 212 such that the deposition surface of the substrate 212 is within the cathode chamber 206.

[0070] The anode chamber 204 includes an anolyte bath solution 216 with an anode 218 disposed therein. In this example, the anode 218 includes a copper metal anode. In other examples, the anode 218 may include another consumable anode or an inert anode. A voltage source 219 applies a voltage across the substrate 212 and the anode 218 to drive the flow of metal ions for deposition on the substrate 212.

[0071] The anolyte bath solution 216 is located in the anolyte circulation loop 220. The anolyte enters the anode chamber 204 through the inlet 222 and exits through the outlet 224. The anolyte circulation loop 220 includes a heater 226 (e.g., a heater / cooler) configured to adjust and / or maintain the temperature of the anolyte flowing through the anolyte circulation loop 220. The electroplating unit 202 also includes a fluid distribution system 230. The fluid distribution system 230 includes a membrane assembly 232 that includes a membrane frame 234 configured to support the ion exchange membrane 208. The fluid distribution system 230 also includes an HRVA 236 located between the membrane frame 234 and the substrate holder 210.

[0072] The fluid distribution system 230 supplies a catholyte bath solution 238 to the cathode chamber 206, and the catholyte bath solution 238 contains ionic copper (Cu 2+ ) to be deposited onto the substrate 212 acting as a cathode. The catholyte bath solution 238 is located in the catholyte circulation loop 240. The catholyte enters the cathode chamber 206 through the inlet 242 and exits through the outlet 244. The catholyte circulation loop 240 includes a heater 246 (e.g., a heater / cooler) configured to adjust and / or maintain the temperature of the catholyte flowing through the catholyte circulation loop 240.

[0073] For copper electroplating, in some examples, the anode 218 may include a copper block (e.g., a ball) or a copper plate. As mentioned above, in other examples, the anode 218 may include an inert anode. In the described example, the applied voltage causes the copper in the anode 218 to oxidize to Cu 2+ . The cation exchange membrane 208 allows Cu 2+ ions to flow from the anolyte bath solution 216 to the catholyte bath solution 238. The Cu 2+The ions replace at least some of the copper ions in catholyte bath 238 that were reduced to substrate 212 .

[0074] Heater 246 can be controlled to maintain catholyte bath 238 at a predetermined process temperature during the electroplating process. Heater 226 can also be controlled to maintain anolyte bath 216 at a predetermined process temperature during the electroplating process. The process temperature may include relatively low temperatures in some processes. For example, a process temperature in the range of 22°C-26°C may be used in some copper deposition processes.

[0075] As mentioned above, some electroplating conditions may increase the concentration of dissolved copper ions in the catholyte near the surface of the cation exchange membrane. The resulting concentration may exceed the solubility limit of the catholyte solvent (e.g., water) at the processing temperature. This may result in the formation of crystals on the cation exchange membrane. Figure 2 In the example, the Cu in the anolyte bath 216 2+ The ions pass through the cation exchange membrane 208 and into the catholyte bath 238. Thus, the catholyte just above the cation exchange membrane 208 contains ions from the catholyte in the catholyte bath 238 and additional Cu from the anolyte bath 216. 2+ When the plating current increases, the additional Cu 2+ The concentration of ions increases.

[0076] If there is not enough catholyte convection to remove excess Cu 2+ ions, the solution above the cation exchange membrane may precipitate solid copper salts on the cation exchange membrane. CuSO 4 May be the main component of copper salt precipitates. Catholytes containing copper may also contain chloride ions and sulfonic acid anions. These anions may also form copper precipitates. Metal salt precipitation may also occur in other electroplating chemistries. Examples include tin and tin-silver alloys. For tin-silver, example counter anions include methylsulfonic acid and organic acids. Precipitates may also occur for other electroplated metals, including cobalt, indium, and nickel.

[0077] The existence of the metal salt precipitate on the cation exchange membrane 208 may block the distribution of fluid transmission and electric current. Such a situation may be referred to as passivation. If the regional part or all of the cation exchange membrane is passivated, non-uniform current distribution may be caused. This may cause non-uniform metal plating on the substrate. In some examples, one or more sensors may be located in or near the electroplating unit 202 to monitor the situation and provide a non-uniform indication of the accumulation that may indicate the metal salt precipitate. Exemplary sensor comprises cathode current sensor array and / or one or more optical sensors.

[0078] Passive irrigation may not be sufficient to reduce catholyte stagnation at the cation exchange membrane 208. Therefore, the disclosed examples utilize an active irrigation system to avoid the risk of stagnation and metal salt precipitate formation.

[0079] The catholyte circulation loop 240 is operable to flow the catholyte across the surface of the HRVA 236 in a first direction. The direction is indicated by the arrow between the inlet 242 and the outlet 244. For example, some of the catholyte is delivered through a channel in the membrane frame 234 that leads to an inlet hole in a plate supporting the HRVA 236. This may be referred to as an under-flow HRVA. One or more outlet holes in such a plate may then couple the catholyte back to the catholyte circulation loop 240 on the opposite side via the outlet 244.

[0080] In this example, a plurality of flow barriers 248 extend between the membrane frame 234 and the HRVA 236 in a second direction transverse to the first direction. This configuration may be referred to as a flow focusing manifold. The flow barriers 248 may prevent flow from traveling under the HRVA 236. This may reduce the fluid pressure required for the catholyte to flow across the HRVA 236. This may help maintain or improve electroplating performance at the substrate 212.

[0081] In addition, the membrane frame 234 includes an inlet manifold 250 for receiving and distributing catholyte from the catholyte circulation loop 240. Some of the received catholyte may be directed across the HRVA 236 as described. At least some of the received catholyte may be transferred to a plurality of irrigation conduits 252 located between adjacent flow barriers 248.

[0082] Irrigation conduits 252 are depicted as being located between adjacent flow barriers 248. Each irrigation conduit 252 can be configured to receive catholyte from the catholyte circulation loop 240 and direct the catholyte toward the membrane assembly via a plurality of emitters (e.g., as indicated by arrows). The irrigation conduits 252 can thus provide a catholyte flow directed toward the cation exchange membrane 208, thereby irrigating the substrate-facing side of the cation exchange membrane 208.

[0083] Figure 3A cross-section of an exemplary membrane assembly 300 is shown. The membrane assembly 300 can be an example of the membrane assembly 232. The membrane assembly 300 includes: a membrane frame 302, an ion exchange membrane 304, and a HRVA 306. The HRVA 306 can be mounted to a surface (e.g., an upper surface) of the membrane frame 302. The ion exchange membrane 304 can be clamped or otherwise secured to the opposite side (e.g., the bottom surface) of the membrane frame 302 relative to the HRVA 306. In this example, the membrane frame 302 includes a grid structure that includes a plurality of gap openings 308 where the ion exchange membrane 304 is exposed to fluid on either side.

[0084] Flow barriers 310 are integral with the membrane frame 302. The flow barriers 310 extend transverse to the direction of fluid flow across the HRVA 306. The flow barriers 310 extend across the membrane frame 302. In this example, the flow barriers 310 are integrally formed with portions of the grid structure. For example, every other crossbar of the grid may extend from the membrane frame 302 toward the HRVA 306 to prevent the catholyte flow from flowing under the HRVA 306. In some examples, a seal is located between the flow barriers 310 and the HRVA 306.

[0085] Adjacent flow barriers 310 thus define opposing walls of segmented volumes 312. Flow barriers 310 include apertures 314 proximal to membrane frame 302. The term "proximal to membrane frame" may generally refer to a location closer to ion exchange membrane 304 than HRVA 306 when membrane assembly 300 is assembled. Apertures 314 fluidly couple adjacent segmented volumes 312. Apertures 314 increase irrigation of ion exchange membrane 304 by allowing some catholyte to flow across flow barriers 310 from high pressure (e.g., inlet) to low pressure (e.g., outlet) and between adjacent segmented volumes 312.

[0086] An irrigation conduit 316 extends centrally through each segmented volume 312 and operates to eject catholyte to irrigate the underlying exposed openings 308 of the ion exchange membrane 304. The irrigation conduit 316 may be constructed of a non-conductive material, such as a polymer or ceramic, to reduce any electric fields that may interfere with the electrodeposition process.

[0087] Each irrigation conduit 316 includes a plurality of emitters 318. In some examples, the emitters 318 direct the catholyte toward the grid structure of the membrane frame 302. For example, the emitters 318 may be designed to emit the catholyte toward the intersection of the grid structure. However, other configurations are also contemplated. In some examples, the emitters 318 direct the catholyte flow perpendicular to the surface of the corresponding irrigation conduit. However, some or all of the emitters may have directional outputs, such as nozzles. This may allow for advantageous placement of the emitters 318, adjustable emission directions, and / or emission directed to areas where crystal growth may develop.

[0088] Figure 4 A cutaway exploded view of an exemplary membrane assembly 400 of an electrodeposition cell is shown, the electrodeposition cell comprising a fluid distribution system. The membrane assembly 400 can be an example of the membrane assemblies 232 and 300. The membrane assembly 400 comprises a membrane frame 402, which is configured to support an ion exchange membrane 404. The membrane frame 402 comprises: a plurality of flow barriers 406; and an inlet manifold 408, which is configured to receive a catholyte from a catholyte circulation loop.

[0089] The distribution manifold 410 is configured to be connected to the membrane frame 402 via the outer groove 411 to be integrated with the membrane frame 402. The distribution manifold 410 includes a plurality of irrigation conduits 412, each of which includes a number of emitters 414. The distribution manifold 410 can be fluidly coupled to the catholyte circulation loop via the inlet manifold 408. In some examples, the membrane frame 402 can be configured to accommodate the fluid inlet of the distribution manifold 410.

[0090] When in place, the distribution manifold 410 can be fluidly coupled to the inlet manifold 408 of the membrane frame 402 via two or more inlet ports. In this example, three inlet ports 415, 416, and 417 are shown arranged around the perimeter of the membrane frame 402. The inlet ports 415, 416, and 417 extend from the inlet manifold 408 to the distribution manifold 410, thereby delivering the catholyte to the distribution manifold 410.

[0091] In some examples, additional inlet ports may be included, although some or all of these ports may be capable of being plugged, such as by threaded bolts or crimped bolts. In this way, the fluid pressure profile of the membrane assembly 400 can be adjusted. Such adjustments can be dynamically performed during maintenance or during installation through controllable valves. For example, different electroplating applications may require different flow rates through the cathode electrolyte circulation loop. Different substrate positioning relative to the HRVA may also affect the flow and pressure through the distribution manifold 410.

[0092] In some examples, the manifold allows approximately equal flow to be output from each emitter of the irrigation conduit 412, including the emitters located farthest from the inlet port. For a given flow rate, the size of the emitters allows for an appropriately reduced pressure drop between the inlet and the far end of the manifold relative to the size of the channel. This consistent pressure produces a consistent flow through the emitters.

[0093] An electrical shield (not shown) may also be fitted in the outer slot 411. The thickness of such an electrical shield affects the electroplating on the substrate. By using a thinner distribution manifold, e.g. Figure 6BFurther described, the backside plug-in can be made relatively thick. In such a configuration, it can be advantageous to have a larger inlet flow rate. The three depicted inlet ports can provide an appropriate flow rate.

[0094] Figure 5 A exploded view 500 of the distribution manifold 410 and associated gasket 510 of the depicted Figure 4 membrane assembly is shown. The distribution manifold 410 includes a face toward the HRVA component (piece) 515 and a face toward the membrane component 517. The distribution manifold 410 is shown as including a pair of outlet ports 522 and 523 opposite the inlet ports 415, 416, and 417. The outlet ports 522 and 523 can include circular ports, as shown, and / or elongated ports, such as arcuate ones extending around the length of the distribution manifold.

[0095] In this example, the outlet ports 522 and 523 are set into the face toward the membrane component 517 and the gasket 510. The emitters 525 are arranged along the transverse component of the face toward the membrane component 517.

[0096] The gasket 510 can be used to create a seal when mounting the distribution manifold 410 to the membrane frame 402. Although shown as having a similar coverage area to the distribution manifold 410, the gasket seals the inlet ports 415, 416, and 417 and the outlet ports 522 and 523. The gasket 510 can thus have a different shape in other examples while accommodating these ports. The gasket 510 can be made of an elastic material. Additionally, the gasket 510 can be joined to the face toward the membrane component 517.

[0097] Fig. 6A and 6B Two exemplary structures of the distribution manifold and gasket assembly are shown. In different examples, the distribution manifold 410 can be set or 3D printed as a single component or an assembly of interlocking components. In these examples, two parts with equal coverage areas overlap and are joined together to form the distribution manifold. For example, the face toward the HRVA component and the face toward the membrane component can be set and then solvent joined together.

[0098] The distribution manifold and gasket assembly 600 includes: a face toward the HRVA component 602, a face toward the membrane component 604, and a gasket 606. An inlet port 608 is shown in the gasket 606. The portions of the face toward the HRVA component 602 and the face toward the membrane component 604 create an irrigation conduit 610 that has emitters 612 formed in the face toward the membrane component 604. In this example, both the face toward the HRVA component 602 and the face toward the membrane component 604 have a depth and can be set to form a relatively thick structure of the distribution manifold.

[0099] The distribution manifold and gasket assembly 620 includes: a HRVA-facing member 622, a membrane-facing member 624, and a gasket 626. An inlet port 628 is shown in the gasket 626. Portions of the HRVA-facing member 622 and the membrane-facing member 624 create an irrigation conduit 630 having an emitter 632 formed in the membrane-facing member 624. In this example, the membrane-facing member 624 is flat with openings provided for the emitter, the inlet port, and the outlet port.

[0100] Figure 7 and 8 An exemplary membrane frame 700 is depicted. The membrane frame 700 comprises a lattice structure 702 comprising a plurality of openings 704 that expose an underlying cation exchange membrane. Thus, the membrane frame 700 may be an example of the membrane frame 300.

[0101] The membrane frame 700 includes a plurality of flow barriers 706 extending from alternating grid lines in a direction transverse to the direction of the catholyte flow (as indicated by the arrows) across the HRVA. The grid structure adjusts the positioning of the flow barriers in a manner that helps avoid disrupting the conductivity across the cation exchange membrane. The membrane frame 700 includes an inlet port 708. The inlet port 708 receives catholyte from the catholyte circulation loop. The membrane frame 700 also includes an outlet port 710. The outlet port 710 directs the catholyte back into the catholyte circulation loop.

[0102] like Figure 3 As shown in FIG. 1 , the irrigation conduits of the distribution manifold can be positioned in the segmented volumes between adjacent flow barriers. Figure 8 800. Irrigation conduits 802, 804, and 806 are alternated with flow barriers 706. Each irrigation conduit includes a plurality of emitters 810, represented by circles. In some examples, the emission can be directed to adjacent portions of the grid structure 702, thereby agitating the nearby catholyte, without directly directing the catholyte to the ion exchange membrane.

[0103] The emitters 810 are positioned to discharge the catholyte toward the intersections of the grid structure 702. In this example, the emitters are positioned to discharge the catholyte toward alternating intersections of the grid structure. In this way, the irrigation conduits form a collectively uniform distribution of the catholyte across the membrane frame 700 between the flow barriers 706.

[0104] As shown at 820, the emitter 810 discharges the catholyte in the form of a fluid jet, which strikes the intersection 822 of the grid structure 702, causing the ejected catholyte to be distributed to the adjacent openings 704. Due to the presence of the flow barrier 706, multiple segmented volumes are formed in the membrane assembly. Therefore, the fluid discharged from the emitter 810 does not affect the membrane irrigation in the adjacent segmented volume. The distribution manifold can therefore be configured with multiple conduits, one or more conduits per segmented volume, so that each segmented volume is irrigated. This ensures appropriate uniform irrigation across the entire membrane surface.

[0105] Fig. 9 Shown is an exemplary curve depicting the inlet pressure (e.g., pounds per square inch) in the range of the total flow rate of the electroplating pump (e.g., liters per minute) for different plating gap distances. Curve 900 is shown in the inlet pressure when there is no distribution manifold involved, and curve 910 shows the inlet pressure when there is a distribution manifold involved. Each curve represents the relationship of the pressure to flow rate of the plating gap (e.g., between the HRVA top and the substrate bottom) of the following conditions: the plating gap range is from the reference position to the distance increased (from the reference arbitrary unit: +1.5, +2.5, +3.5), and the situation that the substrate does not participate (e.g., no electroplating).

[0106] For all plating gaps, the trend of the inlet pressure is similar whether the distribution manifold is involved (curve 910) or not involved (curve 900). Therefore, the performance of the device with a distribution manifold is likely to be similar in the case of electrodeposition over a similar pressure range and plating gap range as the model without such a distribution manifold.

[0107] With such flow / pressure data it is also possible to simulate the pressure of the catholyte discharged from the manifold emitters. In one example, emitter holes with diameters on the order of 0.025-0.05 inches were simulated. At some flow rates, holes with a diameter of about 0.035 inches allowed flow balance between the various emitters, while larger holes produced unbalanced flow and smaller holes caused choked flow. However, performance may vary based on factors such as the size of the distribution manifold.

[0108] Fig.10 A flow chart depicting an exemplary method 1000 of irrigating an ion exchange membrane in an electrodeposition system is shown. The method 1000 can be performed by any suitable electrodeposition system (eg, electrodeposition system 200) that includes a fluid distribution system.

[0109] At 1010, method 1000 includes flowing a catholyte across a high resistance virtual anode (HRVA) in a first direction. The HRVA is separated from an ion exchange membrane by a membrane frame. In addition, the membrane frame includes a plurality of flow barriers extending from the membrane frame to the HRVA in a second direction transverse to the first direction. The membrane frame may be configured to receive catholyte from a catholyte circulation loop into an inlet manifold. In addition, the membrane frame is configured to direct the catholyte in the first direction.

[0110] At 1020, method 1000 includes transferring some of the catholyte to a distribution manifold, which includes irrigation conduits located between adjacent flow barriers. Each irrigation conduit is configured to direct the catholyte to the membrane frame via a plurality of emitters. In some such examples, transferring the catholyte to the distribution manifold includes: transferring the catholyte via two or more inlet ports of an inlet manifold that is fluidly coupled to the membrane frame. In such examples, method 1000 may further include transferring the catholyte to one or more outlet ports of the distribution manifold. The one or more outlet ports are located opposite the inlet ports. In some such examples, directing the catholyte to the membrane frame via the plurality of emitters includes: draining the catholyte toward an intersection of a grid structure of the membrane frame. The grid structure defines a plurality of openings that expose the ion exchange membrane. In some such examples, as Figure 8 As shown in , discharging the cathode electrolyte toward the intersections of the grid structure includes: discharging the cathode electrolyte toward alternating intersections of the grid structure.

[0111] It should be understood that the configuration and / or method described herein are exemplary in nature, and these specific embodiments or exemplary should not be considered as restrictive, because many variations are possible. The specific routine or method described herein can represent one or more of any number of processing strategies. Therefore, the various actions shown and / or described can be performed in the order shown and / or described, in other orders, in parallel or omitted. Equally, the order of the above-mentioned processing can be changed.

[0112] The subject matter of the present disclosure includes all novel and nonobvious combinations and subcombinations of the various processes, systems and configurations, and other features, functions, acts, and / or properties disclosed herein, as well as any and all equivalents thereof.

Claims

1. An electrodeposition system, comprising: A fluid distribution system comprising: a membrane assembly comprising a membrane frame configured to support an ion exchange membrane that defines a boundary of a cathode chamber; a high resistance virtual anode (HRVA) located between the membrane frame and the substrate holder; a catholyte circulation loop operable to flow catholyte in a first direction across a surface of the HRVA facing the substrate holder; and a plurality of flow barriers extending between the membrane frame and the HRVA along a second direction transverse to the first direction; as well as Irrigation conduits are located between adjacent flow barriers, each of the irrigation conduits being configured to receive catholyte from the catholyte circulation loop and direct the catholyte to the membrane modules via a plurality of emitters. 2 . The electrodeposition system of claim 1 , wherein the flow barrier is integrated with the membrane frame.

3. The electrodeposition system of claim 1, wherein adjacent flow barriers define opposing walls of a segmented volume, and wherein the flow barriers include holes proximate the membrane frame, the holes fluidly coupling adjacent segmented volumes.

4. The electrodeposition system of claim 1, wherein the irrigation conduits are formed in a distribution manifold that is fluidly coupled to the catholyte circulation loop.

5. The electrodeposition system of claim 4, wherein the distribution manifold is fluidly coupled to the catholyte circulation loop via an inlet manifold of the membrane frame.

6. The electrodeposition system of claim 5, wherein the distribution manifold is fluidly coupled to the inlet manifold of the membrane frame via two or more inlet ports.

7. The electrodeposition system of claim 6, wherein the distribution manifold comprises one or more outlet ports opposite the two or more inlet ports.

8. The electrodeposition system of claim 1, wherein the membrane frame comprises a grid structure comprising a plurality of openings, the openings exposing the ion exchange membrane.

9. The electrodeposition system of claim 8, wherein the emitters are positioned to discharge catholyte toward intersections of the grid structure.

10. The electrodeposition system of claim 9, wherein the emitters are positioned to discharge catholyte toward alternating intersections of the grid structure.

11. A fluid distribution system for an electrodeposition system, the fluid distribution system comprising: a membrane frame configured to support an ion exchange membrane, the membrane frame comprising a lattice structure and a plurality of flow barriers extending from the lattice structure; and A plurality of irrigation conduits, each of the plurality of irrigation conduits being configured to be positioned between adjacent flow barriers to receive catholyte from a catholyte circulation loop and to direct the catholyte to the membrane assembly via a plurality of emitters.

12. The fluid distribution system of claim 11, wherein the flow barrier is integral with the membrane frame.

13. The fluid distribution system of claim 12, wherein the irrigation conduits are formed in a distribution manifold that is fluidly coupled to an inlet manifold of the membrane frame via two or more inlet ports.

14. The fluid distribution system of claim 13, wherein the distribution manifold comprises one or more outlet ports opposite the two or more inlet ports.

15. The fluid distribution system of claim 11, wherein the grid structure includes a plurality of openings that expose the ion exchange membrane, and wherein the emitters are positioned to discharge catholyte toward intersections of the grid structure.

16. The fluid distribution system of claim 15, wherein the emitters are positioned to discharge catholyte toward alternating intersections of the grid structure.

17. A method for irrigating an ion exchange membrane in an electrodeposition system, comprising: flowing a catholyte in a first direction across a high resistance virtual anode (HRVA) separated from the ion exchange membrane by a membrane frame comprising a plurality of flow barriers extending from the membrane frame to the HRVA in a second direction transverse to the first direction; and Some of the catholyte is transferred to a distribution manifold comprising irrigation conduits located between adjacent flow barriers, each irrigation conduit being configured to direct catholyte toward the membrane frames via a plurality of emitters.

18. A method according to claim 17, wherein transferring the cathode electrolyte to the distribution manifold includes: transferring the cathode electrolyte via two or more inlet ports of an inlet manifold that is fluidically coupled to the membrane frame, and wherein the method further includes transferring the cathode electrolyte to one or more outlet ports of the distribution manifold, wherein the one or more outlet ports are located opposite the inlet ports.

19. The method of claim 17, wherein directing catholyte to the membrane frame via a plurality of emitters comprises discharging catholyte toward intersections of a lattice structure of the membrane frame, the lattice structure comprising a plurality of openings exposing the ion exchange membrane.

20. The method of claim 19, wherein discharging catholyte toward intersections of the grid structure comprises discharging catholyte toward alternating intersections of the grid structure.

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