Resin sheet for semiconductor manufacturing process

Abstract

Provided is a resin sheet for a semiconductor manufacturing process, comprising a cycloolefin resin having a glass transition temperature of 115°C or higher.

Description

Resin sheets for semiconductor manufacturing processes

[0001] The present invention relates to a resin sheet for use in semiconductor manufacturing processes, and more particularly to a resin sheet for use in semiconductor manufacturing processes that has excellent acid resistance, alkali resistance, abrasion resistance, and cutting workability, and in which the elution of metal ions is effectively suppressed.

[0002] The semiconductor manufacturing process consists of many steps, such as mask manufacturing, wafer manufacturing, thin film formation, photoresist coating, exposure and development, etching, resist stripping and cleaning, ion implantation, electrode formation, and inspection.

[0003] Among these semiconductor manufacturing processes, in the wafer manufacturing process, various resin materials are used for polishing pads, polishing frames, wafer storage cases, etc. Resins used in the wafer manufacturing process are required to have excellent properties such as acid resistance, alkali resistance, and abrasion resistance.

[0004] For example, in wafer manufacturing processes, glass epoxy resins are used as resins for polishing pads (see, for example, Patent Document 1). However, glass epoxy resins have problems such as insufficient acid resistance and alkali resistance, and are prone to elution of metal ions, which can contaminate wafers.

[0005] JP 2009-208199 A

[0006] The present invention has been made in view of the above circumstances, and aims to provide a resin sheet for semiconductor manufacturing processes that has excellent acid resistance, alkali resistance, abrasion resistance, and cutting workability, and in which the elution of metal ions is effectively suppressed.

[0007] The present inventors have conducted studies to achieve the above object and have found that the above problems can be solved by using a cycloolefin resin having a glass transition temperature of 115°C or higher, thereby completing the present invention.

[0008] That is, according to the present invention, there are provided the following resin sheet for semiconductor manufacturing processes, a polishing frame, a frame for wafer-holding pads, a method for manufacturing a resin sheet for semiconductor manufacturing processes, and use of a resin sheet for semiconductor manufacturing processes in a semiconductor manufacturing process. [1] A resin sheet for semiconductor manufacturing processes containing a cycloolefin-based resin having a glass transition temperature of 115°C or higher. [2] The resin sheet for semiconductor manufacturing processes according to [1], which has a surface roughness (Ra) of 0.1 μm or less. [3] The resin sheet for semiconductor manufacturing processes according to [1] or [2], wherein the cycloolefin-based resin is obtained by thermally curing a cycloolefin monomer. [4] The resin sheet for semiconductor manufacturing processes according to [3], wherein the cycloolefin-based resin is obtained by thermally curing a monomer mixture liquid containing dicyclopentadiene and / or tricyclopentadiene. [5] A polishing frame made from the resin sheet for semiconductor manufacturing processes according to any one of [1] to [4]. [6] A frame for wafer-holding pads made from the resin sheet for semiconductor manufacturing processes according to any one of [1] to [4]. [7] A method for producing a resin sheet for use in semiconductor manufacturing processes according to any one of [1] to [4], comprising the steps of filling a mold having a cavity with a thickness of 0.5 to 3.0 mm with a cycloolefin monomer, and thermally curing the cycloolefin monomer in the mold. [8] A method for producing a resin sheet for use in semiconductor manufacturing processes according to [7], further comprising, after the thermal curing step, a secondary thermal curing of the heat-cured product at a temperature higher than the thermal curing temperature in the thermal curing step. [9] A method for producing a resin sheet for use in semiconductor manufacturing processes according to [8], wherein the heating temperature in the secondary thermal curing step is 200 to 260°C.

[10] A method for producing a resin sheet for use in semiconductor manufacturing processes according to any one of [1] to [4], comprising the steps of obtaining a cycloolefin resin block, slicing the cycloolefin resin block to obtain a sheet of cycloolefin resin, and polishing the sheet of cycloolefin resin.

[11] A method for producing a resin sheet for a semiconductor manufacturing process according to any one of [1] to [4], comprising the steps of: plasticizing a thermoplastic cycloolefin resin; and extruding the plasticized cycloolefin resin into a sheet shape and then cooling it to form a sheet having a thickness of 0.5 to 3 mm.

[12] Use of the resin sheet for a semiconductor manufacturing process according to any one of [1] to [4] in a semiconductor manufacturing process.

[0009] According to the present invention, it is possible to provide a resin sheet for use in semiconductor manufacturing processes that has excellent acid resistance, alkali resistance, abrasion resistance and cutting workability, and in which the elution of metal ions is effectively suppressed.

[0010] The resin sheet for semiconductor manufacturing processes of the present invention is a resin sheet used in semiconductor manufacturing processes, and contains a cycloolefin resin having a glass transition temperature of 115° C. or higher.

[0011] The resin sheet for semiconductor manufacturing process of the present invention is not particularly limited as long as it is a resin sheet used in the semiconductor manufacturing process, but may be used in any process such as mask manufacturing process, wafer manufacturing process, thin film formation, photoresist coating, exposure / development, etching, resist stripping / cleaning, ion implantation, electrode formation, and inspection. However, the resin sheet for semiconductor manufacturing process of the present invention has excellent acid resistance, alkali resistance, abrasion resistance, and cutting workability, and effectively suppresses the elution of metal ions, so it can be suitably used in the wafer manufacturing process. More specifically, in the wafer manufacturing process, it can be suitably used for polishing pads, polishing frames (for example, frames for wafer holding pads for holding wafers during polishing), wafer storage cases, etc.

[0012] In particular, the present inventors have conducted extensive research and have found that by using a cycloolefin resin having a glass transition temperature of 115°C or higher as a resin sheet for semiconductor manufacturing processes, it is possible to obtain a resin sheet having excellent acid resistance, alkali resistance, abrasion resistance, and cutting workability, and in which the elution of metal ions is effectively suppressed, thereby completing the present invention.

[0013] The resin sheet for semiconductor manufacturing processes of the present invention contains a cycloolefin resin (hereinafter simply referred to as "cycloolefin resin") having a glass transition temperature of 115°C or higher. The glass transition temperature of the cycloolefin resin may be 115°C or higher, but is preferably 120°C or higher, more preferably 130°C or higher, and even more preferably 140°C or higher. The upper limit of the glass transition temperature of the cycloolefin resin is not particularly limited, but is preferably 250°C or lower, more preferably 245°C or lower. If the glass transition temperature is too low, the resin will have poor machinability, and as a result, when applied to semiconductor manufacturing processes and processed into a desired shape depending on the application, the accuracy of the shape obtained will be reduced.

[0014] The resin sheet for semiconductor manufacturing process of the present invention may be in a sheet form, and its thickness is not particularly limited and may be set depending on the process to be applied, but is preferably 0.5 to 3.0 mm, more preferably 0.7 to 2.5 mm, and even more preferably 1.0 to 2.0 mm.

[0015] Furthermore, from the viewpoint of being able to provide the resin sheet for semiconductor manufacturing process of the present invention with superior acid resistance and alkali resistance, the surface roughness (Ra) is preferably 0.1 μm or less, more preferably 0.05 μm or less, and even more preferably 0.01 μm or less. The lower limit of the surface roughness (Ra) is not particularly limited, but is preferably 0.0001 μm or more. The surface roughness (Ra) can be measured by measuring the resin sheet for semiconductor manufacturing process using a white light interferometer.

[0016] The resin sheet for semiconductor manufacturing process of the present invention may contain a cycloolefin resin, preferably a cycloolefin resin in a proportion of 90% by weight or more, more preferably a cycloolefin resin in a proportion of 95% by weight or more, and even more preferably a cycloolefin resin in a proportion of 99% by weight or more, and particularly preferably a resin sheet consisting essentially of a cycloolefin resin, i.e., a resin sheet consisting essentially of only a cycloolefin resin and components used in the production of the cycloolefin resin (for example, a polymerization catalyst, an antioxidant, etc.).

[0017] The cycloolefin resin may be either a thermosetting cycloolefin resin or a thermoplastic cycloolefin resin.

[0018] [Thermosetting cycloolefin-based resin] The thermosetting cycloolefin-based resin is obtained by thermally curing a cycloolefin monomer, and among these, preferred is one obtained by bulk polymerization of a cycloolefin monomer in the presence of a metathesis polymerization catalyst.

[0019] A cycloolefin monomer is a compound having an alicyclic structure and a carbon-carbon double bond in the molecule. Examples of the alicyclic structure constituting the cycloolefin monomer include a monocyclic ring, a polycyclic ring, a fused polycyclic ring, a bridged ring, and a polycyclic ring formed by combining these rings. There is no particular limitation on the number of carbon atoms constituting the alicyclic structure, but it is preferably 4 to 30, more preferably 5 to 20, and even more preferably 5 to 15.

[0020] Examples of cycloolefin monomers include monocyclic cycloolefin monomers and norbornene-based monomers, and among these, norbornene-based monomers are preferred. Norbornene-based monomers are cycloolefin monomers having a norbornene ring structure in the molecule. These may be substituted with a hydrocarbon group such as an alkyl group, an alkenyl group, an alkylidene group, or an aryl group, or a polar group. Furthermore, the norbornene-based monomer may have a double bond in addition to the double bond of the norbornene ring.

[0021] Examples of the monocyclic cycloolefin monomer include cyclobutene, cyclopentene, cyclooctene, cyclododecene, cyclopentadiene, and 1,5-cyclooctadiene.

[0022] Specific examples of norbornene-based monomers include dicyclopentadiene (tricyclo[4.3.0.1] ２，５ ]deca-3,7-diene), methyldicyclopentadiene, dicyclopentadiene monoepoxide, and other dicyclopentadienes; tetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodec-4-ene, 9-ethylidenetetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodec-4-ene, 9-phenyltetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodec-4-ene, tetracyclo[6.2.1.1 ３，６ .0 ２，７ ] dodec-9-ene-4-carboxylic acid, tetracyclo[6.2.1.1 ３，６ .0 ２，７ ] tetracyclododecenes such as dodec-9-ene-4,5-dicarboxylic anhydride; norbornenes such as 2-norbornene, 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene, 5-phenyl-2-norbornene, 5-norbornen-2-yl acrylate, 5-norbornen-2-yl methacrylate, 5-norbornene-2-carboxylic acid, 5-norbornene-2,3-dicarboxylic acid, and 5-norbornene-2,3-dicarboxylic anhydride; oxanorbornenes such as 7-oxa-2-norbornene and 5-ethylidene-7-oxa-2-norbornene; tetracyclo[9.2.1.0 ２，１０ .0 ３，８ ]tetradeca-3,5,7,12-tetraene (also known as 1,4-methano-1,4,4a,9a-tetrahydro-9H-fluorene), pentacyclo[6.5.1.1 ３，６ .0 ２，７ .0 ９，１３ ] pentadeca-4,10-diene, pentacyclo[9.2.1.0 ２，１０ .0３，８ ] tetracyclic or higher ring olefins such as pentadeca-5,12-diene and tricyclopentadiene; and the like.

[0023] Among these cycloolefin monomers, it is preferable to contain a cycloolefin monomer having no polar group, since this can further improve the acid resistance and alkali resistance.

[0024] These cycloolefin monomers may be used alone or in combination of two or more thereof. Any monomer copolymerizable with the cycloolefin monomer may also be used.

[0025] The content of the norbornene-based monomer in the cycloolefin monomer is preferably 50 to 100% by weight, more preferably 70 to 100% by weight, even more preferably 90 to 100% by weight, and particularly preferably 100% by weight.

[0026] The metathesis polymerization catalyst is not particularly limited as long as it can ring-opening polymerize a cycloolefin monomer, and known metathesis polymerization catalysts can be used.

[0027] A metathesis polymerization catalyst is a complex formed by bonding a plurality of ions, atoms, polyatomic ions, and / or compounds to a transition metal atom as a central atom. The transition metal atom is an atom of Groups 5, 6, or 8 (long-form periodic table, the same applies hereinafter). The atoms of each group are not particularly limited. Examples of Group 5 atoms include tantalum, Group 6 atoms include molybdenum and tungsten, and Group 8 atoms include ruthenium and osmium. Among these transition metal atoms, Group 8 atoms such as ruthenium and osmium are preferred. That is, the metathesis polymerization catalyst used in the present invention is preferably a complex having ruthenium or osmium as the central atom, and more preferably a complex having ruthenium as the central atom. A ruthenium-carbene complex in which a carbene compound is coordinated to ruthenium is preferred as a complex having ruthenium as the central atom. Here, "carbene compound" is a general term for compounds having a methylene free radical, and refers to a compound having an uncharged divalent carbon atom (carbene carbon) represented by (>C:). Ruthenium carbene complexes have excellent catalytic activity during bulk ring-opening polymerization, so the resulting polymer has little odor due to unreacted monomers, and high-quality polymers can be obtained with good productivity. In addition, they are relatively stable against oxygen and moisture in the air and are not easily deactivated, so they can be used in the atmosphere. The metathesis polymerization catalyst may be used alone or in combination of multiple types.

[0028] Examples of the ruthenium carbene complex include those represented by the following general formula (1) or (2).

[0029] In the above general formulas (1) and (2), R １ and R ２ are each independently a hydrogen atom; a halogen atom; or an organic group having 1 to 20 carbon atoms which may contain a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, or a silicon atom; and these groups may have a substituent, and may be bonded to each other to form a ring. １ and R ２Examples of groups bonded to each other to form a ring include an indenylidene group which may have a substituent, such as a phenylindenylidene group.

[0030] Specific examples of the organic group having 1 to 20 carbon atoms which may contain a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom or a silicon atom include an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkenyloxy group having 2 to 20 carbon atoms, an alkynyloxy group having 2 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, an aryloxy group having 1 to 8 carbon atoms, an alkyl group having 1 to 20 carbon atoms, an alkyl group having 2 to 20 carbon atoms, an alkynyloxy group having 2 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, an alkyl group having 1 to 8 ... alkyl group having 2 to 20 carbon atoms, an alkyl group having 2 to 20 carbon atoms, an alkyl group having 2 to 20 carbon atoms, an alkyl group having 2 to 20 carbon atoms, an alkyl group having 2 to 20 carbon atoms, an alkyl group having 2 to Examples of the organic group include alkylthio groups, carbonyloxy groups, alkoxycarbonyl groups having 1 to 20 carbon atoms, alkylsulfonyl groups having 1 to 20 carbon atoms, alkylsulfinyl groups having 1 to 20 carbon atoms, alkylsulfonic acid groups having 1 to 20 carbon atoms, arylsulfonic acid groups having 6 to 20 carbon atoms, phosphonic acid groups, arylphosphonic acid groups having 6 to 20 carbon atoms, alkylammonium groups having 1 to 20 carbon atoms, and arylammonium groups having 6 to 20 carbon atoms. These organic groups having 1 to 20 carbon atoms, which may contain a halogen atom, oxygen atom, nitrogen atom, sulfur atom, phosphorus atom, or silicon atom, may have a substituent. Examples of the substituent include alkyl groups having 1 to 10 carbon atoms, alkoxy groups having 1 to 10 carbon atoms, and aryl groups having 6 to 10 carbon atoms.

[0031] X １ and X ２ each independently represents an anionic ligand. The anionic ligand is a ligand that has a negative charge when separated from the central metal atom, and examples thereof include a halogen atom, a diketonate group, a substituted cyclopentadienyl group, an alkoxyl group, an aryloxy group, and a carboxyl group.

[0032] L １ and L ２represents a heteroatom-containing carbene compound or a neutral electron donor compound other than a heteroatom-containing carbene compound. Heteroatom-containing carbene compounds and neutral electron donor compounds other than a heteroatom-containing carbene compound are compounds that have a neutral charge when separated from a central metal. From the viewpoint of improving catalytic activity, heteroatom-containing carbene compounds are preferred. The heteroatom refers to an atom of Groups 15 and 16 of the periodic table, and specific examples include a nitrogen atom, an oxygen atom, a phosphorus atom, a sulfur atom, an arsenic atom, and a selenium atom. Among these, from the viewpoint of obtaining a stable carbene compound, a nitrogen atom, an oxygen atom, a phosphorus atom, and a sulfur atom are preferred, and a nitrogen atom is more preferred.

[0033] The heteroatom-containing carbene compound is preferably a compound represented by the following general formula (3) or (4), and from the viewpoint of improving catalytic activity, a compound represented by the following general formula (3) is more preferred.

[0034] In the above general formulas (3) and (4), R ３ , R ４ , R ５ and R ６ each independently represents a hydrogen atom; a halogen atom; or an organic group having 1 to 20 carbon atoms which may contain a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, or a silicon atom. Specific examples of the organic group having 1 to 20 carbon atoms which may contain a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, or a silicon atom are the same as those in the general formulas (1) and (2) above. ３ , R ４ , R ５ and R ６ may be bonded to each other in any combination to form a ring.

[0035] In addition, since the effect of the present invention becomes more remarkable, R ５ and R ６ is preferably a hydrogen atom. ３ and R ４is preferably an aryl group which may have a substituent, more preferably a phenyl group having an alkyl group of 1 to 10 carbon atoms as a substituent, and even more preferably a mesityl group.

[0036] Examples of the neutral electron donor compound include oxygen atoms, water, carbonyls, ethers, nitriles, esters, phosphines, phosphinites, phosphites, sulfoxides, thioethers, amides, imines, aromatic compounds, cyclic diolefins, olefins, isocyanides, and thiocyanates.

[0037] In the above general formulas (1) and (2), R １ , R ２ , X １ , X ２ , L １ and L ２ may be linked together in any combination to form a multidentate chelating ligand.

[0038] Furthermore, as the ruthenium carbene complex, among the compounds represented by the above general formula (1) or (2), the compound represented by the above general formula (1) is preferred in that the effects of the present invention are more pronounced, and among these, the compound represented by the following general formula (5) or general formula (6) is more preferred.

[0039] General formula (5) is shown below.

[0040] In the general formula (5), Z is an oxygen atom, a sulfur atom, a selenium atom, or NR １２ , P.R. １２ or AsR １２ and R １２ represents a hydrogen atom; a halogen atom; or an organic group having 1 to 20 carbon atoms which may contain a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, or a silicon atom; however, an oxygen atom is preferred as Z because the effects of the present invention will be more pronounced.

[0041] In addition, R １ , R ２ , X １ and L １are the same as those in the above general formulas (1) and (2), and may be bonded to each other alone or in any combination to form a multidentate chelating ligand, but X １ and L １ does not form a multidentate chelating ligand, and R １ and R ２ are preferably bonded to each other to form a ring, are more preferably an indenylidene group which may have a substituent, and are even more preferably a phenylindenylidene group. Specific examples of the organic group having 1 to 20 carbon atoms which may contain a halogen atom, oxygen atom, nitrogen atom, sulfur atom, phosphorus atom, or silicon atom are the same as those in the general formulae (1) and (2) above.

[0042] In the above general formula (5), R ７ and R ８ are each independently a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or a heteroaryl group having 6 to 20 carbon atoms, and these groups may have a substituent or may be bonded to each other to form a ring. Examples of the substituent include an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an aryl group having 6 to 10 carbon atoms, and when a ring is formed, the ring may be any of an aromatic ring, an alicyclic ring, and a heterocyclic ring, but it is preferable to form an aromatic ring, more preferably an aromatic ring having 6 to 20 carbon atoms, and even more preferably an aromatic ring having 6 to 10 carbon atoms.

[0043] In the above general formula (5), R ９ , R １０ and R １１ are each independently a hydrogen atom; a halogen atom; or an organic group having 1 to 20 carbon atoms which may contain a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, or a silicon atom; and these groups may have a substituent or may be bonded to each other to form a ring. Specific examples of the organic group having 1 to 20 carbon atoms which may contain a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, or a silicon atom are the same as those in the general formulas (1) and (2) above. R ９ , R１０ and R １１ is preferably a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, and more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

[0044] Specific examples of the compound represented by the general formula (5) and the production method thereof are described in, for example, WO 03 / 062253 (JP 2005-515260 A).

[0045] General formula (6) is shown below.

[0046] In the above general formula (6), m is 0 or 1. m is preferably 1, in which case Q is an oxygen atom, a nitrogen atom, a sulfur atom, a methylene group, an ethylene group or a carbonyl group, and preferably a methylene group.

[0047] In the above general formula (6), is a single bond or a double bond, preferably a single bond.

[0048] R １ , X １ , X ２ and L １ are the same as those in the above general formulas (1) and (2), and may be bonded to each other alone or in any combination to form a multidentate chelating ligand, but X １ , X ２ and L １ does not form a multidentate chelating ligand, and R １ is preferably a hydrogen atom.

[0049] R １３ ~R ２１ is a hydrogen atom; a halogen atom; or an organic group having 1 to 20 carbon atoms which may contain a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, or a silicon atom; and these groups may have a substituent or may be bonded to each other to form a ring. Specific examples of the organic group having 1 to 20 carbon atoms which may contain a halogen atom, an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, or a silicon atom are the same as those in the general formulas (1) and (2) above. R１３ is preferably an alkyl group having 1 to 20 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and R １４ ~R １７ is preferably a hydrogen atom, and R １８ ~R ２１ is preferably a hydrogen atom or a halogen atom.

[0050] Specific examples of the compound represented by the general formula (6) and methods for producing the same are described in, for example, WO 11 / 079799 (JP 2013-516392 A).

[0051] The content of the metathesis polymerization catalyst is preferably 0.005 mmol or more, more preferably 0.01 to 50 mmol, and even more preferably 0.015 to 20 mmol, per mole of the total cycloolefin monomers used in the reaction.

[0052] Furthermore, when a ruthenium carbene complex is used as the metathesis polymerization catalyst, a Lewis base compound can be used as the activity regulator. Examples of the Lewis base compound include Lewis base compounds containing a phosphorus atom, such as tricyclopentylphosphine, tricyclohexylphosphine, triphenylphosphine, triphenylphosphite, and n-butylphosphine; and Lewis base compounds containing a nitrogen atom, such as n-butylamine, pyridine, 4-vinylpyridine, acetonitrile, ethylenediamine, N-benzylidenemethylamine, pyrazine, piperidine, and imidazole. The amount of the activity regulator used can be adjusted appropriately depending on the compound used.

[0053] Furthermore, other optional components such as a coupling agent, a radical generator, a diisocyanate compound, a polyfunctional (meth)acrylate compound, an activator, an elastomer, an antioxidant, an ultraviolet absorber, and a light stabilizer may be used.

[0054] [Resin Sheet for Semiconductor Manufacturing Process Comprising Thermosetting Cycloolefin Resin] When the resin sheet for semiconductor manufacturing process of the present invention comprises a thermosetting cycloolefin resin, the resin sheet for semiconductor manufacturing process of the present invention can be produced, for example, by the following first manufacturing method. That is, the resin sheet can be produced by a manufacturing method (first manufacturing method) for a resin sheet for semiconductor manufacturing process comprising the steps of: filling a cycloolefin monomer into a mold having a cavity with a thickness of 0.5 to 3.0 mm (a cavity having a width of 0.5 to 3.0 mm in the thickness direction); and thermally curing the cycloolefin monomer in the mold.

[0055] The mold for filling the cycloolefin monomer may have a cavity with a thickness corresponding to the thickness of the resin sheet for semiconductor manufacturing process to be obtained, and the thickness (width of the cavity itself in the thickness direction) is 0.5 to 3.0 mm, preferably 0.7 to 2.5 mm, and more preferably 1.0 to 2.0 mm. The size of the mold may also be determined according to the size of the resin sheet for semiconductor manufacturing process to be obtained.

[0056] The method for filling the cycloolefin monomer into a mold having a cavity with a thickness of 0.5 to 3.0 mm is not particularly limited, but it is preferable to fill the mold having a cavity with a thickness of 0.5 to 3.0 mm in the form of a polymerizable composition containing the cycloolefin monomer, the metathesis polymerization catalyst, an activity modifier used as needed, and other optional components used as needed.

[0057] The polymerizable composition is prepared by appropriately mixing the above-mentioned components according to a known method. Alternatively, the polymerizable composition may be prepared by mixing two or more reaction stock solutions using a mixing device or the like. The reaction stock solution does not undergo bulk polymerization with only one solution, but the above-mentioned components are prepared by dividing them into two or more solutions so that mixing all the solutions results in a polymerizable composition containing each component in a predetermined ratio (the total content of each component is 100% by mass). Such combinations of two or more reaction stock solutions include the following two types (a) and (b), depending on the type of metathesis polymerization catalyst used.

[0058] (a): As the metathesis polymerization catalyst, a catalyst that does not have polymerization reaction activity by itself but exhibits polymerization reaction activity when used in combination with an activator can be used. In this case, a reaction stock solution (Liquid A) containing a cycloolefin monomer and an activator and a reaction stock solution (Liquid B) containing a cycloolefin monomer and a metathesis polymerization catalyst are used and mixed to obtain a polymerizable composition. Furthermore, a reaction stock solution (Liquid C) containing a cycloolefin monomer but not containing a metathesis polymerization catalyst or an activator may also be used in combination.

[0059] (b): When a metathesis polymerization catalyst having polymerization activity by itself is used, a polymerizable composition can be obtained by mixing a reaction stock solution (i) containing a cycloolefin monomer with a reaction stock solution (ii) containing a metathesis polymerization catalyst. In this case, the reaction stock solution (ii) is typically prepared by dissolving or dispersing the metathesis polymerization catalyst in a small amount of an inert solvent. Examples of solvents include aromatic hydrocarbons such as toluene, xylene, ethylbenzene, and trimethylbenzene; ketones such as methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-heptanone, and 4-hydroxy-4-methyl-2-pentanone; cyclic ethers such as tetrahydrofuran; diethyl ether, dichloromethane, dimethyl sulfoxide, and ethyl acetate. Among these, aromatic hydrocarbons are preferred, and toluene is more preferred.

[0060] Examples of the mixer used for mixing the reaction stock solutions include an impingement mixer that is generally used in reaction injection molding, as well as low-pressure mixers such as a dynamic mixer and a static mixer.

[0061] A cycloolefin monomer is filled into the mold, preferably in the form of a polymerizable composition, and then thermally cured in the mold, thereby obtaining a resin sheet for use in the semiconductor manufacturing process.

[0062] The heat curing temperature is not particularly limited and may be set depending on the type of cycloolefin monomer and metathesis polymerization catalyst used, but is preferably 40 to 200°C, more preferably 120 to 160°C, and even more preferably 130 to 150°C. The heat curing time is preferably 20 to 120 minutes, more preferably 30 to 90 minutes. By setting the heat curing temperature and time within the above ranges, the glass transition temperature of the resulting cycloolefin resin can be suitably controlled.

[0063] Furthermore, after the heat curing step, the heat-cured cured product may be subjected to secondary heat curing at a temperature higher than the heat curing temperature in the heat curing step. The heating temperature in the secondary heat curing step is preferably 200 to 260°C, more preferably 220 to 250°C, and the heating time is preferably 5 to 30 minutes, more preferably 10 to 20 minutes. By performing secondary heat curing, the glass transition temperature of the resulting cycloolefin resin can be further increased. Note that secondary heat curing may be performed in a mold, or the cured product may be removed from the mold and then subjected to secondary heat curing.

[0064] Furthermore, when the resin sheet for semiconductor manufacturing processes of the present invention contains a thermosetting cycloolefin resin, it can also be manufactured by the following second manufacturing method: That is, it can be manufactured by a manufacturing method (second manufacturing method) for a resin sheet for semiconductor manufacturing processes comprising the steps of obtaining a cycloolefin resin block, slicing the cycloolefin resin block to obtain a sheet-like cycloolefin resin, and polishing the sheet-like cycloolefin resin.

[0065] In the step of obtaining a cycloolefin-based resin block, the method for obtaining the cycloolefin-based resin block is not particularly limited, but may include, as in the first production method, a method in which a polymerizable composition containing a cycloolefin monomer, a metathesis polymerization catalyst, an optional activity modifier, and optional other components is filled into a box-shaped container or the like and thermally cured. As a thermal curing method, as in the first production method, a method of heating to a predetermined temperature may be used, or a method utilizing heat of self-reaction may be used. Furthermore, as in the first production method, secondary thermal curing may be performed if necessary. The temperature and time of thermal curing and the temperature and time of secondary thermal curing may be the same as in the first production method.

[0066] The cycloolefin resin block thus obtained is then sliced ​​to obtain a sheet of cycloolefin resin, which is then polished to obtain a resin sheet for use in the semiconductor manufacturing process.

[0067] The slicing process may be carried out so that the thickness of the resulting sheet is the desired thickness, and may be carried out using, for example, a wire saw, a slicer, a laser, or the like.

[0068] The polishing process is not particularly limited, and any method capable of polishing the sliced ​​surface may be used, such as grindstone polishing, lapping polishing, and buff polishing.

[0069] [Thermoplastic cycloolefin-based resin] Examples of the thermoplastic cycloolefin-based resin include norbornene-based polymers, monocyclic cyclic olefin-based polymers, cyclic conjugated diene-based polymers, vinyl alicyclic hydrocarbon polymers and hydrogenated products thereof. Among these, norbornene-based polymers are preferred because they can further enhance the effects of the present invention.

[0070] Examples of norbornene-based polymers include ring-opening polymers of norbornene-based monomers, ring-opening copolymers of norbornene-based monomers with other monomers copolymerizable with ring-opening copolymerization, hydrogenated products thereof, addition polymers of norbornene-based monomers, addition copolymers of norbornene-based monomers with other monomers copolymerizable with norbornene-based monomers, etc. Among these, hydrogenated products of ring-opening (co)polymers of norbornene-based monomers are preferred from the viewpoint of durability (heat resistance, ozone resistance, etc.).

[0071] Examples of norbornene polymers include those obtained by ring-opening polymerization of one or more norbornene monomers, and those obtained by hydrogenating unsaturated bonds in polymers obtained by ring-opening polymerization as needed. In the present invention, the repeating units are bicyclo[3.3.0]octane-2,4-diyl-ethylene structure and tricyclo[4.3.0.1]octane-2,4-diyl-ethylene structure. ２，５ ]decane-7,9-diyl-ethylene structure, and more preferably the content of these repeating units is 90% by weight or more based on the total repeating units of the norbornene-based polymer. ２，５ ] decane-7,9-diyl-ethylene structure” in a weight ratio of 100:0 to 40:60 is preferred.

[0072] Examples of the monomer having a bicyclo[3.3.0]octane-2,4-diyl-ethylene structure as a repeating unit include norbornene-based monomers having a structure in which a five-membered ring is bonded to a norbornene ring, and more specifically, tricyclo[4.3.0.1]octane-2,4-diyl-ethylene structure. ２，５ ]deca-3,7-diene (dicyclopentadiene) and its derivatives (having a substituent on the ring), 7,8-benzotricyclo[4.3.0.1 ２，５ ]dec-3-ene (methanotetrahydrofluorene) and its derivatives. ２，５ ] As a monomer having a decane-7,9-diyl-ethylene structure as a repeating unit, tetracyclo[4.4.0.1 ２，５.1 ７，１０ ] Deca-3,7-diene (tetracyclododecene) and its derivatives (those having a substituent on the ring) can be mentioned.

[0073] Such norbornene-based polymers can be prepared by, for example, combining a monomer capable of providing a bicyclo[3.3.0]octane-2,4-diyl-ethylene structure with a monomer capable of providing a tricyclo[4.3.0.1]octane-2,4-diyl-ethylene structure. ２，５ ]decane-7,9-diyl-ethylene structure, and a monomer capable of giving the same, while controlling the copolymerization ratio, and then hydrogenating the unsaturated bonds of the resulting polymer as needed. ２，５ ] It can also be obtained by a method of mixing a polymer having a decane-7,9-diyl-ethylene structure as a repeating unit in a predetermined blend ratio.

[0074] The weight average molecular weight (Mw) of the thermoplastic cycloolefin resin is the weight average molecular weight (Mw) converted to polyisoprene as measured by gel permeation chromatography using cyclohexane as a solvent (toluene if the polymer resin is not soluble) and is preferably 5,000 to 100,000, more preferably 8,000 to 80,000, and even more preferably 10,000 to 50,000. By setting the weight average molecular weight within the above range, it is possible to further improve abrasion resistance.

[0075] The molecular weight distribution (weight average molecular weight (Mw) / number average molecular weight (Mn)) of the thermoplastic cycloolefin resin is not particularly limited, but is preferably 1.0 to 10.0, more preferably 1.0 to 4.0, and even more preferably 1.2 to 3.5. The number average molecular weight (Mn) can be measured by the same method as for the weight average molecular weight (Mw).

[0076] The thermoplastic cycloolefin resin preferably contains 5% by weight or less of resin components having a molecular weight of 2,000 or less (i.e., oligomer components), more preferably 3% by weight or less, and even more preferably 2% by weight or less. The amount of oligomer components can be adjusted by the selection of polymerization catalysts and hydrogenation catalysts; reaction conditions such as polymerization and hydrogenation reactions; and temperature conditions in the process of pelletizing the resin into a molding material. The amount of oligomer components can be measured by gel permeation chromatography using cyclohexane (or toluene if the polymer resin is not soluble).

[0077] [Resin Sheet for Semiconductor Manufacturing Process Comprising Thermoplastic Cycloolefin Resin] When the resin sheet for semiconductor manufacturing process of the present invention comprises a thermoplastic cycloolefin resin, the resin sheet for semiconductor manufacturing process of the present invention can be produced, for example, by the following third production method (third production method) comprising the steps of plasticizing a thermoplastic cycloolefin resin, and extruding the plasticized cycloolefin resin into a sheet and then cooling it to form it into a sheet having a thickness of 0.5 to 3 mm.

[0078] In the third production method, the plasticization of the thermoplastic cycloolefin resin and the extrusion into a sheet are preferably carried out using an extruder such as a single-screw extruder or a twin-screw extruder, etc. Specifically, it is preferable to use an extruder equipped with a T-die at the discharge port.

[0079] In the method using an extruder equipped with a T-die at the discharge port, first, a thermoplastic cycloolefin resin in a predetermined shape such as pellets is fed into the extruder and kneaded in the extruder to plasticize the thermoplastic cycloolefin resin. The plasticized thermoplastic cycloolefin resin is then extruded into a sheet from the T-die equipped at the discharge port of the extruder and cooled to form a cycloolefin resin sheet having a thickness of 0.5 to 3 mm, thereby obtaining a resin sheet for semiconductor manufacturing processes containing the thermoplastic cycloolefin resin.

[0080] The extruder may be either a single-screw extruder or a twin-screw extruder, but a twin-screw extruder is preferred from the viewpoint of productivity. The sheet thickness can be adjusted, for example, by the type of T-die used, the kneading temperature in the twin-screw extruder, and the cooling temperature after extrusion.

[0081] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. The "parts" are by weight unless otherwise specified. The test methods used in these examples and comparative examples are as follows.

[0082] <Surface Roughness (Ra)> The surface roughness (Ra) of the resin sheet for the semiconductor manufacturing process was measured using a white light interferometer (NweView7300, manufactured by Zygo Corporation).

[0083] <Glass transition temperature> A portion was taken from the resin sheet for semiconductor manufacturing process, and used as a measurement sample. Measurement was performed using a differential scanning calorimeter (manufactured by Hitachi High-Tech Science Corporation) at a temperature rise rate of 10°C / min to measure the glass transition temperature of the cycloolefin resin constituting the resin sheet for semiconductor manufacturing process. Note that for Comparative Example 1, the melting point of the polyamide resin constituting the sheet was measured using the same method.

[0084] <Acid Resistance> Potassium permanganate was dissolved in distilled water and adjusted to pH 2 using dilute nitric acid. Potassium permanganate was then added to this solution so that the potassium permanganate concentration was 4 wt %, thereby preparing an acidic solution. A 100 mm x 100 mm, 1 mm thick resin sheet for semiconductor manufacturing processes was immersed in the acidic solution prepared above at 50°C for 48 hours. The sample dimensions and mass were measured before and after immersion, and the acid resistance was evaluated according to the following criteria: ∘: The rate of change in the sample dimensions and mass before and after immersion was both within ±1.2%. Δ: The rate of change in the sample dimensions and mass before and after immersion was both within ±1.5% (excluding cases rated ∘). ×: The rate of change in either or both of the sample dimensions and mass before and after immersion was greater than ±1.5%.

[0085] <Alkali Resistance> An aqueous potassium hydroxide solution with a pH of 13 was prepared, and this was used as the alkaline solution. A resin sheet for semiconductor manufacturing processes, measuring 100 mm x 100 mm and 1 mm thick, was then immersed in the alkaline solution prepared above at 50°C for 48 hours. The sample dimensions and mass were measured before and after immersion, and the alkali resistance was evaluated according to the following criteria: Good: The rate of change in the sample dimensions and mass before and after immersion was both within ±1.2%. Fair: The rate of change in the sample dimensions and mass before and after immersion was both within ±1.5% (excluding cases rated as Good above). Bad: The rate of change in either or both of the sample dimensions and mass before and after immersion was greater than ±1.5%.

[0086] <Abrasion Resistance> A 100 mm x 100 mm, 2 mm thick resin sheet for semiconductor manufacturing processes was subjected to a Taber abrasion test using a rotary abrasion tester (manufactured by Toyo Seiki Seisaku-sho, Ltd.). The material of the abrasion wheel was H18, and the amount of abrasion was measured after 1000 rotations under conditions of a load of 9.8 N and a rotation speed of 60 rpm, and evaluated according to the following criteria: ⊚: Amount of abrasion is 35 mg or less; ◯: Amount of abrasion is more than 35 mg but not more than 60 mg; Δ: Amount of abrasion is more than 60 mg but not more than 100 mg; ×: Amount of abrasion is more than 100 mg.

[0087] <Inorganic content> A portion of the resin sheet for semiconductor manufacturing process was sampled and weighed into a polytetrafluoroethylene container, to which nitric acid was added. The container was then sealed, and microwave decomposition was performed at a maximum of 240 ° C. / 60 bar using a microwave decomposition device (MultiWave 3000, manufactured by Anton Paar), and the resulting decomposition solution was adjusted to a constant volume of 25 ml to serve as a test solution. The obtained test solution and a standard solution of known concentration were then introduced into an ICP mass spectrometer (Agilent 7500, manufactured by Agilent Technologies), and the concentrations of 13 types of metals (Al, Ca, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Ni, Ti, Zn) were calculated using the calibration curve method. ◯: The content of all 13 types of metals is less than 100 mg / kg. ×: The content of at least one of the 13 types of metals is 100 mg / kg or more.

[0088] <Cutting processability> A resin sheet for semiconductor manufacturing process measuring 100 mm x 100 mm and 1 mm thick was cut in half using an NC processing machine, the shape of the edge surface was visually observed, and the cutting processability was evaluated according to the following criteria: ◯: Cuttable well, and no sagging or burrs were observed. △: Cuttable, although sagging or burrs were observed. ×: Resin adhered to parts of the processing machine, causing problems with the parts of the processing machine, making continuous cutting difficult.

[0089] Example 1 A RIM monomer (manufactured by Zeon Corporation) was prepared and used as a preliminary blend liquid (i). The RIM monomer contained 90 parts of dicyclopentadiene and 10 parts of tricyclopentadiene as norbornene-based monomers.

[0090] A pre-blended solution (ii) was obtained by dissolving 0.3 parts of a ruthenium catalyst (Zhan1N) represented by the following formula (7) as a metathesis polymerization catalyst, 30 parts of 2,6-di-t-butyl-p-cresol (BHT, antioxidant), and 30 parts of triphenylphosphine in 39.7 parts of cyclopentanone. (In the formula, Mes represents a mesityl group.)

[0091] The molding dies used were a flat-plate reaction injection molding die consisting of two stainless steel plates with an internal space of 100 mm length x 100 mm width x 1 mm thickness, and a flat-plate reaction injection molding die consisting of two stainless steel plates with an internal space of 100 mm length x 100 mm width x 2 mm thickness. These reaction injection molding dies were designed so that a reaction liquid injection hole was provided at the bottom of one of the stainless steel plates.

[0092] The premixed liquid (i) and premixed liquid (ii) prepared above were mixed in a ratio of (i):(ii) = 100:3.5 (mass ratio), degassed in a vacuum, and then injected into a reaction injection mold through the reaction liquid injection hole. Heating was performed in an oven heated to 40°C for 30 minutes, followed by heating at 130°C for 60 minutes to obtain a polymerized and cured cycloolefin resin sheet, which was used as a resin sheet for semiconductor manufacturing processes. In this example, sheets measuring 100 mm x 100 mm x 1 mm thick and 100 mm x 100 mm x 2 mm thick were obtained (the same applies to the examples and comparative examples described below). The obtained sheets were then measured and evaluated according to the above-mentioned methods. The results are shown in Table 1.

[0093] The cycloolefin resin sheet obtained in Example 1 after polymerization and curing was further subjected to secondary heat curing at 230°C for 15 minutes to obtain a resin sheet for semiconductor manufacturing process, which was then measured and evaluated according to the above-described methods. The results are shown in Table 1.

[0094] Example 3: Preliminary mixture (i) and preliminary mixture (ii) were prepared in the same manner as in Example 1, mixed in a ratio of (i):(ii) = 100:3.5 (mass ratio), degassed in a vacuum, filled into a container measuring 40 cm long x 40 cm wide x 10 cm deep, and left for 60 minutes to allow the polymerization and curing reaction to proceed, yielding a cycloolefin resin block. In Example 3, the polymerization and curing reaction was allowed to proceed by self-reaction heat, with the reaction temperature reaching a maximum of 195°C. The obtained cycloolefin resin block was then sliced ​​using a wire saw to obtain sheets measuring 100 mm x 100 mm x 1 mm thick and 100 mm x 100 mm x 2 mm thick. The surfaces of the obtained sheets were polished using lapping polishing to obtain resin sheets for semiconductor manufacturing processes. The obtained sheets were then measured and evaluated according to the methods described above. The results are shown in Table 1.

[0095] Example 4: 100 parts of a cycloolefin resin (ZEONEX 1420R manufactured by Zeon Corporation, glass transition temperature 136°C) was added to a twin-screw extruder equipped with a T-die at the discharge port, plasticized by kneading in the twin-screw extruder, extruded through a T-die, and cooled to obtain a cycloolefin resin sheet. In Example 4, by changing the type of T-die, sheets with thicknesses of 1 mm and 2 mm were obtained. The obtained sheets were then cut to a size of 100 mm x 100 mm to obtain resin sheets for semiconductor manufacturing processes with sizes of 100 mm x 100 mm x 1 mm thick and 100 mm x 100 mm x 2 mm thick. Measurements and evaluations were performed according to the above methods. The results are shown in Table 1. In Example 4, the twin-screw extruder used was a twin-screw extruder cylinder (manufactured by Toshiba Corporation, L / D=42) with a screw having a total length of 1,848 mm and a diameter of 44 mm. Kneading zones were provided at positions of 685 mm, 920 mm, 1,190 mm, and 1,580 mm from the starting point, with L / D=2, L / D=5, L / D=5, and L / D=4 from the closest to the starting point, with the starting point being the upper end of the most upstream disk constituting the screw, and extrusion was carried out at a screw rotation speed of 200 rpm.

[0096] <Comparative Example 1> Commercially available polyamide resin (PA6) sheets (thickness 1 mm and thickness 2 mm) were prepared and cut to a size of 100 mm × 100 mm to obtain resin sheets for semiconductor manufacturing processes having a size of 100 mm × 100 mm × thickness 1 mm and a size of 100 mm × 100 mm × thickness 2 mm, and measurements and evaluations were carried out according to the above-mentioned methods. The results are shown in Table 1.

[0097] Comparative Example 2 A resin sheet for the semiconductor manufacturing process was obtained in the same manner as in Example 4, except that a cycloolefin resin (ZEONOR1060R manufactured by Zeon Corporation, glass transition temperature 100°C) was used, and measurements and evaluations were carried out according to the methods described above. The results are shown in Table 1.

[0098]

[0099] As shown in Table 1, it can be confirmed that a resin sheet for a semiconductor manufacturing process containing a cycloolefin resin having a glass transition temperature of 115°C or higher has excellent acid resistance, alkali resistance, abrasion resistance, and cutting workability, and effectively suppresses the elution of metal ions.

Claims

1. A resin sheet for semiconductor manufacturing processes containing a cycloolefin resin having a glass transition temperature of 115°C or higher.

2. The resin sheet for semiconductor manufacturing processes according to claim 1, which has a surface roughness (Ra) of 0.1 μm or less.

3. A resin sheet for use in semiconductor manufacturing processes according to claim 1 or 2, wherein the cycloolefin resin is obtained by thermally curing a cycloolefin monomer.

4. The resin sheet for semiconductor manufacturing processes according to claim 3, wherein the cycloolefin resin is obtained by thermally curing a monomer mixture liquid comprising dicyclopentadiene and / or tricyclopentadiene.

5. A polishing frame made of the resin sheet for use in the semiconductor manufacturing process according to any one of claims 1 to 4.

6. A frame material for a wafer holding pad, comprising the resin sheet for semiconductor manufacturing processes according to any one of claims 1 to 4.

7. A method for producing a resin sheet for use in a semiconductor manufacturing process according to any one of claims 1 to 4, comprising the steps of: filling a cycloolefin monomer into a mold having a cavity with a thickness of 0.5 to 3.0 mm; and thermally curing the cycloolefin monomer in said mold.

8. The method for producing a resin sheet for a semiconductor manufacturing process according to claim 7, further comprising, after the heat curing step, a step of secondary heat curing the heat-cured product at a temperature higher than the heat curing temperature in the heat curing step.

9. The method for producing a resin sheet for semiconductor manufacturing processes according to claim 8, wherein the heating temperature in the secondary heat curing step is 200 to 260°C.

10. A method for producing a resin sheet for use in a semiconductor manufacturing process according to any one of claims 1 to 4, comprising the steps of: obtaining a cycloolefin resin block; slicing the cycloolefin resin block to obtain a sheet of cycloolefin resin; and polishing the sheet of cycloolefin resin.

11. A method for producing a resin sheet for use in a semiconductor manufacturing process according to any one of claims 1 to 4, comprising the steps of: plasticizing a thermoplastic cycloolefin resin; and extruding the plasticized cycloolefin resin into a sheet and then cooling it to form it into a sheet having a thickness of 0.5 to 3 mm.

12. Use of the resin sheet for semiconductor manufacturing process according to any one of claims 1 to 4 in the semiconductor manufacturing process.

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