POLISHING APPARATUS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on and claims priority from Japanese Patent Application No. 2024-231813, filed on December 27, 2024, with the Japan Patent Office, the disclosure of which is incorporated herein in its entirety by reference.

TECHNICAL FIELD

[0002] The present disclosure relates to a polishing apparatus.

BACKGROUND

[0003] The chemical mechanical polishing (CMP) apparatus may include a buffing device so as to clean a substrate after polishing. The buffing device presses a buff pad against a substrate after polishing and causes relative motion therebetween. Accordingly, the buffing device slightly polishes the substrate or removes deposits that have adhered to the substrate, thereby cleaning the substrate. Thus, since the buffing device is capable of polishing the substrate, it may broadly be included in a polishing apparatus.

[0004]Meanwhile, an example of such a buffing device is disclosed in Japanese Patent No. 7145283. As illustrated in FIGS. 8 and 9A of Japanese Patent No. 7145283, the buffing device includes an outer cover 550a attached to a stationary portion of a buff head, and an inner cover 550b attached to a rotary portion of the buff head. The inner cover 550b has a cylindrical shape and is attached to the rotary portion so as to extend upward from the rotary portion of the buff head. In the meantime, the outer cover 550a has a cylindrical shape and is attached to the stationary portion so as to extend downward from the stationary portion of the buff head. In addition, the outer cover 550a surrounds the inner cover 550b. Thus, in the buffing device disclosed in Japanese Patent No. 7145283, while rotation of the rotary portion of the buff head relative to the stationary portion is allowed, penetration of liquid into the interior of the outer cover 550a and the inner cover 550b is prevented. See, for example, Japanese Patent No. 6348028.

SUMMARY

[0005] A polishing apparatus according to the present disclosure is a polishing apparatus that includes: a stationary member; a shaft that penetrates the stationary member, extends in a vertical direction, and rotates about a central axis; a rotary member that rotates integrally with the shaft; a first lower cover member attached to the rotary member, extending upward from the rotary member to an upper end thereof, and having a cylindrical shape, the first lower cover member being disposed to surround the central axis; an upper cover member attached to the stationary member, extending downward from the stationary member to a lower end thereof, and having a cylindrical shape, the upper cover member being disposed to surround the central axis and the first lower cover member; and a second lower cover member attached to the first lower cover member, extending upward from the first lower cover member to an upper end thereof while branching from the first lower cover member, and having a cylindrical shape, the second lower cover member being disposed to surround the central axis, the first lower cover member, and the upper cover member.

[0006] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007]FIG. 1 is a plan view illustrating an overall configuration of a processing apparatus according to an embodiment of the present disclosure.

[0008]FIG. 2 is a perspective view schematically illustrating a first polishing apparatus illustrated in FIG. 1.

[0009]FIG. 3A is a plan view illustrating a cleaning module illustrated in FIG. 1.

[0010]FIG. 3B is a side view illustrating the cleaning module illustrated in FIG. 1.

[0011]FIG. 4 is a schematic view illustrating a general configuration of a buffing device illustrated in FIG. 1.

[0012]FIG. 5 is a view illustrating processing processes on a buff table and a dressing table illustrated in FIG. 4.

[0013]FIG. 6A is a view illustrating operations of the buff table, the dressing table, and a buff head illustrated in FIG. 5.

[0014]FIG. 6B is a view illustrating operations of the buff table, the dressing table, and the buff head illustrated in FIG. 5.

[0015]FIG. 6C is a view illustrating operations of the buff table, the dressing table, and the buff head illustrated in FIG. 5.

[0016]FIG. 6D is a view illustrating operations of the buff table, the dressing table, and the buff head illustrated in FIG. 5.

[0017]FIG. 7 is a perspective view illustrating a buffing component illustrated in FIG. 5.

[0018]FIG. 8 is a cross-sectional view of the buff head illustrated in FIG. 5.

[0019]FIG. 9 is a cross-sectional plan view of the buff head illustrated in FIG. 5.

[0020]FIG. 10 is an enlarged view of portion A in FIG. 8.

[0021]FIG. 11 is an enlarged view of portion A in FIG. 8 when a cleaning liquid is supplied from a pad rinsing nozzle to the buff head.

[0022]FIG. 12 is an enlarged view of portion B in FIG. 9.

[0023]FIG. 13 is a view illustrating a flow of liquid at a connection portion of a cover member.

[0024]FIG. 14 is an enlarged perspective view of the buff head, in which rear surfaces of a first member and a second member are illustrated by dashed lines.

[0025]FIG. 15 is a cross-sectional view of the buff head when the buff head is positioned above a dresser.

[0026]FIG. 16 is a cross-sectional view of the buff head illustrated in FIG. 5 during the swing of the buff head.

DETAILED DESCRIPTION

[0027] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made without departing from the spirit or scope of the subject matter presented here.

[0028] In the buffing device disclosed in Japanese Patent No. 7145283, penetration of liquid into the interior of the outer cover 550a and the inner cover 550b is prevented. However, when liquid is supplied from an obliquely downward direction of the buff head, the liquid may flow along an outer surface of the inner cover 550b and infiltrate into the interior of the covers through a gap between the inner cover 550b and the outer cover 550a.

[0029] Accordingly, the present disclosure provides a buffing device (polishing apparatus) that makes it difficult for liquid to penetrate the interior.

[0030] A polishing apparatus according to the present disclosure is a polishing apparatus that includes: a stationary member; a shaft that penetrates the stationary member, extends in a vertical direction, and rotates about a central axis; a rotary member that rotates integrally with the shaft; a first lower cover member attached to the rotary member, extending upward from the rotary member to an upper end thereof, and having a cylindrical shape, the first lower cover member being disposed to surround the central axis; an upper cover member attached to the stationary member, extending downward from the stationary member to a lower end thereof, and having a cylindrical shape, the upper cover member being disposed to surround the central axis and the first lower cover member; and a second lower cover member attached to the first lower cover member, extending upward from the first lower cover member to an upper end thereof while branching from the first lower cover member, and having a cylindrical shape, the second lower cover member being disposed to surround the central axis, the first lower cover member, and the upper cover member.

[0031] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings described below, identical or corresponding components are denoted by the same reference numerals, and duplicate descriptions thereof will be omitted.

Processing Apparatus 1000

[0032]FIG. 1 is a plan view illustrating an overall configuration of a processing apparatus 1000 according to an embodiment of the present disclosure. The processing apparatus 1000 is, as an example, a CMP apparatus that performs a processing on a substrate such as a wafer. As illustrated in FIG. 1, the processing apparatus 1000 includes a substantially rectangular housing 1. An interior of the housing 1 is partitioned by partition walls 1a and 1b into a load/unload module 2, a polishing module 3, and a cleaning module 4. The load/unload module 2, the polishing module 3, and the cleaning module 4 are each independently assembled and independently exhausted. The cleaning module 4 includes a power supply unit that supplies power to the processing apparatus 1000, and a controller 5 that controls the processing operation.

Load/Unload Module 2

[0033]The load/unload module 2 includes two or more (four in this embodiment) front load units 20 on which wafer cassettes, each storing a plurality of substrates W, are placed. These front load units 20 are arranged adjacent to the housing 1 and aligned in a width direction (a direction perpendicular to the longitudinal direction) of the processing apparatus 1000. An open cassette, a standard manufacturing interface (SMIF) pod, or a front opening unified pod (FOUP) is mounted on each front load unit 20. The SMIF and FOUP are sealed containers capable of accommodating a wafer cassette therein.

[0034] A traveling mechanism 21 is also installed along the arrangement of the front load units 20 in the load/unload module 2. Two transfer robots 22 (loaders or transfer mechanisms) that are movable along the arrangement direction of the wafer cassettes are mounted on the traveling mechanism 21. Each transfer robot 22 transfers a substrate W by moving along the traveling mechanism 21.

Polishing Module 3

[0035] In the polishing module 3, polishing (planarization) of a substrate W is performed. The polishing module 3 includes a first polishing apparatus 3A, a second polishing apparatus 3B, a third polishing apparatus 3C, and a fourth polishing apparatus 3D. The first polishing apparatus 3A, the second polishing apparatus 3B, the third polishing apparatus 3C, and the fourth polishing apparatus 3D are arranged along a longitudinal direction of the processing apparatus 1000.

[0036]The first polishing apparatus 3A includes a polishing table 30A, a top ring 31A, a polishing liquid supply nozzle 32A, a dresser 33A, and an atomizer 34A. The polishing table 30A is configured to attach thereto a polishing pad (polishing tool) 10 having a polishing surface. The top ring 31A may polish a substrate W by holding and pressing the substrate W against the polishing pad 10 on the polishing table 30A. The polishing liquid supply nozzle 32A is configured to supply a polishing liquid or a dressing liquid (e.g., pure water) to the polishing pad 10. The dresser 33A is used to dress the polishing surface of the polishing pad 10. The atomizer 34A may remove, for example, slurry, polishing by-products, and residues of the polishing pad resulting from dressing on the polishing surface by supplying a mixed fluid of a liquid (e.g., pure water) and a gas (e.g., nitrogen gas) or a liquid (e.g., pure water).

[0037] The second polishing apparatus 3B includes a polishing table 30B, a top ring 31B, a polishing liquid supply nozzle 32B, a dresser 33B, and an atomizer 34B. The third polishing apparatus 3C includes a polishing table 30C, a top ring 31C, a polishing liquid supply nozzle 32C, a dresser 33C, and an atomizer 34C. The fourth polishing apparatus 3D includes a polishing table 30D, a top ring 31D, a polishing liquid supply nozzle 32D, a dresser 33D, and an atomizer 34D.

[0038] The first polishing apparatus 3A, the second polishing apparatus 3B, the third polishing apparatus 3C, and the fourth polishing apparatus 3D have the same configuration. Accordingly, the first polishing apparatus 3A will be described below, and descriptions of the second polishing apparatus 3B, the third polishing apparatus 3C, and the fourth polishing apparatus 3D will be omitted.

[0039]FIG. 2 is a perspective view schematically illustrating the first polishing apparatus 3A. The top ring 31A is supported by a top ring shaft 36. A polishing pad 10 is attached to an upper surface of the polishing table 30A. An upper surface of the polishing pad 10 forms a polishing surface for polishing a substrate W. In another embodiment of the present disclosure, fixed abrasive grains may be used instead of the polishing pad 10. The top ring 31A and the polishing table 30A are configured to be rotatable about their respective central axes as indicated by arrows. The substrate W is held on a lower surface of the top ring 31A by vacuum suction. During polishing, while a polishing liquid is supplied from the polishing liquid supply nozzle 32A to the polishing surface of the polishing pad 10, the substrate W, which is a polishing target, is pressed against the polishing surface of the polishing pad 10 by the top ring 31A and polished. As described above, the first polishing apparatus 3A, the second polishing apparatus 3B, the third polishing apparatus 3C, and the fourth polishing apparatus 3D may polish the substrate W. Accordingly, the first polishing apparatus 3A, the second polishing apparatus 3B, the third polishing apparatus 3C, and the fourth polishing apparatus 3D are included in the polishing apparatus. In the present disclosure, the term "polishing apparatus" refers to an apparatus capable of polishing a polishing target.

First Linear Transporter 6 and Second Linear Transporter 7

[0040] Referring again to FIG. 1, the processing apparatus 1000 includes a first linear transporter 6 and a second linear transporter 7. The first linear transporter 6 is disposed adjacent to the first polishing apparatus 3A and the second polishing apparatus 3B. The first linear transporter 6 has a function of transferring a substrate W among four transfer positions arranged along a direction in which the polishing apparatuses 3A and 3B are aligned (the four transfer positions being referred to as a first transfer position TP1, a second transfer position TP2, a third transfer position TP3, and a fourth transfer position TP4 in order from the load/unload module 2 side).

[0041] The second linear transporter 7 is disposed adjacent to the third polishing apparatus 3C and the fourth polishing apparatus 3D. The second linear transporter 7 has a function of transferring the substrate W among three transfer positions arranged along a direction in which the polishing apparatuses 3C and 3D are aligned (the three transfer positions being referred to as a fifth transfer position TP5, a sixth transfer position TP6, and a seventh transfer position TP7, in order from the load/unload module 2 side).

[0042]The top ring 31A of the first polishing apparatus 3A may move between a polishing position and the second transfer position TP2 by a swinging operation of the top ring 31A. Accordingly, the first polishing apparatus 3A may receive a substrate W placed at the second transfer position TP2. Similarly, the top ring 31B of the second polishing apparatus 3B may move between a polishing position and the third transfer position TP3. Accordingly, the second polishing apparatus 3B may receive a substrate W placed at the third transfer position TP3. The top ring 31C of the third polishing apparatus 3C may move between a polishing position and the sixth transfer position TP6. Accordingly, the third polishing apparatus 3C may receive a substrate W placed at the sixth transfer position TP6. The top ring 31D of the fourth polishing apparatus 3D may move between a polishing position and the seventh transfer position TP7. Accordingly, the fourth polishing apparatus 3D may receive a substrate W placed at the seventh transfer position TP7.

[0043] At the first transfer position TP1, a lifter 11 is disposed to receive a substrate W from the transfer robot 22. The substrate W is delivered from the transfer robot 22 to the first linear transporter 6 via the lifter 11. In addition, a swing transporter 12 is disposed among the first linear transporter 6, the second linear transporter 7, and the cleaning module 4. The substrate W is delivered from the first linear transporter 6 to the second linear transporter 7 by the swing transporter 12. In addition, the substrate W polished in the polishing module 3 is transferred to the cleaning module 4 via the swing transporter 12. A temporary placement table 180 for the substrate W is disposed beside the swing transporter 12.

Cleaning Module 4

[0044]FIG. 3A is a plan view illustrating the cleaning module 4, and FIG. 3B is a side view illustrating the cleaning module 4. As illustrated in FIGS. 3A and 3B, the cleaning module 4 is partitioned into a roll cleaning chamber 190, a first transfer chamber 191, a pen cleaning chamber 192, a second transfer chamber 193, a drying chamber 194, a buffing chamber 300, and a third transfer chamber 195.

[0045] In the roll cleaning chamber 190, an upper roll cleaning device 201A and a lower roll cleaning device 201B are arranged along a vertical direction (see, e.g., FIG. 3B). The upper roll cleaning device 201A and the lower roll cleaning device 201B clean a substrate W by pressing two rotating roll sponges respectively against the front and rear surfaces of the substrate W while supplying a cleaning liquid to the front and rear surfaces of the substrate W. A temporary placement table 204 for the substrate W is provided between the upper roll cleaning device 201A and the lower roll cleaning device 201B.

[0046] In the pen cleaning chamber 192, an upper pen cleaning device 202A and a lower pen cleaning device 202B are arranged along a vertical direction. The upper pen cleaning device 202A is positioned above the lower pen cleaning device 202B (see, e.g., FIG. 3B). The upper pen cleaning device 202A and the lower pen cleaning device 202B clean a substrate W by pressing a rotating pencil sponge against the surface of the substrate W and swinging in a radial direction of the substrate W while supplying a cleaning liquid to the surface of the substrate W. A temporary placement table 203 for the substrate W is provided between the upper pen cleaning device 202A and the lower pen cleaning device 202B.

[0047] In the drying chamber 194, an upper drying device 205A and a lower drying device 205B are arranged along a vertical direction. The filter fan modules 207A and 207B are provided above the upper and lower drying devices 205A and 205B to supply clean air to the upper drying device 205A and the lower drying device 205B, respectively.

[0048] A first transfer robot 209 capable of moving up and down is disposed in the first transfer chamber 191. A second transfer robot 210 capable of moving up and down is disposed in the second transfer chamber 193. A third transfer robot 213 capable of moving up and down is disposed in the third transfer chamber 195. The first transfer robot 209, the second transfer robot 210, and the third transfer robot 213 are respectively movably supported by vertically extending support shafts 211, 212, and 214.

[0049] The first transfer robot 209 is configured to transfer a substrate W among the temporary placement table 180, the upper roll cleaning device 201A, the lower roll cleaning device 201B, the temporary placement table 204, the temporary placement table 203, the upper pen cleaning device 202A, and the lower pen cleaning device 202B. The second transfer robot 210 is configured to transfer a substrate W among the upper pen cleaning device 202A, the lower pen cleaning device 202B, the temporary placement table 203, the upper drying device 205A, and the lower drying device 205B. The transfer robot 22 is configured to take out a substrate W from the upper drying device 205A or the lower drying device 205B and return the substrate W to a wafer cassette (see, e.g., FIG. 1).

[0050] In the buffing chamber 300, a buffing device 300A and a buffing device 300B are provided. The third transfer robot 213 is configured to transfer the substrate W among the upper roll cleaning device 201A, the lower roll cleaning device 201B, the temporary placement table 204, the buffing device 300A, and the buffing device 300B.

Buffing Device 300A and Buffing Device 300B

[0051] Next, the buffing device 300A will be described in more detail. The buffing devices 300A and 300B have similar configurations. Therefore, the following description will focus on the buffing device 300A, and the explanation of the buffing device 300B will be omitted.

[0052]FIG. 4 is a schematic view illustrating a general configuration of the buffing device 300A. As illustrated in FIG. 4, the buffing device 300A includes a buff table 400 that places thereon a substrate W, a buffing component 350, a liquid supply system 700 that supplies a buffing liquid, and a conditioning unit 800. The buffing component 350 includes a buff head 500 to which a buff pad 502 for performing buff cleaning on a processing surface of a substrate W is attached, and a buff arm 600 that holds the buff head 500. The buffing liquid includes at least one of pure water (DIW), a cleaning chemical liquid, and a polishing liquid such as slurry. The buff pad 502 may be formed of, for example, a foamed polyurethane hard pad, a suede-type soft pad, or a sponge.

[0053]The buff table 400 is configured to hold a substrate W by suction. The buff table 400 is also configured to be rotatable about a rotation axis A by a drive mechanism (not illustrated). The buff pad 502 is attached to a surface of the buff head 500 that faces the substrate W. The buff head 500 is configured to be rotatable about a rotation axis B by a drive mechanism (not illustrated). The buff head 500 is also configured to press the buff pad 502 against the processing surface of the substrate W. The buff arm 600 may move the buff head 500 in a direction indicated by arrow C. The buff arm 600 is also configured to swing the buff head 500 to a position where the buff pad 502 faces the conditioning unit 800.

[0054]The conditioning unit 800 performs surface dressing (dressing) on the buff pad 502. The conditioning unit 800 includes a dressing table 810 and a dresser 820 provided on the dressing table 810. The dressing table 810 is configured to be rotatable about a rotation axis D. The dresser 820 may be a diamond dresser having diamond abrasive grains disposed on all or part of a contact surface with the buff pad, a brush dresser having resin-made brush bristles disposed on all or part of a contact surface with the buff pad, or a combination thereof.

[0055] When the buffing device 300A performs dressing of the buff pad 502, the buff arm 600 is pivoted until the buff pad 502 reaches a position facing the dresser 820. The buffing device 300A performs dressing of the buff pad 502 by rotating the dressing table 810 about the rotation axis D while rotating the buff head 500 and pressing the buff pad 502 against the dresser 820.

[0056]The liquid supply system 700 includes a pure water nozzle 710 that supplies pure water (DIW) to a processing surface of the substrate W. The pure water nozzle 710 is connected to a pure water supply source 714 via a pure water pipe 712. An opening/closing valve 716 capable of opening and closing the pure water pipe 712 is provided in the pure water pipe 712. The controller 5 controls opening and closing of the opening/closing valve 716 so as to allow pure water to be supplied to the processing surface of the substrate W at an arbitrary timing.

[0057] The liquid supply system 700 further includes a chemical nozzle 720 that supplies a chemical liquid (Chemi) to the processing surface of the substrate W. The chemical nozzle 720 is connected to a chemical liquid supply source 724 via a chemical liquid pipe 722. An opening/closing valve 726 capable of opening and closing the chemical liquid pipe 722 is provided in the chemical liquid pipe 722. The controller 5 controls opening and closing of the opening/closing valve 726 to allow the chemical liquid to be supplied to the processing surface of the substrate W at an arbitrary timing.

[0058] The buffing device 300A may discharge a buffing liquid from a processing liquid outlet 503 (see, e.g., FIG. 6C) through the buff arm 600, the buff head 500, and the buff pad 502. In other words, the buffing device 300A is configured to selectively supply pure water, a chemical liquid, or slurry to the processing surface of the substrate W. More specifically, a branch pure water pipe 712a branches off between the pure water supply source 714 and the opening/closing valve 716 in the pure water pipe 712. A branch chemical liquid pipe 722a branches off between the chemical liquid supply source 724 and the opening/closing valve 726 in the chemical liquid pipe 722. The branch pure water pipe 712a, the branch chemical liquid pipe 722a, and a slurry pipe 732 connected to a slurry supply source 734 join together at a liquid supply pipe 740. An opening/closing valve 718 capable of opening and closing the branch pure water pipe 712a is provided in the branch pure water pipe 712a. An opening/closing valve 728 capable of opening and closing the branch chemical liquid pipe 722a is provided in the branch chemical liquid pipe 722a. An opening/closing valve 736 capable of opening and closing the slurry pipe 732 is provided in the slurry pipe 732.

[0059] A first end of the liquid supply pipe 740 is connected to three system pipes: the branch pure water pipe 712a, the branch chemical liquid pipe 722a, and the slurry pipe 732. The liquid supply pipe 740 extends through an interior of the buff arm 600, a center of the buff head 500, and a central portion of the buff pad 502. A second end of the liquid supply pipe 740 opens toward a processing surface of a substrate W. By controlling the opening and closing of the opening/closing valves 718, 728, and 736, the controller 5 may supply, at an arbitrary timing, one of pure water, a chemical liquid, or slurry, or a mixed liquid of any combination thereof, to the processing surface of the substrate W.

[0060] The buffing device 300A may perform buff cleaning on the substrate W by supplying a processing liquid to the substrate W, rotating the buff table 400 about the rotation axis A, pressing the buff pad 502 against the processing surface of the substrate W, and swinging the buff head 500 in a direction indicated by arrow C while rotating the buff head 500 about the rotation axis B. During the buff cleaning process, the substrate W is cleaned and slightly polished. Accordingly, in the present disclosure, the buffing device 300A is included in the polishing apparatus.

[0061] Next, with reference to FIGS. 5 and 6A to 6D, a processing process of the buffing device 300A will be described. FIG. 5 is a view illustrating processing processes on the buff table 400 and the dressing table 810. FIGS. 6A to 6D are views illustrating operations of the buff table 400, the dressing table 810, and the buff head 500. In FIG. 5, the upper row illustrates processes on the buff table 400, and the lower row illustrates processes on the dressing table 810. These processes are performed simultaneously. In addition, circles in the drawings indicate positions of the buff pad 502. For example, during buff cleaning (step S11), the buff pad 502 is positioned on the buff table 400, and during subsequent pad rinsing (step S22), the buff pad 502 moves to the dressing table 810. In FIG. 6, a portion of the buff head 500 is illustrated as a cross-sectional view for convenience of explanation. In addition, in this embodiment, the buff head 500 is provided with a gimbal mechanism and is capable of slightly swinging. The gimbal mechanism will be described later.

[0062] First, buff cleaning is performed on the substrate W on the buff table 400 (step S11). At this time, the buff pad 502 is positioned on the buff table 400. In the buff cleaning, a processing liquid for buff cleaning is supplied from the liquid supply pipe 740, passes through the interior of the buff arm, and is delivered to a central portion of the buff pad 502. Simultaneously, while the rotating buff pad 502 is pressed against the substrate W, the buff arm 600 swings, and the surface of the substrate W rotating together with the buff table 400 is cleaned and polished (see, e.g., FIG. 6A). The buff pad 502 then moves above the dresser 820 for the next process, in which dressing-related operations are subsequently performed. Details thereof will be described later.

[0063] Next, on the buff table 400, wafer rinsing is performed (step S12). The wafer rinsing is a process for cleaning the substrate W with DIW. When the wafer rinsing of the substrate W is completed, the substrate W is taken out from the buff table 400 and transferred to a subsequent step (step S13). Thereafter, the buff table 400 is cleaned by buff table rinsing using DIW (step S14). Thus, a series of processes on the buff table is completed, and a new substrate W for subsequent processing is loaded (step S15), after which the above-described respective processing steps are repeated.

[0064] Meanwhile, in parallel with the above processes, dressing of the buff pad 502 is performed on the dressing table 810. The buff pad 502 (see, e.g., FIG. 6A) used for the buff cleaning (step S11) moves above the dresser 820. At this time, the buff pad 502 is oriented vertically downward. Then, a cleaning liquid (DIW) is supplied from a pad rinsing nozzle 830 disposed obliquely below the buff pad 502, and the surface of the buff pad 502 undergoes pad rinsing (step S22) (see, e.g., FIG. 6B). During the pad rinsing, the buff pad 502 rotates so that its entire surface is evenly cleaned.

[0065] Next, the buff head 500 descends and comes into contact with the dresser 820, and dressing for the buff pad 502 is performed (step S23) (see, e.g., FIG. 6C). The dressing is performed while a processing liquid is being supplied to a central portion of the buff pad 502. During the dressing, both the buff pad 502 and the dresser 820 rotate. In addition, the dressing is performed while centers of rotation of the buff pad 502 and the dresser 820 are offset from each other. This is a measure to prevent specific regions of the buff pad 502 and the dresser 820 from continuously sliding against each other.

[0066] After the dressing is performed, the buff head 500 moves above a brush cleaning mechanism 960, and after the dressing, the buff pad is subjected to brushing (step S24) (see, e.g., FIG. 6D). In addition, the dresser 820 used for the dressing (step S23) is subjected to dresser rinsing (step S21) with a cleaning liquid (DIW) supplied from a dresser cleaning mechanism (not illustrated) provided in the vicinity thereof. During the dresser rinsing, the dressing table 810 rotates so that a surface of the dresser 820 is uniformly cleaned.

Buff Head 500

[0067] Next, a more detailed configuration of the buff head 500 will be described with reference to FIGS. 7 to 9. FIG. 7 is a perspective view illustrating the buffing component 350. FIG. 8 is a cross-sectional view of the buff head 500, illustrating a cross-section along and parallel to a central axis C. FIG. 9 is a cross-sectional plan view of the buff head 500.

[0068]Referring to FIG. 8, the buffing device 300A includes a shaft 510, a boss 511, a drive pin 514, a spring 516, a bolt 517, a buff pad carrier 518, a buff pad 502, a buff head body (e.g., a rotary member) 512, a buff head flange 513, a head support 524, and a stationary member 602. In addition, the shaft 510, the boss 511, the drive pin 514, the spring 516, the bolt 517, the buff pad carrier 518, the buff head body 512, the buff head flange 513, and the head support 524 are included in the buff head 500. The stationary member 602 is fixed to the buff arm 600. Therefore, the stationary member 602 is not rotatable relative to the buff arm 600. The shaft 510 penetrates the stationary member 602 and extends vertically. In addition, the shaft 510 is configured to be rotatable about a central axis C. That is, the shaft 510 is rotatable relative to the stationary member 602. Furthermore, the shaft 510 is hollow. Accordingly, as described above, the buffing device 300A may supply a buffing liquid such as slurry, a chemical liquid, or pure water to a substrate W through an interior of the shaft 510.

[0069]The boss 511 is fixed to the shaft 510. The boss 511 has a cylindrical shape surrounding an entire circumference of the shaft 510. Thus, the boss 511 may rotate together with the shaft 510. A buff head flange 513 is fixed below the boss 511. The buff head flange 513 has a disk shape. The buff head flange 513 includes regions through which the drive pin 514 and the bolt 517 pass. By rotation of the shaft 510 and the boss 511, the buff head flange 513 rotates.

[0070] A head support 524 is fixed below the boss 511. A lower surface of the head support 524 includes a spherical concave surface 525 that is in contact with a buff head body 512. In the meantime, the buff head body 512 includes a spherical convex surface 526 that is in contact with the concave surface 525 of the head support 524. The spherical concave surface 525 of the head support 524 and the spherical convex surface 526 of the buff head body 512 are slidable relative to each other, thereby forming a gimbal mechanism.

[0071]A buff pad carrier 518 is attached to a lower surface of the buff head body 512. The buff pad carrier 518 is configured to allow attachment of the buff pad 502. The buff pad 502 is in direct contact with a substrate W and performs buff cleaning on the substrate W.

[0072] A rotational torque of the buff head flange 513 is transmitted to the buff head body 512 through a drive pin 514. Accordingly, the rotational torque of the shaft 510, the boss 511, and the buff head flange 513 is transmitted to the buff head body 512. When the buff head body 512 is rotationally driven, the buff pad carrier 518 and the buff pad 502 are also rotationally driven. In other words, the buff pad carrier 518 is configured to be rotatable integrally with the shaft 510. As described above, since the gimbal mechanism is provided, the buff head body 512, the buff pad carrier 518, and the buff pad 502 may be tilted relative to the shaft 510 while rotating.

[0073] The bolt 517 is fixed to the buff head body 512 after penetrating the buff head flange 513. A spring 516 is disposed between the head of the bolt 517 and the buff head flange 513. Accordingly, the buff head body 512 is supported by a force of the spring 516. In other words, the spring 516 applies a load to the gimbal motion of the buff head body 512. As a result, unless a force acts on the buff pad 502 from below, the spring 516 maintains a horizontal position of the buff pad 502.

[0074] As illustrated in FIG. 9, three drive pins 514 and three bolts 517 are alternately arranged at equal intervals in a circumferential direction of the buff head 500.

Cover Member 530

[0075] The buffing device 300A further includes a cover member 530 surrounding the buff head 500 (see, e.g., FIG. 8). The cover member 530 functions to prevent a liquid, such as a buff processing liquid, from penetrating an interior of the cover member 530. FIG. 10 is an enlarged view of portion A in FIG. 8. With reference to FIG. 10, the detailed configuration of the cover member 530 will be described.

[0076]As illustrated in FIG. 10, the cover member 530 includes a first lower cover member 540, an upper cover member 550, and a second lower cover member 560. The first lower cover member 540 is attached to the buff head body 512 and extends upward to an upper end 542 thereof from the buff head body 512. The first lower cover member 540 has a cylindrical shape and is disposed so as to surround the central axis C (see, e.g., FIG. 8). The upper cover member 550 is attached to the stationary member 504 and extends downward to a lower end 552 thereof from the stationary member 504. The upper cover member 550 has a cylindrical shape and is disposed so as to surround the central axis C and the first lower cover member 540 (see, e.g., FIG. 8). In addition, the second lower cover member 560 is attached to the first lower cover member 540 and extends upward to an upper end 562 thereof while branching from the first lower cover member 540. The second lower cover member 560 also has a cylindrical shape and is disposed so as to surround the central axis C, the first lower cover member 540, and the upper cover member 550 (see, e.g., FIG. 8). The upper ends 542 and 562 of the first and second lower cover members 540 and 560 are positioned higher than the lower end 552 of the upper cover member 550. In other words, a space is formed between the first lower cover member 540 and the second lower cover member 560. The lower end 552 of the upper cover member 550 is positioned in the space between the first and second lower cover members 540 and 560 without contacting the cover members.

[0077] As described above, in the buffing device 300A, a cleaning liquid (DIW) may be supplied from the pad rinsing nozzle 830 disposed obliquely below the buff pad 502 to clean the buff pad 502 (see, e.g., FIG. 6B). In such a case, as illustrated in FIG. 11, the cleaning liquid flows upward along an outer surface of the second lower cover member 560, and the upper cover member 550 prevents the cleaning liquid from penetrating an interior of the first lower cover member 540. In the meantime, when the buffing device 300A does not include the second lower cover member 560, the cleaning liquid would flow upward along an outer surface of the first lower cover member 540 and may penetrate the interior of the first lower cover member 540, that is, the interior of the cover member 530, through a gap between the first lower cover member 540 and the upper cover member 550. Thus, by further including the second lower cover member 560, the buffing device 300A prevents liquid from penetrating the interior of the cover member 530.

[0078] Next, referring to FIG. 9, the second lower cover member 560 includes a first member 565, a second member 575, and a third member 585. In other words, the second lower cover member 560 includes two or more members and may be divided in a circumferential direction about the central axis C. Therefore, during maintenance or similar operations, an operator may easily remove the second lower cover member 560.

[0079] As described above, in the buffing device 300A, since the second lower cover member 560 is configured to be separable, there is a possibility that a liquid may penetrate an interior of the second lower cover member 560 through respective connection portions of the first member 565, the second member 575, and the third member 585. In contrast, the buffing device 300A includes a feature that suppresses liquid from penetrating the inside from each connection portion. Hereinafter, this feature will be described with reference to FIGS. 9, 12, and 13. FIG. 12 is an enlarged view of portion B in FIG. 9, FIG. 13 is a view illustrating a flow of liquid 900 at the connection portions of the cover member 530. In FIG. 13, a rear end surface 577 of the second member 575 is omitted.

[0080]First, referring first to FIG. 9, a shaft 510 of the buffing device 300A is configured to be rotatable in a counterclockwise rotational direction D. The first member 565, the second member 575, and the third member 585 each have an arcuate shape.

[0081] The first member 565 extends from a front end surface 566 located forward in the rotational direction D to a rear end surface 567 located rearward in the rotational direction D. The front end surface 566 extends from an inner end 568 to an outer end 569 located farther from the central axis C than the inner end 568 (see, e.g., FIG. 12). The inner end 568 is positioned forward in the rotational direction D relative to the outer end 569 so that the front end surface 566 is inclined with respect to a radial line L extending from the central axis C (see, e.g., FIG. 9). Furthermore, the rear end surface 567 faces a front end surface 586 of the third member 585.

[0082] Similarly, the second member 575 extends from a front end surface 576 located forward in the rotational direction D to a rear end surface 577 located rearward in the rotational direction D. The front end surface 576 extends from an inner end 578 to an outer end 579 located farther from the central axis C than the inner end 578. The inner end 578 is positioned forward in the rotational direction D relative to the outer end 579 so that the front end surface 576 is inclined with respect to a radial line extending from the central axis C. Furthermore, the rear end surface 577 faces the front end surface 566 of the first member 565.

[0083] Similarly, the third member 585 extends from a front end surface 586 located forward in the rotational direction D to a rear end surface 587 located rearward in the rotational direction D. The front end surface 586 extends from an inner end 588 to an outer end 589 located farther from the central axis C than the inner end 588. The inner end 588 is positioned forward in the rotational direction D relative to the outer end 589 so that the front end surface 586 is inclined with respect to a radial line extending from the central axis C. Furthermore, the rear end surface 587 faces the front end surface 576 of the second member 575.

[0084] When a liquid 900 is supplied to a connection portion between the first member 565 and the second member 575, as illustrated in FIG. 13, the liquid 900 supplied between the first member 565 and the second member 575 receives a force in a direction away from the central axis C by the rotation of the first member 565 from the front end surface 566, and flows in a direction indicated by arrow 901. Accordingly, in the buffing device 300A, penetration of liquid into the interior from the connection portion between the first member 565 and the second member 575 is suppressed. For the same reason, in the buffing device 300A, penetration of liquid into the interior from the connection portion between the second member 575 and the third member 585 and from the connection portion between the third member 585 and the first member 565 is also suppressed.

[0085] Referring back to FIG. 8, a groove 580 is formed between the first lower cover member 540 and the second lower cover member 560. Therefore, when no measure is taken regarding the groove 580, liquid may accumulate in the groove 580.

[0086] Here, reference is made to FIG. 14. FIG. 14 is an enlarged perspective view of the buff head 500, in which the rear surfaces of the first member 565 and the second member 575 are illustrated by dashed lines. As illustrated in FIG. 14, a discharge hole 590 is formed. As an example, the discharge hole 590 is surrounded by the first member 565, the second member 575, and the first lower cover member 540, and extends vertically (see, e.g., FIG. 12). Therefore, the buffing device 300A may discharge liquid in the groove 580 through the discharge hole 590.

[0087] Similarly, in the buffing device 300A, a discharge hole 591 surrounded by the second member 575, the third member 585, and the first lower cover member 540, and a discharge hole 592 surrounded by the third member 585, the first member 565, and the first lower cover member 540, are formed (see, e.g., FIG. 9). Therefore, the buffing device 300A may also discharge liquid in the groove 580 through the discharge holes 591 and 592.

[0088] In addition, in the buffing device 300A, a bottom surface 593 of the groove 580 is inclined in a circumferential direction such that the liquid inside the groove 580 is guided toward the discharge holes 590, 591, and 592 (see, e.g., FIG. 14). Therefore, in the buffing device 300A, the liquid inside the groove 580 is guided to the discharge holes 590, 591, and 592 along the inclined bottom surface 593. In other words, in the buffing device 300A, liquid is less likely to accumulate inside the groove 580.

[0089] Next, reference is made to FIG. 15. FIG. 15 is a cross-sectional view of the buff head 500 when the buff head 500 is positioned above the dresser 820. As illustrated in FIG. 15, the buffing device 300A includes a head rinsing nozzle 832. The head rinsing nozzle 832 is configured to supply a rinsing liquid (DIW) to the buff head 500 from an obliquely upward direction. Therefore, during the dressing, the buffing device 300A may wash away slurry or contaminants that have adhered to the buff head 500 and the cover member 530 by using the head rinsing nozzle 832.

[0090] Next, referring to FIGS. 7, 10, and 15, the second lower cover member 560 includes an elongated hole 594 communicating with the groove 580. More specifically, the longitudinal direction of the elongated hole 594 coincides with a circumferential direction centered on the central axis C. In the cross-section of FIG. 10, the elongated hole 594 is formed to be inclined obliquely upward as it goes away from the central axis C. Therefore, when liquid is supplied toward the buff head body 512 from an obliquely upward direction, the liquid penetrates into the groove 580 through the elongated hole 594. As a result, the liquid that has entered the groove 580 washes away contaminants inside the groove 580. In other words, during the dressing process, the groove 580 is cleaned by the rinsing liquid supplied from the head rinsing nozzle 832 (see, e.g., FIG. 15).

[0091] As described above, the bottom surface 593 of the groove 580 is inclined in a circumferential direction (see, e.g., FIG. 14). In the buffing device 300A, the highest top portion 595 of the bottom surface 593 of the groove 580 is positioned on the cross-sections of FIGS. 8 and 10 and is located adjacent to the elongated hole 594. When the top portion 595 is not located adjacent to the elongated hole 594, liquid supplied from the elongated hole 594 is less likely to reach the top portion 595. As a result, the top portion 595 may not be cleaned. In contrast, in the buffing device 300A, the top portion 595 is located adjacent to the elongated hole 594. Therefore, liquid may be easily supplied to the top portion 595, and the top portion 595 is more easily cleaned.

[0092] Referring back to FIG. 10, a chamfer is formed on an outer surface of an upper end 542 of the first lower cover member 540. A chamfer is also formed on an outer surface of a lower end 552 of the upper cover member 550. Furthermore, a chamfer is formed on an inner surface of an upper end 562 of the second lower cover member 560.

[0093] Accordingly, during the swing of the buff head 500, the chamfers of the upper end 542, the lower end 552, and the upper end 562 serve as clearances. As a result, even when the buff head body 512 is tilted relative to the stationary member 504 during the swing of the buff head 500, the first lower cover member 540, the upper cover member 550, and the second lower cover member 560 are less likely to interfere with each other (see, e.g., FIG. 16).

[0094] In the above description, the buffing device 300A includes the cover member 530 surrounding the buff head 500. However, the present disclosure is not limited thereto, and the cover member 530 may be applicable to any polishing apparatus. For example, in another embodiment of the present disclosure, the first polishing apparatus 3A, the second polishing apparatus 3B, the third polishing apparatus 3C, or the fourth polishing apparatus 3D may include the cover member 530.

Appendices

[0095] Some or all of the above embodiments may also be described as the following Appendices, but are not limited thereto.

[0096](Appendix 1) A polishing apparatus according to Appendix 1 is a polishing apparatus that includes: a stationary member; a shaft configured to penetrate the stationary member, to extend in a vertical direction, and to rotate about a central axis; a rotary member configured to be rotatable integrally with the shaft; a first lower cover member attached to the rotary member, extending upward from the rotary member to an upper end thereof, and having a cylindrical shape, the first lower cover member being disposed to surround the central axis; an upper cover member attached to the stationary member, extending downward from the stationary member to a lower end thereof, and having a cylindrical shape, the upper cover member being disposed to surround the central axis and the first lower cover member; and a second lower cover member attached to the first lower cover member, extending upward from the first lower cover member to an upper end thereof while branching from the first lower cover member, and having a cylindrical shape, the second lower cover member being disposed to surround the central axis, the first lower cover member, and the upper cover member.

[0097](Effect) In the polishing apparatus according to Appendix 1, a liquid is less likely to penetrate the interior of the cover through a gap between the first lower cover member and the upper cover member.

[0098] (Appendix 2) A polishing apparatus according to Appendix 2 is the polishing apparatus set forth in Appendix 1, in which the upper end of the first lower cover member and the upper end of the second lower cover member are positioned higher than the lower end of the upper cover member.

[0099] (Appendix 3) A polishing apparatus according to Appendix 3 is the polishing apparatus set forth in Appendix 1 or 2, in which the second lower cover member includes two or more members and is configured to be separable in a circumferential direction about a central axis.

[0100](Effect) In the polishing apparatus according to Appendix 3, since the second lower cover member is divided, an operator may easily remove the second lower cover member during maintenance or similar operations.

[0101](Appendix 4) A polishing apparatus according to Appendix 4 is the polishing apparatus set forth in Appendix 3, in which the second lower cover member includes first and second members, which have an arcuate shape in a plan view, the first member extends from a front end surface located forward in a rotational direction of the rotary member to a rear end surface located rearward in the rotational direction; the front end surface extends from an inner end to an outer end located farther from the central axis than the inner end; the inner end is positioned forward in the rotational direction relative to the outer end such that, in a plan view, the front end surface is inclined with respect to a radial line extending from the central axis; and the second member has a rear end surface facing the front end surface of the first member.

[0102] (Effect) In the polishing apparatus according to Appendix 4, penetration of a liquid into the inside from a connection portion between the first member and the second member is suppressed.

[0103](Appendix 5) A polishing apparatus according to Appendix 5 is the polishing apparatus set forth in any one of Appendices 1 to 4, in which a groove is formed between the first lower cover member and the second lower cover member, and a discharge hole is formed to discharge liquid in the groove to an outside of the groove.

[0104] (Effect) In the polishing apparatus according to Appendix 5, liquid in the groove between the first lower cover member and the second lower cover member may be discharged through the discharge hole.

[0105](Appendix 6) A polishing apparatus according to Appendix 6 is the polishing apparatus set forth in Appendix 5, in which a bottom surface of the groove is inclined in a circumferential direction such that liquid inside the groove is guided toward the discharge hole.

[0106] (Effect) In the polishing apparatus according to Appendix 6, liquid is less likely to accumulate inside the groove.

[0107](Appendix 7) A polishing apparatus according to Appendix 7 is the polishing apparatus set forth in Appendix 5, in which the second lower cover member includes an elongated hole communicating with the groove, a longitudinal direction of the elongated hole coincides with a circumferential direction centered on the central axis, and in a cross-sectional view passing through and parallel to the central axis, the long hole is formed to be inclined obliquely upward as a distance from the central axis increases.

[0108] (Effect) In the polishing apparatus according to Appendix 7, when a liquid is supplied toward the rotary member from an obliquely upward direction, contaminants in the groove may be washed away by the liquid penetrating into the groove.

[0109](Appendix 8) A polishing apparatus according to Appendix 8 is the polishing apparatus set forth in Appendix 7, in which a bottom surface of the groove is inclined in a circumferential direction such that liquid inside the groove is guided toward the discharge hole, and the highest top portion of the bottom surface of the groove is positioned on the cross-section and is located adjacent to the long hole.

[0110](Effect) In the polishing apparatus according to Appendix 8, liquid may be easily supplied to the top portion.

[0111] (Appendix 9) A polishing apparatus according to Appendix 9 is the polishing apparatus set forth in any one of Appendices 1 to 8, in which a chamfer is formed on an outer surface of the upper end of the first lower cover member, a chamfer is formed on an outer surface of the lower end of the upper cover member, and a chamfer is formed on an inner surface of the upper end of the second lower cover member.

[0112](Effect) In the polishing apparatus according to Appendix 9, even when the rotary member is tilted relative to the stationary member, the first lower cover member, the upper cover member, and the second lower cover member are less likely to interfere with each other.

[0113](Appendix 10) A polishing apparatus according to Appendix 10 is the polishing apparatus set forth in any one of Appendices 1 to 9, further including a buff pad carrier configured to be rotatable integrally with the shaft and to allow attachment of a buff pad.

[0114] From the foregoing, it will be appreciated that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the following claims.