Brush box drive roller with increased torque transmission

Abstract

A gripping member for use on a rotating substrate support in a substrate processing system is provided. The gripping member includes an annular body including an outer radial surface and an inner radial surface and a groove disposed in the outer radial surface. The groove including a first sidewall, a second sidewall, and a base surface. A downward force on a portion of the groove causes the annular body to deform such that the first sidewall and the second sidewall are moved inward towards a center of the groove.

Description

PATENTAttorney Docket No.: 44025826WO01BRUSH BOX DRIVE ROLLER WITH INCREASED TORQUE TRANSMISSIONBACKGROUNDField

[0001] Embodiments of the present invention generally relate to electronic device manufacturing, and in particular, to chemical mechanical polishing (CMP) systems and methods used in a semiconductor device manufacturing processes.Description of the Related Art

[0002] During chemical mechanical polishing (CMP) processing, scattered particles, such as Cu, Ta, W, TaN, or Ti, may accumulate on both the front surface and back surface of a substrate. To properly remove the scattered particles, most post-CMP cleaning processes include physical contact cleaning processes as one of cleaning steps. Typically, the physical contact cleaning methods largely consist of physically removing excess particles with scrubbing brushes.

[0003] Post-CMP scrubbing brushes (i.e., scrubbers) remove particles by directly contacting the brush with the substrate surface. Typical scrubber assemblies have one brush on either side of the substrate surface. The brushes are spaced apart when the substrate is received or removed from the scrubbing assembly. The brushes are brought into contact with the substrate during cleaning.

[0004] The substrate is typically supported on a roller of the scrubbing assembly. In some examples, the substrate is supported in a vertical orientation on the roller. In some instances, the roller includes a gap for receiving the substrate in the vertical orientation. In some instances, the roller is a drive roller that causes the substrate to rotate while the scrubbing brushes remove particles from the substrate surface. One challenge encountered by the scrubbing assemblies is slippage of the substrate on the roller and thus inconsistent number of rotations of each substrate relative to the scrubbing brushes at the completion of a cleaning process. For example, forces experienced by the substrate during scrubbing may cause the substrate to slip on the drive roller causing the rotation of the substrate to cease for periods of time. When the substrate ceases to rotate, scrubbing of the substrate surface may be non-uniform 8858733_2 1PATENTAttorney Docket No.: 44025826WO01and substrate-to-substrate variations will occur due to a differing exposure to the scrubbing brushes during processing of each substrate.

[0005] There is, therefore, a need for a brush cleaning unit that can reduce slippage of the substrate relative to the drive roller.SUMMARY

[0006] A gripping member for use on a rotating substrate support in a substrate processing system is provided. The gripping member includes an annular body including an outer radial surface and an inner radial surface and a groove disposed in the outer radial surface. The groove including a first sidewall, a second sidewall, and a base surface. A downward force on a portion of the groove causes the annular body to deform such that the first sidewall and the second sidewall are moved inward towards a center of the groove.

[0007] A rotating substrate support for using in a substrate processing system is provided. The rotating substrate support includes a cylindrical hub and a gripping member. The cylindrical hub includes a circumferential groove formed in an outer surface radial surface of the cylindrical hub. The gripping member is disposed in the circumferential groove. The gripping member includes a recess disposed in an outer radial surface of the gripping member for receiving a substrate. The recess includes a first sidewall, a second sidewall, and a base surface. A downward force on a portion of the recess causes the gripping member to deform such that the first sidewall and the second sidewall are moved inward to grip the substrate disposed in the recess.

[0008] A brush cleaning system for cleaning a substrate is provided. The system includes a tank, a first support and a second support coupled to the tank, a first cylindrical roller coupled to the first support, a second cylindrical roller coupled to the second support, wherein the first support and the second support are operable to move the first and second cylindrical rollers into contact with the substrate, and a drive roller coupled to the tank and operable to rotate the substrate. The drive roller includes a cylindrical hub including a circumferential groove formed in an outer surface radial surface of the hub, and a gripping member disposed in the circumferential groove. The gripping member includes a recess disposed in an outer radial surface of the8858733_2 2PATENTAttorney Docket No.: 44025826WO01gripping member for receiving the substrate. The recess includes a first sidewall, a second sidewall, and a base surface. A downward force on the base surface of the recess causes the gripping member to deform such that the first sidewall and the second sidewall are moved inward to grip the substrate disposed in the recess.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only exemplary embodiments of the present disclosure and are therefore not to be considered limiting of its scope, as the present disclosure may admit to other equally effective embodiments.

[0010] Figure 1 is a schematic top view of a chemical mechanical polishing (CMP) system, according to certain embodiments.

[0011] Figure 2A is an isometric view of a contact cleaning unit which may be utilized in the CMP system of Figure 1 , according to certain embodiments.

[0012] Figure 2B is a top view of a brush cleaner in Figure 2A, according to certain embodiments.

[0013] Figure 2C is an isometric view of the brush cleaner of Figure 2B, according to certain embodiments.

[0014] Figure 3A is a cross-sectional view of a roller suitable for use with the brush cleaner of Figures 2A-2C, according to certain embodiments.

[0015] Figure 3B is a front view of a roller suitable for use with the cleaning unit of Figures 2A-2C, according to certain embodiments.

[0016] Figure 3C is a front view of another roller suitable for use with the cleaning unit of Figures 2A-2C, according to certain embodiments.8858733_2 3PATENTAttorney Docket No.: 44025826WO01

[0017] Figure 4A is a detailed cross-sectional view of a gripping member in a free-state, according to certain embodiments.

[0018] Figure 4B is a detailed cross-sectional view of the gripping member of Figure 4A gripping a substrate, according to certain embodiments.

[0019] Figure 5A is a cross-sectional view of an exemplary gripping member suitable for use with the roller of Figure 3A, according to certain embodiments.

[0020] Figure 5B is a cross-sectional view of another exemplary gripping member suitable for use with the roller of Figure 3A, according to certain embodiments.

[0021] Figure 5C is a cross-sectional view of another exemplary gripping member suitable for use with the roller of Figure 3A, according to certain embodiments.

[0022] Figure 6 illustrates a flow diagram of a method for cleaning a substrate, according to certain embodiments.

[0023] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further recitation.DETAILED DESCRIPTION

[0024] Embodiments herein generally relate to chemical mechanical polishing (CMP) systems, and in particular, to cleaning systems used within a CMP system and methods related thereto.

[0025] In one embodiment, a brush cleaning system for cleaning a substrate includes a tank and a first support and a second support coupled to the tank. The system also includes a first cylindrical roller coupled to the first support and a second cylindrical roller coupled to the second support. The first support and the second support are operable to move the first and second cylindrical rollers into contact with the substrate. A drive roller coupled to the tank and operable to rotate the substrate. The drive roller includes a cylindrical hub including a circumferential groove formed in an outer surface of the cylindrical hub and includes a gripping member disposed in the 8858733_2 4PATENTAttorney Docket No.: 44025826WO01groove. The gripping member includes a recess in an outer radial surface of the gripping member for receiving the substrate. The recess includes a first sidewall, a second sidewall, and a base surface. Upon applying a downward force to the base surface of the recess, such as by a substrate, the first sidewall and the second sidewall deform towards the center of the recess to grip the substrate to prevent slippage of the vertically positioned substrate.

[0026] Figure 1 illustrates a schematic top view of a chemical mechanical polishing (CMP) system 100. The CMP system 100 generally includes a factory interface module 102, an input module 104, a polishing module 106, and a cleaning module 108. These four major components are generally disposed within the CMP system 100.

[0027] The factory interface module 102 includes a support to hold a plurality of cassettes 110, a housing 111 that encloses a chamber, and one or more interface robots 112. The interface robot 112 generally provides the range of motion required to transfer substrates between the cassettes 110 and one or more of the other modules of the CMP system 100.

[0028] Unprocessed substrates are generally transferred from the cassettes 110 to the input module 104 by the interface robot 112. The input module 104 generally facilitates transfer of a substrate between the interface robot 112 and a transfer robot 114. The transfer robot 114 transfers the substrate between the input module 104 and the polishing module 106.

[0029] The polishing module 106 generally comprises a transfer station 116, one or more polishing stations 118, and one or more non-contact cleaning units 140. The transfer station 116 is disposed within the polishing module 106 and is configured to accept the substrate from the transfer robot 114. The transfer station 116 transfers the substrate to at least one carrier head 124 of a polishing station 118 that retains the substrate during polishing.

[0030] The polishing stations 118 each includes a rotatable disk-shaped platen on which a polishing pad 120 is situated. The platen is operable to rotate about an axis. The polishing pad 120 can be a two-layer polishing pad with an outer polishing layer 8858733_2 5PATENTAttorney Docket No.: 44025826WO01and a softer backing layer. The polishing stations 118 each further includes a dispensing arm 122, to dispense a polishing liquid, e.g., an abrasive slurry, onto the polishing pad 120. In the abrasive slurry, the abrasive particles can be silicon oxide, but some polishing processes use cerium oxide abrasive particles. Each polishing station 118 can also include a conditioner head 123 to maintain the polishing pad 120 at a consistent surface roughness.

[0031] The polishing stations 118 each includes at least one carrier head 124. The at least one carrier head 124 is operable to hold a substrate against the polishing pad 120 during a polishing operation. Following the polishing operation performed on a substrate, the at least one carrier head 124 transfers the substrate back to the transfer station 116.

[0032] The transfer robot 114 then removes the substrate from the polishing module 106 through an opening connecting the polishing module 106 with the remainder of the CMP system 100. The transfer robot 114 removes the substrate in a horizontal orientation from the polishing module 106 and transfers the substrate to the cleaning module 108.

[0033] The cleaning module 108 generally includes one or more cleaning devices that can operate independently or in concert. For example, the cleaning module 108 can include, from top to bottom in Figure 1, a resist removal module 128, an input module 129, one or more brush or buffing pad module 131 , 132, a megasonic cleaner 133, and a drying module 134. Other possible cleaning devices include chemical spin cleaners and jet spray cleaners (not shown). A transport system, e.g., an overhead conveyor 130 that supports robot arms, can walk or run the substrate from cleaning device to cleaning device. The substrate is then transferred to the megasonic cleaner 133 in which high frequency vibrations produce controlled cavitation in a cleaning liquid to clean the substrate. Alternatively, the megasonic cleaner 133 can be positioned before the brush or buffing pad module 131, 132. A final rinse can be performed in a rinsing module before being transferred to the drying module 134.

[0034] The one or more brush module 131, 132, as described further below regarding Figures 2A-2C, directly contacts the substrate and may be a brush8858733_2 6PATENTAttorney Docket No.: 44025826WO01scrubbing module using a rotating brush to scrub the substrate surface. Briefly, the one or more brush module 131, 132 are devices in which the substrate can be placed and the surfaces of the substrate are contacted with rotating brushes to remove any remaining particulates. In some embodiments, a brush moves back and forth across the substrate, applying cleaning solution during the scrubbing process. The rotating brush uses friction between the brush bristles or nodules formed on a porous brush and the substrate surface, as well as centrifugal force generated by the rotating brush to dislodge particles and contaminants from the substrate surface. The cleaning solution concurrently dissolves and weakens the bonds between particles and the substrate surface. Following dislodgment of contaminants from the substrate surface, the cleaning solution, flowing through the brush bristles, flushes the contaminants from the substrate surface.

[0035] The CMP system 100 includes a controller 160, which generally includes one or more processors, memory, and support circuits. The one or more processors may include a central processing unit (CPU) and may be one of any form of a general purpose processor that can be used in an industrial setting. The memory, or non-transitory computer-readable medium, is accessible by the one or more processors and may be one or more of memory such as random access memory (RAM), read only memory (ROM), floppy disk, hard disk, or any other form of digital storage, local or remote. The support circuits are coupled to the one or more processors and may comprise cache, clock circuits, input / output subsystems, power supplies, and the like. The various methods disclosed herein may generally be implemented under the control of the one or more processors by the one or more processors executing computer instruction code stored in the memory as, for example, a software routine. When the computer instruction code is executed by the one or more processors, the one or more processors controls the CMP system 100 to perform processes in accordance with the various methods disclosed herein.

[0036] Figure 2A is an isometric view of a brush cleaner 200, which may be utilized as one or more brush or buffing pad module 131, 132 in the CMP system 100 as described above. A lid portion of the brush cleaner 200, which includes a door, has been removed from Figures 2A-2C for ease of discussion. Figure 2B is a top view of8858733_2 7PATENTAttorney Docket No.: 44025826WO01the brush cleaner 200 loaded with a substrate 201. Figure 2C is an isometric view of the interior of the brush cleaner 200 showing cylindrical rollers 228 in a processing position, in which the cylindrical rollers 228 are closed (e.g., pressed) against major surfaces of the substrate 201. The brush cleaner 200 shown in Figures 2A-2C can be a scrubber type brush box-type horizontal cleaner. The example brush cleaner 200 includes a tank 205 that is supported by a first support 225 and a second support 230. The first support 225 and the second support 230 are movably coupled to the base 240.

[0037] The brush cleaner 200 includes a plurality of scrubbing devices, such as at least a first and second cylindrical rollers 228, located inside the tank 205. In this example, a first cylindrical roller 228 is mounted to the first support 225, and a second cylindrical roller 228 is mounted to the second support 230. The first and second cylindrical rollers 228 may be coupled to actuators (not shown) for rotating the cylindrical rollers 228 about axes A' and A". The cylindrical rollers 228 are coupled to and controlled by the controller 160, which may control the rotational speed or rotational direction of the rollers 228. In one example, the first roller 228 is rotated in a clockwise direction, and the second roller 228 is rotated in a counterclockwise direction.

[0038] In operation, the first and second supports 225, 230 may be moved simultaneously relative to a base 240. Such movement may cause the first and second cylindrical rollers 228 to close against the substrate 201 as shown in Figure 2C, or to cause the first and second cylindrical rollers 228 to be spaced apart to allow insertion and / or removal of the substrate 201 from the brush cleaner 200. In some embodiments, each cylindrical roller 228 includes a plurality of raised nodules 215 across its outer surface and a plurality of valleys 217 located among the nodules 215.

[0039] The brush cleaner 200 also include a substrate support system 310 adapted to support and rotate a substrate 201. In one embodiment, the substrate support system 310 includes one or more support rollers 350 rotatable by one or more rotation actuators, such as drive motors 351. In some embodiments, only a portion of the support rollers 350 are driven by actuators while others are free to rotate, but are not driven. As shown in Figures 2B and 2C, each support roller 350 is disposed at the 8858733_2 8PATENTAttorney Docket No.: 44025826WO01end of an output shaft 352 of a respective drive motor 351. The support rollers 350 are configured to support the substrate 201 and facilitate rotation of the substrate 201 about an axis that is perpendicular to the horizontal plane (i.e., X-Y plane). In some embodiments, some rotation of some or all of the support rollers 350 causes rotation of the substrate 201. In some embodiments, the rollers 350 are made from a plastic material or other polymeric material.

[0040] Figure 3A is a cross-sectional view of an exemplary embodiment of a support roller 350 suitable for use with the brush cleaner 200. In some embodiments, the support roller 350 is axis-symmetric about a center axis 353. The support roller 350 rotates about the central axis 353 to rotate the substrate 201. The support roller 350 includes a mandrel 354, a flange 355, and a gripping member 470. Together, the mandrel 354 and the flange 355 form a groove 356 formed in an outer radial surface of the support roller 350 and extending around the circumference of the support roller 350 in which the gripping member 470 sits.

[0041] The mandrel 354 includes a mandrel shaft 357, a mandrel flange 358, a mandrel body 359, and a flange interface 360. In some embodiments, the mandrel 354 is monolithic. The mandrel shaft 357 is coupled to the output shaft 352 of a respective drive motor 351. The mandrel shaft 357 is rotationally coupled to the output shaft 352 such that rotation of the respective drive motor 351 is imparted on the support roller 350. The mandrel flange 358 extends radially outward from the mandrel body 359. The mandrel flange 358 has a first surface 361 and a second surface 362 opposite the first surface 361. The first surface 361 of the mandrel flange 358 defines a side of the mandrel 354. The second surface 362 defines an inner wall of the groove 356. The mandrel body 359 includes an outer radial surface 363. The outer radial surface 363 of the mandrel body 359 defines an inner radial surface (e.g., a base surface) of the groove 356. In some embodiments, the outer radial surface 363 of the mandrel body 359 (e.g., the base surface and / or inner radial surface of the groove 356) includes a recessed portion 366. The recessed portion 366 may be disposed around the circumference of the outer radial surface 363 of the mandrel body 359. The flange interface 360 extends axially from the mandrel body 359 and couples to the flange 355. In some embodiments, the flange interface 360 is disposed inside a8858733_2 9PATENTAttorney Docket No.: 44025826WO01bore of the flange 355. The flange 355 includes a first surface 364 and a second surface 365 opposite the first surface 364. The first surface defines a second inner wall of the groove 356. In some embodiments, the mandrel 354 and the flange 355 are able to be disassembled so that the gripping member 470 can be installed and uninstalled from the groove 356. In some embodiments, the mandrel 354 and flange 355 are monolithic.

[0042] The gripping member 470 includes an annular body 471 and is disposed in the groove 356 and is configured to grip a substrate 201 during substrate processing (e.g., during operation of the CMP system 100). In some embodiments, the groove 356 is narrower than the width of the gripping member 470. In some embodiments, the groove 356 is wider than the width of the gripping member 470.

[0043] The gripping member 470 grips the substrate 201 to prevent the substrate 201 from slipping. When the substrate 201 slips, rotation is not transferred from the drive motor 351 to the substrate 201 and the substrate 201 may remain rotationally stagnant relative to a horizontal axis of the brush cleaner 200. If the substrate 201 is rotationally stagnant during substrate processing, the substrate 201 may be non-uniform ly cleaned and / or polished.

[0044] In some embodiments, the gripping member 470, the mandrel 354, and / or the flange 355 may include anti-rotation features preventing the gripping member 470 from slipping around the mandrel 354 causing the substrate 201 to remain rotationally stagnant during substrate processing.

[0045] For example, Figures 3B-3C illustrate exemplary embodiments of antirotation features. Figure 3B illustrates a front view of a roller 350 with the flange 355 removed. In the embodiment illustrated in Figure 3B, the anti-rotation feature includes scalloped portions 367 in the outer radial surface 363 of the mandrel body 359. There may be one or more scalloped portions 367 around the circumference of the outer radial surface 363. The scalloped portions 367 allow the outer radial surface 363 of the mandrel body 359 to act like teeth to dig into the gripping member 470. In some embodiments, as the gripping member 470 deforms (as discussed below), the gripping8858733_2 10PATENTAttorney Docket No.: 44025826WO01member 470 bites into the scalloped portions 367. Thus, the scalloped portions 367 prevent slippage between the gripping member 470 and the mandrel 354.

[0046] Figure 3C illustrates a front view of a roller 350 with the flange 355 removed and another embodiment of the anti-rotation feature. In the embodiment shown in Figure 4B, the anti-rotation feature may be the outer radial surface 363 of the mandrel body 359, itself. In other words, the mandrel body 359 has a non-circular cross-section (e.g., male part) and the gripping member 470 has a mating inner region (e.g., female part) that is similarly sized and similarly configured as the mandrel body 359. When the mandrel body 359 includes a non-circular cross-section, it prevents slippage between the mandrel 354 and the gripping member 470. In some embodiments, the non-circular cross-section may be polygonal. For instance, in some embodiments, the non-circular cross section may be triangular, square, pentagonal, or hexagonal. In some embodiments, the non-circular cross-section may include any number of sides (e.g. flat sides). In some embodiments, the non-circular cross-section may include teeth around the circumference.

[0047] Figures 4A-4B are detailed cross-sectional views of a gripping member 470. Figure 4A is a cross-sectional view of the gripping member 470 in a free-state (e.g., not gripping substrate 201) and Figure 4B is a cross-sectional view of the gripping member 470 gripping the substrate 201.

[0048] The gripping member 470 is made of a deformable material. In some embodiments, the deformable material is an elastomer. In some embodiments, the elastomer is polyurethane or silicone. In some embodiments, the gripping member 470 is made of a material with a durometer of about 55 to about 70 shore A, such as about 60 to about 65 shore A. In some embodiments, the gripping member 470 may be machined or may be injection molded. In some embodiments, the gripping member 470 may be hydrophobic. In some embodiments, the gripping member 470 may be hydrophilic.

[0049] The annular body 471 of the gripping member 470 includes an inner surface 472, a first side surface 473, a second side surface 474, and an outer radial surface 475. The annular body 471 is disposed about the outer radial surface 363 of the8858733_2 11PATENTAttorney Docket No.: 44025826WO01mandrel body 359. In some embodiments, the annular body 471 is dimensioned such that the annular body 471 and the groove 356 are interference fit. In some embodiments, the annular body 471 is dimensioned such that the annular body 471 and the groove 356 have a clearance between them so as to not over-constrain a substrate 201.

[0050] The annular body 471 further includes a groove 476 in the outer surface 475 extending around the circumference of the annular body 471. The groove 476 is configured to selectively grip the substrate 201 (as shown in Figure 4B).

[0051] The groove 476 includes a first portion 477 and a second portion 478. The first portion 477 of the groove 476 is located at the base of the groove 476 (e.g., the inner-most radial part of the groove 476) and the second portion 478 of the groove 476 is located at the top of the groove 476 (e.g., the outer-most radial part of the groove 476).

[0052] The first portion 477 includes a first sidewall 479, a second sidewall 480 opposite the first sidewall 479, and a base 481. The width of the first portion 477 (e.g., the distance between the first sidewall 479 and second sidewall 480) may be larger than the thickness of the substrate 201. In some embodiments, the width of the first portion 477 may be greater than 0.0 millimeters (mm), such as about 2.0 mm, such as about 0.5 mm to about 1.0 mm, such as about 0.8 mm. In some embodiments, the width of the first portion 477 is slightly larger than the thickness of the substrate so that the substrate 201 does not need to be pushed into the first portion 477. In some embodiments, the comers where first sidewall 479 meets the base 481 and where the second sidewall 480 meets the base 481 are radiused. In some embodiments, the height of the first sidewall 479 and the second sidewall are about 0.5 mm to about 1.0 mm.

[0053] The second portion 478 includes a third sidewall 482 and a fourth sidewall 483. The second portion 478 may taper from a larger width at the outer-most radial portion of the second portion 478 down to a narrower width at the inner-most radial portion of the second portion 478. As an example, the third sidewall 482 and the fourth sidewall 483 may be angled inward towards a center of the groove 476. In some8858733_2 12PATENTAttorney Docket No.: 44025826WO01embodiments, the first portion 477 is also tapered. In some embodiments, the taper of the first portion 477 includes a steeper angle than the second portion 478 (e.g., the first sidewall 479 can include a steeper taper angle than the third sidewall 482 and / or the second sidewall 480 can include a steeper taper angle than the fourth sidewall 483). In some embodiments, an angle between the third sidewall 482 and the fourth sidewall 483 may be about 30 degrees to about 135 degrees, such as between about 45 degrees and about 90 degrees, such as about 60 degrees. In some embodiments, the angle between the third sidewall 482 and the fourth sidewall 483 is larger than an angle between the first sidewall 479 and the second sidewall 480.

[0054] According to one mode of operation, when a substrate 201 is disposed in the first portion 477 of the groove 476 (as shown in Figure 4B) and a downward force is applied to the first portion 477 of the groove 476, the gripping member 470 is configured to deform to grip the substrate 201 (as shown in Figure 4B). In some embodiments, the downward force applied to the first portion 477 of the groove 476 due to the rotational contract of the cylindrical rollers 228 causes the gripping member 470 to locally deform to grip the substrate 201. The recessed portion 366 of the base surface 363 of the groove 356 allows the gripping member 470 to locally deform into the recessed portion 366 (as shown in Figure 4B). In some embodiments, the recessed portion 366 is greater than about 0.0 mm, such as up to about 1.0 mm, such as about 0.25 mm to about 0.5 mm, such as about 0.5 mm. The recess portion 366 width is smaller than the gripping member 470 width. When the gripping member 470 locally deforms into the recessed portion 366, the first sidewall 479 of the first portion 477 of the groove 476 and the second sidewall 480 of the first portion 477 of the groove 476 deform towards a center of the groove 476, which reduces the width of the first portion and causes the sidewalls to squeeze (e.g., pinch) the substrate 201. While the downward force is applied, the gripping member 470 continues to squeeze and grip the substrate 201. In some embodiments, the downward force is applied by installing the substrate 201 into the groove 476. In some embodiments, the downward force is caused by and maintained by forces exerted on the substrate 201 during operation. In some embodiments, the downward force is maintained by the forces exerted by the cylindrical rollers 228 on the substrate 201.8858733_2 13PATENTAttorney Docket No.: 44025826WO01

[0055] The increased contact area between the substrate 201 and the gripping member 470, due to the local deformation, increases the friction forces between the gripping member 470 and the substrate 201. Thus, the support roller 350 is able to transfer rotation and torque to the substrate 201 from the respective drive motor 351. Further, the increased contact area allows for a larger torque or speed mismatch between the support roller 350 and the cylindrical rollers 228.

[0056] Figures 5A-5C are cross-sectional views exemplary embodiments of the gripping member 470. The embodiments illustrated in Figures 5A-5C are similar but vary in geometry of the first portion 477 of the groove 476.

[0057] In the embodiment shown in Figure 5A, the first portion 477 of the groove 476 is substantially rectangular. In some embodiments, the first sidewall 479 and the second sidewall 480 are vertical (e.g., perpendicular to the central axis of the roller 350). In some embodiments, the first sidewall 479 and the second sidewall 480 are parallel to one another. In some embodiments, the first sidewall 479 and the second sidewall 480 are perpendicular to the base 481 of the groove 476.

[0058] In the embodiment shown in Figure 5B, the first portion 477 of the groove 476 is tapered such that the first sidewall 479 and the second sidewall 480 are wider at their outer-most radial point than they are at their inner-most radial point. In some embodiments, the angle between the first sidewall 479 and the second sidewall 480 is less than the angle between the third sidewall 482 and the fourth sidewall 483 of the second portion 478 of the groove 476. In some embodiments, the angle between the first sidewall 479 and the second sidewall 480 is at least about 0 degrees, such as up to about 135 degrees, such as about 15 degrees to about 90 degrees, such as between about 35 degrees and 55 degrees, such as about 45 degrees. In some embodiments, the angle between the first sidewall 479 and the second sidewall 480 matches the chamfer angle of the substrate 201 to be disposed in the groove 476. In the embodiment shown in Figure 5B, the narrowest portion of the first portion 477 of the groove 476 is narrower than the substrate 201. As a non-limiting example, the narrowest portion may be about 0.0 mm to about 1.0 mm such as about 0.25 mm to about 0.75 mm, such as about 0.45 mm. In such embodiments, gripping member 470 may deform when a portion (e.g., an edge or a chamfer) of the substrate 201 exerts a 8858733_2 14PATENTAttorney Docket No.: 44025826WO01downward force on the first sidewall 479 or the second sidewall 480 rather than on the base surface 481 of the groove 476 as previously described.

[0059] In the embodiment shown in Figure 5C, the first sidewall 479 is tapered and the second sidewall 480 is vertical (e.g., perpendicular to the central axis of the roller 350). In some embodiments, the first sidewall 479 tapers toward the center of the groove 476 and the second sidewall 480 is perpendicular to the base 481 of the groove 476. In some embodiments, the taper angle of the first sidewall 479 is narrower than the taper angle of the fourth sidewall 483. As a non-limiting example, the taper angle of the fourth sidewall 483 may be about 15 degrees from the vertical to about 67.5 degrees from the vertical, whereas the taper angle of the first sidewall 479 may be about 0 degrees from the vertical to about 15 degrees from the vertical. In some embodiments, the narrowest portion of the first portion 477 of the groove 476 is narrower than the substrate 201. As a non-limiting example, the narrowest portion of the first portion 477 may be about 0.0 mm to about 1.0mm, such as about 0.25 mm to about 0.75 mm, such as about 0.45 mm. In such embodiments, gripping member 470 may deform when a portion (e.g., an edge or a chamfer) of the substrate 201 exerts a downward force on the first sidewall 479 or the second sidewall 480 rather than on the base surface 481 of the groove 476 as previously described.

[0060] Referring back to Figures 2A-2C, the pair of cylindrical rollers 228 are supported by a pivotal mounting adapted to move the cylindrical rollers 228 into and out of contact with the substrate 201, such as a semiconductor wafer. During processing in the brush cleaner 200, the cylindrical rollers 228 are brought into contact with the substrate 201 while the cylindrical rollers 228 are rotated by the actuators (not shown). At the same time, the substrate 201 is gripped and rotated in the R direction by rotating the support rollers 350, as shown in Figure 2C. A cleaning fluid, such as deionized water and / or acid or base containing aqueous solution, is applied to the surface of the substrate 201 from a fluid source while the substrate 201 and cylindrical rollers 228 are rotated by the various actuators and motors.

[0061] The brush cleaner 200 may further comprise a plurality of sprayers 221 coupled to a source 223 of cleaning fluid via a supply pipe 226. The sprayers 221 are configured to dispense a high-pressure liquid spray onto the substrate surfaces, aiding 8858733_2 15PATENTAttorney Docket No.: 44025826WO01in the removal of particles, contaminants, and residues. The sprayers 221 can incorporate various configurations, such as a fluid jet, spray bar with nozzles, showerstyle spray manifold, or cryogenic aerosol jet.

[0062] In various embodiments of the present disclosure, the cleaning fluid utilized in the brush cleaner may include, but is not limited to deionized (DI) water, diluted citric acid, diluted Quaternary ammonium compound (a mixture of organic solvents, such as glycol ether, tetramethyl ammonium hydroxide, and other additives), diluted ammonium hydroxide (NH4OH), diluted hydrogen peroxide (H2O2), NH4OH and H2O2 mixture (SC1), diluted hydrofluoric acid, sulfuric acid (H2SO4) and hydrogen peroxide (H2O2) mixture, Electra clean, or any other liquid solution used for substrate cleaning.

[0063] In some embodiments, the sprayers 221 may be positioned to spray a cleaning fluid at the surfaces of the substrate 201 or at the one or more cylindrical rollers 228 during a scrubbing process. In some embodiments, substrate cleaning fluid and / or brush cleaning fluid may be supplied from an internal region of the cylindrical rollers 228. Fluids provided to the interior of the cylindrical rollers 228 may clean the surface of the substrate 201 or remove debris found on the surface of the rollers 228.

[0064] Figure 6 illustrates a flow diagram of a method 600 for cleaning a substrate (e.g., substrate 201) which may be performed by a controller of a CMP system (e.g., controller 160 of CMP system 100).

[0065] At operation 602, a substrate 201 is placed in a brush or buffing pad module 131, 132. For example, the brush or buffing pad module 131, 132 may be a brush cleaner 200. The substrate 201 is positioned vertically on the one or more support rollers 350 of the brush cleaner 200. In some embodiments, the substrate 201 is transferred to the brush cleaner 200 after being polished in a polishing station of the polishing stations 118.

[0066] The substrate 201 is disposed in the groove 476 of the gripping member 470 disposed about the cylindrical hub of one or more of the support rollers 350. The substrate 201 is installed into the first portion 477 of the groove 476 (e.g., the innermost radial portion of the groove 476). In some embodiments, the downward force 8858733_2 16PATENTAttorney Docket No.: 44025826WO01applied to a portion of the first portion 477 of the groove while installing the substrate 201 into the groove 476 causes the gripping member 470 to locally deform and causes at least a portion of the groove 476 (e.g., the first sidewall 479, the second sidewall 480, the third sidewall 482, and / or the fourth sidewall 483) to squeeze (e.g., pinch) the substrate thus gripping the substrate. In some embodiments, installing the substrate 201 does not cause the gripping member 470 to grip the substrate, rather, the gripping member 470 is in a free state (as shown in Figure 4A) and operating forces, which can be applied by the cylindrical rollers 228, in a downward direction cause the gripping member 470 to grip the substrate 201. In this respect, the substrate 201 is advantageously retained by the roller 350 to prevent substrate slippage as the substrate 201 is rotated by one or more of the rollers 350 during processing.

[0067] At operation 604, the brush cleaner 200 cleans the substrate 201. In one example, the cylindrical rollers 228 are pressed against the major surfaces of the substrate 201. In some embodiments, at least one of the rollers 350 are rotated by a rotation actuator to cause rotation of the substrate 201. The one or more rollers 350 apply sufficient pressure to the surface of the substrate 201 to grip the substrate 201 while allowing the substrate 201 to rotate about its central axis (e.g., axis normal to the major surfaces of the substrate 201). The cylindrical rollers 228 contacting the substrate 201 are also rotated during cleaning of the substrate 201. A cleaning fluid is applied to the surface of the substrate 201 as the cylindrical rollers 228 are rotated.

[0068] At operation 606, after cleaning, the substrate 201 is removed from the brush or buffing pad module 131, 132 (e.g., the brush cleaner 200). In one example, the substrate 201 is released when a downward force is no longer applied to groove 476 of the gripping member 470. When the downward force is no longer applied, the gripping member 470 is returned to the free-state (as shown in Figure 4A) and the substrate 201 is released.

[0069] In some embodiments, after cleaning, the substrate 201 is transferred to a polishing station of the polishing stations 118 for polishing or additional polishing if the substrate 201 was previously polished.8858733_2 17PATENTAttorney Docket No.: 44025826WO01

[0070] In some embodiments, after polishing, the substrate 201 is transferred to a non-contact cleaning unit, such as a megasonic cleaner 133 and / or a drying module 134. The non-contact cleaning unit then cleans the substrate 201 using a non-contact cleaning method, such as megasonic cleaning or spray cleaning. For example, the substrate 201 may undergo spray cleaning where high-pressure jets of cleaning solution are directed toward the substrate 201 to dislodge particles and contaminants. It is contemplated that the substrate 201 may be transferred to a second brush or buffing pad module 131, 132 instead of or in addition to the non-contact cleaning unit. In some embodiments, after cleaning, the substrate is transferred to the factory interface module 102 and cassettes 110.

[0071] When introducing elements of the present disclosure or exemplary aspects or embodiments thereof, the articles “a,” “an,” “the” and “said” are intended to mean that there are one or more of the elements.

[0072] The terms “comprising,” “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.

[0073] The term “coupled” is used herein to refer to the direct or indirect coupling between two objects. For example, if object A physically touches object B and object B touches object C, the objects A and C may still be considered coupled to one another — even if objects A and C do not directly physically touch each other. For instance, a first object may be coupled to a second object even though the first object is never directly in physical contact with the second object.

[0074] While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.8858733_2 18

Claims

PATENTAttorney Docket No.: 44025826WO01What is claimed is:

1. A gripping member for use on a rotating substrate support in a substrate processing system, comprising:an annular body including an outer radial surface and an inner radial surface; anda groove disposed in the outer radial surface, the groove including a first sidewall, a second sidewall, and a base surface, wherein a downward force on a portion of the groove causes the annular body to deform such that the first sidewall and the second sidewall are moved inward towards a center of the groove.

2. The gripping member of claim 1 , wherein:the first sidewall includes a first portion and a second portion, the first portion of the first sidewall and the second portion of the first sidewall including different taper angles; andthe second sidewall includes a first portion and a second portion, the first portion of the second sidewall and the second portion of the second sidewall including different taper angles.

3. The gripping member of claim 2, wherein the second portion of the first sidewall includes a steeper taper angle than the first portion of the first sidewall, and wherein the second portion of the second sidewall includes a steeper taper angle than the first portion of the second sidewall.

4. The gripping member of claim 2, wherein the second portion of the first sidewall includes a taper angle perpendicular to a central axis of the annular body.

5. The gripping member of claim 4, wherein the second portion of the second sidewall includes a taper angle perpendicular to the central axis of the annular body.

6. The gripping member of claim 1, wherein the annular body comprises an elastomer.8858733_2 19PATENTAttorney Docket No.: 44025826WO017. The gripping member of claim 1 , wherein the annular body includes a material having a durometer of about 60 to 65 Shore A.

8. A rotating substrate support for using in a substrate processing system, comprising:a cylindrical hub including a circumferential groove formed in an outer surface radial surface of the cylindrical hub; anda gripping member disposed in the circumferential groove, the gripping member including a recess disposed in an outer radial surface of the gripping member for receiving a substrate, the recess including a first sidewall, a second sidewall, and a base surface, wherein a downward force on a portion of the recess causes the gripping member to deform such that the first sidewall and the second sidewall are moved inward to grip the substrate disposed in the recess.

9. The rotating substrate support of claim 8, wherein the circumferential groove includes a first groove portion and a second groove portion, the first groove portion being radially outward from the second groove portion, the first groove portion being wider than a width of the gripping member, and the second groove portion being narrower than the width of the gripping member.

10. The rotating substrate support of claim 8, wherein the cylindrical hub comprises:a mandrel; anda flange coupled to the mandrel, wherein a surface of the flange, a radial surface of the mandrel, and an axial surface of the mandrel form the circumferential groove.

11. The rotating substrate support of claim 8, wherein the circumferential groove includes at least one anti-rotation feature, the anti-rotation feature engaged with the gripping member and configured to prevent the gripping member from rotating about the cylindrical hub.

12. The rotating substrate support of claim 8, wherein:8858733_2 20PATENTAttorney Docket No.: 44025826WO01the first sidewall includes a first portion and a second portion, the first portion of the first sidewall and the second portion of the first sidewall including different taper angles; andthe second sidewall includes a first portion and a second portion, the first portion of the second sidewall and the second portion of the second sidewall including different taper angles.

13. The rotating substrate support of claim 12, wherein the second portion of the first sidewall includes a steeper taper angle than the first portion of the first sidewall, and wherein the second portion of the second sidewall includes a steeper taper angle than the first portion of the second sidewall.

14. The rotating substrate support of claim 12, wherein the second portion of the first sidewall includes a taper angle perpendicular to a central axis of the gripping member.

15. The rotating substrate support of claim 14, wherein the second portion of the second sidewall includes a taper angle perpendicular to the central axis of the gripping member.

16. The rotating substrate support of claim 8, wherein the gripping member comprises an elastomer.

17. The rotating substrate support of claim 8, wherein the gripping member includes a material having a durometer of about 60 to 65 Shore A.

18. A brush cleaning system for cleaning a substrate, comprising:a tank;a first support and a second support coupled to the tank;a first cylindrical roller coupled to the first support;a second cylindrical roller coupled to the second support, wherein the first support and the second support are operable to move the first and second cylindrical rollers into contact with the substrate; and8858733_2 21PATENTAttorney Docket No.: 44025826WO01a drive roller coupled to the tank and operable to rotate the substrate, the drive roller including:a cylindrical hub including a circumferential groove formed in an outer surface radial surface of the hub; anda gripping member disposed in the circumferential groove, the gripping member including a recess disposed in an outer radial surface of the gripping member for receiving the substrate, the recess including a first sidewall, a second sidewall, and a base surface, wherein a downward force on the base surface of the recess causes the gripping member to deform such that the first sidewall and the second sidewall are moved inward to grip the substrate disposed in the recess.

19. The brush cleaning system of claim 18, wherein:the first sidewall includes a first portion and a second portion, the first portion of the first sidewall and the second portion of the first sidewall including different taper angles; andthe second sidewall includes a first portion and a second portion, the first portion of the second sidewall and the second portion of the second sidewall including different taper angles.

20. The brush cleaning system of claim 19, wherein the second portion of the first sidewall includes a steeper taper angle than the first portion of the first sidewall, and wherein the second portion of the second sidewall includes a steeper taper angle than the first portion of the second sidewall.8858733_2 22

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