JP2021030409A - Elastic film, and substrate holding device - Google Patents

Abstract

To provide an elastic film capable of being easily attached to a head body of a substrate holding device while suppressing variation in a degree of deformation of the elastic film in the circumferential direction.SOLUTION: An elastic film 10 according to the present invention is used for a substrate holding device 1. The elastic film 10 comprises: a contact part 11 that contacts a substrate W and presses the substrate W against a polishing pad 19; and an edge peripheral wall 33 that extends from a peripheral end part of the contact part 11. The edge peripheral wall 33 has an edge peripheral wall lip part 33b sandwiched between a head main body 2 of the substrate holding device 1 and an edge mounting member 47 for fixing the edge peripheral wall 33 to the head main body 2. At least a part of a surface of the edge peripheral wall lip part 33b is roughened.SELECTED DRAWING: Figure 5

Description

The present invention relates to an elastic film used in a substrate holding device of a polishing device. Furthermore, the present invention relates to a substrate holding device provided with an elastic film.

The polishing apparatus for performing CMP includes a polishing table for supporting the polishing pad and a substrate holding apparatus for holding a substrate such as a wafer. The substrate holding device is sometimes referred to as a top ring or a polishing head. When polishing a substrate using such a polishing device, the substrate is held by the substrate holding device and the substrate is pressed against the polished surface of the polishing pad with a predetermined pressure. At this time, by moving the polishing table and the substrate holding device relative to each other, the substrate is in sliding contact with the polished surface, and the surface of the substrate is polished.

If the relative pressing force between the substrate being polished and the polishing surface of the polishing pad is not uniform over the entire surface of the substrate, insufficient polishing or overpolishing may occur depending on the pressing force applied to each part of the substrate. It will occur. Therefore, in order to make the pressing force on the substrate uniform, a pressure chamber formed of a flexible elastic membrane (membrane) is provided under the substrate holding device, and a fluid such as air is supplied to the pressure chamber to provide an elastic film. The substrate is pressed against the polished surface of the polishing pad by fluid pressure via the above.

Such a substrate holding device includes, for example, a head body for pressing the substrate against the polishing surface of the polishing pad, the elastic film attached to the head body, and a mounting member for fixing the elastic film to the head body. It is provided with a retainer ring that surrounds the substrate held by the head body via an elastic film. When the elastic film is fixed to the head body via the mounting member, the elastic film forms at least one pressure chamber. Such elastic membranes are consumables and require regular maintenance and / or replacement. Therefore, the elastic membrane is configured to be removable from the head body via the mounting member.

U.S. Pat. No. 8,808,062 U.S. Pat. No. 9,452,505 U.S. Pat. No. 4,544,413

However, elastic membranes are generally made of materials such as rubber that are not only flexible but also highly adhesive. Therefore, when the operator fixes the elastic film to the head body via the mounting member, a part of the elastic film is in close contact with the head body and / or the mounting member, and the elastic film is appropriately fixed to the head body. Can be difficult. More specifically, when a part (or a plurality of parts) of the elastic film is in close contact with the head body and / or the mounting member, this contacted part pulls the other part of the elastic film, and the elastic film is in the circumferential direction. There is a risk of variation in the degree of deformation. In other words, the elastic film attached to the head body may be distorted unevenly in the circumferential direction.

When polishing the substrate, a fluid having a predetermined pressure is supplied to the pressure chamber formed by the elastic film. Therefore, if the degree of deformation of the elastic film in the circumferential direction varies, the elastic film does not expand uniformly in the circumferential direction, and as a result, the uniformity of the polishing rate in the circumferential direction of the substrate may deteriorate. ..

In order to prevent the above-mentioned problems, if an operator who fixes the elastic film to the head body tries to eliminate the variation in the degree of deformation of the elastic film in the circumferential direction, the burden and labor of the operator increases, and further, the elasticity It takes a long time to fix the film to the head body.

Therefore, an object of the present invention is to provide an elastic film that can be easily attached to the head body of the substrate holding device while suppressing variation in the degree of deformation of the elastic film in the circumferential direction. Another object of the present invention is to provide a substrate holding device provided with such an elastic film.

In one aspect, it is an elastic film used for a substrate holding device, and includes a contact portion that abuts on the substrate and presses the substrate against the polishing pad, and an edge peripheral wall extending from the peripheral end portion of the contact portion. The edge peripheral wall has an edge peripheral wall lip portion sandwiched between a head main body of the substrate holding device and an edge mounting member for fixing the edge peripheral wall to the head main body. The portion is provided with an elastic membrane characterized in that at least a portion of its surface is roughened.

In one aspect, the edge peripheral wall has an edge peripheral wall main body extending from the contact portion and connected to the edge peripheral wall lip portion, and the contact surface of the edge peripheral wall main body with the edge mounting member is also rough. It has been surfaced.
In one aspect, the elastic film is disposed radially inside the edge peripheral wall and further comprises at least one internal peripheral wall extending from the abutting portion, wherein the internal peripheral wall includes the head body and the internal peripheral wall. It has an internal peripheral wall lip portion sandwiched between an internal mounting member for fixing to the head body, and at least a part of the surface of the internal peripheral wall lip portion is roughened.
In one aspect, the internal peripheral wall has an internal peripheral wall main body extending from the contact portion and connected to the internal peripheral wall lip portion, and the contact surface of the internal peripheral wall main body with the internal mounting member is also rough. It has been surfaced.
In one aspect, the entire surface of the elastic membrane is roughened.

In one aspect, an elastic film forming at least one pressure chamber for pressing the substrate, a head body to which the elastic film is fixed, and at least one mounting member for fixing the elastic film to the head body. The elastic film includes a contact portion that abuts against the substrate and presses the substrate against the polishing pad, and an edge peripheral wall extending from the peripheral end portion of the contact portion. The head body has an edge peripheral wall lip portion sandwiched between the head main body and an edge mounting member which is one of the mounting members, and at least a part of the surface of the edge peripheral wall lip portion is roughened. A substrate holding device is provided.
In one aspect, the surface of the edge mounting member is covered with a friction reducing film.

In one aspect, an elastic film forming at least one pressure chamber for pressing the substrate, a head body to which the elastic film is fixed, and at least one mounting member for fixing the elastic film to the head body. The elastic film includes a contact portion that abuts against the substrate and presses the substrate against the polishing pad, and an edge peripheral wall extending from the peripheral end portion of the contact portion. The head body has an edge peripheral wall lip portion sandwiched between the head main body and an edge mounting member which is one of the mounting members, and the surface and / or the edge mounting member facing the edge peripheral wall lip portion. Provided is a substrate holding device characterized in that the surface of the head body is roughened.

According to the present invention, the contact area of the edge peripheral wall lip portion with the edge mounting member and / or the head main body of the edge peripheral wall lip portion is compared with the case where the surface of the edge peripheral wall lip portion is not roughened. The contact area with is reduced. As a result, the elastic film is prevented from coming into close contact with the edge mounting member and / or the head body. Therefore, since the elastic film can be smoothly and easily moved with respect to the edge mounting member and / or the head body, the elastic film can be easily transferred to the head body while suppressing variation in the degree of deformation of the elastic film in the circumferential direction. Can be fixed.

FIG. 1 is a schematic view showing a polishing apparatus according to an embodiment. FIG. 2 is a schematic cross-sectional view of the substrate holding device according to the embodiment. FIG. 3 is an enlarged cross-sectional view showing a part of the elastic film shown in FIG. FIG. 4 is an enlarged cross-sectional view of the vicinity of the second mounting ring shown in FIG. FIG. 5 is a diagram showing a roughened surface of the edge peripheral wall lip portion of the elastic film. FIG. 6 is a diagram illustrating the roughened surface of the elastic membrane according to another embodiment. FIG. 7 is a diagram illustrating the roughened surface of the elastic membrane according to still another embodiment. FIG. 8 is a diagram illustrating the roughened surface of the elastic membrane according to still another embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing a polishing apparatus according to an embodiment. As shown in FIG. 1, the polishing apparatus includes a polishing table 18 that supports the polishing pad 19, and a substrate holding device 1 that holds a wafer W as an example of a substrate and presses it against the polishing pad 19 on the polishing table 18. In the following description, the substrate holding device 1 is referred to as a "polishing head 1".

The polishing table 18 is connected to a table motor 29 arranged below the table shaft 18a via a table shaft 18a, and is rotatable around the table shaft 18a. The polishing pad 19 is attached to the upper surface of the polishing table 18, and the surface 19a of the polishing pad 19 constitutes a polishing surface for polishing the wafer W. A polishing liquid supply nozzle 25 is installed above the polishing table 18, and the polishing liquid Q is supplied onto the polishing pad 19 on the polishing table 18 by the polishing liquid supply nozzle 25.

The polishing head 1 includes a head body 2 that presses the wafer W against the polishing surface 19a, and a retainer ring 3 that holds the wafer W and prevents the wafer W from popping out of the polishing head 1. The polishing head 1 is connected to a head shaft 27, and the head shaft 27 moves up and down with respect to the head arm 64 by a vertical movement mechanism 81. The vertical movement of the head shaft 27 raises and lowers the entire polishing head 1 with respect to the head arm 64 for positioning. A rotary joint 82 is attached to the upper end of the head shaft 27.

The vertical movement mechanism 81 that moves the head shaft 27 and the polishing head 1 up and down is supported by a bridge 84 that rotatably supports the head shaft 27 via a bearing 83, a ball screw 88 attached to the bridge 84, and a support column 86. The support base 85 is provided, and the servomotor 90 provided on the support base 85 is provided. The support base 85 that supports the servomotor 90 is fixed to the head arm 64 via the support column 86.

The ball screw 88 includes a screw shaft 88a connected to the servomotor 90 and a nut 88b into which the screw shaft 88a is screwed. The head shaft 27 moves up and down integrally with the bridge 84. Therefore, when the servomotor 90 is driven, the bridge 84 moves up and down via the ball screw 88, which causes the head shaft 27 and the polishing head 1 to move up and down.

The head shaft 27 is connected to the rotary cylinder 66 via a key (not shown). The rotary cylinder 66 is provided with a timing pulley 67 on the outer peripheral portion thereof. A head motor 68 is fixed to the head arm 64, and the timing pulley 67 is connected to a timing pulley 70 provided on the head motor 68 via a timing belt 69. Therefore, by rotationally driving the head motor 68, the rotary cylinder 66 and the head shaft 27 rotate integrally via the timing pulley 70, the timing belt 69, and the timing pulley 67, and the polishing head 1 rotates. The head arm 64 is supported by an arm shaft 80 rotatably supported by a frame (not shown). The polishing device includes a control device 40 that controls each device in the device, including the head motor 68 and the servo motor 90.

The polishing head 1 is configured to hold the wafer W on its lower surface. The head arm 64 is configured to be rotatable around the arm shaft 80, and the polishing head 1 holding the wafer W on the lower surface moves from the receiving position of the wafer W to the upper position of the polishing table 18 by the rotation of the head arm 64. Will be done.

Polishing of the wafer W is performed as follows. The polishing head 1 and the polishing table 18 are rotated, respectively, and the polishing liquid Q is supplied onto the polishing pad 19 from the polishing liquid supply nozzle 25 provided above the polishing table 18. In this state, the polishing head 1 is lowered to a predetermined position (predetermined height), and the wafer W is pressed against the polishing surface 19a of the polishing pad 19 at this predetermined position. The wafer W is slidably contacted with the polishing surface 19a of the polishing pad 19, whereby the surface of the wafer W is polished.

Next, an example of the configuration of the polishing head 1 will be described with reference to FIG. FIG. 2 is a schematic cross-sectional view of the polishing head (board holding device) 1 according to the embodiment. As shown in FIG. 2, the polishing head 1 includes a head body 2 that presses the wafer W against the polishing surface 19a (see FIG. 1), and a retainer ring 3 arranged so as to surround the wafer W. .. The retainer ring 3 is connected to the head main body 2, and the head main body 2 and the retainer ring 3 are configured to rotate integrally by the rotation of the head shaft 27. Further, the head body 2 and the retainer ring 3 are configured to move up and down integrally with the head shaft 27 by operating the vertical movement mechanism 81 (see FIG. 1). The head body 2 is made of, for example, a resin such as engineering plastic (for example, PEEK).

The retainer ring 3 is arranged so as to surround the elastic film 10 fixed to the head main body 2 and the wafer W held by the head main body 2 via the elastic film 10. The retainer ring 3 holds the wafer W so that the wafer W does not protrude from the polishing head 1 during polishing of the wafer W.

An elastic film 10 that comes into contact with the back surface of the wafer W (that is, the surface opposite to the surface to be polished) is fixed to the lower surface of the head body 2. The lower surface of the elastic film 10 constitutes the substrate holding surface 10a. The elastic membrane 10 has a plurality of (four in FIG. 2) annular peripheral walls 30, 31, 32, 33, and these peripheral walls 30 to 33 are arranged concentrically.

In the present embodiment, the polishing head 1 includes two mounting members 45 and 47 that fix the elastic film 10 to the head body 2. The two mounting members 45 and 47 are mounting rings having a substantially annular shape, respectively. In the following description, the mounting member 45 may be referred to as a "first mounting ring 45", and the mounting member 47 may be referred to as a "first mounting ring 45". 2 Mounting ring 47 ”.

The upper ends of the peripheral walls 30 to 33 are fixed to the lower surface of the head body 2 via two mounting rings 45 and 47. More specifically, the first mounting ring 45 fixes the upper ends of the peripheral walls 30 and 31 to the lower surface of the head body 2, and the second mounting ring 47 fixes the upper ends of the peripheral walls 32 and 33 to the lower surface of the head body 2. Will be done. These mounting rings 45 and 47 are detachably fixed to the head body 2 by fasteners (not shown) such as screws, respectively. Therefore, when the fastener is released, the mounting rings 45 and 47 are separated from the head body 2, whereby the elastic film 10 can be removed from the head body 2.

The peripheral walls 30 to 33 provide four pressure chambers between the elastic membrane 10 and the head body 2, that is, a circular central pressure chamber 16a located at the center, an annular edge pressure chamber 16d located at the outermost periphery, and a center. Intermediate pressure chambers 16b and 16c located between the pressure chamber 16a and the edge pressure chamber 16d are formed.

These pressure chambers 16a to 16d are connected to the pressure adjusting device 65 via a rotary joint 82, and a fluid (for example, air) passes through a fluid line 73 extending from the pressure adjusting device 65 to each of the pressure chambers 16a to 16d. ) Is being supplied. The pressure adjusting device 65 is connected to the control device 40, and can independently adjust the pressure in these four pressure chambers 16a to 16d.

Further, the pressure adjusting device 65 can also form a negative pressure in the pressure chambers 16a to 16d. In this way, in the polishing head 1, the pressing force applied to the wafer W is adjusted by adjusting the pressure of the fluid supplied to the pressure chambers 16a to 16d formed between the head body 2 and the elastic film 10. It can be adjusted for each area of the wafer W.

The elastic film 10 is formed of a flexible rubber material having excellent strength and durability, such as ethylene propylene rubber (EPDM), polyurethane rubber, and silicon rubber. Such an elastic film 10 has not only flexibility but also high adhesiveness. The pressure chambers 16a to 16d are also connected to an air opening mechanism (not shown), and the pressure chambers 16a to 16d can be opened to the atmosphere.

Next, the elastic film 10 shown in FIG. 2 will be described in more detail. FIG. 3 is an enlarged cross-sectional view showing a part of the elastic film 10 shown in FIG. More specifically, FIG. 3 shows a schematic cross section of half of the elastic membrane 10 divided by the vertical plane including the central axis CL of the elastic membrane 10. FIG. 4 is an enlarged cross-sectional view of the vicinity of the second mounting ring 47 shown in FIG. 2 (that is, the vicinity of the edge peripheral wall described later).

The elastic film 10 shown in FIG. 3 has a circular contact portion 11 that contacts the back surface of the wafer W, and four annular peripheral walls 30 to 33 that are connected to the contact portion 11. The contact portion 11 contacts the back surface of the wafer W and presses the wafer W against the polishing pad 19. That is, the lower surface of the contact portion 11 functions as the substrate holding surface 10a. The annular peripheral walls 30 to 33 extend upward from the upper surface of the contact portion 11.

The peripheral wall 33 is the outermost peripheral wall and extends upward from the peripheral end portion of the contact portion 11. In the present specification, the peripheral wall 33 is referred to as "edge peripheral wall 33". Further, in the present specification, the peripheral wall arranged radially inside the edge peripheral wall 33 is referred to as an internal peripheral wall. In the example shown in FIG. 3, three peripheral walls 30, 31, and 32 are configured as internal peripheral walls. In the following description, the peripheral wall 30 may be referred to as a "first internal peripheral wall 30", the peripheral wall 31 may be referred to as a "second internal peripheral wall 31", and the peripheral wall 32 may be referred to as a "third internal peripheral wall 32". There is. The number of internal peripheral walls is not limited to the illustrated example. For example, the elastic film 10 may have an edge peripheral wall 33 and one internal peripheral wall, or may have an edge peripheral wall 33 and two or more internal peripheral walls. Alternatively, the elastic film 10 may have only the edge peripheral wall 33 without having an internal peripheral wall.

The edge peripheral wall 33 has an edge peripheral wall main body 33a extending from the contact portion 11 and an edge peripheral wall lip portion 33b connected to the edge peripheral wall main body 33a. In the example shown in FIG. 3, the edge peripheral wall main body 33a extends vertically upward from the contact portion 11, and the edge peripheral wall lip portion 33b extends horizontally from the tip of the edge peripheral wall main body 33a. The edge peripheral wall main body 33a extends in an annular shape (that is, over the entire circumference of the contact portion 11) around the central axis CL, and the edge peripheral wall lip portion 33b is formed in a flange shape over the entire circumference of the edge peripheral wall main body 33a. .. The edge peripheral wall lip portion 33b has a seal protrusion 33c on its lower surface. The seal protrusion 33c is formed on the lower surface of the tip end portion of the edge peripheral wall lip portion 33b, and is formed in an annular shape over the entire circumference of the edge peripheral wall lip portion 33b.

Further, the edge peripheral wall 33 may have a flap 33d extending from a connection point between the edge peripheral wall main body 33a and the edge peripheral wall lip portion 33b. The flap 33d extends over the entire circumference of the edge peripheral wall 33. The flap 33d has a flap body 145 having an inverted U-shaped cross section and a flap lip portion 146 extending horizontally from the tip of the flap body 145. The flap lip portion 146 is sandwiched between the head body 2 and the retainer ring 3 (see FIG. 4).

As shown in FIG. 4, the edge peripheral wall lip portion 33b is a part of the edge peripheral wall 33 sandwiched between the second mounting ring 47 and the head body 2. Therefore, the edge peripheral wall lip portion 33b is formed on the upper portion of the edge peripheral wall 33 excluding the flap 33d. In other words, the edge peripheral wall lip portion 33b is connected to the upper end of the edge peripheral wall main body 33a. When the edge peripheral wall lip portion 33b is sandwiched between the head body 2 and the second mounting ring 47 and the second mounting ring 47 is fixed to the head body 2 with a fastener (not shown) such as a screw, the edge peripheral wall 33 becomes It is fixed to the head body 2. Therefore, the second mounting ring 47 functions as an edge mounting member for fixing the edge peripheral wall 33 to the head body 10.

The second mounting ring 47 is formed with a seal recess 55 into which the seal protrusion 33c is fitted. The seal recess 55 corresponds to the seal protrusion 33c and is formed over the entire circumference of the second mounting ring 47. When the edge peripheral wall 33 is attached to the head body 2, the seal protrusion 33c is fitted into the seal recess 55. In this state, when the second mounting ring 47 is attached to the head body 2 using a fastener (not shown), the seal protrusion 33c is pressed against the seal recess 55, whereby the second mounting ring 47 and the edge peripheral wall lip are pressed. The gap between the portion 33b and the portion 33b is sealed.

The third inner peripheral wall 32 also has a third inner peripheral wall main body 32a extending from the contact portion 11 and a third inner peripheral wall lip portion 32b connected to the third inner peripheral wall main body 32a. The third inner peripheral wall main body 32a also extends in an annular shape around the central axis CL, and the third inner peripheral wall lip portion 32b is formed in a flange shape over the entire circumference of the third inner peripheral wall main body 32a. The third inner peripheral wall main body 32a is connected to an inclined portion 130 extending diagonally upward in the radial direction from the contact portion 11 and an inclined portion 130, and is connected to a horizontal portion 131 extending inward in the radial direction and a horizontal portion 131. It is composed of a vertical portion 132 extending vertically from the horizontal portion 131. The third inner peripheral wall lip portion 32b is connected to the tip of the vertical portion 132 of the third inner peripheral wall main body 32a, and extends horizontally outward from the tip in the radial direction. The third inner peripheral wall 32 also has a seal protrusion 32c formed in an annular shape around the entire circumference of the third inner peripheral wall lip portion 32b.

The third inner peripheral wall lip portion 32b is a part of the third inner peripheral wall 32 sandwiched between the second mounting ring 47 and the head main body 2, and is formed on the upper portion of the third inner peripheral wall 32. In other words, the third inner peripheral wall lip portion 32b is connected to the tip of the third inner peripheral wall main body 32a. The second mounting ring 47 functions as an edge mounting member for the above-mentioned edge peripheral wall 33, and for the third internal peripheral wall 32, the internal mounting member for fixing the third internal peripheral wall 32 to the head main body 2. Functions as. Therefore, the second mounting ring 47 also has a seal recess 54 formed corresponding to the seal protrusion 32c of the third inner peripheral wall 32. The seal recess 54 is formed over the entire circumference of the second mounting ring 47. When the second mounting ring 47 is mounted on the head body 2 using a fastener (not shown), the third internal peripheral wall lip portion 32b is sandwiched between the head body 2 and the second mounting ring 47, whereby the third mounting ring 47 is sandwiched between the head body 2 and the second mounting ring 47. The internal peripheral wall 32 is fixed to the head body 2. Further, the seal protrusion 32c of the third inner peripheral wall 32 is pressed against the seal recess 54, whereby the gap between the second mounting ring 47 and the third inner peripheral wall lip portion 32b is sealed.

As shown in FIG. 3, the first inner peripheral wall 30 has the same shape as the third inner peripheral wall 32, and the second inner peripheral wall 31 has the second inner peripheral wall lip portion 31b not radially outside. It differs from the shape of the third inner peripheral wall 32 only in that it extends inward in the radial direction. Specifically, the first inner peripheral wall 30 has a first inner peripheral wall main body 30a extending upward from the contact portion 11 and a first inner peripheral wall lip portion 30b connected to the first inner peripheral wall main body 30a. The second inner peripheral wall 31 has a second inner peripheral wall main body 31a extending upward from the contact portion 11 and a second inner peripheral wall lip portion 31b connected to the second inner peripheral wall main body 31a. The first inner peripheral wall main body 30a and the second inner peripheral wall main body 31a extend in an annular shape around the central axis CL. The first inner peripheral wall lip portion 30b is formed in a flange shape over the entire circumference of the first inner peripheral wall main body 30a, and the second inner peripheral wall lip portion 31b is formed in a flange shape over the entire circumference of the second inner peripheral wall main body 31a. There is.

The first inner peripheral wall main body 30a is connected to an inclined portion 110 extending diagonally upward in the radial direction from the contact portion 11 and an inclined portion 110, and is connected to a horizontal portion 111 extending inward in the radial direction and a horizontal portion 111. It is composed of a vertical portion 112 extending vertically from the horizontal portion 111. The second inner peripheral wall main body 31a is connected to an inclined portion 120 extending diagonally upward in the radial direction from the contact portion 11 and an inclined portion 120, and is connected to a horizontal portion 121 extending inward in the radial direction and a horizontal portion 121. It is composed of a vertical portion 122 extending vertically from the horizontal portion 121.

Further, the first inner peripheral wall 30 has a seal protrusion 30c formed in an annular shape around the entire circumference of the first inner peripheral wall lip portion 30b, and the second inner peripheral wall 31 has the entire circumference of the second inner peripheral wall lip portion 31b. It has a seal protrusion 31c formed in an annular shape throughout.

The first mounting ring 45 functions as an internal mounting member for mounting the first internal peripheral wall 30 and the second internal peripheral wall 31 to the head body 2 (see FIG. 2). The first mounting ring 45 also has two seal recesses into which the seal protrusion 30c of the first inner peripheral wall 30 and the seal protrusion 31c of the second inner peripheral wall 31 are fitted. These seal recesses are also formed over the entire circumference of the first mounting ring 45. When the first mounting ring 45 is fixed to the head body 2 using a fastener (not shown), the first internal peripheral wall lip portion 30b and the second internal peripheral wall lip portion 31b are placed between the head body 2 and the first mounting ring 45. It is sandwiched so that the first inner peripheral wall 30 and the second inner peripheral wall 31 are fixed to the head body 2. Further, the seal protrusion 30c of the first inner peripheral wall 30 is pressed against one seal recess, and at the same time, the seal protrusion 31c of the second inner peripheral wall 31 is pressed against the other seal recess. As a result, the gap between the first mounting ring 45 and the first inner peripheral wall lip portion 30b is sealed, and at the same time, the gap between the first mounting ring 45 and the second inner peripheral wall lip portion 31b is sealed.

As described above, the elastic membrane 10 has not only flexibility but also high adhesiveness. Therefore, when the elastic film 10 is fixed to the head body 2 via the mounting rings 45 and 47, a part (or a plurality of parts) of the peripheral walls 30 to 33 of the elastic film 10 becomes the head body 2 and / or the mounting ring 45, It may stick to 47. In this case, another portion may be pulled by the close contact portion of the elastic film 10, and the degree of deformation of the elastic film 10 in the circumferential direction may vary. In particular, when the edge peripheral wall 33 located at the outermost peripheral portion of the elastic film 10 is in close contact with the head body 2 and / or the second mounting ring 47, the variation in the degree of deformation of the elastic film 10 in the circumferential direction becomes large.

Therefore, in the present embodiment, at least a part of the surface of the edge peripheral wall lip portion 33b so that the edge peripheral wall lip portion 33b of the edge peripheral wall 33 can smoothly move with respect to the head body 2 and / or the second mounting ring 47. To roughen the surface. FIG. 5 is a diagram showing a roughened surface of the edge peripheral wall lip portion 33b of the elastic film 10. In FIG. 5, the surface of the roughened edge peripheral wall lip portion 33b is drawn with a thick line.

As used herein, "surface roughening" means forming a plurality of protrusions and / or a plurality of recesses on the surface. The protrusions and / or recesses may be regularly arranged on the surface or may be irregularly (or randomly) arranged. The shape of the convex portion and the shape of the concave portion are arbitrary, and may be, for example, a hemispherical shape, a conical shape, a pyramid shape, a cylindrical shape, a prismatic shape, or the like. The height of the protrusions (ie, the distance from the surface to the top of the protrusions) and the depth of the recesses (ie, the distance from the surface to the bottom of the recesses) are also arbitrary. For example, the convex portion may be a fine convex portion having a height of about 10 μm, and similarly, the concave portion may be a fine concave portion having a depth of about 10 μm.

The method for roughening the surface of the elastic film 10 is also arbitrary. For example, various surface treatments such as sandblasting, wet blasting, and roughening using a tool such as a file may be applied to the surface of the elastic film 10 to be roughened.

However, the elastic film 10 is generally formed by curing the rubber material poured into the molding die. Therefore, the inner surface of the molding die corresponding to the surface of the elastic film 10 to be roughened may be subjected to the above surface treatment such as sandblasting. In this case, it is possible to obtain the elastic film 10 in which the roughened surface is formed at a desired position simply by removing the elastic film 10 from the molding die. That is, the elastic film 10 having the roughened surface at a desired position can be manufactured inexpensively and easily. In one embodiment, the inner surface of the molding die corresponding to the surface of the elastic film 10 to be roughened may be subjected to so-called “texturing”.

In the example shown in FIG. 5, the entire surface of the edge peripheral wall lip portion 33b is roughened. That is, the entire surface of the edge peripheral wall lip portion 33b including the upper surface, the lower surface, and the connecting surface connecting the upper surface and the lower surface is roughened. Since the edge peripheral wall lip 33b has the seal protrusion 33c on the lower surface thereof, the surface of the seal protrusion 33c is also roughened.

In one embodiment, instead of roughening the entire surface of the edge peripheral wall lip portion 33b, at least a part of the surface of the edge peripheral wall lip portion 33b may be roughened. For example, only the upper surface or the lower surface of the edge peripheral wall lip portion 33b may be roughened. Alternatively, the upper surface of the edge peripheral wall lip portion 33b and the lower surface excluding the seal protrusion 33c may be roughened.

By roughening the edge peripheral wall lip portion 33b, the contact area of the edge peripheral wall lip portion 33b with the head body 2 and / or as compared with the case where the edge peripheral wall lip portion 33b is a flat surface without unevenness. The contact area of the edge peripheral wall lip portion 33b with the second mounting ring 47 is reduced. As a result, even if the elastic film 10 has high adhesiveness, it is possible to prevent the edge peripheral wall lip portion 33b from coming into close contact with the head body 2 and / or the second mounting ring 47. Therefore, the edge peripheral wall lip portion 33b can be smoothly and easily moved with respect to the head body 2 and / or the second mounting ring 47, so that the elasticity of the elastic film 10 can be suppressed while suppressing variations in the degree of deformation in the circumferential direction. The film 10 can be easily fixed to the head body 2.

In the embodiment shown in FIG. 5, the surface of the edge peripheral wall lip portion 33b is roughened, but the present invention is not limited to this embodiment. Hereinafter, an embodiment of the elastic film 10 in which not only the surface of the edge peripheral wall lip portion 33b but also the surface of other portions are roughened will be described. Since the configuration not particularly described is the same as that of the above-described embodiment, the duplicate description will be omitted.

FIG. 6 is a diagram showing a roughened surface of the elastic film 10 according to another embodiment. Also in FIG. 6, the surface of the roughened elastic film 10 is shown by a thick line.

In the example shown in FIG. 6, in addition to the entire surface of the edge peripheral wall lip portion 33b, the inner peripheral surface of the edge peripheral wall main body 33a is also roughened. The inner peripheral surface of the edge peripheral wall main body 33a is a surface that comes into contact with or may come into contact with the outer peripheral surface of the second mounting ring 47 when the elastic film 10 is attached to the head main body 2. Therefore, by roughening the inner peripheral surface of the edge peripheral wall main body 33a, it is possible to prevent the edge peripheral wall main body 33a from coming into close contact with the second mounting ring 47. As a result, the edge peripheral wall main body 33a can be smoothly and easily moved with respect to the second mounting ring 47, so that the elastic film 10 can be moved to the head main body 2 while suppressing variation in the degree of deformation of the elastic film 10 in the circumferential direction. Can be easily fixed to.

As shown in FIG. 6, the third inner peripheral wall lip portion 32b of the third inner peripheral wall 32 may be roughened. In the example shown in FIG. 6, the entire surface of the third inner peripheral wall lip portion 32b is roughened. In one embodiment, instead of roughening the entire surface of the third inner peripheral wall lip portion 32b, at least a part of the surface of the third inner peripheral wall lip portion 32b may be roughened. For example, only the upper surface or the lower surface of the third inner peripheral wall lip portion 32b may be roughened, or the upper surface of the third inner peripheral wall lip portion 32b and the lower surface excluding the seal protrusion 32c may be roughened.

Further, the inner peripheral surface and the outer peripheral surface of the vertical portion 132 of the third inner peripheral wall main body 32a may be roughened. The inner peripheral surface of the vertical portion 132 of the third inner peripheral wall main body 32a is a surface that comes into contact with or may come into contact with the head main body 2 when the elastic film 10 is attached to the head main body 2. The outer peripheral surface of the vertical portion 132 of the third inner peripheral wall main body 32a is a surface that comes into contact with or may come into contact with the second mounting ring 47 when the elastic film 10 is attached to the head main body 2. Therefore, by roughening the inner peripheral surface and the outer peripheral surface of the third inner peripheral wall main body 32a, it is possible to prevent the third inner peripheral wall main body 32a from coming into close contact with the head main body 2 and the second mounting ring 47. As a result, the third internal peripheral wall main body 32a can be smoothly and easily moved with respect to the head main body 2 and the second mounting ring 47, so that the elasticity of the elastic film 10 can be suppressed while suppressing variations in the degree of deformation in the circumferential direction. The film 10 can be easily fixed to the head body 2.

FIG. 7 is a diagram showing the roughened surface of the elastic film 10 according to still another embodiment. Also in FIG. 7, the surface of the roughened elastic film 10 is shown by a thick line.

In the example shown in FIG. 7, in addition to the entire surface of the edge peripheral wall lip portion 33b and the entire surface of the third internal peripheral wall lip portion 32b, the entire surface of the first internal peripheral wall lip portion 30b and the second internal peripheral wall lip portion 31b. The entire surface of the surface is also roughened. In the illustrated example, the surfaces of the first inner peripheral wall lip portion 30b, the second inner peripheral wall lip portion 31b, and the third inner peripheral wall lip portion 32b are each roughened, but the present invention is not limited to this embodiment. .. For example, the surface of any one or two of the first inner peripheral wall lip portion 30b, the second inner peripheral wall lip portion 31b, and the third inner peripheral wall lip portion 32b may be roughened. Further, similarly to the edge peripheral wall lip portion 33b and the third internal peripheral wall lip portion 32b described above, at least a part of the first internal peripheral wall lip portion 30b and at least a part of the second internal peripheral wall lip portion 31b are roughened. You may.

According to the example shown in FIG. 7, the first inner peripheral wall lip portion 30b and the second inner peripheral wall lip portion 31b can be smoothly and easily moved with respect to the head body 2 and / or the first mounting ring 45. Therefore, the variation in the degree of deformation of the elastic film 10 in the circumferential direction can be further suppressed, and the elastic film 10 can be more easily fixed to the head body 2.

As shown by the alternate long and short dash line in FIG. 7, the inner peripheral surface and the outer peripheral surface of the vertical portion 112 of the first inner peripheral wall main body 30a may be roughened, or the vertical portion 122 of the second inner peripheral wall main body 31a may be roughened. The inner peripheral surface and the outer peripheral surface may be roughened. Further, the inner peripheral surface of the edge peripheral wall main body 33a of the edge peripheral wall 33 may be roughened, or the inner peripheral surface and the outer peripheral surface of the vertical portion 132 of the third peripheral wall main body 32a may be roughened.

The inner peripheral surface of the vertical portion 112 of the first inner peripheral wall main body 30a and the outer peripheral surface of the vertical portion 122 of the second inner peripheral wall main body 31a may come into contact with the head main body 2 when the elastic film 10 is attached to the head main body 2. Or a surface that may come into contact. The outer peripheral surface of the vertical portion 112 of the first inner peripheral wall main body 30a and the inner peripheral surface of the vertical portion 122 of the second inner peripheral wall main body 31a come into contact with the first mounting ring 45 when the elastic film 10 is attached to the head main body 2. Or a surface that may come into contact. Therefore, by roughening the inner peripheral surface and the outer peripheral surface of the vertical portion 112 of the first inner peripheral wall main body 30a and the inner peripheral surface and the outer peripheral surface of the vertical portion 122 of the second inner peripheral wall main body 31a, the first inner surface is roughened. It is suppressed that the peripheral wall main body 30a and the second inner peripheral wall main body 31a are in close contact with the head main body 2 and the first mounting ring 45. As a result, the first inner peripheral wall main body 30a and the second inner peripheral wall main body 31a can be smoothly and easily moved with respect to the head main body 2 and the first mounting ring 45, so that the degree of deformation of the elastic film 10 in the circumferential direction can be changed. The elastic film 10 can be more easily fixed to the head body 2 while further suppressing the variation.

FIG. 8 is a diagram showing the roughened surface of the elastic film 10 according to still another embodiment. Also in FIG. 8, the surface of the roughened elastic film 10 is shown by a thick line. In the example shown in FIG. 8, the entire surface of the elastic film 10 is roughened. Even with such a configuration, the elastic film 10 can be smoothly and easily moved with respect to the head body 2 and the mounting rings 45 and 47, so that the elasticity of the elastic film 10 can be suppressed while suppressing variations in the degree of deformation in the circumferential direction. The film 10 can be easily fixed to the head body 2. Further, since the entire surface of the elastic film 10 is roughened, the surface treatment of the elastic film 10 is easy, and the elastic film 10 can be manufactured at low cost. For example, the entire inner surface of the molding die of the elastic film 10 may be subjected to surface treatment such as sandblasting, wet blasting, or roughening using a tool such as a file, so that the molding die can be easily manufactured. , Molds and elastic membranes 10 can be manufactured at low cost.

Further, the surface of the first mounting ring 45 and / or the second mounting ring 47 may be covered with a friction reducing film. In the present specification, the "friction-reducing film" is a general term for a film formed of a low-friction material, and the "low-friction material" has a friction coefficient with respect to the elastic film 10 of mounting rings 45, 47 (mounting member). It means a material smaller than the material of the head body 2 and the material of the head body 2. The low friction material is not particularly limited as long as the friction coefficient with respect to the elastic film 10 is smaller than that of the materials of the mounting members 45 and 47 and the head body 2, but for example, a fluororesin such as Teflon (registered trademark) is used. Is.

Such a friction reducing film may be formed on the entire surface of the mounting rings 45 and 47, or may be formed only on the surface that comes into contact with or may come into contact with the elastic film 10. The friction-reducing film effectively reduces the contact of the elastic film 10 with the mounting rings 45, 47 and the head body 2, whereby the lip portions 30b, 31b, 32b, 33b of the elastic film 10 are attached to the mounting ring 45. , 47 can be moved more smoothly and easily.

In the above-described embodiment, a part or a plurality of or all of the surface of the elastic film 10 is roughened so that the contact area between the elastic film 10 and the head body 2 and / or the elastic film 10 and the mounting ring 45 The contact area with 47 is reduced. As a result, the elastic film 10 can be smoothly moved with respect to the head body 2 and the mounting rings 45 and 47. However, the same effect can be obtained by roughening the surfaces of the mounting rings 45 and 47 facing the elastic film 10 and / or the surface of the head body 2.

Specifically, instead of roughening each part of the elastic film 10 shown by the thick solid line and the alternate long and short dash line in FIGS. 5 to 7, the surfaces of the mounting rings 45 and 47 facing these parts and the head body. The surface of 2 is roughened. In this case, the entire surface of the elastic membrane 10 is a flat surface without protrusions and / or recesses. The surface of the mounting rings 45 and 47 and / or the surface of the head body 2 is roughened by surface treatment such as sandblasting, wet blasting, or roughening using a tool such as a file. In one embodiment, the surfaces of the mounting rings 45 and 47 and the surface of the head body 2 may be roughened by graining.

The above-described embodiment is described for the purpose of enabling a person having ordinary knowledge in the technical field to which the present invention belongs to carry out the present invention. Various modifications of the above embodiment can be naturally made by those skilled in the art, and the technical idea of the present invention can be applied to other embodiments. Therefore, the present invention is not limited to the described embodiments, but is construed in the broadest range according to the technical idea defined by the claims.

1 Substrate holding device (polishing head)
2 Head body 3 Retainer ring 10 Elastic membrane (membrane)
11 Contact parts 16a, 16b, 16c, 16d Pressure chamber 18 Polishing table 19 Polishing pad 27 Head shafts 30, 31, 32 Internal peripheral walls 30a, 31a, 32a Internal peripheral wall bodies 30b, 31b, 32b Internal peripheral wall lip parts 30c, 31c, 32c Seal protrusion 33 Edge peripheral wall 33a Edge peripheral wall body 33b Edge peripheral wall lip 33c Seal protrusion 40 Control device 45 Internal mounting ring (internal mounting member)
47 Edge mounting ring (edge mounting member)
54,55 Seal recess

Claims (8)

An elastic film used in a substrate holding device.
A contact portion that abuts on the substrate and presses the substrate against the polishing pad,
An edge peripheral wall extending from the peripheral end of the contact portion is provided.
The edge peripheral wall has an edge peripheral wall lip portion sandwiched between the head main body of the substrate holding device and an edge mounting member for fixing the edge peripheral wall to the head main body.
The edge peripheral wall lip portion is an elastic film characterized in that at least a part of its surface is roughened. The edge peripheral wall has an edge peripheral wall main body extending from the contact portion and connected to the edge peripheral wall lip portion.
The elastic film according to claim 1, wherein the contact surface of the edge peripheral wall main body with the edge mounting member is also roughened. Further provided with at least one internal peripheral wall arranged radially inside the edge peripheral wall and extending from the abutting portion.
The internal peripheral wall has an internal peripheral wall lip portion sandwiched between the head main body and an internal mounting member for fixing the internal peripheral wall to the head main body.
The elastic film according to claim 1 or 2, wherein at least a part of the surface of the inner peripheral wall lip portion is roughened. The internal peripheral wall has an internal peripheral wall main body extending from the contact portion and connected to the internal peripheral wall lip portion.
The elastic film according to claim 3, wherein the contact surface of the internal peripheral wall main body with the internal mounting member is also roughened. The elastic film according to any one of claims 1 to 4, wherein the entire surface of the elastic film is roughened. An elastic membrane forming at least one pressure chamber for pressing the substrate,
The head body to which the elastic film is fixed and
The elastic film is provided with at least one mounting member for fixing the elastic film to the head body.
The elastic membrane is
An abutting portion that abuts on the substrate and presses the substrate against the polishing pad,
It is provided with an edge peripheral wall extending from the peripheral end of the contact portion.
The edge peripheral wall has an edge peripheral wall lip portion sandwiched between the head main body and an edge mounting member which is one of the mounting members.
The substrate holding device is characterized in that at least a part of the surface of the edge peripheral wall lip portion is roughened. The substrate holding device according to claim 6, wherein the surface of the edge mounting member is covered with a friction reducing film. An elastic membrane forming at least one pressure chamber for pressing the substrate,
The head body to which the elastic film is fixed and
The elastic film is provided with at least one mounting member for fixing the elastic film to the head body.
The elastic membrane is
An abutting portion that abuts on the substrate and presses the substrate against the polishing pad,
It is provided with an edge peripheral wall extending from the peripheral end of the contact portion.
The edge peripheral wall has an edge peripheral wall lip portion sandwiched between the head main body and an edge mounting member which is one of the mounting members.
A substrate holding device characterized in that the surface of the edge mounting member facing the edge peripheral wall lip portion and / or the surface of the head body is roughened.

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