Polishing pad and method of manufacturing a polishing pad

Abstract

According to the present application, there are provided a polishing pad capable of suppressing unevenness in light transmittance or a polishing pad capable of reducing adhesion or fixation of polishing debris to the surface of the side of the polishing surface of a light-transmissive resin member (window member).

Description

Technical Field

[0001] This invention relates to an abrasive pad and a method for manufacturing the same, and more particularly to an abrasive pad for chemical mechanical polishing (CMP) with a light-transmitting region and a method for manufacturing the same. More specifically, it relates to an abrasive pad having an endpoint detection window capable of optically detecting the endpoint of the polishing process. Background Technology

[0002] Chemical mechanical polishing (CMP) is used in semiconductor manufacturing processes, especially in multilayer wiring formation processes such as planarization of interlayer insulating films, metal plug formation, and embedded wiring. CMP is a technique that uses a slurry containing dispersed abrasive particles to polish a wafer while pressing the surface to be polished against the polishing surface of a polishing pad. CMP polishing pads are broadly classified into hard polishing pads and soft polishing pads. For hard polishing pads, the dry molding method, which involves casting a curable composition containing a urethane prepolymer into a mold and allowing it to cure, is the mainstream method. For soft polishing pads, the wet film formation method, which uses a coagulation bath to form a film of urethane resin and then dries it, is the mainstream method. In recent years, with the increasing demand for low defect rates and high surface roughness elimination in polished materials, the use of soft polishing pads in fine polishing processes has become more common.

[0003] In recent years, the rapid development of multilayer and high-precision semiconductor devices has demanded further improvements in yield and production volume. For polishing pads, high planarity without defects and dishing is desired. To meet these requirements for high-precision CMP, it is necessary to determine the polishing endpoint and detect the moment when the desired surface characteristics and planarity are achieved. Endpoint detection based on optical measurements has been used in the past. Summary of the Invention

[0004] Optical measurement is a method of observing the wafer surface through a measurement window set on a polishing pad. When the measurement window is placed on the polishing pad for optical measurement, the polishing pad is usually opaque, so a transparent material of a different material than the polishing pad needs to be placed in the area that becomes the window. If the surface of this transparent material is scratched during polishing, or if condensation occurs on the back of the transparent material due to slurry leakage from the gap between the polishing area and the transparent material, light transmittance will decrease due to various factors. Therefore, it is difficult to maintain high accuracy in determining the polishing endpoint from the beginning to the end of polishing. Furthermore, when using a soft polishing pad in processes such as fine polishing, if the polishing pad is pressed against the wafer, the window will protrude from the polishing surface. This protruding window, which has no polishing capability, may touch the wafer, potentially causing polishing scratches.

[0005] As a polishing pad for solving the problem of reduced light transmittance, Japanese Patent Application Publication No. 2008-221367 (Patent Document 1) discloses a polishing pad that prevents moisture from the slurry from condensing on the back side of the light transmittance area by hydrophilizing the back side of the light transmittance area, even when the slurry leaks from the joint between the polishing area and the light transmittance area to the back side of the light transmittance area, thus preventing a decrease in light transmittance.

[0006] Similarly, Japanese Patent Application Publication No. 2004-343090 (Patent Document 2) discloses an abrasive pad that uses a light-curing adhesive to bond and fix the light-transmitting area to the inner wall of a through hole provided in the abrasive substrate, thereby preventing the slurry from leaking out of the gap during abrasion.

[0007] Japanese Patent No. 4931133 (Patent Document 3) discloses an abrasive pad that pre-roughens the surface of the abrasive surface side of the light-transmitting area by performing surface roughening treatment such as sandblasting, thereby preventing end-point detection errors caused by the decrease in light transmittance from the beginning to the end of the abrasive process.

[0008] In addition, as a polishing pad to improve the scratch problem, Japanese Patent Application Publication No. 2014-104521 (Patent Document 4) proposes a polishing pad that has a recess by making the window surface lower than the polishing surface of the polishing layer, so that the window does not touch the wafer, thereby preventing the window surface from being scratched or reducing polishing scratches on the wafer.

[0009] However, the abrasive pads in Patent Documents 1 and 2 focus on solving the problem of condensation caused by leakage on the sides and back of the light-transmitting component, and do not address the uneven light transmittance caused by the presence of slurry on the surface of the light-transmitting component.

[0010] Similarly, the abrasive pad in Patent Document 3 does not address the uneven light transmittance caused by the presence of slurry on the surface of the light-transmitting component. Furthermore, the abrasive pad in Patent Document 3 roughens the window surface, making it inherently difficult to achieve high light transmittance. Moreover, the varying surface roughness caused by the slurry, abrasive particles, and dressing during abrasion makes it difficult to maintain a constant light transmittance.

[0011] Because the abrasive pad in Patent Document 4 has a recess, most of the slurry entering the recess moves to the side of the recess due to centrifugal force and is then discharged from the groove provided on the abrasive surface. Especially when applied to a soft abrasive pad, slurry flow caused by the soft abrasive layer is likely to occur. When light is irradiated onto a light-transmitting component, there are instances where slurry is present on the surface of the light-transmitting component and instances where slurry is not present. However, cited document 4 does not recognize this problem, nor does it mention how to solve it.

[0012] The invention in the first aspect is made in view of the above, and its object is to provide an abrasive pad that can suppress the unevenness of light transmittance caused by the presence of slurry on the surface of a light-transmitting component.

[0013] The inventors discovered that the light transmittance differs when a slurry is present on the surface of a light-transmitting component and when no slurry is present. This results in uneven light transmittance, making it difficult to determine the grinding endpoint with high precision. This problem was solved by reducing the water contact angle on the surface of the grinding side of the light-transmitting component, thus completing the first aspect of the present invention.

[0014] Furthermore, optical measurement is a method of observing the surface of a wafer by means of a measurement window provided on a polishing pad. When a measurement window is provided on a polishing pad for optical measurement, the polishing pad is usually opaque, so a transparent material of a different material than the polishing pad needs to be placed in the area that becomes the window. If the surface of this transparent material is scratched during polishing, or if slurry leaks from the gap between the polishing area and the transparent material, causing condensation on the back of the transparent material, light transmittance will decrease due to various factors. Therefore, it is difficult to maintain high accuracy in determining the polishing endpoint from the beginning to the end of polishing. Additionally, when using a soft polishing pad in processes such as fine polishing, if the polishing pad is pressed against the wafer, the window will protrude from the polishing surface. This protruding window, which has no polishing capability, may touch the wafer, potentially causing polishing scratches.

[0015] As a polishing pad for solving the problem of reduced light transmittance, Japanese Patent Application Publication No. 2008-221367 (Patent Document 1) discloses a polishing pad that prevents moisture from the slurry from condensing on the back side of the light transmittance area by hydrophilizing the back side of the light transmittance area, even if the slurry leaks from the joint between the polishing area and the light transmittance area to the back side of the light transmittance area, thereby preventing a decrease in light transmittance.

[0016] In addition, in Japanese Patent Application Publication No. 2003-285257 (Patent Document 5), an abrasive pad was proposed to solve the problem of surface roughening, light scattering and reduced light transmittance of window components caused by slurry. The abrasive pad was designed to make the surface of window components made of inorganic transparent materials such as glass water-repellent.

[0017] Furthermore, in Japanese Patent Application Publication No. 2004-327974 (Patent Document 6), as a grinding pad to solve the problem of reduced grinding performance due to the lack of slurry retention and discharge capacity of window components, a grinding pad containing water-soluble substances dispersed in the matrix material constituting the window was proposed.

[0018] However, the abrasive pad in Patent Document 1 focuses on solving the problem of condensation caused by leakage on the back of the light-transmitting component, and does not address the uneven light transmittance caused by the presence of slurry on the surface of the light-transmitting component.

[0019] The abrasive pad in Patent Document 5 addresses the reduction in light transmittance caused by roughening of the window component surface through abrasion with slurry, and uses glass as the window component. Since the window component is harder than the abrasive layer, it is positioned such that its surface is lower than the abrasive layer surface. This leads to slurry easily becoming trapped between the window component surface and the surface of the object being abraded. To remove this slurry, the window component surface is made water-repellent. However, during abrasion with continuous supply of abrasive slurry, it is difficult to completely remove all the slurry present on the surface of the light-transmitting component. Small amounts of slurry, due to water repellency, form droplets, potentially causing uneven light transmittance.

[0020] Patent Document 6's abrasive pad disperses a water-soluble substance within the matrix constituting the window. During use, the water-soluble substance comes into contact with water and becomes free, forming pores to retain the slurry, thus achieving slurry retention and discharge capabilities. This is predicated on the dispersion of the water-soluble substance throughout the matrix material. Like Patent Document 1, Patent Document 6 does not address the uneven light transmittance caused by the presence of slurry on the surface of the translucent component. Furthermore, when a hydrophilic substance is incorporated into the matrix material using the method of Patent Document 6, the matrix material and the hydrophilic substance are mixed, making the entire window hydrophilic. Therefore, the window may expand, deform, peel off from the abrasive area, or leak slurry due to the presence of the slurry.

[0021] The second aspect of the present invention is made in view of the above, and its object is to provide an abrasive pad that can suppress the unevenness of light transmittance caused by the presence of slurry on the surface of a light-transmitting component.

[0022] The inventors discovered that the light transmittance differs when a slurry is present on the surface of a light-transmitting component and when no slurry is present. This results in uneven light transmittance, making it difficult to determine the grinding endpoint with high precision. The inventors solved this problem by coating the surface of the light-transmitting component with a hydrophilic resin, thus completing the second aspect of the present invention.

[0023] Furthermore, optical measurement is a method of observing the surface of a wafer by means of a measurement window provided on a polishing pad. When a measurement window is provided on a polishing pad for optical measurement, the polishing pad is usually opaque, so a transparent material of a different material than the polishing pad needs to be placed in the part that becomes the window. If the surface of this transparent material is scratched during polishing, or if the back of the transparent material is exposed due to leakage of slurry from the gap between the polishing area and the transparent material, light transmittance will decrease due to various factors. Therefore, it is difficult to maintain high accuracy in determining the polishing endpoint from the beginning to the end of polishing. In addition, when a soft polishing pad is used in processes such as fine polishing, if the polishing pad is pressed against the wafer, the window will protrude on the polishing surface. This protruding window, which has no polishing capability, may touch the wafer and cause polishing scratches. Furthermore, the following problem exists: polishing byproducts (polishing debris formed by the agglomeration of the polishing pad, the polished object, polishing slurry, etc.) are generated during the polishing process, which gradually adhere to and become fixed on the polishing surface of the window member, making it difficult to perform stable optical measurement.

[0024] As a pad with an endpoint detection window, Japanese Patent Application Publication No. 2014-104521 (Patent Document 4) discloses an abrasive pad in which the window member is arranged at a position that is recessed from the abrasive surface in order to suppress the generation of abrasive scratches caused by the contact between the window member and the abrasive.

[0025] In addition, Japanese Patent Application Publication No. 2008-221367 (Patent Document 1) discloses an abrasive pad that, by hydrophilizing the back side of the window component, prevents moisture from the slurry from condensing on the back side of the window component even when the slurry leaks from the joint between the abrasive area and the window component to the back side of the window component, thus preventing a decrease in light transmittance.

[0026] However, the polishing pad in Patent Document 4 suffers from a problem where the polishing shavings contained in the slurry sink into the recessed window area and adhere to the window surface, resulting in a decrease in light transmittance over time. The polishing pad in Patent Document 1 focuses on solving the problem of condensation caused by leakage to the sides and back of the window component, but it does not improve the problem of polishing shavings adhering to and adhering to the polished surface of the window component.

[0027] The third aspect of the present invention is made in view of the above, and its object is to provide an abrasive pad that can reduce the adhesion and fixation of abrasive debris to the surface of the abrasive side of a translucent resin component (window component).

[0028] The inventors have discovered that by grafting and polymerizing a hydrophilic monomer onto the surface of the polished side of a translucent resin component, the adhesion and fixation of polishing debris onto the surface of the polished side of the translucent resin component (window component) can be reduced, thereby completing the third aspect of the present invention.

[0029] Furthermore, optical measurement is a method of observing the surface of a wafer by means of a measurement window provided on a polishing pad. When the measurement window is provided on the polishing pad for optical measurement, the polishing pad is usually opaque, so a transparent material of a different material than the polishing pad needs to be placed in the portion that becomes the window. If the surface of this transparent material is scratched during polishing, the light transmittance decreases. Therefore, it is difficult to maintain high accuracy in determining the polishing endpoint from the beginning to the end of polishing. Additionally, when using a soft polishing pad in processes such as fine polishing, if the polishing pad is pressed against the wafer, the window will protrude from the polishing surface. This protruding, hard window, which lacks polishing ability, may touch the wafer, potentially causing polishing scratches.

[0030] As a pad for solving these problems, an abrasive pad with a window for endpoint detection has been proposed, in which a window member is disposed at a position that is more concave than the abrasive surface (Japanese Patent Application Publication No. 2014-104521 (Patent Document 4), Japanese Patent Application Publication No. 2002-1652 (Patent Document 7)).

[0031] However, the abrasive pad in Patent Document 4 has the problem that the abrasive slurry sinks into the recessed window area, resulting in reduced light transmittance. Although the abrasive pad in Patent Document 7 can promote the discharge of abrasive slurry from the upper surface of the light-transmitting window by setting a window groove near the light-transmitting window, it has the problem of uneven light transmittance values, making it difficult to perform accurate optical measurements.

[0032] The fourth aspect of the present invention is made in view of the above, and its object is to provide an abrasive pad capable of suppressing uneven light transmittance.

[0033] The fourth aspect of the present invention suppresses significant unevenness in light transmittance between the presence and absence of slurry on the surface of the light-transmitting resin component by applying a specific resin to the surface of the polished side of the light-transmitting resin component, thereby enabling more accurate determination of the polishing endpoint.

[0034] The present invention provides the following in the first to fourth aspects.

[0035] [1] An abrasive pad having a light-transmitting component and an abrasive layer,

[0036] The aforementioned abrasive layer has an abrasive surface for abrading the workpiece, and the aforementioned abrasive pad has a through hole extending from the abrasive surface to its opposite surface.

[0037] The aforementioned light-transmitting member is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member exists within the through-hole, and

[0038] The water contact angle of the surface of the ground surface of the above-mentioned light-transmitting component is less than 80 degrees.

[0039] [2] The abrasive pad as described in [1], wherein the water contact angle of the surface of the light-transmitting member opposite to the abrasive surface is greater than 80 degrees.

[0040] [3] An abrasive pad having a light-transmitting component and an abrasive layer,

[0041] The aforementioned abrasive layer has an abrasive surface for abrading the workpiece, and the aforementioned abrasive pad has a through hole extending from the abrasive surface to its opposite surface.

[0042] The aforementioned light-transmitting member is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member exists within the through-hole, and

[0043] The surface of the ground surface of the above-mentioned light-transmitting component is coated with a hydrophilic resin.

[0044] [4] The abrasive pad as described in [3], wherein the hydrophilic resin is a resin having ion-binding hydrophilic groups.

[0045] [5] The abrasive pad as described in [4], wherein the resin having ion-binding hydrophilic groups is a resin having ion-binding hydrophilic groups in its side chains.

[0046] [6] The abrasive pad as described in [4] or [5], wherein in the resin having an ion-binding hydrophilic group, the cationic portion of the ion-binding hydrophilic group is covalently bonded to the monomer constituting the resin, and is ionically bonded to the anionic portion of the ion-binding hydrophilic group.

[0047] [7] The abrasive pad as described in any one of [4] to [6], wherein the ion-binding hydrophilic group contains an ammonium cation.

[0048] [8] The abrasive pad as described in any one of [3] to [7], wherein the surface of the abrasive side of the translucent member coated with the above-described resin has a water contact angle of less than 50 degrees.

[0049] [9] An abrasive pad having a translucent resin component and an abrasive layer,

[0050] The aforementioned abrasive layer has an abrasive surface for abrading the workpiece, and the aforementioned abrasive pad has a through hole extending from the abrasive surface to its opposite surface.

[0051] The aforementioned light-transmitting resin component is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component exists within the through-hole, and

[0052] The aforementioned translucent resin component has hydrophilic monomers grafted onto its polished surface.

[0053]

[10] The abrasive pad as described in [9], wherein the water contact angle of the surface of the abrasive side of the above-mentioned translucent resin component is less than 80 degrees.

[0054]

[11] The abrasive pad as described in [9] or

[10] , wherein the hydrophilic monomer is an acrylic monomer.

[0055]

[12] The abrasive pad as described in

[11] , wherein the resin of the grafted surface is formed into an ionic complex by a polymer selected from polyethylene glycol, polyvinylpyrrolidone, polyxyl viologen, polyethyleneimine, polyvinylpyridine chloride and polyvinylbenzyltrimethylammonium chloride.

[0056]

[13] An abrasive pad having a translucent resin component and an abrasive layer,

[0057] The aforementioned abrasive layer has an abrasive surface for abrading the workpiece, and the aforementioned abrasive pad has a through hole extending from the abrasive surface to its opposite surface.

[0058] The aforementioned light-transmitting resin component is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component exists within the through-hole, and

[0059] The aforementioned translucent resin component has, at least on its polished surface side, a resin comprising constituent units derived from polyfunctional (meth)acrylate monomers, wherein the polyfunctional (meth)acrylate monomers have two or more polymerizable functional groups and have -C 2-4 Alkylene-O- unit.

[0060]

[14] The abrasive pad as described in

[13] , wherein the above-mentioned multifunctional (meth)acrylate monomer is at least one selected from the group consisting of:

[0061] With -C 2-4 Monomers formed by esterification of alkylene-O-unit compounds with (meth)acrylic acid; and

[0062] Bonus C 2-4 Monomers formed by esterification of teratolytic or higher alcohols of epoxides with (meth)acrylic acid.

[0063]

[15] The abrasive pad as described in

[14] , wherein the three or more alcohols are selected from the group consisting of glycerol, diglycerol, triglycerol, trimethylolpropane, di-trimethylolpropane, erythritol, pentaerythritol and dipentaerythritol.

[0064]

[16] The abrasive pad as described in any one of

[13] to

[15] , wherein the above-mentioned -C 2-4 The alkylene-O- unit is derived from ethylene oxide and / or propylene oxide.

[0065]

[17] The abrasive pad as described in any one of

[13] to

[16] , wherein the polyfunctional (meth)acrylate monomer is selected from at least one of the group consisting of polyethylene glycol diacrylate, polypropylene glycol diacrylate, ethoxylated pentaerythritol tetraacrylate, propoxylated pentaerythritol tetraacrylate, ethoxylated glycerol triacrylate, propoxylated glycerol triacrylate, ethoxylated trimethylolpropane triacrylate, and propoxylated trimethylolpropane triacrylate.

[0066]

[18] The abrasive pad as described in any one of [1] to

[17] , wherein, when the abrasive surface is set as the upper surface and the opposite surface is set as the lower surface, the surface of the abrasive surface side of the light-transmitting resin member is lower than the abrasive surface.

[0067]

[19] The abrasive pad as described in [1] to

[18] , wherein the abrasive surface has a groove, and when the abrasive surface is set as the upper surface and its opposite surface is set as the lower surface, the uppermost part of the light-transmitting member is located at the same position as or below the lowermost part of the groove.

[0068]

[20] The polishing pad as described in any one of [1] to

[19] , wherein, when the through hole of the polishing layer is designated as the first through hole, the polishing pad further comprises other layers having a second through hole, the second through hole having an equivalent circle diameter smaller than the first through hole.

[0069] The other layers mentioned above are located on the side of the polishing layer opposite to the polishing surface.

[0070] When the polishing pad is viewed from the polishing surface side along the thickness direction, the first through hole and the second through hole at least partially overlap.

[0071] The light-transmitting member is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member exists within the first through hole.

[0072] Furthermore, the present invention in the first aspect provides the following.

[0073] [1-1] An abrasive pad having a light-transmitting component and an abrasive layer,

[0074] The aforementioned abrasive layer has an abrasive surface for abrading the workpiece, and the aforementioned abrasive pad has a through hole extending from the abrasive surface to its opposite surface.

[0075] The aforementioned light-transmitting member is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member exists within the through-hole, and

[0076] The water contact angle of the surface of the ground surface of the above-mentioned light-transmitting component is less than 80 degrees.

[0077] [1-2] The abrasive pad as described in [1-1], wherein when the abrasive surface is set as the upper surface and its opposite surface is set as the lower surface, the uppermost part of the light-transmitting member is lower than the abrasive surface.

[0078] [1-3] The abrasive pad as described in [1] or [1-2], wherein the water contact angle of the surface of the light-transmitting member opposite to the abrasive surface is greater than 80 degrees.

[0079] [1-4] The abrasive pad as described in any one of [1-1] to [1-3], wherein the visible light transmittance when the light-transmitting member is irradiated with light of wavelength 380 nm to 780 nm is 60% or more.

[0080] [1-5] The abrasive pad as described in any one of [1-1] to [1-4], wherein the abrasive surface has a groove.

[0081] [1-6] The abrasive pad as described in [1-5], wherein the groove is an embossed groove.

[0082] [1-7] The abrasive pad as described in [1-5] or [1-6], wherein, when the abrasive surface is set as the upper surface and its opposite surface is set as the lower surface, the uppermost part of the light-transmitting member is located at the same position as or below the lowermost part of the groove.

[0083] [1-8] The abrasive pad as described in any one of [1-1] to [1-7], wherein the shape of the through hole is circular when viewed from the abrasive surface side of the abrasive pad along the thickness direction of the abrasive pad.

[0084] [1-9] The polishing pad as described in any one of [1-1] to [1-8], wherein, when the through-hole of the polishing layer is designated as the first through-hole, the polishing pad further comprises other layers having a second through-hole, the second through-hole having an equivalent circle diameter smaller than the first through-hole.

[0085] The other layers mentioned above are located on the side of the polishing layer opposite to the polishing surface.

[0086] When the polishing pad is viewed from the polishing surface side along the thickness direction, the first through hole and the second through hole at least partially overlap.

[0087] The light-transmitting member is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member exists within the first through hole.

[0088] [1-10] A method for manufacturing an abrasive pad according to any one of [1-1] to [1-9], comprising:

[0089] The process of preparing a polishing layer and a light-transmitting component with a water contact angle of less than 80 degrees on at least one side;

[0090] The process of setting through holes in the polishing layer; and

[0091] The process of arranging the light-transmitting member in such a way that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member is present in the through hole, wherein the light-transmitting member is arranged such that one of its surfaces becomes the grinding surface side.

[0092] Furthermore, the present invention provides the following in a second aspect.

[0093] [2-1] An abrasive pad having a light-transmitting component and an abrasive layer,

[0094] The aforementioned abrasive layer has an abrasive surface for abrading the workpiece, and the aforementioned abrasive pad has a through hole extending from the abrasive surface to its opposite surface.

[0095] The aforementioned light-transmitting member is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member exists within the through-hole, and

[0096] The surface of the ground surface of the above-mentioned light-transmitting component is coated with a hydrophilic resin.

[0097] [2-2] The abrasive pad as described in [2-1], wherein the hydrophilic resin is a resin having ion-binding hydrophilic groups.

[0098] [2-3] The abrasive pad as described in [2-2], wherein the resin having ion-binding hydrophilic groups is a resin having ion-binding hydrophilic groups in its side chains.

[0099] [2-4] The abrasive pad as described in [2-2] or [2-3], wherein in the resin having ion-binding hydrophilic groups, the cationic portion of the ion-binding hydrophilic group is covalently bonded to the monomer constituting the resin, and is ionically bonded to the anionic portion of the ion-binding hydrophilic group.

[0100] [2-5] The abrasive pad as described in any one of [2-2] to [2-4], wherein the ion-binding hydrophilic group contains an ammonium cation.

[0101] [2-6] The abrasive pad as described in any one of [2-1] to [2-5], wherein the surface of the abrasive side of the light-transmitting member coated with the above-described resin has a water contact angle of less than 50 degrees.

[0102] [2-7] The abrasive pad as described in any one of [2-1] to [2-6], wherein the abrasive surface has a groove.

[0103] [2-8] The abrasive pad as described in [2-7], wherein the groove is an embossed groove.

[0104] [2-9] The abrasive pad as described in [2-7] or [2-8], wherein, when the abrasive surface is set as the upper surface and its opposite surface is set as the lower surface, the uppermost part of the light-transmitting member coated with the resin is located at the same position as or lower than the lowermost part of the groove.

[0105] [2-10] The abrasive pad as described in any one of [2-1] to [2-9], wherein the through hole is circular when viewed from the abrasive surface side of the abrasive pad along the thickness direction of the abrasive pad.

[0106] [2-11] The polishing pad as described in any one of [2-1] to [2-10], wherein, when the through-hole of the polishing layer is designated as the first through-hole, the polishing pad further comprises other layers having a second through-hole, the second through-hole having an equivalent circle diameter smaller than the first through-hole.

[0107] The other layers mentioned above are located on the side of the polishing layer opposite to the polishing surface.

[0108] When the polishing pad is viewed from the polishing surface side along the thickness direction, the first through hole and the second through hole at least partially overlap.

[0109] The light-transmitting member is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member exists within the first through hole.

[0110] [2-12] A method for manufacturing an abrasive pad according to any one of [2-1] to [2-11], comprising:

[0111] The process of preparing a translucent component with at least one side coated with a hydrophilic resin and a polishing layer;

[0112] The process of setting through holes in the polishing layer; and

[0113] When viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the process of arranging the light-transmitting member in such a way that the light-transmitting member exists in the through hole is such that the coating surface of the light-transmitting member is the grinding surface side.

[0114] Furthermore, the present invention provides the following in a third aspect.

[0115] [3-1] An abrasive pad having a translucent resin component and an abrasive layer,

[0116] The aforementioned abrasive layer has an abrasive surface for abrading the workpiece, and the aforementioned abrasive pad has a through hole extending from the abrasive surface to its opposite surface.

[0117] The aforementioned light-transmitting resin component is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component exists within the through-hole, and

[0118] The aforementioned translucent resin component has hydrophilic monomers grafted onto its polished surface.

[0119] [3-2] The abrasive pad as described in [3-1], wherein the water contact angle of the surface of the abrasive side of the above-mentioned translucent resin component is less than 80 degrees.

[0120] [3-3] The abrasive pad as described in [1] or [2], wherein the hydrophilic monomer is an acrylic monomer.

[0121] [3-4] The abrasive pad as described in [3-3], wherein the resin of the grafted surface is formed into an ionic complex by a polymer selected from polyethylene glycol, polyvinylpyrrolidone, polyxylvioletin, polyethyleneimine and polyvinyl chloride pyridine to form a complex.

[0122] [3-5] The abrasive pad as described in any one of [3-1] to [3-4], wherein, when the abrasive surface is set as the upper surface and its opposite surface is set as the lower surface, the grafted surface of the light-transmitting resin member is lower than the abrasive surface.

[0123] [3-6] The abrasive pad as described in any one of [3-1] to [3-5], wherein the abrasive surface has a groove.

[0124] [3-7] The abrasive pad as described in [3-6], wherein the groove is an embossed groove.

[0125] [3-8] The abrasive pad as described in [3-6] or [3-7], wherein, when the abrasive surface is set as the upper surface and its opposite surface is set as the lower surface, the grafted surface of the light-transmitting resin member is located at the same position as or below the lowest part of the groove.

[0126] [3-9] The abrasive pad as described in any one of [3-1] to [3-8], wherein the shape of the through hole is circular when viewed from the abrasive surface side of the abrasive pad along the thickness direction of the abrasive pad.

[0127] [3-10] The polishing pad as described in any one of [3-1] to [3-9], wherein, when the through-hole of the polishing layer is designated as the first through-hole, the polishing pad further comprises other layers having a second through-hole, the second through-hole having an equivalent circle diameter smaller than the first through-hole.

[0128] The other layers mentioned above are located on the side of the polishing layer opposite to the polishing surface.

[0129] When the polishing pad is viewed from the polishing surface side along the thickness direction, the first through hole and the second through hole at least partially overlap.

[0130] The light-transmitting resin component is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component exists within the first through hole.

[0131] [3-11] A method for manufacturing an abrasive pad according to any one of [3-1] to [3-10], comprising:

[0132] The process of preparing a polishing layer and a transparent resin component grafted with a hydrophilic monomer on at least one surface;

[0133] The process of setting through holes in the polishing layer; and

[0134] The process of arranging the light-transmitting resin component in such a way that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component is present in the through hole, wherein the grafted surface of the light-transmitting resin component is arranged to be the grinding surface side.

[0135] [3-12] The manufacturing method as described in [3-11] further includes a step of performing plasma grafting treatment on at least one surface of the above-mentioned translucent resin component.

[0136] Furthermore, the present invention provides the following in a fourth aspect.

[0137] [4-1] An abrasive pad having a translucent resin component and an abrasive layer,

[0138] The aforementioned abrasive layer has an abrasive surface for abrading the workpiece, and the aforementioned abrasive pad has a through hole extending from the abrasive surface to its opposite surface.

[0139] The aforementioned light-transmitting resin component is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component exists within the through-hole, and

[0140] The aforementioned translucent resin component has, at least on its polished surface side, a resin comprising constituent units derived from polyfunctional (meth)acrylate monomers, wherein the polyfunctional (meth)acrylate monomers have two or more polymerizable functional groups and have -C 2-4 Alkylene-O- unit.

[0141] [4-2] The abrasive pad as described in [4-1], wherein the above-mentioned multifunctional (meth)acrylate monomer is at least one selected from the group consisting of:

[0142] With -C 2-4 Monomers formed by esterification of alkylene-O-unit compounds with (meth)acrylic acid; and

[0143] Bonus C 2-4 Monomers formed by esterification of teratolytic or higher alcohols of epoxides with (meth)acrylic acid.

[0144] [4-3] The abrasive pad as described in [4-2], wherein the three or more alcohols are selected from the group consisting of glycerol, diglycerol, triglycerol, trimethylolpropane, di-trimethylolpropane, erythritol, pentaerythritol and dipentaerythritol.

[0145] [4-4] The abrasive pad as described in any one of [4-1] to [4-3], wherein the above-mentioned -C 2-4 The alkylene-O- unit is derived from ethylene oxide and / or propylene oxide.

[0146] [4-5] The abrasive pad as described in any one of [4-1] to [4-4], wherein the aforementioned polyfunctional (meth)acrylate monomer is at least one selected from the group consisting of polyethylene glycol diacrylate, polypropylene glycol diacrylate, ethoxylated pentaerythritol tetraacrylate, propoxylated pentaerythritol tetraacrylate, ethoxylated glycerol triacrylate, propoxylated glycerol triacrylate, ethoxylated trimethylolpropane triacrylate, and propoxylated trimethylolpropane triacrylate.

[0147] [4-6] The abrasive pad as described in any one of [4-1] to [4-5], wherein, when the abrasive surface is set as the upper surface and its opposite surface is set as the lower surface, the surface of the abrasive surface side of the light-transmitting resin member is lower than the abrasive surface.

[0148] [4-7] The abrasive pad as described in any one of [4-1] to [4-6], wherein the abrasive surface has grooves.

[0149] [4-8] The abrasive pad as described in [4-7], wherein the groove is an embossed groove.

[0150] [4-9] The abrasive pad as described in [4-7] or [4-8], wherein, when the abrasive surface is set as the upper surface and its opposite surface is set as the lower surface, the surface of the abrasive surface side of the light-transmitting resin member is located at the same position as or higher than the lowest part of the groove.

[0151] [4-10] The abrasive pad as described in any one of [4-1] to [4-9], wherein the shape of the through hole is circular when viewed from the abrasive surface side of the abrasive pad along the thickness direction of the abrasive pad.

[0152] [4-11] The polishing pad as described in any one of [4-1] to [4-10], wherein, when the through-hole of the polishing layer is designated as the first through-hole, the polishing pad further comprises other layers having a second through-hole, the second through-hole having an equivalent circle diameter smaller than the first through-hole.

[0153] The other layers mentioned above are located on the side of the polishing layer opposite to the polishing surface.

[0154] When the polishing pad is viewed from the polishing surface side along the thickness direction, the first through hole and the second through hole at least partially overlap.

[0155] The light-transmitting resin component is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component exists within the first through hole.

[0156] [4-12] A method for manufacturing an abrasive pad as described in any one of [4-1] to [4-11], comprising:

[0157] The process of preparing a polishing layer and a translucent resin component having resin on at least one surface, wherein the resin comprises constituent units derived from a polyfunctional (meth)acrylate monomer, the polyfunctional (meth)acrylate monomer having two or more polymerizable functional groups and having -C 2-4 alkylene-O-unit;

[0158] The process of setting through holes in the polishing layer; and

[0159] The process of arranging the light-transmitting resin component in such a way that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component is present in a through hole, wherein the surface of the light-transmitting resin component having resin containing constituent units from the polyfunctional (meth)acrylate monomer is arranged such that the grinding surface side is the surface of the light-transmitting resin component.

[0160] Invention Effects

[0161] According to a first aspect of the present invention, an abrasive pad capable of suppressing uneven light transmittance can be provided. This enables high-precision determination of the abrasive endpoint.

[0162] According to a second aspect of the present invention, an abrasive pad capable of suppressing uneven light transmittance can be provided. This enables high-precision determination of the abrasive endpoint.

[0163] According to a third aspect of the present invention, an abrasive pad capable of reducing the adhesion and fixation of abrasive debris to the abrasive surface of a light-transmitting resin component (window component) can be provided. This enables stable light detection.

[0164] According to a fourth aspect of the present invention, an abrasive pad capable of suppressing uneven light transmittance can be provided. This enables high-precision determination of the abrasive endpoint. Attached Figure Description

[0165] [ Figure 1 ] Figure 1 This is a perspective view of the abrasive surface of an abrasive pad according to one aspect of the present invention, viewed along the thickness direction.

[0166] [ Figure 2A ] Figure 2A This is a cross-sectional view (cut-off end face) of the grinding pad in the thickness direction according to one aspect of the present invention.

[0167] [ Figure 2B ] Figure 2B This is a cross-sectional view (cut-off end face) of the grinding pad in the thickness direction according to one aspect of the present invention.

[0168] [ Figure 3A ] Figure 3A This is a cross-sectional view (cut-off end face) of the grinding pad in the thickness direction according to one aspect of the present invention.

[0169] [ Figure 3B ] Figure 3B This is a cross-sectional view (cut-off end face) of the grinding pad in the thickness direction according to one aspect of the present invention.

[0170] [ Figure 4A ] Figure 4A This is a cross-sectional view (cut-off end face) of the grinding pad in the thickness direction according to one aspect of the present invention.

[0171] [ Figure 4B ] Figure 4B This is a cross-sectional view (cut-off end face) of the grinding pad in the thickness direction according to one aspect of the present invention.

[0172] [ Figure 4C ] Figure 4C This is a cross-sectional view (cut-off end face) of the grinding pad in the thickness direction according to one aspect of the present invention.

[0173] [ Figure 5A ] Figure 5A This is a cross-sectional view (cut-off end face) of the grinding pad in the thickness direction according to one aspect of the present invention.

[0174] [ Figure 5B ] Figure 5B This is a cross-sectional view (cut-off end face) of the grinding pad in the thickness direction according to one aspect of the present invention.

[0175] [ Figure 6A ] Figure 6A This is a cross-sectional view (cut-off end face) of the grinding pad in the thickness direction according to one aspect of the present invention.

[0176] [ Figure 6B ] Figure 6B This is a cross-sectional view (cut-off end face) of the grinding pad in the thickness direction according to one aspect of the present invention. Detailed Implementation

[0177] The embodiments of the present invention will be described below.

[0178] <<First-Type Abrasive Pad>>

[0179] The first aspect of the present invention is an abrasive pad having a light-transmitting member and an abrasive layer, wherein the abrasive layer has an abrasive surface for abrading the workpiece, the abrasive pad has a through hole extending from the abrasive surface to its opposite surface, the light-transmitting member is arranged such that when viewed from the abrasive surface side of the abrasive pad along the thickness direction of the abrasive pad, the light-transmitting member exists within the through hole, and the water contact angle of the surface of the abrasive surface side of the light-transmitting member is 80 degrees or less.

[0180] Within the scope of this specification and claims, a polishing layer refers to a layer having a surface (polishing surface) that contacts and polishes a workpiece such as a semiconductor device during polishing. The workpiece is not particularly limited; examples include substrates containing multiple memory dies or processor dies, test substrates, bare substrates, and gate substrates. The substrate can be at various stages of integrated circuit manufacturing; for example, the substrate can be a bare wafer, or it can be one or more stacked layers and / or patterning layers.

[0181] <Translucent Components>

[0182] The polishing pad of the first embodiment of the present invention has a light-transmitting member, i.e., a window member. Light is irradiated onto the workpiece through the light-transmitting member, thereby enabling the detection of the moment when the workpiece reaches the desired surface characteristics and planar state. Optical endpoint detection uses visible light (white light), such as lasers or lamps.

[0183] The light-transmitting member is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member exists within the through hole. Here, "arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member exists within the through hole" means that the light-transmitting member can be identified when viewed from the grinding surface of the grinding pad along the thickness direction. This concept includes the following cases: (1) such as Figure 2A , Figure 3A As shown, the light-transmitting component is connected (or bonded) to the side (sidewall) of the through hole provided in the polishing layer; (2) as Figure 4A As shown, another layer with through holes is provided below the polishing layer. The through holes have an equivalent circle diameter smaller than that of the through holes in the polishing layer. A light-transmitting member is disposed on the exposed portion 7 caused by the size difference between the through holes in the polishing layer and the through holes in the other layer; (3) as Figure 5A As shown, the light-transmitting component is sandwiched between the polished layer and other layers, arranged such that a portion of the light-transmitting component is exposed within the through-hole; (4) as Figure 6A As shown, through holes are provided in both the polishing layer and the other layer, and the light-transmitting member is arranged in such a way that it is in contact (or bonded) with the side of the through hole of either or both of them. Preferably, it is (1), (2) or (4), more preferably (1) or (2), and even more preferably (2).

[0184] As a light-transmitting component, a transparent resin component is preferred. There are no particular limitations on the transparent resin component as long as it has a degree of transparency that allows light to pass through. For example, thermosetting resins such as polyurethane resin, polyester resin, phenolic resin, urea resin, melamine resin, epoxy resin, and acrylic resin can be used; thermoplastic resins such as polyurethane resin, polyester resin, polyamide resin, cellulose resin, acrylic resin, polycarbonate resin, halogen resin (polyvinyl chloride, polytetrafluoroethylene, polyvinylidene fluoride, etc.), polystyrene resin, and olefin resin (polyethylene, polypropylene, etc.); rubbers such as butadiene rubber and isoprene rubber; photocurable resins that are cured by ultraviolet light, electron beams, or other light; and photosensitive resins, etc. Among these, acrylic resins, polyurethane resins, polyester resins, and polystyrene resins are preferred, and acrylic resins are more preferred.

[0185] The surface of the light-transmitting component preferably undergoes a hydrophilic treatment on the polished side. Not only the polished side, but also the opposite side (back side) and side surface can be hydrophilicated. However, hydrophilicating the back and side surfaces would increase costs. Furthermore, hydrophilicating the back and side surfaces is irrelevant to the effectiveness of this invention; therefore, it is preferable that only the polished side surface is hydrophilicated. By hydrophilicating the polished side surface, a light-transmitting component with a water contact angle of 80 degrees or less on the polished side surface can be easily obtained.

[0186] Examples of hydrophilic treatment methods include: physicochemical treatments such as plasma treatment and ultraviolet irradiation treatment; mechanical treatments such as roller blasting and embossing; and chemical treatments such as chemical reagent treatment and surface grafting treatment. Among these, plasma treatment or roller blasting treatment is preferred, and plasma treatment is more preferred.

[0187] Plasma treatment refers to the process of using a high-voltage power supply to strike the surface of a material with a plasma beam emitted from rods called electrodes. On the material's surface, ions and electrons emitted by the beam break the chemical bonds of the molecules on the resin surface, generating hydrophilic functional groups (OH (hydroxyl), CO (carbonyl), COOH (carboxyl), etc.) depending on the type of resin.

[0188] Roller blasting refers to a surface modification process in which a roller coated with abrasive particles is rotated at high speed.

[0189] In the first embodiment of the abrasive pad of the present invention, when the abrasive surface is set as the upper surface and its opposite surface is set as the lower surface, the uppermost part of the light-transmitting member can be at the same height as the abrasive surface, or it can be lower than the abrasive surface, preferably lower than the abrasive surface. Figure 2ABy ensuring the top of the light-transmitting component is lower than the grinding surface, it prevents grinding scratches caused by the harder light-transmitting component compared to the grinding layer. However, if the top of the light-transmitting component is lower than the grinding surface, the slurry enters the recess formed by the light-transmitting component and the side of the through-hole. Most of it will move to the side of the through-hole due to centrifugal force and be discharged through the groove. This can easily result in either a small amount of slurry remaining on the surface of the light-transmitting component or none remaining. However, when using conventional grinding pads, the light transmittance differs between cases with a small amount of slurry remaining and cases without residue, making it difficult to accurately determine the grinding endpoint. In contrast, the grinding pad of the first aspect of the present invention improves the affinity with the slurry by making the surface of the light-transmitting member hydrophilic. Even in the presence of a small amount of slurry, it spreads evenly on the window surface, thereby reducing the variation in light transmittance from the beginning to the end of the grinding process. Even if the uppermost part of the light-transmitting member is in a position lower than the grinding surface, especially if the uppermost part 4' of the light-transmitting member is in the same position as or lower than the lowermost part 8' of the groove, the grinding endpoint can be determined with high accuracy.

[0190] (Water contact angle)

[0191] In the polishing pad of the first embodiment of the present invention, the water contact angle of the surface of the polishing side of the light-transmitting member is 80 degrees or less. The water contact angle is preferably 5 to 80 degrees, more preferably 5 to 50 degrees, even more preferably 5 to 30 degrees, and even more preferably 5 to 20 degrees. If the water contact angle is within the above range, uneven light transmittance caused by the presence of slurry on the surface of the light-transmitting member can be suppressed. Therefore, more precise determination of the polishing endpoint is possible.

[0192] Conventional polishing pads typically use window components with a water contact angle greater than 80 degrees. When using windows with a hydrophilicity of less than 80 degrees, the slurry may cause the window to swell, deform, peel off from the polishing area, or leak. Therefore, window components are preferably hydrophobic with a water contact angle greater than 80 degrees. In this invention, it is preferable to hydrophilize only the surface of the polishing side to achieve a water contact angle of less than 80 degrees. In this invention, there are no particular limitations on the method for setting the water contact angle of the polishing side surface of the light-transmitting component to less than 80 degrees; however, it is preferable to use a hydrophilic treatment to set the water contact angle of the polishing side surface to less than 80 degrees. The above-described method can be cited as an example of a hydrophilic treatment method.

[0193] As a light-transmitting component, as long as the water contact angle on the polished side is below 80 degrees, there are no particular restrictions on the water contact angle on the back and sides. Therefore, the water contact angle on the back and sides can be greater than 80 degrees. That is, the back and sides of the light-transmitting component do not need to be hydrophilicated.

[0194] (Pass rate)

[0195] Regarding the abrasive pad of the first aspect of the present invention, the visible light transmittance (sometimes simply referred to as light transmittance in this specification) when the light-transmitting member is irradiated with light of wavelength from 380 nm to 780 nm is preferably 60% or more, more preferably 62% or more, even more preferably 65% ​​or more, even more preferably 70% or more, even more preferably 75% or more, even more preferably 80% or more, and even more preferably 85% or more.

[0196] Regarding the abrasive pad of the first aspect of the present invention, the light transmittance when water is attached to the surface of the light-transmitting member is preferably 60% or more, more preferably 62% or more, even more preferably 65% ​​or more, even more preferably 70% or more, even more preferably 75% or more, and even more preferably 80% or more.

[0197] Regarding the abrasive pad of the first aspect of the present invention, the light transmittance when water is not adhering to the surface of the light-transmitting member is preferably 60% or more, more preferably 62% or more, even more preferably 65% ​​or more, even more preferably 70% or more, even more preferably 75% or more, even more preferably 80% or more, and even more preferably 85% or more.

[0198] Regarding the polishing pad of the first aspect of the present invention, the difference between the light transmittance when no water adheres to the surface of the light-transmitting member and the light transmittance when water adheres to the surface of the light-transmitting member is preferably within 30%, more preferably within 20%, even more preferably within 15%, even more preferably within 10%, even more preferably within 8%, even more preferably within 6%, and even more preferably within 5%. By keeping the difference in light transmittance within the above range, it is less likely to occur a difference in light transmittance between the presence and absence of slurry on the surface of the light-transmitting member, enabling high-precision determination of the polishing endpoint.

[0199] Light transmittance can be measured using a spectrophotometer to measure the transmission spectrum from 300 to 1000 nm, and the result is obtained as the visible light transmittance (%) according to the Japanese Industrial Standard (JIS A5759:2008). Specifically, the transmittance is calculated as follows: the transmittance for each wavelength in the range of 380 to 780 nm is measured, and the transmittance at each wavelength is multiplied by a weighted average obtained from the CIE (International Commission on Illumination) daylight D65 spectral distribution, the CIE light adaptation standard relative visual sensitivity wavelength distribution, and the wavelength intervals.

[0200] In addition, regarding the determination of light transmittance when water is applied to the surface of a light-transmitting component, a sufficient amount of water (for example, about 0.01 to 0.03 mL for a light-transmitting component cut into 9 mm × 50 mm sizes) can be sprayed onto the entire surface of the polished side of the light-transmitting component. The light-transmitting component is then placed perpendicular to the ground for 60 seconds to remove the water, and the light-transmitting component obtained in this way is used for measurement.

[0201] (Through hole)

[0202] A through-hole is a hole that extends from the polishing surface to the opposite side of the polishing pad when viewed from the polishing surface side along the thickness direction of the polishing pad. The through-hole preferably penetrates the polishing layer in a manner parallel to the thickness direction or perpendicular to the polishing surface.

[0203] One through hole can be set in the polishing layer, or two or more through holes can be set separately and independently.

[0204] Examples of through-hole shapes, as seen when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, or the shapes of through-holes in the grinding surface, include: circles, ellipses, triangles, quadrilaterals, hexagons, octagons, etc. Alternatively, a shape formed by the partial overlap of multiple of the above shapes, either identical or different. Among these, a circle is particularly preferred as it does not form corners where grinding debris tends to accumulate.

[0205] (Equivalent circle diameter)

[0206] Within the scope of this specification and claims, the so-called equivalent circle diameter refers to the diameter of a perfect circle whose area is equivalent to that of the figure being measured.

[0207] The equivalent circle diameter of a through hole is the equivalent circle diameter of the through hole when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad. It is equivalent to the diameter when the shape of the through hole is circular when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad.

[0208] There is no particular limitation on the equivalent circle diameter of the through hole, but it is preferably 5 to 40 mm, more preferably 5 to 30 mm, and even more preferably 10 to 28 mm.

[0209] Furthermore, relative to the total area of ​​the grinding surface, the area of ​​the through holes in the grinding surface is preferably 0.003 to 0.5%, more preferably 0.004 to 0.4%, and even more preferably 0.003 to 0.3%.

[0210] (Composition of the polishing layer)

[0211] Examples of resins constituting the abrasive layer include: polyurethane-based resins such as polyurethane and polyurethane-polyurea; acrylic-based resins such as polyacrylate and polyacrylonitrile; ethylene-based resins such as polyvinyl chloride, polyvinyl acetate, and polyvinylidene fluoride; polysulfone-based resins such as polysulfone and polyethersulfone; acylated cellulose-based resins such as acetylated cellulose and butyrylated cellulose; polyamide-based resins; and polystyrene-based resins. Among these, polyurethane resins are more preferred when considering compression properties and flexibility.

[0212] The abrasive layer can be composed of one type of resin or two or more types of resin.

[0213] Furthermore, the abrasive layer preferably has continuous air bubbles. Continuous air bubbles, as referred to here, mean foaming with spaces formed by adjacent air bubbles connected to each other through interconnecting pores. Specifically, it can be a resin obtained by a wet film-forming method or a foam obtained by dry molding or injection molding. Abrasive layers obtained by a wet film-forming method are preferred, as they are expected to exhibit good flexural and tensile properties.

[0214] In this specification, "resin obtained by wet film-forming method" refers to a resin (preferably a polyurethane resin) that forms a film using the wet film-forming method. The wet film-forming method involves dissolving the resin to be formed in an organic solvent, coating the resin solution onto a sheet-like substrate, and then passing it through a coagulation solution to solidify the resin. Resins obtained by wet film-forming typically have multiple teardrop-shaped bubbles (anisotropic, with a shape whose diameter increases from the abrasive surface of the abrasive pad towards the bottom). Therefore, resins obtained by wet film-forming can also be referred to as resins having multiple teardrop-shaped bubbles. The multiple teardrop-shaped bubbles are preferably in the form of continuous bubbles.

[0215] (groove)

[0216] In the first embodiment of the present invention, the polishing pad preferably has grooves on the polishing surface of the polishing layer. The grooves do not penetrate the polishing layer and can be distinguished from through holes.

[0217] Examples of grooves include embossed grooves obtained by embossing the grinding surface and cutting grooves obtained by cutting with a cutting tool. Among these, embossed grooves are preferred. By providing grooves such as embossed grooves, burrs are less likely to form on the grinding surface, and a grinding pad suitable for fine grinding can be obtained.

[0218] The depth of the groove is not particularly limited as long as it is less than the thickness of the abrasive layer, but is preferably 50-90% of the thickness of the abrasive layer, more preferably 60-80%. If the groove disappears due to the grinding of the workpiece, the flowability of the abrasive slurry will be lost, the abrasive performance will decrease, and the abrasive pad will reach the end of its lifespan. Therefore, a deeper groove depth is preferred. On the other hand, to increase the groove depth, it is necessary to increase the processing pressure or processing temperature, which may cause deformation of the substrate (PET) on the back of the abrasive layer or deterioration of the surface of the abrasive layer. If the groove depth is within the above range, these problems are less likely to occur.

[0219] The cross-sectional shape of the grooves is not particularly limited; they can be arc-shaped, U-shaped, V-shaped, rectangular, trapezoidal, or other polygonal shapes, or combinations of two or more of these shapes. Furthermore, there are no particular restrictions on the number or shape of the grooves; they can be adjusted appropriately according to the intended use of the abrasive pad. Examples of shapes include grid-like, radial, concentric, and honeycomb patterns, and combinations thereof are also possible.

[0220] In addition, the abrasive pad of the first aspect of the present invention can be opened on the surface of the abrasive layer by grinding (grinding wheel treatment), or it can be cut.

[0221] In the polishing pad of the first embodiment of the present invention, when the polishing surface is set as the upper surface and its opposite surface is set as the lower surface, the uppermost part 4' of the light-transmitting member may be located at a position higher than the lowermost part 8' of the groove, at the same position as the lowermost part 8', or at a position lower than the lowermost part 8'. Preferably, it is located at the same position as the lowermost part 8' of the groove or at a position lower than the lowermost part 8' of the groove. More preferably, the uppermost part 4' of the light-transmitting member is located at a position lower than the lowermost part 8' of the groove. Generally, the lifespan of the polishing pad ends when the groove on the polishing surface disappears. However, if the uppermost part of the light-transmitting member is located at the same position as the lowermost part of the groove or at a position lower than the lowermost part of the groove, the polishing pad can be used until the groove disappears.

[0222] Furthermore, in conventional polishing pads, if the uppermost part 4' of the light-transmitting component is positioned at the same level as or lower than the lowermost part 8' of the groove, the slurry and polishing debris are not easily discharged from the groove, potentially leading to a decrease in light transmittance over time. In contrast, a polishing pad according to an embodiment of the present invention (…) Figure 4A In the grinding pad, the slurry and grinding debris that enter the recess of the first through hole are moved to the side of the first through hole due to the centrifugal force during the grinding process. They are not easily seen from the second through hole, which has a smaller equivalent circle diameter, thus preventing a decrease in light transmittance. Furthermore, even after most of the slurry has moved to the side of the recess, only a small amount of slurry remains on the surface of the light-transmitting component, making it less likely for the slurry to cause a decrease in light transmittance, thus enabling stable light detection.

[0223] (advantage)

[0224] In the polishing pad of the first embodiment of the present invention, the water contact angle of the surface of the polishing side of the light-transmitting member is less than 80 degrees, so that the presence or absence of slurry on the surface of the polishing side of the light-transmitting member has almost no effect on the light transmittance. Therefore, the polishing endpoint can be determined with high precision.

[0225] Furthermore, in the polishing pad of the first embodiment of the present invention, when the polishing surface is set as the upper surface and its opposite surface as the lower surface, its effect is achieved regardless of whether the light-transmitting member is at the same height as the polishing surface or at a lower position than the polishing surface. In particular, its effect is better when the light-transmitting member is at a lower position than the polishing surface. That is, when the light-transmitting member is at a lower position than the polishing surface, there is a recess (e.g., a cylindrical recess) formed by the surface of the light-transmitting member and the side of the through hole, into which the slurry enters. Most of the slurry entering the recess is moved to the side by centrifugal force and discharged through the embossing groove. Therefore, over time, there may be times when slurry is present in the area through which the laser passes on the surface of the light-transmitting member (times when a large amount of slurry flows into the recess, times when it is not completely discharged, etc.) and times when slurry is not present. When the surface of a light-transmitting component has high water repellency, the slurry adheres to the window surface in a droplet or stripe-like pattern due to lack of affinity. Therefore, compared to the parallel light transmittance in the area where the laser passes through without the slurry, the parallel light transmittance with the slurry is significantly reduced due to light scattering caused by the droplet-like slurry, easily leading to uneven light transmittance during grinding. The grinding pad of the first embodiment of the present invention reduces the water contact angle (hydrophilization) of the surface of the light-transmitting component on the grinding side, thereby preventing the slurry from forming droplets and allowing it to wet and diffuse on the window surface. This suppresses light scattering and reduces the variation in light transmittance between the presence and absence of slurry, thus suppressing uneven light transmittance during grinding.

[0226] The abrasive pad of the first aspect of the present invention can be manufactured, for example, by the method described in the item "Method for manufacturing an abrasive pad of the first aspect".

[0227] <<Second Method of Grinding Pad>>

[0228] In the second aspect of the present invention, the abrasive layer has an abrasive surface for abrading the workpiece, the abrasive pad has a through hole extending from the abrasive surface to its opposite side, the light-transmitting member is arranged such that when viewed from the abrasive surface side of the abrasive pad along the thickness direction of the abrasive pad, the light-transmitting member exists within the through hole, and the surface of the light-transmitting member on the abrasive surface side is coated with a hydrophilic resin.

[0229] Within the scope of this specification and claims, a polishing layer refers to a layer having a surface (polishing surface) that contacts and polishes a workpiece such as a semiconductor device during polishing. The workpiece is not particularly limited; examples include product substrates containing multiple memory or processor dies, test substrates, bare substrates, and gate substrates. The substrate can be at various stages of integrated circuit manufacturing; for example, the substrate can be a bare wafer, or it can be one or more stacked layers and / or patterning layers.

[0230] In this specification, the surface of the polished side of the light-transmitting component coated with hydrophilic resin refers to the coated surface of the polished side of the light-transmitting component.

[0231] In addition, in this specification, the surface of the polished side of the light-transmitting component coated with hydrophilic resin is sometimes abbreviated as "the surface of the light-transmitting component" or "the polished side of the light-transmitting component", etc.

[0232] In addition, in this specification, the uppermost part of the light-transmitting member coated with hydrophilic resin refers to the upper surface of the coating portion 9 on the surface of the light-transmitting member 4 located on the side of the polished surface when the polished surface is set as the upper surface and the opposite surface is set as the lower surface.

[0233] <Translucent Components>

[0234] The second aspect of the present invention provides a polishing pad with a light-transmitting member, i.e., a window member. Light is irradiated onto the workpiece through the light-transmitting member, thereby enabling the detection of the moment when the workpiece reaches the desired surface characteristics and planar state. Optical endpoint detection uses visible light (white light), such as lasers or lamps.

[0235] The light-transmitting member is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member exists within the through hole. Here, "arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member exists within the through hole" means that the light-transmitting member can be identified when viewed from the grinding surface of the grinding pad along the thickness direction. This concept includes the following cases: (1) such as Figure 2B , Figure 3B As shown, the light-transmitting component is connected (or bonded) to the side (sidewall) of the through hole provided in the polishing layer; (2) as Figure 4B or Figure 4C As shown, another layer with through holes is provided below the polishing layer. The through holes have an equivalent circle diameter smaller than that of the through holes in the polishing layer. A light-transmitting member is disposed on the exposed portion 7 caused by the size difference between the through holes in the polishing layer and the through holes in the other layer; (3) as Figure 5B As shown, the light-transmitting component is sandwiched between the polished layer and other layers, arranged such that a portion of the light-transmitting component is exposed within the through-hole; (4) as Figure 6B As shown, through holes are provided in both the polishing layer and the other layer, and the light-transmitting member is arranged in such a way that it is in contact (or bonded) with the side of the through hole of either or both of them. Preferably, it is (1), (2) or (4), more preferably (1) or (2), and even more preferably (2).

[0236] As a light-transmitting component, a transparent resin component is preferred. There are no particular limitations on the transparent resin component as long as it has a degree of transparency that allows light to pass through. For example, thermosetting resins such as polyurethane resin, polyester resin, phenolic resin, urea resin, melamine resin, epoxy resin, and acrylic resin can be used; thermoplastic resins such as polyurethane resin, polyester resin, polyamide resin, cellulose resin, acrylic resin, polycarbonate resin, halogen resin (polyvinyl chloride, polytetrafluoroethylene, polyvinylidene fluoride, etc.), polystyrene resin, and olefin resin (polyethylene, polypropylene, etc.); rubbers such as butadiene rubber and isoprene rubber; photocurable resins that are cured by ultraviolet light, electron beams, or other light; and photosensitive resins, etc. Among these, acrylic resins, polyurethane resins, polyester resins, and polystyrene resins are preferred, and acrylic resins are more preferred.

[0237] <Coating with hydrophilic resin>

[0238] The surface of the light-transmitting component preferably has a hydrophilic resin coating on the grinding side. Not only the grinding side, but also the opposite side (back side) and side surfaces can be coated with hydrophilic resin. However, coating the back and side surfaces also increases costs. Furthermore, hydrophilization of the back and side surfaces is irrelevant to the effectiveness of this invention; therefore, it is preferable that only the grinding side surface is coated with hydrophilic resin. By coating the grinding side surface with hydrophilic resin, uneven light transmittance caused by the presence of slurry on the surface of the light-transmitting component can be suppressed. This allows for more precise determination of the grinding endpoint.

[0239] The hydrophilic resin is preferably a resin that exhibits a water contact angle of 80 degrees or less when coated on a flat surface, and more preferably a resin that exhibits a water contact angle of 50 degrees or less.

[0240] As a hydrophilic resin, a resin having ion-binding hydrophilic groups is preferred. A resin having ion-binding hydrophilic groups is a resin containing ion-binding hydrophilic groups composed of cations and anions. The cations and anions are preferably organic cations or organic anions, more preferably composed of organic cations and organic anions. Furthermore, it is preferable that one of the cations or anions is covalently bonded to the atoms constituting the resin. By covalently bonding with the atoms constituting the resin, the leaching of ion-binding hydrophilic groups from the resin containing ion-binding hydrophilic groups can be suppressed, preventing contamination of the polishing slurry.

[0241] Resins with ion-binding hydrophilic groups are preferably of the inclusion type: A + B - (A + B is a cation. - A resin containing an ion-binding hydrophilic group (represented by an anion), more preferably a resin containing -A + B - or -B - A + The resin represented by the ion-binding hydrophilic group. The ion-binding hydrophilic group can be imparted to the resin, for example, by polymerizing a monomer or oligomer containing the ion-binding hydrophilic group with other monomers, oligomers, etc. as needed, or by covalently bonding the side chains of the coating polymer to the ion-binding hydrophilic group.

[0242] Among them, the resin containing ion-binding hydrophilic groups preferably constitutes part or all of the constituent units (monomers) of the resin and has ion-binding hydrophilic groups.

[0243] When the monomer constituting the resin has an ionicly bound hydrophilic group, (before UV irradiation) this monomer preferably contains functional groups with unsaturated double bonds in its side chains, and more preferably contains functional groups with vinyl unsaturated bonds (e.g., vinyl, allyl, acrylic, methacrylic, acryloyl, methacryl, etc.). Because the monomer constituting the resin has unsaturated double bonds in its side chains, the resin can be cured by UV irradiation.

[0244] Monomers containing ion-binding hydrophilic groups can be synthesized or commercially available products can be used. Examples of commercially available monomers containing ion-binding hydrophilic groups include amino ions (manufactured by Nippon Emulsifier Co., Ltd.).

[0245] In resins containing ion-binding hydrophilic groups, the cationic portion of the ion-binding hydrophilic group may be covalently bonded to the monomer constituting the resin (preferably a side chain of the monomer) and ionically bonded to the anionic portion of the ion-binding hydrophilic group (preferably having a -A terminal on the side chain). + B -The structure can be either covalently bonded to the anionic portion of the ion-binding hydrophilic group and the monomer constituting the resin (preferably the side chain of the monomer), or ionically bonded to the cationic portion of the ion-binding hydrophilic group (preferably having a -B at the end of the side chain). - A + (Structure of the resin). Preferably, in the resin containing ion-binding hydrophilic groups, the cationic portion of the ion-binding hydrophilic group is covalently bonded to the monomer constituting the resin and ionically bonded to the anionic portion of the ion-binding hydrophilic group.

[0246] As a resin containing ion-binding hydrophilic groups, a resin having ion-binding hydrophilic groups in its side chains is preferred.

[0247] There are no particular limitations on the types of ion-binding hydrophilic groups; for example, groups containing ammonium cations, etc., can be included. Cation, Sulfonium cation, Imidazole Cations, Pyridine Hydrophilic groups of cations, etc. Preferably, the hydrophilic group contains an ammonium cation, more preferably -A. + B - (A + It is an ammonium cation, B - (for anions), more preferably -NR3 + B - (R represents substituents such as hydrogen atoms and alkyl groups).

[0248] As -A + B - The ion-binding hydrophilic group, preferably -NR3 + X - The hydrophilic group represented (in the formula, R independently represents a hydrogen atom or a substituted or unsubstituted alkyl group, X...) - (Indicates anion).

[0249] Additionally, X - There are no particular limitations, but it is preferred to include sulfate anions and sulfonate anions with alkyl groups (e.g., alkyl sulfate ions, polyoxyalkylene alkyl ether sulfate ions, polyoxyalkylene alkylphenyl ether sulfate ions, alkyl sulfonate ions, alkylbenzene sulfonate ions, etc.). These ionic structures are presumably less likely to dissolve from the resin because they are hydrophilic while having hydrophobic terminal groups.

[0250] Examples of monomers having ion-binding hydrophilic groups include, for example, the monomers (constituents) shown in Japanese Patent No. 6209639.

[0251]

[0252] (where R is in the formula) b1R is a hydrogen atom or a methyl group. b2 It is a hydrogen atom or a substituted or unsubstituted C atom 1-6 Alkyl group, nb is an integer from 1 to 6, Y b - is the anion represented by the following formula (2').

[0253] R'-O-(A'O) m -SO3 -

[0254] (In the formula, R' represents C with or without substitution) 12-14 A straight-chain alkyl group, where A' is C 2-4 (A straight-chain or branched alkylene groups, where m is the average molar number of A'O additions, ranging from 2 to 50.)

[0255] Specific examples include salts of (meth)acrylic monomers and polyoxyalkylene alkyl ether sulfates, such as dimethylaminoethyl (meth)acrylate and diethylaminoethyl (meth)acrylate.

[0256] As a hydrophilic resin, a resin containing ion-binding hydrophilic groups is preferred, more preferably a resin having hydrophilic groups containing ammonium cations, and even more preferably a resin containing hydrophilic groups (-NR3) composed of ammonium cations and anions. + The resin of X-) is more preferably an acrylic resin containing a hydrophilic group composed of ammonium cations and anions. Additionally, a photocurable resin containing a hydrophilic group composed of ammonium cations and anions is also preferred, and a photocurable acrylic resin containing a hydrophilic group composed of ammonium cations and anions is even more preferred.

[0257] Examples of resins containing ion-binding hydrophilic groups include ACRIT 8WX (modified acrylate polymer, manufactured by Taisei Fine Chemical Co., Ltd.), a photocurable polymer containing ammonium cations.

[0258] There are no particular limitations on the coating method using hydrophilic resins. For example, coating with hydrophilic resins can be carried out as follows: a hydrophilic photocurable resin, preferably a photocurable resin containing ion-binding hydrophilic groups, is mixed with a photopolymerization initiator, coated onto the surface of a translucent component, and then cured by irradiation with ultraviolet light or the like. In this case, in addition to hydrophilic photocurable resins, photocurable resins used as adhesives can also be mixed in.

[0259] Alternatively, the coating can be obtained by polymerizing a monomer containing an ion-binding hydrophilic group together with other monomers (preferably acrylic monomers) using conventional methods (solution polymerization, photopolymerization). In the case of solution polymerization, the polymerized solution is coated onto the surface of the endpoint detection window and dried to obtain a coating. In the case of photopolymerization, the monomer solution is coated onto the surface of the endpoint detection window and subjected to ultraviolet irradiation to obtain a coating.

[0260] There are no particular limitations on the type of light-curing resin used as an adhesive, and conventionally known light-curing resins can be used. For example, examples include polyfunctional (meth)acrylate compounds having two or more (meth)acryloyl groups per molecule, such as NK ESTER (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), ARONIX (manufactured by Toa Gosei Co., Ltd.), KAYARAD (manufactured by Nippon Kayaku Co., Ltd.), and FANCRYL (manufactured by Hitachi Chemical Co., Ltd.). Preferably, the light-curing resin has a degree of transparency that allows light to pass through after curing.

[0261] As a photopolymerization initiator, there are no particular restrictions as long as it can cure photocurable resins through irradiation with ultraviolet light, electron beams, etc., and well-known photopolymerization initiators can be used. For example, free radical polymerization initiators, cationic polymerization initiators, and anionic polymerization initiators can be mentioned. As a commercially available product, IRGACURE (manufactured by IGM Resin BV) can be mentioned.

[0262] <Configuration of Transparent Components>

[0263] In the second aspect of the abrasive pad of the present invention, when the abrasive surface is set as the upper surface and its opposite surface is set as the lower surface, the uppermost part of the light-transmitting member coated with hydrophilic resin can be at the same height as the abrasive surface, or it can be lower than the abrasive surface, preferably lower than the abrasive surface. Figure 2BBy ensuring that the top of the translucent component coated with hydrophilic resin is lower than the grinding surface, it is possible to prevent grinding scratches caused by the harder translucent component than the grinding layer. Furthermore, if the top of the translucent component is lower than the grinding surface, the slurry enters the recess formed by the translucent component and the side of the through-hole. Most of it will move to the side of the through-hole due to centrifugal force and be discharged through the groove. Therefore, it is easy for a small amount of slurry to remain on the surface of the translucent component, or for no slurry to remain. However, when using conventional grinding pads, the light transmittance differs between cases where a small amount of slurry remains on the surface of the translucent component and cases where no slurry remains, making it difficult to accurately determine the grinding endpoint. In contrast, the grinding pad of the second aspect of the present invention has better affinity with the slurry by coating the surface of the grinding surface of the light-transmitting member with the above-mentioned resin. Even in the case of a small amount of slurry, it will spread evenly on the window surface, thereby reducing the variation in light transmittance from the beginning to the end of the grinding process. Even if the uppermost part of the light-transmitting member is in a position lower than the grinding surface, especially if the uppermost part 4' of the light-transmitting member is in the same position as or lower than the lowermost part 8' of the groove, the grinding endpoint can be determined with high accuracy.

[0264] (Water contact angle)

[0265] In the second aspect of the abrasive pad of the present invention, the water contact angle of the surface of the abrasive side of the light-transmitting member coated with hydrophilic resin is preferably 50 degrees or less, more preferably 30 degrees or less, more preferably 20 degrees or less, and even more preferably 5 to 20 degrees. If the water contact angle is within the above range, it is easy to suppress the unevenness of light transmittance caused by the presence of slurry on the surface of the light-transmitting member.

[0266] There are no particular limitations on the water contact angle of the back and sides of the light-transmitting component; the water contact angle can be greater than 50 degrees or greater than 80 degrees. That is, the back and sides of the light-transmitting component may not be coated. Conventional polishing pads typically use window components with a water contact angle greater than 80 degrees. When using windows with hydrophilicity (below 80 degrees), the slurry may cause the window to expand, deform, peel off from the polishing area, or leak. Therefore, the window component preferably has a hydrophobicity with a water contact angle greater than 80 degrees. In this invention, it is preferable to coat only the polishing surface with a hydrophilic resin so that the water contact angle is less than 50 degrees.

[0267] (Pass rate)

[0268] In the second aspect of the polishing pad of the present invention, the difference between the visible light transmittance (hereinafter referred to as light transmittance) when water is not adhering to the surface of the light-transmitting member coated with hydrophilic resin and the visible light transmittance when water is adhering to the surface of the light-transmitting member is preferably within 10%, more preferably within 8%, even more preferably within 6%, and even more preferably within 5%. By keeping the difference in light transmittance within the above range, it is less likely to occur a difference in light transmittance between the presence and absence of slurry on the surface of the resin-coated light-transmitting member, enabling high-precision determination of the polishing endpoint.

[0269] In the abrasive pad of the second aspect of the present invention, the light transmittance when water is attached to the surface of the light-transmitting member coated with hydrophilic resin is preferably 60% or more, more preferably 62% or more, even more preferably 65% ​​or more, even more preferably 70% or more, even more preferably 75% or more, and even more preferably 80% or more.

[0270] In the abrasive pad of the second aspect of the present invention, the light transmittance when water is not allowed to adhere to the surface of the light-transmitting member coated with hydrophilic resin is preferably 60% or more, more preferably 62% or more, even more preferably 65% ​​or more, even more preferably 70% or more, even more preferably 75% or more, even more preferably 80% or more, even more preferably 85% or more.

[0271] Light transmittance can be measured using a spectrophotometer to measure the transmission spectrum from 300 to 1000 nm, and the result is obtained as the visible light transmittance (%) according to the Japanese Industrial Standard (JIS A5759:2008). Specifically, the transmittance is calculated as follows: the transmittance for each wavelength in the range of 380 to 780 nm is measured, and the transmittance at each wavelength is multiplied by a weighted average obtained from the CIE (International Commission on Illumination) daylight D65 spectral distribution, the CIE light adaptation standard relative visual sensitivity wavelength distribution, and the wavelength intervals.

[0272] In addition, regarding the determination of light transmittance when water is applied to the surface of a translucent component coated with a hydrophilic resin, a sufficient amount of water (e.g., about 0.01 to 0.03 mL for a translucent component cut into 9 mm × 50 mm sizes) can be sprayed onto the entire surface of the ground side of the translucent component. The translucent component is then placed perpendicular to the ground for 60 seconds to remove the water, and the resulting translucent component is used for measurement.

[0273] (Through hole)

[0274] A through-hole is a hole that extends from the polishing surface to the opposite side of the polishing pad when viewed from the polishing surface side along the thickness direction of the polishing pad. The through-hole preferably penetrates the polishing layer in a manner parallel to the thickness direction or perpendicular to the polishing surface.

[0275] One through hole can be set in the polishing layer, or two or more through holes can be set separately and independently.

[0276] Examples of through-hole shapes, as seen when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, or the shapes of through-holes in the grinding surface, include: circles, ellipses, triangles, quadrilaterals, hexagons, octagons, etc. Alternatively, a shape formed by the partial overlap of multiple of the above shapes, either identical or different. Among these, a circle is particularly preferred as it does not form corners where grinding debris tends to accumulate.

[0277] (Equivalent circle diameter)

[0278] Within the scope of this specification and claims, the so-called equivalent circle diameter refers to the diameter of a perfect circle whose area is equivalent to that of the figure being measured.

[0279] The equivalent circle diameter of a through hole is the equivalent circle diameter of the through hole when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad. It is equivalent to the diameter when the shape of the through hole is circular when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad.

[0280] There is no particular limitation on the equivalent circle diameter of the through hole, but it is preferably 5 to 40 mm, more preferably 5 to 30 mm, and even more preferably 10 to 28 mm.

[0281] Furthermore, relative to the total area of ​​the grinding surface, the area of ​​the through holes in the grinding surface is preferably 0.003 to 0.5%, more preferably 0.004 to 0.4%, and even more preferably 0.005 to 0.3%.

[0282] (Composition of the polishing layer)

[0283] Examples of resins constituting the abrasive layer include: polyurethane-based resins such as polyurethane and polyurethane-polyurea; acrylic-based resins such as polyacrylate and polyacrylonitrile; ethylene-based resins such as polyvinyl chloride, polyvinyl acetate, and polyvinylidene fluoride; polysulfone-based resins such as polysulfone and polyethersulfone; acylated cellulose-based resins such as acetylated cellulose and butyrylated cellulose; polyamide-based resins; and polystyrene-based resins. Among these, polyurethane resins are more preferred when considering compression properties and flexibility.

[0284] The abrasive layer can be composed of one type of resin or two or more types of resin.

[0285] Furthermore, the abrasive layer preferably has continuous air bubbles. Continuous air bubbles, as referred to here, mean foaming with spaces formed by adjacent air bubbles connected to each other through interconnecting pores. Specifically, it can be a resin obtained by a wet film-forming method or a foam obtained by dry molding or injection molding. Abrasive layers obtained by a wet film-forming method are preferred, as they are expected to exhibit good flexural and tensile properties.

[0286] In this specification, "resin obtained by wet film-forming method" refers to a resin (preferably a polyurethane resin) that forms a film using the wet film-forming method. The wet film-forming method involves dissolving the resin to be formed in an organic solvent, coating the resin solution onto a sheet-like substrate, and then passing it through a coagulation solution to solidify the resin. Resins obtained by wet film-forming typically have multiple teardrop-shaped bubbles (anisotropic, with a shape whose diameter increases from the abrasive surface of the abrasive pad towards the bottom). Therefore, resins obtained by wet film-forming can also be referred to as resins having multiple teardrop-shaped bubbles. The multiple teardrop-shaped bubbles are preferably in the form of continuous bubbles.

[0287] The abrasive layer of the abrasive pad constituting the second aspect of the present invention is preferably a resin sheet (preferably a polyurethane sheet) formed by a wet film-forming method, more preferably a polyurethane sheet containing a plurality of teardrop-shaped bubbles, and even more preferably a polyurethane sheet containing a plurality of teardrop-shaped bubbles and having a continuous bubble formed by connecting part or all of the bubbles through a connecting hole.

[0288] (groove)

[0289] In the second embodiment of the present invention, the polishing pad preferably has grooves on the polishing surface of the polishing layer. The grooves do not penetrate the polishing layer and can be distinguished from through holes.

[0290] Examples of grooves include embossed grooves obtained by embossing the grinding surface and cutting grooves obtained by cutting with a cutting tool. Among these, embossed grooves are preferred. By providing grooves such as embossed grooves, burrs are less likely to form on the grinding surface, and a grinding pad suitable for fine grinding can be obtained.

[0291] The depth of the groove is not particularly limited as long as it is less than the thickness of the abrasive layer, but is preferably 50-90% of the thickness of the abrasive layer, more preferably 60-80%. If the groove disappears due to the grinding of the workpiece, the flowability of the abrasive slurry will be lost, the abrasive performance will decrease, and the abrasive pad will reach the end of its lifespan. Therefore, a deeper groove depth is preferred. On the other hand, to increase the groove depth, it is necessary to increase the processing pressure or processing temperature, which may cause deformation of the substrate (PET) on the back of the abrasive layer or deterioration of the surface of the abrasive layer. If the groove depth is within the above range, these problems are less likely to occur.

[0292] The cross-sectional shape of the grooves is not particularly limited; they can be arc-shaped, U-shaped, V-shaped, rectangular, trapezoidal, or other polygonal shapes, or combinations of two or more of these shapes. Furthermore, there are no particular restrictions on the number or shape of the grooves; they can be adjusted appropriately according to the intended use of the abrasive pad. Examples of shapes include grid-like, radial, concentric, and honeycomb patterns, and combinations thereof are also possible.

[0293] In addition, the abrasive pad of the second aspect of the present invention can be opened on the surface of the abrasive layer by grinding (grinding wheel treatment), or it can be cut.

[0294] In the second aspect of the polishing pad of the present invention, when the polishing surface is set as the upper surface and its opposite surface is set as the lower surface, the uppermost part 4' (i.e., the upper surface of the coating part 9) of the light-transmitting member coated with hydrophilic resin can be positioned higher than the lowermost part 8' of the groove, or at the same position as the lowermost part 8', or at a lower position than the lowermost part 8'. Preferably, it is positioned at the same position as the lowermost part 8' of the groove or lower than the lowermost part 8' of the groove, and more preferably, the uppermost part 4' of the light-transmitting member is positioned lower than the lowermost part 8' of the groove. Generally, the lifespan of the polishing pad ends when the groove on the polishing surface disappears. However, if the uppermost part of the light-transmitting member is positioned at the same position as the lowermost part of the groove or lower than the lowermost part of the groove, the polishing pad can be used until the groove disappears.

[0295] Furthermore, in conventional polishing pads, if the uppermost part 4' of the light-transmitting component is positioned at the same level as or lower than the lowermost part 8' of the groove, the slurry and polishing debris are not easily discharged from the groove, potentially leading to a decrease in light transmittance over time. In contrast, a polishing pad according to an embodiment of the present invention (…) Figure 4B or Figure 4C In the grinding pad, the slurry and grinding debris that enter the recess of the first through hole are moved to the side of the first through hole due to the centrifugal force during the grinding process. They are not easily seen from the second through hole, which has a smaller equivalent circle diameter, thus preventing a decrease in light transmittance. Furthermore, even after most of the slurry has moved to the side of the recess, only a small amount of slurry remains on the surface of the light-transmitting component, making it less likely for the slurry to cause a decrease in light transmittance, thus enabling stable light detection.

[0296] (advantage)

[0297] The second aspect of the present invention provides a polishing pad that coats the surface of the light-transmitting member with a hydrophilic resin, preferably a resin containing ion-binding hydrophilic groups. The light transmittance remains almost unchanged regardless of the presence or absence of the slurry on the surface of the light-transmitting member. This allows for highly accurate determination of the polishing endpoint.

[0298] Furthermore, in the second aspect of the polishing pad of the present invention, when the polishing surface is set as the upper surface and its opposite surface as the lower surface, its effect is achieved regardless of whether the surface of the resin-coated light-transmitting member on the polishing surface side is at the same height as the polishing surface or at a lower position than the polishing surface. In particular, its effect is better when the surface of the light-transmitting member on the polishing surface side is at a lower position than the polishing surface. That is, when the surface of the light-transmitting member on the polishing surface side is at a lower position than the polishing surface, there is a recess (e.g., a cylindrical recess) formed by the surface of the resin-coated light-transmitting member and the side of the through hole, into which the slurry enters. Most of the slurry entering the recess is moved to the side by centrifugal force and discharged through the embossing groove. Therefore, over time, there may be times when slurry is present in the area through which the laser passes on the surface of the light-transmitting member (times when a large amount of slurry flows into the recess, times when it is not completely discharged, etc.) and times when slurry is not present. When the surface of a light-transmitting component has high water repellency, the slurry adheres to the window surface in a droplet or stripe-like pattern due to lack of affinity. Therefore, compared to the parallel light transmittance in the area through which the laser passes without the slurry, the parallel light transmittance with the slurry is significantly reduced due to light scattering caused by the droplet-like slurry, easily leading to uneven light transmittance during the polishing process. The polishing pad of the second aspect of the present invention utilizes a hydrophilic resin, preferably a resin containing ion-binding hydrophilic groups, to coat the polishing surface of the light-transmitting component. This prevents the slurry from forming droplets and allows it to wet and diffuse on the window surface, thus suppressing light scattering and reducing the variation in light transmittance between the presence and absence of the slurry. This, in turn, suppresses uneven light transmittance during the polishing process.

[0299] The abrasive pad of the second aspect of the present invention can be manufactured, for example, by the method described in the item "Method for manufacturing an abrasive pad of the second aspect".

[0300] <<Third-Party Abrasive Pads>>

[0301] The third-party abrasive pad of the present invention is an abrasive pad having a light-transmitting resin component and an abrasive layer, wherein the abrasive layer has an abrasive surface for abrading the workpiece, the abrasive pad has a through hole extending from the abrasive surface to its opposite side, the light-transmitting resin component is arranged such that when viewed from the abrasive surface side of the abrasive pad along the thickness direction of the abrasive pad, the light-transmitting resin component is present in the through hole, and the surface of the light-transmitting resin component on its abrasive surface side is grafted with a hydrophilic monomer.

[0302] Alternatively, the third-party abrasive pad of the present invention may also be referred to as an abrasive pad having a light-transmitting resin member and an abrasive layer, wherein the abrasive layer has an abrasive surface for abrading the workpiece, the abrasive pad has a through hole extending from the abrasive surface to its opposite side, the light-transmitting resin member is arranged such that when viewed from the abrasive surface side of the abrasive pad along the thickness direction of the abrasive pad, the light-transmitting resin member exists within the through hole, and the resin on the abrasive surface side of the light-transmitting resin member has a polymer comprising hydrophilic monomers as constituent units in its side chains.

[0303] Within the scope of this specification and claims, a polishing layer refers to a layer having a surface (polishing surface) that contacts and polishes a workpiece such as a semiconductor device during polishing. The workpiece is not particularly limited; examples include product substrates containing multiple memory or processor dies, test substrates, bare substrates, and gate substrates. The substrate can be at various stages of integrated circuit manufacturing; for example, the substrate can be a bare wafer, or it can be one or more stacked layers and / or patterning layers.

[0304] <Translucent Resin Components>

[0305] The third-party polishing pad of the present invention has a light-transmitting resin component, i.e., a window component. By irradiating the workpiece with light through the light-transmitting resin component, it is possible to detect the moment when the workpiece reaches the desired surface characteristics and planarity. Optical endpoint detection uses visible light (white light), such as lasers or lamps.

[0306] The light-transmitting resin component is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component exists within the through-hole. Here, "arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component exists within the through-hole" means that the light-transmitting resin component can be identified when viewed from the grinding surface of the grinding pad along the thickness direction. This concept includes the following cases: (1) such as Figure 2B , Figure 3B As shown, the light-transmitting resin component is connected (or bonded) to the side (sidewall) of the through hole provided in the polishing layer; (2) as Figure 4B or Figure 4C As shown, a layer with through holes is provided below the polishing layer. The through holes have an equivalent circle diameter smaller than that of the through holes in the polishing layer. A light-transmitting resin component is disposed on the exposed portion 7, which is caused by the size difference between the through holes in the polishing layer and the through holes in the other layers; (3) as shown Figure 5B As shown, a light-transmitting resin component is sandwiched between the polished layer and other layers, arranged such that a portion of the light-transmitting resin component is exposed within the through-hole; (4) as Figure 6B As shown, through holes are provided in both the polishing layer and the other layer, and a light-transmitting resin component is disposed in such a way that it is in contact (or bonded) with the side of the through hole of any one or both of them. Preferably, it is (1), (2) or (4), more preferably (1) or (2), and even more preferably (2).

[0307] As a light-transmitting resin component, there are no particular limitations on the type of resin that allows light to pass through. For example, thermosetting resins such as polyurethane resin, polyester resin, phenolic resin, urea resin, melamine resin, epoxy resin, and acrylic resin can be used; thermoplastic resins such as polyurethane resin, polyester resin, polyamide resin, cellulose resin, acrylic resin, polycarbonate resin, halogen resin (polyvinyl chloride, polytetrafluoroethylene, polyvinylidene fluoride, etc.), polystyrene resin, and olefin resin (polyethylene, polypropylene, etc.); rubbers such as butadiene rubber and isoprene rubber; photocurable resins that are cured by ultraviolet light, electron beams, or other light; and photosensitive resins. Among these, acrylic resin, polyurethane resin, polyester resin, and polystyrene resin are preferred, and acrylic resin is more preferred.

[0308] The transparent resin component preferably has a transparency of 60% or more when irradiated with light of wavelengths from 380 nm to 780 nm (sometimes simply referred to as light transmittance in this specification), more preferably 65% ​​or more, even more preferably 70% or more, even more preferably 75% or more, and even more preferably 80% or more. The visible light transmittance can be measured by measuring the transmission spectrum of wavelengths from 300 to 1000 nm using a spectrophotometer, and determined as the visible light transmittance (%) according to Japanese Industrial Standard (JIS A5759:2008).

[0309] (Grafting)

[0310] The third-party abrasive pad of the present invention has hydrophilic monomers grafted onto the surface of the abrasive side of the translucent resin component.

[0311] Within the scope of this specification and claims, "grafting a hydrophilic monomer onto the surface of the polished side of a translucent resin component" means that the hydrophilic monomer is bound to the translucent resin on the surface of the polished side through graft polymerization. Therefore, the resin present on the surface of the polished side of the translucent resin component has a polymer in its side chains comprising hydrophilic monomers as constituent units.

[0312] The third-party abrasive pad of the present invention reduces the adhesion and fixation of abrasive debris to the surface of the translucent resin component by grafting and polymerizing a hydrophilic monomer (hereinafter, sometimes referred to as grafting) onto the surface of the translucent resin component. The reason why grafting reduces the adhesion and fixation of abrasive debris to the surface of the translucent resin component is not yet clear, but it is speculated as follows: That is, by grafting, the resin on the surface of the translucent resin component has longer side chains. It is speculated that these longer side chains adsorb water molecules to form a water film, making it difficult for abrasive debris flowing to the surface of the translucent resin component to adhere and fix to the surface of the translucent resin component. Furthermore, the centrifugal force during the abrasive process causes the abrasive debris to flow out of the surface of the translucent resin component, thereby preventing the adhesion and fixation of abrasive debris to the surface of the translucent resin component.

[0313] As a grafting process, plasma grafting polymerization is preferred. Plasma grafting polymerization is a method that uses free radicals formed through plasma surface treatment as a starting point to react with monomers such as acrylic acid to form a grafted polymer surface (Journal of the Chinese Society of Fibers, 1985, Vol. 41, No. 10, pp. 388-393).

[0314] Plasma treatment refers to the process of irradiating a solid surface with plasma generated by the ionization of an inert gas environment through discharge.

[0315] Examples of inactive gases used in the aforementioned plasma treatment include nitrogen, argon, oxygen, helium, neon, and xenon.

[0316] Plasma can be generated using any known method for plasma generation. For example, a monomer can be placed between parallel plate electrodes connected to a high-frequency generator under vacuum, using either the external or internal parallel plates of the vacuum chamber to generate plasma. Alternatively, an electric field can be created using an external induction coil to generate plasma of ionized gas. Furthermore, electrodes with opposite charges can be spaced apart and directly placed into the vacuum chamber to generate plasma.

[0317] Regarding the grafting of hydrophilic monomers, for example, it is preferable to remove the transparent resin component from the plasma treatment device after plasma treatment of the surface of the polished side of the transparent resin component, and immerse it in an aqueous solution containing hydrophilic monomers, thereby causing the hydrophilic unsaturated monomers to be grafted and polymerized onto the transparent resin component.

[0318] Within the scope of this specification and claims, a hydrophilic monomer is a monomer having functional groups around it that can adsorb water molecules.

[0319] As a hydrophilic monomer, it is preferred to be a hydrophilic monomer having unsaturated double bonds, and more preferably a hydrophilic monomer having vinyl or allyl groups.

[0320] As for the hydrophilic monomers used for grafting, there are no particular restrictions on the type of monomer; conventionally known monomers can be used. Examples of hydrophilic monomers include: acrylamide, methacrylamide, N-vinylpyrrolidone; acrylic acid, methacrylic acid, p-styrene sulfonic acid, vinyl sulfonic acid, 2-methacryloyloxyethyl sulfonic acid, 3-methacryloyloxy-2-hydroxypropyl sulfonic acid, allyl sulfonic acid, methyl allyl sulfonic acid and their ammonium salts, as well as alkali metal salts, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, diethylaminoethyl acrylate and diethylaminoethyl methacrylate, hydrochloric acid, nitric acid, dimethylsulfuric acid, diethylsulfuric acid or quaternary salts of 2-vinylpyridine and 4-vinylpyridine. Preferably, the monomer is an acrylic acid monomer, more preferably acrylic acid, methacrylic acid, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, acrylamide, methacrylamide, 2-acrylamide-2-methylpropanesulfonic acid, N,N-dimethylaminoethyl methacrylate or N,N-dimethylaminoethyl acrylate, even more preferably acrylic acid or methacrylic acid, and even more preferably acrylic acid.

[0321] As a hydrophilic monomer, it can be used alone or in combination with two or more.

[0322] Furthermore, the translucent resin component can also be further reacted with the grafted polymer formed by grafting the surface of the polished side to form a composite. As the polymer forming the composite, if the grafted polymer is a monomer containing an acrylic monomer (e.g., acrylic acid, methacrylic acid), maleic anhydride, or other monomers with carboxylic acid groups (anionic polymers), examples of polymers forming the composite include: polyethylene glycol, polyvinylpyrrolidone, polyxyl viologen, polyethyleneimine, and cationic polymers such as polyvinylpyridine chloride and polyvinylbenzyltrimethylammonium chloride. Conversely, if the grafted polymer is a basic monomer containing acrylamide, methacrylamide, vinylpyridine, N,N-dimethylaminoethyl methacrylate, or N,N-dimethylaminoethyl acrylate, or other polymers forming the composite (cationic polymers), examples of polymers forming the composite include: polyacrylic acid, polymethacrylic acid, poly2-acrylamide-2-methylpropanesulfonic acid, polystyrene sulfonic acid, and polyvinyl sulfonic acid.

[0323] Preferably, the resin grafted onto the surface of the acrylic monomer is a polymer selected from polyethylene glycol, polyvinylpyrrolidone, polyxyl viologen, polyethyleneimine, polyvinylpyridine chloride, and polyvinylbenzyltrimethylammonium chloride, which forms a complex and is bound together by intermolecular interactions. More preferably, it is bound together by polyvinylbenzyltrimethylammonium chloride through intermolecular interactions. Intermolecular interactions, such as hydrogen bonds and ionic bonds, play a role between the polymer chains resulting from the graft polymerization and the polymer forming the complex, forming a complex composed of ionic complexes.

[0324] By forming a complex with the polymer that forms the complex, the adsorption sites for water molecules increase due to the counterions present in the ions of the grafted group and the polymer that forms the complex, thus further reducing the contact angle and improving the hydrophilicity of the surface of the translucent resin component. In addition, since a water film easily forms on the surface, dirt such as grinding debris becomes difficult to adhere to and adhere to.

[0325] Composite formation using polymers that form composites can be achieved, for example, by immersing a translucent resin component, which is formed by grafting and polymerizing a hydrophilic monomer, in an aqueous solution of the polymer that forms the composite for a predetermined time.

[0326] Not only can the resin on the surface of the translucent resin component be grafted onto the grinding surface, but the resin on the opposite side (back side) and the side surfaces can also be grafted. However, grafting the back and side surfaces as well would increase costs. Furthermore, grafting the back and side surfaces is irrelevant to the effectiveness of this invention. Additionally, if the resin on the side and back surfaces of the translucent resin component is grafted, the surface in contact with the grinding layer becomes hydrophilic. This could lead to the translucent resin component swelling and deforming due to the slurry, peeling off from the grinding area, or slurry leakage. For these reasons, it is preferable to graft the resin only onto the surface of the grinding surface.

[0327] (Water contact angle)

[0328] In the third-party polishing pad of the present invention, the water contact angle of the polishing surface of the translucent resin component is 80 degrees or less. Preferably, the water contact angle is 60 degrees or less, more preferably 50 degrees or less, even more preferably 30 degrees or less, even more preferably 20 degrees or less, even more preferably 1 to 20 degrees, even more preferably 2 to 15 degrees, and even more preferably 3 to 10 degrees. If the water contact angle is within the above range, it is easy to prevent polishing debris from adhering to and adhering to the polishing surface of the translucent resin component (window component).

[0329] The reason why the adhesion and fixation of abrasive debris to the abrasive surface of the translucent resin component (window component) can be easily prevented by the water contact angle being within the above-mentioned range is speculated as follows.

[0330] As described above, it is believed that the third-party abrasive pad of the present invention, through grafting, makes the resin on the surface of the abrasive side of the translucent resin component have longer side chains. Water molecules are adsorbed onto the side chains, and adjacent side chains carry the same charge, thus repelling each other. Therefore, a large number of water molecules are adsorbed, and the wettability is improved. At this time, it is believed that by making the water contact angle of the surface of the abrasive side of the translucent resin component less than 80 degrees hydrophilic, the water molecules attached to the side chain portion can easily form a water film, and the abrasive debris can easily be discharged from the translucent resin component together with the slurry. Therefore, the result is that the adhesion and fixation of abrasive debris can be suppressed.

[0331] In the third-party abrasive pad of the present invention, there are no particular limitations on the water contact angles of the back and sides of the translucent resin component. Therefore, the water contact angles of the back and sides can be greater than 80 degrees. That is, the back and sides of the translucent resin component may not need to be grafted.

[0332] In conventional polishing pads, window components typically have a water contact angle greater than 80 degrees. When using windows where the entire surface of the window component has a water contact angle of less than 80 degrees, the slurry may cause the window to swell, deform, peel off from the polishing area, or leak. Therefore, as a window component material, a hydrophobic window component with a water contact angle greater than 80 degrees is preferred, and it is even more preferable to set the water contact angle of only the polished surface side to less than 80 degrees. As in this invention, a light-transmitting resin component is preferably used where only the resin on the polished surface side is grafted, thereby achieving a water contact angle of less than 80 degrees on the polished surface side surface (while the water contact angles on the sides and back are greater than 80 degrees).

[0333] In the third-party abrasive pad of the present invention, when the abrasive surface is set as the upper surface and its opposite surface is set as the lower surface, the grafted surface 9 of the light-transmitting resin member (the upper surface of the light-transmitting resin member) can be the same as the abrasive surface or lower than the abrasive surface, preferably lower than the abrasive surface. Figure 2B By ensuring that the grafted surface 9 of the translucent resin component is lower than the polishing surface, it is possible to prevent the formation of polishing scratches caused by the translucent resin component, which is harder than the polishing layer. Furthermore, if the upper surface of the translucent resin component is lower than the polishing surface, polishing debris typically enters the recess formed by the translucent resin component and the side of the through-hole, easily adhering and adhering to the surface of the translucent resin component, thus reducing light transmittance over time. However, in the third-type polishing pad of the present invention, since the resin present on the surface of the translucent resin component is grafted with hydrophilic monomers, even if polishing debris enters the recess, the entered polishing debris can flow out along with the slurry to the side of the recess and the groove, easily preventing the polishing debris from adhering and adhering to the surface of the translucent resin component.

[0334] (Through hole)

[0335] A through-hole is a hole that extends from the polishing surface to the opposite side of the polishing pad when viewed from the polishing surface side along the thickness direction of the polishing pad. The through-hole preferably penetrates the polishing layer in a manner parallel to the thickness direction or perpendicular to the polishing surface.

[0336] One through hole can be set in the polishing layer, or two or more through holes can be set separately and independently.

[0337] Examples of through-hole shapes, as seen when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, or the shapes of through-holes in the grinding surface, include: circles, ellipses, triangles, quadrilaterals, hexagons, octagons, etc. Alternatively, a shape formed by the partial overlap of multiple of the above shapes, either identical or different. Among these, a circle is particularly preferred as it does not form corners where grinding debris tends to accumulate.

[0338] (Equivalent circle diameter)

[0339] Within the scope of this specification and claims, the so-called equivalent circle diameter refers to the diameter of a perfect circle whose area is equivalent to that of the figure being measured.

[0340] The equivalent circle diameter of a through hole is the equivalent circle diameter of the through hole when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad. It is equivalent to the diameter when the shape of the through hole is circular when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad.

[0341] There is no particular limitation on the equivalent circle diameter of the through hole, but it is preferably 5 to 40 mm, more preferably 5 to 30 mm, and even more preferably 10 to 28 mm.

[0342] Furthermore, relative to the total area of ​​the grinding surface, the area of ​​the through holes in the grinding surface is preferably 0.003 to 0.5%, more preferably 0.004 to 0.4%, and even more preferably 0.05 to 0.3%.

[0343] (Composition of the polishing layer)

[0344] Examples of resins constituting the abrasive layer include: polyurethane-based resins such as polyurethane and polyurethane-polyurea; acrylic-based resins such as polyacrylate and polyacrylonitrile; ethylene-based resins such as polyvinyl chloride, polyvinyl acetate, and polyvinylidene fluoride; polysulfone-based resins such as polysulfone and polyethersulfone; acylated cellulose-based resins such as acetylated cellulose and butyrylated cellulose; polyamide-based resins; and polystyrene-based resins. Among these, polyurethane resins are more preferred when considering compression properties and flexibility.

[0345] The abrasive layer can be composed of one type of resin or two or more types of resin.

[0346] Furthermore, the abrasive layer preferably has continuous air bubbles. Continuous air bubbles, as referred to here, mean foaming with spaces formed by adjacent air bubbles connected to each other through interconnecting pores. Specifically, it can be a resin obtained by a wet film-forming method or a foam obtained by dry molding or injection molding. Abrasive layers obtained by a wet film-forming method are preferred, as they are expected to exhibit good flexural and tensile properties.

[0347] In this specification, "resin obtained by wet film-forming method" refers to a resin (preferably a polyurethane resin) that forms a film using the wet film-forming method. The wet film-forming method involves dissolving the resin to be formed in an organic solvent, coating the resin solution onto a sheet-like substrate, and then passing it through a coagulation solution to solidify the resin. Resins obtained by wet film-forming typically have multiple teardrop-shaped bubbles (anisotropic, with a shape whose diameter increases from the abrasive surface of the abrasive pad towards the bottom). Therefore, resins obtained by wet film-forming can also be referred to as resins having multiple teardrop-shaped bubbles. The multiple teardrop-shaped bubbles are preferably in the form of continuous bubbles.

[0348] (groove)

[0349] The third-party polishing pad of the present invention preferably has grooves provided on the polishing surface of the polishing layer. The grooves do not penetrate the polishing layer and can be distinguished from through holes.

[0350] Examples of grooves include embossed grooves obtained by embossing the grinding surface and cutting grooves obtained by cutting with a cutting tool. Among these, embossed grooves are preferred. By providing grooves such as embossed grooves, burrs are less likely to form on the grinding surface, and a grinding pad suitable for fine grinding can be obtained.

[0351] The depth of the groove is not particularly limited as long as it is less than the thickness of the abrasive layer, but is preferably 50-90% of the thickness of the abrasive layer, more preferably 60-80%. If the groove disappears due to the grinding of the workpiece, the flowability of the abrasive slurry will be lost, the abrasive performance will decrease, and the abrasive pad will reach the end of its lifespan. Therefore, a deeper groove depth is preferred. On the other hand, to increase the groove depth, it is necessary to increase the processing pressure or processing temperature, which may cause deformation of the substrate (PET) on the back of the abrasive layer or deterioration of the surface of the abrasive layer. If the groove depth is within the above range, these problems are less likely to occur.

[0352] The cross-sectional shape of the grooves is not particularly limited; they can be arc-shaped, U-shaped, V-shaped, rectangular, trapezoidal, or other polygonal shapes, or combinations of two or more of these shapes. Furthermore, there are no particular restrictions on the number or shape of the grooves; they can be adjusted appropriately according to the intended use of the abrasive pad. Examples of shapes include grid-like, radial, concentric, and honeycomb patterns, and combinations thereof are also possible.

[0353] In addition, the third-party abrasive pad of the present invention can be used to form openings on the surface of the abrasive layer by grinding (grinding wheel treatment), or it can be cut.

[0354] In the third-party polishing pad of the present invention, when the polishing surface is set as the upper surface and its opposite surface is set as the lower surface, the grafted surface 9 of the light-transmitting resin member (i.e., the upper surface 4' of the light-transmitting resin member) can be located at a position higher than the lowest part 8' of the groove, at the same position as the lowest part 8', or at a position lower than the lowest part 8'. Preferably, it is located at the same position as the lowest part 8' of the groove or at a position lower than the lowest part 8' of the groove. More preferably, the grafted surface 9 of the light-transmitting resin member is located at a position lower than the lowest part 8' of the groove. Generally, the life of the polishing pad ends when the groove on the polishing surface disappears. However, if the uppermost part of the light-transmitting resin member is located at the same position as the lowest part of the groove or at a position lower than the lowest part of the groove, the polishing pad can be used until the groove disappears.

[0355] Furthermore, in conventional polishing pads, if the upper surface 4' of the light-transmitting resin component is positioned at the same level as or below the lowest part 8' of the groove, the slurry and polishing debris are not easily discharged from the groove, potentially leading to a decrease in light transmittance over time. In contrast, the third-party polishing pad of the present invention, because polishing debris does not easily adhere to or adhere to the surface of the light-transmitting resin component, can suppress the decrease in light transmittance. Moreover, particularly in the polishing pad of one embodiment of the present invention (… Figure 4B or Figure 4C In the grinding pad, even if the grinding debris that enters the recess in the first through hole moves to the side of the first through hole due to the centrifugal force during the grinding process, some of it does not exit from the groove and remains there. It is also not easily seen from the second through hole with a smaller equivalent circle diameter, thus further preventing the reduction of light transmittance. As a result, stable light detection can be performed.

[0356] The third-party abrasive pad of the present invention can be manufactured, for example, by the method described in the item "Method for Manufacturing a Third-Party Abrasive Pad".

[0357] <<Fourth Type of Abrasive Pad>>

[0358] The fourth aspect of the present invention provides an abrasive pad having a light-transmitting resin component and an abrasive layer. The abrasive layer has an abrasive surface for abrading a workpiece. The abrasive pad has a through-hole extending from the abrasive surface to its opposite surface. The light-transmitting resin component is arranged such that, when viewed from the abrasive surface side along the thickness direction of the abrasive pad, the light-transmitting resin component exists within the through-hole. Furthermore, the light-transmitting resin component has, at least on its abrasive surface side, a resin comprising constituent units derived from a polyfunctional (meth)acrylate monomer. The polyfunctional (meth)acrylate monomer has two or more polymerizable functional groups and has a -C group. 2-4 Alkylene-O- unit.

[0359] The following will sometimes include components from functional groups having more than two polymeric functional groups and having -C 2-4 Resins comprising the constituent units of polyfunctional (meth)acrylate monomers with alkylene-O- units are abbreviated as resins containing constituent units derived from polyfunctional (meth)acrylate monomers. Similarly, sometimes resins having two or more polymerizable functional groups and having -C 2-4 Polyfunctional (meth)acrylate monomers with alkylene-O- units are abbreviated as polyfunctional (meth)acrylate monomers.

[0360] Within the scope of this specification and claims, a polishing layer refers to a layer having a surface (polishing surface) that contacts and polishes a workpiece such as a semiconductor device during polishing. The workpiece is not particularly limited; examples include substrates such as product substrates containing multiple memory dies or processor dies, test substrates, bare substrates, and gate substrates. The substrate can be at various stages of integrated circuit manufacturing; for example, the substrate can be a bare wafer, or it can be one or more stacked layers and / or patterning layers.

[0361] Additionally, if referring to Figure 2B , Figure 3B , Figure 4B , Figure 4C , Figure 5B The surface of the light-transmitting resin component at least on the polished side refers to the surface portion 9 on the polished side of the light-transmitting resin component 4 when the polished surface is set as the upper surface and its opposite surface is set as the lower surface.

[0362] <Translucent Resin Components>

[0363] The fourth embodiment of the present invention provides a polishing pad with a light-transmitting resin component, i.e., a window component. By irradiating the workpiece with light through the light-transmitting resin component, the moment when the workpiece reaches the desired surface characteristics and planarity can be detected. Optical endpoint detection uses visible light (white light), such as lasers or lamps.

[0364] The light-transmitting resin component is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component exists within the through-hole. Here, "arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component exists within the through-hole" means that the light-transmitting resin component can be identified when viewed from the grinding surface of the grinding pad along the thickness direction. This concept includes the following situations: (1) such as Figure 2B , Figure 3B As shown, the light-transmitting resin component is connected (or bonded) to the side (sidewall) of the through hole provided in the polishing layer; (2) as Figure 4B or Figure 4C As shown, a layer with through holes is provided below the polishing layer. The through holes have an equivalent circle diameter smaller than that of the through holes in the polishing layer. A light-transmitting resin component is disposed on the exposed portion 7, which is caused by the size difference between the through holes in the polishing layer and the through holes in the other layers; (3) as shown Figure 5B As shown, a light-transmitting resin component is sandwiched between the polished layer and other layers, and is arranged such that a portion of the light-transmitting resin component is exposed within the through-hole. Preferably, it is (1) or (2), more preferably (2).

[0365] As a light-transmitting resin component, there are no particular limitations on the type of resin that allows light to pass through. For example, thermosetting resins such as polyurethane resin, polyester resin, phenolic resin, urea resin, melamine resin, epoxy resin, and acrylic resin can be used; thermoplastic resins such as polyurethane resin, polyester resin, polyamide resin, cellulose resin, acrylic resin, polycarbonate resin, halogen resin (polyvinyl chloride, polytetrafluoroethylene, polyvinylidene fluoride, etc.), polystyrene resin, and olefin resin (polyethylene, polypropylene, etc.); rubbers such as butadiene rubber and isoprene rubber; photocurable resins cured by ultraviolet light, electron beams, etc.; and photosensitive resins. Among these, acrylic resin, polyurethane resin, polyester resin, and polystyrene resin are preferred, and acrylic resin is more preferred. Using these resin components improves the adhesion to resins containing polyfunctional (meth)acrylate monomers as constituent units, making them less prone to peeling.

[0366] There are no particular limitations on the transparent resin component as long as it is a resin with a degree of transparency that allows light to pass through. Preferably, it has a transparency of 60% or more for visible light transmittance (hereinafter referred to as light transmittance) when irradiated with light of wavelengths from 380 nm to 780 nm. More preferably, it has a transparency of 65% or more. Even more preferably, it has a transparency of 70% or more. Even more preferably, it has a transparency of 75% or more. Even more preferably, it has a transparency of 80% or more. The visible light transmittance can be measured by measuring the transmission spectrum of wavelengths from 300 to 1000 nm using a spectrophotometer and determined as the visible light transmittance (%) according to the Japanese Industrial Standard (JIS A5759:2008).

[0367] (Multifunctional (meth)acrylate monomers)

[0368] The abrasive pad of the fourth embodiment of the present invention has a resin comprising constituent units from polyfunctional (meth)acrylate monomers on at least the abrasive surface side of the translucent resin component. The polyfunctional (meth)acrylate monomers have two or more polymerizable functional groups and have -C 2-4 Alkylene-O- unit.

[0369] "has -C" 2-4 "alkylene-O-unit" refers to a unit having one or more -C atoms. 2-4 The basic unit of alkylene is -O-. The case of having one basic unit or multiple repeating basic units can be rewritten as having (-C) 2-4 alkylene-O-) n (n is an integer greater than or equal to 1). There is no particular limitation on the number of basic units or the number of n, but it is preferably 1 to 30, more preferably 2 to 28, even more preferably 3 to 25, and even more preferably 4 to 25.

[0370] Multifunctional (meth)acrylate monomers can have one type of -C 2-4 The alkylene-O- unit can also have more than two different -Cs. 2-4 Alkylene-O- unit.

[0371] -C of each multifunctional (meth)acrylate monomer 2-4 The number of alkylene-O- is preferably 1 to 30, more preferably 2 to 28, even more preferably 3 to 25, and even more preferably 4 to 25.

[0372] -C 2-4 The alkylene-O- unit is preferably -C. 2-3 Alkylene-O- unit. Additionally, -C 2-4The alkylene-O- unit is preferably derived from ethylene oxide (-CH2-CH2-O-) and / or from propylene oxide (-CH2-CH(CH3)-O- or -CH(CH3)-CH2-O- (preferably -CH2-CH(CH3)-O-)). The polyfunctional (meth)acrylate monomer is preferably a polyfunctional (meth)acrylate monomer having a -CH2-CH2-O- unit and / or a -CH2-CH(CH3)-O- unit.

[0373] Multifunctional (meth)acrylate monomers contain -C 2-4 Alkylene-O- unit. -C 2-4 The alkylene-O- unit can exist in any manner in polyfunctional (meth)acrylate monomers, for example, it can be esterified with the carboxyl group of (meth)acrylic acid, or it can be bonded (ester bond, ether bond, etc.) to a group bonded (ester bond, amide bond, etc.) with the carboxyl group of (meth)acrylic acid.

[0374] The light-transmitting resin component may have at least one surface on its grinding surface coated with a resin containing constituent units derived from polyfunctional (meth)acrylate monomers, or the light-transmitting resin component itself may be composed of a resin containing constituent units derived from polyfunctional (meth)acrylate monomers. More preferably, at least one surface on the grinding surface of the light-transmitting resin component is coated with a resin containing constituent units derived from polyfunctional (meth)acrylate monomers. By coating the grinding surface with the aforementioned resin, the wettability of the slurry is improved, and uneven light transmittance caused by the presence of slurry on the surface of the light-transmitting resin component can be suppressed. This allows for more precise determination of the grinding endpoint.

[0375] In addition, the light-transmitting resin component can be coated not only on the surface of the grinding side, but also on the side opposite to the grinding surface (back side) and the side side. However, coating the back side and the side side will increase the cost. On the other hand, coating the back side and the side side is not related to the effect of the present invention. Therefore, it is preferable that only the surface of the grinding side is coated with the resin.

[0376] There is no particular limitation on the thickness of the surface layer of the resin-coated light-transmitting component, but it is preferably 1 to 50 μm. If the thickness of the surface layer is within the above range, a higher light transmittance can be obtained.

[0377] As a polyfunctional (meth)acrylate monomer, it is preferably at least one selected from the group consisting of: (i) having -C 2-4 Monomers formed by esterification of alkylene-O-unit compounds with (meth)acrylic acid; and (ii) compounds with C-... 2-4 Monomers formed by esterification of teratolytic or higher alcohols of epoxides with (meth)acrylic acid.

[0378] As a monomer of (i), it is preferred to have -C 2-3 Monomers formed by esterification of alkylene-O-unit compounds with (meth)acrylic acid.

[0379] As the monomer of (ii), it is preferably a monomer formed by esterification of a ternary or higher alcohol having added ethylene oxide and / or propylene oxide with (meth)acrylic acid.

[0380] The above-mentioned (i) multifunctional (meth)acrylate monomers are as having -C 2-4 Monomers formed by the esterification of alkylene-O-unit compounds with (meth)acrylic acid are those containing a (meth)acryloyl group and a -C group within their molecule. 2-4 Compounds of both alkylene-O- units.

[0381] As the multifunctional (meth)acrylate monomer mentioned in (i) above, a difunctional (meth)acrylate monomer is preferred. Resins containing constituent units derived from difunctional (meth)acrylates exhibit relatively excellent flexibility, thus providing high adhesion to the substrate and preventing peeling.

[0382] The -C of each of the above (i) multifunctional (meth)acrylate monomers 2-4 The number of alkylene-O- is preferably 1 to 30, more preferably 4 to 30, even more preferably 5 to 25, and even more preferably 9 to 25.

[0383] As having -C 2-4 Examples of compounds with alkylene-O- units include compounds formed by combining (poly)ethylene oxide, (poly)propylene oxide, (poly)tetramethylene glycol, diethylene oxide, diethylene oxide, diethylene oxide, ditetramethylene glycol, triethylene oxide, triethylene oxide, triethylene oxide, tritetramethylene glycol, etc., with mono(meth)acrylic acid. Among these, compounds formed by combining (poly)ethylene oxide and / or (poly)propylene oxide with mono(meth)acrylic acid are preferred. By further reacting this compound with other (meth)acrylic acids, multifunctional, preferably difunctional (meth)acrylate monomers can be obtained.

[0384] Examples of monomers mentioned in (i) above include: polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, tetramethylene glycol di(meth)acrylate, etc. (poly)C 2-4 Alkyl glycol di(meth)acrylate, methoxy-(poly)ethylene glycol (meth)acrylate, and other methoxy-(poly)C 2-4 Alkyl glycol di(meth)acrylate. Preferably, (poly)C 2-3Alkyl glycol di(meth)acrylate ((poly)ethylene glycol di(meth)acrylate and / or (poly)propylene glycol di(meth)acrylate), more preferably (poly)ethylene glycol di(meth)acrylate.

[0385]

[0386] (Poly)C 2-3 Alkyl glycol di(meth)acrylate

[0387] (n is an integer of 1 or more, and R1 and R2 are independently hydrogen atoms or methyl groups (preferably hydrogen atoms). R is -CH2-CHR3-O- or -CHR3-CH2-O- (preferably -CH2-CHR3-O-), and R3 is independently a hydrogen atom or a methyl group (preferably hydrogen atom). When n is an integer of 2 or more, two or more Rs may be the same or different. n is preferably 4 to 30, more preferably 9 to 25. The number of n for each monomer is preferably 4 to 30, more preferably 9 to 25.)

[0388] It should be noted that, within the scope of this specification and claims, (poly)ethylene glycol is used as a concept that includes both one ethylene glycol (monoethylene glycol) and two or more ethylene glycols (diethylene glycol, triethylene glycol, tetraethylene glycol, etc.).

[0389] Similarly, (poly)propylene glycol is used as a concept that includes both one propylene glycol (monopropylene glycol) and two or more propylene glycols (dipropylene glycol, tripropylene glycol, tetrapropylene glycol, etc.).

[0390] Similarly, (poly)tetramethylene glycol is used as a concept that includes both one tetramethylene glycol (mono-tetramethylene glycol) and two or more tetramethylene glycols (di-tetramethylene glycol, tri-tetramethylene glycol, tetra-tetramethylene glycol, etc.).

[0391] The mass-average molecular weight of the monomer in (i) above is preferably 200 to 1500, more preferably 300 to 1200, even more preferably 400 to 1400, even more preferably 500 to 1300, and even more preferably 600 to 1200.

[0392] The polyfunctional (meth)acrylate monomers of (ii) above are used as addition reactions with C 2-4 Monomers formed by the esterification of teratolytic or higher alcohols of epoxides with (meth)acrylic acid have (meth)acryloyl groups and -C groups within their molecules. 2-4 Compounds of both alkylene-O- units.

[0393] As the multifunctional (meth)acrylate monomer of (ii) above, a 3- to 6-functional (meth)acrylate monomer is preferred, a 3- to 5-functional (meth)acrylate monomer is more preferred, and a 3- to 4-functional (meth)acrylate monomer is even more preferred. Such a multifunctional (meth)acrylate can increase the curing speed during polymerization, increase the crosslinking density, and help improve water resistance.

[0394] C of each of the above-mentioned (ii) multifunctional (meth)acrylate monomers 2-4 Epoxyalkylene (-C 2-4 The number of basic units (alkylene-O-) is preferably 1 to 30, more preferably 3 to 30, and even more preferably 3 to 25.

[0395] As a triglyceride or higher alcohol, it is preferably selected from at least one of the group consisting of glycerol, diglycerol, triglycerol, trimethylolpropane, di-trimethylolpropane, erythritol, pentaerythritol, and dipentaerythritol; more preferably, it is selected from at least one of the group consisting of glycerol, diglycerol, trimethylolpropane, di-trimethylolpropane, pentaerythritol, and dipentaerythritol; even more preferably, it is selected from at least one of the group consisting of glycerol, pentaerythritol, and trimethylolpropane; and even more preferably, it is selected from at least one of the group consisting of glycerol and pentaerythritol.

[0396] Additionally, C is an added bonus. 2-4 Three or more alcohols of epoxides are preferred, especially those with C-type addition. 2-3 Alcohols of teratoides or higher (ethylene oxide (EO) and / or propylene oxide (PO)).

[0397] As an example of the monomer mentioned in (ii) above, C can be cited: 2-4 Alkoxylated pentaerythritol tetra(meth)acrylate, C 2-4 Alkoxylated glycerol tri(meth)acrylate, C 2-4 Alkoxylated trimethylolpropane tri(meth)acrylate and dipentaerythritol hexaacrylate. Preferably, C... 2-3 Alkoxylated pentaerythritol tetra(meth)acrylate, C 2-3 Alkoxylated glycerol tri(meth)acrylate and / or C 2-3 Alkoxylated trimethylolpropane tri(meth)acrylate, more preferably C 2-3 Alkoxylated pentaerythritol tetra(meth)acrylate and / or C 2-3 Alkoxylated glycerol tri(meth)acrylate.

[0398]

[0399] C 2-3 Alkoxylated pentaerythritol tetra(meth)acrylate

[0400] (l, m, n, o are independently integers of 0 or more (where at least one of l, m, n, o is 1 or more), R1, R2, R3, R4 are independently hydrogen atoms or methyl groups (preferably hydrogen atoms), R5, R6, R7, R8 are each independently -CH2-CHR9-O- or -CHR9-CH2-O- (preferably -CH2-CHR9-O-), and R9 are each independently hydrogen atoms or methyl groups (preferably hydrogen atoms). When l is an integer of 2 or more, two or more R5s can be the same or different. When m is an integer of 2 or more, two or more R6s...) The elements can be the same or different. When n is an integer of 2 or more, two or more R7s can be the same or different. When o is an integer of 2 or more, two or more R8s can be the same or different. l, m, n, and o are preferably integers of 1 or more independently. l+m+n+o is preferably 3 to 35, more preferably 3 to 15, more preferably 4 to 10, more preferably 4 to 6, and even more preferably 4. The number of l+m+n+o for each individual is preferably 3 to 35, more preferably 3 to 15, more preferably 4 to 10, more preferably 4 to 6, and even more preferably 4.

[0401]

[0402] C 2-3 Alkoxylated glycerol tri(meth)acrylate

[0403] (l, m, n are independently integers of 0 or more (where at least one of l, m, n is 1 or more), R1, R2, R3 are independently hydrogen atoms or methyl groups (preferably hydrogen atoms), R4, R5, R6 are each independently -CH2-CHR7-O- or -CHR7-CH2-O- (preferably -CH2-CHR7-O-), and R7 are each independently hydrogen atoms or methyl groups (preferably hydrogen atoms). When l is an integer of 2 or more, two or more R4s may be the same or different. When m is an integer of 2 or more, two or more R5s may be the same or different. When n is an integer of 2 or more, two or more R6s may be the same or different. l, m, n are preferably independently integers of 1 or more. l+m+n is preferably 3 to 30, more preferably 10 to 25, and even more preferably 15 to 25. The number of l+m+n for each monomer is preferably 3 to 30, more preferably 10 to 25, and even more preferably 15 to 25.)

[0404]

[0405] C 2-3 Alkoxylated trimethylolpropane tri(meth)acrylate

[0406] (l, m, n are independently integers of 0 or more (where at least one of l, m, n is 1 or more), R1, R2, R3 are independently hydrogen atoms or methyl groups (preferably hydrogen atoms), R4, R5, R6 are each independently -CH2-CHR7-O- or -CHR7-CH2-O- (preferably -CH2-CHR7-O-), and R7 are each independently hydrogen atoms or methyl groups (preferably hydrogen atoms). When l is an integer of 2 or more, two or more R4s may be the same or different. When m is an integer of 2 or more, two or more R5s may be the same or different. When n is an integer of 2 or more, two or more R6s may be the same or different. l, m, n are preferably independently integers of 1 or more. l+m+n is preferably 3 to 30. The number of l+m+n for each monomer is preferably 3 to 30.)

[0407] The mass-average molecular weight of the monomer in (ii) above is preferably 200 to 2000, preferably 300 to 1500, more preferably 400 to 1300, and even more preferably 500 to 1200.

[0408] As the polyfunctional (meth)acrylate monomers of (i) and (ii) above, preferably at least one is selected from the group consisting of polyethylene glycol diacrylate, polypropylene glycol diacrylate, ethoxylated pentaerythritol tetraacrylate, propoxylated pentaerythritol tetraacrylate, ethoxylated glycerol triacrylate, propoxylated glycerol triacrylate, ethoxylated trimethylolpropane triacrylate, and propoxylated trimethylolpropane triacrylate; more preferably at least one is selected from the group consisting of polyethylene glycol diacrylate, polypropylene glycol diacrylate, ethoxylated pentaerythritol tetraacrylate, propoxylated pentaerythritol tetraacrylate, ethoxylated glycerol triacrylate, and propoxylated glycerol triacrylate; and even more preferably at least one is selected from the group consisting of polyethylene glycol diacrylate, ethoxylated pentaerythritol tetraacrylate, propoxylated pentaerythritol tetraacrylate, and ethoxylated glycerol triacrylate.

[0409] Specific examples of polyfunctional (meth)acrylate monomers that may be preferably used in this invention include: polyethylene glycol diacrylate ("EBECRYL 11" manufactured by DAICEL-ALLNEX, "A-1000" manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), C 2-3 Alkoxylated pentaerythritol tetraacrylate ("EBECRYL 40" manufactured by DAICEL-ALLNEX Co., Ltd.), ethoxylated glycerol triacrylate ("A-GLY-20E" manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), etc.

[0410] Relative to 100 parts by weight of all monomer components constituting the above-described resin, the content of the monomer in the resin containing the constituent unit of the polyfunctional (meth)acrylate monomer is preferably 30 to 100 parts by weight, more preferably 40 to 100 parts by weight, even more preferably 45 to 100 parts by weight, even more preferably 70 to 100 parts by weight, even more preferably 80 to 100 parts by weight, and may also be 100 parts by weight. Relative to 100 parts by weight of all constituent components of the above-described resin, the content of the monomer is also preferably 40 to 60 parts by weight.

[0411] There are no particular limitations on the mass-average molecular weight of resins containing constituent units derived from polyfunctional (meth)acrylate monomers; resins with various mass-average molecular weights can be used. For example, the mass-average molecular weight of the resin can range from 500 to 30,000. If the molecular weight is above 500, high hydrophilicity can be achieved, and sufficient durability can be obtained by increasing the molecular weight during crosslinking. If the molecular weight is below 30,000, the viscosity will not increase excessively, allowing for uniform coating. Alternatively, the mass-average molecular weight of the resin can range from 600 to 20,000, or from 700 to 15,000.

[0412] The polyfunctional (meth)acrylate monomer has two or more polymerizable functional groups. Preferably, the polyfunctional (meth)acrylate monomer has 2 to 6 polymerizable functional groups, more preferably 2 to 5 polymerizable functional groups, and even more preferably 2 to 4 polymerizable functional groups.

[0413] As a polymerizable functional group, it is preferably an ethylene unsaturated double bond (an unsaturated double bond between carbon atoms), and more preferably an ethylene unsaturated double bond (an unsaturated double bond between carbon atoms) present in the (meth)acryloyl group.

[0414] Furthermore, resins containing units derived from polyfunctional (meth)acrylates may further contain units derived from urethane (meth)acrylates. By further including units derived from urethane (meth)acrylates, the adhesion and curing properties of translucent resin components are easily improved. In addition, swelling caused by abrasive slurries is easily suppressed.

[0415] Carbamate (meth)acrylates are compounds having a carbamate bond formed by reacting an isocyanate group with a hydroxyl group and a (meth)acryloyl group. Carbamate (meth)acrylates preferably have two or more polymerizable functional groups, more preferably two to four polymerizable functional groups, even more preferably two to three polymerizable functional groups, and even more preferably two polymerizable functional groups. As polymerizable functional groups, vinyl unsaturated double bonds (unsaturated double bonds between carbon atoms) are preferred, and more preferably vinyl unsaturated double bonds (unsaturated double bonds between carbon atoms) present in the (meth)acryloyl group.

[0416] Examples of urethane (meth)acrylates include, for example, aliphatic urethane (meth)acrylates and aromatic urethane (meth)acrylates. Furthermore, urethane (meth)acrylates preferably do not have a structure derived from polysiloxanes.

[0417] Carbamate (meth)acrylates can be obtained, for example, by reacting a hydroxyl compound having at least two (meth)acryloyl groups with an isocyanate. Examples of such isocyanates include, for instance, aliphatic polyisocyanates or aromatic polyisocyanates.

[0418] Aliphatic carbamate (meth)acrylates can be obtained, for example, by reacting a hydroxyl compound having at least two (meth)acryloyl groups with an aliphatic isocyanate. Examples of such aliphatic isocyanates include, for instance, aliphatic diisocyanates and aliphatic triisocyanates.

[0419] Aromatic carbamate (meth)acrylates can be obtained, for example, by reacting a hydroxyl compound having at least two (meth)acryloyl groups with an aromatic isocyanate. Examples of such aromatic isocyanates include, for instance, aromatic diisocyanates and aromatic triisocyanates.

[0420] When a resin comprising a unit derived from a polyfunctional (meth)acrylate monomer contains a unit derived from a urethane (meth)acrylate, the content of the urethane (meth)acrylate is preferably 70 parts by mass or less, more preferably 60 parts by mass or less, and even more preferably 55 parts by mass or less, relative to 100 parts by mass of all monomer components constituting the resin. Furthermore, the component derived from the urethane (meth)acrylate monomer is preferably 40 to 60 parts by mass relative to 100 parts by mass of all monomer components of the resin.

[0421] There are no particular limitations on the coating method using a resin comprising units derived from the aforementioned polyfunctional (meth)acrylate monomers. For example, it can be carried out by polymerizing the aforementioned polyfunctional (meth)acrylate monomers with other monomers or oligomers (preferably acrylic monomers or oligomers) as needed using conventional methods (solution polymerization, photopolymerization). Photopolymerization is preferred.

[0422] When using solution polymerization, the polymerization reaction can be carried out while the solution containing the aforementioned monomers and polymerization initiators (catalysts, etc.) is applied to the surface of a translucent resin component and dried to obtain a coating.

[0423] In the case of photopolymerization, a solution containing the aforementioned monomers and photopolymerization initiator can be applied to the surface of a translucent resin component and subjected to ultraviolet irradiation to obtain a coating.

[0424] As a photopolymerization initiator, there are no particular restrictions as long as it can cure photocurable resins through irradiation with ultraviolet light, electron beams, etc., and well-known photopolymerization initiators can be used. For example, free radical polymerization initiators, cationic polymerization initiators, and anionic polymerization initiators can be mentioned. As a commercially available product, IRGACURE (manufactured by IGM Resin BV) can be mentioned.

[0425] <Configuration of translucent resin components>

[0426] In the fourth aspect of the abrasive pad of the present invention, when the abrasive surface is set as the upper surface and its opposite surface as the lower surface, the uppermost part of the light-transmitting resin member can be at the same height as the abrasive surface, or it can be lower than the abrasive surface, preferably lower than the abrasive surface. Figure 2B By ensuring the top of the translucent resin component is lower than the grinding surface, it prevents grinding scratches caused by the harder translucent resin component. However, if the top of the translucent resin component is lower than the grinding surface, the slurry enters the recess formed by the translucent resin component and the side of the through-hole. Most of this slurry is moved to the side of the through-hole by centrifugal force and discharged through the groove. This can easily result in some slurry remaining on the surface of the translucent resin component, or none at all. When using conventional grinding pads, the light transmittance differs between cases with some slurry remaining and cases without residue, making it difficult to accurately determine the grinding endpoint. In contrast, the polishing pad of the fourth aspect of the present invention has a better affinity with the slurry because the resin containing the constituent units from the above-mentioned polyfunctional (meth)acrylate monomers exists on the surface of the polishing surface of the light-transmitting resin member. Even in the case of a small amount of slurry, it will spread uniformly on the window surface. As a result, the variation in light transmittance is reduced from the beginning to the end of polishing. Even if the uppermost part of the light-transmitting resin member is in a position lower than the polishing surface, the polishing endpoint can be determined with high accuracy.

[0427] (Pass rate)

[0428] In the fourth aspect of the present invention, the difference between the visible light transmittance (hereinafter referred to as light transmittance) when no water is adhering to the surface of the light-transmitting resin member on the grinding surface side and the visible light transmittance when water is adhering to the surface of the light-transmitting resin member on the grinding surface side is preferably within 10%. By keeping the difference in light transmittance within the above range, it is less likely that a difference in light transmittance will occur between materials with and without slurry on the surface of the light-transmitting resin member, and the determination of the grinding endpoint can be performed with high precision.

[0429] Light transmittance can be measured using a spectrophotometer to measure the transmission spectrum from 300 to 1000 nm, and the result is obtained as the visible light transmittance (%) according to the Japanese Industrial Standard (JIS A5759:2008). Specifically, the transmittance is calculated as follows: the transmittance for each wavelength in the range of 380 to 780 nm is measured, and the transmittance at each wavelength is multiplied by a weighted average obtained from the CIE (International Commission on Illumination) daylight D65 spectral distribution, the CIE light adaptation standard relative visual sensitivity wavelength distribution, and the wavelength intervals.

[0430] In addition, regarding the determination of light transmittance when water is applied to the polished surface of a translucent resin component, a sufficient amount of water (for example, about 0.01 to 0.03 mL for a translucent resin component cut into 9 mm × 50 mm pieces) can be sprayed onto the entire surface of the polished surface of the translucent resin component. The translucent resin component is then placed vertically to the ground for 60 seconds to remove the water, and the resulting translucent resin component is used for measurement.

[0431] (Through hole)

[0432] A through-hole is a hole that extends from the polishing surface to the opposite side of the polishing pad when viewed from the polishing surface side along the thickness direction of the polishing pad. The through-hole preferably penetrates the polishing layer in a manner parallel to the thickness direction or perpendicular to the polishing surface.

[0433] One through hole can be set in the polishing layer, or two or more through holes can be set separately and independently.

[0434] Examples of through-hole shapes, as seen when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, or the shapes of through-holes in the grinding surface, include: circles, ellipses, triangles, quadrilaterals, hexagons, octagons, etc. Alternatively, a shape formed by the partial overlap of multiple of the above shapes, either identical or different. Among these, circles are particularly preferred because they do not form corners where grinding debris tends to accumulate.

[0435] (Equivalent circle diameter)

[0436] Within the scope of this specification and claims, the so-called equivalent circle diameter refers to the diameter of a perfect circle whose area is equivalent to that of the figure being measured.

[0437] The equivalent circle diameter of a through hole is the equivalent circle diameter of the through hole when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad. It is equivalent to the diameter when the shape of the through hole is circular when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad.

[0438] There is no particular limitation on the equivalent circle diameter of the through hole, but it is preferably 5 to 40 mm, more preferably 5 to 30 mm, and even more preferably 8 to 28 mm.

[0439] Furthermore, relative to the total area of ​​the grinding surface, the area of ​​the through holes in the grinding surface is preferably 0.003 to 0.5%, more preferably 0.004 to 0.4%, and even more preferably 0.005 to 0.3%.

[0440] (Composition of the polishing layer)

[0441] Examples of resins constituting the abrasive layer include: polyurethane-based resins such as polyurethane and polyurethane-polyurea; acrylic-based resins such as polyacrylate and polyacrylonitrile; ethylene-based resins such as polyvinyl chloride, polyvinyl acetate, and polyvinylidene fluoride; polysulfone-based resins such as polysulfone and polyethersulfone; acylated cellulose-based resins such as acetylated cellulose and butyrylated cellulose; polyamide-based resins; and polystyrene-based resins. Among these, polyurethane resins are more preferred when considering compression properties and flexibility.

[0442] The abrasive layer can be composed of one type of resin or two or more types of resin.

[0443] Furthermore, the abrasive layer preferably has continuous air bubbles. Continuous air bubbles, as referred to here, mean foaming with spaces formed by adjacent air bubbles connected to each other through interconnecting pores. Specifically, it can be a resin obtained by a wet film-forming method or a foam obtained by dry molding or injection molding. Abrasive layers obtained by a wet film-forming method are preferred, as they are expected to exhibit good flexural and tensile properties.

[0444] In this specification, "resin obtained by wet film-forming method" refers to a resin (preferably a polyurethane resin) that forms a film using the wet film-forming method. The wet film-forming method involves dissolving the resin to be formed in an organic solvent, coating the resin solution onto a sheet-like substrate, and then passing it through a coagulation solution to solidify the resin. Resins obtained by wet film-forming typically have multiple teardrop-shaped bubbles (anisotropic, with a shape whose diameter increases from the abrasive surface of the abrasive pad towards the bottom). Therefore, resins obtained by wet film-forming can also be referred to as resins having multiple teardrop-shaped bubbles. The multiple teardrop-shaped bubbles are preferably in the form of continuous bubbles.

[0445] The abrasive layer of the abrasive pad constituting the fourth aspect of the present invention is preferably a resin sheet (preferably a polyurethane sheet) formed by a wet film-forming method, more preferably a polyurethane sheet containing a plurality of teardrop-shaped bubbles, and even more preferably a polyurethane sheet containing a plurality of teardrop-shaped bubbles and having a continuous bubble formed by connecting part or all of the bubbles through a connecting hole.

[0446] (groove)

[0447] The fourth embodiment of the present invention preferably has grooves on the polishing surface of the polishing layer. The grooves do not penetrate the polishing layer and can be distinguished from through holes.

[0448] Examples of grooves include embossed grooves obtained by embossing the grinding surface and cutting grooves obtained by cutting with a cutting tool. Among these, embossed grooves are preferred. By providing grooves such as embossed grooves, burrs are less likely to form on the grinding surface, and a grinding pad suitable for fine grinding can be obtained.

[0449] The depth of the groove is not particularly limited as long as it is less than the thickness of the abrasive layer, but is preferably 50-90% of the thickness of the abrasive layer, more preferably 60-80%. If the groove disappears due to the grinding of the workpiece, the flowability of the abrasive slurry will be lost, the abrasive performance will decrease, and the abrasive pad will reach the end of its lifespan. Therefore, a deeper groove depth is preferred. On the other hand, to increase the groove depth, it is necessary to increase the processing pressure or processing temperature, which may cause deformation of the substrate (PET) on the back of the abrasive layer or deterioration of the surface of the abrasive layer. If the groove depth is within the above range, these problems are less likely to occur.

[0450] The cross-sectional shape of the grooves is not particularly limited; they can be arc-shaped, U-shaped, V-shaped, rectangular, trapezoidal, or other polygonal shapes, or combinations of two or more of these shapes. Furthermore, there are no particular restrictions on the number or shape of the grooves; they can be adjusted appropriately according to the intended use of the abrasive pad. Examples of shapes include grid-like, radial, concentric, and honeycomb patterns, and combinations thereof are also possible.

[0451] In addition, the abrasive pad of the fourth aspect of the present invention can be opened on the surface of the abrasive layer by grinding (grinding wheel treatment), or it can be cut.

[0452] In the fourth aspect of the abrasive pad of the present invention, when the abrasive surface is set as the upper surface and its opposite surface is set as the lower surface, the uppermost part 4' of the light-transmitting resin member (i.e., the upper surface of the resin containing the constituent units from polyfunctional (meth)acrylate monomers) may be located at a position higher than the lowermost part 8' of the groove, or at the same position as the lowermost part 8', or at a position lower than the lowermost part 8', preferably at the same position as the lowermost part 8' of the groove or at a position higher than the lowermost part 8' of the groove, and more preferably at a position higher than the lowermost part 8' of the groove. Abrasive pad of one aspect of the present invention ( Figure 4B or Figure 4CIn the grinding pad, the slurry and grinding debris that enter the recess in the first through hole move towards the tank due to the centrifugal force during the grinding process, which can prevent the reduction of light transmittance. Furthermore, even after most of the slurry has moved to the tank, only a small amount of slurry remains on the surface of the light-transmitting resin component, which is less likely to cause a reduction in light transmittance due to the slurry, thus enabling stable light detection.

[0453] (advantage)

[0454] The abrasive pad of the fourth embodiment of the present invention has a resin comprising constituent units from polyfunctional (meth)acrylate monomers on at least the abrasive surface side of the light-transmitting member, thereby improving the wettability of the slurry, and the light transmittance hardly changes due to the presence or absence of slurry on the abrasive surface side of the light-transmitting member. Therefore, the abrasive endpoint can be determined with high precision.

[0455] Furthermore, in the polishing pad of the fourth embodiment of the present invention, when the polishing surface is set as the upper surface and its opposite surface as the lower surface, its effect is achieved regardless of whether the surface of the light-transmitting member on the polishing surface side is at the same height as the polishing surface or at a lower position than the polishing surface. In particular, its effect is better when the surface of the light-transmitting member on the polishing surface side is at a lower position than the polishing surface. That is, when the surface of the light-transmitting member on the polishing surface side is at a lower position than the polishing surface, there is a recess (e.g., a cylindrical recess) formed by the surface of the light-transmitting member and the side of the through hole, into which the slurry enters. Most of the slurry entering the recess is moved to the side by centrifugal force and discharged through the embossing groove. Therefore, over time, there may be times when slurry is present in the area through which the laser passes on the surface of the light-transmitting member (times when a large amount of slurry flows into the recess, times when it is not completely discharged, etc.) and times when slurry is not present. The fourth aspect of the present invention provides an abrasive pad that contains a resin comprising constituent units derived from the aforementioned polyfunctional (meth)acrylate monomers on the surface of the abrasive side of the translucent member. This reduces the variation in light transmittance between the case where slurry is attached and the case where slurry is not attached, thereby suppressing uneven light transmittance during the abrasive process.

[0456] Furthermore, the abrasive pad of the fourth aspect of the present invention has chemical resistance and can prevent the deterioration of the transparent resin component, at least on the surface of its abrasive surface, which contains a resin comprising a constituent unit from a polyfunctional (meth)acrylate monomer.

[0457] The abrasive pad of the fourth aspect of the present invention can be manufactured, for example, by the method described in the item "Method for manufacturing an abrasive pad of the fourth aspect".

[0458] <Common Structure of Methods 1 through 4>

[0459] (Shore A hardness)

[0460] In this specification, Shore A hardness means the value measured according to Japanese Industrial Standard (JIS K7311).

[0461] The Shore A hardness of the abrasive layer of the abrasive pad in the first to fourth embodiments of the present invention is preferably 5 to 70 degrees (°), more preferably 8 to 65 degrees. If the Shore A hardness of the abrasive layer is within the above range, excessive contact between abrasive chips and the workpiece can be suppressed, thus reducing the likelihood of scratches.

[0462] Furthermore, in the abrasive pads of the first to fourth embodiments of the present invention, the abrasive layer is preferably softer than the light-transmitting member or the light-transmitting resin member, and more preferably, the Shore A hardness is lower than that of the light-transmitting member or the light-transmitting resin member.

[0463] (Compression ratio and compressive modulus)

[0464] In this specification, compression ratio is an indicator of softness, and compressive modulus is an indicator of the ease with which a material recovers from compression deformation.

[0465] Compression ratio and compressive modulus can be determined according to Japanese Industrial Standard (JIS L1021) using a Schopper-type thickness gauge (compression surface: a circle with a diameter of 1 cm). Details are as follows.

[0466] The thickness t0 is measured 30 seconds after an initial load is applied from the unloaded state. Then, the thickness t1 is measured 5 minutes after a final load is applied from the thickness t0 state. Next, all loads are removed from the thickness t1 state, and the area is left for 5 minutes (set as an unloaded state). The thickness t0' is then measured again 30 seconds after the initial load is applied.

[0467] The compression ratio can be calculated using the formula: Compression Ratio (%) = 100 × (t0 - t1) / t0 (Note that the initial load is 100 g / cm³). 2 The final load is 1120 g / cm. 2 ).

[0468] The compressive modulus can be calculated using the formula: Compressive Modulus (%) = 100 × (t0' - t1) / (t0 - t1) (Note that the initial load is 100 g / cm). 2 The final load is 1120 g / cm. 2 ).

[0469] The compression ratio of the abrasive layer is preferably 1 to 60%, more preferably 3 to 50%. The compressive elastic modulus of the abrasive layer is preferably 50 to 100%, more preferably 60 to 98%. If the compression ratio and compressive elastic modulus are within the above ranges, the abrasive layer is compressed when the workpiece passes through the through hole. Furthermore, due to its excellent recovery after being pressed by the workpiece, the slurry can flow inside the through hole through the bending and stretching motion of the abrasive layer. The slurry circulates without accumulating in the through hole, and the abrasive chips that enter the through hole along with the slurry are easily discharged outside the through hole through the compression and recovery action. Thus, it is easy to prevent the accumulation of abrasive chips in the through hole.

[0470] (thickness)

[0471] The thickness can be determined according to the Japanese Industrial Standard (JIS K6505) using a Schubert-type thickness gauge (pressure surface: a circle with a diameter of 1 cm). Details are as follows.

[0472] Prepare a 10cm square sample, both longitudinally and laterally. Place the sample face up on the measuring instrument. Apply a load of 100g / cm². 2 The pressure surface is lowered onto the sample, and the thickness is measured after 5 seconds. Five measurements are taken for each sample, and the average value is taken as the thickness. It should be noted that if a 10cm square sample cannot be obtained, the average value of 5 measurements is used.

[0473] There is no particular limitation on the thickness of the polishing layer, but it is preferably 0.5 to 2 mm, and more preferably 0.75 to 1.55 mm.

[0474] (Layer other than the polished layer)

[0475] The abrasive pads of the first to fourth embodiments of the present invention may have layers other than the abrasive layer (other layers). These other layers may be one or more layers on the side of the abrasive layer opposite to the abrasive surface. These other layers, like the abrasive layer, have through-holes.

[0476] Furthermore, the through holes in the polishing layer can have the same or different shapes from the through holes in other layers. Preferably, when the polishing pad is viewed from the polishing surface side along the thickness direction, the through holes in the polishing layer at least partially overlap with the through holes in other layers. Thus, when light is irradiated onto the light-transmitting member or the light-transmitting resin member, light will pass through the light-transmitting member or the light-transmitting resin member.

[0477] As one aspect of the present invention, when the polishing pad has other layers, it may have other layers that have through holes (second through holes) with an equivalent circular diameter smaller than the through holes (first through holes) present in the polishing layer. Figure 4A or Figure 4B Other layers are located on the opposite side of the grinding layer from the grinding surface.

[0478] In this type of polishing pad, the first through hole and the second through hole at least partially overlap when viewed from the polishing surface side along the thickness direction. Furthermore, it is preferable that the light-transmitting member or light-transmitting resin member is positioned such that, when viewed from the polishing surface side of the polishing pad along the thickness direction of the polishing pad, the light-transmitting member or light-transmitting resin member is present within the first through hole.

[0479] The polishing pad in this configuration is preferably arranged such that, when viewed from the polishing surface side of the polishing pad along the thickness direction, the outer periphery of the first through hole 5 covers part or all of the outer periphery of the second through hole 6. More preferably, it is arranged such that the outer periphery of the first through hole 5 covers the entire outer periphery of the second through hole 6. Even more preferably, both the first through hole 5 and the second through hole 6 are cylindrical, and the cylindrical central axis of the first through hole 5 coincides with the cylindrical central axis of the second through hole 6 (see reference). Figure 4A or Figure 4B ).

[0480] The outer periphery of the first through hole covers the entire outer periphery of the second through hole, meaning that the diameter of the first through hole 5 is larger than the diameter of the second through hole 6, like a double circle, with the outer periphery of the first through hole 5 existing outside the outer periphery of the second through hole 6.

[0481] Here, when viewed from the grinding surface side along the thickness direction, the first through-hole and the second through-hole at least partially overlap means that, when viewed from the grinding surface side along the thickness direction, the opening positions of the first through-hole and the second through-hole are at least partially consistent. With this type of grinding pad, when viewed along the thickness direction, the first through-hole and the second through-hole are connected along the thickness direction of the grinding pad because their opening positions are at least partially consistent. By ensuring that the positions of the first through-hole and the second through-hole at least partially overlap when viewed from the grinding surface side along the thickness direction, light can be transmitted from the second through-hole side through a light-transmitting member or a light-transmitting resin member disposed within the first through-hole to the first through-hole side, enabling optical detection of the surface condition of the workpiece during the grinding process.

[0482] In this type of abrasive pad, the light-transmitting member 4 or light-transmitting resin member 4 is preferably arranged such that, when viewed from the abrasive surface side along the thickness direction of the abrasive pad, the light-transmitting member 4 or light-transmitting resin member 4 exists within the first through hole 5. Furthermore, the light-transmitting member 4 or light-transmitting resin member 4 is preferably disposed within the first through hole 5.

[0483] Here, the light-transmitting component or light-transmitting resin component is configured such that when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting component or light-transmitting resin component is present in the first through hole. This means that when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting component or light-transmitting resin component can be confirmed.

[0484] Furthermore, when viewing the polishing pad 1 along the thickness direction from the polishing surface side, the first through-hole 5 is preferably arranged such that a portion of the other layer 3 (hereinafter referred to as the exposed portion 7 of the other layer) and at least a portion of the second through-hole 6 are exposed. This allows a light-transmitting member 4 or a light-transmitting resin member 4 to be disposed within the first through-hole 5 and on the second through-hole 6 and exposed portion 7 of the other layer 3. Preferably, when viewing the first through-hole 5 from the polishing surface side, the first through-hole 5 is arranged such that a portion of the other layer 3 and the entire second through-hole 6 are exposed. Additionally, the light-transmitting member 4 or the light-transmitting resin member 4 is preferably disposed within the first through-hole 5 and bonded to the exposed portion 7 of the other layer 3.

[0485] If reference Figure 4A or Figure 4B In the thickness direction cross-section of the polishing pad 1 according to the first to fourth embodiments of the present invention, the first through hole 5 is provided in the polishing layer 2 located on the second through hole 6 and the exposed portion 7. It should be noted that other layers may also be present between the other layers 3 having the exposed portion 7 and the polishing layer 2. In this case, the through hole existing in the other layer preferably has the same cross-sectional shape as the through hole (first through hole) of the polishing layer 2 (cross-sectional shape in the horizontal direction with the polishing surface), and completely overlaps with the first through hole 5 when viewed from the polishing surface along the thickness direction. The light-transmitting member 4 or the light-transmitting resin member 4 is preferably disposed on the second through hole 6 and the exposed portion 7, and disposed inside the first through hole 5 of the polishing layer 2 and the through holes of the other layers.

[0486] One second through hole can be provided in other layers, or two or more through holes can be provided that are separate and independent of each other. The number of first through holes and the number of second through holes are preferably equal. When multiple first through holes and multiple second through holes are provided, each first through hole is preferably provided on each second through hole provided in other layers and its exposed portion.

[0487] The second through hole preferably penetrates other layers in a manner parallel to the thickness direction or perpendicular to the grinding surface.

[0488] When the abrasive pad of the first to fourth embodiments of the present invention is cut in a manner perpendicular to the thickness direction, the cross-sectional shape of the first through hole and the cross-sectional shape of the second through hole may have the same shape or different shapes, preferably having the same shape.

[0489] Examples of the shape of the second through hole when viewed from the abrasive surface side of the abrasive pad along the thickness direction of the abrasive pad, the cross-sectional shape of the second through hole when cut perpendicular to the thickness direction of the abrasive pad, and / or the shape of the second through hole in other layer surfaces include circles, ellipses, triangles, quadrilaterals, hexagons, octagons, and shapes composed of these shapes. Alternatively, it may be a shape formed by the partial overlap of multiple identical or different of the above shapes. Among these, a circle is particularly preferred.

[0490] (Equivalent circle diameter)

[0491] Within the scope of this specification and claims, the equivalent circle diameter of the second through hole is the equivalent circle diameter of the second through hole when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, and is equivalent to the diameter when the shape of the second through hole is circular when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad.

[0492] The equivalent circle diameter of the first through hole is preferably larger than that of the second through hole. As long as the equivalent circle diameter of the first through hole is larger than that of the second through hole, there is no particular limitation on the equivalent circle diameter of the second through hole. The equivalent circle diameter of the second through hole is preferably 1–20 mm, more preferably 2–18 mm, and even more preferably 5–15 mm. Furthermore, there is no particular limitation on the difference between the equivalent circle diameters of the first and second through holes. Preferably, the equivalent circle diameter of the first through hole is 5–30 mm larger than that of the second through hole, more preferably 6–25 mm larger, and even more preferably 7–20 mm larger.

[0493] Furthermore, when viewed from the grinding surface side of the grinding pad along the thickness direction, it is preferable that the outer periphery of the first through hole covers the entire outer periphery of the second through hole, and the equivalent circle diameter of the first through hole is 5 to 30 mm larger than the equivalent circle diameter of the second through hole, more preferably 6 to 25 mm larger, even more preferably 7 to 20 mm larger, even more preferably 8 to 20 mm larger, even more preferably 9 to 20 mm larger, and even more preferably 10 to 20 mm larger.

[0494] Furthermore, when viewed from the grinding surface side of the grinding pad along the thickness direction, it is preferable that the outer periphery of the first through hole covers the entire outer periphery of the second through hole, and the equivalent circle diameter of the first through hole is 1.5 to 4 times, more preferably 2 to 4 times, and even more preferably 2.5 to 3 times, of the equivalent circle diameter of the second through hole.

[0495] Furthermore, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, it is preferable that the shortest distance between the outer periphery of the second through hole and the outer periphery of the first through hole (i.e., the shortest distance between any point on the outer periphery of the second through hole and any point on the outer periphery of the first through hole) is greater than 0, more preferably 2 to 15 mm, even more preferably 3 to 12 mm, and even more preferably 4 to 10 mm.

[0496] If the size difference between the first through-hole and the second through-hole is within the aforementioned range, the slurry and grinding debris entering the recess of the first through-hole will move to the outer periphery of the first through-hole due to the centrifugal force during the grinding process. This makes them less likely to be seen through the second through-hole, which has a smaller equivalent circle diameter. Therefore, it prevents the light path from being blocked by grinding debris when irradiating the light-transmitting component or resin component. Thus, excellent light transmittance can be maintained, and a stable signal intensity for endpoint detection can be obtained during grinding. Furthermore, because the exposed area is sufficiently large, the adhesion strength between the light-transmitting component or resin component and other layers can be maintained, preventing the peeling of the light-transmitting component or resin component.

[0497] Furthermore, even if most of the slurry moves to the side of the recess and only a small amount of slurry remains on the surface of the light-transmitting component or the light-transmitting resin component, the abrasive pads of the first to fourth embodiments of the present invention are less likely to produce uneven light transmittance due to the presence or absence of slurry, thus enabling stable light detection.

[0498] Alternatively, in cases where the abrasive pad of the first to fourth embodiments of the present invention includes other layers, a sheet-like light-transmitting member or a light-transmitting resin member can be sandwiched between the abrasive layer and other layers, arranged such that a portion of the light-transmitting member or light-transmitting resin member is exposed within the through-hole. Figure 5A or Figure 5B At this point, it is preferable that, when viewed from the grinding surface side along the thickness direction, the through-holes (second through-holes) existing in other layers at least partially overlap with the through-holes (first through-holes) existing in the grinding layer, more preferably completely overlap. In this case, the grinding layer preferably has continuous air bubbles containing interconnected holes.

[0499] If the polishing layer has continuous air bubbles containing interconnecting holes, then the continuous air bubbles on the side of the first through-hole in the polishing layer also open, so that a portion of them connects to the polishing surface or the groove area. As a result, the slurry and polishing debris that enter the first through-hole during polishing are moved to the side of the first through-hole by the centrifugal force generated during the polishing process, and are discharged to the polishing surface or the groove area through the continuous air bubbles with interconnecting holes. Therefore, it is possible to prevent the light transmittance from decreasing over time due to the accumulation of polishing debris in the first through-hole, thereby extending the life of the polishing pad.

[0500] Alternatively, in cases where the abrasive pad of the first to fourth embodiments of the present invention includes other layers, through holes may be provided in both the abrasive layer and the other layers disposed below it, and a light-transmitting member or a light-transmitting resin member may be disposed in such a way that it is in contact (or bonded) with the side surface of the through hole of any one or both of them (preferably the side surface of the other layer). Figure 6A or Figure 6B At this point, it is preferable that, when viewed from the polished surface side along the thickness direction, the through-holes (second through-holes) existing in other layers at least partially overlap with the through-holes (first through-holes) existing in the polished layer, more preferably completely overlap. The light-transmitting member or light-transmitting resin member is preferably bonded to the side of the second through-hole. Furthermore, the light-transmitting member or light-transmitting resin member is preferably not present within the first through-hole.

[0501] By bonding transparent components or transparent resin components to the side of the second through-hole in other layers, the thickness of the polishing layer available for polishing is maximized. Even if the polishing surface is ground due to wear during dressing and polishing, the transparent components or transparent resin components will not protrude from the polishing surface, reducing the formation of scratches. Typically, the softer the polishing layer of the polishing pad, the more likely it is to sink due to pressure against the wafer, posing a risk of transparent components or transparent resin components protruding. Polishing pads with protruding components cannot be used for polishing. This type of polishing pad prevents the protrusion of transparent components or transparent resin components, thus achieving a longer polishing pad lifespan. Furthermore, if the light-transmitting component or light-transmitting resin component is bonded to the side of the second through hole rather than to the polishing layer, even if the polishing layer has a telescopic mechanism to easily discharge the polishing debris that has entered the first through hole to the groove and polishing surface, deformation is less likely to occur at the bonding part of the light-transmitting component or light-transmitting resin component, thereby suppressing the peeling of the light-transmitting component or light-transmitting resin component.

[0502] (Composition of other layers)

[0503] Examples of materials constituting other layers include: polyolefin sheets such as polyethylene (PE), polypropylene (PP), and ethylene-propylene copolymer; polyester sheets such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN); vinyl chloride sheets, vinyl acetate sheets, polyimide sheets, polyamide sheets, fluoropolymer sheets, resin-impregnated nonwoven fabrics, nonwoven fabrics, and woven fabrics. Furthermore, the other layers are preferably non-porous sheets from which the slurry does not penetrate. From the viewpoints of physical properties (e.g., dimensional stability, thickness accuracy, processability, tensile strength) and economy, polyester sheets are more preferred for the other layers, and polyethylene terephthalate (PET) sheets are particularly preferred.

[0504] As a method for bonding other layers to the polishing layer or to other layers, for example, a sheet such as a PET sheet coated with adhesive on one or both sides can be used as the other layer, and the other layer can be bonded to the polishing layer or other layers via the adhesive. Alternatively, a sheet such as a PET sheet without adhesive can be prepared as the other layer, and a polishing layer or other layer and an adhesive can be prepared separately, and the other layer can be bonded to the polishing layer or other layers via the adhesive.

[0505] <<Manufacturing Method of Abrasive Pads in the First Method>>

[0506] The method for manufacturing an abrasive pad according to a first aspect of the present invention includes: a step of preparing an abrasive layer and a light-transmitting member having a water contact angle of 80 degrees or less on at least one side; a step of providing a through hole in the abrasive layer; and a step of arranging the light-transmitting member in such a way that the light-transmitting member can be seen in the through hole (here, the light-transmitting member is arranged such that one side of the light-transmitting member becomes the abrasive surface side).

[0507] Each process step is explained.

[0508] <1. Process for preparing a polished layer and a light-transmitting component with a water contact angle of less than 80 degrees on at least one side>

[0509] In this process, a polishing layer is prepared, and a light-transmitting component with a water contact angle of less than 80 degrees on at least one side is prepared.

[0510] The aforementioned abrasive layer and light-transmitting component can be used as the abrasive layer and light-transmitting component, respectively. Both commercially available products and manufactured products can be used. As commercially available light-transmitting components, the following commercially available products can be purchased: "DIAFOIL T910E" and "DIAFOIL T600E" manufactured by Mitsubishi Chemical Corporation, all made of polyester resin; "COSMOSHINE A4300", "COSMOSHINE A2330", "COSMOSHINE TA017", "COSMOSHINE TA015", "COSMOSHINE TA042", "COSMOSHINE TA044", "COSMOSHINE TA048", and "SOFTSHINE TA009" manufactured by Toyobo Corporation; "ACRYPLENHBXN47" and "ACRYPLEN HBS010" manufactured by Mitsubishi Chemical Corporation, all made of polymethyl methacrylate resin; "PANLITE FILM PC-2151" manufactured by Teijin Chemicals Co., Ltd.; and "SUNDUREN SD009" and "SUNDUREN SD009" manufactured by Kaneka Corporation. SD010”; “C000” manufactured by Sumitomo Chemical Co., Ltd., and “IUPILON H-3000” manufactured by Teijin Chemical Co., Ltd., all made of polycarbonate resin; “C001” manufactured by Sumitomo Chemical Co., Ltd., made of acrylic / polycarbonate resin; “S000”, “S001G”, and “S014G” manufactured by Sumitomo Chemical Co., Ltd., and “ACRYPLEN HBS006” manufactured by Mitsubishi Chemical Co., Ltd., all made of acrylic resin; “ZEONOR ZF14” and “ZEONOR ZF16” manufactured by Zeon Corporation, and “ARTONE FILM” manufactured by JSR Corporation, all made of alicyclic polyolefin resin. In the case of manufacturing an abrasive layer, for example, Japanese Patent No. 5421635 and Japanese Patent No. 5844189 can be used to manufacture it by wet-forming a polyurethane resin film and bonding it with a flexible sheet made of PET resin.

[0511] The method for manufacturing the abrasive pad according to the first aspect of the present invention may further include a step of hydrophilicating at least one surface of the light-transmitting member (preferably only the surface on the abrasive surface side). This allows for obtaining a light-transmitting member with a water contact angle of 80 degrees or less on the surface of the abrasive surface side. The above-described method can be cited as an example of the hydrophilication treatment.

[0512] <2. Process of setting through holes in the polishing layer>

[0513] In this process, through holes are provided in the polishing layer. A through hole is a hole that extends from the polishing surface of the polishing layer to its opposite surface. As a method of providing through holes in the polishing layer, for example, through holes can be provided by punching holes along the thickness direction of the polishing layer using a punching die such as a circle, ellipse, or polygon (preferably a circle punching die). By using a punching die, the equivalent circle diameter of the through hole in any cross-section of the polishing layer obtained by cutting the polishing layer of the polishing pad perpendicular to the thickness direction can be the same as the equivalent circle diameter of the through hole in any other cross-section of the polishing layer.

[0514] <3. The procedure of arranging the light-transmitting element in such a way that, when viewed from the polishing surface side of the polishing pad along the thickness direction of the polishing pad, the light-transmitting element exists within the through hole>

[0515] In this process, the light-transmitting member is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member exists within the through hole. At this time, the light-transmitting member is arranged such that one of its surfaces becomes the grinding surface side.

[0516] As a method of arranging a light-transmitting component in such a way that the light-transmitting component exists within the through hole, for example, the following methods can be cited: (1) such as Figure 2A , Figure 3A As shown, a method for arranging a light-transmitting member in such a way that the light-transmitting member is in contact (or bonded) with the side of the through hole provided in the polishing layer; (2) as shown Figure 4A As shown, a method is used where a layer with a through hole having a smaller equivalent circle diameter is provided below the polishing layer, and a light-transmitting member is disposed on the exposed portion caused by the size difference between the through hole of the polishing layer and the through hole of the other layer, thereby distributing the light-transmitting member in such a way that the light-transmitting member can be seen inside the through hole; (3) as Figure 5A As shown, a method of sandwiching a light-transmitting component between the polished layer and other layers, so that a portion of the light-transmitting component is exposed within the through-hole; (4) as shown Figure 6A As shown, a method is used to arrange a light-transmitting member by providing through holes of the same shape in both the polished layer and other layers disposed below it, such that the through holes are connected (or bonded) to the side of the through holes of either or both of them. Among these, (1), (2) or (4) are preferred, (1) or (2) are more preferred, and (2) is even more preferred.

[0517] The method for manufacturing the polishing pad according to the first aspect of the present invention may include a step of preparing a layer other than the polishing layer, and may also include a step of bonding the other layer (another layer) to the polishing layer. The other layer has through holes that are the same as or different from the through holes in the polishing layer. The through holes in the other layer may be provided before bonding the other layer to the polishing layer, or they may be provided after bonding them to the polishing layer. Examples of the other layer and through holes are the same as those described above.

[0518] Alternatively, the method for manufacturing the polishing pad according to the first aspect of the present invention may also include a step of providing a second through hole having an equivalent circular diameter smaller than the through hole (first through hole) of the polishing layer in other layers.

[0519] When using the abrasive pad of the first aspect of the present invention, the abrasive pad is mounted on the abrasive platform of the abrasive machine with the abrasive surface of the abrasive layer facing the workpiece. Then, while supplying slurry, the abrasive platform is rotated to abrade the workpiece surface.

[0520] Examples of workpieces that can be polished using the polishing pad of the first aspect of the present invention include bare silicon and semiconductor devices. The polishing pad of the first aspect of the present invention is particularly suitable for polishing semiconductor devices, especially for fine polishing.

[0521] As a slurry, any water-containing slurry (aqueous slurry) can be used without particular restrictions. Examples include colloidal silica slurry and cerium oxide slurry.

[0522] Using the polishing pad of the first aspect of the present invention, for example, in a CMP polishing process, a light beam passes through a light-transmitting member in a through hole, passes through the polishing pad, and irradiates the wafer. The interference signal generated by the reflection is monitored, thereby enabling optical detection of the moment when the surface characteristics and planar state of the workpiece, such as a semiconductor wafer, are reached while polishing the workpiece.

[0523] <<Second Method for Manufacturing Abrasive Pads>>

[0524] The second aspect of the present invention includes a method for manufacturing an abrasive pad comprising: a step of preparing at least one light-transmitting member having a surface coated with a hydrophilic resin and an abrasive layer; a step of providing a through hole in the abrasive layer; and a step of arranging the light-transmitting member such that, when viewed from the abrasive surface side of the abrasive pad along the thickness direction of the abrasive pad, the light-transmitting member exists within the through hole (here, the coated surface of the light-transmitting member is arranged such that the abrasive surface side is the abrasive surface side).

[0525] Each process step is explained.

[0526] <1. The process of preparing at least one translucent component with a hydrophilic resin coating and an abrasive layer>

[0527] In this process, a translucent component with at least one side coated with a hydrophilic resin and a polishing layer are prepared.

[0528] The abrasive layer, the light-transmitting component, and the hydrophilic resin described above can be used as the abrasive layer, the light-transmitting component, and the hydrophilic resin, respectively. Both the abrasive layer and the light-transmitting component can be commercially available or manufactured products. As commercially available light-transmitting components, the following commercially available products can be purchased: "DIAFOIL T910E" and "DIAFOIL T600E" manufactured by Mitsubishi Chemical Corporation, all made of polyester resin; "COSMOSHINE A4300", "COSMOSHINE A2330", "COSMOSHINE TA017", "COSMOSHINE TA015", "COSMOSHINE TA042", "COSMOSHINE TA044", "COSMOSHINE TA048", and "SOFTSHINE TA009" manufactured by Toyobo Corporation; "ACRYPLEN HBXN47" and "ACRYPLEN HBS010" manufactured by Mitsubishi Chemical Corporation, all made of polymethyl methacrylate resin; "PANLITE FILM PC-2151" manufactured by Teijin Chemicals Co., Ltd.; and "SUNDUREN SD009" and "SUNDUREN SD009" manufactured by Kaneka Corporation. SD010”; “C000” manufactured by Sumitomo Chemical Co., Ltd. and “IUPILON H-3000” manufactured by Teijin Chemical Co., Ltd., both made of polycarbonate resin; “C001” manufactured by Sumitomo Chemical Co., Ltd., both made of acrylic / polycarbonate resin; “S000”, “S001G”, and “S014G” manufactured by Sumitomo Chemical Co., Ltd. and “ACRYPLEN HBS006” manufactured by Mitsubishi Chemical Co., Ltd., both made of acrylic resin; “ZEONOR ZF14” and “ZEONOR ZF16” manufactured by Zeon Corporation of Japan and “ARTONE FILM” manufactured by JSR Corporation, both made of alicyclic polyolefin resin. In the case of manufacturing an abrasive layer, for example, Japanese Patent No. 5421635 and Japanese Patent No. 5844189 can be used to manufacture it by wet-forming a polyurethane resin film and bonding it with a flexible sheet made of PET resin.

[0529] The second aspect of the present invention can further include a step of coating at least one side (preferably only the surface of the grinding side) of the light-transmitting member with a hydrophilic resin.

[0530] There are no particular limitations on the method of coating at least one side of a light-transmitting component with a hydrophilic resin. For example, the resin can be coated onto the surface of the light-transmitting component by means of polymerization reaction, photocuring reaction, etc.

[0531] In the case of utilizing a photocuring reaction, a hydrophilic resin is simply mixed with a photocurable resin and a photopolymerization initiator, coated onto the surface of a translucent component, and then cured by irradiation with ultraviolet light or the like. Examples of photocurable resins and photopolymerization initiators include the aforementioned ones.

[0532] <2. Process of setting through holes in the polishing layer>

[0533] In this process, through holes are provided in the polishing layer. A through hole is a hole that extends from the polishing surface of the polishing layer to its opposite surface. As a method of providing through holes in the polishing layer, for example, through holes can be provided by punching holes along the thickness direction of the polishing layer using a punching die such as a circle, ellipse, or polygon (preferably a circle punching die). By using a punching die, the equivalent circle diameter of the through hole in any cross-section of the polishing layer obtained by cutting the polishing layer of the polishing pad perpendicular to the thickness direction can be the same as the equivalent circle diameter of the through hole in any other cross-section of the polishing layer.

[0534] <3. The procedure of arranging the light-transmitting element in such a way that, when viewed from the polishing surface side of the polishing pad along the thickness direction of the polishing pad, the light-transmitting element exists within the through hole>

[0535] In this process, the light-transmitting component is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting component exists within the through-hole. At this time, it is arranged such that the coating surface of the light-transmitting component is the grinding surface side.

[0536] As a method of arranging a light-transmitting component in such a way that the light-transmitting component exists within the through hole, for example, the following methods can be cited: (1) such as Figure 2B , Figure 3B As shown, a method for arranging a light-transmitting member in such a way that the light-transmitting member is in contact (or bonded) with the side of the through hole provided in the polishing layer; (2) as shown Figure 4B or Figure 4C As shown, a method is used where a layer with a through hole having a smaller equivalent circle diameter is provided below the polishing layer, and a light-transmitting member is disposed on the exposed portion caused by the size difference between the through hole of the polishing layer and the through hole of the other layer, thereby distributing the light-transmitting member in such a way that the light-transmitting member can be seen inside the through hole; (3) as Figure 5B As shown, a method of sandwiching a light-transmitting component between the polished layer and other layers, so that a portion of the light-transmitting component is exposed within the through-hole; (4) as shown Figure 6BAs shown, a method is used to arrange a light-transmitting member by providing through holes of the same shape in both the polished layer and other layers disposed below it, such that the through holes are connected (or bonded) to the side of the through holes of either or both of them. Among these, (1), (2) or (4) are preferred, (1) or (2) are more preferred, and (2) is even more preferred.

[0537] The method for manufacturing the polishing pad according to the second aspect of the present invention may include a step of preparing layers other than the polishing layer, and may also include a step of bonding the layers other than the polishing layer (other layers) to the polishing layer. The other layers have through holes that are the same as or different from the through holes in the polishing layer. The through holes in the other layers may be provided before bonding the other layers to the polishing layer, or they may be provided after bonding them to the polishing layer. Examples of other layers and through holes are the same as those described above.

[0538] Alternatively, the method for manufacturing the polishing pad according to the second aspect of the present invention may also include a step of providing a second through hole having an equivalent circular diameter smaller than that of the through hole (first through hole) of the polishing layer in other layers.

[0539] When using the abrasive pad according to the second aspect of the present invention, the abrasive pad is mounted on the abrasive platform of the abrasive machine with the abrasive surface of the abrasive layer facing the workpiece. Then, while supplying slurry, the abrasive platform is rotated to abrade the workpiece surface.

[0540] Examples of workpieces that can be polished using the polishing pad of the second aspect of the present invention include bare silicon and semiconductor devices. The polishing pad of the second aspect of the present invention is particularly suitable for polishing semiconductor devices, especially for fine polishing, and is therefore preferred.

[0541] As a slurry, any water-containing slurry (aqueous slurry) can be used without particular restrictions. Examples include colloidal silica slurry and cerium oxide slurry.

[0542] Using the polishing pad of the second aspect of the present invention, for example, in a CMP polishing process, a light beam passes through a light-transmitting member in a through hole, passes through the polishing pad, and irradiates the wafer. The interference signal generated by the reflection is monitored, thereby enabling optical detection of the moment when the surface characteristics and planar state of the workpiece are reached while polishing the workpiece.

[0543] <<Third-Party Abrasive Pad Manufacturing Methods>>

[0544] The third-party method for manufacturing a polishing pad according to the present invention is a method for manufacturing a polishing pad according to any one of claims 1 to 10, comprising: a step of preparing a polishing layer and a light-transmitting resin member on at least one surface grafted with a hydrophilic monomer; a step of providing a through hole in the polishing layer; and a step of arranging the light-transmitting resin member in such a way that, when viewed from the polishing surface side of the polishing pad along the thickness direction of the polishing pad, the light-transmitting resin member exists within the through hole (here, the grafted surface of the light-transmitting resin member is arranged such that the polishing surface side is the polishing surface side).

[0545] Each process step is explained.

[0546] <1. Steps for preparing the polishing layer and the transparent resin component with hydrophilic monomers grafted onto at least one surface>

[0547] In this process, a polishing layer and a translucent resin component grafted with a hydrophilic monomer on at least one surface are prepared.

[0548] Within the scope of this specification and claims, "grafted with a hydrophilic monomer on at least one face" means a translucent resin in which the hydrophilic monomer is bound to at least one face by graft polymerization.

[0549] As a translucent resin component, it is preferable to graft a hydrophilic monomer onto only one surface.

[0550] The aforementioned abrasive layer and light-transmitting resin component can be used as the abrasive layer and light-transmitting resin component, respectively. Both commercially available products and manufactured products can be used. As commercially available translucent resin components, the following products can be purchased: "DIAFOIL T910E" and "DIAFOIL T600E" manufactured by Mitsubishi Chemical Corporation, all made of polyester resin; "COSMOSHINE A4300", "COSMOSHINE A2330", "COSMOSHINE TA017", "COSMOSHINE TA015", "COSMOSHINE TA042", "COSMOSHINETA044", "COSMOSHINE TA048", and "SOFTSHINE TA009" manufactured by Toyobo Corporation; "ACRYPLEN HBXN47" and "ACRYPLEN HBS010" manufactured by Mitsubishi Chemical Corporation, all made of polymethyl methacrylate resin; "PANLITE FILM PC-2151" manufactured by Teijin Chemicals Co., Ltd.; and "SUNDUREN SD009" and "SUNDUREN SD009" manufactured by Kaneka Corporation. SD010”; “C000” manufactured by Sumitomo Chemical Co., Ltd. and “IUPILON H-3000” manufactured by Teijin Chemical Co., Ltd., both made of polycarbonate resin; “C001” manufactured by Sumitomo Chemical Co., Ltd., both made of acrylic / polycarbonate resin; “S000”, “S001G”, and “S014G” manufactured by Sumitomo Chemical Co., Ltd. and “ACRYPLEN HBS006” manufactured by Mitsubishi Chemical Co., Ltd., both made of acrylic resin; “ZEONOR ZF14” and “ZEONOR ZF16” manufactured by Zeon Corporation of Japan and “ARTONE FILM” manufactured by JSR Corporation, both made of alicyclic polyolefin resin. In the case of manufacturing an abrasive layer, for example, Japanese Patent No. 5421635 and Japanese Patent No. 5844189 can be used to manufacture it by wet-forming a polyurethane resin film and bonding it with a flexible sheet made of PET resin.

[0551] The third-party method for manufacturing the abrasive pad of the present invention may further include a step of performing plasma grafting treatment on at least one surface of the translucent resin component. The method described above can be cited as an example of plasma grafting treatment. By performing plasma grafting treatment on at least one surface of the translucent resin component, a translucent resin component with hydrophilic monomers grafted and polymerized on at least one surface can be obtained.

[0552] <2. Process of setting through holes in the polishing layer>

[0553] In this process, through holes are provided in the polishing layer. A through hole is a hole that extends from the polishing surface of the polishing layer to its opposite surface. As a method of providing through holes in the polishing layer, for example, through holes can be provided by punching holes along the thickness direction of the polishing layer using a punching die such as a circle, ellipse, or polygon (preferably a circle punching die). By using a punching die, the equivalent circle diameter of the through hole in any cross-section of the polishing layer obtained by cutting the polishing layer of the polishing pad perpendicular to the thickness direction can be the same as the equivalent circle diameter of the through hole in any other cross-section of the polishing layer.

[0554] <3. The process of arranging the light-transmitting resin component in such a way that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component exists within the through-hole.>

[0555] In this process, the light-transmitting resin component is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component exists within the through-hole. At this time, the grafted surface of the light-transmitting resin component is arranged so that the grinding surface side is the same.

[0556] As a method for arranging a light-transmitting resin component in such a way that the light-transmitting resin component exists within the through hole, for example, the following methods can be cited: (1) such as Figure 2B , Figure 3B As shown, a method for arranging a light-transmitting resin component in such a way that the light-transmitting resin component is in contact (or bonded) with the side of the through hole provided in the polishing layer; (2) as shown Figure 4B or Figure 4C As shown, a method is used to arrange a light-transmitting resin component in a manner such that the light-transmitting resin component can be seen within the through-hole, with the through-hole having a smaller equivalent circular diameter, provided below the polishing layer. A light-transmitting resin component is disposed on the exposed portion resulting from the size difference between the through-hole in the polishing layer and the through-hole in the other layer; (3) as shown. Figure 5B As shown, a method of sandwiching a light-transmitting resin component between the polished layer and other layers, so that a portion of the light-transmitting resin component is exposed within the through hole; (4) as shown Figure 6B As shown, a method is used to arrange a translucent resin component in which through holes of the same shape are provided in both the polishing layer and other layers provided below it, and the through holes are connected (or bonded) to the side of the through holes of either or both. Among these, (1), (2) or (4) are preferred, (1) or (2) are more preferred, and (2) is even more preferred.

[0557] The manufacturing method of the third-party polishing pad of the present invention may include a step of preparing layers other than the polishing layer, and may also include a step of bonding the layers other than the polishing layer (other layers) to the polishing layer. The other layers have through holes that are the same as or different from the through holes in the polishing layer. The through holes in the other layers may be provided before bonding the other layers to the polishing layer, or they may be provided after bonding them to the polishing layer. Examples of other layers and through holes are the same as those described above.

[0558] In addition, the third-party method for manufacturing the polishing pad of the present invention may also include a step of providing a second through hole having an equivalent circular diameter smaller than the through hole (first through hole) of the polishing layer in other layers.

[0559] When using the third-party type abrasive pad of the present invention, the abrasive pad is mounted on the abrasive platform of the abrasive machine with the abrasive surface of the abrasive layer facing the workpiece. Then, while supplying slurry, the abrasive platform is rotated to abrade the workpiece surface.

[0560] Examples of workpieces that can be polished using the third-party polishing pad of the present invention include bare silicon and semiconductor devices. The third-party polishing pad of the present invention is particularly suitable for polishing semiconductor devices, especially for fine polishing, and is therefore preferred.

[0561] As a slurry, any water-containing slurry (aqueous slurry) can be used without particular restrictions. Examples include colloidal silica slurry and cerium oxide slurry.

[0562] Using the third-party polishing pad of the present invention, for example, in the CMP polishing process, a light beam passes through a light-transmitting resin component in a through hole, passes through the polishing pad, and irradiates the wafer. The interference signal generated by the reflection is monitored, thereby enabling optical detection of the moment when the surface characteristics and planar state of the workpiece are reached while polishing the workpiece.

[0563] <<Fourth Method for Manufacturing Abrasive Pads>>

[0564] The fourth aspect of the present invention provides a method for manufacturing an abrasive pad comprising: preparing an abrasive layer and a step of having a translucent resin member having on at least one side a resin comprising constituent units derived from a polyfunctional (meth)acrylate monomer, wherein the polyfunctional (meth)acrylate monomer has two or more polymerizable functional groups and has -C 2-4Alkylene-O- unit; a process of providing through holes in the polishing layer; and a process of arranging the light-transmitting resin member in such a way that, when viewed from the polishing surface side of the polishing pad along the thickness direction of the polishing pad, the light-transmitting resin member exists within the through holes (here, the light-transmitting resin member is arranged such that the surface of the resin having the constituent unit containing the polyfunctional (meth)acrylate monomer is the polishing surface side).

[0565] Each process step is explained.

[0566] <1. Prepare a polishing layer and have at least one side containing polymeric functional groups having two or more polymeric functional groups and having -C 2-4 Processing of resins containing alkylene-O-unit polyfunctional (meth)acrylate monomers as constituent units, resulting in translucent resin components.

[0567] In this process, it is prepared that at least one facet contains functional groups having two or more polymerizable functional groups and having -C 2-4 Translucent resin components and abrasive layers of resins comprising polyfunctional (meth)acrylate monomers with alkylene-O-units.

[0568] The abrasive layer, the light-transmitting resin component, and the resin containing constituent units derived from polyfunctional (meth)acrylate monomers can all be described above. Both commercially available products and manufactured products can be used for the abrasive layer and the light-transmitting resin component. As commercially available translucent resin components, the following products can be purchased: "DIAFOIL T910E" and "DIAFOIL T600E" manufactured by Mitsubishi Chemical Corporation, all made of polyester resin; "COSMOSHINE A4300", "COSMOSHINE A2330", "COSMOSHINE TA017", "COSMOSHINE TA015", "COSMOSHINET A042", "COSMOSHINE TA044", "COSMOSHINE TA048", and "SOFTSHINE TA009" manufactured by Toyobo Corporation; "ACRYPLEN HBXN47" and "ACRYPLEN HBS010" manufactured by Mitsubishi Chemical Corporation, all made of polymethyl methacrylate resin; "PANLITE FILM PC-2151" manufactured by Teijin Chemicals Co., Ltd.; and "SUNDURENSD009" and "SUNDUREN" manufactured by Kaneka Corporation. SD010”; “C000” manufactured by Sumitomo Chemical Co., Ltd. and “IUPILON H-3000” manufactured by Teijin Chemical Co., Ltd., both made of polycarbonate resin; “C001” manufactured by Sumitomo Chemical Co., Ltd., made of acrylic / polycarbonate resin; “S000”, “S001G”, and “S014G” manufactured by Sumitomo Chemical Co., Ltd. and “ACRYPLEN HBS006” manufactured by Mitsubishi Chemical Co., Ltd., both made of acrylic resin; “ZEONOR ZF14” and “ZEONOR ZF16” manufactured by Zeon Corporation of Japan and “ARTONE FILM” manufactured by JSR Corporation, both made of alicyclic polyolefin resin. In the case of manufacturing an abrasive layer, for example, Japanese Patent No. 5421635 and Japanese Patent No. 5844189 can be used to manufacture it by wet-forming a polyurethane resin film and bonding it with a flexible sheet made of PET resin.

[0569] The method for manufacturing the abrasive pad according to the fourth aspect of the present invention may further include a step of coating at least one side of a translucent resin component with a resin comprising constituent units derived from polyfunctional (meth)acrylate monomers.

[0570] There are no particular limitations on the method of coating at least one side of the translucent resin component with the above-mentioned resin. For example, the above-mentioned resin can be coated on the surface of the translucent resin component by means of polymerization reaction or photocuring reaction.

[0571] In the case of utilizing a photocuring reaction, the above-mentioned resin is simply mixed with a photocurable resin and a photopolymerization initiator, coated onto the surface of a translucent resin component, and then cured by irradiation with ultraviolet light or the like. Examples of the above-mentioned photocurable resin and photopolymerization initiator can be cited as the photocurable resin and photopolymerization initiator.

[0572] Therefore, the method for manufacturing the abrasive pad according to the fourth aspect of the present invention may further include a step of coating a mixture containing a monomer component comprising a polyfunctional (meth)acrylate monomer and a photopolymerization initiator onto a translucent resin component, and a step of photopolymerizing the mixture.

[0573] <2. Process of setting through holes in the polishing layer>

[0574] In this process, through holes are provided in the polishing layer. A through hole is a hole that extends from the polishing surface of the polishing layer to its opposite surface. As a method of providing through holes in the polishing layer, for example, through holes can be provided by punching holes along the thickness direction of the polishing layer using a punching die such as a circle, ellipse, or polygon (preferably a circle punching die). By using a punching die, the equivalent circle diameter of the through hole in any cross-section of the polishing layer obtained by cutting the polishing layer of the polishing pad perpendicular to the thickness direction can be the same as the equivalent circle diameter of the through hole in any other cross-section of the polishing layer.

[0575] <3. The process of arranging the light-transmitting resin component in such a way that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component exists within the through-hole.>

[0576] In this process, the light-transmitting resin component is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting resin component exists within the through-hole. At this time, the surface of the light-transmitting resin component having the resin containing the constituent units from polyfunctional (meth)acrylate monomers is arranged such that the grinding surface side is the surface of the light-transmitting resin component.

[0577] As a method for arranging a light-transmitting resin component in such a way that the light-transmitting resin component exists within the through hole, for example, the following methods can be cited: (1) such as Figure 2B , Figure 3B As shown, a method for arranging a light-transmitting resin component in such a way that the light-transmitting resin component is in contact (or bonded) with the side of the through hole provided in the polishing layer; (2) as shown Figure 4B or Figure 4CAs shown, a method is used to arrange a light-transmitting resin component in a manner such that the light-transmitting resin component can be seen within the through-hole, with the through-hole having a smaller equivalent circular diameter, provided below the polishing layer. A light-transmitting resin component is disposed on the exposed portion resulting from the size difference between the through-hole in the polishing layer and the through-hole in the other layer; (3) as shown. Figure 5B As shown, a method is used to sandwich a light-transmitting resin component between a polished layer and other layers, so that a portion of the light-transmitting resin component is exposed within a through-hole. Preferably, method (1) or (2), more preferably method (2).

[0578] Furthermore, the method for manufacturing the polishing pad according to the fourth aspect of the present invention may include a step of preparing layers other than the polishing layer, and may also include a step of bonding layers other than the polishing layer (other layers) to the polishing layer. The other layers have through holes that are the same as or different from the through holes in the polishing layer. The through holes in the other layers may be provided before bonding the other layers to the polishing layer, or they may be provided after bonding them to the polishing layer. Examples of other layers and through holes are the same as those described above.

[0579] In addition, the method for manufacturing the polishing pad according to the fourth aspect of the present invention may also include a step of providing a second through hole having an equivalent circular diameter smaller than the through hole (first through hole) of the polishing layer in other layers.

[0580] When using the abrasive pad according to the fourth aspect of the present invention, the abrasive pad is mounted on the abrasive platform of the abrasive machine with the abrasive surface of the abrasive layer facing the workpiece. Then, while supplying slurry, the abrasive platform is rotated to abrade the workpiece surface.

[0581] Examples of workpieces that can be polished using the polishing pad of the fourth aspect of the present invention include bare silicon and semiconductor devices. The polishing pad of the fourth aspect of the present invention is particularly suitable for polishing semiconductor devices, especially for fine polishing, and is therefore preferred.

[0582] As a slurry, any water-containing slurry (aqueous slurry) can be used without particular restrictions. Examples include colloidal silica slurry and cerium oxide slurry.

[0583] Using the polishing pad of the fourth aspect of the present invention, for example, in a CMP polishing process, a light beam passes through a light-transmitting resin component in a through hole, passes through the polishing pad, and irradiates the wafer. The interference signal generated by the reflection is monitored, thereby enabling optical detection of the moment when the surface characteristics and planar state of the workpiece are reached while polishing the workpiece.

[0584] Example

[0585] The present invention will be further described in detail below by way of examples, but the present invention is not limited to these examples.

[0586] <<First-Type Abrasive Pad>>

[0587] [Example 1-1]

[0588] A 20cm x 20cm transparent acrylic resin film (manufactured by Mitsubishi Chemical Co., Ltd., ACRYPLEN HBS006, 150μm thick) was prepared and hydrophilicated by plasma processing on one side. This yielded the light-transmitting component of Example 1-1.

[0589] [Examples 1-2]

[0590] A 20cm x 20cm transparent acrylic resin film (manufactured by Mitsubishi Chemical Co., Ltd., ACRYPLEN HBS006, 150μm thick) was prepared and hydrophilicated by roller blasting one side. This yielded the light-transmitting components of Examples 1-2.

[0591] [Comparative Example 1-1]

[0592] A 20cm x 20cm transparent acrylic resin film (manufactured by Mitsubishi Chemical Co., Ltd., ACRYPLEN HBS006, thickness 150μm) was prepared as the light-transmitting component of Comparative Example 1-1.

[0593] <Water Contact Angle Measurement>

[0594] The water contact angles of the light-transmitting components of Examples 1-1 to 1-2 and Comparative Example 1-1 were measured using an automatic contact angle meter, DropMaster DM500 (manufactured by Kyowa Interface Science Co., Ltd.), by the following method.

[0595] (1) Fill the syringe with distilled water and install the dispensing device, set it to DM500.

[0596] (2) Cut the test sample into 5mm×50mm size and attach it to the stage.

[0597] (3) Start the analysis software, select the contact angle measurement [droplet method], and set the parameters.

[0598] Waiting time before measurement: 1000ms

[0599] Measurement time interval: 1000ms

[0600] Number of consecutive measurements: 180

[0601] (4) Set the measured droplet volume, the position of the injection needle on the image monitor, and optimize the focus value of the image monitor.

[0602] (5) Drop the liquid onto the sample, start the measurement, and read the water contact angle 20 seconds after the start of the measurement.

[0603] The results of the water contact angle measurement test are shown in Table 1.

[0604] <Transmittance Measurement>

[0605] The visible light transmittance of the light-transmitting components of Examples 1-1 to 1-2 and Comparative Example 1-1 was measured using a V-770 UV-Vis-NIR spectrophotometer (manufactured by Nippon Spectrophotometer Co., Ltd.) by the following method. It should be noted that the visible light transmittance was measured under two conditions: with water adhering to the surface of the light-transmitting component (the processed surface in Examples 1-1 to 1-2) and without water adhering to it.

[0606] 1. Measurement under conditions of adhering water

[0607] (1) Place it in a quartz glass trough and measure the blank group.

[0608] (2) Cut the light-transmitting components of Examples 1-1 to 1-2 and Comparative Example 1-1 into sizes of 9mm × 50mm.

[0609] (3) Place the translucent component on a Kimwipe (lens paper) and spray it three times with purified water from a distance of 20 cm using a spray method (50 ml capacity, PP bottle). The spray amount is approximately 0.160–0.165 ml per spray, and the coating amount on the surface of the translucent component after three sprays is approximately 0.01–0.03 ml. After spraying, let the translucent component stand vertically for 60 seconds. Place the translucent component in the quartz glass tank with the unsprayed, water-covered surface in contact with the inner surface of the quartz glass tank.

[0610] (3) With the surface treated surface facing away from the light source, the light-transmitting component is placed on the inner wall of the quartz glass tank in such a way that its entire surface contacts the light source side of the quartz tank.

[0611] (4) The linear transmittance of light relative to 250nm to 1000nm was measured using a UV-Vis-NIR spectrophotometer V-770 (manufactured by Japan Spectrophotometer Co., Ltd.).

[0612] (5) Based on JIS A5759:2008, the visible light transmittance relative to wavelengths of 380–780 nm was calculated.

[0613] 2. Measurement without adhering water

[0614] (1) Place it in a quartz glass trough and measure the blank group.

[0615] (2) Cut the light-transmitting components of Examples 1-1 to 1-2 and Comparative Example 1-1 into sizes of 9mm × 50mm.

[0616] (3) With the surface treated surface facing away from the light source, the light-transmitting component is placed on the inner wall of the quartz glass tank in such a way that its entire surface contacts the light source side of the quartz tank.

[0617] (4) The linear transmittance of light relative to 250nm to 1000nm was measured using a UV-Vis-NIR spectrophotometer V-770 (manufactured by Japan Spectrophotometer Co., Ltd.).

[0618] (5) Based on JIS A5759:2008, the visible light transmittance relative to wavelengths of 380–780 nm was calculated.

[0619] Using the methods described above, the visible light transmittance of the light-transmitting components of Examples 1-1 to 1-2 and Comparative Example 1-1 was determined when the surface was covered with water and when it was not. The results are shown in Table 1.

[0620] [Table 1]

[0621]

[0622] In Comparative Example 1-1, the water contact angle of the surface of the light-transmitting component is greater than 80 degrees, resulting in a significant difference in visible light transmittance between the presence and absence of water on the surface. On the other hand, the water contact angle of the surface of the light-transmitting components of Examples 1-1 to 1-2 is less than 80 degrees, resulting in almost no difference in visible light transmittance between the presence and absence of water on the surface. Therefore, the polishing pads containing the light-transmitting components of Examples 1-1 to 1-2 do not exhibit uneven visible light transmittance between the presence and absence of slurry on the surface, enabling more accurate determination of the polishing endpoint.

[0623] <Manufacturing Example 1-1>

[0624] An additional 60 parts by mass of DMF and 5 parts by mass of water are added to 100 parts by mass of a solution containing 30 parts by mass of polyester polyurethane resin and 70 parts by mass of DMF with a modulus of 7.8 MPa and the mixture is then stirred to obtain a resin-containing solution.

[0625] The obtained resin-containing solution was filtered to remove insoluble components. The solution was then cast onto a polyester film using a doctor blade coater to a thickness of 0.8 mm. The polyester film with the cast resin-containing solution was then immersed in a coagulation bath (water as the coagulating solution) to allow the resin-containing solution to solidify. The polyester film was then peeled off, cleaned, and dried to obtain a polyurethane resin film with multiple interconnected teardrop-shaped air bubbles. The surface of the obtained polyurethane resin film was then wheel-treated to a thickness of 0.73 mm. A 0.188 μm thick PET resin substrate was then bonded to the opposite side of the wheel-treated surface using an adhesive. Embossing was then performed on the surface of the polyurethane resin film, creating a grid pattern of rectangular grooves with a groove width of 1 mm, a groove spacing of 4 mm, and a groove depth of 0.45 mm. Using a circular punching die with a diameter of 18 mm, three holes are equally spaced on a concentric circle located at half the radius of the polishing pad, at a distance from the center of the polishing pad on the side with the grooved surface, thus creating the first through hole. Double-sided tape with release paper on one side is adhered to the side of the resin substrate that is not bonded with the polyurethane resin film. A circular punching die with a diameter of 9 mm is inserted into the first through hole with a diameter of 18 mm to create a second through hole, penetrating the double-sided tape and release paper. The holes are then created so that the centers of the first and second through holes are approximately the same. As a light-transmitting component, a single-sided plasma-treated acrylic resin film (manufactured by Mitsubishi Chemical Corporation, ACRYPLEN HBS006, thickness 150 μm) is prepared. Three pieces are cut with a diameter of 17 mm. The double-sided tape, protruding in a ring shape within the first through hole, is adhered to the light-transmitting component with the surface-treated side of the light-transmitting component as the polishing surface, thus creating the polishing pad.

[0626] <Manufacturing Examples 1-2>

[0627] An additional 60 parts by mass of DMF and 5 parts by mass of water are added to 100 parts by mass of a solution containing 30 parts by mass of polyester polyurethane resin and 70 parts by mass of DMF with a modulus of 7.8 MPa and the mixture is then stirred to obtain a resin-containing solution.

[0628] The obtained resin-containing solution was filtered to remove insoluble components. The solution was then cast onto a polyester film using a doctor blade coater to a thickness of 0.8 mm. The polyester film with the cast resin-containing solution was then immersed in a coagulation bath (water as the coagulating solution) to allow the resin-containing solution to solidify. The polyester film was then peeled off, cleaned, and dried to obtain a polyurethane resin film with multiple interconnected teardrop-shaped air bubbles. The surface of the obtained polyurethane resin film was then wheel-treated to a thickness of 0.73 mm. A 0.188 μm thick PET resin substrate was then bonded to the opposite side of the wheel-treated surface using an adhesive. Embossing was then performed on the surface of the polyurethane resin film, creating a grid pattern of rectangular grooves with a groove width of 1 mm, a groove spacing of 4 mm, and a groove depth of 0.45 mm. A double-sided adhesive tape with a thickness of approximately 0.1 mm and release paper on one side is bonded to the unbonded polyurethane resin film side of the resin substrate (PET substrate thickness 0.023 mm, adhesive component thickness in both the surface and back of the PET substrate 0.04 mm). Using a 20 mm diameter circular punch, three holes are equally spaced on a concentric circle located at half the radius of the polishing pad, at a distance from the center of the polishing pad on the grooved side, thus creating the first through-hole. The release paper is peeled off from the double-sided adhesive tape. An acrylic resin film (manufactured by Mitsubishi Chemical Corporation, ACRYPLEN HBS006, thickness 150 μm), with the same diameter as the polishing layer and treated on one side, is prepared as a light-transmitting component. The adhesive portion of the double-sided adhesive tape is then bonded to the surface-treated side of the light-transmitting component. As another layer, a double-sided adhesive tape with a thickness of about 0.1 mm and release paper on one side is prepared (the thickness of the PET substrate is 0.023 mm, and the thickness of the adhesive component in the surface and back of the PET substrate is 0.04 mm). Three holes are made at the position where they overlap with the first through hole when viewed along the thickness direction, thereby setting the second through hole, so that it is bonded to the untreated side of the light-transmitting component, thereby manufacturing an abrasive pad.

[0629] <Manufacturing Examples 1-3>

[0630] An additional 60 parts by mass of DMF and 5 parts by mass of water are added to 100 parts by mass of a solution containing 30 parts by mass of polyester polyurethane resin and 70 parts by mass of DMF with a modulus of 7.8 MPa and the mixture is then stirred to obtain a resin-containing solution.

[0631] The obtained resin-containing solution was filtered to remove insoluble components. The solution was then cast onto a polyester film using a doctor blade coater to a thickness of 0.8 mm. The polyester film with the cast resin-containing solution was then immersed in a coagulation bath (water as the coagulating solution) to allow the resin-containing solution to solidify. The polyester film was then peeled off, cleaned, and dried to obtain a polyurethane resin film with multiple interconnected teardrop-shaped air bubbles. The surface of the obtained polyurethane resin film was then wheel-treated to a thickness of 0.73 mm. A 0.188 μm thick PET resin substrate was then bonded to the opposite side of the wheel-treated surface using an adhesive. Embossing was then performed on the surface of the polyurethane resin film, creating a grid pattern of rectangular grooves with a width of 1 mm, a spacing of 4 mm, and a depth of 0.45 mm. Other layers were then bonded to the unbonded polyurethane resin film side of the resin substrate using a hot-melt adhesive. As other layers, a nonwoven fabric with a thickness of 0.50 mm and a density of 0.35 g / cm³ is used, made from polyester fibers with a fineness of 2 dtex and a fiber length of 51 mm via needle punching. 3 Double-sided tape with release paper on one side is bonded to the non-woven fabric surface where the polyurethane resin film is not adhered. Using a 20mm diameter circular punch, three holes are equally spaced on concentric circles located at half the radius of the polishing pad, from the center of the polishing pad on the grooved surface, thus creating a first and second through-hole. Three single-sided plasma-treated acrylic / polycarbonate resin sheets (manufactured by Sumitomo Chemical Co., Ltd., TECHNOLLYC001, 500μm thickness) are cut as light-transmitting components, each 20mm in diameter. Hot-melt adhesive is applied to the side of the circular light-transmitting component, and the surface-treated side of the light-transmitting component is bonded to the side within the second through-hole, thus manufacturing the polishing pad.

[0632] The light transmittance of the grinding pads in Examples 1-1 to 1-3 did not change significantly with or without the presence of water-based slurry, thus enabling high-precision detection of the grinding endpoint.

[0633] <<Second Method of Grinding Pad>>

[0634] [Example 2-1]

[0635] A coating solution was prepared by diluting 90 parts by weight of dipentaerythritol hexaacrylate (DPHA) (manufactured by Shin-Nakamura Chemical Industry Co., Ltd., NK ester A-DPH), 25 parts by weight of an acrylate polymer with ion-binding hydrophilic groups (including ammonium cations) (ACRIT 8WX-030 (40% solution) manufactured by Taisei Finechemical Co., Ltd.) (i.e., 8WX-030, with a total solid content of 10% by weight relative to DPHA and 8WX-030), and 3 parts by weight of 1-hydroxycyclohexylphenyl ketone (manufactured by IGM Resin BV, IRGACURE 184) with propylene glycol monomethyl ether to a non-volatile fraction of 30% (※10% 8WX added). The obtained coating solution was applied to an acrylic resin sheet (manufactured by Mitsubishi Chemical Co., Ltd., ACRYPLEN HBS006, 150 μm thick) using a bar coater and pre-dried at 80°C for 1 minute. Next, a 5 μm thick coating was formed on an acrylic resin sheet by ultraviolet irradiation with a high-pressure mercury lamp in air. The resulting acrylic resin sheet with the coating was used as the endpoint detection window.

[0636] [Comparative Example 2-1]

[0637] A commercially available acrylic resin sheet (manufactured by Mitsubishi Chemical Corporation, ACRYPLEN HBS006, 150 μm thick) was used as the endpoint detection window.

[0638] [Example 2-2]

[0639] The composition was changed to 50 parts by weight of DPHA and 125 parts by weight of 8WX-030 (i.e., 8WX-030 with a total solid content of DPHA and 8WX-030 of 50% by weight). Otherwise, an acrylic resin sheet with a coating was prepared in the same manner as in Example 2-1 and used as an endpoint detection window.

[0640] [Examples 2-3]

[0641] The composition was changed to 30 parts by weight of DPHA and 175 parts by weight of 8WX-030 (i.e., 70% by weight of 8WX-030 relative to the total solid content of DPHA and 8WX-030). Otherwise, an acrylic resin sheet with a coating was prepared in the same manner as in Example 2-1 and used as an endpoint detection window.

[0642] [Examples 2-4]

[0643] The composition was changed to 100 parts by weight of DPHA and 0 parts by weight of 8WX-030 (i.e., 8WX-030 with a total solid content of DPHA and 8WX-030 of 0% by weight). Otherwise, an acrylic resin sheet with a coating was prepared in the same manner as in Example 2-1 and used as an endpoint detection window.

[0644] <Water Contact Angle Measurement>

[0645] Using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd., DropMaster500), 1 drop (2 μL) of water was added from the injection needle, and the contact angle was measured after 3 seconds.

[0646] The water contact angle of the surface was determined using the method described above. A water contact angle of less than 20 degrees was rated as ◎, greater than 20 degrees but less than 50 degrees was rated as 〇, greater than 50 degrees but less than 80 degrees was rated as △, and greater than 80 degrees was rated as ×. The results are shown in Table 2.

[0647] <Light transmittance measurement>

[0648] The visible light transmittance of the light-transmitting components of Examples 2-1 to 2-4 and Comparative Example 2-1 was measured using a UV-Vis-NIR spectrophotometer V-770 (manufactured by Nippon Spectrophotometer Co., Ltd.) by the following method.

[0649] 1. Measurement under conditions of adhering water

[0650] (1) Place it in a quartz glass trough and measure the blank group.

[0651] (2) Cut the light-transmitting components of Examples 2-1 to 2-4 and Comparative Example 2-1 into sizes of 9mm × 50mm.

[0652] (3) Place the translucent component on a paper towel (KIMTOWEL, manufactured by Nippon Paper CRECIA Co., Ltd.), and spray purified water three times from a distance of 20 cm onto the surface of the translucent component (Examples 2-1 to 2-4 are surfaces only coated, Comparative Example 2-1 is only one surface) using a spray method (50 mL capacity, PP bottle). The amount of water sprayed each time is 0.160 to 0.165 mL, and the amount of water adhering to the surface of the translucent component is 0.01 to 0.03 mL. After spraying, let the translucent component stand vertically for 60 seconds. Place the translucent component in the quartz glass tank with the unsprayed, water-covered surface in contact with the inner surface of the quartz glass tank.

[0653] (3) The light-transmitting component is arranged on the inner wall of the quartz glass tank with the coated surface of the light-transmitting component facing away from the light source, so that the entire surface of the light-transmitting component is in contact with the light source side of the quartz tank.

[0654] (4) The linear transmittance of light relative to 250–1000 nm was measured using a UV-Vis-NIR spectrophotometer V-770 (manufactured by Nippon Spectrophotometer Co., Ltd.).

[0655] (5) Based on JIS A5759:2008, the visible light transmittance relative to wavelengths of 380–780 nm was calculated.

[0656] 2. Measurement without adhering water

[0657] (1) Place it in a quartz glass trough and measure the blank group.

[0658] (2) Cut the light-transmitting components of Examples 2-1 to 2-4 and Comparative Example 2-1 into sizes of 9mm × 50mm.

[0659] (3) The light-transmitting component is arranged on the inner wall of the quartz glass tank with the coated surface of the light-transmitting component facing away from the light source, so that the entire surface of the light-transmitting component is in contact with the light source side of the quartz tank.

[0660] (4) The linear transmittance of light relative to 250–1000 nm was measured using a UV-Vis-NIR spectrophotometer V-770 (manufactured by Nippon Spectrophotometer Co., Ltd.).

[0661] (5) Based on JIS A5759:2008, the visible light transmittance relative to wavelengths of 380–780 nm was calculated.

[0662] Using the above method, for the light-transmitting components of Examples 2-1 to 2-4 and Comparative Example 2-1, the difference between the visible light transmittance when the surface is covered with water and when it is not covered with water (visible light transmittance without water - visible light transmittance with water) was calculated. A difference of 5% or less was rated as ◎, greater than 5% but less than 10% was rated as 0, greater than 10% but less than 15% was rated as △, and greater than 15% was rated as ×. The results are shown in Table 2.

[0663] [Table 2]

[0664]

[0665] The results of the tests showed that in Comparative Example 2-1, where the surface of the grinding side was uncoated, there was a significant difference in visible light transmittance between the presence and absence of water on the surface. In contrast, in Examples 2-1 to 2-4, where the surface of the grinding side was coated with a hydrophilic resin, the difference in light transmittance between the presence and absence of water was reduced compared to Comparative Example 2-1. Furthermore, in the light-transmitting components of Examples 2-1 to 2-3, since the surface of the grinding side was coated with a resin having ion-binding hydrophilic groups, there was almost no difference in visible light transmittance between the presence and absence of water on the surface. Therefore, the grinding pads containing the light-transmitting components of Examples 2-1 to 2-4, especially Examples 2-1 to 2-3, did not exhibit uneven visible light transmittance between the presence and absence of slurry on the surface, allowing for more accurate determination of the grinding endpoint.

[0666] <Manufacturing Example 2-1>

[0667] An additional 60 parts by mass of DMF and 5 parts by mass of water are added to 100 parts by mass of a solution containing 30 parts by mass of polyester polyurethane resin and 70 parts by mass of DMF with a modulus of 7.8 MPa and the mixture is then stirred to obtain a resin-containing solution.

[0668] The obtained resin-containing solution was filtered to remove insoluble components. The solution was then cast onto a polyester film using a doctor blade coater to a thickness of 0.8 mm. The polyester film with the cast resin-containing solution was then immersed in a coagulation bath (water as the coagulating solution) to allow the resin-containing solution to solidify. The polyester film was then peeled off, cleaned, and dried to obtain a polyurethane resin film with multiple interconnected teardrop-shaped air bubbles. The surface of the obtained polyurethane resin film was then wheel-treated to a thickness of 0.73 mm. A 0.188 μm thick PET resin substrate was then bonded to the opposite side of the wheel-treated surface using an adhesive. Embossing was then performed on the surface of the polyurethane resin film, creating a grid pattern of rectangular grooves with a groove width of 1 mm, a groove spacing of 4 mm, and a groove depth of 0.45 mm. Using a circular punching die with a diameter of 18 mm, three holes are equally spaced on a concentric circle located at half the radius of the grinding pad, at a distance from the center of the grinding pad on the side of the groove being treated, thus creating a first through hole. Double-sided tape with release paper on one side is adhered to the side of the resin substrate that is not covered with the polyurethane resin film. A circular punching die with a diameter of 9 mm is inserted into the first through hole with a diameter of 18 mm to create a second through hole, penetrating the double-sided tape and release paper. The holes are then created so that the centers of the first and second through holes are approximately the same. As a light-transmitting component, an acrylic resin sheet with a coating as described in Example 2-1 is prepared. Three sheets with a diameter of 17 mm are cut. The double-sided tape, protruding in a ring shape within the first through hole, is adhered to the light-transmitting component with the coated side of the light-transmitting component as the grinding surface side, thus creating a grinding pad.

[0669] <Manufacturing Example 2-2>

[0670] An additional 60 parts by mass of DMF and 5 parts by mass of water are added to 100 parts by mass of a solution containing 30 parts by mass of polyester polyurethane resin and 70 parts by mass of DMF with a modulus of 7.8 MPa and the mixture is then stirred to obtain a resin-containing solution.

[0671] The obtained resin-containing solution was filtered to remove insoluble components. The solution was then cast onto a polyester film using a doctor blade coater to a thickness of 0.8 mm. The polyester film with the cast resin-containing solution was then immersed in a coagulation bath (water as the coagulating solution) to allow the resin-containing solution to solidify. The polyester film was then peeled off, cleaned, and dried to obtain a polyurethane resin film with multiple interconnected teardrop-shaped air bubbles. The surface of the obtained polyurethane resin film was then wheel-treated to a thickness of 0.73 mm. A 0.188 μm thick PET resin substrate was then bonded to the opposite side of the wheel-treated surface using an adhesive. Embossing was then performed on the surface of the polyurethane resin film, creating a grid pattern of rectangular grooves with a groove width of 1 mm, a groove spacing of 4 mm, and a groove depth of 0.45 mm. A double-sided adhesive tape with a thickness of approximately 0.1 mm and release paper on one side is bonded to the unbonded polyurethane resin film side of the resin substrate (PET substrate thickness 0.023 mm, adhesive component thickness in both the surface and back of the PET substrate 0.04 mm). Using a 20 mm diameter circular punch, three holes are equally spaced on concentric circles at a distance of 1 / 2 the radius of the abrasive pad from the center of the abrasive pad on the grooved side, thus creating the first through-hole. The release paper from the double-sided adhesive tape is peeled off. As a light-transmitting component, an acrylic resin sheet with a coated film, as described in Example 2-1, is prepared, and the adhesive portion of the double-sided adhesive tape is bonded to the coated side of the light-transmitting component. As another layer, a double-sided adhesive tape with a thickness of about 0.1 mm and release paper on one side is prepared (the thickness of the PET substrate is 0.023 mm, and the thickness of the adhesive component in the surface and back of the PET substrate is 0.04 mm). Three holes are made at the position where they overlap with the first through hole when viewed along the thickness direction, thereby creating a second through hole, so that it is bonded to the uncoated side of the acrylic resin film light-transmitting component, thereby manufacturing an abrasive pad.

[0672] <Manufacturing Example 2-3>

[0673] An additional 60 parts by mass of DMF and 5 parts by mass of water are added to 100 parts by mass of a solution containing 30 parts by mass of polyester polyurethane resin and 70 parts by mass of DMF with a modulus of 7.8 MPa and the mixture is then stirred to obtain a resin-containing solution.

[0674] The obtained resin-containing solution was filtered to remove insoluble components. The solution was then cast onto a polyester film using a doctor blade coater to a thickness of 0.8 mm. The polyester film with the cast resin-containing solution was then immersed in a coagulation bath (water as the coagulating solution) to allow the resin-containing solution to solidify. The polyester film was then peeled off, cleaned, and dried to obtain a polyurethane resin film with multiple interconnected teardrop-shaped air bubbles. The surface of the obtained polyurethane resin film was then wheel-treated to a thickness of 0.73 mm. A 0.188 μm thick PET resin substrate was then bonded to the opposite side of the wheel-treated surface using an adhesive. Embossing was then performed on the surface of the polyurethane resin film, creating a grid pattern of rectangular grooves with a width of 1 mm, a spacing of 4 mm, and a depth of 0.45 mm. Other layers were then bonded to the unbonded polyurethane resin film side of the resin substrate using a hot-melt adhesive. As other layers, a nonwoven fabric with a thickness of 0.50 mm and a density of 0.35 g / cm³ is used, made from polyester fibers with a fineness of 2 dtex and a fiber length of 51 mm via needle punching. 3 Double-sided tape with release paper on one side is adhered to the non-woven fabric surface where the polyurethane resin film is not bonded. Using a circular punch die with a diameter of 20 mm, three holes are equally spaced on a concentric circle located at half the radius of the grinding pad, at a distance from the center of the grinding pad on the grooved surface, thus creating a first through hole and a second through hole. Three acrylic resin sheets with a coating from Example 2-1 are cut with a diameter of 20 mm as light-transmitting components. Hot-melt adhesive is applied to the side of the circular light-transmitting component, and the coated side of the light-transmitting component is adhered to the side of the second through hole, with the coated side becoming the grinding surface, thereby manufacturing the grinding pad.

[0675] The light transmittance of the abrasive pads in Examples 2-1 to 2-3 did not change significantly with or without the presence of water-based slurry, thus enabling high-precision detection of the abrasive endpoint.

[0676] <<Third-Party Abrasive Pads>>

[0677] <Example 3-1>

[0678] An acrylic resin sheet (manufactured by Mitsubishi Chemical Corporation, ACRYPLENHBS006) with dimensions of 20 mm in length, 20 mm in width, and 0.15 mm in thickness was subjected to plasma treatment under the conditions of argon flow rate of 10 sccs, reaction time of 2 minutes, and pressure of 50 Pa. Next, it was immersed in a 40 mol% aqueous solution of acrylic acid, and a graft polymerization reaction was carried out at 80°C for 1 hour while bubbling with nitrogen. Following this, it was ultrasonically cleaned in distilled water for 2 hours and vacuum dried at 80°C for 6 hours. The resulting translucent resin component was used as the translucent resin component of Example 3-1.

[0679] <Example 3-2>

[0680] An acrylic resin sheet (manufactured by Mitsubishi Chemical Corporation, ACRYPLENHBS006) with dimensions of 20 mm in length, 20 mm in width, and 0.15 mm in thickness was subjected to plasma polymerization at an argon flow rate of 10 sccs, a reaction time of 2 minutes, and a pressure of 50 Pa. Next, it was immersed in a 40 mol% aqueous solution of acrylic acid and subjected to graft polymerization at 80°C for 1 hour while being bubbled with nitrogen. Afterward, it was ultrasonically cleaned in distilled water for 2 hours and vacuum dried at 80°C for 6 hours. The grafted acrylic resin sheet was then subjected to a polymer complex formation reaction in 25 ml of a 5% (w / w) aqueous solution of polyvinylbenzyltrimethylammonium chloride (molecular weight 43000) while stirring for 30 minutes. The membrane was then washed with water and dried to form a polymer composite. The resulting translucent resin component was used as the translucent resin component in Example 3-2.

[0681] <Comparative Example 3-1>

[0682] An acrylic resin sheet (manufactured by Mitsubishi Chemical Co., Ltd., ACRYPLENHBA001P ACRYPLEN HBS006) with a length of 20 mm, width of 20 mm, and thickness of 0.15 mm was used as the light-transmitting resin component of Comparative Example 3-1.

[0683] <Comparative Example 3-2>

[0684] An acrylic resin sheet (manufactured by Mitsubishi Chemical Corporation, ACRYPLENHBA001P ACRYPLEN HBS007) with a length of 20 mm, width of 20 mm, and thickness of 0.15 mm was subjected to plasma treatment under the conditions of argon flow rate of 10 sccs, reaction time of 2 minutes, and pressure of 50 Pa. The resulting translucent resin component was used as the translucent resin component of Comparative Example 3-2.

[0685] <Contact Angle Maintenance Evaluation>

[0686] To evaluate the change in hydrophilicity over time, the water contact angles of the translucent resin components of Examples 3-1 to 3-2 and Comparative Examples 3-1 to 3-2 were measured after 2 days and 2 weeks. The water contact angles were measured using an automatic contact angle meter, DropMaster DM500 (manufactured by Kyowa Interface Science Co., Ltd.), by the following method.

[0687] (1) Fill the syringe with distilled water and install the dispensing device, set it to DM500.

[0688] (2) Cut the test sample into 5mm×50mm size and attach it to the stage.

[0689] (3) Start the analysis software, select the contact angle measurement [droplet method], and set the parameters.

[0690] Waiting time before measurement: 1000ms

[0691] Measurement time interval: 1000ms

[0692] Number of consecutive measurements: 180

[0693] (4) Set the measured droplet volume, the position of the injection needle on the image monitor, and optimize the focus value of the image monitor.

[0694] (5) Drop the liquid onto the sample, start the measurement, and read the water contact angle 10 seconds after the start of the measurement.

[0695] The results of the water contact angle measurement test are shown in Table 3.

[0696] The results of the measurements show that cases where the contact angle is below 80 degrees (°) after 2 days and 2 weeks are rated as 0, and cases other than this are rated as ×.

[0697] <Evaluation of Residues on Windows>

[0698] The abrasive pad was manufactured using the light-transmitting resin components of Examples 3-1 to 3-2 and Comparative Examples 3-1 to 3-2 as follows.

[0699] An additional 60 parts by mass of DMF and 5 parts by mass of water are added to 100 parts by mass of a solution containing 30 parts by mass of polyester-based polyurethane resin and 70 parts by mass of DMF (100% modulus 7.8 MPa) and mixed to obtain a resin-containing solution. The obtained resin-containing solution is filtered to remove insoluble components. The above solution is cast onto a polyester sheet using a doctor blade coater to a coating thickness of 0.8 mm. The polyester sheet with the cast resin-containing solution is then immersed in a coagulation bath (coagulation solution is water) to allow the resin-containing solution to solidify. After the resin-containing solution solidifies, the polyester sheet is peeled off, washed, and dried to obtain a polyurethane resin sheet. The surface of the obtained polyurethane resin sheet is treated with a grinding wheel to a thickness of 0.73 mm. Then, a 0.188 mm thick PET resin substrate is bonded to the opposite side of the grinding wheel-treated surface using an adhesive. Embossing is then performed on the surface of the polyurethane resin sheet, creating a grid pattern of grooves with a cross-section of 1 mm width, 4 mm spacing, and 0.45 mm depth. The grooved polyurethane resin sheet is then punched into a circle with a diameter of 740 mm using a punching die. Using an 18 mm diameter circular punching die, three holes are independently and evenly spaced on concentric circles extending from the center of the circular polyurethane resin sheet to a point half the radius on the grooved side, thus creating the first through hole. A circular double-sided tape with a thickness of approximately 0.1 mm and a diameter of 790 mm, having a release paper on one side, is bonded as a second layer to the unbonded polyurethane resin sheet of the aforementioned resin substrate. The tape (PET substrate thickness 0.023 mm, adhesive component thickness on both the surface and back of the PET substrate 0.04 mm) is cut to the same diameter as the polyurethane resin sheet. Next, a circular punch with a diameter of 9 mm is inserted into a first through-hole with a diameter of 18 mm to create a second through-hole that passes through the double-sided tape and the release paper. The holes are then made so that the center of the first through-hole is approximately the same as the center of the second through-hole. Three pieces of the transparent resin component prepared in Examples 3-1, 3-2, Comparative Examples 3-1, and 3-2 are each cut to a diameter of 17 mm, and the double-sided tape protruding in a ring shape within the first through-hole is bonded to the transparent resin component to create an abrasive pad.

[0700] Next, as the object of polishing, a patterned substrate with tungsten (W) lines and TEOS (silicon oxide film) gaps was prepared. 500 substrates were polished using each polishing pad under the following conditions. Then, the cross-section of the transparent resin component was observed using an energy-dispersive X-ray spectrometer (EDS) to evaluate whether there were any residues adhering to the polished surface side of the transparent resin component.

[0701] Grinding machine used: EBARA F-REX300

[0702] Grinding pressure: 2.5 psi

[0703] Grinding pad: Grinding pad: Manufactured by FUJIBO Ehime Co., Ltd. H600

[0704] Abrasive: Manufactured by Planar, model "BSL8176C"

[0705] Diamond dressing tool: A188, manufactured by 3M.

[0706] Pad break-in: 30 N x 30 minutes, diamond dresser 54 rpm, platform speed 80 rpm, ultrapure water 200 mL / min

[0707] Adjustments: Ex-situ (extra-situ repair), 30N, 4 scans, 16 seconds

[0708] Grinding: Platform speed 70 rpm, die head speed 71 rpm, slurry flow rate 200 mL / min

[0709] Grinding time: Approximately 60 seconds

[0710] The results are shown in Table 3.

[0711] [Table 3]

[0712]

[0713] The results of the above tests showed that in Comparative Example 3-1 without surface treatment, the water contact angle was as high as approximately 87 degrees after 2 days and 2 weeks, indicating poor wettability. The results of the window residue evaluation using EDS showed that if polishing was performed using a polishing pad with the light-transmitting resin component of Comparative Example 3-1, a large amount of Si elements were visible on the surface of the light-transmitting resin component. This can be considered as Si being retained and fixed on the highly hydrophobic window surface.

[0714] In Comparative Example 3-2, which only underwent plasma treatment, although the contact angle was smaller than that of the untreated product after 2 days, it became the same as that of the untreated product after 2 weeks, thus losing the surface modification effect of plasma treatment. Furthermore, in EDS measurements, Si elements were detected on the surface of the translucent resin component, suggesting that Si accumulated on the window surface where hydrophilicity was insufficient.

[0715] On the other hand, Example 3-1, which underwent graft polymerization treatment, maintained a low contact angle even after 2 weeks. Compared to Example 3-1, Example 3-2, which was grafted polymer composited, showed a further reduction in contact angle, which was also maintained after 2 weeks. Furthermore, in either Example 3-1 or 3-2, Si was not detected in EDS measurements.

[0716] Based on the above results, it can be seen that the abrasive pad containing the light-transmitting resin components of Examples 3-1 to 3-2 can reduce the adhesion and fixation of abrasive debris to the surface of the light-transmitting resin component (window component), and can perform stable light detection.

[0717] <<Fourth Type of Abrasive Pad>>

[0718] <Example 4-1>

[0719] 50 parts by weight of aliphatic urethane acrylate ("EBECRYL 2000" manufactured by DAICEL-ALLNEX) and 50 parts by weight of polyethylene glycol diacrylate ("EBECRYL 11" manufactured by DAICEL-ALLNEX, with a mass-average molecular weight of 700 and 13 ethylene oxide units per monomer) were mixed, and 5 parts by weight of photopolymerization initiator ("IRGACURE 184" manufactured by BASF) were further added. The mixture was stirred evenly using a mixing device to obtain a resin composition. The obtained resin composition was evenly coated onto one side of an acrylic resin sheet ("CLAREX S" manufactured by Nitto Resin Kogyo Co., Ltd., 400 μm thick) using a rod coater. The sheet was then dried in an oven maintained at 50°C for 10 minutes. After drying, the sheet was irradiated with ultraviolet light using an 80 W / cm metal halide lamp with a cumulative irradiation dose of 900 mJ / cm. 2 Ultraviolet light was used to cure the resin composition, forming a surface layer with a thickness of 3.5 μm. The resulting acrylic resin sheet with the surface layer was used as the endpoint detection window.

[0720] <Example 4-2>

[0721] Using a mixing and stirring device, 58 parts by weight of polyethylene glycol diacrylate ("A-1000" manufactured by Shin-Nakamura Chemical Industry Co., Ltd., with a mass-average molecular weight of 1140 and 23 ethylene oxide units per monomer) and 39 parts by weight of C 2-3 Alkoxylated pentaerythritol tetraacrylate ("EBECRYL 40" manufactured by DAICEL-ALLNEX Co., Ltd., with a mass-average molecular weight of 571 and ethylene oxide / propylene oxide units per monomer of 4), 3 parts by weight of photopolymerization initiator ("IRGACURE 184" manufactured by BASF), and 100 parts by weight of propylene glycol monomethyl ether as a solvent were uniformly mixed to obtain a resin composition. The obtained resin composition was coated onto an acrylic resin sheet in the same manner as in Example 4-1 to form a surface layer for use as an endpoint detection window.

[0722] <Example 4-3>

[0723] Using a mixing and stirring device, 67 parts by weight of ethoxylated glycerol triacrylate ("A-GLY-20E" manufactured by Shin-Nakamura Chemical Industry Co., Ltd., with a mass-average molecular weight of 1134 and 20 ethylene oxide units per monomer) and 28 parts by weight of C 2-3 Alkoxylated pentaerythritol tetraacrylate ("EBECRYL 40" manufactured by DAICEL-ALLNEX Co., Ltd., with a mass-average molecular weight of 571 and ethylene oxide / propylene oxide units per monomer of 4), 5 parts by weight of photopolymerization initiator ("IRGACURE 184" manufactured by BASF), and 100 parts by weight of propylene glycol monomethyl ether as a solvent were uniformly mixed to obtain a resin composition. The obtained resin composition was coated onto an acrylic resin sheet in the same manner as in Example 4-1 to form a surface layer for use as an endpoint detection window.

[0724] <Comparative Example 4-1>

[0725] A commercially available acrylic resin sheet (manufactured by Nitto Resin Kogyo Co., Ltd., CLAREX S, 400μm thick) was used as the endpoint detection window.

[0726] <Water Contact Angle Measurement>

[0727] Using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd., DropMaster500), 1 drop (2 μL) of water was added from the injection needle, and the contact angle was measured after 3 seconds.

[0728] The water contact angle of the surface was measured using the method described above. A decrease of more than 40 degrees compared to the water contact angle before the formation of the surface layer was evaluated as ○. The results are shown in Table 4.

[0729] <Light transmittance measurement>

[0730] The visible light transmittance of the transparent resin components of Examples 4-1 to 4-3 and Comparative Example 4-1 was measured using a UV-Vis-NIR spectrophotometer V-770 (manufactured by Nippon Spectroscopy Co., Ltd.) by the following method.

[0731] 1. Measurement under conditions of adhering water

[0732] (1) Place it in a quartz glass trough and measure the blank group.

[0733] (2) Cut the light-transmitting resin components of Examples 4-1 to 4-3 and Comparative Example 4-1 into sizes of 9mm × 50mm.

[0734] (3) Place the translucent resin component on a paper towel (KIMTOWEL, manufactured by Nippon Paper CRECIA Co., Ltd.), and spray purified water three times from a distance of 20 cm onto the surface of the translucent resin component (Examples 4-1 to 4-3 are surfaces only coated, Comparative Example 4-1 is only one surface) using a spray method (50 mL capacity, PP bottle). The amount of water sprayed each time is 0.160 to 0.165 mL, and the amount of water adhering to the surface of the translucent resin component is 0.01 to 0.03 mL. After spraying, let the translucent resin component stand vertically for 60 seconds. Place the translucent resin component in the quartz glass tank with the unsprayed, water-covered surface in contact with the inner surface of the quartz glass tank.

[0735] (3) The light-transmitting resin component is arranged on the inner wall of the quartz glass tank with the coated surface facing away from the light source.

[0736] (4) The linear transmittance of light relative to 250–1000 nm was measured using a UV-Vis-NIR spectrophotometer V-770 (manufactured by Nippon Spectrophotometer Co., Ltd.).

[0737] (5) Based on JIS A5759:2008, the visible light transmittance relative to wavelengths of 380–780 nm was calculated.

[0738] 2. Measurement without water adhering to it

[0739] (1) Place it in a quartz glass trough and measure the blank group.

[0740] (2) Cut the light-transmitting resin components of Examples 4-1 to 4-3 and Comparative Example 4-1 into sizes of 9mm × 50mm.

[0741] (3) The light-transmitting resin component is arranged on the inner wall of the quartz glass tank with the coated surface facing away from the light source.

[0742] (4) The linear transmittance of light relative to 250–1000 nm was measured using a UV-Vis-NIR spectrophotometer V-770 (manufactured by Nippon Spectrophotometer Co., Ltd.).

[0743] (5) Based on JIS A5759:2008, the visible light transmittance relative to wavelengths of 380–780 nm was calculated.

[0744] Using the above methods, for the light-transmitting resin components of Examples 4-1 to 4-3 and Comparative Example 4-1, the difference between the visible light transmittance when water is attached to the surface and the visible light transmittance when water is not attached (visible light transmittance without water - visible light transmittance with water) was calculated. A difference in light transmittance of less than 10% was evaluated as ○, and a difference of more than 10% was evaluated as ×. The results are shown in Table 4.

[0745] <Reagent Resistance Evaluation>

[0746] Samples from Examples 4-1 to 4-3, each measuring 15mm × 15mm, were immersed in acidic / alkaline pulp at 40°C for 24 hours. After immersion, the samples were removed and the surface moisture was wiped off with a paper towel (KIMTOWEL, manufactured by Nippon Paper CRECIA Co., Ltd.). The condition of the surface layer was observed. Any peeling or deformation not visually detectable was rated as 0. The following pulps were used as the acidic and alkaline pulps, respectively. The results are shown in Table 4.

[0747] Acidic slurry: Potassium permanganate slurry (FUJIMI: DSC-201), pH 2;

[0748] Alkaline slurry: Colloidal silica slurry (slurry manufactured by Cabot: SS25, with added KOH), pH 11.

[0749] [Table 4]

[0750]

[0751] The results of the tests showed that in Comparative Example 4-1, which did not have a surface layer of resin containing constituent units from polyfunctional (meth)acrylate monomers on the grinding surface side, there was a significant difference in visible light transmittance between the presence and absence of water on the surface. In contrast, in Examples 4-1 to 4-3, which had a surface layer of the resin on the grinding surface side, the difference in visible light transmittance between the presence and absence of water on the surface was reduced compared to Comparative Example 4-1, and there was almost no difference in visible light transmittance between the presence and absence of water on the surface. Therefore, the grinding pads containing the light-transmitting resin components of Examples 4-1 to 4-3 did not exhibit uneven visible light transmittance between the presence and absence of slurry on the surface, enabling more accurate determination of the grinding endpoint.

[0752] <Manufacturing Example 4-1>

[0753] An additional 60 parts by mass of DMF and 5 parts by mass of water are added to 100 parts by mass of a solution containing 30 parts by mass of polyester-based polyurethane resin and 70 parts by mass of DMF (100% modulus 7.8 MPa) and mixed to obtain a resin-containing solution. The obtained resin-containing solution is filtered to remove insoluble components. The above solution is cast onto a polyester film using a doctor blade coater to a coating thickness of 0.81 mm. Then, the polyester film with the cast resin-containing solution is immersed in a coagulation bath (coagulation solution is water) to solidify the resin-containing solution. After that, the polyester film is peeled off, washed, and dried to obtain a polyurethane resin film with multiple teardrop-shaped air bubbles inside, which are interconnected. The surface of the obtained polyurethane resin film is treated with a grinding wheel to a thickness of 0.73 mm. A 0.188 mm thick PET resin substrate is then bonded to the opposite side of the treated surface using an adhesive. Embossing is then performed on the surface of the polyurethane resin film, creating a grid pattern of rectangular grooves with a groove width of 1 mm, a groove spacing of 4 mm, and a groove depth of 0.45 mm. Using an 18 mm diameter circular punch, three holes are equally spaced on concentric circles located at a position half the radius of the grinding pad, at a distance from the center of the grooved surface, forming the first through-hole. Double-sided adhesive tape with release paper on one side is bonded to the side of the resin substrate not bonded to the polyurethane resin film. A 9 mm diameter circular punch is inserted into the 18 mm diameter first through-hole to create a second through-hole, penetrating both the double-sided adhesive tape and the release paper. The holes are then created with the centers of the first and second through-holes approximately aligned. As a light-transmitting component, an acrylic resin sheet with a surface layer as described in Example 4-1 is prepared. Three sheets are cut with a diameter of 17 mm. The surface-treated side of the light-transmitting component is made into a polishing side. Double-sided adhesive tape exposed in a ring shape in the first through hole is bonded to the light-transmitting component to create a polishing pad.

[0754] <Manufacturing Example 4-2>

[0755] An additional 60 parts by mass of DMF and 5 parts by mass of water are added to 100 parts by mass of a solution containing 30 parts by mass of polyester-based polyurethane resin and 70 parts by mass of DMF (100% modulus 7.8 MPa) and mixed to obtain a resin-containing solution. The obtained resin-containing solution is filtered to remove insoluble components. The above solution is cast onto a polyester film using a doctor blade coater to a coating thickness of 0.81 mm. Then, the polyester film with the cast resin-containing solution is immersed in a coagulation bath (coagulation solution is water) to solidify the resin-containing solution. After that, the polyester film is peeled off, washed, and dried to obtain a polyurethane resin film with multiple teardrop-shaped air bubbles inside, which are interconnected. The surface of the obtained polyurethane resin film is treated with a grinding wheel to a thickness of 0.73 mm. A 0.188 mm thick PET resin substrate is then bonded to the opposite side of the treated surface using an adhesive. Embossing is then performed on the surface of the polyurethane resin film, creating a grid pattern of rectangular grooves with a groove width of 1 mm, a groove spacing of 4 mm, and a groove depth of 0.45 mm. A double-sided adhesive tape with a release paper layer on one side (PET substrate thickness 0.023 mm, adhesive component thickness on both the surface and back of the PET substrate 0.04 mm) is bonded to the side of the resin substrate where the polyurethane resin film is not bonded. Using a 9 mm diameter circular punch, three holes are equally spaced on a concentric circle located at a position half the radius of the grinding pad, from the center of the groove-treated side, thus creating the first through-hole. The release paper from the double-sided tape is peeled off. As a light-transmitting component, an acrylic resin sheet with a surface layer, cut to the same size as the polishing layer in Example 4-1, is prepared, and the adhesive portion of the double-sided tape is adhered to the surface layer side of the acrylic resin sheet. As another layer, a double-sided tape with a thickness of approximately 0.11 mm on one side (PET substrate thickness 0.023 mm, adhesive component thickness in both the surface and back of the PET substrate 0.04 mm) is prepared. Three holes with a diameter of 9 mm are made at the position overlapping with the first through hole when viewed along the thickness direction, thereby creating a second through hole, which is then adhered to the uncoated side of the acrylic resin film light-transmitting component, thereby manufacturing the polishing pad.

[0756] The light transmittance of the abrasive pads in Examples 4-1 to 4-2 did not change significantly with or without the presence of water-based slurry, thus enabling high-precision detection of the abrasive endpoint.

[0757] Industrial availability

[0758] According to a first aspect of the present invention, an abrasive pad capable of suppressing uneven light transmittance can be provided.

[0759] According to a second aspect of the present invention, an abrasive pad capable of suppressing uneven light transmittance can be provided.

[0760] According to a third aspect of the present invention, an abrasive pad capable of reducing the adhesion and fixation of abrasive debris to the abrasive surface of a translucent resin component (window component) can be provided.

[0761] According to a fourth aspect of the present invention, an abrasive pad capable of suppressing uneven light transmittance can be provided.

[0762] Therefore, the abrasive pad of the present invention is extremely useful in industry.

[0763] Symbol Explanation

[0764] 1: Grinding pad

[0765] 2: Grinding layer

[0766] 3: Other layers

[0767] 4: Translucent components or translucent resin components

[0768] 4': The uppermost part of a light-transmitting component or a light-transmitting resin component

[0769] 5: Through hole (first through hole)

[0770] 6: Second through hole

[0771] 7: Exposed area

[0772] 8: Slot

[0773] 8': The bottom of the slot

[0774] 9: Coated portion (second type), grafted surface portion (third type), or surface portion on the polished side of a translucent resin component (fourth type).

Claims

1. An abrasive pad having a light-transmitting component and an abrasive layer, The abrasive layer has an abrasive surface for abrading the workpiece, and the abrasive pad has a through hole extending from the abrasive surface to its opposite surface. The light-transmitting member is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member exists within the through-hole, and The water contact angle of the ground surface side of the light-transmitting component is less than 80 degrees. When the polished surface is designated as the upper surface and its opposite surface as the lower surface, the uppermost part of the light-transmitting member is lower than the polished surface. The surface of the light-transmitting component on the grinding side is subjected to plasma treatment or roller blasting treatment.

2. The abrasive pad according to claim 1, wherein, The water contact angle of the surface of the light-transmitting component opposite to the grinding surface is greater than 80 degrees.

3. The abrasive pad according to claim 1 or 2, wherein, The grinding surface has a groove, and when the grinding surface is set as the upper surface and its opposite surface is set as the lower surface, the uppermost part of the light-transmitting member is located at the same position as or below the lowermost part of the groove.

4. The abrasive pad according to claim 1 or 2, wherein, When the through-holes in the polishing layer are designated as the first through-holes, the polishing pad further includes other layers having second through-holes, the second through-holes having an equivalent circular diameter smaller than the first through-hole. The other layers are located on the side of the polishing layer opposite to the polishing surface. When the polishing pad is viewed from the polishing surface side along the thickness direction, the first through-hole and the second through-hole at least partially overlap. The light-transmitting member is arranged such that, when viewed from the grinding surface side of the grinding pad along the thickness direction of the grinding pad, the light-transmitting member exists within the first through hole.

Images