JP2021030410A - 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 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 on an upper part thereof, sandwiched between a head main body 2 of a substrate holding device 1 and an edge mounting member 47 for fixing the edge peripheral wall 33 to the head main body 2. The edge peripheral wall lip part 33b has a plurality of edge peripheral wall protrusions 33e, 33e', 33e'' to be fitted into first recess parts 60 formed in the edge mounting member 47 and/or second recess parts 61 formed in the head main body 2. The edge peripheral wall protrusions 33e, 33e', 33e'' are arranged at equal intervals along a circumferential direction of the edge peripheral wall 33.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.

Japanese Unexamined Patent Publication No. 2006-159392

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 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 on the upper portion thereof. The edge peripheral wall lip portion has a plurality of edge peripheral wall protrusions fitted in a first concave portion formed in the edge mounting member and / or a second concave portion formed in the head body, and the edge peripheral wall. An elastic film is provided in which the protrusions are arranged at equal intervals along the circumferential direction of the edge peripheral wall.

In one aspect, the edge peripheral wall protrusion is a vertical edge protrusion protruding from the upper surface or the lower surface of the edge peripheral wall lip portion.
In one aspect, the edge peripheral wall protrusion is a lateral edge protrusion that protrudes in the radial direction of the edge peripheral wall from the tip of the edge peripheral wall lip portion.
In one aspect, some of the edge peripheral protrusions are vertical edge protrusions protruding from the upper surface or the lower surface of the edge peripheral wall lip portion, and the rest of the edge peripheral wall protrusions are the edge peripheral wall from the tip of the edge peripheral wall lip portion. It is a lateral edge protrusion that protrudes in the radial direction of.

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, the internal peripheral wall having the head body and the head body above it. It has an internal peripheral wall lip portion sandwiched between the internal peripheral wall and an internal mounting member for fixing the internal peripheral wall to the head body, and the internal peripheral wall lip portion has a third recess formed in the edge mounting member and /. Alternatively, it has a plurality of internal peripheral wall protrusions fitted in the fourth recess formed in the head body, and the internal peripheral wall protrusions are arranged at equal intervals along the circumferential direction of the internal peripheral wall.
In one aspect, the internal peripheral wall protrusion is a vertical internal protrusion protruding from the upper surface or the lower surface of the internal peripheral wall lip portion.
In one aspect, the internal peripheral wall protrusion is a lateral internal protrusion protruding in the radial direction of the internal peripheral wall from the tip of the internal peripheral wall lip portion.
In one aspect, some of the internal peripheral protrusions are vertical internal protrusions protruding from the upper surface or the lower surface of the internal peripheral wall lip portion, and the rest of the internal peripheral wall projections are the internal peripheral wall from the tip of the internal peripheral wall lip portion. It is a lateral internal protrusion that protrudes in the radial direction of.

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. Provided is a substrate holding device, wherein the elastic film is the elastic film.

According to the present invention, the elastic film is fixed to the head body in a state where a plurality of edge peripheral wall projections arranged at equal intervals along the circumferential direction of the edge peripheral wall are fitted into the first recess and / or the second recess. To. Therefore, the elastic film can be fixed to the head body while suppressing the deformation of the elastic film in the circumferential direction to the minimum. Further, when the elastic film is fixed to the head body via the mounting member, the plurality of edge peripheral wall projections function as a guide to the head body and / or the edge mounting member. Therefore, the elastic film can be easily attached to the head body.

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 cross-sectional view taken along the line AA of FIG. FIG. 6 is an enlarged cross-sectional view of the vicinity of the edge peripheral wall of the elastic film according to another embodiment. FIG. 7 is a bottom view of the elastic membrane shown in FIG. FIG. 8 is an enlarged cross-sectional view of the vicinity of the edge peripheral wall of the elastic film according to still another embodiment. FIG. 9 is a schematic view showing an enlarged edge peripheral wall of the elastic film 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). FIG. 5 is a cross-sectional view taken along the line AA of FIG.

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, the edge peripheral wall lip portion 33b of the edge peripheral wall 33 has a plurality of edge peripheral wall projections 33e protruding inward in the radial direction from the tip end (inner peripheral end). As shown in FIG. 5, the edge peripheral wall lip portion 33b according to the present embodiment has six edge peripheral wall protrusions 33e arranged at equal intervals along the circumferential direction of the edge peripheral wall 33. Each edge peripheral wall projection 33e has an arc shape in a horizontal cross-sectional view as shown in FIG. 5, and projects horizontally from the tip of the edge peripheral wall lip portion 33b inward in the radial direction of the edge peripheral wall 33. In the following description, the edge peripheral wall projection 33e protruding in the radial direction of the edge peripheral wall lip portion 33b may be referred to as a "lateral edge projection 33e".

As shown in FIGS. 4 and 5, the second mounting ring 47 has a plurality of recesses 60 (six in FIG. 5) formed corresponding to the edge protrusions 33e. These recesses 60 have a shape corresponding to the lateral edge protrusions 33e, and are arranged at equal intervals along the circumferential direction of the second mounting ring 47.

When the elastic film 10 is fixed to the head body 2 via the mounting rings 45 and 47, the lateral edge protrusion 33e provided on the edge peripheral wall lip portion 33b of the edge peripheral wall 33 is formed in the second mounting ring 47. It is fitted in 60. In this state, the second mounting ring 47 is fixed to the head body 2 by a fastener (not shown) such as a screw, whereby the edge peripheral wall 33 is fixed to the head body 2. That is, in a state where a plurality of lateral edge protrusions 33e arranged along the circumferential direction of the edge peripheral wall 33 are fitted into the recess 60 formed in the second mounting ring 47, the edge peripheral wall 33 passes through the second mounting ring 47. Is fixed to the head body 2. Therefore, the edge peripheral wall 33 can be fixed to the head main body 2 while suppressing the deformation of the edge peripheral wall 33 in the circumferential direction to the minimum.

Further, when the elastic film 10 is fixed to the head body 2 via the mounting rings 45 and 47, the plurality of edge peripheral wall projections 33e function as guides for the second mounting ring 47. Therefore, the elastic film 10 can be easily attached to the head body 2. In order to easily insert the lateral edge protrusion 33e into the recess 60, the lateral edge protrusion 33e preferably has a tapered shape in which the cross-sectional area decreases toward the tip thereof.

In the examples shown in FIGS. 4 and 5, six lateral edge protrusions 33e and six recesses 60 corresponding to these lateral edge protrusions 33e are provided, but the number of lateral edge protrusions 33e and the recesses 60 are provided. The number of is not limited to this example. The number of the lateral edge protrusions 33e and the number of the recesses 60 are arbitrary as long as they are arranged at equal intervals in the circumferential direction of the edge peripheral wall 33. Preferably, the number of lateral edge protrusions 33e and the number of recesses 60 are in the range of 2-8. Further, the lateral edge protrusion 33e has a tapered shape in the vertical cross-sectional view shown in FIG. 4 and an arc shape in the horizontal cross-sectional view shown in FIG. 5, but the shape of the lateral edge protrusion 33e is also limited to this example. Not done. For example, the lateral edge protrusion 33e may have a rectangular shape or a triangular shape in a vertical cross-sectional view. Preferably, the lateral edge protrusion 33e is rotationally symmetric with the central axis CL as the axis of symmetry (see FIG. 5).

As shown in FIGS. 3 and 4, the third inner peripheral wall lip portion 32b of the third inner peripheral wall 32 has a plurality of internal peripheral wall protrusions that project radially outward and horizontally from the tip end (outer peripheral end) of the inner peripheral wall 33. It may have 32d. In the following description, the internal peripheral wall projection 32d protruding in the radial direction of the third internal peripheral wall 32 may be referred to as a “lateral internal projection 32d”.

The third inner peripheral wall lip portion 32b according to the present embodiment has a plurality of lateral internal protrusions 32d arranged at equal intervals along the circumferential direction of the third inner peripheral wall 32. The number of the lateral internal protrusions 32d is arbitrary as long as they are arranged at equal intervals in the circumferential direction of the third internal peripheral wall 32, and is preferably in the range of 2 to 8. Further, the shape of the lateral internal projection 32d is also arbitrary as in the lateral edge projection 33e. The lateral internal protrusion 32d preferably has a tapered shape in which the cross-sectional area decreases toward the tip thereof. Preferably, the lateral internal projection 32d is rotationally symmetric with the central axis CL as the axis of symmetry.

The second mounting ring 47 has a plurality of recesses 62 formed corresponding to the lateral internal protrusions 32d. When the elastic film 10 is fixed to the head body 2 via the mounting rings 45 and 47, a plurality of lateral internal protrusions 32d arranged along the circumferential direction of the third internal peripheral wall 32 are formed on the second mounting ring 47. It is fitted into the recess 62, and in this state, the third inner peripheral wall 32 is fixed to the head body 2 via the second mounting ring 47.

Since the elastic film 10 has the lateral internal protrusion 32d of the third inner peripheral wall lip portion 32b in addition to the lateral edge protrusion 33e of the edge peripheral wall lip portion 33b, the degree of deformation of the elastic film 10 in the circumferential direction varies more effectively. Can be suppressed.

Further, as shown by the dotted line in FIG. 3, a plurality of first inner peripheral wall lip portions 30b of the first inner peripheral wall 30 and second internal peripheral wall lip portions 31b of the second inner peripheral wall 31 also project radially from their tips. It may have lateral internal protrusions 30d and 31d. The lateral internal projection 30d of the first internal peripheral wall lip portion 30b projects radially outward and horizontally from the tip of the first internal peripheral wall lip portion 30b, and the lateral internal projection 31d of the second internal peripheral wall lip portion 31b is the second interior. It projects radially inward and horizontally from the tip of the peripheral wall lip portion 31b. The lateral internal projection 30d of the first internal peripheral wall lip portion 30b has the same configuration as the lateral internal projection 32d of the third internal peripheral wall lip portion 32b. The lateral internal projection 31d of the second internal peripheral wall lip portion 31b has the same configuration as the lateral internal projection 32d except that the projecting direction thereof is different from the lateral internal projection 32d of the third internal peripheral wall lip portion 32b.

The first mounting ring 45 is formed corresponding to a plurality of recesses formed corresponding to the lateral internal protrusions 30d of the first inner peripheral wall lip portion 30b and the lateral internal protrusions 31d of the second inner peripheral wall lip portion 31b. It has a plurality of recesses. When the elastic film 10 is fixed to the head body 2 via the mounting rings 45 and 47, the plurality of lateral internal protrusions 30d arranged along the circumferential direction of the first internal peripheral wall 30 and the second internal peripheral wall 31 A plurality of lateral internal protrusions 31d arranged along the circumferential direction are fitted into a plurality of recesses formed in the first mounting ring 45, respectively, and in this state, the first internal peripheral wall 30 and the second internal peripheral wall 31 are first. It is fixed to the head body 2 via the mounting ring 45.

As described above, not only the edge peripheral wall lip portion 33b, but also the first internal peripheral wall lip portion 30b, the second internal peripheral wall lip portion 31b, and the third internal peripheral wall lip portion 32b each have lateral internal protrusions 30d, 31d, and 32d. You may be doing it. In one embodiment, 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 have lateral internal protrusions. With such a configuration, it is possible to more effectively suppress the variation in the degree of deformation of the elastic film 10 in the circumferential direction. Further, since the lateral internal projection 30d of the first internal peripheral wall lip portion 30b and the lateral internal projection 31d of the second internal peripheral wall lip portion 31b function as a guide with respect to the first mounting ring 45, the elastic film 10 can be headed more easily. It can be fixed to the main body 2.

FIG. 6 is an enlarged cross-sectional view of the vicinity of the edge peripheral wall 33 of the elastic film 10 according to another embodiment. FIG. 7 is a bottom view of the elastic membrane 10 shown in FIG. In FIG. 7, each lip portion 30b to 33b of the peripheral walls 30 to 33 is extracted and drawn. Since the configuration not particularly described is the same as that of the above-described embodiment, the duplicate description will be omitted.

The edge peripheral wall lip portion 33b of the edge peripheral wall 33 shown in FIGS. 6 and 7 has a plurality of (six in FIG. 7) edge protrusions 33e'protruding downward from the lower surface thereof. In the following description, the edge protrusion 33e'protruding downward from the lower surface of the edge peripheral wall lip portion 33b may be referred to as "vertical edge protrusion 33e'".

The plurality of vertical edge protrusions 33e'are arranged at equal intervals in the radial direction of the edge peripheral wall 33. The second mounting ring 47 has a plurality of recesses 60 formed corresponding to the plurality of vertical edge protrusions 33e'. The number of the vertical edge protrusions 33e'and the number of the recesses 60 are arbitrary as long as they are arranged at equal intervals in the circumferential direction of the edge peripheral wall 33, and preferably in the range of 2 to 8. It is in. Further, the shape of the vertical edge protrusion 33e'is also arbitrary as in the case of the horizontal edge protrusion 33e. Preferably, the vertical edge protrusion 33e'has a tapered shape in which the cross-sectional area decreases toward the tip thereof (see FIG. 6), and has an arc shape in a horizontal cross-sectional view (see FIG. 7). Further, it is preferable that the plurality of vertical edge protrusions 33e'are rotationally symmetric with the central axis CL as the axis of symmetry.

Also in the present embodiment, the edge peripheral wall 33 is second-mounted in a state where a plurality of vertical edge protrusions 33e'arranged along the circumferential direction of the edge peripheral wall 33 are fitted into the recess 60 formed in the second mounting ring 47. It is fixed to the head body 2 via the ring 47. Therefore, the edge peripheral wall 33 can be fixed to the head main body 2 while suppressing the deformation of the edge peripheral wall 33 in the circumferential direction to the minimum. Further, when the elastic film 10 is fixed to the head body 2 via the mounting rings 45 and 47, the plurality of vertical edge protrusions 33e'function as a guide for the second mounting ring 47. Therefore, the elastic film 10 can be easily attached to the head body 2. As described above, the edge peripheral wall protrusion may protrude downward from the lower surface of the edge peripheral wall lip portion 33b like the vertical edge protrusion 33e'.

As shown in FIGS. 6 and 7, the third internal peripheral wall lip portion 32b of the third internal peripheral wall 32 has a plurality of (six in FIG. 7) internal protrusions 32d'protruding downward from the lower surface thereof. You may. In the following description, the internal protrusion 32d'protruding downward from the lower surface of the third inner peripheral wall lip portion 32b may be referred to as "vertical internal protrusion 32d'".

The plurality of vertical internal protrusions 32d'are arranged at equal intervals along the circumferential direction of the third internal peripheral wall 32. The second mounting ring 47 has a plurality of recesses 62 formed corresponding to the plurality of vertical internal protrusions 32d'. The number of the vertical internal protrusions 32d'and the number of the recesses 62 are also arbitrary as long as they are arranged at equal intervals in the circumferential direction of the third internal peripheral wall 32, like the vertical edge protrusions 33e', and are preferably 2 to 8. It is in the range of pieces. Further, the shape of the vertical internal protrusion 32d'is also arbitrary as in the case of the vertical edge protrusion 33e'. Preferably, the vertical internal protrusion 32d'has a tapered shape in which the cross-sectional area decreases toward the tip thereof (see FIG. 6), and has an arc shape in a horizontal cross-sectional view (see FIG. 7). Further, it is preferable that the plurality of vertical internal protrusions 32d'are rotationally symmetric with the central axis CL as the axis of symmetry.

As shown by the dotted line in FIG. 7, the first inner peripheral wall lip portion 30b of the first inner peripheral wall 30 and the second inner peripheral wall lip portion 31b of the second inner peripheral wall 31 also have a plurality of vertical interiors protruding downward from the lower surface thereof. It may have protrusions 30d'and 31d'. The vertical internal projection 30d'of the first internal peripheral wall lip portion 30b and the vertical internal projection 31d'of the second internal peripheral wall lip portion 31b have the same configuration as the vertical internal projection 32d'of the third internal peripheral wall lip portion 32b. Although not shown, the first mounting ring 45 has a plurality of recesses formed corresponding to the vertical internal protrusions 30d'of the first internal peripheral wall lip portion 30b, and the vertical internal protrusions 31d'of the second internal peripheral wall lip portion 31b. It has a plurality of recesses formed corresponding to.

As described above, not only the edge peripheral wall lip portion 33b but also the first internal peripheral wall lip portion 30b, the second internal peripheral wall lip portion 31b, and the third internal peripheral wall lip portion 32b have vertical internal protrusions 30d', 31d', 32d, respectively. May have a'. In one embodiment, 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 have vertical internal protrusions. With such a configuration, it is possible to more effectively suppress the variation in the degree of deformation of the elastic film 10 in the circumferential direction. Further, since the vertical internal protrusion 30d'of the first inner peripheral wall lip portion 30b and the vertical internal protrusion 31d'of the second inner peripheral wall lip portion 31b function as a guide with respect to the first mounting ring 45, the elastic film 10 can be more easily formed. Can be fixed to the head body 2.

FIG. 8 is an enlarged cross-sectional view of the vicinity of the edge peripheral wall 33 of the elastic film 10 according to still another embodiment. Since the configuration of the present embodiment, which is not particularly described, is the same as that of the embodiments shown in FIGS. 6 and 7, the duplicate description thereof will be omitted.

The edge peripheral wall lip portion 33b of the edge peripheral wall 33 shown in FIG. 8 has a plurality of vertical edge protrusions 33e ″ protruding upward from the upper surface thereof. Also in this embodiment, the plurality of vertical edge protrusions 33e ″ are arranged at equal intervals along the circumferential direction of the edge peripheral wall 33. The head body 2 has a plurality of recesses 61 formed corresponding to the vertical edge protrusions 33e ″.

In the present embodiment, the edge peripheral wall 33 is the second mounting ring in a state where a plurality of vertical edge protrusions 33e'' arranged along the circumferential direction of the edge peripheral wall 33 are fitted into the recesses 61 formed in the head body 2. It is fixed to the head body 2 via 47. Even in this case, the edge peripheral wall 33 can be fixed to the head main body 2 while suppressing the deformation of the edge peripheral wall 33 in the circumferential direction to the minimum. Further, when the elastic film 10 is fixed to the head body 2 via the mounting rings 45 and 47, the plurality of vertical edge protrusions 33e ″ function as a guide with respect to the head body 2. Therefore, the elastic film 10 can be easily attached to the head body 2. As described above, the edge peripheral wall protrusion may protrude upward from the upper surface of the edge peripheral wall lip portion 33b like the vertical edge protrusion 33e ″.

As shown in FIG. 8, the third inner peripheral wall lip portion 32b of the third inner peripheral wall 32 may also have a vertical internal protrusion 32d ″ protruding from the upper surface thereof. The head body 2 has a plurality of recesses 63 formed corresponding to the vertical internal protrusions 32d ″. Although not shown, the first inner peripheral wall lip portion 30b of the first inner peripheral wall 30 and the second inner peripheral wall lip portion 31b of the second inner peripheral wall 31 each have vertical internal protrusions protruding from the upper surface thereof. May be good. In this case, the head main body 2 has a plurality of recesses formed corresponding to the vertical internal protrusions of the first internal peripheral wall lip portion 30b and the vertical internal protrusions of the second internal peripheral wall lip portion 31b. In one embodiment, 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 have vertical internal protrusions.

Even with such a configuration, it is possible to effectively suppress variations in the degree of deformation of the elastic film 10 in the circumferential direction. Further, since the vertical internal protrusions of the first internal peripheral wall lip portion 30b and the vertical internal protrusions of the second internal peripheral wall lip portion 31b also function as guides to the head main body 2, the elastic film 10 is easily fixed to the head main body 2. be able to.

FIG. 9 is a schematic view showing an enlarged edge peripheral wall 33 of the elastic film 10 according to still another embodiment. Since the configuration of the present embodiment not particularly described is the same as the configuration of the above-described embodiment, the duplicate description will be omitted.

The edge peripheral wall 33 shown in FIG. 9 has an edge peripheral wall main body 33a extending obliquely upward from the peripheral end portion of the contact portion 11, and an edge peripheral wall lip portion 33b extending from the tip of the edge peripheral wall main body 33a. In the above-described embodiment, the edge peripheral wall main body 33a extends upward in the vertical direction from the peripheral end portion of the contact portion 11, but the present invention is not limited to these embodiments. The shape of the edge peripheral wall main body 33a is arbitrary, and may extend diagonally upward, for example, as shown in FIG.

Further, the edge peripheral wall lip portion 33b of the edge peripheral wall 33 shown in FIG. 9 has an edge protrusion 33e ″ protruding upward from the upper surface thereof. However, as shown by the dotted line in FIG. 9, the edge peripheral wall lip portion 33b may have an edge protrusion 33e'protruding downward from the lower surface of the edge peripheral wall lip portion 33b, or the tip of the edge peripheral wall lip portion 33b. It may have a lateral edge protrusion 33e protruding in the radial direction from the.

Although not shown, the shapes of the internal peripheral wall bodies 30a, 31a, 32a of the internal peripheral walls 30, 31, 32 are also arbitrary, and extend diagonally upward from the contact portion 11 like the edge peripheral wall 33 shown in FIG. May be good. Further, the shapes of the inner peripheral wall bodies 30a, 31a, 32a of the inner peripheral walls 30, 31, 32 may be the same as or different from each other.

In the above-described embodiment, the edge peripheral wall lip portion 33b of the edge peripheral wall 33 has any of a horizontal edge protrusion 33e, a vertical edge protrusion 33e', and a vertical edge protrusion 33e''. It is not limited to the embodiment. For example, the edge peripheral wall lip portion 33b may have two of the horizontal edge protrusion 33e, the vertical edge protrusion 33e', and the vertical edge protrusion 33e'', and these protrusions 33e, 33e', 33e'. You may have all of'. Similarly, each of the internal peripheral wall lip portions 30b to 32b has a lateral internal projection protruding radially from the tip of each internal peripheral wall lip portion 30b to 32b, and a vertical internal projection protruding from the upper surface of each internal peripheral wall lip portion 30b to 32b. And two of the vertical internal protrusions protruding from the lower surface of each internal peripheral wall lip portion 30b to 32b may be provided, or all of these protrusions may be provided.

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 32d Horizontal internal protrusion 32d', 32d'' Vertical internal protrusion 33 Edge peripheral wall 33a Edge peripheral wall body 33b Edge peripheral wall lip 33c Seal protrusion 33e Horizontal edge protrusion 33e', 33e'' Vertical edge protrusion 40 Control device 45 Internal mounting Ring (internal mounting member)
47 Edge mounting ring (edge mounting member)
54, 55 Seal recess 60 1st recess 61 2nd recess 62 3rd recess 63 4th recess

Claims (9)

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 on the upper portion thereof.
The edge peripheral wall lip portion has a plurality of edge peripheral wall protrusions fitted in a first recess formed in the edge mounting member and / or a second recess formed in the head body.
The elastic film is characterized in that the edge peripheral wall protrusions are arranged at equal intervals along the circumferential direction of the edge peripheral wall. The elastic film according to claim 1, wherein the edge peripheral wall protrusion is a vertical edge protrusion protruding from the upper surface or the lower surface of the edge peripheral wall lip portion. The elastic film according to claim 1, wherein the edge peripheral wall protrusion is a lateral edge protrusion protruding in the radial direction of the edge peripheral wall from the tip of the edge peripheral wall lip portion. Some of the edge peripheral protrusions are vertical edge protrusions protruding from the upper surface or the lower surface of the edge peripheral wall lip portion.
The elastic film according to claim 1, wherein the rest of the edge peripheral wall protrusions are lateral edge protrusions protruding in the radial direction of the edge peripheral wall from the tip of the edge peripheral wall lip portion. 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 on the upper portion thereof.
The internal peripheral wall lip portion has a plurality of internal peripheral wall projections that are fitted into a third recess formed in the edge mounting member and / or a fourth recess formed in the head body.
The elastic film according to any one of claims 1 to 4, wherein the internal peripheral wall protrusions are arranged at equal intervals along the circumferential direction of the internal peripheral wall. The elastic film according to claim 5, wherein the internal peripheral wall protrusion is a vertical internal protrusion protruding from the upper surface or the lower surface of the inner peripheral wall lip portion. The elastic film according to claim 5, wherein the internal peripheral wall protrusion is a lateral internal protrusion protruding from the tip of the internal peripheral wall lip portion in the radial direction of the internal peripheral wall. Some of the internal peripheral wall protrusions are vertical internal protrusions protruding from the upper surface or the lower surface of the internal peripheral wall lip portion.
The elastic film according to claim 5, wherein the rest of the internal peripheral wall protrusions are lateral internal protrusions protruding in the radial direction of the internal peripheral wall from the tip of the internal peripheral wall lip portion. 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 substrate holding device according to any one of claims 1 to 8, wherein the elastic film is the elastic film.

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