Synthetic grinding stone, synthetic grinding stone assembly, and method for manufacturing synthetic grinding stone

Abstract

A synthetic grinding stone for surface processing comprises abrasive grains, a binder made of a thermosetting resin material for maintaining the abrasive grains in a dispersed state, and a filler dispersed in the binder. The filler comprises at least one of a first filler having an average particle size larger than that of the abrasive grains, a second filler having conductivity, and a third filler harder than a workpiece.

Description

Technical Field

[0001] The present invention relates to a synthetic grindstone, a synthetic grindstone assembly, and a method for manufacturing the synthetic grindstone for use in surface processing such as chemical mechanical grinding (CMG). Background Art

[0002] Sometimes, a surface processing method based on dry chemical mechanical grinding (CMG) is used (for example, refer to Japanese Patent Gazette No. 4573492). In the CMG process, a synthetic grindstone to which an abrasive (abrasive grains) are fixed is used using a resin binder such as a thermoplastic resin. Then, while the wafer and the synthetic grindstone are rotated, the synthetic grindstone is pressed against the wafer (for example, refer to Japanese Patent Gazette No. 2004-87912). The convex parts on the wafer surface are heated / oxidized by friction with the synthetic grindstone, and thus become brittle and peel off. As a result, only the convex parts of the wafer are ground and flattened.

[0003] For synthetic grinding stones, for example, as the CMG process proceeds, abrasive grains (abrasives) gradually fall off from the surface of the synthetic grinding stone's binder (grinding action surface) relative to the object to be ground, and the grinding action surface of the synthetic grinding stone becomes smooth. Therefore, on the grinding action surface, for example, the contact opportunity between the thermoplastic resin-based binder and the object to be ground increases. As a result, the contact pressure between the abrasive grains and the object to be ground decreases, and the processing efficiency decreases. On the other hand, when dry processing is performed to increase the processing rate, the friction heat between the grinding action surface and the object to be ground becomes too large, and there is a possibility that the object to be ground will be burned or scratched due to the inclusion of grinding residues. Summary of the invention

[0004] An object of the present invention is to provide a synthetic grindstone, a synthetic grindstone assembly, and a method for manufacturing a synthetic grindstone that can suppress excessive frictional heat during dry grinding, for example.

[0005] A synthetic grinding stone for surface processing according to one embodiment of the present invention comprises: abrasive grains, a binder made of a thermosetting resin material that keeps the abrasive grains dispersed, and a filler that is dispersed in the binder. The filler comprises at least one of a first filler having an average particle size larger than that of the abrasive grains, a second filler having conductivity, and a third filler that is harder than the object to be ground. The abrasive grain rate (Vg) of the abrasive grains is greater than 0 volume % and less than 20 volume %, the binder rate (Vb) of the binder is greater than 5 volume % and less than 30 volume %, the first filler is greater than 0 volume % and less than 40 volume %, the second filler is greater than 0 volume % and less than 10 volume %, and the third filler is greater than 0 volume % and less than 20 volume %. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1Schematic diagram of the structure of the synthetic grindstone according to the embodiment.

[0007] Figure 2 It is a schematic diagram showing the production flow (production method) of a synthetic grindstone (molded body).

[0008] Figure 3 This is a table showing the volume ratios (abrasive grains, binder, filler) of synthetic grinding stones when producing synthetic grinding stones of the type using a thermosetting resin as a binder.

[0009] Figure 4 Schematic diagram showing a CMG device used for machining a workpiece.

[0010] Explanation of symbols

[0011] 10 ...CMG device, 43 ...grindstone holding member, 100 ...synthetic grindstone, 101 ...abrasive grains, 102 ...binder, 200 ...synthetic grindstone assembly. DETAILED DESCRIPTION

[0012] like Figure 1 As shown, the synthetic grindstone 100 is formed of abrasive grains (abrasive) 101 and a binder (adhesive) 102. The synthetic grindstone 100 may further have pores 103. In the present embodiment, the synthetic grindstone 100 is arranged such that the abrasive grains 101 are dispersed in the binder 102 and the pores 103 are dispersed in the binder 102.

[0013] The abrasive grains 101 are not limited to the following materials. When the object to be ground is silicon, for example, silicon dioxide, cerium oxide, or a mixture thereof can be appropriately applied. Similarly, when the object to be ground is sapphire, chromium oxide, iron oxide, or a mixture thereof can be appropriately applied. In addition, as abrasives that may be applied, aluminum oxide, silicon carbide, or a mixture thereof can also be used depending on the type of the object to be ground.

[0014] In this embodiment, the grinding object is silicon, and cerium oxide having an average particle size of about 1 μm is used as the abrasive grains 101. The particle size of the abrasive grains 101 can be appropriately set, and is preferably less than 5 μm, for example.

[0015] In this embodiment, a thermosetting resin is used as the binder 102. As an example of the thermosetting resin, a phenol resin can be used.

[0016] Synthetic grinding stone (molded body) 100 based on Figure 2 It is formed by the process (manufacturing method) shown.

[0017] First, make Figure 3Abrasive grains 101 and a liquid phenol serving as a binder 102 in a volume ratio described below are mixed to obtain a mixed material (step ST1 ).

[0018] Next, the mixed material is filled into a mold for forming the final shape of the synthetic grinding stone 100 (step ST2). For example, the synthetic grinding stone 100 is formed into a molded body by heat curing the liquid phenol at 190° C. for 30 minutes (step ST3). Then, the molded body in the mold is demolded (step ST4).

[0019] Figure 3 2 is a table showing the composition of the synthetic grinding stone 100 when the synthetic grinding stone 100 using a thermosetting resin as the binder 102 is produced as described above.

[0020] like Figure 3 As shown, the abrasive grain ratio (Vg) of the abrasive grains 101 is higher than 0 volume % and is 20 volume % or less. The binder ratio (Vb) of the binder 102 is 5 volume % or more and 30 volume % or less.

[0021] In the present embodiment, the synthetic grindstone 100 is formed into a ring shape and is used for dry chemical mechanical grinding (CMG) processing that performs processing by a mechanical action and a combined action based on chemical components. That is, the synthetic grindstone 100 performs a chemical mechanical grinding action on the surface of the wafer W as the object to be grinded in a dry manner, thereby performing surface processing of the wafer W as the object to be grinded. Then, the synthetic grindstone 100 is fixed to the grindstone holding member (base) 43 by double-sided tape, adhesive, etc., to form a synthetic grindstone assembly 200, which is mounted on Figure 4 The CMG device 10 shown is used for surface processing of a wafer W as a grinding object. The grindstone holding member 43 only needs to have appropriate rigidity to withstand CMG processing, have heat resistance at a temperature that can be increased by using the synthetic grindstone 100, and not be thermally softened, and for example, an aluminum alloy material or the like can be used.

[0022] The synthetic grindstone assembly 200 including the grindstone holding member 43 and the synthetic grindstone 100 and the wafer W as the object to be grinded are moved along the Figure 4 The wafer W is pressed against the synthetic grindstone 100 while rotating in the direction of the arrow in FIG. 1. At this time, the synthetic grindstone 100 is rotated at a peripheral speed of, for example, 600 m / min, and the processing pressure is 300 g / cm 2The wafer W is pressed. Therefore, the synthetic grindstone 100 slides on the surface of the wafer W. When the processing is started in this way, the synthetic grindstone 100 slides on the surface of the wafer W, and an external force acts on the binder 102. This external force acts continuously, and as the CMG process proceeds, the abrasive grains (abrasive) gradually fall off from the surface (grinding action surface) of the binder 102 of the synthetic grindstone 100 that faces the surface of the wafer W to be ground. Then, the surface of the wafer W is ground by the chemical mechanical action of the fixed abrasive grains 101 retained in the thermosetting resin as the binder 102 or the abrasive grains 101 that fall off from the thermosetting resin as the binder 102. The convex parts on the surface of the wafer W are heated / oxidized by the friction with the synthetic grindstone 100, and become brittle and peel off. As a result, only the convex parts on the surface of the wafer W are ground, and the surface of the wafer W is flattened.

[0023] In the present embodiment, a thermoplastic resin material (e.g., ethyl cellulose) is not used as a binder, but a thermosetting resin is used as the binder 102. Therefore, compared with the case where a thermoplastic resin material is used as a binder, the melting temperature can be increased, and the rigidity and mechanical strength of the synthetic grindstone 100 at a suitable high temperature can be stabilized. Therefore, compared with the case where a thermoplastic resin material is used as a binder, the synthetic grindstone 100 of the present embodiment can further increase the dimensional stability at a suitable high temperature. Therefore, for the synthetic grindstone 100 of the present embodiment, the deformation of the workpiece at a suitable high temperature during processing can be suppressed, and the shape accuracy can be improved.

[0024] When a thermoplastic resin material is used as a binder, when heat is accumulated between the synthetic grindstone and the wafer W, the thermoplastic resin material as a binder softens, and the surface of the synthetic grindstone is flattened. Furthermore, when the thermoplastic resin material as a binder melts and is welded to the surface of the wafer W in a process called sticking, the grinding resistance generated by the synthetic grindstone increases sharply, and the frictional heat becomes excessive, causing the surface of the wafer W to be roughened and scratched.

[0025] On the other hand, when a thermosetting resin is used as the binder 102 as in the synthetic grindstone 100 of the present embodiment, even if heat is stored in the binder 102, the melting point temperature of the binder 102 can be increased, and the flattening of the synthetic grindstone 100 at an appropriate temperature can be suppressed. Therefore, even if heat is stored between the synthetic grindstone and the wafer W, the resin can be prevented from melting. Therefore, the synthetic grindstone 100 of the present embodiment can maintain stable processing performance for a longer period of time. Therefore, it is possible to suppress the occurrence of accidental scratches on the surface of the wafer W as the object to be ground.

[0026] This is because the inventors of the present application, who have conducted intensive research to improve the excessive friction heat during dry grinding, have found that by forming the synthetic grinding stone 100 in a manner that satisfies the above-mentioned volume ratio, it is possible to achieve excellent workability on the object to be ground. That is, for example, the synthetic grinding stone 100 suitable for dry surface processing includes: abrasive grains 101 having an abrasive grain rate (Vg) greater than 0 volume % and less than 20 volume %, and a binder 102 made of a thermosetting resin material having a binder rate (Vb) of greater than 5 volume % and less than 30 volume %. It should be noted that the porosity (Vp) is set according to the values ​​of the abrasive grain rate (Vg) and the binder rate (Vb) so that the total is 100 volume %.

[0027] According to the present embodiment, it is possible to provide the synthetic grindstone 100 , the synthetic grindstone assembly 200 , and the method for manufacturing the synthetic grindstone 100 , which can suppress excessive frictional heat during dry grinding, for example.

[0028] In this embodiment, an example in which the synthetic grindstone 100 is provided in a disk shape is described. The synthetic grindstone 100 may be formed in various shapes such as a granular shape or an elongated rectangular parallelepiped shape. The synthetic grindstone assembly 200 may be formed in an appropriate shape so as to hold the synthetic grindstone 100 .

[0029] It should be noted that the synthetic grindstone 100 described in this embodiment uses a thermosetting resin material as a binder 102. Generally speaking, it has greater rigidity than a synthetic grindstone using a thermoplastic resin material as a binder, and has lower rigidity than a synthetic grindstone using a vitrified material as a binder. Therefore, in order to match the raw material of the object to be grinded, the best grindstone can be selected from the synthetic grindstone 100 using a thermosetting resin material as a binder 102, the synthetic grindstone using an existing thermoplastic resin material as a binder, and the synthetic grindstone using an existing vitrified material as a binder. That is, the synthetic grindstone 100 of this embodiment can broaden the range of choices for the object to be grinded. For example, there is a need for a user to use a synthetic grindstone that has greater rigidity than a synthetic grindstone using a thermoplastic resin material as a binder and less rigidity than a synthetic grindstone using a vitrified material as a binder. By using the synthetic grindstone 100 of this embodiment, such a need can be met.

[0030] Although the synthetic grindstone 100 of the present embodiment is described as an example in which dry machining is used, the synthetic grindstone 100 may be used for wet machining using grinding water (for example, pure water), for example.

[0031] In the present embodiment, an example of using phenolic resin as a thermosetting resin material for the binder 102 is described. As the thermosetting resin material for the binder 102, for example, epoxy resin, melamine resin, hard urethane resin, urea resin, unsaturated polyester resin, alkyd resin, polyimide resin, polyvinyl acetal resin, etc. can be used. These resin materials can also be used in appropriate combination. The cured product formed by curing these thermosetting resin materials has excellent water resistance, chemical resistance, and heat resistance, and has moderate hardness, and excellent shape stability and dimensional stability during use.

[0032] (First Modification)

[0033] A case where the synthetic grindstone 100 according to the present modification includes coarse particles of an appropriate size as the first filler will be described.

[0034] The first filler is preferably spherical, for example, but is not necessarily limited to a sphere, and may be block-shaped and may include a small amount of concavo-convex or deformation. The first filler is, for example, silica, which is dispersed and fixed by a binder 102 made of a thermosetting resin material. The first filler preferably includes silica having a larger particle size than the particle size of the abrasive grains 101, and silica having a smaller particle size fixed around the silica having a larger particle size. The silica having a smaller particle size is preferably smaller than the particle size of the abrasive grains 101. The volume ratio of the first filler in the synthetic grindstone 100 can be set, for example, based on the binder ratio (Vb) of the binder 102 and according to the correlation with the abrasive ratio (Vg) of the abrasive grains 101. The first filler is preferably more than 0 volume % and less than 40 volume %.

[0035] It should be noted that the abrasive grains 101 made of cerium oxide are as soft as or equal to the wafer W or its oxide relative to the silicon workpiece W. In addition, the first filler made of silicon dioxide is as soft as or equal to the wafer W or its oxide relative to the abrasive grains 101.

[0036] The synthetic grindstone 100 including the abrasive grains 101 , the binder 102 made of a thermosetting resin material, and the first filler is manufactured as described in the above embodiment.

[0037] The average particle size of the first filler is larger than that of the abrasive grains 101, so the synthetic grindstone 100 and the wafer W being processed are in contact with each other substantially through the apex of the first filler. That is, between the base material (abrasive grains 101 and the binder 102 made of a thermosetting resin material) of the synthetic grindstone 100 and the wafer W, the base material and the wafer W are not in direct contact due to the presence of the first filler, and a certain gap is formed.

[0038] When the processing starts in the state where the first filler is in contact with the wafer W, an external force acts on the base material. The abrasive grains 101 fall off from the base material due to the continuous action of the external force. The free abrasive grains 101 are present at the processing interface in the gap between the synthetic grindstone 100 and the wafer W in the state of being attached to the first filler. Therefore, the abrasive grains 101 being processed and the wafer W are basically in contact through the apex of the first filler. Therefore, the actual contact area between the abrasive grains 101 and the wafer W is greatly reduced, and the acting pressure at the processing point is increased. Therefore, grinding processing can be performed with high processing efficiency.

[0039] The gap promotes the circulation between the surface of the wafer W and the outside atmosphere, and the processed surface is cooled. In addition, the residue generated by the abrasive grains 101 is discharged from the wafer W to the outside through the gap, and the surface of the wafer W can be prevented from being damaged. As a result, the surface of the wafer W can be prevented from being burned or scratched due to frictional heat.

[0040] Thus, the synthetic grindstone 100 can grind the surface of the wafer W to be flat and have a predetermined surface roughness.

[0041] According to the synthetic grindstone 100 of this modification, even when machining is performed, the contact pressure between the abrasive grains 101 and the wafer W can be sufficiently maintained to maintain machining efficiency, and by suppressing direct contact between the adhesive 102 and the wafer W, the quality of the wafer W can be prevented from being degraded and scratches from being generated. In this modification, as described in the above-mentioned embodiment, it is possible to suppress the frictional heat generated between the synthetic grindstone 100 and the workpiece from becoming excessive.

[0042] As the first filler, silica, carbon, and silica gel as porous bodies thereof, activated carbon, spherical resin, etc. It should be noted that hollow spheres used as pore-forming agents are not suitable because they may break during processing and cause scratches.

[0043] (Second Modification)

[0044] The synthetic grindstone 100 of this modification includes a conductive material as a second filler that is smaller than the first filler described in the first modification and has an appropriate size. In addition, in this modification, an example is described in which the grindstone holding member 43 of the CMG device 10 described above uses, for example, an aluminum alloy material as a raw material having electrical conductivity and appropriate thermal conductivity.

[0045] As the conductive material, carbon nanotubes and the like can be cited. These materials have a smaller average particle size than the abrasive grains 101. The volume ratio of the second filler in the synthetic grindstone 100 can be set, for example, based on the binder ratio (Vb) of the binder 102 and in accordance with the correlation with the abrasive ratio (Vg) of the abrasive grains 101. The second filler is preferably added in a range of more than 0 volume % and within 10 volume %.

[0046] In addition, the second filler can improve the strength of the structure of the synthetic grindstone 100 by using, for example, carbon nanotubes.

[0047] When the CMG device 10 starts processing the wafer W, the synthetic grindstone 100 and the wafer W slide, and an external force is applied to the adhesive 102. As the external force continues to act, the abrasive grains 101 fall off onto the wafer W. The free abrasive grains 101 slide in the gap between the synthetic grindstone 100 and the wafer W. The surface of the wafer W is polished by the chemical mechanical action of the abrasive grains 101.

[0048] When the surface of the wafer W is polished and rubbed, static electricity is generated on the surface of the wafer W. At this time, the conductive second filler causes the static electricity on the surface of the wafer W to flow to the grindstone holding member 43 (see Figure 4 ). Therefore, by using the synthetic grindstone 100 of this modification, static electricity generated on the surface of the wafer W can be removed while grinding the surface of the wafer W. As a result, dust and the like can be prevented from being attached to the surface of the wafer W.

[0049] In addition, in this modification, the thermal conductivity of the grindstone holding member 43 is higher than that of the synthetic grindstone 100. When the surface of the wafer W is ground and friction occurs, friction heat is generated on the surface of the wafer W. At this time, the friction heat is absorbed by the second filler, and the heat absorbed by the second filler is transferred to the grindstone holding member 43. Therefore, by using the synthetic grindstone 100 of this modification, the surface of the wafer W can be ground while the friction heat generated on the surface of the wafer W is removed. As a result, it is possible to prevent the surface of the wafer W from being burned due to the friction heat between the surface of the synthetic grindstone 100 and the surface of the wafer W, and also to prevent scratches. Therefore, the synthetic grindstone 100 of this modification can not only process the surface of the wafer W well, but also extend the life of the synthetic grindstone 100.

[0050] It should be noted that it is also preferable to provide a heat dissipation portion such as a heat sink on the grindstone holding member 43 that rotates together with the synthetic grindstone 100, that is, it is preferable that the synthetic grindstone assembly 200 has a heat dissipation portion (heat transfer portion). In this case, the heat dissipation portion contacts the air by rotating, and the heat of the synthetic grindstone 100 can be effectively dissipated.

[0051] Furthermore, by providing a water distribution pipe for cooling water or the like inside the grindstone holding member 43 , the grindstone holding member 43 and the synthetic grindstone 100 can also be cooled.

[0052] In this modification, the example in which the grindstone holding member 43 has electrical conductivity and higher thermal conductivity than the synthetic grindstone 100 has been described, but it may be formed of a material having at least one of electrical conductivity and higher thermal conductivity than the synthetic grindstone 100. When it has electrical conductivity, static electricity between the grinded object and the synthetic grindstone 100 can be removed, and when it has higher thermal conductivity than the synthetic grindstone 100, heat generated in the synthetic grindstone 100 can be effectively dissipated.

[0053] It should be noted that, in the first modification, an example of using the first filler is described, and in the second modification, an example of using the second filler is described. The synthetic grindstone 100 also preferably includes both the first filler and the second filler. In this case, the abrasive grain rate of the abrasive grains 101 is, for example, 2.5% by volume, the binder rate of the binder 102 is, for example, 22% by volume, the porosity of the pores 103 is, for example, 48%, the first filler is 25% by volume, and the second filler is 2.5% by volume. In this case as well, for the synthetic grindstone 100, the binder rate (Vb) of the binder 102 is first determined, and then the abrasive grain rate (Vb) of the abrasive grains 101 and the volume ratio of the first filler and the second filler are set based on the correlation among the abrasive grains 101, the first filler, and the second filler.

[0054] (Third Modification)

[0055] A case where the synthetic grindstone 100 of the present modification includes particles smaller than the first filler described in the first modification and having an appropriate size as the third filler will be described.

[0056] As the particles of the third filler, green carborundum (GC) and the like can be cited. These particles are harder than the wafer W as the object to be ground. The particles of the third filler such as GC can be larger or smaller than the average particle size of the abrasive grains 101. Of course, the particles of GC and the like can also be of the same size as the average particle size of the abrasive grains 101.

[0057] For example, the average particle size of the abrasive grains 101 of metal oxides such as alumina, zirconia, ceria, and silica can be larger than GC, smaller than GC, or the same as GC. For example, the average particle size of the abrasive grains 101 of alumina, zirconia, and ceria is basically larger than GC. For example, the average particle size of the abrasive grains 101 of alumina can be the same as GC (~200nm). For example, when the particles of GC and the like are 10nm, the average particle size of the abrasive grains 101 of silica and the like can be 1nm.

[0058] The volume ratio of the third filler in the synthetic grindstone 100 can be set based on the binder ratio (Vb) of the binder 102 and the correlation with the abrasive ratio (Vg) of the abrasive grains 101. The third filler is preferably added in a range of more than 0 volume % and within 20 volume %.

[0059] There is a technique for forming gettering sites such as fine scratches on the back side of the wafer W opposite to the surface and capturing impurities through the gettering sites (gettering effect). GC is harder than the back side of the wafer W and is used to intentionally form scratches on the back side of the wafer W.

[0060] In this modification, as described in the above embodiment, excessive frictional heat due to heat generated between the synthetic grindstone 100 and the object to be grinded can be suppressed. In addition, if the GC has conductivity, static electricity generated between the synthetic grindstone 100 and the object to be grinded can be suppressed.

[0061] It should be noted that the example of using the first filler is described in the first modification, and the example of using the second filler is described in the second modification. It is also preferable that the synthetic grindstone 100 includes two or three of the first filler, the second filler, and the third filler. In the case of including the three, it is preferable that the abrasive grain rate of the abrasive grains 101 is, for example, greater than 0 volume % and less than 20 volume %, the binder rate is 5 volume % or more and less than 30 volume %, the first filler is greater than 0 volume % and less than 40 volume %, the second filler is greater than 0 volume % and less than 10 volume %, and the third filler is greater than 0 volume % and less than 10 volume %. The total of the second filler and the third filler is preferably greater than 0 volume % and less than 20 volume %. In the case where the synthetic grindstone 100 includes the second filler and the third filler, the second filler is preferably less than 10 volume %.

[0062] It should be noted that the present invention is not limited to the above-mentioned embodiments, and various modifications can be made in the implementation stage without departing from the scope of the main purpose. In addition, each embodiment can also be implemented in appropriate combination, and in such a case, the effect of the combination can be obtained. In addition, the above-mentioned embodiments include various inventions, and various inventions can be extracted from the combination of multiple constituent elements selected from the disclosure. For example, in the case where the technical problem can be solved and the effect can be obtained even if some constituent elements are deleted from all the constituent elements shown in the embodiment, the structure in which the constituent elements are deleted can be extracted as an invention.

Claims

1. A synthetic grinding stone for surface processing, the synthetic grinding stone having: Abrasive particles, a binder made of a thermosetting resin material for maintaining the abrasive grains in a dispersed state, and a filler dispersed in the binder, the filler comprising a first filler having an average particle size larger than the abrasive grains and a second filler having conductivity, or the filler comprising a first filler having an average particle size larger than the abrasive grains and a third filler harder than the object to be ground, The abrasive grain ratio (Vg) of the abrasive grains is greater than 0 volume % and less than 20 volume %, The binder ratio (Vb) of the binder is 5 volume % or more and 30 volume % or less, The first filler is greater than 0 volume % and less than 40 volume %, The second filler is 0 volume % or more and 10 volume % or less, The third filler is greater than or equal to 0 volume % and less than or equal to 20 volume %.

2. A synthetic grinding stone for surface processing, the synthetic grinding stone having: Abrasive particles, a binder made of a thermosetting resin material for maintaining the abrasive grains in a dispersed state, and Carbon nanotubes as a filler having electrical conductivity are dispersed in the binder, When the synthetic grindstone is held by a conductive grindstone holding member, the carbon nanotubes allow static electricity generated on the surface of the workpiece due to grinding to flow to the grindstone holding member, thereby grinding the surface of the workpiece while removing static electricity generated on the surface of the workpiece.

3. The synthetic grindstone according to claim 2, wherein: The abrasive grain ratio (Vg) of the abrasive grains is greater than 0 volume % and less than 20 volume %, The binder ratio (Vb) of the binder is 5 volume % or more and 30 volume % or less, The carbon nanotubes are present in an amount of 0 volume % or more and 10 volume % or less.

4. A synthetic grinding stone assembly comprising: The synthetic grinding stone according to any one of claims 1 to 3, and A base body is provided to fix the synthetic grinding stone and has at least one of electrical conductivity and thermal conductivity higher than that of the synthetic grinding stone.

5. A method for manufacturing a synthetic grinding stone as claimed in claim 1, the method comprising: mixing the abrasive grains, the binder and the filler to obtain a mixed material; Filling the mixed material into a mold and molding it by hot pressing; as well as Demolding the molded body after molding, The abrasive rate (Vg) of the abrasive is set to be greater than 0 volume % and less than 20 volume %, the binder rate (Vb) of the binder is set to be greater than 5 volume % and less than 30 volume %, the first filler is set to be greater than 0 volume % and less than 40 volume %, the second filler is set to be greater than 0 volume % and less than 10 volume %, and the third filler is set to be greater than 0 volume % and less than 20 volume %.

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