Polishing pad manufacturing method

Abstract

To provide a method for manufacturing a polishing pad which suppresses generation of air bubbles when a curable resin is cured in a state of being brought into contact with a member for an end point detection window suspended from above a mold and fixed thereto.SOLUTION: A method for manufacturing a polishing pad having a polishing layer with an end point detection window includes a curing step of fixing a member for an end point detection window into a mold, curing a curable resin in a state of being brought into contact with the member for the end point detection window, and forming a resin sheet in which the member for the end point detection window is incorporated, and a slice step of slicing the resin sheet and forming a polishing layer, wherein in the curing step, the member for the end point detection window is suspended and fixed by a position fixing jig installed in the mold upper part, and a lower end of the member for the end point detection window when suspended and fixed has a convex shape.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a polishing pad. [Background technology]

[0002] In semiconductor manufacturing processes, chemical mechanical polishing (CMP) is used for planarization after insulating film deposition and for forming metal wiring. One of the important technologies required for chemical mechanical polishing is polishing endpoint detection, which detects whether the polishing process is complete. For example, over-polishing or under-polishing relative to the target polishing endpoint directly leads to product defects. Therefore, in chemical mechanical polishing, the amount of polishing must be strictly controlled by polishing endpoint detection.

[0003] Chemical mechanical polishing is a complex process, and the polishing speed (polishing rate) varies depending on the operating conditions of the polishing equipment, the quality of consumables (slurry, polishing pads, dressers, etc.), and variations in conditions over time during the polishing process. Furthermore, in recent years, the precision of remaining film thickness and in-plane uniformity required in semiconductor manufacturing processes have become increasingly strict. For these reasons, detecting the polishing endpoint with sufficient precision has become more difficult.

[0004] The main methods for detecting the polishing endpoint include the optical endpoint detection method, the torque endpoint detection method, and the eddy current endpoint detection method. In the optical endpoint detection method, the endpoint is detected by irradiating the wafer with light through a transparent window member provided on the polishing pad and monitoring the reflected light.

[0005] As an example of a method for manufacturing a polishing pad using such an optical endpoint detection method, Patent Document 1 discloses a method for manufacturing a polishing pad in which a liner is provided on the bottom surface of a mold to fix a window block, and then a curable material is filled into the mold and cured. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-197597 Summary of the Invention [Problem to be solved by the invention]

[0007] However, with the method of fixing the window block at the bottom of the mold as in Patent Document 1, if the liner deforms due to heat during curing, the window block cannot be fixed perpendicularly to the mold, which is a problem. Also, because the window block is fixed directly to the liner, it is difficult to reuse, which raises manufacturing costs.

[0008] Therefore, instead of fixing the end point detection window component to the bottom surface of the mold, the inventors investigated the idea of hanging and fixing the end point detection window component from above the mold and then hardening the resin inside the mold.However, they found that air bubbles are likely to form around the end point detection window component when it is fixed by hanging it.

[0009] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a method for manufacturing a polishing pad that is less likely to produce bubbles when a curable resin is cured while in contact with an end-point detection window component that is suspended and fixed above a mold. [Means for solving the problem]

[0010] That is, the present invention is as follows. [1] A method for manufacturing a polishing pad having a polishing layer with an endpoint detection window, comprising: a curing step of fixing an end point detection window member in a mold and curing the curable resin in contact with the end point detection window member to form a resin sheet incorporating the end point detection window member; a slicing step of slicing the resin sheet to form an abrasive layer, In the curing step, the end-point detection window member is suspended and fixed by a position fixing jig installed on an upper portion of the mold, The lower end of the end point detection window member when suspended and fixed has a convex shape. A method for manufacturing a polishing pad. [2] In the curing step, after filling the mold with a curable resin, the end-point detection window member is brought into contact with the curable resin to cure the curable resin. A method for manufacturing the polishing pad described in [1]. [3] In the curing step, the end point detection window member is fixed in the mold, and then a curable resin is filled in the mold and cured. A method for manufacturing the polishing pad described in [1]. [4] The method further includes a window member forming step of forming the end point detection window member, at least one end of which has the convex shape. A method for producing the polishing pad according to any one of [1] to [3]. [5] The length L of the portion of the end-point detection window member having the convex shape is 3.0 to 20 mm. A method for producing the polishing pad according to any one of [1] to [4]. [6] the ratio (L / S) of the length L of the portion of the end-point detection window member having the convex shape to the horizontal cross-sectional area S of the end-point detection window member is 0.002 to 0.4; A method for producing a polishing pad according to any one of [1] to [5]. [7] The length L of the portion of the end-point detection window member having the convex shape is 0.03 to 0.30Lw with respect to the total length Lw of the end-point detection window member. A method for producing a polishing pad according to any one of [1] to [6]. [8] The position fixing jig has a first fitting portion that fits with the upper part of the mold. A method for producing the polishing pad according to any one of [1] to [7]. [9] The mold has a second fitting portion that fits with the position fixing jig. A method for producing a polishing pad according to any one of [1] to [8].

[10] The position fixing jig has a positioning portion that positions and fixes the end point detection window member. A method for producing a polishing pad according to any one of [1] to [9].

[11] a groove forming step of forming grooves on the polishing surface of the polishing layer, No groove processing is performed on the exposed portion of the end point detection window member before the groove forming step. A method for producing a polishing pad according to any one of [1] to

[10] .

[12] a lamination step of laminating a base layer and / or a cushion layer on the surface of the polishing layer opposite to the polishing surface, A method for producing a polishing pad according to any one of [1] to

[11] . [Effects of the Invention]

[0011] According to the present invention, a method for manufacturing a polishing pad can be provided that is less likely to produce bubbles when a curable resin is cured while in contact with an end point detection window member that is suspended and fixed above a mold. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 2 is a perspective view showing one aspect of a member for an end-point detection window according to the present embodiment. [Figure 2] FIG. 10 is a perspective view showing another example of an end-point detection window member according to the present embodiment. [Figure 3] 10 is a perspective view showing an example in which the end-point detection window member of the present embodiment is clamped by a clamping portion. FIG. [Figure 4] 10 is a perspective view showing another example in which the end-point detection window member of the present embodiment is clamped by the clamping portion. FIG. [Figure 5] FIG. 2 is a top view showing one embodiment of a combination of a mold and a position fixing jig for producing a resin sheet used in this embodiment. [Figure 6]FIG. 10 is a top view showing another embodiment in which a mold and a position fixing jig are combined to produce a resin sheet used in this embodiment. [Figure 7] FIG. 6 is a cross-sectional view showing the AA' cross section of the mold shown in FIG. 5 before the hardening resin is poured into it. [Figure 8] 6 is a cross-sectional view showing the AA' cross section of the mold shown in FIG. 5 after the hardening resin has been poured into it. FIG. [Figure 9] FIG. 3 is a top view showing the resin sheet obtained after the curing process. [Figure 10] 10 is a cross-sectional view of the resin sheet obtained after the curing process, near the end point detection window. FIG. [Figure 11] 1 is a schematic perspective view of a polishing pad according to an embodiment of the present invention. [Figure 12] 3 is a schematic cross-sectional view of an end point detection window portion of the polishing pad of the present embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail with reference to the drawings as necessary, but the present invention is not limited to this, and various modifications are possible without departing from the spirit of the present invention. In the drawings, the same elements are given the same reference numerals, and duplicated explanations will be omitted. Furthermore, positional relationships such as up, down, left, and right will be based on the positional relationships shown in the drawings unless otherwise specified. Furthermore, the dimensional ratios of the drawings are not limited to those shown in the drawings.

[0014] 1. Manufacturing method of polishing pad The method for manufacturing a polishing pad of this embodiment includes a curing process in which an end point detection window member is fixed in a mold and a curable resin is cured while in contact with the end point detection window member to form a resin sheet incorporating the end point detection window member, and a slicing process in which the resin sheet is sliced to form a polishing layer.In the curing process, the end point detection window member is hung and fixed by a position fixing jig installed on the top of the mold, and the lower end of the end point detection window member is configured to have a convex shape when hung and fixed, thereby manufacturing a polishing pad having a polishing layer with an end point detection window.

[0015] In this way, by suspending and fixing the endpoint detection window member by a position fixing jig installed on the top of the mold, the mold itself does not need to be processed to fix the endpoint detection window member, and a conventional one can be used as is. Furthermore, the position fixing jig can be used multiple times, so it does not need to be disposable like a liner. Furthermore, by suspending and fixing the endpoint detection window member by a position fixing jig installed on the top of the mold, the embedding position of the endpoint detection window member can be fine-tuned until the curable resin hardens, and such fine adjustments can also improve product yield.

[0016] However, if a component with a flat bottom is used as a suspended and fixed component for the endpoint detection window, air may accumulate when the curable resin is poured into the mold. With no way to escape, the air remains near the endpoint detection window even as the curable resin hardens, and when the polishing pad is sliced, the air appears as a void (hole). Such voids in the polishing pad may result in a decrease in polishing performance.

[0017] In contrast, in this embodiment, the lower end of the endpoint detection window member is configured to have a convex shape when suspended and fixed. Because the surface of the endpoint detection window member that protrudes toward the bottom surface of the mold has a convex shape, air existing between the lower end of the endpoint detection window member and the bottom surface of the mold can be easily released, reducing the amount of air bubbles that form around the window in the resulting polishing pad, and providing a polishing pad with stable polishing performance.

[0018] 1.1. Window component forming process The method for manufacturing a polishing pad of this embodiment may further include a window member forming step of forming an endpoint detection window member having at least one end in a convex shape before the curing step. The method for forming the endpoint detection window member 10 is not particularly limited, but it can be produced, for example, by injecting a resin into a mold (not shown) having a shape corresponding to the convex shape and curing it, or by cutting a cured product of any shape to form a convex shape after curing.

[0019] 1.1.1.End-point detection window component The end point detection window member 10 is not particularly limited as long as the lower end 10a has a convex shape, but examples include a rectangular parallelepiped member as shown in Figure 1 and a cylindrical member as shown in Figure 2.

[0020] 1, the rectangular parallelepiped endpoint detection window member 10 has a convex shape at the lower end 10a in the hanging direction of the columnar portion 11. Such a convex surface makes it easier for the curable resin to flow between the lower end 10a of the endpoint detection window member 10 and the bottom surface 21 of the mold 20, making it easier to prevent air bubbles from being trapped in the curable resin and to make it easier for trapped air bubbles to escape.

[0021] 2, the cylindrical endpoint detection window member 10 may have, for example, a convex lower end 10a of the columnar portion 11 in the hanging direction, and may further have a base portion 12 on the opposite side of the lower end 10a of the columnar portion 11. The cross-sectional shape of the columnar portion 11 is not particularly limited, and may be circular or polygonal.

[0022] Here, the columnar portion 11 is a portion that will be embedded in the resin sheet 50 and become the endpoint detection window 51 after the curing process. The base portion 12 is a portion for fixing the cylindrical endpoint detection window member 10 to the position fixing jig 30. For example, when the position fixing jig 30 and the endpoint detection window member 10 are fixed with an adhesive, the base portion 12 can increase the contact area. Furthermore, when the position fixing jig 30 and the endpoint detection window member 10 are fixed with the clamping portion 31, when the endpoint detection window member 10 is inserted into the clamping portion 31 of the position fixing jig 30 from above, it is locked by the base portion 12, and the cylindrical endpoint detection window member 10 is fixed in place without falling off.

[0023] In this way, by configuring the cylindrical endpoint detection window member 10 to have a shape including a pillar portion 11 and a base portion 12, the pillar portion 11 can be made relatively small within the range necessary for the endpoint detection window, while the base portion 12 can further prevent it from falling off. This tends to prevent the endpoint detection window member 10 from being displaced or tilted due to the resin injected during the curing process or the resin being cured. Furthermore, because the pillar portion 11 can be configured relatively small within the range necessary for the endpoint detection window, the impact of embedding the endpoint detection window on the polishing characteristics of the polishing pad can be further reduced. Note that the shape of the endpoint detection window member 10 is not limited to that shown in FIG. 2 . The cylindrical endpoint detection window member 10 may have only the pillar portion 11 without the base portion 12.

[0024] In this embodiment, the term "convex shape" refers to a surface that rises from the end toward a desired portion. For example, in Fig. 1, the rectangular parallelepiped end-point detection window member 10 has a convex shape in which both ends of the bottom surface in the long axis direction are low and gradually rise toward the center in the long axis direction. The convex shape does not have to be curved as long as it is convex, and any shape that is convex toward the center can be selected, including curved surfaces or pointed shapes such as a triangular pyramid.

[0025] In the "convex shape" of this embodiment, the highest part may be flat, but the area S1 of the highest part is preferably 0 to 50 area %, more preferably 0 to 40 area %, even more preferably 0 to 30 area %, still more preferably 0 to 20 area %, and even more preferably 0 to 10 area % of the cross-sectional area S of the end-point detection window member 10. When the ratio of the area S1 to the cross-sectional area S is 50 area % or less, the curable resin can easily flow between the lower surface of the end-point detection window member 10 and the bottom surface 21 of the mold 20, which makes it easier to prevent air bubbles from being trapped in the curable resin and also makes it easier for trapped air bubbles to escape.

[0026] In addition, the fact that the ratio of the area S1 to the cross-sectional area S is 50% or less also means that the ``convex shape'' in this embodiment does not include cases where the lower end of the end point detection window member is simply chamfered.

[0027] The length L of the portion of the endpoint detection window member 10 having a convex shape is preferably 3.0 to 20 mm, more preferably 3.0 to 15 mm, and even more preferably 3.0 to 10 mm. The longer the length L, the greater the difference between the lowest and highest points of the convex shape, which tends to more easily prevent the curable resin from trapping air bubbles and to more easily allow trapped air bubbles to escape. On the other hand, the shorter the length L, the shorter the portion that cannot be used as a polishing pad and is discarded tends to be.

[0028] The ratio (L / S) of the length L of the portion having the convex shape of the endpoint detection window member 10 to the horizontal cross-sectional area S of the endpoint detection window member 10 is preferably 0.002 to 0.4, more preferably 0.005 to 0.35, and even more preferably 0.010 to 0.30. The larger the ratio (L / S), the greater the difference between the lowest and highest points of the convex shape, which tends to more easily prevent the curable resin from trapping air bubbles and to more easily allow trapped air bubbles to escape. On the other hand, the smaller the ratio (L / S), the shorter the portion that cannot be used as a polishing pad and is discarded tends to be.

[0029] The length L of the portion of the endpoint detection window member 10 having a convex shape is preferably 0.03 to 0.30Lw, more preferably 0.03 to 0.25Lw, and even more preferably 0.03 to 0.20Lw, relative to the total length Lw of the endpoint detection window member 10. The longer the length L, the greater the difference between the lowest and highest points of the convex shape, which tends to more easily prevent air bubbles from being trapped in the curable resin and to more easily allow trapped air bubbles to escape. On the other hand, the shorter the length L, the shorter the portion that cannot be used as a polishing pad and is discarded tends to be.

[0030] It is preferable that the side surfaces of the columnar portions 11 of the endpoint detection window member 10 removed from the mold be treated with sandpaper or a solvent. This makes it possible to remove any release agent adhering to the endpoint detection window member 10, and also roughening the side surfaces with sandpaper tends to further improve adhesion between the resin sheet 50 and the endpoint detection window member 10 (endpoint detection window 51) when the endpoint detection window member 10 is embedded in the resin sheet 50.

[0031] 1.2.Curing process The curing process is a process in which a component for an end point detection window is fixed in a mold, and the curable resin is cured while in contact with the component for an end point detection window to form a resin sheet incorporating the component for an end point detection window.

[0032] 1.2.1. Positioning fixture In the curing step, the endpoint detection window member 10 is suspended and fixed by a position fixing jig 30 installed above the mold 20. The method for fixing the endpoint detection window member 10 to the position fixing jig 30 is not particularly limited, but for example, the endpoint detection window member 10 may be suspended and fixed by adhering the surface of the end opposite the convex shape of the endpoint detection window member 10 to the position fixing jig 30 with an adhesive or double-sided tape, or the endpoint detection window member 10 may be suspended and fixed by being clamped by clamping portions 31 of the position fixing jig 30.

[0033] For example, when the end point detection window members 10 are fixed to the bottom surface of the mold 20, it is difficult to change the number or position of the end point detection window members 10 after the mold is filled with curable resin. On the other hand, when the end point detection window members 10 are fixed by hanging as in this embodiment, it is easy to change the position or number of the end point detection window members 10 even after the mold 20 has been filled with curable resin but before it has hardened.

[0034] Furthermore, there is no need to make any other modifications to the mold itself, such as the bottom of the mold 20, in order to fix the end point detection window member 10, and the mold 20 can be the same as the one used to manufacture polishing pads that do not have an end point detection window.

[0035] The clamping portion 31 is not particularly limited as long as it clamps and fixes the end point detection window member 10 as described above, and may have one or more members that clamp the end point detection window member 10, and may further have an adjustment portion 32 for adjusting the clamping force.

[0036] Such an adjustment unit 32 may be, for example, a screw or a spring that tightens a plurality of members (clamping units 31) that clamp the endpoint detection window member 10, as shown in Figures 3 and 4. In Figure 3, the clamping units 31, which are made up of two members, are connected via the adjustment unit 32 (screw), and the adjustment unit 32 can adjust the distance between the clamping units 31, which are made up of two members. As a result, by tightening the clamping units 31 with the adjustment unit 32 to shorten the distance between the clamping units 31, the side surfaces of the endpoint detection window member 10 are pressed down, and the clamping force is adjusted. Also, in Figure 4, the clamping units 31 have the adjustment unit 32 (screw), and the adjustment unit 32 (screw) can directly clamp and fix the endpoint detection window member 10.

[0037] 5 and 6 show top views of a mold 20 for producing a resin sheet, and Fig. 7 shows a cross-sectional view taken along line A-A' in Fig. 5 before a curable resin is poured into the mold 20. The mold 20 shown in Figs. 5 to 7 includes a position fixing jig 30 that fixes the endpoint detection window member 10 of the embodiment shown in Fig. 2 using an adjustment unit 32 of the embodiment shown in Fig. 4. As shown in Figs. 5 and 7, the position fixing jig 30 is installed above the mold 20, and the endpoint detection window member 10 is clamped by clamping units 31 of the position fixing jig 30, thereby being suspended and fixed vertically downward.

[0038] The shape of the mold 20 is not particularly limited, but may be, for example, a flat mold for forming a resin sheet, or a rectangular mold for forming a resin block for cutting out a resin sheet. The position fixing jig 30 is fixed in contact with the side wall 22 so as to cover the upper part of the mold 20.

[0039] The location of the position fixing jig 30 that comes into contact with the mold 20 may have an uneven shape (first fitting portion) that can fit with the upper part of the mold 20. Furthermore, the location of the mold 20 that comes into contact with the position fixing jig 30 may also have an uneven shape (second fitting portion) that can fit with the position fixing jig 30. This makes it easier to position the position fixing jig 30 when installing it on the mold 20, and tends to prevent the embedded position of the endpoint detection window member 10 from shifting during each curing process.

[0040] Furthermore, the position fixing jig 30 may have a positioning portion that positions and fixes the end-point detection window member 10. Here, the positioning portion can have an uneven shape that is formed at the location where the position fixing jig 30 and the pedestal portion 12 come into contact with each other, allowing the position fixing jig 30 and the pedestal portion 12 to fit together. This tends to prevent the embedded position of the end-point detection window member 10 from shifting during each curing process.

[0041] The material of the position fixing jig 30 is not particularly limited, but may be a heat-resistant material that is not deformed by the heat of the hardening process, such as aluminum alloy or stainless steel.

[0042] 1.2.2.Curing resin In the curing step, the endpoint detection window member 10 is fixed in the mold 20 as described above, and the curable resin 40 is cured while in contact with the endpoint detection window member 10 to form a resin sheet 50 incorporating the endpoint detection window member 10 (endpoint detection window 51). Figure 8 shows a cross-sectional view taken along line A-A' in Figure 5 after the curable resin has been injected into the mold 20.

[0043] In this embodiment, the manner in which the curable resin 40 is cured while in contact with the end point detection window member 10 is not particularly limited, and the end point detection window member 10 may be fixed in the mold 20 as shown in Figure 5, and then the mold 20 may be filled with the curable resin 40 and the curable resin 40 may be cured, or the mold 20 may be filled with the curable resin 40, and then the end point detection window member 10 may be brought into contact with the curable resin, and then the curable resin 40 may be cured.

[0044] The curable resin is not particularly limited, but examples thereof include polyester-based polyurethane resins, polyether-based polyurethane resins, and polycarbonate-based polyurethane resins. These may be used alone or in combination of two or more. Such polyurethane resins can be synthesized from polyisocyanate and polyol.

[0045] 1.3.Slicing process The slicing step is a step of slicing the resin sheet to form a polishing layer. Figures 9 and 10 show a top view and a cross-sectional view of the resin sheet 50 obtained after the curing step, by removing it from the mold 20 and removing the base portion 12. As shown in Figures 9 and 10, the resin sheet has an endpoint detection window member embedded therein.

[0046] The slicing method is not particularly limited, but for example, a resin sheet as shown in Figures 9 and 10 may be cut in the surface direction to form a polishing pad of any thickness. Also, a rectangular polishing pad may be cut into a circular shape as shown in Figure 11.

[0047] 1.4.Groove formation process The method for manufacturing a polishing pad of this embodiment may optionally include a groove forming step of forming grooves on the polishing surface of the polishing layer (see FIG. 12). Note that it is preferable not to perform groove processing on the exposed portion of the end-point detection window member, as this would interfere with optical end-point detection.

[0048] 1.5.Other processes The method for producing a polishing pad of this embodiment may optionally include a lamination step of laminating a base layer and / or a cushion layer on the surface of the polishing layer opposite the polishing surface.

[0049] 2. Polishing pad Fig. 11 shows a schematic perspective view of the polishing pad of this embodiment, and Fig. 12 shows a cross-sectional view of the periphery of the endpoint detection window 51 in Fig. 11. As shown in Fig. 12, the polishing pad of this embodiment has a resin sheet 50 (polishing layer) and an endpoint detection window 51, and may have a cushion layer 52 on the side opposite to the polishing surface 50a, as necessary.

[0050] As shown in Fig. 12, an adhesive layer 53 may be provided between the resin sheet 50 (polishing layer) and the cushion layer 52, and an adhesive layer 54 may be provided on the surface of the cushion layer 52. The polishing surface 50a of the polishing pad of this embodiment may be flat, or may have an uneven surface with grooves 55 formed therein, as shown in Fig. 12. The grooves 55 may be formed by using a plurality of grooves of various shapes, such as concentric circles, a lattice pattern, or a radial pattern, either alone or in combination.

[0051] The end point detection window 51 is a transparent member provided in an opening in the resin sheet 50 (polishing layer), and serves as a transmission path for light from the film thickness detection sensor in optical end point detection. In this embodiment, the end point detection window is circular, but may be square, rectangular, polygonal, elliptical, or other shapes as needed.

[0052] The resin sheet 50 (polishing layer) is not particularly limited, but may be, for example, a polyurethane sheet. This polyurethane sheet has an opening in which an end-point detection window is embedded. The location of the opening is not particularly limited, but it is preferable to provide it at a radial position corresponding to a film thickness detection sensor installed on the table of the polishing apparatus. Furthermore, the number of openings is not particularly limited, but it is preferable to have multiple openings at similar radial positions so that the window passes over the film thickness detection sensor multiple times during one rotation of the polishing pad attached to the table. [Industrial Applicability]

[0053] The method for producing a polishing pad of the present invention has industrial applicability as an efficient method for producing a polishing pad suitable for an optical endpoint detection method. [Explanation of symbols]

[0054] 10...End point detection window member, 11...Columnar portion, 12...Pedestal portion, 20...Mold, 21...Bottom surface, 22...Side wall, 30...Position fixing jig, 31...Clip portion, 32...Adjustment portion, 40...Hardening resin, 50...Resin sheet, 50a...Polished surface, 51...End point detection window, 52...Cushion layer, 53...Adhesive layer, 54...Adhesive layer, 55...Groove

Claims

1. A method for manufacturing a polishing pad having a polishing layer with an endpoint detection window, comprising: a curing step of fixing an end point detection window member in a mold and curing the curable resin in contact with the end point detection window member to form a resin sheet incorporating the end point detection window member; a slicing step of slicing the resin sheet to form an abrasive layer, In the curing step, the end-point detection window member is suspended and fixed by a position fixing jig installed on an upper portion of the mold, When the end point detection window member is suspended and fixed, the lower end of the end point detection window member has a convex shape, The convex shape is a surface that is higher from the end toward an arbitrary portion. A method for manufacturing a polishing pad.

2. In the curing step, after filling the mold with a curable resin, the end-point detection window member is brought into contact with the curable resin to cure the curable resin. The method for producing the polishing pad according to claim 1 .

3. In the curing step, the end point detection window member is fixed in the mold, and then a curable resin is filled in the mold and cured. The method for producing the polishing pad according to claim 1 .

4. The method further includes a window member forming step of forming the end point detection window member, at least one end of which has the convex shape. The method for producing a polishing pad according to any one of claims 1 to 3.

5. The length L of the portion of the end-point detection window member having the convex shape is 3.0 to 20 mm. The method for producing the polishing pad according to any one of claims 1 to 4.

6. the ratio (L / S) of the length L of the portion of the end-point detection window member having the convex shape to the horizontal cross-sectional area S of the end-point detection window member is 0.002 to 0.4; The method for producing the polishing pad according to any one of claims 1 to 5.

7. The length L of the portion of the end point detection window member having the convex shape is 0.03 to 0.30Lw with respect to the total length Lw of the end point detection window member. The method for producing the polishing pad according to any one of claims 1 to 6.

8. the position fixing jig has a first fitting portion that fits with the upper part of the mold; The method for producing the polishing pad according to any one of claims 1 to 7.

9. the mold has a second fitting portion that fits with the position fixing jig; The method for producing a polishing pad according to any one of claims 1 to 8.

10. The position fixing jig has a positioning portion that positions and fixes the end point detection window member. The method for producing a polishing pad according to any one of claims 1 to 9.

11. a groove forming step of forming grooves on the polishing surface of the polishing layer, No groove processing is performed on the exposed portion of the end point detection window member before the groove forming step. The method for producing a polishing pad according to any one of claims 1 to 10.

12. a lamination step of laminating a base layer and / or a cushion layer on the surface of the polishing layer opposite to the polishing surface, The method for producing a polishing pad according to any one of claims 1 to 11.

Images