SUBSTRATE PROCESSING APPARATUS

Description

CROSS-REFERENCE TO RELATED APPLICATION

This U.S. non-provisional patent application claims priority under 35 U.S.C. § 119 from Korean Patent Application No. 10-2024-0102063, filed on Jul. 31, 2024, the entire contents of which are hereby incorporated by reference.

BACKGROUND

The present disclosure relates to a substrate processing apparatus, and more particularly, to a substrate processing apparatus with increasing durability of a polishing pad.

A semiconductor device may be manufactured through various processes. For example, the semiconductor device may be manufactured through a photo process, an etching process, a deposition process, and the like of a substrate. Before the processes, a surface of the substrate may need to be planarized. For the purpose of this, a polishing process of the substrate may be performed. The polishing process may be performed by various methods. For example, a chemical mechanical polishing (CMP) process may be used to planarize the substrate.

SUMMARY

The present disclosure provides a substrate processing apparatus with increased durability of a polishing pad.

The present disclosure also provides a substrate processing apparatus for increasing a removal rate.

A technical goal of the inventive concept is not limited to the goal(s) mentioned above, and other technical goals that are not mentioned may be clearly understood from description below by those skilled in the art.

In some embodiments of the inventive concept, a substrate processing apparatus includes a plate configured to rotate a polishing pad, a polishing head on the plate, a slurry supply unit configured to supply slurry onto the polishing pad, and a charging pad, on the polishing pad, adjacent the polishing head, wherein, when the polishing pad and the charging pad are in contact with each other, friction charging occurs between the charging pad and the polishing pad.

In some embodiments of the inventive concept, a substrate processing apparatus includes a plate configured to support a polishing pad, a polishing head on the polishing pad, an external ring structure at least partially positioned outside of the polishing head, and charging pads coupled to the external ring structure, wherein the external ring structure includes a driving unit supported by the polishing head, an external ring surrounding the outside of the polishing head, and a connection unit connecting the driving unit and the external ring, and the charging pads are circumferentially spaced apart from each other on a lower surface of the external ring.

In some embodiments of the inventive concept, a substrate processing apparatus includes a plate configured to rotate a polishing pad, a polishing head on the polishing pad, and including a polishing head body and a retainer ring, a slurry supply unit configured to supply slurry onto the polishing pad, a conditioning unit spaced apart from the polishing head, and a charging pad in contact with an upper surface of the polishing pad, wherein the charging pad is spaced apart from the retainer ring, and the charging pad includes at least one of nylon, polypropylene, and a styrene-butadiene copolymer.

BRIEF DESCRIPTION OF THE FIGURES

The accompanying drawings are included to provide a further understanding of the inventive concept, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the inventive concept and, together with the description, serve to explain principles of the inventive concept. In the drawings:

FIG. 1 is a perspective view illustrating a substrate processing apparatus according to some embodiments of the inventive concept;

FIG. 2 is a plan view illustrating a substrate processing apparatus according to some embodiments of the inventive concept;

FIG. 3 is a cross-sectional view illustrating a substrate processing apparatus according to some embodiments of the inventive concept, and is a diagram taken along line A-A′ of FIG. 2;

FIG. 4 is a fragmentary perspective view partially illustrating a substrate processing apparatus according to some embodiments of the inventive concept;

FIG. 5 is a bottom view for describing a retainer ring according to some embodiments of the inventive concept;

FIG. 6 is a cross-sectional view partially illustrating a substrate processing apparatus according to some embodiments of the inventive concept, and is a diagram taken along line B-B′ of FIG. 4;

FIGS. 7 and 8 are enlarged diagrams of region X of FIG. 6;

FIG. 9 is a fragmentary perspective view partially illustrating a substrate processing apparatus according to some embodiments of the inventive concept;

FIGS. 10 and 11 are bottom views for describing a retainer ring according to embodiments of the inventive concept;

FIG. 12 is a cross-sectional view partially illustrating a substrate processing apparatus according to some embodiments of the inventive concept, and is a diagram taken along line B-B′ of FIG. 9;

FIG. 13 is a plan view illustrating a substrate processing apparatus according to some embodiments of the inventive concept;

FIG. 14 is a cross-sectional view illustrating a substrate processing apparatus according to some embodiments of the inventive concept, and is a diagram taken along line C-C′ of FIG. 13;

FIGS. 15 to 17 are plan views illustrating a substrate processing apparatus according to embodiments of the inventive concept; and

FIGS. 18 to 21 are diagrams for describing a method for manufacturing a semiconductor device according to some embodiments of the inventive concept.

DETAILED DESCRIPTION

Hereinafter, example embodiments of the inventive concept will be described with reference to the accompanying drawings. The same reference numerals or symbols may refer to the same components throughout the entire specification.

FIG. 1 is a perspective view illustrating a substrate processing apparatus according to some embodiments of the inventive concept. FIG. 2 is a plan view illustrating a substrate processing apparatus according to some embodiments of the inventive concept. FIG. 3 is a cross-sectional view illustrating a substrate processing apparatus according to some embodiments of the inventive concept, and is a diagram taken along line A-A′ of FIG. 2.

Referring to FIGS. 1 to 3, a substrate processing apparatus 1 may be provided. The substrate processing apparatus 1 according to embodiments of the inventive concept may be a chemical mechanical polishing apparatus that polishes one surface of a substrate WF. The wording, “a substrate WF” used in the present specification may mean a silicon (Si) wafer, but embodiments of the inventive concept are not limited thereto. The substrate processing apparatus 1 may include a polishing unit 10, a polishing head 20, a slurry supply unit 30 and a conditioning unit 40.

The polishing unit 10 may include a polishing pad 11 and a plate 13. The polishing pad 11 and the plate 13 may be coupled to each other. In addition, the polishing pad 11 and the plate 13 may be separated from each other. For example, the polishing pad 11 may be separated from the plate 13 after a certain period of time, and may be substituted with a new polishing pad 11.

The polishing pad 11 of the polishing unit 10 may be located on the plate 13. For example, a lower surface of the polishing pad 11 may be in contact with an upper surface of the plate 13. The polishing pad 11 may have a circular plate shape having an upper surface parallel to a first direction D1 and a second direction D2. A rotational center or axis of the polishing pad 11 may be located on the same line as a rotational center or axis of the plate 13. The polishing pad 11 may rotate with the plate 13. For example, the polishing pad 11 may rotate around a rotational axis parallel to a third direction D3. The substrate WF may be located on the polishing pad 11. An upper surface of the polishing pad 11 and one surface of the substrate WF may be in contact with each other. As the polishing pad 11 rotates, the polishing pad 11 may polish the substrate WF. The polishing pad 11 may be divided into a plurality of regions, but embodiments of the inventive concept are not limited thereto. For example, the polishing pad 11 may include a polymer material such as polyurethane.

In the present specification, the first direction D1 and the second direction D2 may cross or intersect each other. The third direction D3 may cross or intersect the first direction D1 and the second direction D2. For example, the first direction D1, the second direction D2, and the third direction D3 may be perpendicular to each other. In the present specification, the first direction D1 and the second direction D2 may be referred to as horizontal directions, and the third direction D3 may be referred to as a vertical direction.

The plate 13 of the polishing unit 10 may be located under the polishing pad 11. The plate 13 may support the polishing pad 11 under the polishing pad 11. The plate 13 may be coupled with the polishing pad 11 to rotate the polishing pad 11. For example, the plate 13 may be rotated by a driving unit including a motor, etc. When the polishing pad 11 has a circular plate shape, the plate 13 may also have a circular plate shape, but embodiments of the inventive concept are not limited thereto. In other words, the polishing unit 10 may rotate around one rotational axis to have one rotational speed.

The polishing head 20 may be located on the polishing pad 11 of the polishing unit 10, and may support and/or rotate the substrate WF. For example, the polishing head 20 may dispose the substrate WF on the polishing pad 11 such that one surface of the substrate WF faces the polishing pad 11. The polishing head 20 may rotate independently of the polishing unit 10. A relative rotational speed of the polishing head 20 with respect to the polishing unit 10 may change over time. A relative position of the polishing head 20 with respect to the polishing unit 10 may change over time. For example, the polishing head 20 may move on the polishing pad 11 in a horizontal direction. In addition, the polishing head 20 may move up in a vertical direction from a position on which the polishing head 20 is in contact with the polishing pad 11. According to some embodiments of the inventive concept, the polishing head 20 may include a head supporting member 21, a polishing head body 23, and a retainer ring 25.

The head supporting member 21 of the polishing head 20 may be coupled with the polishing head body 23. Accordingly, the head supporting member 21 may dispose the substrate WF coupled with the polishing head body 23 at a certain position on the polishing pad 11. The head supporting member 21 may include a driving portion, and the like, and the driving portion may rotate the polishing head body 23.

The polishing head body 23 of the polishing head 20 may be located under the head supporting member 21. The polishing head body 23 may support the substrate WF. For example, the polishing head body 23 may support the substrate WF located on a lower surface thereof by using a vacuum pressure. The polishing head body 23 may include a porous structure exposed on the lower surface thereof, but embodiments of the inventive concept are not limited thereto.

The retainer ring 25 of the polishing head 20 may be located under the polishing head body 23. The retainer ring 25 may be coupled with the polishing head body 23. For example, the retainer ring 25 may be coupled to the lower surface of the polishing head body 23. The retainer ring 25 may surround the substrate WF. Accordingly, the substrate WF may be located inside the retainer ring 25 on the lower surface of the polishing head body 23.

The slurry supply unit 30 may be spaced apart from the polishing pad 11 in the vertical direction. On a plan view, the slurry supply unit 30 may be located between the polishing head 20 and the conditioning unit 40. For example, the slurry supply unit 30 may be located between a front end of the polishing head 20 and a back end of the conditioning unit 40 with respect to a rotational direction of the polishing unit 10. In addition, the slurry supply unit 30 may have a spray hole 30h thereinside. The spray hole 30h may be provided in plurality, but embodiments of the inventive concept are not limited thereto. According to some embodiments of the inventive concept, the spray hole 30h may have a slit shape extending in one direction. The slurry supply unit 30 may supply slurry onto the polishing pad 11 through the spray hole 30h. For example, the slurry supply unit 30 may supply the slurry onto an upper surface of the polishing pad 11 so as to smoothly perform a polishing process of the substrate WF.

The conditioning unit 40 may be located on the polishing pad 11 of the polishing unit 10. On a plan view, the conditioning unit 40 may be disposed spaced apart from the polishing head 20 and the slurry supply unit 30. According to some embodiments of the inventive concept, the conditioning unit 40 may include a conditioning body 41 and a conditioning pad 43. The conditioning body 41 and the conditioning pad 43 may be coupled with each other, and may be separated from each other.

The conditioning body 41 of the conditioning unit 40 may include a driving portion. The conditioning body 41 may be rotated by the driving portion including a motor, etc. Accordingly, the conditioning pad 43 may rotate with the conditioning body 41. The conditioning body 41 may rotate independently of the polishing unit 10. A relative rotational speed of the conditioning body 41 respect to the polishing unit 10 may change over time. A relative position of the conditioning body 41 respect to the polishing unit 10 may change over time. For example, the conditioning body 41 may move on the polishing pad 11 in a horizontal direction. In addition, the conditioning body 41 may move up in the vertical direction from a position on which the conditioning body 41 or the conditioning pad 43 is in contact with the polishing pad 11.

The conditioning pad 43 of the conditioning unit 40 may be located under the conditioning body. The conditioning pad 43 may be in selective contact with the polishing pad 11. When the polishing pad 11 rotates, the conditioning pad 43 may be in contact with the polishing pad 11. Accordingly, the conditioning pad 43 may partially polish the polishing pad 11. The conditioning pad 43 may change a state of an upper surface of the polishing pad 11. For example, the conditioning pad 43 may polish the polishing pad 11 to constantly maintain the state of the upper surface of the polishing pad 11. The conditioning pad 43 may include a diamond polishing pad.

FIG. 4 is a fragmentary perspective view partially illustrating a substrate processing apparatus according to some embodiments of the inventive concept. FIG. 5 is a bottom view for describing a retainer ring according to some embodiments of the inventive concept. FIG. 6 is a cross-sectional view partially illustrating a substrate processing apparatus according to some embodiments of the inventive concept, and is a diagram taken along line B-B′ of FIG. 4. FIGS. 7 and 8 are enlarged diagrams of region X of FIG. 6.

Hereinafter, for convenience of description, duplicate description of that described with reference to FIGS. 1 to 3 may be omitted, and difference(s) will be described in detail.

Referring to FIGS. 4 to 6, the retainer ring 25 of the polishing head 20 may be located between the polishing pad 11 and the polishing head body 23. The retainer ring 25 may have a central axis CA extending in the third direction D3. The retainer ring 25 may be rotatable with respect to the central axis CA. On a plan view, the retainer ring 25 may have a ring shape.

The retainer ring 25 may have an upper surface 25U and a lower surface 25L opposed to the upper surface 25U. The upper surface 25U of the retainer ring 25 may be in contact with the lower surface of the polishing head body 23. The lower surface 25L of the retainer ring 25 may be adjacent to an upper surface 11U of the polishing pad 11. In addition, the retainer ring 25 may have an inner surface or inner side surface 251 and an outer surface or outer side surface 253 opposed to the inner surface 251. The inner surface 251 of the retainer ring 25 may be adjacent to the substrate WF facing the central axis CA. An external or outer side surface of the substrate WF and the inner surface 251 of the retainer ring 25 may face each other. The outer surface 253 of the retainer ring 25 may be aligned with or coplanar with an external or outer side surface of the polishing head body 23, but embodiments of the inventive concept are not limited thereto.

The retainer ring 25 may have first grooves GV1 on or extending from the lower surface 25L thereof. Each of the first grooves GV1 may be indented from the lower surface 25L of the retainer ring 25 toward the upper surface 25U of the retainer ring 25. That is, the first grooves GV1 may have a shape in which the retainer ring 25 is partially recessed. Accordingly, each of the first grooves GV1 may have a depth along the third direction D3. A depth of each of the first grooves GV1 may be smaller than a thickness of the retainer ring 25. Each of the first grooves GV1 may extend from the inner surface 251 of the retainer ring 25 to the outer surface 253 of the retainer ring 25. Each of the first grooves GV1 may have a linear shape, but embodiments of the inventive concept is not limited thereto. The first grooves GV1 may be spaced apart from each other along a direction of the circumference of the retainer ring 25. Accordingly, the slurry present on the outer surface 253 of the retainer ring 25 may move onto the inner surface 251 of the retainer ring 25 through the first grooves GV1.

Charging pads CP may be provided, on the polishing pad 11, adjacent to the polishing head 20. More specifically, the charging pads CP may be located adjacent to the retainer ring 25. For example, the charging pads CP may be in contact with the lower surface 25L of the retainer ring 25, and may be coupled with the retainer ring 25. Accordingly, the charging pads CP may be adjacent to the polishing pad 11. The charging pads CP may be spaced apart from each other along a direction of the circumference of the retainer ring 25. For example, the charging pads CP may include at least one of nylon, polypropylene, or a styrene-butadiene copolymer.

The charging pads CP may not overlap the first grooves GV1 of the retainer ring 25. On a plan view, the charging pads CP may be spaced apart from the first grooves GV1. For example, any one of the first grooves GV1 may be located between charging pads CP adjacent each other. Any one of the charging pads CP may be located between first grooves GV1 adjacent each other. In other words, the charging pads CP and the first grooves GV1 may be alternately spaced apart from each other along the direction of the circumference of the retainer ring 25.

Referring to FIGS. 7 and 8, an adhesive layer AL may be further provided between the retainer ring 25 and the charging pad CP. The adhesive layer AL may be in contact with the retainer ring 25 and the charging pad CP between the retainer ring 25 and the charging pad CP. Accordingly, the retainer ring 25 and the charging pad CP may be coupled with each other. For example, the adhesive layer AL may include a pressure sensitive adhesive (PSA).

According to some embodiments of the inventive concept, the charging pad CP may be located on the lower surface 25L of the retainer ring 25. One surface CPs of the charging pad CP (e.g., a lower surface) facing the upper surface 11U of the polishing pad 11 may be more adjacent to the polishing pad 11 than the lower surface 25L of the retainer ring 25. For example, the one surface CPs of the charging pad CP and one surface WFs of the substrate WF (e.g., a lower surface) may be coplanar with each other, and the lower surface 25L of the retainer ring 25 may be located at a higher level than the one surface WFs of the substrate WF.

According to some embodiments of the inventive concept, the charging pad CP may be located inside the retainer ring 25. The one surface CPs of the charging pad CP facing the upper surface 11U of the polishing pad 11 may be coplanar with the lower surface 25L of the retainer ring 25. For example, the one surface WFs of the substrate WF may be located at the same level as the one surface CPs of the charging pad CP and the lower surface 25L of the retainer ring 25.

The polishing pad 11 may have slurry grooves SV on the upper surface 11U thereof. The slurry grooves SV may have a form in which the polishing pad 11 is partially recessed from the upper surface 11U of the polishing pad 11. The slurry grooves SV may be spaced apart from each other. Accordingly, the polishing pad 11 may have the upper surface 11U having a step. The upper surface 11U of the polishing pad 11 may be adjacent to the one surface WFs of the substrate WF and the one surface CPs of the charging pad CP. For example, the upper surface 11U of the polishing pad 11 may be in contact with the one surface WFs of the substrate WF and the one surface CPs of the charging pad CP. Alternatively, the upper surface 11U of the polishing pad 11 may be slightly spaced apart from the one surface WFs of the substrate WF and the one surface CPs of the charging pad CP. In this case, slurry SL may be partially located between the polishing pad 11 and the substrate WF and the polishing pad 11 and the charging pad CP. As a result, the upper surface 11U of the polishing pad 11 may be substantially in contact with the one surface WFs of the substrate WF and the one surface CPs of the charging pad CP.

The slurry SL may be provided on the polishing pad 11. The slurry SL may be located in the slurry grooves SV of the polishing pad 11. The slurry SL may flow along the slurry grooves SV. Accordingly, the slurry SL may easily move on the polishing pad 11. According to some embodiments of the inventive concept, the slurry SL may include a solution LQ and abrasive AB located in the solution LQ. The abrasive AB may be uniformly distributed in the solution LQ. For example, the solution LQ may include hydrogen peroxide (H₂O₂). The abrasive AB may include a silica (SiO₂) particle. In addition, the solution LQ may not include a ferric additive.

Referring back to FIGS. 4 to 8, as the polishing head body 23 of the polishing head 20 rotates, the retainer ring 25 may rotate together. In addition, the charging pads CP coupled with the retainer ring 25 may rotate together. As the charging pads CP rotate in a state in which the charging pads CP are in contact with the polishing pad 11, friction may occur between the charging pad CP and the polishing pad 11. Accordingly, friction charging may occur between the one surface CPs of the charging pad CP and the upper surface 11U of the polishing pad 11.

According to some embodiments of the inventive concept, the polishing pad 11 may include polyurethane. The charging pads CP may include at least one of nylon, polypropylene, or a styrene-butadiene copolymer forming the friction charging with polyurethane. Accordingly, the friction charging between the polishing pad 11 and the charging pad CP may be easily formed.

Current flowing from the one surface CPs of the charging pad CP to the upper surface 11U of the polishing pad 11 or from the upper surface 11U of the polishing pad 11 to the one surface CPs of the charging pad CP may be generated by the friction charging. An OH radical may be formed from the hydrogen peroxide (H₂O₂) included in the solution LQ of the slurry SL by the current flowing between the polishing pad 11 and the charging pad CP. The OH radical may oxidize the one surface WFs of the substrate WF as an oxidizer. Accordingly, the one surface WFs of the substrate WF may be easily polished.

The substrate processing apparatus according to embodiments of the inventive concept may form the OH radical in the slurry SL without the ferric additive by using the friction charging. Accordingly, the slurry SL may be simply constituted, and thus cost thereof may be reduced. In addition, durability of other components may be prevented from being reduced by the ferric additive. For example, the ferric additive may reduce durability of the conditioning pad 43 of the conditioning unit 40 described with reference to FIGS. 1 to 3. Accordingly, durability of the substrate processing apparatus may be increased, and cost for running the substrate processing apparatus may be reduced.

FIG. 9 is an fragmentary perspective view partially illustrating a substrate processing apparatus according to some embodiments of the inventive concept. FIGS. 10 and 11 are bottom views for describing a retainer ring according to embodiments of the inventive concept. FIG. 12 is a cross-sectional view partially illustrating a substrate processing apparatus according to some embodiments of the inventive concept, and is a diagram taken along line B-B′ of FIG. 9.

Referring to FIGS. 9 to 12, an external ring structure 27 adjacent to the polishing head 20 may be further provided. For example, the external ring structure 27 may be located on an outside of the polishing head 20. The external ring structure 27 may be coupled with the polishing head body 23 of the polishing head 20. According to some embodiments of the inventive concept, the external ring structure 27 may include a driving unit or driver 271, an external ring 273 and a connection unit or connector 275.

The driving unit 271 of the external ring structure 27 may be located on the upper surface of the polishing head body 23, but embodiments of the inventive concept are not limited thereto. A portion of the driving unit 271 may be connected to and coupled with the polishing head body 23. The remaining portion of the driving unit 271 may be coupled with the connection unit 275. The driving unit 271 may move the connection unit 275 along the third direction D3. The driving unit 271 may be provided in plurality. For example, the driving unit 271 may include a motor, an actuator, etc.

The connection unit 275 of the external ring structure 27 may be located between the driving unit 271 and the external ring 273. The connection unit 275 may be located on a side surface of the polishing head body 23. The connection unit 275 may have a cylindrical or elongated shape extending along the third direction D3. One end portion of the connection unit 275 may be connected to the driving unit 271. The other end portion of the connection unit 275 may be connected to the external ring 273. For example, the connection unit 275 may connect and couple the driving unit 271 and the external ring 273. Since the connection unit 275 is moved by the driving unit 271 along the third direction D3, a height of the external ring 273 may be changed. Like the driving unit 271, the connection unit 275 may be provided in plurality.

The external ring 273 of the external ring structure 27 may be located under the connection unit 275. An upper surface 273U of the external ring 273 may be coupled with the connection unit 275. The external ring 273 may be adjacent to the polishing pad 11. The external ring 273 may surround an outside or outer side surface of the polishing head 20. On a plan view, the external ring 273 may surround the retainer ring 25. The external ring 273 may have the same central axis CA as the retainer ring 25. The external ring 273 may be rotatable with respect to the central axis CA. The external ring 273 may be located on an outer surface or outer side surface 253 of the retainer ring 25. The external ring 273 may be spaced apart from the retainer ring 25. On a plan view, the external ring 273 may have a shape of a ring having a greater diameter than the retainer ring 25.

The charging pads CP may be located under the external ring 273. The charging pads CP may be coupled to a lower surface 273L of the external ring 273. The adhesive layer AL described with reference to FIGS. 7 and 8 may be provided between the charging pads CP and the lower surface 273L of the external ring 273. The charging pads CP may be located on the polishing pad 11. The height of the external ring 273 may change due to the driving unit 271, and thus heights of the charging pads CP may change. Accordingly, the charging pads CP may be substantially in contact with the upper surface 11U of the polishing pad 11. Accordingly, as described with reference to FIGS. 4 to 8, friction charging may occur between the polishing pad 11 and the charging pads CP.

The charging pads CP may be spaced apart from each other along a direction of the circumference of the external ring 273. Since each of the charging pads CP may have a constant thickness or width, a space may be formed between the charging pads CP adjacent to each other. The space between the charging pads CP adjacent to each other may be present on the lower surface 273L of the external ring 273. For example, the external ring 273 may have, on the lower surface 273L thereof, a second groove GV2, which is the space between the charging pads CP adjacent to each other. The second groove GV2 may be located on the lower surface 273L of the external ring 273 between the charging pads CP. The second groove GV2 may be provided in plurality, and the plurality of second grooves GV2 may be spaced apart from each other along a direction of the circumference of the external ring 273.

According to some embodiments of the inventive concept, the first groove GV1 of the retainer ring 25 may have or be orientated in a first central direction CD1 toward the central axis CA. The second groove GV2 of the external ring 273 adjacent to the first groove GV1 may have or be orientated in a second central direction CD2 toward the central axis CA. For example, the first central direction CD1 of the first groove GV1 toward the central axis CA and the second central direction CD2 of the second groove GV2 toward the central axis CA may be the same as each other. The first and second grooves GV1 and GV2 adjacent to each other may overlap each other toward the central axis CA. For example, the first and second grooves GV1 and GV2 adjacent to each other may be radially aligned. Accordingly, the slurry may easily flow to the substrate WF through the first and second grooves GV1 and GV2. Accordingly, a large amount of the slurry may be provided onto the one surface WFs of the substrate WF.

According to some embodiments of the inventive concept, the first groove GV1 of the retainer ring 25 may have or be orientated in the first central direction CD1 toward the central axis CA, and the second groove GV2 of the external ring 273 may have or be orientated in the second central direction CD2 toward the central axis CA. For example, the first central direction CD1 of the first groove GV1 toward the central axis CA and the second central direction CD2 of the second groove GV2 toward the central axis CA may be different from each other. The first and second grooves GV1 and GV2 may not overlap each other toward the central axis CA, and may be spaced apart from each other. Accordingly, it may be difficult for the slurry to flow to the substrate WF through the first and second grooves GV1 and GV2. Accordingly, a small amount of the slurry may be provided onto the one surface WFs of the substrate WF.

The substrate processing apparatus according to embodiments of the inventive concept may further include the external ring structure 27 coupled with the charging pads CP. The external ring structure 27 may control the heights of the charging pads CP. The charging pads CP may be worn due to friction between the polishing pad 11 and the charging pads CP. The external ring structure 27 may control the heights of the charging pads CP to constantly maintain a distance between the polishing pad 11 and the charging pads CP. That is, the charging pads CP may be substantially in contact with the polishing pad 11 regardless of wearing of the charging pads CP. As a result, the friction charging between the polishing pad 11 and the charging pads CP may be continuously formed. Accordingly, lifespan of the charging pads CP may be increased. Accordingly, durability of the substrate processing apparatus may be increased.

FIG. 13 is a plan view illustrating a substrate processing apparatus according to some embodiments of the inventive concept. FIG. 14 is a cross-sectional view illustrating a substrate processing apparatus according to some embodiments of the inventive concept, and is a diagram taken along line C-C′ of FIG. 13. FIGS. 15 to 17 are plan views illustrating a substrate processing apparatus according to embodiments of the inventive concept.

Referring to FIGS. 13 and 14, the substrate processing apparatus 1 may further include a charging unit 50. The charging unit 50 may be located on the polishing pad 11 of the polishing unit 10. The charging unit 50 may be spaced apart from the conditioning unit 40. On a plan view, the charging unit 50 may be located between the polishing head 20 and the slurry supply unit 30. For example, the charging unit 50 may be located on a front end of the polishing head 20 with respect to a rotational direction of the polishing unit 10. The charging unit 50 may be located on a back end of the slurry supply unit 30 with respect to a rotational direction of the polishing unit 10. Accordingly, the slurry discharged from the slurry supply unit 30 may pass under the charging unit 50 to flow toward the polishing head 20.

The charging unit 50 may include a charging unit body 51 and the charging pad CP coupled to a lower surface of the charging unit body 51. For example, the charging unit body 51 may have a shape of a circular plate. In this case, the charging unit body 51 may include a driving portion. The charging unit body 51 and the charging pad CP may rotate together by the driving portion of the charging unit body 51. In addition, the charging unit body 51 may move on the polishing pad 11 in a horizonal direction and a vertical direction.

The charging pad CP may be located between the polishing pad 11 and the charging unit body 51. When the charging unit body 51 has a shape of a circular plate, the charging pad CP may also have the shape of a circular plate. The charging pad CP may be substantially in contact with the upper surface 11U of the polishing pad 11. The charging pad CP may be substantially the same as the charging pad CP described with reference to FIGS. 4 to 8. That is, friction charging may occur between the charging pad CP and the polishing pad 11, and the slurry including the OH radical may be formed due to the friction charging.

Referring to FIG. 15, the charging unit body 51 of the charging unit 50 may have a form extending in one direction. On a plan view, the charging unit body 51 may have a shape of a bar or elongated member. The charging unit body 51 may include a robot arm on one end away from the center of the polishing unit 10. The charging unit body 51 may perform repeatedly moving left and right by the robot arm.

The charging pad CP of the charging unit 50 may be partially coupled with a lower surface of the charging unit body 51. Like the charging unit body 51, the charging pad CP may have a form extending in one direction (e.g., elongated).

Referring to FIG. 16, the charging unit body 51 of the charging unit 50 may include a part having a shape of an arch and a part having a shape of a bar extending in one direction. On a plan view, the charging unit body 51 may have a shape of a hook. The charging unit body 51 may include a straight portion and a curved portion. The charging unit body 51 may include the robot arm, and may perform repeatedly moving in a horizontal direction by the robot arm.

The charging pad CP of the charging unit 50 may be partially coupled with the lower surface of the charging unit body 51. On a plan view, the charging pad CP may overlap the part having a shape of an arch of the charging unit body 51. That is, the charging pad CP may have a shape of an arch or be curved. Accordingly, when the slurry passes through the charging pad CP, a moving path of the slurry may change. Accordingly, the slurry may be efficiently supplied onto the substrate WF in the polishing head 20.

Referring to FIG. 17, the charging unit 50 may be located on one side surface of the slurry supply unit 30. The charging unit 50 may have a form extending in one direction, and may be coupled to the one side surface of the slurry supply unit 30. In this case, the charging unit 50 may not include a separate driving portion. For example, the charging unit 50 may be coupled to a side surface corresponding to the back end of the slurry supply unit 30 with respect to a rotational direction of the polishing unit 10. Accordingly, the slurry discharged from the slurry supply unit 30 may immediately pass under the charging unit 50.

Referring back to FIGS. 13 to 17, the charging pad CP of the charging unit 50 may be located between the slurry supply unit 30 and the polishing head 20. More specifically, the charging pad CP may be located between a front end of the polishing head 20 and a back end of the slurry supply unit 30 with respect to a rotational direction of the polishing unit 10. That is, the charging pad CP may be located on a moving path of the slurry from the slurry supply unit 30 toward the polishing head 20. Accordingly, the slurry including the OH radical formed by the friction charging between the charging pad CP and the polishing pad 11 may be supplied onto the substrate WF in the polishing head 20.

The substrate processing apparatus 1 according to embodiments of the inventive concept may include the charging pad CP located adjacent to the polishing head 20. For example, the charging pad CP may be located on the moving path of the slurry flowing onto one surface of the substrate WF in the polishing head 20. The polishing pad 11 may rotate in a state in which the polishing pad 11 is substantially in contact with the charging pad CP, and thus friction may occur therebetween. Accordingly, the friction charging may occur due to the friction between the polishing pad 11 and the charging pad CP. The friction charging may form the OH radical from the hydrogen peroxide (H₂O₂) included in the slurry. The OH radical may oxidize one surface of the substrate WF. Accordingly, a semiconductor process of polishing the substrate WF may be easily performed.

FIGS. 18 to 21 are diagrams for describing a method for manufacturing a semiconductor device according to some embodiments of the inventive concept.

Referring to FIG. 18, the substrate WF may be provided. The substrate WF may be a semiconductor substrate including silicon (Si), germanium (Ge), silicon-germanium (SiGe) or the like, or a compound semiconductor substrate. For example, the substrate WF may be a silicon (Si) substrate.

An insulating film 110 may be formed on the substrate WF. The insulating film 110 may be formed in a deposition process. For example, the deposition process may include a chemical vapor deposition (CVD) process, a physical vapor deposition (PVD) process, and an atomic layer deposition (ALD) process. The insulating film 110 may have a constant thickness on the substrate WF, and may have a flat upper surface 110U.

Thereafter, a trench TR penetrating the insulating film 110 may be formed. An operation of forming the trench TR may include an operation of forming a mask pattern on the insulating film 110, an operation of etching the insulating film 110 by using the mask pattern, and an operation of removing the mask pattern. The operation of etching the insulating film 110 may include an operation of partially exposing an upper surface of the substrate WF. That is, the substrate WF may be partially exposed by the trench TR. For example, the insulating film 110 may include at least one of silicon oxide, silicon nitride, or silicon oxynitride, but embodiments of the inventive concept are not limited thereto.

Referring to FIG. 19, a metal film ML may be formed on a front surface of the substrate WF. The metal film ML may be formed in a deposition process or a damascene process. The metal film ML may fill the inside of the trench TR, and may cover the upper surface 110U of the insulating film 110. Accordingly, the metal film ML may have an upper surface MLU having a higher vertical level than the upper surface 110U of the insulating film 110. For example, the metal film ML may include tungsten (W).

Thereafter, a chemical mechanical polishing process may be performed with respect to the metal film ML. The chemical mechanical polishing process may be performed by the substrate processing apparatus 1 described with reference to FIGS. 1 to 17. For example, the polishing pad 11 may be located on the upper surface MLU of the metal film ML. The slurry SL including the solution LQ and the abrasive AB may be provided between the upper surface MLU of the metal film ML and the upper surface 11U of the polishing pad 11.

The substrate processing apparatus 1 described with reference to FIGS. 1 to 17 may provide the slurry SL including the OH radical formed by using the friction charging onto the one surface of the substrate WF (for example, the upper surface MLU of the metal film ML). The OH radical may oxidize the upper surface MLU of the metal film ML. Accordingly, the metal film ML may be partially oxidized. The metal film ML may include a first part MLa not oxidized, and a second part MLb oxidized by the OH radical. The second part MLb may be located on the first part MLa, and may be adjacent to the upper surface MLU of the metal film ML. The second part MLb may have a lower hardness than the first part MLa. For example, the first part MLa of the metal film ML may include tungsten (W), and the second part MLb of the metal film ML may include tungsten oxide (WO₃).

Referring to FIG. 20, the polishing pad 11 may rotate in a state in which the upper surface 11U of the polishing pad 11 and the upper surface MLU of the metal film ML are substantially in contact with each other. The abrasive AB of the slurry SL may remove the second part MLb of the metal film ML having a relatively lower hardness by rotating the polishing pad 11. The abrasive AB of the slurry SL may not remove the first part MLa of the metal film ML having a relatively higher hardness. Accordingly, the second part MLb of the metal film ML may be completely removed, and the upper surface MLU of the metal film ML may be lowered.

Thereafter, an operation of oxidizing the metal film ML and an operation of removing the oxidized metal film ML may be repeatedly performed. Accordingly, the upper surface MLU of the metal film ML may be continuously lowered.

Referring to FIG. 21, the chemical mechanical polishing process may be continuously performed until the upper surface 110U of the insulating film 110 is exposed. The metal film ML may be partially removed to form a metal pattern MP from the metal film ML. The metal pattern MP may have an upper surface MPU located on the same plane as the upper surface 110U of the insulating film 110. For example, the metal pattern MP may fill the trench TR, but may not cover the upper surface 110U of the insulating film 110. According to embodiments of the inventive concept, the metal pattern MP may function as a contact connecting different components and/or a via connecting lines in a vertical direction in the semiconductor device.

A substrate processing apparatus according to embodiments of the inventive concept may include a charging pad adjacent to a polishing head, and in contact with a polishing pad. Friction charging may occur due to friction between the polishing pad and the charging pad. An OH radical may be formed from hydrogen peroxide of slurry by using the friction charging. The OH radical may oxidize one surface of a substrate to easily polish the substrate.

In other words, since the OH radical is formed in the slurry without a ferric additive, the slurry may be simply constituted, and cost thereof may be reduced. In addition, durability of other components may be prevented from being reduced by the ferric additive. Accordingly, durability of the substrate processing apparatus may be increased, and cost for running the substrate processing apparatus may be reduced.

Although example embodiments of the present inventive concept have been described, it is understood that the present inventive concept should not be limited to these embodiments but various changes and modifications can be made by one ordinary skilled in the art within the scope of the present inventive concept as hereinafter claimed.