JP6749755B2 - Polishing holder and method for manufacturing the same - Google Patents

Description

The present invention relates to a polishing holder and a method for manufacturing the same.

Conventionally, materials for semiconductor devices, electronic components, etc., particularly, optical materials such as Si substrate (silicon wafer), GaAs (gallium arsenide) substrate, lens, plane parallel plate, reflection mirror, and thin substrate such as LCD (liquid crystal display) substrate. Since the surface (processed surface) of the substrate (workpiece) is required to have flatness, mechanical polishing (lapping) or chemical mechanical polishing (CMP) using a polishing pad together with a slurry is performed.

In such a polishing process, a holder for holding an object to be polished is used. The holder has, for example, a structure in which a frame member made of fiber-reinforced resin is attached to the resin sheet in order to suppress lateral displacement of the object to be polished. As an example of a holder having such a structure, Patent Document 1 describes a holder including a back pad and a frame portion (frame member).

Japanese Patent No. 5421618

In the conventional polishing holder illustrated in Patent Document 1, the back pad and the frame material are joined via an adhesive component such as a double-sided tape or a hot melt adhesive sheet. However, in CMP, an acidic slurry may be used, and in the polishing process, the adhesive component may deteriorate due to the acidic slurry and frictional heat generated during polishing. As a result, peeling may occur between the back pad and the frame material. Also in lapping, particularly when the object to be polished is a difficult-to-process material such as sapphire, SiC, GaN, and diamond that is difficult to polish, peeling occurs between the back pad and the frame material due to the high polishing pressure. Can occur.

Further, in the step of bonding the frame material and the back pad via the adhesive component, for example, in the case of bonding by hot pressing, the back pad having a soft and cushioning property and the thin and hard frame material are generally used as the adhesive component. It will be bonded through. At this time, the adhesive component shrinks due to its curing, and along with that, the soft back pad also comes into contact with the adhesive component in a compressed and deformed state, and also tends to shrink due to heating at the contact portion with the adhesive component. As a result, the contracted portion of the back pad always has internal stress that tends to return to its original state, which may cause a problem of insufficient adhesion between the adhesive component and the back pad.

Furthermore, as described above, since the conventional polishing holder uses the adhesive component, "interfacial destruction between frame material and adhesive component", "interfacial destruction between adhesive component and back pad", "adhesive component" The cohesive failure of the adhesive layer due to the deterioration of "," and three peeling factors are included. As a result, the possibility of peeling tends to increase as compared with the case where there are less than three peeling factors.

The present invention has been made in view of the problems of the above conventional technique, and an object of the present invention is to provide a polishing holder in which peeling inside is suppressed and a manufacturing method thereof.

The present inventors diligently studied to solve the above problems. As a result, they have found that the above problems can be solved by directly joining the constituent members of the holder, and have completed the present invention.

That is, the present invention is as follows.
[1]
A back pad for holding an object to be polished,
A frame member that is directly bonded to the back pad and surrounds the object to be polished,
A holder for polishing, comprising:
[2]
The polishing holder according to [1], wherein the frame material has a thickness of 500 μm or less.
[3]
The polishing holder according to [1] or [2], wherein the polishing holder has a groove portion having at least an opening formed on a surface of the frame material facing the polishing pad during polishing.
[4]
The polishing holder according to any one of [1] to [3], wherein the frame material contains a photocurable resin.
[5]
The polishing holder according to any one of [1] to [4], wherein the frame material contains at least one resin selected from the group consisting of thiol resins, epoxy resins, and urethane resins.
[6]
The polishing holder according to any one of [1] to [5], wherein the frame material does not contain glass fibers.
[7]
A back pad for holding an object to be polished, and a frame material for surrounding the object to be polished, a method for manufacturing a polishing holder,
A step of directly joining the frame member on the back pad,
A method for manufacturing a polishing holder.
[8]
The frame material is formed of a photocurable resin,
The method for manufacturing a polishing holder according to [7], wherein the forming step includes a step of screen-printing the photocurable resin.
[9]
The frame material is formed by filling a material of the frame material or a precursor thereof into a mold arranged on the back pad, and drying the material or curing the precursor to form [7]. Of manufacturing a holder for polishing.

According to the present invention, it is possible to provide a polishing holder in which peeling inside is suppressed and a manufacturing method thereof.

(A) is a top view which shows an example of the polishing holder which concerns on this embodiment, (b) is a schematic diagram which shows the II cross section in (a). (A) is a top view which shows an example of the aspect which has a groove part in the polishing holder which concerns on this embodiment, (b) is a schematic diagram which shows the II-II cross section in (a). It is a schematic diagram which shows the method of using the polish holder of this embodiment at the time of polish of to-be-polished material. 7 is a schematic cross-sectional view of a polishing holder according to Comparative Example 1. FIG.

Hereinafter, modes for carrying out the present invention (hereinafter, simply referred to as “the present embodiment”) will be described in detail.

[Holder for polishing]
The polishing holder of the present embodiment is directly bonded to a back pad for holding an object to be polished (hereinafter, also referred to as “work”) and surrounds the object to be polished. And a frame material for. In the present specification, “directly bonded” means that the back pad and the frame member are bonded to each other without an adhesive agent interposed therebetween. The adhesive means various known adhesive materials, and specific examples thereof include hot-melt adhesives, thermosetting adhesives and pressure-sensitive adhesives, and also natural adhesives such as glue. In the polishing holder of the present embodiment, by directly joining the back pad and the frame material, (1) due to the acidic slurry between the back pad and the frame material and the friction heat generated during polishing, There is no intervening adhesive agent that easily deteriorates or shrinks the back pad, and (2) the only cause of peeling is the interface destruction between the frame material and the back pad. As a result, in the polishing holder of the present embodiment, peeling inside is suppressed. For example, even when the back pad and the frame member are made of different materials and the heat shrinkage rate and the amount of compressive deformation as a whole have a gradient, the present embodiment relates to the above (1) and (2). Due to the characteristics, peeling inside the polishing holder is suppressed.

The structure of the polishing holder according to this embodiment is illustrated in FIG. As shown in FIG. 1A, which is a plan view, and FIG. 1B, which is a cross-sectional view showing an I-I cross section of the plan view, the polishing holder 10 includes a substantially circular back pad 12 and an annular frame. The material 14 is laminated and provided, and the frame material 14 may be provided on the outer edge portion on the back pad 12. The frame member 14 is directly bonded to the back pad 12.

(Back pad)
The back pad in the present embodiment is not particularly limited in material and shape as long as it holds a work (has a holding surface). The back pad is preferably in the form of a sheet, in which case the surface of the sheet serves as the holding surface. However, the shape of the back pad is not limited to the sheet shape.

The back pad preferably has an appropriate amount of water in its holding surface and presses the object to be polished so that the holding surface interacts with the surface of the object to be polished, and when there is an opening in the surface of the holding surface. It can be held by the adsorption force due to the opening and the surface tension of water. The holding surface of the back pad may be designed to be slightly larger than the surface of the object to be polished that contacts the back pad so that the object to be polished can be easily held. Further, the back pad may be configured to hold a plurality of objects to be polished at the same time. In the present embodiment, the back pad preferably contains an elastic resin foam from the viewpoint of suppressing the occurrence of polishing scratches on the surface of the polishing object due to the impact during polishing.

In the present embodiment, the “elastic resin foam” means an elastic resin and a plurality of bubbles existing in the elastic resin. With such a structure, the elastic resin foam can absorb the impact that the object to be polished receives from the polishing pad during polishing. Therefore, the occurrence of polishing scratches on the surface of the polishing object due to the impact during polishing tends to be effectively suppressed. Hereinafter, the structure of the elastic resin foam will be described in more detail.

(Elastic resin)
The elastic resin is not particularly limited, but examples thereof include polyurethane resin, polynorbornene resin, trans-polyisoprene resin, and styrene-butadiene resin. Among these, a polyurethane resin is preferable from the viewpoints of hardness, viscoelastic property adjustment, good foamability, and wear resistance. These may be used alone or in combination of two or more.

The polyurethane resin is not particularly limited, but when it is produced by a wet coagulation method, examples thereof include a polyester polyurethane resin, a polyether polyurethane resin, and a polycarbonate polyurethane resin. These may be used alone or in combination of two or more. Among them, the polyether polyurethane resin is preferable from the viewpoint of more effectively and surely achieving the object of the present embodiment.

The polyurethane resin may be synthesized by a conventional method, or a commercially available product may be obtained. The commercially available product is not particularly limited, and examples thereof include SMP (trade name of SMP Technologies Co., Ltd.), Diaplex (trade name of Mitsubishi Heavy Industries, Ltd.), Crisbon (trade name of DIC Co., Ltd.) , Sampren (trade name, manufactured by Sanyo Chemical Industry Co., Ltd.), and Resamine (trade name, manufactured by Dainippon Seika Chemicals Co., Ltd.).

The polynorbornene resin may be synthesized by a conventional method, or a commercially available product may be obtained. The commercially available product is not particularly limited, and examples thereof include Nosolex (trade name of Nippon Zeon Co., Ltd.).

The trans-polyisoprene resin may be synthesized by a conventional method or a commercially available product may be obtained. The commercially available product is not particularly limited, and examples thereof include Kuraray TPI (trade name, manufactured by Kuraray Co., Ltd.).

The styrene-butadiene resin may be synthesized by a conventional method, or a commercially available product may be obtained. The commercially available product is not particularly limited, and examples thereof include Asmer (trade name, manufactured by Asahi Kasei Co., Ltd.).

As the elastic resin, a polyurethane resin is preferable from the viewpoint of easy availability and processing, and more effectively and reliably achieving the object of the present embodiment. The content of the polyurethane resin is preferably 50% by mass or more, more preferably 80% by mass or more, further preferably 90% by mass or more, particularly preferably 95% by mass, based on the total amount of the elastic resin. That is all.

On the other hand, the elastic resin may be manufactured by a molding method. When a polyurethane resin is produced by a molding method, for example, a mixed solution is prepared in which an isocyanate group-containing compound and an active hydrogen compound having an active hydrogen group that reacts with a terminal isocyanate group of the isocyanate group-containing compound are mixed. The isocyanate group-containing compound can be produced by reacting a polyol compound having two or more hydroxyl groups in the molecule with a diisocyanate compound having a diisocyanate group having two isocyanate groups in the molecule. The obtained mixed liquid is cast into a mold, and the isocyanate group-containing compound and the active hydrogen compound are reacted and cured in the mold to form a block-shaped polyurethane molded body. This polyurethane molded body is sliced into a sheet to form a urethane sheet. Further, instead of slicing the block-shaped urethane molded body, it is also possible to mold each urethane sheet having a desired thickness by changing the mold size.

In addition to the elastic resin, the elastic resin foam may contain one or more other additives as required. Examples of such additives include, but are not limited to, foaming agents, catalysts, surfactants, antioxidants, antistatic agents, hydrophilic agents, hydrophobic agents, dyes and pigments.

(Air bubbles)
In the present embodiment, the bubbles present in the elastic resin foam are not particularly limited, but, for example, closed cells in which a plurality of bubbles independently exist, continuous cells in which a plurality of bubbles are connected by a communication hole, and tear-shaped Bubbles are mentioned, and these may be mixed. Among these, it is preferable that the elastic resin foam has closed cells. For example, when polishing an object to be polished, a slurry containing a strong oxidant or the like may be used in order to make the surface of the object to be polished easily polished. At this time, the presence of closed cells can prevent the strong oxidant from penetrating into the elastic resin foam, so that the deterioration of the elastic resin foam due to the strong oxidant tends to be effectively suppressed. It is in. Therefore, the chemical resistance of the elastic resin foam having closed cells tends to be further improved. On the other hand, the use of open cells is preferable from the viewpoint of easily ensuring the cushioning property and the adhesiveness (holding performance) required for the back pad. Further, it is preferable to have tear-shaped bubbles formed by the wet film formation method from the viewpoint of easily securing the cushioning property and the adhesiveness (holding performance) required for the back pad.

When the cells are closed cells, the elastic resin foam may include an elastic resin and a plurality of resin hollow fine particles dispersed in the elastic resin. In this case, the hollow fine particles have a resin outer shell, and bubbles are formed in the outer shell.

As the hollow fine particles, commercially available products may be obtained, or those obtained by synthesizing by a conventional method may be used. As a material for the outer shell of the hollow fine particles, a synthetic resin is preferable from the viewpoint of excellent flexibility and easy compression deformation, and more specifically, polyvinyl alcohol, polyvinylpyrrolidone, poly(meth)acrylic acid. , Polyacrylamide, polyethylene glycol, polyhydroxy ether acrylite, maleic acid copolymer, polyethylene oxide, polyurethane, poly(meth)acrylonitrile, polyvinylidene chloride, polyvinyl chloride and organic silicone resins, and resins thereof A copolymer in which two or more kinds of monomers are combined can be used. The commercially available hollow fine particles are not particularly limited, and examples thereof include Expancel series (trade name of Akzo Nobel Co., Ltd.) and Matsumoto Microspheres (trade name of Matsumoto Yushi Co., Ltd.). Among these, those having excellent flexibility are preferable, and specifically, a copolymer of (meth)acrylonitrile and vinylidene chloride and methyl methacrylate are preferable, and from the viewpoint of further excellent flexibility, (meth ) A copolymer of acrylonitrile and vinylidene chloride is more preferable. These may be used alone or in combination of two or more.

The shape of the bubbles is not particularly limited, and examples thereof include a spherical shape, a substantially spherical shape, a flattened shape in the surface direction of the elastic resin foam (flat shape), and a teardrop shape.

The bubbles having a spherical shape, a substantially spherical shape, or a shape flattened in the surface direction of the elastic resin foam can be formed by, for example, a molding method described later. Tear-shaped bubbles can be formed by, for example, a conventionally known wet coagulation method.

When the elastic resin foam is formed by the molding method, the average cell diameter of the elastic resin foam is preferably 10 to 150 μm, more preferably 15 to 145 μm, and further preferably 20 to 140 μm. When the average diameter of the bubbles is 10 μm or more, it tends to be possible to further suppress the occurrence of polishing scratches on the surface of the polishing object due to the impact during polishing. Further, when the average diameter of the bubbles is 150 μm or less, the amount of slurry permeation into the bubbles is small, and therefore the chemical resistance of the elastic resin foam to the slurry tends to be further improved. The average diameter of the bubbles can be adjusted, for example, by controlling the diameter of the hollow fine particles used in the molding method described later. The average diameter of bubbles is measured by magnifying and observing the cross section with a scanning electron microscope or the like.

The density (bulk density) of the elastic resin foam is preferably 0.16 to 1.0 g/cm ³ , more preferably 0.30 to 0.90 g/cm ³ , and further preferably 0.35 to 0.35 g/cm ^3. It is 0.70 g/cm ³ . Since the elastic resin foam has a density of 0.16 g/cm ³ or more, even when the elastic resin foam is processed under a high polishing pressure, the sinking is suppressed, and a higher degree of flatness of the object to be polished tends to be achieved. is there. Further, when the density of the elastic resin foam is 1.0 g/cm ³ or less, the occurrence of polishing scratches on the surface of the polishing object due to the impact during polishing tends to be further suppressed. The density can be adjusted, for example, by controlling the amount of bubbles contained in the elastic resin foam. The density can be measured according to JIS-K-7222 (2005).

The elastic resin foam may have openings on its surface (work holding surface). The openings are formed by exposing air bubbles in the elastic resin foam to the surface, and are formed by slicing or buffing the elastic resin foam. Therefore, when the elastic resin foam is formed by the molding method, the size of the openings depends on the size of the bubbles.

When the elastic resin foam has pores on its surface, the surface pore size is preferably 10 to 150 μm, more preferably 15 to 145 μm, and further preferably 20 to 140 μm. When the surface pore diameter of the elastic resin foam is within the above range, the object to be polished tends to be easily attached to and detached from the work holding surface. The surface pore size can be adjusted, for example, by controlling the diameter of the hollow fine particles used in the molding method described later, or by the content of water that plays a role of a foaming agent, stirring conditions during production, and the like. The surface pore size can be measured by the method described in Examples. On the other hand, when the elastic resin foam does not have openings, the adhesion of the elastic resin foam to the object to be polished can be increased, and the holding performance of the object to be polished can be improved.

(Various physical properties of back pad)
In the present embodiment, the hardness of the back pad is preferably Shore A hardness 10° or more and Shore D hardness 70° or less, more preferably Shore A hardness 10° or more and Shore A hardness 80° or less, and further preferably shore. A hardness is 10° or more and Shore A hardness is 50° or less. When the Shore A hardness is 10° or more, sinking of the back pad is suppressed when polishing is performed with a high polishing pressure, and a higher degree of flatness of the object to be polished tends to be achieved. Further, when the Shore D hardness is 70° or less, it tends to be possible to further suppress the occurrence of polishing scratches on the surface of the polishing object due to the impact during polishing. The hardness of the back pad can be adjusted, for example, by controlling the amount of bubbles contained in the elastic resin foam as the back pad. The Shore A hardness and the Shore D hardness can be measured according to JIS-K-6253 (2012).

The compressibility of the back pad is preferably 0.10 to 40%, more preferably 0.40 to 25%, and further preferably 1.0 to 10%. When the compressibility of the back pad is 0.10% or more, the occurrence of polishing scratches on the surface of the polishing object due to the impact during polishing tends to be further suppressed. Moreover, when the compressibility of the back pad is 40% or less, the polishing rate tends to be further improved. The compressibility is, for example, the type and degree of polymerization of the prepolymer used for preparing the elastic resin foam as the back pad, the amount of water or non-reactive gas to be mixed in the mixed solution, the hollow fine particles, the chemical foaming agent, and the water-soluble fine particles. It can be adjusted by the amount of foaming. The compression rate can be measured by the following method. The fact that the back pad contains the elastic resin foam can be confirmed, for example, from the fact that the compression rate is 0.10 to 40%.

The compressibility can be determined by using a Shopper type thickness measuring device (pressurized surface: a circle having a diameter of 1 cm) according to Japanese Industrial Standards (JIS L 1021). Specifically, the thickness t ₀ after over 30 seconds initial load from a no-load state is measured, then the thickness t ₁ after applying a final pressure of 60 seconds from the state of the thickness t ₀ taking measurement. The compression rate is calculated by the equation of compression rate (%)=100×(t ₀ −t ₁ )/t ₀ . At this time, the initial load is 300 g/cm ² and the final pressure is 1800 g/cm ² .

The compression elastic modulus of the back pad is preferably 55 to 100%, more preferably 60 to 100%, and further preferably 65 to 100%. When the compression elastic modulus of the back pad is 55% or more, the occurrence of polishing scratches on the surface of the polishing object due to the impact during polishing tends to be further suppressed. The compression elastic modulus is, for example, the type and degree of polymerization of the prepolymer used in the production of the elastic resin foam as the back pad, the amount of water or non-reactive gas compounded in the mixed solution, the hollow fine particles, the chemical foaming agent, and the water solubility. It can be adjusted by the amount of foaming by the fine particles. The compression modulus can be measured by the following method. In addition, it can be confirmed that the back pad contains the elastic resin foam, for example, because the compression elastic modulus is 55 to 100%.

The compressive elastic modulus can be determined according to Japanese Industrial Standards (JIS L 1021) using a Shopper type thickness meter (pressurized surface: circular shape having a diameter of 1 cm). Specifically, the thickness t ₀ after over 30 seconds initial load from a no-load state is measured, then the thickness t ₁ after applying a final pressure of 60 seconds from the state of the thickness t ₀ taking measurement. All the loads are removed from the state of the thickness t ₁ , left for 60 seconds (no load), and the initial load is applied for 30 seconds again, and the thickness t ₀ ′ is measured. The compression elastic modulus is calculated by the formula of compression elastic modulus (%)=100×(t ₀ ′−t ₁ )/(t ₀ −t ₁ ). At this time, the initial load is 300 g/cm ² and the final pressure is 1800 g/cm ² .

The thickness of the back pad is not particularly limited, but is preferably 0.10 to 5.0 mm, more preferably 0.20 to 2.5 mm, and further preferably 0.30 to 1.5 mm. When the thickness of the back pad is 0.10 mm or more, the amount of compressive deformation is further improved, the holding performance (adhesion) of the object to be polished is improved, and the impact on the object to be polished is absorbed during polishing. Then, defects such as breakage tend to decrease. Further, when the thickness of the back pad is 5.0 mm or less, the flatness deterioration and the polishing rate decrease due to the excessively large amount of compressive deformation tend to be suppressed. Particularly, when the thickness of the object to be polished is thin and the thickness of the frame material is 500 μm or less, higher polishing accuracy is required. Therefore, by setting the thickness of the back pad to 1.5 mm or less, the flatness is improved. And the polishing rate tend to be compatible. The thickness of the back pad means the distance from the surface of the back pad that contacts the surface plate to the work holding surface of the back pad, and is measured in accordance with Japanese Industrial Standards (JIS K 6505). When an adhesive layer such as a double-sided tape is provided on the surface in contact with the surface plate, a well-known image processing technique or the like is used together to subtract the thickness of the adhesive layer.

(Frame material)
The frame material in the present embodiment prevents lateral displacement of the object to be polished during polishing and prevents the object from falling off the work holding surface of the back pad (regulating the lateral displacement range). Therefore, the frame member is provided on the surface around the work holding surface of the back pad. The shape and dimensions of the frame material are not particularly limited as long as the object to be polished does not jump out of the polishing region.For example, in the case of a circular object to be polished, the frame material has an inner diameter larger than that of the object to be polished. It may have a slightly large circular shape, that is, it may have a holding hole. Further, the frame material may be a resin non-foamed body having no bubbles inside from the viewpoint of hardness, chemical resistance and accuracy required at the time of polishing, or may be foamed within a range not impairing the function as the frame material. May be included. For example, durability and chemical resistance tend to be improved if the average aperture diameter when measuring the aperture diameter on the surface of the frame material is 10 μm or less, and it is more preferable if the average aperture diameter is 5 μm or less, and the average aperture diameter is 5 μm or less. Is more preferably 2 μm or less. The method for measuring the aperture diameter may be a known method, for example, it is measured as follows. The image is obtained by observing with a laser microscope (for example, trade name "VK-X105" manufactured by KEYENCE) at 200 times magnification. Next, the obtained image is binarized by image analysis software (for example, product name “WinRof” manufactured by Mitani Shoji Co., Ltd.) to distinguish the aperture from the other portions. Then, the equivalent circle diameter is calculated from the area of each of the distinguished openings, that is, the opening diameter is calculated on the assumption that the opening is a perfect circle. Then, the aperture diameters of the respective apertures are arithmetically averaged to obtain an average aperture diameter (μm).

The thickness of the frame material is not particularly limited, and may be equal to or less than the thickness of the object to be polished (for example, the object W to be polished shown in FIG. 3) or equal to the thickness of the object to be polished. For example, when the thickness of the frame material is equal to the thickness of the object to be polished, the frame material comes into contact with the polishing pad by pressing the polishing pad during polishing. By pressing the polishing pad with the frame material, the flatness of the polishing pad surface in contact with the object to be polished is improved, and as a result, uneven polishing, particularly edge sag tends to be further suppressed. In the present embodiment, when the frame material is formed by printing described later, the thickness of the frame material is preferably 500 μm or less, and more preferably 50, from the viewpoint of ensuring the accuracy and strength required for the frame material. ˜450 μm, and more preferably 100 to 400 μm. The thickness of the frame material means the distance from the surface of the frame material that contacts the back pad to the surface of the frame material that contacts the polishing pad, and is measured according to Japanese Industrial Standards (JIS K 6505). The thickness of the frame material can be easily adjusted in a forming process such as screen printing described later, for example.

The polishing holder of the present embodiment preferably has a groove in the frame material from the viewpoint of improving the fluidity of the slurry. The groove is formed so as to open at least on the surface of the polishing holder facing the polishing pad at the time of polishing, and may penetrate the frame member or may not penetrate it. .. When it is penetrated, it may have a groove depth reaching a part of the back pad. The formation of the groove can be easily performed in a forming process such as screen printing described later, and the shape of the groove can be easily adjusted in the same manner. A known method such as grinding may be used, or a plurality of means may be used in combination.

FIG. 2 illustrates a mode in which the polishing holder according to the present embodiment has the groove portion. As shown in FIG. 2A, which is a plan view, and FIG. 2B, which is a cross-sectional view showing a II-II cross section of the plan view, the polishing holder 20 includes a substantially circular back pad 22 and an annular ring. Is laminated and provided at four places with the frame member 24 having a shape divided into four by the groove portion 26. The frame member 24 is provided on the outer edge portion of the back pad 22. From the viewpoint of improving the fluidity of the slurry, the number of groove portions is not particularly limited, and the number of groove portions may be only one. Also in this example, the frame member 24 is directly bonded to the back pad 22. As described above, the polishing holder 20 is configured to have the groove portion 26 in which at least the opening is formed on the surface of the frame member 24 facing the polishing pad at the time of polishing.

The main component as the frame material in the present embodiment is not limited to the composition and the drying method as long as it is a synthetic resin having a coatable property, and various known resins can be applied. The synthetic resin is not limited to the following, but may include, for example, one or more resins selected from the group consisting of a thermoplastic resin, a thermosetting resin, a photocurable resin, and an electron beam curable resin. Synthetic resins that can be used include acrylic resins, urethane resins, epoxy resins, phenol resins, fluororesins, and the like. Even if two or more of these resins are copolymerized or mixed, as described above. Good. The “main component” means a component contained in the frame material in an amount of 50% by mass or more.
In the step of forming a frame material, a frame material can be formed by drying and solidifying by evaporating the solvent by using a solvent such as water or various organic solvents in combination, but the volume contraction occurs due to the evaporation of the solvent. In some cases, the film thickness and shape as set may not be obtained. Therefore, particularly when a constant film thickness or shape is required, it is preferable to use a one-part or two-part or more reactive resin composition having no solvent or a large solidification component ratio.
Further, from the viewpoint of heat resistance, the frame material in the present embodiment preferably contains a thermosetting resin, a photocurable resin or an electron beam curable resin, and a viewpoint of increasing the solvent-free or solidification component ratio, the frame material is required. From the viewpoint of hardness, viscoelasticity, chemical resistance, and control of the curing process, it is more preferable to include a photocurable resin or an electron beam curable resin, equipment cost and production simplicity, and a commercially available resin From the viewpoint of versatility, UV (ultraviolet) curable resins are more preferable. Examples of the UV curable resin include, but are not limited to, thiol-based resins and epoxy-based resins, urethane-based resins, polyester-based resins, and the like. Examples of the thiol resin include, but are not limited to, Thiokol LP (manufactured by Toray Fine Chemical Co.) and the like. The epoxy resin is not limited to the following, but examples thereof include HUG (manufactured by Seiko Advance Co., Ltd.). Examples of the urethane-based resin include, but are not limited to, V-9500 (manufactured by DIC) and UV FIL (manufactured by Teikoku Ink Co.). Further, examples of the thermosetting resin include an epoxy resin and a urethane resin. Examples of the epoxy resin include, but are not limited to, Epicron (manufactured by DIC) and the like. Examples of the urethane resin include, but are not limited to, SS-16 (manufactured by Toyo Ink Co., Ltd.) and the like. Examples of the thermoplastic resin include, but are not limited to, polyester resins and acrylic resins. Examples of the electron beam curing resin include, but are not limited to, urethane resins and epoxy resins, thiol resins, polyester resins, and polyether resins. In consideration of hardness, heat resistance, chemical resistance, etc. required for the polishing step, the frame material in the present embodiment is made of one or more resins selected from the group consisting of thiol-based resins, epoxy-based resins and urethane-based resins. It is particularly preferable to include.

The frame material in the present embodiment preferably does not contain glass fiber. Conventionally, it is generally known that the frame material contains glass fibers, but when such a frame material is used, due to the exposure or dropping of the glass fibers due to the wear of the frame material, the material to be polished is Scratches may occur. From the viewpoint of preventing such scratches, the frame material preferably does not contain glass fibers. In addition to glass fibers, even fibers such as natural fibers, synthetic fibers, and carbon fibers may adhere as foreign matter to the ends or steps of the object to be polished. Therefore, from the viewpoint of more effectively preventing the mixing of such foreign matter, the frame material should not include, in addition to the glass fibers, one or more fibers selected from the group consisting of natural fibers, synthetic fibers, and carbon fibers. Is more preferable. In addition, it is preferable that the frame material does not include a glass fiber reinforced epoxy resin that is conventionally generally used for a frame material as a material including glass fiber. Further, in consideration of application to a thin object to be polished, it is preferable to make the frame material thin, so that deterioration of thickness accuracy and warpage that may occur due to processing of a resin containing hard fibers (for example, glass fiber reinforced epoxy resin) may occur. From the viewpoint of prevention, it is preferable that the frame material in the present embodiment does not contain glass fiber, and in addition to the glass fiber, at least one fiber selected from the group consisting of natural fiber, synthetic fiber and carbon fiber is also included. Preferably not.

[Method for manufacturing polishing holder]
The method for manufacturing the polishing holder of the present embodiment is a method for manufacturing a polishing holder that includes a back pad for holding an object to be polished, and a frame material for surrounding the object to be polished, There is a forming step of directly joining the frame member on the back pad. Because of the above-described configuration, the polishing holder of the present embodiment can preferably manufacture the polishing holder of the present embodiment.

In the method for manufacturing the polishing holder of the present embodiment (hereinafter, also simply referred to as “manufacturing method”), for example, the back pad can be obtained as follows. That is, the manufacturing method of the present embodiment includes a foam forming step of forming a foam having the elastic resin described above and a plurality of bubbles existing in the elastic resin.

[Foam forming step]
The foam forming step is a step of forming a foam having an elastic resin and a plurality of bubbles existing in the elastic resin. Examples of the foam forming method include a method of forming a foam by a molding method.

(Mold molding method)
First, a method of forming a foam by a molding method will be described. The method of forming bubbles in the molding method is not particularly limited and may be a conventionally known method. For example, the hollow fine particles are dispersed in an elastic resin, or a chemical foaming agent is mixed in the elastic resin for gas foaming, or the elastic resin and an inert gas are kneaded under pressure to foam under reduced pressure to form bubbles. The method of forming may be mentioned.

Hereinafter, the molding method when hollow polyurethane particles are used and polyurethane resin is adopted as the elastic resin will be described. Specifically, a polyurethane resin foam is formed from a mixed liquid obtained by mixing an isocyanate group-containing compound, an active hydrogen compound, and hollow hollow particles having an outer shell.

First, an isocyanate group-containing compound and an active hydrogen compound that are raw materials for a polyurethane resin, hollow fine particles used as a raw material (hereinafter referred to as "raw material hollow fine particles"), and other materials to be included in an elastic resin foam, if necessary. (For example, a foaming agent, a catalyst, a surfactant, an antioxidant, an antistatic agent, a hydrophilic agent, a hydrophobic agent, a dye and a pigment, etc.) are mixed to prepare a mixed solution. At this time, in order to make the dispersion state of the raw material hollow fine particles in the mixed solution uniform, it is preferable to preliminarily and substantially uniformly mix and disperse with the isocyanate group-containing compound or the active hydrogen compound.

As the isocyanate group-containing compound, an isocyanate-terminated urethane prepolymer produced by reacting a polyol compound having two or more hydroxyl groups in the molecule with a diisocyanate compound having two isocyanate groups in the molecule (hereinafter, simply, Abbreviated as "prepolymer") is preferable. When reacting the polyol compound and the diisocyanate compound, the prepolymer can be obtained by making the molar amount of the isocyanate group larger than the molar amount of the hydroxyl group.

If the prepolymer has too high a viscosity, the fluidity of the prepolymer decreases, and it becomes difficult to mix the prepolymer substantially uniformly. On the other hand, when the temperature is raised to lower the viscosity, the pot life becomes shorter (the curing reaction of the prepolymer becomes faster), and mixing spots occur rather, and the dispersion state of the hollow fine particles varies. In addition, when the hollow fine particles contain an expanding agent, the expanding agent may foam due to a temperature rise, which may cause variations in the size and dispersed state of the bubbles. On the other hand, when the viscosity is too low, the hollow fine particles move in the mixed liquid, and it becomes difficult to disperse the hollow fine particles in the obtained polyurethane-forming body substantially evenly and substantially uniformly. Therefore, the prepolymer preferably has a viscosity at a temperature of 50 to 80° C. in the range of 500 to 4000 mPa·s. To set the viscosity within this range, for example, the molecular weight (degree of polymerization) of the prepolymer may be controlled. The prepolymer is heated at a temperature of about 50 to 80° C. and becomes in a flowable state.

The raw material hollow fine particles finally become bubbles contained in the elastic resin foam. The raw material hollow fine particles are hollow ones having an outer shell, and may be unexpanded hollow fine particles having a foaming component in the hollow portion, or may be preexpanded hollow fine particles subjected to expansion treatment, It may be a mixture thereof. It may have an expanding agent that generates gas to form bubbles during formation of the polyurethane forming body. The expanding agent content is not particularly limited.

The swelling agent is a solid or liquid at room temperature, and is preferably selected from the group consisting of a chemical foaming agent that thermally decomposes at 100° C. to 260° C. to generate a decomposed gas, a water-soluble substance retaining water, and water. At least one component is used. Bubbles are formed by the gas generated by the decomposition and vaporization of the expanding agent when the polyurethane molded body is formed. In the case of a water-soluble substance, the slurry at the time of polishing can dissolve the water-soluble substance on the polishing surface to form openings.

Examples of the chemical foaming agent include barium azodicarboxylate, N,N′-dinitrosopentamethylenetetramine, sodium hydrogen carbonate, azodicarbonamide, 4,4′-oxybisbenzenesulfonylhydrazide and hydrazodicarbonamide. At least one selected from the group can be used. When the thermal decomposition temperature of the chemical foaming agent is 100° C. or higher, early decomposition is further suppressed during formation of the polyurethane molded body, and the dispersed state of bubbles can be made more even and uniform, and it is 260° C. or lower. In addition, when the polyurethane-formed product is formed, it can be decomposed more favorably and bubbles can be formed more easily.

As the water-soluble substance, for example, water-soluble polysaccharides such as carboxymethyl cellulose, hydroxypropyl cellulose, carboxymethyl chitin, dextrin and cyclodextrin and derivatives thereof, oligosaccharides and monosaccharides such as chitooligosaccharides, fructooligosaccharides, sucrose and glucose. Alkali components or neutral salts such as potassium hydroxide, sodium hydroxide, rubidium hydroxide, cesium hydroxide, potassium acetate, potassium nitrate, potassium carbonate, potassium hydrogen carbonate, potassium chloride, potassium bromide and potassium phosphate; aliphatic; Cationic surfactants such as amine salts and aliphatic ammonium salts; anionic surfactants such as alkylbenzene sulfonates, sulfonates, alkyl ether sulfates and phosphate ester salts; ether type, ether ester type and ester type surfactants Nonionic surfactants such as; amino acids, proteins, polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl sulfonic acid, and poly(meth)acrylic acid. These may be used alone or in combination of two or more. Since these water-soluble substances easily retain water, the water retained in the water-soluble substance reacts with the isocyanate group-containing compound during formation of the polyurethane-forming body to generate gas and bubbles are formed.

Then, the isocyanate group-containing compound and the active hydrogen compound in the mixed liquid are reacted and cured to form a block-shaped polyurethane resin foam. At this time, the isocyanate group-containing compound is cured by the reaction (polymerization or crosslinking) with the active hydrogen compound. Usually, since the upper part of the mold forming the polyurethane resin foam is open, curing by reaction (polymerization/crosslinking) proceeds under atmospheric pressure to form a polyurethane resin foam having an elastic resin. .. Further, when the raw material hollow fine particles are unexpanded hollow fine particles, the reaction heat generated by this reaction causes the expander present in the hollow portion of the unexpanded hollow fine particles to generate gas or vaporize and expand, thereby forming hollow fine particles. It is formed. On the other hand, when the raw material hollow fine particles are already expanded hollow fine particles, since the expansion treatment has already been performed, the already expanded hollow fine particles are the hollow fine particles as they are, or the air bubbles therein are slightly expanded and the hollow fine particles are expanded. Becomes Since the raw material hollow fine particles are substantially evenly and substantially uniformly dispersed in the mixed solution, crosslinking and hardening proceed around the raw material hollow fine particles. Thereby, in the polyurethane formed body, the hollow fine particles and the bubbles present therein are formed substantially uniformly and substantially uniformly in the elastic resin.

The content ratio of the isocyanate group-containing compound in the mixed solution is not particularly limited, but from the viewpoint of more effectively and reliably producing the effect of the present embodiment, the molar ratio (equivalent ratio) is 0.80 with respect to the active hydrogen compound. It is preferable that it is -1.2, and it is more preferable that it is 0.90-1.1.

The above process may be continuously performed using a conventionally known apparatus for forming a polyurethane resin foam. Further, although the manufacturing method by the molding method is exemplified, the polyurethane resin foam may be formed by a conventionally known wet coagulation method.

(Frame material forming process)
The forming step of directly joining the frame material to the back pad in the present embodiment is not particularly limited as long as the back pad and the frame material are directly joined.

More specifically, in the present embodiment, a method of impregnating, penetrating or dissolving and solidifying a part of the frame material with respect to a part of the back pad, or a part of the back pad with respect to a part of the frame material. Etc. As a result, the back pad and the frame material are entangled or mixed with each other at a part thereof, so that they can be strongly bonded. Further, a part of the frame material may be directly bonded to the back pad via intermolecular force or covalent bond.
In this way, since the frame material and the back pad are directly bonded, the only factor that can cause peeling is "interfacial destruction between the frame material and the back pad", and elastic deformation (pressurization) occurs. The bonding process is also unnecessary. Therefore, even if the frame material is thin and the back pad and the frame material have different physical properties such as hardness, compressibility, and heat shrinkability, the occurrence of warpage and peeling can be suppressed, and the frame material and the back pad can be suppressed. Physical properties can be designed individually.

In the present embodiment, it is preferable that the frame material is formed of a photocurable resin, and that the above-mentioned forming step includes a step of printing the photocurable resin. A publicly known method can be adopted as a specific printing method, and the printing method is not limited to the following, and examples thereof include screen printing, letterpress printing, intaglio printing, offset printing, and inkjet printing. Among these, screen printing is preferable from the viewpoints of easy production of small quantities of various kinds, easy formation of surface shapes such as grooves, equipment cost, productivity, variety of corresponding resins, thickness and accuracy. That is, in the polishing holder of the present embodiment, the frame material is preferably formed by screen printing on the back pad. Screen printing is a method of forming a pattern through an extremely fine mesh (screen) typically called gauze. By applying screen printing to the forming step in the present embodiment, it is possible to preferably form a (thin) frame material having a small thickness (several tens μm to several hundreds μm) on the back pad. Conventionally, when the object to be polished is thin, instead of or in addition to arranging the frame member on the back pad, the back pad is attached in the holding through hole of the frame member, and the thickness difference is used. Compatible (so-called insert type). However, in this case, since it is necessary to attach a back pad having a size equal to the opening size of the holding through hole, if the position where the back pad is attached is shifted, the back pad will be attached to part of the frame material and The holding surface may be inclined or curved, or may be bitten by air and rise up, or the back pad may be peeled off and re-attached, which involves complicated work. On the other hand, by applying the screen printing according to the present embodiment, it is possible to prevent the holding surface of the back pad from tilting or curving when dealing with a thin object to be polished, simplify the complicated work, and reduce the manufacturing cost. Not only that, the frame material can be made thinner accurately (prevention of warpage of the frame material). Further, since the bonding step is unnecessary, the manufacturing cost can be reduced. Furthermore, according to the screen printing, the shape of the frame material to be formed can be easily adjusted by setting the screen. Therefore, even when the groove is provided in the frame member described above, the frame member provided with the groove can be easily formed.

Examples of the screen-printing step include selecting a silk screen gauze count and selecting a silk screen gauze so that a desired design can be printed and a desired thickness can be obtained after the frame material is printed. A step of creating a silk screen including a design transfer (a step of masking a non-printed portion and melting a mask of a printed portion), a step of preparing a slurry containing a raw material of a frame material such as a curable resin, and the slurry It may include a step of applying the slurry on the back pad through a screen and a step of curing the applied slurry. The silk screen gauze is not limited to those containing natural fibers such as silk, but may include synthetic fibers such as polyester and metal fibers such as stainless steel, and other known screen gauze can be used according to the required performance. .. The step of adjusting the slurry may include, for example, a step of mixing, stirring, and defoaming the precursor of the curable resin and the curing agent. Further, a solvent may be added to adjust the viscosity of the slurry, but from the viewpoint of preventing volumetric shrinkage due to evaporation of the solvent, it is preferable that the addition amount of the solvent be as small as possible. Examples of the solvent include, but are not limited to, toluene, methyl ethyl ketone, isophorone, and xylene. In addition, a known additive such as a thickener, a water repellent, a hydrophilic agent, or a pigment such as carbon black may be added to the slurry, if necessary. Further, any printing or coating process (for example, anchor coating or water repellent surface treatment) may be provided before or after the frame material printing, depending on the required physical properties. Conditions for the step of curing the slurry can be appropriately set according to the resin used, but for example, steps such as heating, drying, UV (ultraviolet) irradiation, EB (electron beam) irradiation, cooling, and standing can be performed. May be included.

Further, in the forming step of the present embodiment, the frame material is a material of the frame material (for example, photocurable polyurethane) or a precursor thereof (for example, thermosetting polyurethane prepolymer) in the mold placed on the back pad. And its curing agent), and may be formed by drying the material or curing the precursor. That is, in the polishing holder of the present embodiment, the frame material is formed by filling the material of the frame material or the precursor thereof into the mold placed on the back pad and drying the material or curing the precursor. can do. The shape of the mold may be arbitrary according to the desired shape of the frame material.

[Lamination process]
The method for manufacturing the polishing holder of the present embodiment may further include a laminating step of bonding the base material to the surface of the back pad opposite to the surface on which the frame material is formed. The composite of the polishing holder and the base material thus obtained is also referred to as a holder sheet. The laminating method is not particularly limited, and examples thereof include a method of laminating via an adhesive layer. Further, the method may further include a step of laminating a release layer on the surface of the base material opposite to the surface on which the back pad is laminated, with an adhesive layer interposed therebetween. Examples of the base material include, but are not limited to, a urethane sheet obtained by a wet coagulation method, a urethane sheet obtained by a molding method, a sponge foam such as polyethylene, a film such as polyethylene terephthalate (PET), a nonwoven fabric, and a woven fabric. A cloth or the like can be used. Alternatively, a release layer may be directly laminated on the surface of the elastic resin foam opposite to the surface on which the frame material is formed, without using a base material, with an adhesive layer interposed therebetween.

In the method for manufacturing a polishing holder of the present embodiment, the holder sheet obtained as described above may be used as it is as a polishing holder, and further cut into a desired planar shape. You may use a thing as a holder for polishing. Further, before performing the polishing process using the polishing holder, an inspection such as confirming that the polishing holder is free from dirt, foreign matter, or the like may be performed. Further, a step such as a grinding process may be included to adjust the thickness and shape of the frame material.

[Method for manufacturing abrasives]
The method for manufacturing an abrasive article according to the present embodiment includes a polishing step of polishing an object to be polished held by the above-mentioned polishing holder using a polishing pad to obtain an abrasive article. The polishing step may be primary polishing (rough polishing), finish polishing, or both polishing.

FIG. 3 shows a schematic diagram in the case of polishing an object to be polished using the polishing holder of the present embodiment. First, the polishing holder 10 is attached to the object holder 1 of the polishing machine, and the object W is held by the holder 10. As shown in FIG. 3, the polishing holder 10 holds the workpiece W on the back pad 12 in the frame of the frame member 14. On the other hand, the polishing pad 2 is provided on the polishing platen 3 of the polishing apparatus and is in contact with the object W to be polished. In this state, the object W to be polished can be polished by rotating the polishing pad 2 together with the polishing platen 3.

The object to be polished is not particularly limited, but for example, materials such as semiconductor devices and electronic parts, particularly Si substrate (silicon wafer), SiC (silicon carbide) substrate, GaAs (gallium arsenide) substrate, lens, parallel plate Examples thereof include optical materials such as face plates and reflection mirrors, and thin substrates (objects to be polished) such as substrates for LCDs (liquid crystal displays). Among them, the method for producing an abrasive according to the present embodiment is suitable as a method for producing a material that can be applied to a power device or the like, for example, a difficult-to-process material that is difficult to polish, such as sapphire, SiC, GaN, and diamond. Can be used.

Although the present embodiment has been described in detail above, the present embodiment is not limited to the above contents. For example, the polishing holder of the present embodiment is not limited to the presence or absence of foaming of each member, the back pad is a resin non-foamed body, and the frame material may be a resin foamed body, the back pad and Both of the frame members may be resin foam or resin-free foam. Further, the polishing holder of the present embodiment is not limited to the hardness of the back pad and the frame material, but the frame material has a higher hardness and/or a lower compression rate than the back pad, There is a tendency that both polishing unevenness, particularly edge sag, can be suppressed and the back pad holding performance (adhesiveness) can be made compatible. This means that only the frame part of the polishing holder and only the back pad part are overlapped in the same number so that the total thickness is at least 4.5 mm to prepare a sample for measurement. It can be confirmed by comparing hardness and compressibility. Further, the holding surface of the back pad may be subjected to a known surface treatment with a water repellent, a hydrophilic agent or the like, and the holding surface of the back pad may be subjected to shape processing by a known means such as grinding or pressing.

Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples. The present invention is not limited to the following examples.

[Shore A hardness and Shore D hardness of the back pad]
The Shore A hardness and Shore D hardness of the back pad were measured using an A type hardness meter or a D type hardness meter (manufactured by Teclock Co., Ltd.) according to JIS K 6253 (2012). Specifically, the samples were stacked so that the total thickness was at least 4.5 mm or more to prepare a sample for measurement, and the Shore A hardness and the Shore D hardness of the sample were determined.

[Thickness of frame material]
The thickness of the frame material was measured according to Japanese Industrial Standards (JIS K 6505) using a Shopper type thickness meter (pressurized surface: circular shape having a diameter of 1 cm). Specifically, prepare a sample piece obtained by cutting out a portion of the holder that includes the frame material and a portion that does not include the frame material, set it at a predetermined position of the thickness measuring instrument, and then apply a load of 480 g/cm ² . The applied pressure surface was placed on the surface of the sample piece, and after 5 seconds, measurement was performed to determine the thickness. The thickness of the frame material was calculated by subtracting the thickness of the back pad not including the frame material from the thickness of the portion of the holder including the frame material.

<Polishing test conditions>
The polishing holder was attached to a polishing platen of a single-sided polishing tester via a double-sided tape. An object to be polished was adsorbed (water adsorption) in the holder through water, and a polishing test was performed. More specifically, the polishing test was conducted under the following conditions.
Polishing equipment: Single-sided polishing equipment manufactured by Fujikoshi Machinery Co., Ltd. Polishing object: 8 inch silicon wafer Slurry: Fujimi Incorporated colloidal silica type Slurry flow rate: 600 mL/min
Polishing surface plate rotation speed: 60 rpm
Polishing pressure: 200 gf/cm ²
Polishing time: 60 min x 2 times (2 batches in total)

(Example 1)
The back pad was prepared as follows. That is, a circular back pad having a thickness of 1.3 mm was obtained by molding. The Shore A hardness of this back pad was 20, and it had open cells inside. More specifically, the back pad was obtained as follows. First, as the prepolymer of the first component, 2,4-tolylene diisocyanate, polytetramethylene ether glycol having a number average molecular weight of about 650, and diethylene glycol are reacted at a mass ratio of 39/56/5 to contain an isocyanate group. A urethane prepolymer having an amount of 10% was prepared, heated to 40° C., and defoamed under reduced pressure. MOCA (3,3′-dichloro-4,4′-diaminodiphenylmethane) was used as a second component curing agent and dissolved at 120° C., followed by defoaming under reduced pressure. As a third component curing agent, polytetramethylene ether glycol having a number average molecular weight of about 1000 was heated to 50° C. and defoamed under reduced pressure. As the dispersion liquid of the fourth component, polyethylene glycol having a number average molecular weight of about 200, water, a catalyst (N,N-dimethylpyridin-4-amine), a silicone-based surfactant (trade name "SZ-" manufactured by Dow Corning Co., Ltd.). 1605") was stirred at a compounding ratio (mass ratio) of 85:3:6:6 to prepare a mixture. The first component: the second component: the third component: the fourth component were introduced into the mixer at a mass ratio of 62.9:7.6:26.8:2.7, and the resulting mixed liquid was molded. It was cast in a frame and cured. The formed cured product was extracted from the mold, sliced to a thickness of 1.3 mm, and further cut into a circular planar shape to obtain a circular back pad. Then, urethane-based UV curable resin (trade name "Lake Cure", manufactured by Jujo Chemical Co., Ltd.) is screen-printed on the holding surface of the back pad in an annular shape using a nylon mesh of No. 200 and irradiated with ultraviolet rays for 3 minutes. By doing so, a frame portion made of a non-foamed body was formed by curing, and the polishing holder according to Example 1 was obtained. At this time, the resin thickness (frame material thickness) was set to 200 μm. A double-sided tape was attached to the surface of the back pad on the surface plate side and fixed to the surface plate.

(Comparative example 1)
A holder in which a frame material is bonded with a conventional adhesive is used. The specific manufacturing method was as follows. First, a circular back pad was obtained by wet film formation. The Shore A hardness of this back pad was 25 and the thickness was 0.6 mm. More specifically, the back pad was obtained as follows. First, with respect to 100 parts by mass of a DMF (N,N-dimethylformamide) solution of polyester-based polyurethane resin having a 100% modulus of 10 MPa (concentration 30%), 44 parts by mass of DMF for viscosity adjustment and 3 parts by mass of carbon black. And were mixed to obtain a resin solution. The obtained resin solution was applied to a PET film which is a film-forming substrate to obtain a coating film. The obtained coating film was immersed in a room temperature coagulating bath made of water as a coagulating liquid to coagulate and regenerate the resin to obtain a precursor sheet. A resin obtained by removing the precursor sheet from the coagulation bath, peeling the precursor sheet from the film-forming substrate, and then immersing it in a room temperature cleaning liquid (desolvation bath) to remove DMF as a solvent. The sheet was dried and wound up to obtain a sheet, and the surface was buffed to obtain a back pad. Then, a urethane hot melt adhesive sheet is attached to a frame material (annular shape, thickness 600 μm, Shore D hardness 99 or more (upper limit of measurement)) made of glass fiber reinforced epoxy resin having no bubbles inside, and unnecessary components are cut. Removed. Next, the frame material to which the adhesive sheet was attached was attached to the holding (buffing) surface of the back pad described above, and heat-bonded with a heat press machine to obtain a polishing holder according to Comparative Example 1. A schematic sectional view of the polishing holder according to Comparative Example 1 is shown in FIG. As can be seen from FIG. 4, in the polishing holder according to Comparative Example 1, the frame member 44 was formed on the back pad 42 with the urethane hot melt adhesive sheet 46 interposed therebetween. The surface of the back pad 42 on the surface plate was provided with a double-sided tape (not shown) for adhering to the surface plate.

(Comparative example 2)
A holder in which a frame material is bonded with a conventional adhesive is used. The specific manufacturing method was as follows. First, a circular back pad was obtained in the same manner as in Example 1. Then, a urethane hot melt adhesive sheet was attached to a frame material (annular, thickness 400 μm, Shore D hardness 99 or more (upper limit of measurement)) made of glass fiber reinforced epoxy resin having no bubbles inside, and unnecessary components were cut. Removed. Then, the frame material to which the adhesive sheet was attached was attached to the holding surface of the back pad described above, and heat-bonded with a heat press machine to obtain a polishing holder according to Comparative Example 2. The surface of the holding pad on the surface plate side was provided with a double-sided tape for bonding to the surface plate.

<Results>
In the conventional polishing holders shown in Comparative Examples 1 and 2, after the polishing test, it was visually confirmed that the frame material and the holding surface were partially separated. On the other hand, in the polishing holder of Example 1, no peeling was observed even after the polishing test. Further, when the warp of the holder was visually confirmed, no warp was observed in Comparative Example 1. Although slight warpage was observed in Example 1, there was no problem as a polishing holder. On the other hand, in Comparative Example 2, since the frame material had a relatively small thickness of 400 μm, the internal stress due to the contraction of the adhesive component or the contraction (compression) of the back pad during the hot pressing process exceeded the rigidity of the frame material. Then, the warp that seems to have been confirmed. With this holder, the height of the lift measured above the 5 mm where the horizontal stand and the bottom surface of the holder are the highest among the parts that were lifted due to warping or waviness when placed on a horizontal table The warp was large. With such a holder, workability is poor because the work of sticking to the holding platen without air biting requires careful work, and the holder may peel from the holding platen or the holding surface may wavy. Therefore, it was evaluated as unfavorable.

INDUSTRIAL APPLICABILITY The present invention has industrial applicability as a holder for an object to be polished in the field of polishing.

1 Polishing Object Holder 2 Polishing Pad 3 Polishing Surface Plate 10, 20 Polishing Holder 12, 22, 42 Back Pad 14, 24, 44 Frame Material 26 Groove 46 Urethane Hot Melt Adhesive Sheet W Polishing Object

Claims (8)

A back pad having a holding surface for holding an object to be polished,
A frame member that is directly bonded to the back pad and surrounds the object to be polished,
Equipped with
The frame material is provided on a surface around the holding surface,
The thickness of the frame material, Ru der below 500 [mu] m, the polishing holder. The polishing holder according to claim 1 , wherein the polishing holder has a groove portion in which at least an opening is formed in a surface of the frame material facing the polishing pad during polishing. It said frame member comprises a photocurable resin, abrasive holder according to claim 1 or 2. It said frame member is a thiol-based resin comprises one or more resins selected from the group consisting of epoxy resins and urethane resins, polishing holder according to any one of claims 1-3. The frame member does not include a glass fiber, abrasive holder according to any one of claims 1-4. A method of manufacturing the polishing holder according to any one of claims 1 to 5 , comprising:
A step of directly joining the frame member on the back pad,
A method for manufacturing a polishing holder. The frame material is formed of a photocurable resin,
The method of manufacturing a polishing holder according to claim 6 , wherein the forming step includes a step of screen-printing the photocurable resin. Said frame member is a filling material or a precursor of the frame member to the back arranged mold frame on the pad, it is formed by the curing of drying or the precursor of the material, according to claim 6 Of manufacturing a holder for polishing.

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