Electrochemical planarization device for upward-facing wafer

Abstract

An exemplary substrate electrochemical planarization apparatus may include a chuck body defining a substrate support surface. The device may include a fixed wall extending from the chuck body. The device may include an electrolyte delivery port disposed radially inward of the fixed wall. The apparatus may include a mandrel positionable above the chuck body. The apparatus may include a terminal effector coupled with a lower end of the mandrel. The terminal actuator may be electrically conductive. The device may include an electrical contact extending from the chuck body or the fixed wall. An apparatus may include a current source. The current source may be configured to provide a current to an electrolyte within an open interior defined by the fixed wall.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of and priority to U.S. Patent Application No. 17 / 833,422, filed on June 6, 2022, entitled “FACE-UP WAFER ELECTROCHEMICAL PLANARIZATION APPARATUS,” which is incorporated herein by reference in its entirety. Technical Field

[0002] The present technology relates to semiconductor systems, processes, and equipment. More particularly, the present technology relates to planarizing films deposited on substrates. Background Art

[0003] Integrated circuits are typically formed on a substrate by sequential deposition of conductive, semiconductor, and / or insulating layers on a silicon wafer. Various manufacturing processes use planarization of layers on a substrate between processing steps. For example, for specific applications (e.g., planarization of a metal layer to form vias, plugs, and / or lines in trenches of a patterned layer), the overlying layer is planarized until the top surface of the patterned layer is exposed. In other applications (e.g., planarization of a dielectric layer for photolithography), the overlying layer is polished until a desired thickness remains above the underlying layer.

[0004] Chemical mechanical polishing (CMP) is a common planarization method. This planarization method generally requires the substrate to be mounted on a carrier head or polishing head. The exposed surface of the substrate is generally placed against a rotating polishing pad. The carrier head provides a controllable load on the substrate to push the substrate against the polishing pad. An abrasive polishing slurry is generally supplied to the surface of the polishing pad.

[0005] One problem in CMP is polishing the entire surface of a substrate uniformly. Oftentimes, the mechanical forces applied during the CMP operation can remove exposed portions of a first material at a faster rate than exposed portions of a second material, which can result in uneven polishing. As a result, the film thickness across the substrate is non-uniform, and some materials (such as metallic materials) can be removed faster than, for example, dielectric materials, resulting in dishing of the metallic material. This film non-uniformity can cause lithography problems and can result in a loss of die yield from a given substrate.

[0006] Therefore, there is a need for improved systems and methods that can be used to polish or planarize a substrate to produce a uniform film across the entire surface area of ​​the substrate. The present technology addresses these and other needs. Summary of the invention

[0007] An exemplary substrate electrochemical planarization apparatus may include a chuck body defining a substrate support surface. The apparatus may include a fixed wall extending from the chuck body. The apparatus may include an electrolyte delivery port disposed radially inward of the fixed wall. The apparatus may include a mandrel positionable above the chuck body. The apparatus may include a terminal effector coupled to a lower end of the mandrel. The terminal effector may be conductive. The apparatus may include electrical contacts extending from the chuck body or the fixed wall. The apparatus may include a current source. The current source may be configured to provide current to an electrolyte within an open interior defined by the fixed wall.

[0008] In some embodiments, the end effector may be characterized by a diameter of less than or about 150 mm. The spindle may be rotatable and may translate laterally relative to the chuck body. The surface of the end effector facing the substrate support surface may be flat. The fixed wall may be annular. The diameter of the end effector may be less than the inner diameter of the fixed wall. The device may include an electrolyte drain port positioned in one or both of the chuck body and the fixed wall. The device may include an edge ring disposed on the chuck body.

[0009] Some embodiments of the present technology encompass an apparatus for electrochemical planarization of a substrate. The apparatus may include a chuck body defining a substrate support surface. The apparatus may include a spindle positionable above the chuck body. The apparatus may include a rotational drive mechanism coupled to the spindle. The apparatus may include a terminal actuator coupled to a lower end of the spindle. The apparatus may include electrical contacts extending from the chuck body. The apparatus may include a current source. The current source may be configured to provide current to an electrolyte within an open interior defined by a fixed wall extending from the chuck body.

[0010] In some embodiments, the terminal effector comprises a conductive material. The apparatus may include an edge ring disposed on the chuck body. The inner diameter of the edge ring may be less than about 5% greater than the diameter of the substrate support surface. The apparatus may include a fixed wall disposed radially outward of the chuck body. The fixed wall may be annular. The diameter of the terminal effector may be less than the inner diameter of the fixed wall. The apparatus may include an electrolyte source. The apparatus may include an electrolyte delivery port fluidly coupled to the electrolyte source. The electrolyte delivery port is disposed radially inward of the fixed wall. The substrate electrochemical planarization apparatus may be disposed in a polishing chamber, the polishing chamber comprising a face-down polishing station.

[0011] Some embodiments of the present technology encompass methods of planarizing a substrate. The method may include positioning the substrate face-up atop a substrate support surface of a chuck body within an open interior defined by fixed walls extending from the chuck body. The method may include clamping the substrate to the chuck body. The method may include delivering an electrolyte to a top surface of the substrate. The method may include engaging the top surface of the substrate with a terminal effector coupled to a lower end of a mandrel. The method may include applying an electric current to the electrolyte.

[0012] In some embodiments, the method may include translating the mandrel laterally while rotating the terminal effector against the top surface of the substrate. The method may include moving the terminal effector relative to the substrate. While rotating the terminal effector against the top surface of the substrate, a downward force of less than or about 2.0 psi is applied to the terminal effector. While rotating the terminal effector against the top surface of the substrate, a central axis of the terminal effector is offset from a central axis of the substrate. The method may include draining electrolyte from the open interior via an electrolyte drain port positioned in one or both of the chuck body and the fixed wall.

[0013] The present technology can provide many benefits over conventional systems and techniques. For example, the electrochemical planarization apparatus described herein can make it possible to planarize a substrate during a planarization operation without removing some portions of the exposed material at a faster rate than other portions of the exposed material. Often, the planarization techniques described herein can be used before and / or after conventional CMP operations. This can enable the uniformity of film thickness and metal features across the substrate surface to be improved, which can result in increased die yield. These and other embodiments, along with their advantages and features, are described in more detail in conjunction with the following description and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] A further understanding of the nature and advantages of the disclosed technology may be realized by reference to the remaining portions of the specification and the accompanying drawings.

[0015] Figure 1 A schematic cross-sectional view of an exemplary chemical mechanical planarization system is shown in accordance with some embodiments of the present technology.

[0016] Figure 2 A schematic partial cross-sectional view of an exemplary electrochemical planarization device according to some embodiments of the present technology is shown.

[0017] Figure 3 A schematic partial top view of an exemplary polishing chamber according to some embodiments of the present technology is shown.

[0018] Figure 4 is a flow chart of an exemplary method of planarizing a substrate according to some embodiments of the present technology.

[0019] Some of the drawings in the drawings are included as schematic diagrams. It will be understood that the drawings are for illustrative purposes and are not to be considered to scale unless explicitly stated to be to scale. Furthermore, as schematic diagrams, the drawings are provided to aid understanding and may not include all aspects or information compared to realistic representations and may include exaggerated material for illustrative purposes.

[0020] In the accompanying drawings, similar components and / or features may have the same reference number. In addition, various components of the same type may be distinguished by a letter following the reference number that distinguishes between similar components. If only the first reference number is used in the specification, the description may apply to any of the similar components having the same first reference number, regardless of the letter. DETAILED DESCRIPTION

[0021] In conventional chemical mechanical polishing (CMP) operations, it is often difficult to uniformly polish the surface of a substrate. Conventional CMP polishing includes a substrate positioned face-down on a polishing pad, with a carrier that holds the substrate against a rotating polishing pad. However, the pressure between the polishing pad and the substrate typically applies mechanical forces that cause non-uniform film thickness post-polishing operations. For example, this mechanical force can cause dishing of metallic material in the grooves that is exposed on the surface of the substrate. These problems can lead to non-uniformity issues that result in lower die yields. Additionally, wear of the metallic material in the grooves can result in electrical connections on the final integrated circuit or other device that are damaged and / or too thin, which can result in increased heat and subsequent failure of the connection when current is passed through the electrical connection.

[0022] The present technology overcomes the problems of conventional CMP systems by providing an electrochemical planarization device that can be used to planarize metal features (e.g., copper, cobalt, molybdenum, tungsten, and / or ruthenium features) on a substrate while minimizing non-uniformity and avoiding depression or other erosion of metal material in grooves or other recesses formed between regions of the film. Specifically, an electrochemical treatment can be provided so that only metal material that is in contact with the surface of the conductive terminal effector is selectively removed, and any material below the surface of the non-metallic film (e.g., in the grooves or other recesses) can be avoided from being removed because such material will not contact the surface of the terminal effector. These techniques can be used in conjunction with conventional CMP systems (which can planarize non-metallic features) to produce substrates with improved thickness uniformity. Additionally, embodiments can include a clamping mechanism that can help flatten the substrate during planarization, which can further improve the uniformity achieved during the planarization operation. Embodiments can enable the terminal effector to be translated laterally relative to the substrate, which can enable the electrochemical planarization device to improve non-uniformity issues.

[0023] Although the remainder of the disclosure will routinely identify specific film measurement processes utilizing the disclosed techniques, it will be readily appreciated that these systems and methods may be equally applied to a variety of other semiconductor processing operations and systems. Therefore, the present technology should not be considered limited to use with only the described electrochemical planarization systems or processes. Prior to describing systems and methods or operations for exemplary process sequences according to some embodiments of the present technology, the present disclosure will discuss one possible system that may be used with the present technology. It will be understood that the technology is not limited to the described equipment, and that the processes discussed may be performed in any number of processing chambers and systems, along with any number of modifications, some of which will be specified later.

[0024] Figure 1 A schematic cross-sectional view of an exemplary polishing system 100 according to some embodiments of the present technology is shown. The polishing system 100 includes a platform assembly 102, which includes a lower platform 104 and an upper platform 106. The lower platform 104 can define an internal volume or cavity through which a connection can be made, and in which an endpoint detection device or other sensor or device, such as an eddy current sensor, an optical sensor, or other components for monitoring a polishing operation or a component, can be included. For example, and as further described below, a fluid coupling can be formed with a wire extending through the lower platform 104, and the fluid coupling can enter and exit the upper platform 106 through the back side of the upper platform. The platform assembly 102 can include a polishing pad 110 mounted on a first surface of the upper platform. A substrate carrier 108 or a carrier head can be disposed above the polishing pad 110 and can face the polishing pad 110. The platform assembly 102 can rotate about an axis A, and the substrate carrier 108 can rotate about an axis B. The substrate carrier can also be configured to sweep back and forth along the platform assembly from the inner radius to the outer radius, which can partially reduce uneven wear of the surface of the polishing pad 110. The polishing system 100 can also include a fluid delivery arm 118 positioned above the polishing pad 110, and the fluid delivery arm 118 can be used to deliver a polishing fluid (such as a polishing slurry) onto the polishing pad 110. Additionally, a pad conditioning assembly 120 can be disposed above the polishing pad 110 and can face the polishing pad 110.

[0025] In some embodiments performing a chemical mechanical polishing process, a rotating and / or sweeping substrate carrier 108 may apply a downward force against a substrate 112, which is shown in phantom and may be disposed within or coupled to the substrate carrier. As the polishing pad 110 rotates about the central axis of the platen assembly, the applied downward force may press the material surface of the substrate 112 against the polishing pad 110. The interaction of the substrate 112 against the polishing pad 110 may occur in the presence of one or more polishing fluids delivered by a fluid delivery arm 118. A typical polishing fluid may include a slurry formed from an aqueous solution in which abrasive particles may be suspended. Typically, the polishing fluid contains a pH adjuster and other chemically active components, such as an oxidizing agent, which may enable chemical mechanical polishing of the material surface of the substrate 112.

[0026] The pad conditioning assembly 120 can be operated to apply a fixed abrasive conditioning disk 122 against the surface of the polishing pad 110, which can be rotated as previously described. The conditioning disk can be operated against the pad before, after, or during polishing of the substrate 112. Conditioning the polishing pad 110 with the conditioning disk 112 can maintain the polishing pad 110 in a desired condition by abrading, rejuvenating, and removing polishing byproducts and other debris from the polishing surface of the polishing pad 110. The upper platform 106 can be disposed on a mounting surface of the lower platform 104 and can be coupled to the lower platform 104 using a plurality of fasteners 138, such as an annular flange-shaped portion extending through the lower platform 104.

[0027] The polishing platform assembly 102, and thus the upper platform 106, can be appropriately sized for any desired polishing system, and can be sized for any diameter of substrate, including 200 mm, 300 mm, 450 mm, or larger. For example, a polishing platform assembly configured to polish a 300 mm diameter substrate can be characterized by a diameter greater than about 300 mm, such as between about 500 mm and about 1000 mm, or greater than about 500 mm. The platform can be adjusted in diameter to accommodate substrates characterized by larger or smaller diameters, or for a polishing platform 106 that is sized for polishing multiple substrates simultaneously. The upper platform 106 can be characterized by a thickness between about 20 mm and about 150 mm, and can be characterized by a thickness less than or about 100 mm, such as less than or about 80 mm, less than or about 60 mm, less than or about 40 mm, or less. In some embodiments, the ratio of the diameter to the thickness of the polishing platform 106 can be greater than or about 3:1, greater than or about 5:1, greater than or about 10:1, greater than or about 15:1, greater than or about 20:1, greater than or about 25:1, greater than or about 30:1, greater than or about 40:1, greater than or about 50:1, or greater.

[0028] The upper and / or lower platforms may be formed of a suitably strong, lightweight, and polishing fluid resistant material, such as aluminum, an aluminum alloy, or stainless steel, although any number of materials may be used. The polishing pad 110 may be formed of any number of materials, including polymeric materials, such as polyurethane, polycarbonate, fluoropolymers, polytetrafluoroethylene, polyphenylenesulfide, or any combination of these or other materials. Additional materials may be or include open or closed cell foamed polymers, elastomers, felt, impregnated felt, plastic, or any other material that may be compatible with the process chemistry. It will be understood that the polishing system 100 is included to provide suitable references to the components discussed below that may be incorporated into the system 100, however the description of the polishing system 100 is not intended to limit the present technology in any way, as embodiments of the present technology may be incorporated into any number of polishing systems that may benefit from the components and / or functionality further described below.

[0029] Figure 2 A schematic cross-sectional view of an exemplary electrochemical planarization apparatus 200 according to some embodiments of the present technology is illustrated. The apparatus 200 may be used to perform a planarization operation. The apparatus 200 may show a partial view of the components discussed and may be incorporated into a semiconductor processing system. The apparatus 200 may include a substrate support 205. The substrate support 205 may receive and support a substrate 210 during one or more processing operations. In some embodiments, the substrate support 205 may include a chuck body 215, which may define a substrate support surface 217. The chuck body 215 may include associated channels or components to operate as a vacuum chuck, an electrostatic chuck, and / or any other type of clamping system. For example, the chuck body 215 may define a number of channels 220 coupled to a vacuum source 225. The vacuum source 225 may create a negative pressure within the channel 220, which clamps the substrate 210 to the chuck body.

[0030] In other embodiments, the chuck body 215 may include an electrostatic chuck. In such embodiments, the chuck body 215 may include associated channels or components to operate as an electrostatic chuck. For example, the electrostatic chuck body 215 may be formed of an electrically conductive material (such as metalloid aluminum or any other material that may be thermally and / or electrically conductive) and may be coupled to an electrical power source (such as a DC power supply, a pulsed DC power supply, an RF bias power supply, a pulsed RF power supply or a bias power supply, or a combination of these or other power supplies) through a filter, which may be an impedance matching circuit to enable the electrostatic chuck body 215 to operate as an electrode. In other embodiments, the top portion of the electrostatic chuck body 215 may be formed of a dielectric material. In such embodiments, the electrostatic chuck body 215 may include separate electrodes that may be embedded within the chuck body 215 adjacent to the substrate support surface. Each electrode may be electrically coupled to a DC power supply that provides energy or voltage to the electrode. In operation, the substrate 210 may at least partially contact the substrate support surface of the chuck body, which may create a contact gap, and this may substantially create a capacitive effect between the surface of the pedestal and the substrate. A voltage may be applied to the contact gap, which may generate an electrostatic force for clamping.

[0031] A plurality of lift rods 227 may extend through a plurality of holes formed in the chuck body 215. When the lift rods 227 are in a normal position (i.e., retracted relative to the chuck body 215), the lift rods 227 have a first end that is substantially flush with or slightly recessed from the top surface of the chuck body 215. The first end may be flared or enlarged (not shown) to prevent the lift rods 227 from falling through the holes formed in the chuck body 215. In addition, the lift rods 227 have a second end that extends beyond the underside of the chuck body 215.

[0032] The edge ring 230 can be disposed atop the chuck body 215. For example, the edge ring 230 can be positioned around the substrate support surface 217 such that the substrate 210 is disposed within the open interior of the edge ring 230. The edge ring 230 can help maintain the substrate 210 in a desired position as the end effector 245 moves relative to the top surface of the substrate 210. The inner diameter of the edge ring 230 can be less than or about 5% greater than the diameter of the substrate 210, less than or about 4% greater than the diameter of the substrate 210, less than or about 3% greater than the diameter of the substrate 210, less than or about 2% greater than the diameter of the substrate 210, less than or about 1% greater than the diameter of the substrate 210, less than or about 0.5% greater than the diameter of the substrate 210, or less. For example, for a substrate 210 having a diameter of 300 mm, the edge ring 230 can have an inner diameter in a range of at least 300 mm to about 315 mm, although the inner diameter can be generally between or about 300.5 mm and 305 mm. The thickness of the edge ring 230 can substantially match the thickness of the substrate 210. For example, the thickness of the edge ring 230 can be within or about 3% of the thickness of the substrate 210, within or about 2% of the thickness of the substrate 210, within or about 1% of the thickness of the substrate 210, within or about 0.5% of the thickness of the substrate 210, or less. For example, for a substrate 210 having a thickness of 1 mm, the thickness of the edge ring 230 may be between or about 0.970 mm and 1.030 mm, between or about 0.980 mm and 1.020 mm, between or about 0.990 mm and 1.010 mm, between or about 0.995 mm and 1.005 mm, or about 1 mm. In some embodiments, the top surface of the chuck body 215 on which the edge ring 230 is disposed may be raised or lowered. In such embodiments, the thickness of the edge ring 230 can be adjusted so that the top surface of the edge ring 230 is within or approximately 3% of the height of the top surface of the substrate 210, within or approximately 2% of the height of the top surface, within or approximately 1% of the height of the top surface, within or approximately 0.5% of the height of the top surface, or less.

[0033] The edge ring 230 may be removably coupled to the chuck body 215. For example, one or more clamps, fasteners, and / or other coupling mechanisms may be used to secure the edge ring 230 to the top surface of the chuck body 215. This may enable the edge ring 230 to be removed for repair, cleaning, and / or replacement.

[0034] The device 200 may include a spindle 235 that may be positioned above the chuck body 215. Although shown here as having a hollow cylindrical body, the spindle 235 may be formed in other shapes and / or may be solid in various embodiments. The spindle 235 may be rotatable and vertically and / or laterally translatable relative to the chuck body 215. For example, the spindle 235 may be coupled to an arm 240. Although shown here as having a hollow cylindrical body, the arm 240 may be formed in other shapes and / or may be solid in various embodiments. The arm 240 may be vertically and / or laterally translatable relative to the chuck body 215. The spindle 235 and / or the arm 240 may be coupled to one or more motors and / or other drive mechanisms that may drive the rotation and / or translation of the spindle 235. The bottom end of the spindle 235 may include an end effector 245. The end effector 245 can be removably coupled to the bottom end of the mandrel 235, which can allow the end effector 245 to be refurbished, cleaned, and / or replaced as needed. For example, the end effector 245 can be coupled to the bottom end of the mandrel 235 using an adhesive (such as a pressure sensitive adhesive), a snap connector, a hook and loop connector, and / or other coupling mechanisms that can enable the end effector 245 to be removably coupled to the mandrel 235. The current source 275 can apply current to the electrical contacts 270, the chuck body 215, and / or the fixed wall 260 to the mandrel 235, the arm 240, and / or the end effector 245. An electrical circuit can be completed between the electrical contacts 270, the electrolyte, the metal material on the substrate 210, and the end effector 245 delivering the current to the metal material to perform electrochemical planarization of the substrate 210.

[0035] The terminal effector 245 may include a substantially planar exposed (e.g., lower) contact surface that may be formed of and / or otherwise include a conductive material. For example, the exposed contact surface may be at least or about 95% flat, at least or about 97% flat, at least or about 99% flat, or greater. Such a design may ensure that the exposed surface may maintain uniform contact with the surface of the substrate 210 during planarization to ensure that the metal material is planarized with a high degree of accuracy. The terminal effector 245 may be a mesh material, such as a conductive mesh (such as a metal), which is covered in a polymeric material. In some embodiments, the terminal effector 245 may include and / or be formed of a conductive polymeric material. The conductive material may be electrically coupled to the current source 275 via one or more wires or other conductors that may extend through, be coupled to, and / or form part of the mandrel 235. The use of a polymeric material may reduce or eliminate scratching of the substrate film that may otherwise occur if a material such as a metal is used.

[0036] The end effector 245 may have a circular, polygonal, annular, or any other shape, and may be sized so that the end effector 245 can planarize only certain areas of the substrate 210. For example, the diameter of the end effector 245 may be smaller than the diameter of the substrate 210 (and smaller than the inner diameter of the edge ring 230). For example, the diameter of the end effector 245 may be less than or approximately 90% of the diameter of the substrate 210, less than or approximately 80% of the diameter of the substrate 210, less than or approximately 70% of the diameter of the substrate 210, less than or approximately 60% of the diameter of the substrate 210, less than or approximately 50% of the diameter of the substrate 210, less than or approximately 40% of the diameter of the substrate 210, less than or approximately 30% of the diameter of the substrate 210, less than or approximately 20% of the diameter of the substrate 210, less than or approximately 15% of the diameter of the substrate 210, less than or approximately 10% of the diameter of the substrate 210, less than or approximately 8% of the diameter of the substrate 210, less than or approximately 6% of the diameter of the substrate 210, less than or approximately 4% of the diameter of the substrate 210, less than or approximately 2% of the diameter of the substrate 210, or less. For example, for a 300 mm substrate 210, the diameter of the end effector 245 may be less than or about 270 mm, less than or about 240 mm, less than or about 210 mm, less than or about 180 mm, less than or about 150 mm, less than or about 120 mm, less than or about 90 mm, less than or about 60 mm, less than or about 45 mm, less than or about 30 mm, less than or about 24 mm, less than or about 18 mm, less than or about 12 mm, less than or about 6 mm, or less. However, it is also contemplated that the diameter of the end effector 245 may be greater than or about 100% of the diameter of the substrate 210. For example, for a 300 mm substrate 210, the outer diameter of the end effector 245 may be greater than or about 300 mm.

[0037] In an embodiment, the device 200 may include a plurality of end effectors 245. For example, the device 200 may include at least or about 1 end effector, at least or about 2 end effectors, at least or about 3 end effectors, at least or about 4 end effectors, or more. Each of the plurality of end effectors 245 may be coupled to the bottom end of the mandrel 235, and the mandrel 235 may be coupled to the arm 240, as previously described. With the plurality of end effectors 245, processing time may be reduced, which may increase overall processing throughput. With the plurality of end effectors 245, current density may be increased at specific locations, which may allow for more efficient removal of metallic material.

[0038] The device 200 may include an electrolyte delivery port 250. The electrolyte delivery port 250 may be coupled to an electrolyte source 255 and may deliver electrolyte from the electrolyte source 255 to the surface of the substrate 210 during a planarization operation. The electrolyte may include an aqueous solution containing ions that is conductive through the movement of the ions. For example, the electrolyte can be or include sulfuric acid, citric acid, ethylenediamine, hexamethylenediamine, amino acid, ammonium oxalate, ammonium citrate, ammonium succinate, monobasic potassium citrate, dibasic potassium citrate, tribasic potassium citrate, tartaric acid, potassium tartrate, ammonium tartrate, succinic acid, potassium succinate, oxalic acid, potassium oxalate, malic acid, salicylic acid, benzotriazole, mercaptobenzotriazole, 5-methyl-1-benzotriazole, hydroxybenzotriazol, potassium hydroxide, ammonium hydroxide, and combinations thereof, or any other suitable electrolytic material. The electrolyte can include between about 1 weight percent and about 0.01 weight percent of silicon oxide, aluminum oxide, or zirconium oxide abrasive particles. Silicon oxide, aluminum oxide, or zirconium oxide abrasive particles may be characterized by a D50 of about 50 nm. In embodiments, the electrolyte may include various additives, such as chelating agents, lubricants, oxidants, corrosion inhibitors, pH adjusters, and / or catalysts. Chelating agents may help to bond the removed metal material to avoid its redeposition. Lubricants may avoid scratches of metal materials that are not removed from the substrate 210. In order to help keep the electrolyte from propagating away from the substrate 210, the device 200 may include a fixed wall 260. The fixed wall 260 may be an annular body extending from the chuck body 215. The fixed wall 260 may be positioned radially inward of both the edge ring 230 and the electrolyte delivery port 250 so that any electrolyte delivered to the substrate 210 via the electrolyte delivery port 250 is kept adjacent to the substrate 210. Although shown as the electrolyte delivery port 250 being positioned above the fixed wall 260, in some embodiments, the electrolyte delivery port 250 may extend through a portion of the fixed wall 260 and / or the chuck body 215. To help minimize the amount of electrolyte required for a given planarization operation, the inner surface of the fixed wall 260 can be positioned adjacent to and can contact the outer surface of the edge ring 230 (although in some embodiments there can be a gap between the edge ring 230 and the fixed wall 260). The fixed wall 260 can be integrally formed with the chuck body 215 and / or can be a separate component that is subsequently coupled to the chuck body 215.The fixed wall 260 may be coupled to the outer surface of the chuck body 215 as illustrated herein and / or may be disposed atop the chuck body 215 (similar to the edge ring 230) in other embodiments. That is, the fixed wall 260 may extend from the chuck body 215. The device 200 may include an electrolyte drain 265 that may be used to passively drain and / or actively pump electrolyte out of an area within the fixed wall 260 before, during, and / or after a given planarization operation. For example, the electrolyte drain 265 may extend through the fixed wall 260 and / or the chuck body 215. In some embodiments, the electrolyte drain 265 may also extend through the edge ring 230. In such embodiments, the edge ring 230 may include one or more alignment features (such as rods) that ensure that the edge ring 230 is properly oriented on the chuck body 215 to align portions of the electrolyte drain 265 on the edge ring 230 with portions of the electrolyte drain 265 on the chuck body 215 and / or the fixed wall 260. Although shown with only a single electrolyte drain port 265, it will be appreciated that multiple electrolyte drain ports may be used in various embodiments. For example, one or more electrolyte drain ports 265 may be positioned radially outward of the substrate support surface 217 (such as outward of the edge ring 230, through the edge ring 230, and / or below the edge ring 230) and / or one or more electrolyte drain ports 265 may extend through the substrate support surface 217. Such a configuration may better enable electrolyte to be removed from all areas of the chuck body 215. Where multiple electrolyte drain ports 265 are positioned within a given area of ​​the chuck body 215, the electrolyte drain ports may be positioned at regular and / or irregular intervals around the chuck body 215.

[0039] In an embodiment, an electrolyte may be delivered to the substrate 210. The electrolyte may contain ions that are conductive by the movement of the ions. When an electric current is applied, the cations of the electrolyte are pulled to the electrode with abundant electrons, and the anions of the electrolyte are pulled to the electrode lacking electrons. The movement of the anions and cations in the solution in opposite directions is integrated into the current. The electrolyte may be free of any abrasive particles, which may provide coarse particles that cause the terminal effector 245 to mechanically remove the film on the substrate. The electrolyte may be continuously and / or periodically delivered to the substrate 210 via the electrolyte delivery port 250, and may be removed via the electrolyte discharge port 265. In operation, a suitable amount of contact with the upper surface of the substrate 210 may be provided to the device 200. For example, an electrolyte greater than or about 500 cubic centimeters (cc) may be provided. In some embodiments, smaller amounts of electrolyte may be provided, such as less than or about 500cc, less than or about 450cc, less than or about 400cc, less than or about 350cc, less than or about 300cc, less than or about 250cc, less than or about 200cc, less than or about 150cc, less than or about 100cc, less than or about 50cc, or less.

[0040] The device 200 may include an electrical contact 270. The electrical contact 270 may extend from the chuck body 215 and / or the fixed wall 260. In operation, the electrical contact 270 may provide current to the electrolyte within the open interior defined by the fixed wall 260. When the conductive terminal effector 245 contacts the metal features of the substrate 210, the current 275 applied to the electrolyte may facilitate the removal of material during the planarization operation. The current 275 may be applied from the electrical contact 270, the chuck body 215, and / or the fixed wall 260 to the mandrel 235, the arm 240, and / or the terminal effector 245. The current 275 may complete the circuit necessary to perform electrochemical planarization of the substrate 210. Although only a single electrical contact 270 is shown, it will be understood that multiple electrical contacts may be used in various embodiments. For example, one or more electrical contacts 270 may be positioned around the fixed wall 260. This configuration may better enable current to be applied to the electrolyte. Where a plurality of electrical contacts 270 are positioned about the stationary wall 260 , the electrical contacts 270 may be positioned at regular and / or irregular intervals about the stationary wall 260 .

[0041] To monitor the removal of material, the device may include an optical sensor 280. The optical sensor 280 may be, for example, a camera, a depth sensor, an optical interferometer, an eddy current sensor, an image sensor capable of machine learning (e.g., to detect metal material residues), or any other device for monitoring the removal of material. The optical interferometer may detect the surface topography of the metal material. The eddy current sensor may monitor the thickness of the overloaded metal material (e.g., metal material extending above and / or extending beyond the feature). The optical sensor 280 may be positioned above the substrate 210. In operation, the field of view 285 may extend from the optical sensor 280 toward the substrate 210. The optical sensor may monitor the removal of the desired material. Additional equipment (such as a processor and / or controller) may relay information about the removal of material from the substrate 210. The additional equipment may indicate the area to which the mandrel 235 moves and contacts the substrate 210 where material is to be removed. For example, where one or more sensors determine that copper (or other metallic material) outside of a trench is to be removed, the optical sensor 280 may direct the end effector 245 to a detected position until no metallic material remains above the trench or feature in the substrate 210. In some embodiments, the relative height or other amount of metal for removal may be detected. Based on this measurement, the amount of time for the end effector 245 may be set to ensure that all excess metallic material is removed. Although only a single optical sensor 280 is shown, it will be understood that multiple optical sensors may be used in various embodiments. For example, one or more optical sensors 280 may be positioned at different locations above the substrate 210. This configuration may better enable removal of material from the substrate 210 because different viewing angles / sensing angles may be provided that help avoid problems when the mandrel 235 and / or the end effector 245 are disposed between a given optical sensor 280 and the substrate 210. Where multiple optical sensors 280 are positioned above the substrate 210, the optical sensors 280 may be positioned at regular and / or irregular intervals above the substrate 210.

[0042] In operation, the substrate 210 may be positioned face-up within the open interior of the edge ring 230 atop the substrate support surface 217. By positioning the substrate 210 face-up atop the substrate support surface 217, hydrogen bubbles trapped on the surface of the substrate 210 may be reduced or eliminated with the electrolyte atop the substrate 210. Additionally, doming and / or bowing of the substrate 210 during operation may be reduced. The face-up configuration may also reduce or avoid accumulation of residues, such as residues of removed metallic materials, on the surface of the substrate 210 during operation. A clamping force, such as a vacuum force and / or an electrostatic clamping force, may be applied to the substrate 210 to clamp the substrate 210 to the substrate support surface 217. In some examples, in addition to clamping the substrate 210 to the substrate support surface 217, the clamping force may also reduce and / or eliminate any bowing of the substrate 210 such that the substrate 210 is substantially flat prior to initiation of any planarization operation. The mandrel 235 and the end effector 245 can be positioned above the substrate 210. The end effector 245 can be positioned against the surface of the substrate 210 and can be rotated to planarize the film on the substrate 210. Typically, the mandrel 235 and the end effector 245 can be rotated at a rate of between or about 60 rpm and 200 rpm, between or about 80 rpm and 180 rpm, between or about 100 rpm and 160 rpm, or between or about 120 rpm and 140 rpm, although other rates are possible in various embodiments. The downward force of the end effector 245 can be adjusted by a drive mechanism based on the requirements of a particular planarization operation. To avoid sag or non-uniform removal of material, the downward force can be negligible. For example, this force may be adjusted between about 0.1 psi and about 2.0 psi, and may be less than or about 1.5 psi, less than or about 1.0 psi, less than or about 0.8 psi, less than or about 0.6 psi, less than or about 0.4 psi, less than or about 0.2 psi, or less, although other degrees of force may be utilized in various embodiments. The end effector 245 may be coaxially aligned with the substrate 210, which may be used to produce symmetrical planarization of the substrate 210. In other embodiments, the end effector 245 may be offset from the central axis of the substrate 210, which may enable asymmetrical planarization to be performed. In some embodiments, the end effector 245 (and the mandrel 235) may be laterally translated (or swept) during rotation of the end effector 245 to control the eccentricity of the end effector 245 to change the planarization pattern of the device 200.Typically, the lateral distance covered during the sweep can be less than or about 10 mm, 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, or less. The rate of the sweeping movement can be adjusted based on the initial and / or desired film thickness profile.

[0043] Such operation of the apparatus 200 can achieve uniform or near uniform removal of exposed material on the surface of the substrate 210. Additionally, by using a laterally translatable mandrel 235, the apparatus 200 can be swept and / or otherwise translated to address asymmetric non-uniformity issues. The planarization described herein can be used in conjunction with conventional CMP polishing operations to uniformly polish the entire film surface of the substrate. For example, planarization can be performed before and / or after conventional face-down CMP polishing.

[0044] Although primarily discussed with respect to improving film uniformity across a substrate, it will be appreciated that the techniques described herein may also be used in some embodiments to produce other film thickness profiles by providing the ability to tailor the planarization operation without affecting planarization of the remainder of the substrate.

[0045] Figure 3 A schematic top view of a polishing chamber 300 according to some embodiments of the present technology is depicted. The chamber 300 may include any number of stations 305 that can be used to perform one or more polishing operations. For example, the chamber 300 may include at least or about 1 station, at least or about 2 stations, at least or about 3 stations, at least or about 4 stations, or more. Each station 305 may include one or more polishing systems. For example, the station 305 may include one or more conventional CMP systems 305a (such as system 100) and / or one or more electrochemical planarization devices 305b (such as device 200), face-up edge planarization devices, and other trimming stations 305c. The various stations may be provided in any number, arrangement, and / or combination. As just one example, the chamber 300 may include two CMP stations 305a, one electrochemical planarization device 305b, and one trimming station 305c. The chamber 300 may include one or more robots 310 that can be used to move a substrate from one station 305 to another. For example, the robot 310 may transfer a substrate between one of the CMP stations 305a and the electrochemical planarization device 305b.

[0046] Figure 4Exemplary operations in a method 400 for planarizing a substrate according to some embodiments of the present technology are shown. Method 400 can be performed using an electrochemical planarization device, such as the electrochemical planarization device 200 described herein. In some embodiments, method 400 may include operations before the substrate is planarized. For example, before planarization, the substrate may have one or more deposition and / or etching operations that have been performed, as well as any planarization or other processing operations that have been performed. Method 400 may include a certain number of operations that can be automatically performed within the system to limit manual interaction and provide increased efficiency and accuracy compared to manual operations. Method 400 can be performed in conjunction with a conventional CMP polishing process. For example, a conventional CMP polishing process can be performed before and / or after method 400.

[0047] Method 400 may include, at operation 405, positioning a substrate face-up within a top of a substrate support surface of a chuck body within an open interior, the open interior being defined by a fixed wall extending from the chuck body. At operation 410, the substrate may be clamped to the chuck body. For example, a clamping mechanism may be activated to provide a vacuum clamping force and / or an electrostatic clamping force, which may clamp the substrate against the substrate support surface and / or flatten the substrate. At operation 415, an electrolyte may be provided to the open interior defined by the chuck body and the fixed wall. In an embodiment, the electrolyte may be provided to the top surface of the substrate, and in some embodiments, may cover the entire top surface. The electrolyte may be any solution or medium containing conductive ions. The electrolyte may facilitate an electrochemical operation to remove material. At operation 420, the top surface of the substrate may be engaged with a ring-shaped terminal effector. Such contact may form a closed circuit, which allows electrochemical removal of material during a flattening operation. At operation 425, an electric current may be applied to the electrolyte. This electric current in conjunction with a suitable electrolyte may drive an electrochemical reaction on the surface of the substrate exposed to the electrolyte. In operation, when an electric current is applied to the electrolyte, the conductive film can be removed from the surface of the substrate. In addition, in operation, the current can be changed. Depending on the position of the end effector relative to the position on the substrate, this current can be increased or decreased, as well as maintained. For example, depending on the deposition method, the thickness of the metal profile can be asymmetric, and a portion of the substrate can have a thicker metal profile. Accordingly, the current can be changed to compensate for the thickness of the metal profile in various areas on the substrate.

[0048] At operation 430, the end effector may be rotated against the top surface of the substrate to flatten the substrate. For example, the central axis of the end effector may be coaxial with the central axis of the substrate, while rotating the end effector against the top surface of the substrate to uniformly flatten the substrate. The central axis of the end effector may be offset from the central axis of the substrate, while rotating the end effector against the top surface of the substrate to flatten and eliminate the asymmetric film thickness non-uniformity problem. In some embodiments, the end effector may be translated or swept laterally around the surface of the substrate, while rotating the end effector against the top surface of the substrate to flatten the substrate into a desired pattern and / or to achieve a desired film thickness profile. In operation, the end effector may be swept across the substrate. Depending on the material to be removed and the thickness of the material, the dwell time of the end effector at some locations is shorter or longer than the dwell time of the end effector at other locations. The sweeping movement of the end effector across the substrate can radially control the removal profile of the metal material. In an embodiment, the chuck body may also be rotated. By a combination of end effector sweeping and chuck body rotation, the metal material removal profile can be adjusted radially and angularly. A negligible (such as less than or about 2.0 psi) or zero downward force can be applied to the end effector while rotating the end effector against the top surface of the substrate. The amount of downward force (which can be negligible to ensure more electrochemical removal rather than mechanical removal) can be adjusted to control the rate of planarization of the electrochemical planarization device. Planarization with the application of current in the presence of an electrolyte can be used as the opposite of electroplating (i.e., removal of material versus application of material).

[0049] The electrolyte may be continuously and / or periodically delivered to the substrate via the electrolyte delivery port.Once a given planarization operation has been completed, the electrolyte may be removed from the device, such as by draining and / or pumping the electrolyte via the electrolyte drain port.

[0050] In the foregoing description, for the purpose of explanation, many details have been set forth to provide an understanding of various embodiments of the present technology. However, it will be apparent to one skilled in the art that certain embodiments may be practiced without some of these details or with additional details.

[0051] Several embodiments have been disclosed, and those skilled in the art will recognize that various modifications, alternative configurations, and equivalents may be used without departing from the spirit of the embodiments. Additionally, a number of well-known processes and elements have not been described to avoid unnecessary confusion of the present technology. Therefore, the above description should not be taken as limiting the scope of the present technology.

[0052] In the case of providing a range of values, unless the context clearly indicates otherwise, it will be understood that each intermediate value of the smallest part of the unit to the lower limit between the upper and lower limits of the range is also explicitly disclosed. Any narrower range between any recorded value or unrecorded intermediate value and any other recorded or intermediate value in the recorded range is also covered. The upper and lower limits of those smaller ranges can be independently included in this range or excluded from this range, and are affected by any clearly excluded limits in the recorded range, and each range in which any limit in the smaller range is included, no limit is included, or both limits are included is also covered in the present technology. In the case where the recorded range includes one or both of the limits, the scope of excluding any one or both of these included limits is also included.

[0053] 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 heater" includes a plurality of such heaters and reference to "the projection" includes reference to one or more projections and equivalents thereof known to those skilled in the art, and so forth.

[0054] Furthermore, when used in this specification and in the claims that follow, the words “comprise(s),” “comprising,” “contain(s),” “containing,” “include(s),” and “including” are intended to specify the presence of recited features, integers, components, or operations, but they do not preclude the presence or addition of one or more other features, integers, components, operations, actions, or groups.

Claims

1. A substrate electrochemical planarization device, comprising: a chuck body defining a substrate supporting surface; a fixed wall extending from the chuck body; an electrolyte delivery port, disposed radially inward of the fixed wall; a mandrel positionable above the chuck body; a terminal effector coupled to a lower end of the mandrel, wherein the terminal effector is electrically conductive; an electrical contact extending from the chuck body or the fixed wall; as well as A current source is provided, wherein the current source is configured to provide current to an electrolyte within the open interior defined by the fixed wall.

2. The substrate electrochemical planarization device according to claim 1, wherein: The end effector is characterized by a diameter of less than or about 150 mm.

3. The substrate electrochemical planarization device according to claim 1, wherein: The spindle is rotatable and can translate laterally relative to the chuck body.

4. The substrate electrochemical planarization device according to claim 1, wherein: The surface of the end effector facing the substrate supporting surface is flat.

5. The substrate electrochemical planarization device according to claim 1, wherein: The fixed wall is annular; and The diameter of the end effector is smaller than the inner diameter of the fixed wall.

6. The substrate electrochemical planarization device according to claim 1, further comprising: An electrolyte drain port is positioned in one or both of the chuck body and the fixed wall.

7. The substrate electrochemical planarization device according to claim 1, further comprising: An edge ring is disposed on the chuck body.

8. A substrate electrochemical planarization device, comprising: a chuck body defining a substrate supporting surface; a mandrel positionable above the chuck body; a rotary drive mechanism coupled to the spindle; a terminal effector coupled to the lower end of the spindle; an electrical contact extending from the chuck body; as well as A current source is provided, wherein the current source is configured to provide current to an electrolyte within an open interior defined by a fixed wall extending from the chuck body.

9. The substrate electrochemical planarization device according to claim 8, wherein: The end effector includes a conductive material.

10. The substrate electrochemical planarization device according to claim 8, further comprising: An edge ring is disposed on the chuck body, wherein an inner diameter of the edge ring is less than about 5% greater than a diameter of the substrate supporting surface.

11. The substrate electrochemical planarization device according to claim 8, further comprising: a fixed wall, disposed radially outside the chuck body, wherein the fixed wall is annular; and The diameter of the end effector is smaller than the inner diameter of the fixed wall.

12. The substrate electrochemical planarization device according to claim 8, further comprising: A fixed wall, arranged radially outside the chuck body; Electrolyte source; as well as An electrolyte delivery port is fluidly coupled to the electrolyte source, the electrolyte delivery port being disposed radially inward of the fixed wall.

13. The substrate electrochemical planarization device according to claim 8, further comprising: An optical sensor is directed at the substrate support surface.

14. The substrate electrochemical planarization device according to claim 8, wherein: The substrate electrochemical planarization device is disposed in a polishing chamber, and the polishing chamber includes a face-down polishing station.

15. A method for planarizing a substrate, comprising: positioning a substrate face-up atop a substrate supporting surface of a chuck body within an open interior defined by a fixed wall extending from the chuck body; clamping the substrate to the chuck body; delivering an electrolyte to a top surface of the substrate; engaging the top surface of the substrate with an end effector coupled to a lower end of a mandrel; as well as An electric current is applied to the electrolyte.

16. The method for planarizing a substrate according to claim 15, further comprising: The mandrel is translated laterally while the end effector is rotated against the top surface of the substrate.

17. The method for planarizing a substrate according to claim 15, further comprising: The end effector is moved relative to the substrate.

18. The method for planarizing a substrate according to claim 15, wherein: A downward force of less than or approximately 2.0 psi is applied to the end effector while rotating the end effector against the top surface of the substrate.

19. The method for planarizing a substrate according to claim 15, wherein: While the end effector is rotated against the top surface of the substrate, a central axis of the end effector is offset from a central axis of the substrate.

20. The method for planarizing a substrate according to claim 15, further comprising: The electrolyte is drained from the open interior via an electrolyte drain port positioned in one or both of the chuck body and the fixed wall.

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