Maintenance method for polishing system, and related article

Abstract

To provide a method for forming a hydrophobic coating on a surface of a polishing system component by a chemical impregnation applicator 200 capable of being used to provide a CMP system component with a hydrophobic surface.SOLUTION: A method includes cleaning a surface of a polishing system component so as to remove polishing solution residues from a surface of the polishing system component, and coating a hydrophobizing chemical 204 on the surface of the polishing system component.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001]

[0001] Embodiments of the present disclosure generally relate to a chemical mechanical polishing (CMP) system used in the manufacture of semiconductor devices. Specifically, embodiments herein relate to a method of maintaining a hydrophobic component surface in a CMP system and related hydrophobic applicator articles.

Background Art

[0002]

[0002] In the manufacture of semiconductor devices, chemical mechanical polishing (CMP) is commonly used to planarize or polish a material layer deposited on a substrate surface. In a typical CMP process, the substrate is held by a substrate carrier, which presses the back side of the substrate against a rotating polishing pad in the presence of a polishing liquid. Generally, the polishing liquid includes an aqueous solution of one or more chemical components and nanoscale polishing particles suspended in the aqueous solution. Through the combination of the chemical activity and mechanical action imparted by the polishing liquid and the relative movement of the substrate and the polishing pad, the material of the entire surface of the material layer of the substrate in contact with the polishing pad is removed.

[0003]

[0003] CMP is generally considered a wet process, and the accumulation of undesirable by-products of the polishing liquid dried on the surface within the wet environment of the CMP system is almost inevitable. Usually, this accumulation includes accumulated polishing particles left after the spray droplets of the polishing liquid from the CMP process dry on the system surface. Unlike the individual nanoscale polishing particles suspended in a carefully formulated polishing liquid, an aggregate of dried polishing particles can cause severe damage to the substrate surface when it comes into contact with the substrate during the CMP process. This damage often appears as scratches (e.g., micro-scratches) on the substrate surface, which can have an adverse effect on the performance of the device formed thereon, or in some cases, may render the device inoperable.

[0004]

[0004] Therefore, there is a need in the art for articles and related methods to solve the above problems.

Summary of the Invention

[0005]

[0005] This disclosure generally relates to a chemical impregnation applicator that can be used to provide a hydrophobic surface to CMP system components, and related coating methods.

[0006]

[0006] In one embodiment, a method of forming a hydrophobic coating on a surface of a polishing system component is provided. The method includes cleaning the surface of the polishing system component to remove polishing fluid residues from the surface of the polishing system component, and applying a hydrophobizing chemical solution to the surface of the polishing system component.

[0007]

[0007] In another embodiment, a method of forming a hydrophobic coating on a surface of a polishing system component is provided. The polishing system component is disposed within a substrate processing environment of a polishing system. The method includes cleaning the surface of the polishing system component to remove polishing fluid residues from the surface of the polishing system component, and applying a hydrophobizing chemical solution to the surface of the polishing system component. In some embodiments, the hydrophobizing chemical solution is applied to the surface of the polishing system component without moving the polishing system component out of the substrate processing environment.

[0008]

[0008] In another embodiment, a hydrophobic applicator is provided. The hydrophobic applicator generally includes an applicator article formed of an open-cell foam material having a porosity of about 60% or more, and a hydrophobizing chemical solution. In some embodiments, both the applicator and the hydrophobizing chemical solution are packaged in a sealed container.

[0009]

[0009] To enable a more detailed understanding of the features of the present disclosure described above, the present disclosure summarized above will be described more specifically with reference to embodiments, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings merely show typical embodiments of the present disclosure and should not be considered as limiting the scope of the present disclosure, which may admit other equally effective embodiments.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

[0011]

[0020] For ease of understanding, the same reference numbers are used, wherever possible, to indicate the same elements common to the drawings. It is contemplated that the elements and features of one embodiment may be beneficially incorporated into other embodiments without further elaboration.

DETAILED DESCRIPTION OF THE INVENTION

[0012]

[0021] Embodiments of the present disclosure generally relate to articles for use in maintaining a chemical mechanical polishing (CMP) system. Specifically, embodiments herein relate to hydrophobic applicators that can be used to provide a hydrophobic surface to CMP system components, and related methods.

[0013]

[0022] Typical polishing liquids used in the CMP process can include an aqueous solution of one or more chemical components, along with nanoscale polishing particles suspended in the aqueous solution. Generally, the dry residue of the polishing liquid, such as an aggregate of polishing particles, accumulates on a component surface that is disposed above the polishing pad or otherwise proximate to the polishing pad during the polishing process. For example, the dry residue of the polishing liquid often accumulates on the surface of CMP system components such as a substrate carrier, a pad conditioner assembly, or a fluid supply arm that is disposed on the polishing pad when the polishing liquid is dispensed thereon. If the accumulated residue is not removed, aggregates of the polishing particles can flake off from the component surface onto the polishing pad and then cause undesirable damage (e.g., scratches) to the material surface of the substrate being polished thereon. Removing the accumulated residue is generally laborious and time-consuming. The accumulated polishing particles often form a cement-like layer on the component surface, resulting in an undesirable consequence of long and frequent downtime of the polishing system for consumable replacement and preventive maintenance (PM) procedures.

[0014]

[0023] Generally, the surface of the polishing components exposed to the spray droplets of the polishing liquid is formed of a material having chemical resistance and / or corrosion resistance to the polishing liquid. In some embodiments, the surface can be formed of a hydrophobic material and / or can have a hydrophobic coating such that the droplets of the polishing liquid flow off the component surface more easily before drying and forming an undesirable polishing liquid residue thereon. Unfortunately, the delicate liquid-surface interface that provides the hydrophobicity of such materials and / or coatings has limitations in durability. Thus, in a typical CMP processing environment, the hydrophobicity of the surface of the CMP components can significantly degrade well before the end of the useful life of those components. For example, the periodic maintenance procedures for cleaning the polishing liquid residue from the CMP components, and the materials used therefor, such as polishing pads, corrosive chemicals, and the particles of the accumulated polishing liquid residue, often abrade the component surface and thus reduce its hydrophobicity. As the surface of the component wears, its ability to repel the droplets of the polishing liquid decreases, and thus the rate at which the polishing liquid residue accumulates thereon increases. Accordingly, the embodiments herein beneficially provide a method for periodically restoring the hydrophobicity of the CMP component surface and a hydrophobic applicator that can be used to implement the method. As used herein, the hydrophobic applicator is packaged such that both the applicator article and the hydrophobizing solution are included in a single-use packaging container so as to avoid the general restrictions regarding the storage and transport of liquid containers within the substrate processing portion of semiconductor device manufacturing equipment.

[0015]

[0024] In some embodiments, the method includes treating a component surface during a CMP consumable replacement procedure. CMP consumables generally include articles used in a CMP process, which have a limited service life due to wear associated with substrate processing and thus need to be replaced periodically depending on the number of substrates processed thereon or therewith, or the cumulative substrate processing time. Examples of CMP consumables include polishing pads, pad conditioning disks, and some components of a substrate carrier. The method generally includes cleaning any polishing liquid residue accumulated from the CMP component surface and then treating the component surface to restore its hydrophobicity. The newly restored hydrophobic surface beneficially reduces the amount of polishing liquid residue that may accumulate on the component surface during consumable replacement or other maintenance procedures, and as a result, beneficially reduces the associated cleaning time and labor. An exemplary polishing system that can benefit from the embodiments described herein is shown in FIG. 1A.

[0016]

[0025] FIG. 1A is a schematic side view of an exemplary polishing system 100 that can benefit from the applicator and related methods provided herein, according to one embodiment. FIG. 1B is a schematic cross-sectional view of a portion of a substrate carrier assembly 104 used with the polishing system 100 of FIG. 1A, according to one embodiment.

[0017]

[0026] Typically, the polishing system 100 features a frame (not shown) and a plurality of panels 101, by which a substrate processing environment 103 is defined. The polishing system 100 includes a plurality of polishing stations 102 (one shown) and a plurality of substrate carrier assemblies 104 (one shown) disposed within the substrate processing environment 103.

[0018]

[0027] As shown in FIG. 1A, the polishing station 102 includes a platen 106, a polishing pad 108 attached to and fixed to the platen 106, a pad conditioner assembly 110 for cleaning and / or regenerating the polishing pad, and a fluid supply arm 112 for dispensing a polishing fluid onto the polishing pad 108. As used herein, the platen 106 is disposed above a base plate 114 and circumscribed by a platen shield 120 (both shown in cross section), and together they define a drainage area 116. The drainage area 116 is used to collect fluid spun radially outward from the platen 106 and discharge the fluid through a drainage basin 118 that is fluidly connected thereto.

[0019]

[0028] The pad conditioner assembly 110 is used to clean and / or regenerate the polishing pad 108 by sweeping away polishing by-products therefrom with a brush (not shown) or the like and / or by pressing a polishing pad conditioner disk 124 (e.g., a diamond-impregnated disk) against the polishing pad 108 to polish the polishing pad 108. The pad conditioning process can be performed during the polishing of the substrate, i.e., off-site conditioning, simultaneously with the polishing of the substrate, i.e., in-situ conditioning, or both.

[0020]

[0029] As used herein, the pad conditioner assembly 110 includes a first actuator 126 disposed on a base plate 114, a conditioner arm 128 coupled to the first actuator 126, and a conditioner mounting plate 130 having a conditioner disk 124 fixedly coupled thereto. The first end of the conditioner arm 128 is coupled to the first actuator 126, and the mounting plate 130 is coupled to the second end of the conditioner arm 128 that is distal from the first end. The first actuator 126 is used to sweep the conditioner arm 128, and thus the conditioner disk 124, about an axis C such that the conditioner disk 124 vibrates between the inner diameter and the outer diameter of the polishing pad 108 while the polishing pad 108 rotates thereunder. In some embodiments, the pad conditioner assembly 110 further includes a second actuator 132 disposed on and coupled to the second end of the conditioner arm 128, and the second actuator 132 is used to rotate the conditioner disk 124 about an axis D. Typically, the mounting plate 130 is coupled to the second actuator 132 using a shaft 134 disposed therebetween.

[0021]

[0030] Generally, the rotating substrate carrier assembly 104 reciprocates from the inner diameter to the outer diameter of the platen 106 while the platen 106, and thus the polishing pad 108, rotates about the platen axis B thereunder. The polishing fluid is supplied to the polishing pad 108 using a fluid supply arm 112 positioned thereabove, and is further supplied to the polishing interface between the polishing pad 108 and the substrate 122 by the rotation of the polishing pad 108 about the platen axis B. Often, the fluid supply arm 112 further includes a plurality of nozzles (not shown) that can be used to supply a relatively high pressure stream of cleaning fluid, such as deionized water, to the polishing pad 108.

[0022]

[0031] As shown in FIG. 1B, the substrate carrier assembly 104 features a carrier head 140, a carrier ring assembly 142 coupled to the carrier head 140, and a flexible membrane 148 disposed radially inwardly of the carrier ring assembly 142 to provide a mounting surface for the substrate 122. The carrier ring assembly 142 includes a lower annular portion and an upper annular portion, which are the substrate holding ring 144 and the backing ring 146 respectively herein. The substrate holding ring 144 is typically formed of a polymer bonded to the backing ring 146 using a bonding layer (not shown) disposed therebetween. The backing ring 146 is formed of a rigid material such as metal or ceramic and is fixed to the carrier head 140 using a plurality of fasteners (not shown). Examples of suitable materials used to form the substrate holding ring 144 and the backing ring 146 respectively include any one or a combination of the abrasive liquid resistant polymers, metals, and / or ceramics described herein. The flexible membrane 148 is typically coupled to the carrier head 140 using one or more annular membrane clamps 150 and collectively defines a region 152 therein.

[0023]

[0032] During substrate processing, the substrate holding ring 144 surrounds the substrate 122 to prevent the substrate 122 from slipping off the substrate carrier assembly 104. Typically, while the substrate carrier assembly 104 rotates about the carrier axis A, the region 152 is pressurized during polishing such that the flexible membrane 148 exerts a downward force on the substrate 122, thus pressing the substrate 122 against the polishing pad 108. Before and after polishing, a vacuum is applied to the region 152 to deflect the flexible membrane 148 upward to create a low-pressure pocket between the flexible membrane 148 and the substrate 122, thereby vacuum chucking the substrate 122 to the substrate carrier assembly 104.

[0024]

[0033] Generally, the inner diameter of the substrate holding ring 144 is larger than the diameter of the substrate 122 so that there is a certain margin during the polishing process and the substrate loading and unloading operations, for example, exceeding about 2 mm, or exceeding about 3 mm, etc. Similarly, the outer diameter of the substrate mounting surface of the flexible film 148 is smaller than the inner diameter of the substrate holding ring 144 so that the flexible film 148 can move relative thereto. A gap G is created due to the margin between the substrate 122 and the substrate holding ring 144, and between the flexible film 148 and the substrate holding ring 144. Often, polishing liquid enters the gap G, and polishing liquid residues may be formed on one or more surfaces therein, such as one or both of the radially inward surfaces of the substrate holding ring 144 and the backing ring 146, and one or more radially outward surfaces of the annular film clamp 150. In some embodiments, the substrate carrier assembly 104 further includes a head cover 154 disposed on the carrier head 140.

[0025]

[0034] In this specification, one or more surfaces of the polishing system 100, and / or its components, for example, the surfaces of the pad conditioner assembly 110, the platen shield 120, and the substrate carrier assembly 104, are treated using the hydrophobic applicator and / or spraying method described herein to prevent and / or greatly reduce the accumulation of polishing liquid residues thereon.

[0026]

[0035] Figure 2 is a schematic isometric view of a hydrophobic applicator 200 according to one embodiment that can be used with the methods described herein. As used herein, the hydrophobic applicator 200 includes an applicator article 202 impregnated with a hydrophobizing chemical solution 204. In this embodiment, the applicator article 202 is formed of a fiber-free foaming material, such as a polyvinyl alcohol (PVA) or polyurethane (PU) foaming material suitable for use in a cleanroom environment of a semiconductor device manufacturing facility. Generally, the foaming material used to form the applicator article 202 has an open cell pore structure and a porosity of about 60% or more, such as about 65% or more, about 70% or more, about 75% or more, about 80% or more, or about 90% or more. In some embodiments, the foaming material used to form the applicator article 202 is about 50 kg / m 3 or more, such as about 60 kg / m 3 or more, about 70 kg / m 3 or more, such as about 80 kg / m 3 or more in density. In some embodiments, the applicator article 202 is soft and flexible at room temperature and thus typically has a glass transition temperature (Tg) of about 25°C or less, such as about 20°C or less, about 15°C or less, or for example about 10°C or less. One or both of the pore size and density may vary throughout the applicator article 202 (as shown) or one or both of the pore size and density may be uniformly distributed throughout. In other embodiments, the applicator article 202 may be formed of a suitable fibrous synthetic material, such as a polyester cloth.

[0027]

[0036] In this specification, the hydrophobic chemical solution 204 includes one of a solution, a mixture, and / or an emulsion characterized by a solvent and a hydrophobizing agent. In some embodiments, the hydrophobic chemical solution 204 further includes a surfactant such as a carboxylic acid-based component. Examples of suitable solvents include hydrocarbon solvents, fluorine-based solvents, or combinations thereof. In some embodiments, the fluorine-based solvent is a hydrofluoroether (HFE)-based solvent such as 2-trifluoromethyl-3-ethoxydodecafluorohexane. Examples of suitable hydrophobizing agents include monomers, oligomers, and / or other functional groups of siloxane, fluoroacrylate, or combinations thereof. Examples of suitable fluorinated acrylic monomers include pentafluorophenyl acrylate, hexafluoroisopropyl methacrylate; 1H,1H,3H-hexafluorobutyl methacrylate; 2,2,2-trifluoroethyl acrylate; 2,2,2-trifluoroethyl methacrylate; 1H,1H,2H,2H-heptadecafluorodecyl methacrylate (HDFDMA); 1H,1H,5H-octafluoropentyl methacrylate; and combinations thereof. The carboxylic acid-based component may be a carboxylic acid, a carboxylate, a carboxylic acid derivative, or combinations thereof.

[0028]

[0037] In this specification, before or simultaneously with being packaged in a sealed container 206 (shown in partial cross-section) to prevent exposure of the hydrophobic applicator 200 to the atmosphere, the applicator article 202 is impregnated with a hydrophobizing chemical solution 204. The container 206 can be formed of any suitable material generally accepted for use in a cleanroom environment, such as an antistatic polyethylene material. Generally, the packaged applicator article 202 is not completely saturated with the hydrophobizing chemical solution 204 in order to provide improved control over the thickness of the hydrophobic coating formed during the coating methods described herein. For example, if X represents the maximum amount by weight of the hydrophobizing chemical solution 204 that can be absorbed by the applicator article 202, the packaged applicator article 202 can have an actual saturation by weight of about 0.9X or less, such as about 0.8X or less, about 0.7X or less, about 0.6X or less, about 0.5X or less, or about 0.4X or less. In some embodiments, the packaged applicator article 202 has an actual saturation by weight of the hydrophobizing chemical solution 204 in the range of about 0.1X to about 0.5X, such as about 0.2X to about 0.5X, or about 0.3X to about 0.5X. In some embodiments, the packaged applicator article 202 has an actual saturation by weight of the hydrophobizing chemical solution 204 in the range of about 0.5X to about 0.9X, such as about 0.6X to about 0.9X, or about 0.7X to about 0.9X. In some embodiments, the packaged applicator article 202 has an actual saturation by weight of the hydrophobizing chemical solution 204 in the range of about 0.2X to about 0.8X, such as about 0.3X to about 0.7X, or about 0.4X to about 0.5X.

[0029]

[0038] Figure 3 is a schematic isometric view of a hydrophobic applicator 300 according to another embodiment that can be used with the method described herein. In this specification, the container 306 (shown in partial cross-section) is substantially similar to the container 206 described in FIG. 2 and further includes an impermeable membrane 308 that divides the container 306 into a first region 310 and a second region 312. The applicator article 302 and the hydrophobizing chemical solution 204 are disposed in the first region 310 and the second region 312, respectively, and are thus separated by the membrane 308. Prior to the method described herein, by the user operating the container 306 to break the membrane 308, the hydrophobizing chemical solution 204 can be absorbed by the surface of the applicator article 302 and / or coat the surface of the applicator article 302 to form the hydrophobic applicator 300. In this specification, the applicator article 302 is substantially similar to or the same as the applicator article 202 described in FIG. 2. Typically, the amount of the hydrophobizing chemical solution 204 disposed in the second region 312 is selected to provide a desired actual saturation of the applicator article 302 by the hydrophobizing chemical solution 204 when the membrane 308 is ruptured. In some embodiments, the desired actual saturation of the applicator article 302 is within the same range as described for the actual saturation of the applicator article 202 described in FIG. 2.

[0030]

[0039] Figure 4A is a schematic isometric view of a hydrophobic applicator 400 according to another embodiment that can be used with the method described herein. The hydrophobic applicator 400 includes an applicator article 402 impregnated with the hydrophobizing chemical solution 204. In this specification, the applicator article 402 is sized and shaped to apply the hydrophobizing chemical solution 204 to the surface of the pad conditioner assembly 110, such as the conditioner mounting plate 130 and the surface of the second actuator 132 in FIG. 1A, and the surfaces disposed therebetween.

[0031]

[0040] The applicator article 402 includes a cylindrical disk having a diameter that is approximately the same as or greater than the diameter of the conditioner mounting plate 130, a thickness that is approximately the same as or less than the distance between the mounting plate 130 and the second actuator 132, and an opening 406 sized to fit around the shaft 134. For example, in some embodiments, the applicator article 402 has a diameter of about 100 mm or more, such as about 150 mm or more, or about 200 mm or more, or from about 100 mm to about 300 mm, and a thickness of about 50 mm or less, such as about 40 mm or less, or about 30 mm or less, or from about 10 mm to about 50 mm. The generally circular opening 406 is disposed through the center (or proximate thereto) of the cylindrical disk and has a diameter that is approximately the same as or slightly smaller than the diameter of the shaft 134. For example, in some embodiments, the diameter of the opening 406 is from about 10 mm to about 30 mm, such as from about 10 mm to about 20 mm. The slit 408 connects the opening 406 to the outer periphery of the applicator article 402 so that the applicator article 402 can be positioned around the shaft 134 without removing the mounting plate 130 from the pad conditioner assembly 110.

[0032]

[0041] In some embodiments, the material used to form the applicator article 402 is substantially similar to or the same as the material used to form the applicator article 202 described in FIG. 2. The applicator article 402 and the hydrophobizing chemical solution 204 can each be packaged using either of the containers 206 and 306 described in FIGS. 2 and 3. In some embodiments, the actual or desired actual saturation of the applicator article 402 is within the same range as that described for the actual saturation of the applicator article 202 described in FIG. 2.

[0033]

[0042] Figure 4B is a schematic isometric view further showing a clamp 412 that can be used with a hydrophobic applicator 400 according to some embodiments. As shown in Figure 4B, the clamp 412 secures the edge of the hydrophobic applicator 400 and provides an ergonomic handle to the user to facilitate the methods described herein. The clamp is typically formed of a non-rigid or semi-rigid material, such as a non-rigid or semi-rigid polymer, rubber, or synthetic rubber material, having suitable chemical resistance to the polishing fluid and enabling a gripping strength to hold the hydrophobic applicator 400 in place during the methods described herein. In some embodiments, the material used to form the clamp 412 has a Shore A hardness in the range of about 60 to about 85.

[0034]

[0043] Figure 5 is a schematic isometric view of a hydrophobic applicator 500 according to another embodiment that can be used with the methods described herein. The hydrophobic applicator 500 includes an applicator article 502 impregnated with a hydrophobizing chemical solution 204. In some embodiments, the material used to form the applicator article 502 is substantially similar to or the same as the material used to form the applicator article 202 described in Figure 2. In some embodiments, the actual or desired actual saturation of the applicator article 502 with the hydrophobizing chemical solution 204 is equal to or within the same range as that described for the actual saturation of the applicator article 202 described in Figure 2.

[0035]

[0044] As used herein, the applicator article 502 is secured to a fastener layer, such as a first fastener layer 508, by the use of an adhesive 506. In some embodiments, the first fastener layer 508 includes a part of a surface fastener system, which can be used to attach the hydrophobic applicator 500 to an applicator device 600 described in Figure 6. The applicator article 502 to which the first fastener layer 508 is secured and the hydrophobizing chemical solution 204 can each be packaged using either of the containers 206 or 306 described in Figures 2 and 3.

[0036]

[0045] FIG. 6 is a schematic side view of a portion of a polishing system 100 showing an applicator device 600 that can be used with the methods described herein to apply a hydrophobic chemical solution 204 to a portion of a platen shield 120. Typically, applicator device 600 is used during a polishing pad exchange procedure to press a hydrophobic applicator 500 against the radially inward surface of platen shield 120, and thus is used to apply a layer of hydrophobic chemical solution 204 thereto. For example, in FIG. 6, applicator device 600 is temporarily coupled to the peripheral edge of platen 106 using a clamp 602 disposed thereon and / or a fastener 604 (shown in dashed lines) disposed in a corresponding opening in the radially outward surface of platen 106.

[0037]

[0046] As used herein, applicator device 600 includes an applicator attachment portion 606 and a fastener layer such as a second fastener layer 608 that includes a second portion of a surface fastener system. The second fastener layer 608 is secured to the surface of the applicator attachment portion 606 by use of an adhesive, and the hydrophobic applicator 500 is temporarily secured to the applicator attachment portion 606 by use of a surface fastener system. Generally, applicator device 600 further includes an elastic member 610, such as a spring, that is used to press the hydrophobic applicator 500 against the radially inward surface of platen shield 120 when platen 106 rotates about platen axis B (shown in FIG. 1A). Applicator device 600 advantageously enables the methods described herein without requiring the time-consuming procedure of removing the platen shield 120 from the polishing system 100, thereby reducing the undesirable downtime of the system for periodic maintenance.

[0038]

[0047] FIG. 7 is a diagram showing a method 700 for applying a hydrophobic coating to a surface of a polishing system component, such as a component of the polishing system 100 of FIG. 1A, according to one embodiment. Typically, method 700 is performed during polishing system downtime in a periodically scheduled maintenance procedure, such as a consumable replacement procedure or a preventive maintenance (PM) procedure.

[0039]

[0048] FIG. 8 is a schematic cross-sectional view of a portion of a polishing system component 800 used to illustrate various aspects of method 700. As used herein, polishing system component 800 represents any component of polishing system 100 and / or other surfaces that can be exposed to atomized droplets of polishing fluid during a substrate polishing process. For example, polishing system component 800 can be any one of panel 101, substrate carrier assembly 104, components of pad conditioner assembly 110, fluid supply arm 112, platen 106 and / or its peripheral surfaces, platen shield 120, or any other surface or component used with and / or disposed within substrate processing environment 103 of polishing system 100. Generally, system component 800 and / or its pre-application surface 802 are formed of a polishing fluid chemical resistant material. Examples of suitable materials include silica glass, quartz, ceramics such as alumina, polishing fluid chemical resistant metals, and polishing fluid chemical resistant polymers. Examples of suitable metals include stainless steel alloys, nickel-chromium alloys, nickel-chromium-molybdenum alloys, nickel-iron-chromium-molybdenum alloys, cobalt-nickel-chromium-molybdenum alloys, and titanium alloys. Examples of suitable polymers include polyphenylene sulfide (PPS), polyethylene terephthalate (PET), polyether ether ketone (PEEK), polyimide (PI) and polybutylene terephthalate (PBT), acetal polyoxymethylene (POM), polyamideimide (PAI), polytetrafluoroethylene (PTFE), polybenzimidazole (PBI), polyetheramine (PEI), and composites thereof.

[0040]

[0049] In operation 705, method 700 includes removing polishing fluid residue from the surface of a polishing system component, such as pre-application surface 802. Typically, removing polishing fluid residue from a component includes pressing a cleaning article, such as a sponge or cloth, against pre-application surface 802 in the presence of a cleaning fluid. In some embodiments, the cleaning article may have a polishing surface. Generally, the cleaning fluid is selected based on the type of polishing fluid used with exemplary polishing system 100 and the suitability of the cleaning fluid to dissolve residual deposits of that polishing fluid. Examples of suitable cleaning fluids include dilute solutions of hydrogen peroxide, ammonium hydroxide, and various acids such as citric acid. In some embodiments, the cleaning fluid may include a dilute aqueous solution having at least a portion of the same components used in the polishing fluid. For example, if the polishing fluid includes potassium hydroxide, the cleaning fluid may include an aqueous solution of potassium hydroxide. In some embodiments, the cleaning fluid is deionized water. In some embodiments, the cleaning fluid includes a surfactant. In some embodiments, removing the polishing fluid residue also removes a portion of a hydrophobic coating applied during a previous consumable replacement or preventive maintenance procedure. Generally, after removing the polishing fluid residue from polishing system component 800, pre-application surface 802 is rinsed with deionized water and dried, for example, by blowing clean dry air (CDA) onto the surface.

[0041]

[0050] In operation 710, method 700 includes applying a hydrophobic chemical solution, such as hydrophobic chemical solution 204 described herein, to the pre-application surface 802 of a polishing system component. As used herein, applying hydrophobic chemical solution 204 to pre-application surface 802 forms a hydrophobic coating 804 having a post-application surface 806. As used herein, a water droplet 808 disposed on the system component forms a contact angle θ with post-application surface 806 that is about 60° or greater, about 65° or greater, about 70° or greater, about 75° or greater, about 80° or greater, about 85° or greater, about 90° or greater, about 95° or greater, about 100° or greater, about 105° or greater, or for example about 110° or greater. In some embodiments, hydrophobic coating 804 has a thickness T that is about 100 μm or less, for example, about 85 μm or less, about 80 μm or less, about 75 μm or less, about 70 μm or less, about 65 μm or less, about 60 μm or less, about 55 μm or less, or about 50 μm or less.

[0042]

[0051] As described herein, due to wear and corrosion of pre-application surface 802 by repeated exposure to the polishing liquid and cleaning of polishing liquid residues therefrom, the hydrophobicity of pre-application surface 802 tends to decrease over the service life of system component 800. Thus, in some embodiments, pre-application surface 802 may have a water contact angle that is about 100° or less, for example, about 95° or less, about 90° or less, about 85° or less, about 80° or less, about 75° or less, about 70° or less, about 65° or less, about 60° or less, about 55° or less, or about 50° or less. In some embodiments, applying hydrophobic chemical solution 204 provides a beneficial increase in hydrophobicity of about 10% or greater, for example about 15% or greater, about 20% or greater, about 25% or greater, about 30% or greater, about 35% or greater, about 40% or greater, about 45% or greater, about 50% or greater, about 65% or greater, about 70% or greater, for example about 75% or greater. As used herein, the increase in hydrophobicity is determined using the difference in the water droplet contact angle θ between pre-application surface 802 and post-application surface 806.

[0043]

[0052] In some embodiments, the hydrophobic coating 804 formed on the surface of the system component 800 exhibits oleophobic surface properties and has high resistance to non-aqueous contaminants such as dust, oil, and / or other fine particles. Thus, in some embodiments, the hydrophobic coating 804 has an oil contact angle of about 50° or more, such as about 55° or more, about 60° or more, about 65° or more, such as about 70° or more, herein referred to as the n-hexadecane droplet contact angle. The n-hexadecane droplet contact angle is measured with respect to the surface 806 after application, as shown by the water droplet contact angle θ in FIG. 8.

[0044]

[0053] In some embodiments, applying the hydrophobizing chemical solution 204 to the system component 800 includes rubbing or pressing an applicator article impregnated with the hydrophobizing chemical solution 204 against the pre-application surface 802. For example, in some embodiments, the method 700 can be performed using any one of the hydrophobic applicators 200, 300, 400, and / or 500 described herein.

[0045]

[0054] In some embodiments of the method 700, the hydrophobizing chemical solution is applied to the surface of the polishing system component without moving the polishing system component from the substrate processing environment. For example, in some embodiments, the system component 800 includes a platen shield 120, and the hydrophobizing chemical solution 204 is applied to the radially inward surface of the platen shield 120 using the applicator device 600 described in FIG. 6. In those embodiments, applying the hydrophobizing chemical solution 204 can include rotating the polishing platen 106 and thus the applicator device 600 coupled thereto to press the hydrophobic applicator 500 against the radially inward surface of the platen shield 120.

[0046]

[0055] In other embodiments, the system component 800 includes components of the pad conditioner assembly 110, such as the first actuator 126, the conditioner arm 128, the conditioner mounting plate 130, the second actuator 132, the shaft 134, or combinations thereof. In those embodiments, applying the hydrophobic chemical solution 204 may include sliding the hydrophobic applicator 400 into a gap disposed between the conditioner mounting plate 130 and the second actuator 132 such that the shaft 134 is disposed through the opening 406 before moving the hydrophobic applicator 400 around the shaft 134.

[0047]

[0056] In another embodiment, the hydrophobic coating 804 may be applied to the surface of the system component 800 after the system component 800 has been moved from the substrate processing environment 103. In some embodiments, the hydrophobic coating 804 is applied to the pre-application surface 802 of the system component 800 using a spraying method that generates droplets of the hydrophobic chemical solution 204 and exposes the pre-application surface 802 thereto, herein referred to as a "spray process". Examples of suitable spray processes include ultrasonic spraying using an ultrasonic nozzle, pressure spraying, and electrospraying.

[0048]

[0057] A typical ultrasonic spray process involves operating an ultrasonic nozzle to convert high-frequency sound waves into mechanical energy transmitted to a liquid, such as a hydrophobizing chemical solution 204, and spraying the liquid as it exits the orifice of the nozzle. The ultrasonic nozzle is configured to operate at a resonant frequency that determines the median droplet size of the droplets provided therefrom. Generally, an ultrasonic nozzle operating at a high frequency provides a relatively small median droplet size compared to an ultrasonic nozzle operating at a low frequency. In one embodiment, the hydrophobizing chemical solution 204 is applied using an ultrasonic nozzle operating at a frequency in the range of 10 kHz to about 200 kHz, such as about 200 kHz or less, about 190 kHz or less, about 180 kHz or less, about 170 kHz or less, about 160 kHz or less, about 150 kHz or less, about 140 kHz or less, about 130 kHz or less, about 120 kHz or less, about 110 kHz or less, about 100 kHz or less, about 90 kHz or less, about 80 kHz or less, about 70 kHz or less, about 60 kHz or less, about 50 kHz or less, about 40 kHz or less, such as about 30 kHz or less. In some embodiments, the ultrasonic nozzle operates at a frequency of about 10 kHz or more, such as about 20 kHz or more, about 30 kHz or more, about 40 kHz or more, about 50 kHz or more, about 60 kHz or more, about 70 kHz or more, about 80 kHz or more, about 90 kHz or more, about 100 kHz or more, about 110 kHz or more, about 120 kHz or more, about 130 kHz or more, about 140 kHz or more, such as about 150 kHz or more.

[0049]

[0058] The pressurized spray process generally involves providing an aerosol mist of the hydrophobizing chemical solution 204 using a propellant under pressure and exposing the pre-coated surface 802 of the system component 800 thereto.

[0050]

[0059] In the electrospray process, a relatively high voltage of about 1000 V or more is applied to the electrospray nozzle to charge a liquid, such as a hydrophobic chemical solution 204, with static electricity. Due to this static electricity charging, the fluid is sprayed into fine droplets by the electrostatic repulsive force. Generally, the system component 800 to be coated is disposed on a grounded stage, whereby the charged droplets are attracted to its surface. Advantageously, by using the electrostatic spray process, a substantially uniform hydrophobic coating 804 can be obtained over the entire system component 800 having a relatively uneven surface.

[0051]

[0060] In some embodiments, the various steps of method 700 can be used during the modification of system component 800, such as during the modification of substrate carrier assembly 104. In one embodiment, method 700 includes removing the substrate carrier assembly 104, removing the polishing liquid residue accumulated on the surface of its components, and applying a coating of hydrophobic coating 804 thereto using one or a combination of hydrophobic applicators 200, 300, 400, or 500 and / or a spray process. Thus, in some embodiments, the hydrophobic coating 804 is applied to the surface of the carrier ring assembly 142, such as the inner diameter and outer diameter, the carrier head 140, the head cover 154, and the surface of one or more annular film clamps 150 that may be exposed to the polishing liquid during the polishing process. In some embodiments, at least some of the system components are new, and thus, method 700 may not include removing the polishing liquid residue therefrom.

[0052]

[0061] Advantageously, the methods 700 and / or the hydrophobic applicators 200, 300, 400, and / or 500 described herein facilitate the application of the hydrophobic coating 804 onto the surface of the system component 800. The hydrophobic coating 804 reduces the amount of abrasive residue that may accumulate on the component surface during consumable replacement and other maintenance procedures, generally provides a clean system, and reduces substrate processing defects such as surface scratches associated with excessive residue accumulation. By reducing the amount of abrasive residue accumulation on the component surface, the methods and articles provided herein beneficially reduce the labor and time required to clean those residues and beneficially extend the service life of the system components. In some embodiments, the method may be performed at a location remote from the polishing system 100, such as during the modification (retrofitting) of the substrate carrier assembly 104. In other embodiments, the method 700 may be performed without removing the polishing system component 800 from the substrate processing environment 103. By applying a hydrophobic coating onto the system component without removing and / or moving the component from the substrate processing environment, the labor, time, and cost that may occur when removing the system component from the polishing system can also be beneficially reduced.

[0053]

[0062] While the foregoing is directed to embodiments of the present disclosure, it is possible to devise other additional embodiments of the present disclosure without departing from its basic scope as determined by the following claims.

Claims

1. A method of forming a hydrophobic coating on a surface of a polishing system component, comprising: cleaning the surface of the polishing system component to remove polishing liquid residues from the surface of the polishing system component; and applying a hydrophobizing chemical solution to the surface of the polishing system component.

2. The method according to claim 1, wherein the polishing system component is part of a substrate carrier assembly, and the hydrophobizing chemical solution is applied using a spray process.

3. The hydrophobizing chemical solution is applied using a hydrophobic applicator, the hydrophobic applicator comprising: an applicator article formed of an open-cell foam material having a porosity of about 60% or more; and the hydrophobizing chemical solution. The method according to claim 1.

4. The method according to claim 3, wherein the applicator and the hydrophobizing chemical solution are packaged in a sealed container.

5. The method according to claim 4, wherein the applicator article disposed in the sealed container is impregnated with the hydrophobizing chemical solution.

6. The method according to claim 4, wherein the sealed container includes a membrane layer that separates the applicator article from the hydrophobizing chemical solution, and further includes breaking the membrane to impregnate the applicator article with the hydrophobizing chemical solution.

7. The polishing system component includes a platen shield, the hydrophobic applicator is coupled to a polishing platen, and applying the hydrophobizing chemical solution includes rotating the polishing platen so as to press the hydrophobic applicator against a radially inward surface of the platen shield. The method according to claim 3.

8. The polishing system component is disposed within a substrate processing environment of the polishing system, and the hydrophobizing chemical solution is applied to the surface of the polishing system component without moving the polishing system component out of the substrate processing environment. The method according to claim 3.

9. The polishing system component includes a conditioner mounting plate having a first surface for mounting a polishing pad conditioning disk and a second surface opposite the first surface, and the hydrophobizing chemical solution is applied to the second surface without removing the conditioner mounting plate from a pad conditioner assembly. The method according to claim 8. A method of forming a hydrophobic coating on a surface of a polishing system component, comprising: Cleaning the surface of the polishing system component to remove polishing liquid residues from the surface of the polishing system component; Applying a hydrophobizing chemical solution to the surface of the polishing system component, wherein the polishing system component is disposed within a substrate processing environment of the polishing system, and the hydrophobizing chemical solution is applied to the surface of the polishing system component without moving the polishing system component out of the substrate processing environment; applying a hydrophobizing chemical solution to the surface of the polishing system component A method comprising: **Claim 11** The hydrophobizing chemical solution is applied using a hydrophobic applicator, and the hydrophobic applicator An applicator article formed of an open-cell foam material having a porosity of about 60% or more; The hydrophobizing chemical solution; The method according to claim 10, comprising: **Claim 12** A hydrophobic applicator, comprising: An applicator article formed of an open-cell foam material having a porosity of about 60% or more; A hydrophobizing chemical solution; The hydrophobic applicator, wherein the applicator and the hydrophobizing chemical solution are packaged in a sealed container. **Claim 13** The hydrophobic applicator according to claim 12, wherein the applicator article disposed in the sealed container is impregnated with the hydrophobizing chemical solution. **Claim 14** The hydrophobic applicator according to claim 12, wherein the sealed container includes a membrane layer that separates the applicator article from the hydrophobizing chemical solution. **Claim 15** The hydrophobic applicator according to claim 12, wherein the amount by weight of the hydrophobizing chemical solution in the sealed container is about 0.9X or less of the amount by weight required to completely saturate the applicator article. **Claim 16** The hydrophobic applicator according to claim 12, wherein the surface coating formed by the hydrophobizing chemical solution has a water contact angle of about 85° or more. **Claim 17** The hydrophobic applicator according to claim 12, wherein the applicator article is fixed to a fastener layer, and the fastener layer includes a part of a hook-and-loop fastener system. **Claim 18** The hydrophobic applicator according to claim 12, wherein the hydrophobizing chemical solution includes siloxane, fluoroacrylate, or a combination thereof. **Claim 19** The hydrophobic applicator according to claim 18, wherein the hydrophobizing chemical solution further includes a hydrocarbon-based solvent, a fluorine-based solvent, or a combination thereof. **Claim 20** The hydrophobic chemical solution further includes a carboxylic acid, a carboxylate, a carboxylic acid derivative, or a combination thereof, and the hydrophobic applicator according to claim 19.

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