Cleaning components and methods in a plating system

Systems for cleaning electroplating system components may include a seal cleaning assembly incorporated with an electroplating system. The seal cleaning assembly may include an arm pivotable between a first position and a second position. The arm may be rotatable about a central axis of the arm. The seal cleaning assembly may also include a cleaning head including a bracket portion coupled with a distal portion of the arm. The cleaning head may be characterized by a front portion formed to interface with a seal of the electroplating apparatus. The cleaning head may define a trench along the front portion, and the cleaning head may define a plurality of fluid channels through the cleaning head, each fluid channel of the plurality of fluid channels fluidly accessing a backside of the trench.

TECHNICAL FIELD

The present technology relates to cleaning operations in semiconductor processing. More specifically, the present technology relates to systems and methods that perform in situ cleaning for electroplating systems.

BACKGROUND

Integrated circuits are made possible by processes which produce intricately patterned material layers on substrate surfaces. After formation, etching, and other processing on a substrate, metal or other conductive materials are often deposited or formed to provide the electrical connections between components. Because this metallization may be performed after many manufacturing operations, problems caused during the metallization may create expensive waste substrates or wafers. One common problem is non-uniform formation of metal across a substrate surface.

Uniformity issues during metallization may be caused from a number of situations related to the process or the equipment. One example is plating on components of the chamber that are or become conductive, and which may cause local loss of metal on the substrate. Material may be plated on the contact ring, contact seal, or any other component that may be within the system. This errant formation may limit the amount of plating on the substrate, which can lead to insufficient plating, increased cost, and device failure.

SUMMARY

The present technology may include systems and methods for cleaning electroplating system components, which may include a seal cleaning assembly incorporated with an electroplating system. The seal cleaning assembly may include an arm pivotable between a first position and a second position. The arm may be rotatable about a central axis of the arm. The seal cleaning assembly may also include a cleaning head including a bracket portion coupled with a distal portion of the arm. The cleaning head may be characterized by a front portion formed to interface with a seal of the electroplating apparatus. The cleaning head may define a trench along the front portion, and the cleaning head may define a plurality of fluid channels through the cleaning head, each fluid channel of the plurality of fluid channels fluidly accessing a backside of the trench.

In some embodiments the front portion of the cleaning head may be at least partially characterized by an arcuate profile configured to accommodate an annular seal. The cleaning head may also include a contact pin at least partially extending through the trench and configured to be in direct contact with the seal. The cleaning head may also include a clearance pin at least partially extending through the trench and configured to define a gap between the clearance pin and the seal when the contact pin is in direct contact with the seal. The plurality of fluid channels of the cleaning head may include a first channel fluidly accessing a first position along the trench, and may include a second channel fluidly accessing a second position along the trench radially offset from the first position in a direction of rotation of the seal. The clearance pin may be positioned between the first position and the second position. In some embodiments the cleaning head may be or include a hydrophobic material.

Embodiments of the present technology additionally encompass electroplating systems that may include a system head having a rotor. The system head may be configured to hold a substrate for processing. The systems may include a seal positioned on the rotor. The systems may include a head lifter coupled with the system head and configured to position the system head. The systems may also include a seal cleaning assembly. The seal cleaning assembly may include an arm pivotable between a first position and a second position where a distal portion of the arm may be vertically aligned with an interior region of the system head. The arm may be rotatable about a central axis of the arm. The seal cleaning assembly may also include a cleaning head including a bracket portion coupled with a distal portion of the arm. The cleaning head may be characterized by a front portion formed to interface with an interior surface of the seal. The cleaning head may define a trench along the front portion, and the cleaning head may define a plurality of fluid channels through the cleaning head. Each fluid channel of the plurality of fluid channels may fluidly access a backside of the trench.

In some embodiments, the arm may be located in the second position, and the distal portion of the arm may be configured to rotate the cleaning head from a retracted position into direct contact with the seal. The system may include a torque-controlled motor configured to drive the arm and maintain contact between the cleaning head and the seal while the rotor rotates the seal across the cleaning head. The seal may be characterized by an annular form, and the front portion of the cleaning head may be at least partially characterized by an arcuate profile configured to accommodate an inner annular sidewall of the seal. The cleaning head may also include a contact pin at least partially extending through the trench and configured to be in direct contact with the seal during a cleaning operation. The cleaning head may also include a clearance pin at least partially extending through the trench and configured to define a gap between the clearance pin and the seal when the contact pin is in direct contact with the seal. The plurality of fluid channels may include a first channel fluidly accessing a first position along the trench and a second channel fluidly accessing a second position along the trench radially offset from the first position in a direction of rotation of the seal. The clearance pin may be positioned between the first position and the second position. The system may include a fluid delivery tube extending along the arm and configured to provide a fluid to the first channel. The system may also include a fluid removal tube extending along the arm and configured to remove the fluid from the second channel. In some embodiments a vacuum may be maintained through the fluid removal tube during operation.

Embodiments of the present technology may also encompass methods of cleaning an electroplating system contact seal. The methods may include delivering an acidic solution in a first fluid channel of a cleaning head. The cleaning head may be positioned to physically contact the electroplating system contact seal. The methods may include rotating the electroplating system contact seal across the cleaning head. The methods may also include extracting the acidic solution from the cleaning head through a second fluid channel radially offset from the first fluid channel in a direction of rotation of the electroplating system contact seal. In some embodiments the acidic solution may be substantially maintained within a volume defined in part by an inner surface of the electroplating system contact seal, a trench formed within a front portion of the cleaning head, and a contact pin at least partially extending through the trench proximate a leading edge of the cleaning head in a direction of rotation of the electroplating system contact seal.

Such technology may provide numerous benefits over conventional technology. For example, the present technology may reduce cleaning times by allowing in situ cleaning of a contact seal to be performed. Additionally, the apparatus used may facilitate an improved cleaning of the contact seal without compromising other system components with the cleaning solution. These and other embodiments, along with many of their advantages and features, are described in more detail in conjunction with the below description and attached figures.

DETAILED DESCRIPTION

Various operations in semiconductor manufacturing and processing are performed to produce vast arrays of features across a substrate. As layers of semiconductors are formed, vias, trenches, and other pathways are produced within the structure. These features may then be filled with a conductive or metal material that allows electricity to conduct through the device from layer to layer. As device features continue to shrink in size, so too does the amount of metal providing conductive pathways through the substrate. As the amount of metal is reduced, the quality and uniformity of the fill may become more critical to ensure adequate electrical conductivity through the device. Accordingly, manufacturing may attempt to reduce or remove imperfections and discontinuities in the pathways.

Electroplating operations may be performed to provide conductive material into vias and other features on a substrate. Electroplating utilizes an electrolyte bath containing ions of the conductive material to electrochemically deposit the conductive material onto the substrate and into the features defined on the substrate. The substrate on which metal is being plated operates as the cathode. An electrical contact, such as a ring or pins, may allow the current to flow through the system. This contact may be protected from the electrolyte by a seal, which may prevent metal from being plated on other conductive components. The seal is often a non-conductive material, however, over time the seal may become conductive due to residues formed on the seal during plating operations. When sufficiently conductive, plating may occur on the seal, which may reduce local plating on the substrate, causing uniformity issues, which may result in scrapped substrates or wafers.

Conventional technologies often halt operations between wafers to clean residues from this seal. The system may be partially disassembled, and the seal may be cleaned and scrubbed manually before being replaced in the tool. This process is time consuming, and abrasive scrubbing may further roughen the seal surfaces increasing the amount of conductive residue that may remain on the seal during processing.

The present technology overcomes these issues by incorporating a cleaning system that may perform an in situ clean of the seal. The system may include a nozzle or head that may be extended against the seal, and a cleaning solution may be flowed against the seal to remove any residues. By utilizing cleaning systems according to the present technology, cleaning may be performed more easily, and surface damage to the seal may be limited or reduced. After describing an exemplary chamber for which embodiments of the present technology may be performed, the remaining disclosure will discuss aspects of the systems and processes of the present technology.

FIG. 1shows a schematic perspective view of an electroplating system20for which methods and cleaning systems may be utilized and practiced according to embodiments of the present technology. Electroplating system20illustrates an exemplary electroplating system including a system head22and a bowl26. During electroplating operations, a wafer may be clamped to the system head22, inverted, and extended into bowl26to perform an electroplating operation. Electroplating system20may include a head lifter24, which may be configured to both raise and rotate the head22, or otherwise position the head within the system. The head and bowl may be attached to a deck plate28or other structure that may be part of a larger system incorporating multiple electroplating systems20, and which may share electrolyte and other materials. Rotor34may allow a substrate clamped to the head to be rotated within the bowl, or outside the bowl in different operations. The rotor may include a contact ring40, which may provide the conductive contact with the substrate.FIG. 1illustrates an electroplating chamber that may include components to be cleaned directly on the platform. It is to be understood that other configurations are possible, including platforms on which the head is moved to an additional module and seal or other component cleaning is performed. Additionally, one or more components, such as a seal ring may be removed from a chamber and placed in a maintenance system or cleaning system for cleaning. Any number of other operations may be performed that provide or expose a component for cleaning.

Turning toFIG. 2is shown a partial cross-sectional view of electroplating system20. A motor38included within the head may allow rotation of the contact ring40, as well as a contact seal50, which may seal against the substrate. This seal may allow isolation of the contact ring40from the electrolyte during operation, which may prevent plating on the contact ring. The seal may be made of an insulative material, and may be made of materials configured to limit interaction with the electrolyte. For example, the seal material may include a number of polymers including elastomers, and may include fluoropolymers, such as fluoroelastomers, including any FKM materials including Type 1, Type 2, Type 3, Type 4, and Type 5 FKM materials. The materials may also include perfluoroelastomers including any FFKM materials, as well as tetrafluoroethylene/propylene rubbers or FEPM. Seal materials may also include thermoplastic elastomers, including thermoplastic vulcanizates, and elastomers with additional moieties, such as styrene ethylene butylene styrene, as well as materials developed from polyolefins or other plastics. The seal may also include any other materials that may be compatible with electroplating systems and electrolytes.

As previously explained, residues may form on the seal during electroplating operations. In some embodiments of the present technology, subsequent a plating operation, the substrate may be removed, and the seal may be cleaned. The seal may be cleaned on the same platform on which the bowl resides, or the head may be repositioned to a separate module either associated with or connected to system20. Head22may be inverted, and a seal cleaning assembly may be used to clean the seal while the seal is still connected with the head.FIG. 3illustrates a schematic front perspective view of seal cleaning assembly300as may be used in embodiments of the present technology. With the substrate removed, and the head22inverted, seal cleaning assembly300may be positioned within a cavity of the head, and used to clean the interior of the seal, which may have plating residues on the surface. It is to be understood that inversion of the head may not be critical, and the present systems may be operated to accommodate a seal in any orientation.

As illustrated, seal cleaning assembly300may include an arm305, and a cleaning head310. Arm305may be a swing arm or other device associated with the electroplating system or a maintenance system for the head, and may be pivotable between a number of positions including a first position, which may be retracted, and a second position, which may be an operational position and may position a distal portion of arm305, with which cleaning head310may be coupled, at a location that may be vertically aligned with an interior region of the system head22. Arm305may also be rotatable about a central axis of the arm, which may allow the cleaning head to be raised and lowered to an operational position in which the cleaning head may be in contact with a seal. Arm305may be an L-shaped or otherwise retractable or extendable arm, and may be coupled with a torque-controlled motor, which may be incorporated with the arm or connected with the arm. The torque-controlled motor may drive the arm between the first and second positions, and may also be configured to maintain contact between the cleaning head and the seal to be cleaned.

Arm305may also include one or more fluid delivery tubes307aor fluid removal tubes307bthat may extend along the arm. The tubes may be coupled with one or more reservoirs or other materials that may be used for the cleaning operation, and may couple or fluidly connect with cleaning head310. For example, fluid delivery tube307amay provide one or more cleaning solutions into the cleaning head, while fluid removal tube307bmay remove the cleaning solution subsequent interaction with the seal to be cleaned. Cleaning head310may allow the cleaning solution to be delivered to and removed from the seal without contacting other chamber components, dripping, or otherwise interacting with system head22. The seal contact and cleaning operations will be described in more detail below.

Cleaning head310may be multiple components coupled together, or may be a single piece machined design that incorporates one or more aspects in the design. Cleaning head310may include a bracket portion312, by which the cleaning head310may be coupled with arm305, such as with a distal portion of arm305. The bracket portion312may be coupled with the head rigidly with any number of components including fastening components, adhesive, or the bracket portion may include a form configured to accommodate snap-fitting the cleaning head on the arm. Any number of aspects of the arm or the cleaning head bracket portion may be adjusted to provide a coupling between the components.

A front portion314of cleaning head310may extend from bracket portion312in a first direction, and a back portion316of cleaning head310may extend from bracket portion312in a second direction opposite the front portion. Front portion314may be formed to interface with a seal of the electroplating system head. For example, the contact seal may be an annular component, and thus may be characterized by a curved profile along the inner and outer surfaces. Accordingly, front portion314may be at least partially characterized by an arcuate profile configured to accommodate the curvature of the seal. This may allow an improved contact to be afforded between the components to reduce the opportunity for fluid leaks or dripping.

Cleaning head310may define a trench318along the front portion314. Trench318may be defined by an upper sidewall320and a lower sidewall322, and may face the seal to be cleaned. One or both of the upper sidewall320and the lower sidewall322may exhibit the arcuate profile in embodiments. For example, in some embodiments lower sidewall322may exhibit an arcuate profile along the front portion314of the cleaning head310. The lower sidewall may be characterized by a curvature equivalent to the curvature of the seal to limit any fluid leakage out of the trench through a space formed between the components.

Cleaning head310may be made of any number of materials or combinations of materials. In some embodiments, the cleaning head310may include a polymeric material that may be resistant to damage from cleaning solutions that may be used. For example, as will be explained in relation to the operational method below, the cleaning solutions may include an acidic solution in some embodiments. Accordingly, cleaning head310may include materials that are resistant to acidic solutions that may flow through the cleaning head. Additionally, water, either in the acidic solutions or with a separate delivery, may be flowed through the cleaning head310. In some embodiments cleaning head310may include a hydrophobic material that may resist wetting by the cleaning fluids, and may facilitate movement and removal of the cleaning fluids through the cleaning head310. By utilizing hydrophobic materials, the cleaning fluid may better fill the volume of the trench because it may be repelled from the cleaning head forming a high contact angle of the cleaning solution on the surfaces of the cleaning head, such as greater than 90°. This may ensure that the entire surface of the seal is contacted by the cleaning solution. For example, cleaning head310may be or include a similar or identical material to the seal to be cleaned, and may be any of the materials previously described. Cleaning head310may also be or include a fluoropolymer, including polyvinyl fluorides, fluoroethylene compounds including polytetrafluoroethylene, fluoropropylene compounds, and other compounds that may resist any materials used in electroplating or in the cleaning operations to be discussed.

FIG. 4shows a schematic perspective view of cleaning head310according to some embodiments of the present technology.FIG. 4may further illustrate back portion316of cleaning head310, and may illustrate fluid delivery ports324. As previously explained, fluid tubes307may extend along arm305and may be fluidly connected with cleaning head310. The tubes may be fluidly coupled with the cleaning head310via the fluid delivery ports324, defined or positioned in back portion316of the cleaning head. Three fluid delivery ports324are illustrated, although depending on the size and configuration of the cleaning assembly, any number of fluid delivery ports324may be included with the system. The fluid delivery ports may access trench318, such as a backside of trench318as will be shown below, and may be used to deliver cleaning solutions to the trench, or may be used to retrieve cleaning solutions from the trench. For example, in one embodiment included for illustration of possible configurations encompassed by the technology, fluid delivery port324amay be fluidly coupled with fluid delivery tube307a, and fluid delivery ports324b,324cmay be fluidly coupled with two fluid removal tubes307b. Any other configuration may also be accommodated by the cleaning assembly as would be understood by the skilled artisan.

FIG. 5shows a schematic exemplary apparatus for positioning a cleaning head according to some embodiments of the present technology. The apparatus illustrated may include a base303within which the torque-controlled motor may be connected. Coupled with base303may be arm305, with which cleaning head310may be coupled at a distal location. As previously described, base303may be operable to pivot or swing arm305allowing cleaning head310to be positioned relative to a seal or other device to be cleaned. Cleaning head310may be maintained in a retracted or withdrawn position during operation of base303, which may facilitate positioning cleaning head310, while limiting the opportunity of cleaning head310to contact the seal or other components. By maintaining cleaning head310in a downward facing position recessed upwards, cleaning head310may be passed over a seal to be cleaned before being positioned in contact with the seal.

FIG. 6shows a schematic exemplary apparatus for positioning a cleaning head according to some embodiments of the present technology. Once cleaning head310has been swung into an interior region of the seal, arm305may rotate to position cleaning head310in an operational position in which it may contact a seal or other component to be cleaned. Although in some embodiments, arm305may rotate in either direction to operationally position cleaning head310, in some embodiments, arm305may swing clockwise to provide an amount of compression of the cleaning head310against the seal.FIGS. 5-6illustrate one possible system for delivering cleaning head310to a seal or component to be cleaned, but it is to be understood that any system may be used to pivot, rotate, or otherwise position cleaning head310against a seal to be cleaned.

Previously describedFIG. 4additionally illustrates that upper sidewall320may extend laterally beyond an outer edge of lower sidewall322in some embodiments. For example, when engaged with a seal, as will be shown below, upper sidewall320may extend beyond an inner wall of the seal, such that the seal may at least partially reside within trench318during cleaning.FIG. 7illustrates a partial cross-sectional view of cleaning head310in operation according to some embodiments of the present technology. The cross section may be through trench318, such as just below upper sidewall320, for example. As illustrated, and shown in the cross-section, the cleaning head310may define a plurality of fluid channels326through the cleaning head. Each fluid channel326may fluidly access a backside of trench318. Fluid channels326may extend to the backside of cleaning head310and be accessed from fluid delivery ports324. Accordingly, in some embodiments the number of fluid delivery ports may be equivalent to the number of fluid delivery channels. The fluid delivery channels may include a larger diameter portion and a smaller diameter portion as illustrated, with the smaller diameter portion being positioned between the trench318and the larger diameter portions. The adjustment in channel diameter may further facilitate fluid movement through the cleaning head.

The cleaning head may include one or more contact pins that may interact with the seal to be cleaned. As illustrated, cleaning head310may contact seal510on contact pin328and contact pin330. In operation, the system head rotor may rotate seal510across cleaning head310. The direction of rotation as illustrated may begin at a leading edge332of cleaning head310and extend laterally or radially along the cleaning head to trailing edge334. Contact pin328may at least partially extend through trench318, and may be positioned vertically through front portion314of cleaning head310. Contact pin328may be positioned proximate leading edge332of cleaning head310. The contact pin328may be configured to be in direct contact with seal510during a cleaning operation. Additionally, contact pin330may be identical to contact pin328, and may be positioned proximate trailing edge334of cleaning head310in the direction of rotation of seal510across the cleaning head. By having the contact pins extend only partially within trench318in some embodiments, the seal may at least partially recess within the trench both above and below the seal. Accordingly, a cleaning volume may be defined within trench318between the first contact pin328, the seal510, and the second contact pin330. This volume may be configured to maintain cleaning fluid delivered through the fluid channels of the cleaning head to limit or prevent any leakage from the cleaning head.

Cleaning head310may also include a clearance pin336positioned between the first contact pin328and the second contact pin330. Clearance pin336may at least partially extend through the trench318similar to the contact pins. Unlike the contact pins, clearance pin336may not contact seal510in some embodiments. Clearance pin336may instead define a gap between the clearance pin and the seal when the contact pins are in direct contact with the seal510. Consequently, clearance pin336may facilitate contact between a delivered cleaning fluid and the seal to ensure complete wetting of the seal during the seal rotation. As previously described, the components of cleaning head310may be hydrophobic, and thus depending on the gap distance between the trench and the seal, cleaning fluid may flow from a fluid delivery channel to a fluid removal channel without contacting the seal, or intermittently contacting the seal.

By including a clearance pin336, a reduced gap may be maintained that may be utilized to ensure contact entirely along the surface of the seal as it rotates across the cleaning head. In some embodiments, the gap may be less than or about 1 cm, and may be less than or about 9 mm, less than or about 8 mm, less than or about 7 mm, less than or about 6 mm, less than or about 5 mm, less than or about 4 mm, less than or about 3 mm, less than or about 2 mm, less than or about 1 mm, less than or about 0.5 mm, less than or about 0.2 mm, or less, depending on the size of the system, and surfaces to be cleaned. Contact pins328,330and clearance pin336may be similar or different materials from the seal or cleaning head, and may be or include any of the materials previously described. The pins may be common plastics including polyethylene, or any other long chain polymeric material, which may provide low friction or other beneficial properties, such as impact strength for when the cleaning head impacts the seal. Additionally, the pins may include any other polymer that may resist abrasion as the contact pins may be in direct contact with the seal, although the material may be compatible with the seal material to limit damage to the seal. Each of the pins may also be accessible from below the cleaning head allowing replacement if necessary.

The clearance pin336may be positioned within the cleaning head between inlet channels and outlet channels for the cleaning fluid. For example, as illustrated, first fluid channel326amay extend inward of contact pin328and into trench318at a first position. Second fluid channel326b, as well as third fluid channel326c, may fluidly access a second position, and third position respectively, along the trench radially or laterally offset from the first position in a direction of rotation of the seal. Clearance pin336may be positioned between the first fluid channel and the second fluid channel, and may be positioned at least partially within the trench between the first position and the second position.

A cleaning solution may be flowed or pumped into first fluid channel326a, such as by delivering the cleaning solution through fluid delivery tube307ato the first delivery port in the cleaning head310. Second fluid channel326b, as well as third fluid channel326c, may be used to retrieve the cleaning solution after it has contacted and interacted with seal510about clearance pin336. The second fluid channel and third fluid channel may be coupled through the fluid removal tubes with a vacuum system, such as an aspirator, which may allow a suction action to be performed to draw the cleaning fluid from the trench318and from the cleaning head310. The seal may be rotated during the flow of cleaning solution to enable the entire seal to be cleaned on one or more surfaces. As mentioned previously, a torque-controlled motor may be coupled with the arm on which the cleaning head is coupled, and may ensure the cleaning head maintains contact with the seal all along the seal as it is rotated.

FIG. 8shows another partial cross-sectional view of cleaning head310in operation according to some embodiments of the present technology. The partial cross-section may be vertically through third fluid channel326c.FIG. 8shows additional aspects of the seal510, which may include an inner annular sidewall512. This sidewall may be the location where electroplating residues occur, and in some embodiments this sidewall may be the only location to contact the electrolyte. When the arm on which the cleaning head is rotated, such as rotated clockwise, the cleaning head may swing down from a raised or retracted position, and may directly contact seal510along the inner annular sidewall512, such as with the contact pins previously described. The inner annular sidewall512may extend within the trench518and may recess beneath upper sidewall320of trench318of the cleaning head310. The seal may also at least partially recess across lower sidewall322in some embodiments, and lower sidewall322may be characterized by an arcuate profile to accommodate the shape of the seal to limit cleaning solution leakage between the components. By utilizing this cleaning assembly, an in situ clean may be performed on a seal to reduce or eliminate residues on the seal, which may be conductive and could affect plating operations.

The systems and components previously described may be used in a number of methods for in situ component cleaning.FIG. 9shows operations of an exemplary method900of cleaning a contact seal of an electroplating system according to some embodiments of the present technology, and which may use any of the components previously described, such as cleaning head310. Method900may include operations prior to the actual seal cleaning. For example, prior to the cleaning, a system head may be positioned, such as inverted, to expose a contact seal or other component to be cleaned. An arm of a cleaning assembly may position within an interior of the head, and may rotate a cleaning head into contact with the contact seal or other component. A cleaning solution may be delivered into contact with the seal through the cleaning head at operation910. The cleaning head may be positioned to physically contact the electroplating system contact seal, and the cleaning solution may be delivered through a first fluid channel of the cleaning head. The seal may be rotated across the cleaning head at operation920, which may allow an entire surface to be contacted by the cleaning solution. The cleaning solution may be extracted from the cleaning head during the rotation and delivery of the cleaning solution through a second fluid channel radially offset from the first fluid channel in a direction of rotation of the electroplating system at operation930. Although illustrated in a particular succession, operation910and operation920may occur in any order, including concurrently. For example, method900may begin by rotating the seal, which may operate to draw the cleaning solution as it enters the cleaning head from a delivery channel to a retrieval channel. By initiating the operation with rotation of the seal, a balance may be developed between fluid flow and evacuation rates utilizing the seal to facilitate delivery of the fluid from delivery channels to return flow channels. Additionally, the seal rotation of operation920may be performed simultaneously with delivery of the solution.

In some embodiments, the cleaning solution may be or include an acidic solution. The residues may include metal ions or materials on the surface of the seal, which may be removed by an acid wash. The acidic solution may be selected based on the metal being electroplated, and may include nitric acid, acetic acid, sulphuric acid, or any other organic or inorganic acid as well as acid mixture that may facilitate removal of copper materials, nickel materials, tin-silver solders, or other materials that may be electroplated and may cause residues to form on the seal, including metal-organic materials and complexed metals, such as, for example, silver in a tin silver bath.

As previously explained, the cleaning head may be formed of a hydrophobic material, which may limit or prevent wetting of the cleaning solution onto the cleaning head materials. The delivery of the cleaning solution, removal of the cleaning solution, and rotation of the seal may also be performed in a manner to limit contact of the solution with surfaces of the cleaning head, as well as to limit dripping or leakage of the solution from the cleaning head into contact with any other component of the system head. For example, an acid solution may cause damage to contacts if it is allowed to interact with the contacts, accordingly, by carefully controlling the delivery and removal of the solution, acidic solutions may be used in the present technology, unlike other in situ systems that may be limited to water. Utilizing the present technology, the cleaning solution may be substantially maintained within a volume defined in part by an inner surface of the contact seal, a trench formed within a front portion of the cleaning head, and one or more contact pins at least partially extending through the trench proximate leading and trailing edges of the cleaning head in a direction of rotation of the contact seal across the cleaning head.

In some embodiments a water rinse may be performed with water, such as deionized water, subsequent delivery and removal of the cleaning solution. The water may be delivered in substantially the same fashion as the cleaning solution. In some embodiments the water may be delivered at a greater volumetric flow rate than the cleaning solution. By delivering additional water relative to the removal rate, the water may be flowed further within the volume, such as to interact with contact pin328, or contact pin330, which may allow any residual cleaning solution to be effectively flushed from the cleaning head. Additionally, an amount of water may be leaked or ejected from the cleaning head, which may allow a rinse of the underlying contact on the system head. The present technology provides the ability to clean contact seals in situ, which limits down time of electroplating equipment, while also limiting conductive residue formation on exposed tool surfaces, which may affect plating uniformity on a substrate. Accordingly, improved throughput and quality may be afforded by systems and methods according to the present technology.

In the preceding description, for the purposes of explanation, numerous details have been set forth in order to provide an understanding of various embodiments of the present technology. It will be apparent to one skilled in the art, however, that certain embodiments may be practiced without some of these details, or with additional details. For example, other substrates that may benefit from the wetting techniques described may also be used with the present technology.

Where a range of values is provided, it is understood that each intervening value, to the smallest fraction of the unit of the lower limit, unless the context clearly dictates otherwise, between the upper and lower limits of that range is also specifically disclosed. Any narrower range between any stated values or unstated intervening values in a stated range and any other stated or intervening value in that stated range is encompassed. The upper and lower limits of those smaller ranges may independently be included or excluded in the range, and each range where either, neither, or both limits are included in the smaller ranges is also encompassed within the technology, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included. Where multiple values are provided in a list, any range encompassing or based on any of those values is similarly specifically disclosed.

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