POLISHING APPARATUS

- EBARA CORPORATION

A technology that can clean a bottom surface of a dresser while inhibiting a cleaning solution discharged from a cleaning nozzle from splashing in a direction of a polishing pad. A polishing apparatus 1 includes a polishing table 2, a top ring 3, a dresser 10, at least one cleaning nozzle 20, and a dresser rotation mechanism 32. The at least one cleaning nozzle discharges a cleaning solution Lq in a fan shape and in a direction away from a polishing pad Pd, and an intersection point IP where a discharge central axis XL2 of the cleaning solution intersects with a bottom surface 11 of the dresser is positioned closer to the at least one cleaning nozzle than a center line CL1 of the bottom surface of the dresser. The at least one cleaning nozzle discharges the cleaning solution such that a part of the cleaning solution discharged from the cleaning nozzle and contacting the bottom surface of the dresser moves and passes through the center C1 of the bottom surface of the dresser.

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Description
CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority from Japanese Patent Application No. 2023-181698 filed on Oct. 23, 2023. The entire disclosure including the descriptions, the claims, the drawings, and the abstracts in Japanese Patent Application No. 2023-181698 is herein incorporated by reference.

BACKGROUND 1. Technical Field

The present invention relates to a polishing apparatus.

2. Related Art

Conventionally, a polishing apparatus is known to include a polishing table for holding a polishing pad for polishing a substrate, a top ring for holding the substrate, a dresser for dressing the polishing pad, and a cleaning nozzle for cleaning a bottom surface of the dresser by discharging a cleaning solution toward the bottom surface of the dresser (see, for example, PTLs 1 and 2).

CITATION LIST Patent Literature

    • PTL 1: Japanese Unexamined Patent Application Publication No. H09-254018
    • PTL 2: Japanese Unexamined Patent Application Publication No. H11-347917

SUMMARY

In the case of the conventional polishing apparatus described above, there is a risk that the cleaning solution discharged from the cleaning nozzle may scatter in a direction of the polishing pad. In this case, a quality of the substrate polishing may deteriorate due to this splashed cleaning solution.

The present invention has been made in view of the above, and one of its objects is to provide a technique that can clean the bottom surface of a dresser while inhibiting a cleaning solution discharged from a cleaning nozzle from scattering in the direction of a polishing pad.

Aspect 1

To achieve the above-described object, a polishing apparatus according to one aspect of the present invention includes a polishing table, a top ring, a dresser, at least one cleaning nozzle, and a dresser rotation mechanism. The polishing table is configured to hold a polishing pad for polishing a substrate. The top ring is configured to hold the substrate. The dresser is configured to dress the polishing pad. The dresser is movable between a dressing position in which the dresser is positioned above the polishing pad and a standby position in which the dresser is not positioned above the polishing pad. The at least one cleaning nozzle is configured to discharge a cleaning solution from below the dresser to a bottom surface of the dresser to clean the bottom surface when the dresser is in the standby position. The dresser rotation mechanism is configured to rotate the dresser during cleaning of the dresser with the cleaning solution. The at least one cleaning nozzle discharges the cleaning solution in a fan shape and in a direction away from the polishing pad. An intersection point where a discharge central axis as a central axis of a fan shape of the discharged cleaning solution intersects with the bottom surface of the dresser is positioned closer to the at least one cleaning nozzle than the center line of the bottom surface of the dresser. The center line is perpendicular to the discharge central axis, in plan view. The at least one cleaning nozzle discharges the cleaning solution such that a part of the cleaning solution discharged from the cleaning nozzle and brought into contact with the bottom surface of the dresser moves and passes through the center of the bottom surface of the dresser.

According to the aspect, the cleaning nozzle discharges the cleaning solution in the direction away from the polishing pad. Thus, the bottom surface of the dresser can be cleaned while inhibiting the cleaning solution discharged from the cleaning nozzle from scattering in the direction of the polishing pad.

According to the aspect, the cleaning solution discharged from the cleaning nozzle can be brought into contact with a side closer to the cleaning nozzle than the center line of the bottom surface of the dresser in plan view, and a part of the cleaning solution in contact with the bottom surface of the dresser can pass through the center of the bottom surface of the dresser, thereby cleaning the bottom surface of the dresser while suppressing insufficient cleaning of the center of the bottom surface of the dresser.

Aspect 2

In the above-described aspect 1, the at least one cleaning nozzle may include a plurality of cleaning nozzles.

Aspect 3

In the above-described aspect 2, the plurality of cleaning nozzles may discharge the cleaning solution such that when the cleaning solution discharged from the plurality of cleaning nozzles contacts the bottom surface of the dresser, the pressure applied to the bottom surface from the cleaning solution is partially increased.

This aspect allows the bottom surface of the dresser to be effectively cleaned.

Aspect 4

In the above-described aspect 3, the plurality of cleaning nozzles may be arranged such that the cleaning solution discharged from the plurality of cleaning nozzles contacts an entire surface of the bottom surface of the rotating dresser, or contacts a portion of the bottom surface of the rotating dresser and subsequently moves over the entire surface of the bottom surface.

This aspect allows the entire surface of the bottom surface of the dresser to be effectively cleaned.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic plan view of a schematic configuration of a polishing apparatus according to an embodiment;

FIG. 2 is a schematic side view of a dresser and a cleaning nozzle according to the embodiment;

FIG. 3 is a schematic plan view illustrating a positional relationship between the dresser and the cleaning nozzle during an execution of a dresser cleaning process according to the embodiment;

FIG. 4 is a schematic plan view for describing a state of a cleaning solution discharged from a discharge port and brought into contact with a bottom surface of the dresser according to the embodiment;

FIG. 5 is a schematic plan view illustrating the cleaning nozzle of the polishing apparatus according to Modification 1 of the embodiment, viewed from the discharge port side;

FIG. 6 is a schematic plan view illustrating a positional relationship between the dresser and the cleaning nozzle during the execution of the dresser cleaning process according to Modification 1 of the embodiment;

FIG. 7 is a schematic plan view for describing a state of the cleaning solution discharged from the discharge port and brought into contact with the bottom surface of the dresser according to Modification 1 of the embodiment;

FIG. 8 is a schematic plan view illustrating the cleaning nozzle of the polishing apparatus according to Modification 2 of the embodiment, viewed from the discharge port side;

FIG. 9 is a schematic plan view illustrating a positional relationship between the dresser and the cleaning nozzle during the execution of the dresser cleaning process according to Modification 2 of the embodiment;

FIG. 10 is a schematic plan view for describing a state of the cleaning solution discharged from the discharge port and brought into contact with the bottom surface of the dresser according to Modification 2 of the embodiment;

FIG. 11 is a schematic plan view illustrating the cleaning nozzle of the polishing apparatus according to Modification 3 of the embodiment, viewed from the discharge port side;

FIG. 12 is a schematic plan view illustrating a positional relationship between the dresser and the cleaning nozzle during the execution of the dresser cleaning process according to Modification 3 of the embodiment;

FIG. 13 is a view for describing a result of cleaning the bottom surface of the dresser using the polishing apparatus according to the embodiment;

FIG. 14A is a schematic diagram illustrating an example of a shape of the discharge port of the cleaning nozzle according to the embodiment;

FIG. 14B is a schematic diagram illustrating an example of a shape of the discharge port of the cleaning nozzle according to the embodiment; and

FIG. 14C is a schematic diagram illustrating an example of a shape of the discharge port of the cleaning nozzle according to the embodiment.

 DESCRIPTION OF EXEMPLARY EMBODIMENTS Embodiment

The following describes embodiments of the present invention with reference to the drawings. Note that the drawings are schematically illustrated to facilitate understanding of features, and dimensional proportions and the like of each constituent element are not necessarily the same as the actual ones. In some drawings, orthogonal coordinates of X-Y-Z are illustrated. Among the orthogonal coordinates, the Z-direction corresponds to an upper side, and the −Z-direction corresponds to a lower side (direction in which gravity acts).

FIG. 1 is a schematic plan view of a schematic configuration of a polishing apparatus 1 according to an embodiment. The polishing apparatus 1 of this embodiment is a polishing apparatus capable of performing a chemical mechanical polishing (CMP), as one example. Specifically, the polishing apparatus 1 illustrated in FIG. 1 includes a polishing table 2, a top ring 3, a dresser 10, a cleaning nozzle 20, and a controller 40.

The controller 40 is a device for integrally controlling an operation of the polishing apparatus 1. Specifically, the controller 40 according to the embodiment includes a microcomputer. The microcomputer includes a processor 41, a storage device 42 as a non-transitory storage medium, and the like. In the controller 40, the processor 41 controls the operation of the polishing apparatus 1 by operating based on the commands of a program stored in the storage device 42.

The polishing table 2 holds a polishing pad Pd. Specifically, the polishing table 2 according to the embodiment includes a disk-shaped member, and the polishing pad Pd is attached to a top surface of the disk. During the polishing of a substrate Wf, the substrate Wf as a material to be polished is pressed against the top surface of the polishing pad Pd. In other words, the top surface of the polishing pad Pd corresponds to a polishing surface for polishing the substrate Wf.

The polishing table 2 rotates driven by a rotation motor or another driving mechanism (not illustrated). A rotational movement of the polishing table 2 is controlled by the controller 40. A direction of rotation of the polishing table 2 may be clockwise or counterclockwise in plan view. An example of the direction of rotation of the polishing table 2 is illustrated in FIG. 1 by “R1.”

The type of the polishing pad Pd is not specifically limited, and a variety of polishing pads can be used, including a hard foam type polishing pad, a non-woven type polishing pad, a suede type polishing pad, and the like.

The top ring 3 is a member for holding the substrate Wf. In FIG. 1, the substrate Wf is held on the bottom surface of the top ring 3. The top ring 3 is configured to rotate while pressing the bottom surface of the substrate Wf (that is, the surface to be polished) against the polishing pad Pd. Specifically, the top ring 3 according to the embodiment is driven by a driving mechanism for the top ring 3 (not illustrated), as an example, and rotates in a predetermined rotation direction. In FIG. 1, an example of the direction of rotation of the top ring 3 is illustrated by “R2.”

During the polishing of the substrate Wf, a polishing solution (that is, polishing slurry) containing a polishing material is supplied to the polishing pad Pd. The polishing apparatus 1 polishes the substrate Wf in a presence of this polishing solution while rubbing the substrate Wf against the polishing pad Pd. The substrate Wf illustrated in FIG. 1 is a round substrate as an example, but the shape of the substrate Wf is not limited thereto. The shape of the substrate Wf may be square or any other shape.

The dresser 10 is a device for dressing the polishing surface (the top surface) of the polishing pad Pd. Abrasive grains, such as diamonds, for example, are arranged on a bottom surface 11 of the dresser 10. The dresser 10 dresses the polishing surface of the polishing pad Pd by bringing its bottom surface 11 into contact with the polishing surface of the polishing pad Pd when dressing the pad Pd. In other words, the bottom surface 11 of the dresser 10 functions as a “dressing surface” for dressing the polishing pad Pd.

The dresser 10 according to the embodiment is connected to an arm rotation mechanism 31 via an arm 30. The arm rotation mechanism 31 rotates under an instruction of the controller 40 to move the dresser 10, which is connected to the arm rotation mechanism 31 via the arm 30, between a “dressing position P1” and a “standby position P2.”

In the dressing position P1, the dresser 10 is positioned above the polishing pad Pd. On the other hand, in the standby position P2, the dresser 10 is not positioned above the polishing pad Pd, but is positioned at a side of the polishing pad Pd, for example. The dressing of the polishing pad Pd by the dresser 10 is executed with the dresser 10 positioned in the dressing position P1. On the other hand, the “dresser cleaning process” described later is executed with the dresser 10 positioned in the standby position P2.

The polishing apparatus 1 according to the embodiment also includes a dresser rotation mechanism 32 for rotating the dresser 10. Specifically, the dresser rotation mechanism 32 is configured to rotate the dresser 10 upon receiving instructions from the controller 40. In FIG. 1, an example of the direction of rotation of the dresser 10 is illustrated by “R3.” The specific configuration of the dresser rotation mechanism 32 is not particularly limited, and a known configuration such as a rotation motor, for example, can be used.

The dresser rotation mechanism 32 according to the embodiment rotates the dresser 10 a plurality of times, at least when cleaning the dresser 10 (that is, during the execution of the “dresser cleaning process” described later). The dresser rotation mechanism 32 may also rotate the dresser 10 during the dressing of the polishing pad Pd by the dresser 10. The dresser rotation mechanism 32 according to the embodiment is configured to rotate together with the arm 30 and the dresser 10 when the arm 30 and the dresser 10 rotate about the arm rotation mechanism 31.

The rotation speed of the dresser 10 by the dresser rotation mechanism 32 is not particularly limited and can be set accordingly. To give an example of the rotational speed of the dresser 10, a value of 0.5 rotation per second (0.5 rpm/sec) or more can be used, preferably a value of one rotation per second (1 rpm/sec) or more.

FIG. 2 illustrates a schematic side view of the dresser 10 and the cleaning nozzle 20. The number of the cleaning nozzles 20 of the polishing apparatus 1 may be one or more. In other words, the polishing apparatus 1 need only include at least one cleaning nozzle 20. The polishing apparatus 1 of this embodiment includes one (single) cleaning nozzle 20 as an example. The cleaning nozzle 20 is held by a nozzle holder 25 as an example. As an example of this, the cleaning nozzle 20 of this embodiment is held on an inclined surface 25a, for example, of the nozzle holder 25.

The cleaning nozzle 20 is configured to clean the bottom surface 11 of the dresser 10 with a cleaning solution Lq while the dresser 10 is in the standby position P2 (this cleaning process with the cleaning solution Lq is called the “dresser cleaning process”).

Specifically, the cleaning nozzle 20 according to the embodiment includes a discharge port 21 that discharges the cleaning solution Lq. The cleaning nozzle 20 discharges (or injects) the cleaning solution Lq from this discharge port 21 toward the bottom surface 11 of the dresser 10 upon receiving instructions from the controller 40. Specifically, the cleaning nozzle 20 discharges the cleaning solution Lq for a predetermined time upon receiving instructions from the controller 40 when the dresser cleaning process is executed. The specific value of this predetermined time is not particularly limited, but for example, a time of 5 seconds or longer can be used.

The cleaning nozzle 20 may be communicated via a pipe 52, for example, with a storage tank 50 for temporarily storing the cleaning solution Lq and a discharge pump 51 for pumping the cleaning solution Lq stored in the storage tank 50 to the cleaning nozzle 20, as illustrated in FIG. 2. The discharge pressure and discharge volume of the cleaning solution Lq from the cleaning nozzle 20 can be adjusted, for example, by adjusting a size of the discharge port 21 of the cleaning nozzle 20, by adjusting output of the discharge pump 51, or by setting a regulator in the middle of the piping to cleaning nozzle 20. The specific type of the cleaning solution Lq is not particularly limited, and for example, a water (specifically, pure water) or the like can be used.

As illustrated in FIG. 2, the cleaning nozzle 20 according to the embodiment is positioned with the central axis of the discharge port 21 (the “discharge central axis XL2” described below) not intersecting with the central axis XL1 of the dresser 10, but in front of it off this central axis XL1. The cleaning nozzle 20 is positioned lower than the bottom surface 11 of the dresser 10. The discharge port 21 of the cleaning nozzle 20 discharges the cleaning solution Lq from the lower side than the dresser 10 toward the bottom surface 11 of the dresser 10. In other words, the discharge port 21 discharges the cleaning solution Lq at an oblique upward angle. The discharge port 21 may discharge the cleaning solution Lq as a mist, for example.

The discharge port 21 of this embodiment discharges the cleaning solution Lq in a fan shape. The central axis of this discharged fan shaped cleaning solution Lq (in other words, the central axis of the fan shaped discharge range of the discharged cleaning solution Lq) is called the “discharge central axis XL2.” This discharge central axis XL2 is also the central axis of the cleaning nozzle 20, and more specifically, the central axis of the discharge port 21.

As the cleaning nozzle 20 capable of discharging the cleaning solution Lq in such a fan shape, for example, a known cleaning nozzle such as the “fan shaped nozzle” manufactured and sold by H. Ikeuchi & Co., Ltd can be used. The discharge angle (the center angle of the fan shape) at which the cleaning nozzle 20 discharges the fan shaped cleaning solution Lq is not particularly limited, but a value selected from a range of 70 degrees or more and 130 degrees or less can be used, for example.

FIG. 14A, FIG. 14B, and FIG. 14C are schematic diagrams illustrating examples of shape of the discharge port 21 of the cleaning nozzle 20. Specifically, FIGS. 14A to 14C illustrate the cleaning nozzles 20 viewed from a side of the discharge port 21. For example, the discharge port 21 may be circular as illustrated in FIG. 14A, slit-shaped as illustrated in FIG. 14B, or elliptical as illustrated in FIG. 14C. The shape around the discharge port may, for example, be a concave shape such that the discharged liquid is discharged in a fan shape.

FIG. 3 is a schematic plan view of a positional relationship between the dresser 10 and the cleaning nozzle 20 when the dresser cleaning process is executed. Specifically, FIG. 3 schematically illustrates the bottom surface 11 of the dresser 10 viewed from an upper side (viewed from the upper side as if the dresser 10 were transparent). The discharge port 21 illustrated in FIG. 3 is a projection of the discharge port 21 of the cleaning nozzle 20 onto the bottom surface 11 of the dresser 10. The polishing pad Pd (which is not illustrated in FIG. 3) is positioned on a Y-direction side with respect to the dresser 10 in FIG. 3.

A transverse center line CL1 of the dresser 10 is illustrated in FIG. 3. This transverse center line CL1 is the center line that passes through the center C1 of the bottom surface 11 of the dresser 10 and is perpendicular to the discharge central axis XL2 in plan view. A longitudinal center line CL2 of the dresser 10 is also illustrated in FIG. 3. This longitudinal center line CL2 is the center line that passes through the center C1 of the bottom surface 11 of the dresser 10 and is perpendicular to the transverse center line CL1.

Referring to FIG. 3 and the above-described FIG. 2, the discharge port 21 of the cleaning nozzle 20 discharges the cleaning solution Lq in the direction away from the polishing pad Pd (−Y-direction in FIG. 2 and FIG. 3).

A intersection point IP where the discharge central axis XL2 intersects with the bottom surface 11 of the dresser 10 is positioned closer to the cleaning nozzle 20 (specifically, the discharge port 21) than the center line of the bottom surface 11 of the dresser 10 (in this embodiment, the transverse center line CL1) in plan view. In other words, this intersection point IP is positioned between the transverse center line CL1 and the discharge port 21 in plan view. In other words, the intersection point IP is positioned on an opposite side in the discharge direction of the cleaning solution Lq (the side where the cleaning solution Lq enters) with respect to the transverse center line CL1.

This allows the cleaning solution Lq discharged from the discharge port 21 of the cleaning nozzle 20 to contact the side closer to the cleaning nozzle 20 than the center line of the bottom surface 11 of the dresser 10 (the transverse center line CL1) in plan view, as illustrated in FIG. 3.

Specifically, in this embodiment, the “first region Re1,” which is the region where the discharged cleaning solution Lq first contacts the bottom surface 11 of the dresser 10, is elliptical in shape. This first region Re1 is positioned closer to the cleaning nozzle 20 than the transverse center line CL1.

The fan shaped cleaning solution Lq discharged from the discharge port 21 encompasses, in plan view, a “triangle” with a vertex corresponding to the discharge port 21, a bottom side ts3 passing through the intersection point IP, and two sides (sides ts1 and ts2) connecting the discharge port 21 and both ends (one end e1 and the other end e2) of the bottom side ts3. In this embodiment, the lengths of the sides ts1 and ts2 are equal as an example.

One end e1 and the other end e2 of the bottom side ts3 are positioned on a side closer to the discharge port 21 (the side where the discharge port 21 is positioned) than the transverse center line CL1 in plan view. One end e1 of the bottom side ts3 is positioned on the side opposite to the side where the discharge port 21 is positioned (the side where the discharge port 21 is not positioned) relative to the longitudinal center line CL2. On the other hand, the other end e2 of the bottom side ts3 is positioned on the side where the discharge port 21 is positioned with respect to the longitudinal center line CL2 and outside the bottom surface 11 of the dresser 10. As a result, the cleaning nozzle 20 according to the embodiment discharges the cleaning solution Lq such that the cleaning solution Lq discharged from the discharge port 21 of the cleaning nozzle 20 contacts the entire surface of the bottom surface 11 of the rotating dresser 10.

As mentioned above, the other end e2 of the bottom side ts3 according to the embodiment is positioned outside of the bottom surface 11 of the dresser 10 in plan view, but it is not limited to this configuration. The other end e2 of the bottom side ts3 may be positioned inside the bottom surface 11 of the dresser 10 in plan view. However, the case where the other end e2 of the bottom side ts3 is positioned outside the bottom surface 11 of the dresser 10 in plan view is preferred over the case where it is positioned inside of this bottom surface 11 in that it is easier to bring the cleaning solution Lq in contact with a wider area of the bottom surface 11 of the dresser 10.

FIG. 4 is a schematic plan view for describing a state of the cleaning solution Lq discharged from the discharge port 21 and brought into contact with the bottom surface 11 of the dresser 10. Due to the horizontal velocity component of the cleaning solution Lq discharged from the discharge port 21 and the like, the cleaning solution Lq that comes into contact with the first region Re1 then moves across the bottom surface 11 of the dresser 10 and passes through the second region Re2 (hatched for easy viewing) illustrated in FIG. 4. The cleaning solution Lq then falls from the bottom surface 11 of the dresser 10.

As illustrated in FIG. 4, in this embodiment, the second region Re2 includes the center C1 of the bottom surface 11 of the dresser 10. In other words, the cleaning nozzle 20 according to the embodiment discharges the cleaning solution Lq such that a part of the cleaning solution Lq that is discharged from the cleaning nozzle 20 and contacts the bottom surface 11 of the dresser 10 moves and passes through the center C1 of the bottom surface 11 of the dresser 10. This can be achieved, for example, by adjusting the angle of discharge and the discharge pressure of the cleaning solution Lq from the cleaning nozzle 20 as appropriate.

According to the embodiment described above, the cleaning nozzle 20 discharges the cleaning solution Lq in the direction away from the polishing pad Pd. Thus, the cleaning solution Lq discharged from the discharge port 21 of the cleaning nozzle 20 allows cleaning the entire bottom surface 11 of the dresser 10 while suppressing the scatter in the direction of the polishing pad Pd.

This can suppress the deterioration of the polishing quality of the substrate Wf caused by the cleaning solution Lq scattered in the direction of the polishing pad Pd. Specifically, the polishing quality of the substrate Wf can be inhibited from deteriorating due to the cleaning solution Lq scattered in the direction of the polishing pad Pd adhering to the polishing pad Pd or mixing with the polishing solution on the polishing pad Pd.

According to this embodiment, the cleaning solution Lq discharged from the discharge port 21 of the cleaning nozzle 20 can be brought into contact with the side closer to the cleaning nozzle 20 than the center line of the bottom surface 11 of the dresser 10 (the transverse center line CL1) in plan view, and a part of the cleaning solution Lq in contact with the bottom surface 11 of the dresser 10 moves and passes through the center C1 of the bottom surface 11 of the dresser 10. This allows the bottom surface 11 of the dresser 10 to be cleaned while inhibiting the center C1 of the bottom surface 11 of the dresser 10 from being insufficiently cleaned.

Modification 1

A polishing apparatus 1a according to Modification 1 of the embodiment is described below. The polishing apparatus 1a according to this modification differs from the above-described polishing apparatus 1 according to the embodiment in that the polishing apparatus 1a includes a plurality of cleaning nozzles. FIG. 5 is a schematic plan view of the cleaning nozzles of the polishing apparatus 1a according to this modification, viewed from the discharge port side. Specifically, FIG. 5 schematically illustrates the cleaning nozzles of this modification viewed from the upper side along the discharge central axis XL2 described above.

The polishing apparatus 1a according to this modification includes two cleaning nozzles, specifically cleaning nozzles 20a, 20b, as an example of the plurality of cleaning nozzles. The cleaning nozzle 20a has a discharge port 21a, and the cleaning nozzle 20b has a discharge port 21b.

In FIG. 5, the discharge ports 21a, 21b are illustrated as circular to simplify the illustration, but the actual shapes of the discharge ports 21a, 21b are not limited to circular. For example, the discharge ports 21a, 21b may be slit or ellipse-shaped, and the shape around the discharge port may be concave such that the discharged liquid is discharged in a fan shape. The cleaning nozzle 20a and the cleaning nozzle 20b illustrated in FIG. 5 are held by the nozzle holder 25 as an example. As an example of this, the cleaning nozzle 20a and the cleaning nozzle 20b illustrated in FIG. 5 are held on the inclined surface 25a, for example, of the nozzle holder 25.

FIG. 6 is a schematic plan view of a positional relationship between the dresser 10 and the cleaning nozzles when the dresser cleaning process according to this modification is executed. Referring to FIG. 5 and FIG. 6, the plurality of cleaning nozzles according to this modification are arranged in a direction along the transverse center line CL1 in plan view.

The cleaning nozzles 20a, 20b according to this modification discharge the cleaning solution Lq such that the pressure applied from the cleaning solution Lq to the bottom surface 11 is partially increased when the cleaning solution Lq contacts the bottom surface 11 of the dresser 10. This allows the bottom surface 11 of the dresser 10 to be effectively cleaned.

Specifically, with reference to FIG. 6, the cleaning nozzles 20a, 20b according to this modification discharge the cleaning solution Lq such that a distance that the discharged cleaning solution Lq travels before it contacts the bottom surface 11 of the dresser 10 (that is, the “discharge distance (or injection distance) of the cleaning solution Lq”) is short at some locations while this discharge distance is long at some locations.

More specifically, the two sides (the sides ts1 and ts2) of a triangle of the fan shaped cleaning solution Lq discharged from the discharge ports 21a, 21b are constituted of the side ts1 (that is, the “short side”), which has a short distance from the discharge ports 21a, 21b to the bottom surface 11 of the dresser 10, and the side ts2 (that is, the “long side”), which has a long distance from the discharge ports 21a, 21b to the bottom surface 11 of the dresser 10. The discharge distance (the injection distance) of the cleaning solution Lq at the side ts1 (short side) is shorter than the discharge distance of the cleaning solution Lq at the side ts2 (long side).

This modification can be configured by tilting the cleaning nozzle at a predetermined angle clockwise when viewed from the discharge port side such that a slit direction of the discharge port is not parallel to the transverse center line CL1.

According to this configuration, this modification allows a pressure applied to the bottom surface 11 of the dresser 10 from the cleaning solution Lq in contact with a region between the one end e1 and the intersection point IP in the first region Re1 (that is, the “contact pressure (or impact pressure)”) to be higher than a pressure applied to the bottom surface 11 of the dresser 10 from the cleaning solution Lq in contact with a region between the intersection point IP and the other end e2 in the first region Re1.

As illustrated in FIG. 6, the cleaning nozzle 20b is preferred to be arranged such that the cleaning solution Lq discharged from the discharge port 21b of the cleaning nozzle 20b interferes as little as possible with the cleaning solution Lq discharged from the discharge port 21a of the cleaning nozzle 20a.

As illustrated in FIG. 6, the plurality of cleaning nozzles 20a, 20b are preferred to be arranged such that the cleaning solution Lq discharged from these cleaning nozzles contacts the entire surface of the bottom surface 11 of the rotating dresser 10, or partially contacts the bottom surface 11 and moves over the entire surface of the bottom surface 11 of the rotating dresser 10 when the dresser cleaning process is executed. This allows effective cleaning of the entire surface of the bottom surface 11 of the dresser 10.

FIG. 7 is a schematic plan view for describing a state of the cleaning solution Lq discharged from the discharge port 21a and brought into contact with the bottom surface 11 of the dresser 10. As illustrated in FIG. 7, the cleaning solution Lq that is discharged from the discharge port 21a and contacts the first region Re1 then moves across the bottom surface 11 of the dresser 10 and passes through the second region Re2. In FIG. 7, the second region of the cleaning solution Lq discharged from the discharge port 21b is omitted.

As illustrated in FIG. 7, also in this modification, similarly to the above-described embodiment, the second region Re2 includes the center C1 of the bottom surface 11 of the dresser 10. In other words, in this modification, the cleaning nozzle 20a discharges the cleaning solution Lq such that a part of the cleaning solution Lq that is discharged from the cleaning nozzle 20a and contacts the bottom surface 11 of the dresser 10 moves and passes through the center C1 of the bottom surface 11 of the dresser 10.

In this modification, the same effects can be achieved similarly to the above-described embodiments.

Modification 2

A polishing apparatus 1b according to Modification 2 of the embodiment is described below. The polishing apparatus 1b according to this modification differs from the above-described polishing apparatus 1 according to the embodiment in that the polishing apparatus 1b includes a plurality of cleaning nozzles. FIG. 8 is a schematic plan view of the cleaning nozzles of the polishing apparatus 1b according to this modification, viewed from the discharge port side (viewed from the same side as in FIG. 5). The polishing apparatus 1b includes four cleaning nozzles, specifically cleaning nozzles 20c, 20d, 20e, 20f, as an example of the plurality of cleaning nozzles.

The cleaning nozzle 20c has a discharge port 21c, the cleaning nozzle 20d has a discharge port 21d, the cleaning nozzle 20e has a discharge port 21e, and the cleaning nozzle 20f has a discharge port 21f.

In FIG. 8, the discharge ports 21c, 21d, 21e, 21f are illustrated as circular shapes to simplify the illustration, but the actual shapes of the discharge ports 21c, 21d, 21e, 21f are not limited to circular shapes. For example, the discharge ports 21c, 21d, 21e, 21f may be slit or ellipse-shaped, and the shape around the discharge port may be concave such that the discharged liquid is discharged in a fan shape.

FIG. 9 is a schematic plan view of a positional relationship between the dresser 10 and the cleaning nozzles when the dresser cleaning process according to this modification is executed. Referring to FIG. 8 and FIG. 9, the plurality of cleaning nozzles according to this modification are also positioned in a direction along the transverse center line CL1 in plan view.

Referring to FIG. 9, the discharge ports 21c, 21d, 21e, 21f according to this modification are positioned on the Y-direction side with respect to the transverse center line CL1 in plan view. The discharge ports 21c, 21d are positioned on the −X-direction side with respect to the longitudinal center line CL2 in plan view, and the discharge ports 21e, 21f are positioned on the X-direction side with respect to the longitudinal center line CL2 in plan view. The discharge port 21c is positioned on the Y-direction side with respect to the discharge port 21d in plan view, and the discharge port 21e is positioned on the Y-direction side with respect to the discharge port 21f in plan view.

The plurality of cleaning nozzles 20c, 20d, 20e, 20f are arranged such that when the dresser cleaning process is executed, the cleaning solution Lq discharged from these cleaning nozzles contacts the entire surface of the bottom surface 11 of the rotating dresser 10, or contacts a portion of the bottom surface 11 and moves over the entire surface. This allows effective cleaning of the entire surface of the bottom surface 11 of the dresser 10.

In this modification, similarly to the above-described examples in FIG. 3 and FIG. 4, the cleaning nozzles 20c, 20d, 20e, 20f discharge the cleaning solution Lq in a fan shape about the discharge central axis XL2 and in a direction away from the polishing pad Pd in plan view. The intersection point IP where the discharge central axis XL2 intersects with the bottom surface 11 of the dresser 10 is positioned closer to the cleaning nozzles 20c, 20d, 20e, 20f than the transverse center line CL1 on the bottom surface 11 of the dresser 10 in plan view.

FIG. 10 is a schematic plan view for describing a state of the cleaning solution Lq discharged from the discharge port 21d and the discharge port 21f and brought into contact with the bottom surface 11 of the dresser 10. In FIG. 10, the second region of the cleaning solution Lq discharged from discharge ports 21c, 21e is omitted. As can be seen from the fact that the second region Re2 includes the center C1 of the bottom surface 11 of the dresser 10, the cleaning nozzles 20d, 20f according to this modification are configured such that a part of the cleaning solution Lq discharged from the cleaning nozzle 20d (the discharge port 21d) and the cleaning nozzle 20f (the discharge port 21f) and brought into contact with the bottom surface 11 of the dresser 10 moves and passes through the center C1 of the bottom surface 11 of the dresser 10.

In this modification, the same effects can be achieved similarly to the above-described embodiments.

Referring to FIG. 9, in this modification, a distance from the discharge ports 21c, 21e to the bottom surface 11 of the dresser 10 is shorter than a distance from the discharge ports 21d, 21f to the bottom surface 11 of the dresser 10. Specifically, a length of the discharge central axis XL2 of the cleaning solution Lq discharged from the discharge ports 21c, 21e is shorter than a length of the discharge central axis XL2 of the cleaning solution Lq discharged from the discharge ports 21d, 21f. Therefore, a pressure applied to the bottom surface 11 of the dresser 10 from the cleaning solution Lq discharged from the discharge ports 21c, 21e (a contact pressure) is higher than a pressure applied to the bottom surface 11 of the dresser 10 from the cleaning solution Lq discharged from the discharge ports 21d, 21f (a contact pressure).

Thus, with this modification, the cleaning solution Lq with a high contact pressure and the cleaning solution Lq with a low contact pressure can effectively clean a wide area of the bottom surface 11 of the dresser 10.

Modification 3

A polishing apparatus 1c according to Modification 3 of the embodiment is described below. The polishing apparatus 1c according to this modification differs from the above-described polishing apparatus 1a according to Modification 1 or the polishing apparatus 1b according to Modification 2 in that the polishing apparatus 1c includes cleaning nozzles 20g, 20h, 20i, 20j as a specific example of the plurality of cleaning nozzles.

FIG. 11 is a schematic plan view of the cleaning nozzles of the polishing apparatus 1c of this modification, viewed from the discharge port side. The cleaning nozzle 20g has a discharge port 21g, the cleaning nozzle 20h has a discharge port 21h, the cleaning nozzle 20i has a discharge port 21i, and the cleaning nozzle 20j has a discharge port 21j.

In FIG. 11, the discharge ports 21g, 21h, 21i, 21j are illustrated as circular shapes to simplify the illustration, but the actual shapes of the discharge ports 21g, 21h, 21i, 21j are not limited to circular shapes. For example, the discharge ports 21g, 21h, 21i, 21j may be slit or ellipse-shaped, and the shape around the discharge port may be concave such that the discharge liquid is discharged in a fan shape.

FIG. 12 is a schematic plan view of a positional relationship between the dresser 10 and the cleaning nozzles when the dresser cleaning process according to this modification is executed. Referring to FIG. 11 and FIG. 12, the plurality of cleaning nozzles 20g, 20h, 20i, 20j according to this modification are also positioned in a direction along the transverse center line CL1 in plan view.

Referring to FIG. 12, the discharge ports 21g, 21h, 21i, 21j according to this modification are positioned on the Y-direction side with respect to the transverse center line CL1 in plan view. The discharge ports 21g, 21h are positioned on the −X-direction side with respect to the longitudinal center line CL2 in plan view, and the discharge ports 21i, 21j are positioned on the X-direction side with respect to the longitudinal center line CL2 in plan view. The discharge port 21g is positioned on the Y-direction side (farther from the transverse center line CL1) with respect to the discharge port 21h, and the discharge port 21i is positioned on the Y-direction side with respect to the discharge port 21j.

The plurality of cleaning nozzles 20g, 20h, 20i, 20j according to this modification are arranged such that the cleaning solution Lq discharged from these cleaning nozzles when the dresser cleaning process is executed contacts the entire surface of the bottom surface 11 of the rotating dresser 10, or contacts a portion of the bottom surface 11 and moves over the entire surface. This allows effective cleaning of the entire surface of the bottom surface 11 of the dresser 10.

In this modification, similarly to the case of Modification 1 described above (FIG. 6), the cleaning nozzles 20g, 20h, 20i, 20j discharge the cleaning solution Lq in a fan shape about the discharge central axis XL2 and in a direction away from the polishing pad Pd in plan view. The intersection point IP where the discharge central axis XL2 intersects with the bottom surface 11 of the dresser 10 is positioned closer to the cleaning nozzles 20g, 20h, 20i, 20j than the transverse center line CL1 on the bottom surface 11 of the dresser 10 in plan view.

Among the plurality of cleaning nozzles, at least the cleaning nozzle 20h discharges the cleaning solution Lq such that a part of the cleaning solution Lq that is discharged from the discharge port 21h of the cleaning nozzle 20h and brought into contact with the bottom surface 11 of the dresser 10 moves and passes through the center C1 of the bottom surface 11 of the dresser 10.

In this modification, the same effects can be achieved similarly to the above-described embodiments.

The cleaning nozzles 20g, 20h, 20i, 20j according to this modification discharge the cleaning solution Lq such that a pressure (the contact pressure) applied from the cleaning solution Lq to the bottom surface 11 of the dresser 10 is partially higher, similarly to the cleaning nozzles 20a, 20b according to Modification 1 described in FIG. 6 and other examples.

Specifically, as illustrated in FIG. 12, the two triangular sides of the fan shaped cleaning solution Lq discharged from the discharge ports 21g, 21h, 21i, 21j according to this modification have a short side ts1 (the short side), which has a short distance from the discharge port to the bottom surface 11 of the dresser 10, and a long side ts2 (the long side), which has a long distance from the discharge port to the bottom surface 11 of the dresser 10. This configuration allows the bottom surface 11 of the dresser 10 to be effectively cleaned in this modification similarly to Modification 1.

EXAMPLE

The results of actually cleaning the bottom surface 11 of the dresser 10 using the polishing apparatus 1 according to the above-described embodiment are described below. FIG. 13 illustrates the results of cleaning the bottom surface 11 of the dresser 10 using the polishing apparatus 1 according to the embodiment. Specifically, No. 1 of FIG. 13 illustrates a photograph of the bottom surface 11 of the dresser 10 before the cleaning, and No. 2 illustrates a photograph of the bottom surface 11 of the dresser 10 after the cleaning.

As illustrated in No. 1 of FIG. 13, the bottom surface 11 of the dresser 10 before the cleaning was entirely adhered to the polishing solution (in the picture, what appears white is the polishing solution). The bottom surface 11 of the dresser 10 of No. 1 was cleaned using the polishing apparatus 1 of the embodiment. Specifically, while rotating the dresser 10 a plurality of times, the cleaning solution Lq was discharged from the cleaning nozzle 20 according to the embodiment for about 5 seconds to clean the bottom surface 11 of the dresser 10.

As a result of this cleaning, as exemplified in No. 2, the polishing solution on the bottom surface 11 of the dresser 10 was removed entirely. In other words, the entire bottom surface 11 of the dresser 10 was able to be cleaned while inhibiting the center of the entire bottom surface 11 of the dresser 10 from being insufficiently cleaned. The same results as No. 2 in FIG. 13 were obtained when the bottom surface 11 of the dresser 10 was cleaned using the polishing apparatuses from Modification 1 to Modification 3.

Although the embodiments and modifications of the present invention have been described in detail above, the present invention is not limited to such specific embodiments and modifications, and various modifications and changes are possible within the scope of the present invention as described in the claims.

REFERENCE SIGNS LIST

    • 1 . . . polishing apparatus
    • 2 . . . polishing table
    • 3 . . . top ring
    • 10 . . . dresser
    • 11 . . . bottom surface
    • 20 . . . cleaning nozzle
    • 21 . . . discharge port
    • 32 . . . dresser rotation mechanism
    • C1 . . . center
    • CL1 . . . transverse center line (“center line”)
    • IP . . . intersection point
    • Lq . . . cleaning solution
    • P1 . . . dressing position
    • P2 . . . standby position
    • pd . . . polishing pad
    • Wf . . . substrate
    • XL2 . . . discharge central axis

Claims

1. A polishing apparatus comprising:

a polishing table configured to hold a polishing pad for polishing a substrate;
a top ring configured to hold the substrate;
a dresser configured to dress the polishing pad, the dresser being movable between a dressing position in which the dresser is positioned above the polishing pad and a standby position in which the dresser is not positioned above the polishing pad;
at least one cleaning nozzle configured to discharge a cleaning solution from below the dresser to a bottom surface of the dresser to clean the bottom surface when the dresser is in the standby position; and
a dresser rotation mechanism configured to rotate the dresser during cleaning of the dresser with the cleaning solution, wherein
the at least one cleaning nozzle discharges the cleaning solution in a fan shape and in a direction away from the polishing pad,
an intersection point where a discharge central axis as a central axis of a fan shape of the discharged cleaning solution intersects with the bottom surface of the dresser is positioned closer to the at least one cleaning nozzle than the center line of the bottom surface of the dresser, and the center line is perpendicular to the discharge central axis, in a plan view, and
the at least one cleaning nozzle discharges the cleaning solution such that a part of the cleaning solution discharged from the cleaning nozzle and brought into contact with the bottom surface of the dresser moves and passes through the center of the bottom surface of the dresser.

2. The polishing apparatus according to claim 1, wherein

the at least one cleaning nozzle includes a plurality of cleaning nozzles.

3. The polishing apparatus according to claim 2, wherein

the plurality of cleaning nozzles discharge the cleaning solution such that when the cleaning solution discharged from the plurality of cleaning nozzles contacts the bottom surface of the dresser, the pressure applied to the bottom surface from the cleaning solution is partially increased.

4. The polishing apparatus according to claim 3, wherein

the plurality of cleaning nozzles are arranged such that the cleaning solution discharged from the plurality of cleaning nozzles contacts an entire surface of the bottom surface of the rotating dresser, or contacts a portion of the bottom surface of the rotating dresser and subsequently moves over the entire surface of the bottom surface.
Patent History
Publication number: 20250128380
Type: Application
Filed: Oct 23, 2024
Publication Date: Apr 24, 2025
Applicant: EBARA CORPORATION (Tokyo)
Inventor: Matsutaro MIYAMOTO (Tokyo)
Application Number: 18/923,685
Classifications
International Classification: B24B 53/017 (20120101); B24B 37/34 (20120101);