Method of using the temporary fixing composition

Abstract

To provide a material that is excellent in all of heat resistance, ease of film formation, and ease of cleaning the film after surface protection is completed. The composition contains a vinyl alcohol copolymer obtained by saponifying a vinyl acetate copolymer obtained by copolymerizing vinyl acetate with a (meth)acrylic monomer. After curing, the tensile shear adhesive strength to SUS304 at 23.5°C measured by a method in accordance with JIS K 6850 is 2 N / mm 2 Furthermore, when the composition is heated at 100°C for 60 minutes, allowed to cool naturally to 30°C, and then subjected to thermogravimetric analysis at a temperature increase rate of 10°C / min from 30°C to 300°C in a nitrogen gas atmosphere at normal pressure, the weight loss of the composition for forming a protective film at 300°C is 3.0% or less relative to the weight of the composition for forming a protective film at 30°C.

Description

[Technical field]

[0001] The present invention relates to a method for using a temporary fixing composition. [Background technology]

[0002] When processing a substrate (e.g., glass, semiconductor wafers, resin molded products, etc.), a method is known in which a protective film is formed on the surface of the substrate to protect non-processed areas, and then the protective film is removed after processing.

[0003] This method is used, for example, in the processing of semiconductor wafers. A semiconductor wafer is a laminate in which an insulating film and a functional film are laminated on the surface of a semiconductor substrate such as silicon, and semiconductor chips are manufactured by irradiating the semiconductor wafer with a laser beam to form grooves and then cutting along the grooves.

[0004] However, when a semiconductor wafer is irradiated with laser light, the laser light is absorbed by the semiconductor substrate, generating melted matter and pyrolyzed matter of the semiconductor substrate, which then adheres to the surfaces of the semiconductor wafer and semiconductor chips as deposits (debris).

[0005] In this situation, a method (laser dicing) has been proposed in which a protective film that can be removed by washing with water is formed on the surface of a semiconductor wafer, and then laser light is irradiated to process the wafer. By irradiating laser light through the protective film, debris is caused to adhere to the surface of the protective film, and the debris can be removed together with the protective film by washing with water.

[0006] As such a protective film forming agent, for example, a protective film forming agent containing a solution in which a water-soluble resin and a water-soluble laser light absorbent are dissolved has been proposed (Patent Document 1). The protective film forming agent described in Patent Document 1 can effectively prevent peeling of the protective film caused by the pressure of vapors of substrate pyrolysis products caused by laser light.

[0007] Also, a composition for forming a protective film has been proposed, which contains a water-soluble polymer and a solvent, and the solvent contains water and a propylene glycol derivative in a mass ratio of 9:1 to 0:10 (Patent Document 2). The protective film forming agent described in Patent Document 2 has excellent coatability to a substrate and excellent processability of the formed protective film, so that processing onto the substrate can be carried out efficiently. In addition, the protective film forming agent described in Patent Document 2 has excellent storage stability, so that processing onto the substrate can be carried out efficiently even after long-term storage. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] JP 2006-140311 A [Patent Document 2] JP 2020-066666 A Summary of the Invention [Problem to be solved by the invention]

[0009] Incidentally, the problem of preventing adhesion of deposits on the processing surface of a workpiece is not limited to laser processing, but can also occur in micro-hole processing, flattening of printed wiring, and the like.

[0010] In addition, in the deposition process, a coating called a deposition film is formed by the reaction product of the deposition reaction. If the deposition film is deposited in the chamber of the deposition device, it can adversely affect the vacuum properties in the case of vacuum deposition technology, and can also become a source of contamination for thin film products and affect the purity of the thin film products. In addition, it becomes difficult to remove the deposition film. Therefore, in order to prevent the deposition film from accumulating in the chamber itself, a shield is provided in the deposition device, and the deposition film is deposited on the surface of the shield. However, when the deposition process is repeated, the deposition film attached to the shield can peel off from the shield due to stress, and can become a source of contamination for thin film products. Therefore, it is required to provide a mechanism for easily removing the deposition film attached to the shield.

[0011] Not only for protecting the material surface during laser processing, but also for other processes such as micro-hole processing, flattening of printed wiring, and deposition processing, the protective film is required to have heat resistance sufficient to prevent the protective film from peeling off from the substrate even under high temperature conditions. In this respect, there is still room for improvement in the protective film-forming compositions described in Patent Documents 1 and 2.

[0012] Further, the composition for forming a protective film is required to have not only heat resistance but also ease of film formation, ease of cleaning of the film after completion of surface protection, and the like.

[0013] The present invention has been made in consideration of such problems, and aims to provide a material that is excellent in all of heat resistance, ease of film formation, and ease of cleaning of the film after surface protection is completed. [Means for solving the problem]

[0014] As a result of intensive research into achieving the above object, the present inventors have found that the above object can be achieved by using a vinyl alcohol copolymer obtained by saponifying a vinyl acetate copolymer obtained by copolymerizing vinyl acetate with a (meth)acrylic monomer, and have thus completed the present invention. Specifically, the present invention provides the following.

[0015] The first aspect of the present invention is a composition for forming a protective film, the composition for forming a protective film containing a vinyl alcohol-based copolymer obtained by saponifying a vinyl acetate-based copolymer obtained by copolymerizing vinyl acetate and a (meth)acrylic monomer, and having a tensile shear adhesive strength to SUS304 at 23.5°C after curing, measured by a method in accordance with JIS K 6850, of 2 N / mm 2 The present invention provides a composition for forming a protective film, wherein when the composition for forming a protective film is heated at 100°C for 60 minutes, naturally cooled to 30°C, and then subjected to thermogravimetric analysis at a heating rate of 10°C / min from 30°C to 300°C under a nitrogen gas atmosphere at normal pressure, the weight loss of the composition for forming a protective film at 300°C is 3.0% or less relative to the weight of the composition for forming a protective film at 30°C.

[0016] According to the first aspect of the invention, the vinyl alcohol copolymer contained in the composition for forming a protective film is obtained by saponifying a vinyl acetate copolymer obtained by copolymerizing vinyl acetate and a (meth)acrylic monomer. This makes it possible to easily form a protective film on the surface of an object by applying the composition for forming a protective film to the object.

[0017] In addition, after curing, the tensile shear adhesive strength to SUS304 at 23.5°C measured according to a method in accordance with JIS K 6850 was 2N / mm 2 This provides the protective film with sufficient adhesion to the semiconductor substrate.

[0018] Moreover, the composition for forming a protective film has a weight loss of 3.0% or less at 300° C., which is higher heat resistance than conventionally known compositions for forming a protective film.

[0019] In addition, since the composition for forming a protective film contains a vinyl alcohol-based copolymer, the protective film can be easily peeled off from the surface of the object after surface protection is completed by simply pouring warm water onto the protective film.

[0020] Therefore, according to the first aspect of the invention, it is possible to provide a composition that is excellent in all of the performance required of a composition for forming a protective film, namely, high heat resistance of the film, ease of film formation, and ease of cleaning of the film after surface protection is completed.

[0021] The second aspect of the invention provides a composition for forming a protective film, which is used for a workpiece that undergoes one or more types of processing selected from laser processing, microhole processing, and flat processing of printed wiring, and / or an adhesion prevention plate of a vapor deposition device, in the first aspect of the invention.

[0022] As described above, the protective film, which is a cured product of the composition, has higher heat resistance than conventionally known water-soluble compositions for forming a protective film. Therefore, according to the second aspect of the invention, a composition for forming a protective film can be provided that can adequately protect not only workpieces to be laser processed, but also workpieces to be processed in which fine holes are drilled or flattened printed wiring, and adhesion prevention plates of vapor deposition devices.

[0023] The invention according to a third aspect provides a method for using a composition for forming a protective film, the method including a protective film formation step of coating a processing surface of a workpiece that is to be subjected to one or more types of processing selected from laser processing, microhole processing, and flattening of printed wiring with the composition for forming a protective film in the invention according to the first or second aspect, thereby forming a protective film on the processing surface, a processing step of performing the processing on the processing surface via the protective film, and a cleaning step of washing the processed workpiece with a cleaning solution at 80°C or higher, thereby removing the protective film from the processing surface.

[0024] The invention according to a fourth aspect provides a method for using a composition for forming a protective film, the method including: a protective film formation step of coating an adhesion prevention plate of a vapor deposition apparatus with the composition for forming a protective film in the invention according to the first or second aspect to form a protective film on a surface of the adhesion prevention plate; and a cleaning step of washing the adhesion prevention plate on whose surface a deposition film and the protective film are formed by deposition of a reaction product of a vapor deposition reaction with a cleaning solution at 80°C or higher to remove the deposition film and the protective film from the surface of the deposition prevention plate.

[0025] According to the third and fourth features of the invention, a method can be provided that can adequately protect not only workpieces that undergo laser processing, but also workpieces that undergo micro-hole processing or flattening of printed wiring, and adhesion prevention plates of vapor deposition devices.

[0026] The invention according to a fifth feature provides a method of use according to the invention according to the third or fourth feature, in which the cleaning step is ultrasonic cleaning in which an acoustic stream is generated in the cleaning liquid by placing an object to be cleaned in a cleaning tank filled with the cleaning liquid at 80° C. or higher, and high-frequency power is supplied to the inside of the cleaning tank, or an ultrasonic vibration is generated in the cleaning liquid and in the cleaning liquid by a transducer.

[0027] According to the fifth feature of the present invention, the protective film after surface protection can be cleaned more easily and cleanly.

[0028] A sixth aspect of the present invention is a temporary fixing composition, the temporary fixing composition containing a vinyl alcohol-based copolymer obtained by saponifying a vinyl acetate-based copolymer obtained by copolymerizing vinyl acetate and a (meth)acrylic monomer, and having a tensile shear adhesive strength to SUS304 at 23.5°C after curing, as measured by a method in accordance with JIS K 6850, of 2 N / mm 2 The present invention provides a temporary fixing composition, in which when the temporary fixing composition is heated at 100° C. for 60 minutes, naturally cooled to 30° C., and then subjected to thermogravimetric analysis at a temperature increase rate of 10° C. / min from 30° C. to 300° C. in a nitrogen gas atmosphere at normal pressure, the weight loss of the temporary fixing composition at 300° C. is 3.0% or less relative to the weight of the temporary fixing composition at 30° C.

[0029] Nonmetallic materials such as silicon wafers, sapphire glass, ceramic materials, optical glass, quartz crystal, magnetic materials, and other metallic materials are surface-treated before use. Surface treatment of nonmetallic materials includes flat surface polishing, and surface treatment of metallic materials includes grinding. These surface treatments are performed after the nonmetallic or metallic workpiece is temporarily fixed on a base using a temporary fixing composition. By performing temporary fixing, the nonmetallic or metallic material can be fixed against forces in the shear direction, allowing efficient surface treatment.

[0030] According to the sixth aspect of the invention, the vinyl alcohol copolymer contained in the temporary fixing composition is obtained by saponifying a vinyl acetate copolymer obtained by copolymerizing vinyl acetate and a (meth)acrylic monomer. This makes it possible to easily temporarily fix the workpiece on the base by applying the temporary fixing composition onto the base and placing the workpiece on the base via the temporary fixing composition. The temporary fixing composition has a weight loss of 3.0% or less at 300°C, which is higher heat resistance than conventionally known temporary fixing compositions.

[0031] In addition, since the composition for forming a protective film contains a vinyl alcohol-based copolymer, after the temporary fixing is completed, the pressure-sensitive adhesive layer, which is the cured product of the temporary fixing composition, can be easily washed by simply pouring warm water onto the pressure-sensitive adhesive layer after the temporary fixing is completed.

[0032] Therefore, according to the sixth aspect of the invention, a composition can be provided that can be used not only to protect the surface of an object during laser processing or the like, but also to temporarily fix a workpiece made of a non-metallic material or a metallic material.

[0033] A seventh aspect of the invention provides a temporary fixing composition according to the sixth aspect of the invention, which is used for surface polishing and / or metal grinding.

[0034] According to the seventh aspect of the invention, since appropriate temporary fixation is achieved, the non-metallic or metallic material to be processed can be fixed against forces in the shear direction, and surface processing can be performed more efficiently.

[0035] An eighth aspect of the invention provides a method for using the temporary fixing composition, the method including: a temporary fixing step of applying the temporary fixing composition in the invention according to the sixth or seventh aspect onto a base, and temporarily fixing a workpiece onto the base via the temporary fixing composition; a processing step of subjecting the workpiece temporarily fixed on the base to surface polishing and / or metal grinding; and a peeling step of subjecting at least the temporary fixing surface between the workpiece and the base to an aqueous material at 80° C. or higher, and peeling the workpiece from the base.

[0036] According to the eighth feature of the invention, since appropriate temporary fixation is achieved, the non-metallic or metallic material to be processed can be fixed against forces in the shear direction, and surface processing can be performed more efficiently. Effect of the Invention

[0037] According to the present invention, a material can be provided that is excellent in heat resistance, ease of film formation, and ease of cleaning of the film after surface protection. This material can be used not only to protect the surface of an object during laser processing, etc., but also to temporarily fix a workpiece to a base when performing surface polishing of nonmetallic materials or grinding of metallic materials. [Brief description of the drawings]

[0038] [Figure 1] FIG. 1 is a schematic diagram showing a state in which a first workpiece 1 is subjected to laser processing in a state in which a first protective film 2 is formed on a first processing surface 1A of the first workpiece 1. [Diagram 2] FIG. 2 is a schematic diagram showing the process of using a drill 50 to cut the pilot hole H in the second workpiece 11 from the second machining surface 11A of the second workpiece 11, in which the pilot hole H has been drilled, toward the opposing surface 11B opposite the second machining surface 11A, thereby performing micro-hole machining on the second workpiece 11. [Diagram 3] FIG. 3 is a schematic diagram showing a state where a micro-hole is drilled using a drill 50 in a state where the second protective film 12 is not formed on the second processing surface 11A of the second workpiece 11. As shown in FIG. [Figure 4] FIG. 4 is a schematic diagram showing the ultrasonic cleaning of the first workpiece 1 after the laser processing described with reference to FIG. [Diagram 5] FIG. 5 is a flow chart showing an example of a temporary fixing step in the procedure for manufacturing a semiconductor product by temporarily fixing a semiconductor wafer according to this embodiment. [Figure 6] FIG. 6 is a flow chart showing an example of processing steps in a procedure for temporarily fixing a semiconductor wafer according to this embodiment and manufacturing a semiconductor product. [Figure 7]FIG. 7 is a flow chart showing an example of a peeling step in the procedure for temporarily fixing a semiconductor wafer according to this embodiment to manufacture a semiconductor product. [Figure 8] FIG. 8 is a schematic diagram showing an adhesion prevention plate of a physical vapor deposition apparatus (PVD apparatus) used in the test example. [Figure 9] FIG. 9 shows the results of thermogravimetric analysis (TGA) of the cured films obtained in the test examples. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] Specific embodiments of the present invention will be described in detail below. However, the present invention is not limited to the following embodiments and can be modified as appropriate within the scope of the object of the present invention.

[0040] <Composition> The composition described in this embodiment is suitably used as a composition for forming a protective film on the surface of an object in laser processing, etc., or as a composition for temporarily fixing a workpiece to a base when performing surface polishing of nonmetallic materials or grinding of metallic materials, etc. The composition contains a vinyl alcohol-based copolymer obtained by saponifying a vinyl acetate-based copolymer obtained by copolymerizing vinyl acetate and a (meth)acrylic monomer.

[0041] [Vinyl alcohol copolymer] The vinyl alcohol copolymer is prepared by saponifying a vinyl acetate copolymer obtained by copolymerizing vinyl acetate with a (meth)acrylic monomer.

[0042] [Vinyl acetate monomer] The vinyl acetate monomer is used to impart adhesion to the cured film when the composition is applied to the surface of the object to form a cured film, and also to make the cured film easily peelable from the surface of the object by simply pouring warm water on it after use.

[0043] When vinyl acetate is polymerized, other monomers may be copolymerized within the scope of the present invention. Examples of such other monomers include α-olefins such as ethylene and propylene; (meth)acrylic acid and its salts; (meth)acrylic acid esters such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, i-propyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, dodecyl (meth)acrylate, and octadecyl (meth)acrylate; (meth)acrylamide; N-methyl (meth)acrylamide, N-ethyl (meth)acrylamide, N,N-dimethyl (meth)acrylamide, diacetone (meth)acrylamide, (meth)acrylamidopropanesulfonic acid and its salts; (meth)acrylamide, N-ethyl (meth)acrylamide, N,N-dimethyl (meth)acrylamide, diacetone (meth)acrylamide, (meth)acrylamidopropanesulfonic acid and its salts; (Meth)acrylamide derivatives such as acrylamidopropyldimethylamine and its salts or its quaternary salts, and N-methylol (meth)acrylamide and its derivatives; vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, i-propyl vinyl ether, n-butyl vinyl ether, i-butyl vinyl ether, t-butyl vinyl ether, dodecyl vinyl ether, and stearyl vinyl ether; nitriles such as acrylonitrile and methacrylonitrile; vinyl halides such as vinyl chloride and vinyl fluoride; vinylidene halides such as vinylidene chloride and vinylidene fluoride; allyl compounds such as allyl acetate and allyl chloride; unsaturated dicarboxylic acids such as maleic acid, itaconic acid, and fumaric acid, and Examples of the copolymer include salts thereof or esters thereof, vinyl silyl compounds such as vinyltrimethoxysilane, isopropenyl acetate, etc. The amount of such other monomers copolymerized is usually 5 mol % or less.

[0044] [(Meth)acrylic monomer] The (meth)acrylic monomer is used to impart heat resistance to the protective film.

[0045] The (meth)acrylic monomer refers to acrylic acid, methacrylic acid, or a derivative thereof. Specifically, in addition to acrylic acid and methacrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, i-propyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate, n-pentyl (meth)acrylate, i-pentyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, cyclohex ... Examples of the (meth)acrylic acid esters include diethylhexyl (meth)acrylate; hydroxyl group-containing (meth)acrylic acid esters such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 3-hydroxypropyl (meth)acrylate; (meth)acrylic acid salts such as ammonium (meth)acrylate, sodium (meth)acrylate, and potassium (meth)acrylate; (meth)acrylamides such as (meth)acrylamide; and (meth)acrylonitriles such as (meth)acrylonitrile.

[0046] [Saponification degree] In this embodiment, the lower limit of the saponification degree of the vinyl alcohol copolymer is preferably 60 mol% or more, more preferably 65 mol% or more, and even more preferably 70 mol% or more. If the saponification degree is too low, the solubility of the vinyl alcohol polymer in hot water is insufficient, and even if hot water is poured onto the cured film of the composition, the cured film may not be removed from the surface of the object, which is not preferable.

[0047] In this embodiment, the upper limit of the saponification degree of the vinyl alcohol copolymer is preferably 99.9 mol% or less. If the saponification degree exceeds 99.9 mol%, industrial production of the vinyl alcohol copolymer becomes difficult. In addition, from the viewpoint of storage stability of the composition, the upper limit of the saponification degree is more preferably 95 mol% or less, and even more preferably 90 mol% or less.

[0048] In the present embodiment, the degree of saponification is a value measured by the method for measuring the degree of saponification described in JIS-K6726 (1994). In this case, units other than vinyl alcohol units, vinyl acetate units, and polyfunctional monomer units, even if they are contained, are small in amount and can usually be ignored.

[0049] [Weight average molecular weight] The lower limit of the weight average molecular weight of the vinyl alcohol copolymer is preferably at least 10,000, more preferably at least 13,000, and even more preferably at least 15,000. If the weight average molecular weight is too small, the cured product may not have sufficient tensile strength, which is undesirable.

[0050] In the present embodiment, the weight average molecular weight is measured by GPC (gel permeation chromatography) in terms of polystyrene.

[0051] [Method of producing vinyl alcohol copolymer] The method for producing the vinyl alcohol polymer is not particularly limited. For example, the method includes a copolymerization step of copolymerizing vinyl acetate with a polyfunctional monomer having a plurality of ethylenic double bonds to obtain a vinyl ester copolymer, and a saponification step of saponifying the vinyl ester copolymer.

[0052] (Copolymerization process) Examples of the polymerization method include bulk polymerization, solution polymerization, suspension polymerization, and emulsion polymerization. The polymerization can be carried out without a solvent or in the presence of an alcohol-based solvent. Among them, a bulk polymerization method without a solvent or a solution polymerization method using an alcohol-based solvent is preferable. The alcohol-based solvent is not particularly limited, and methanol, ethanol, propanol, etc. can be used. These can be used alone or in combination of two or more kinds. The polymerization method is not particularly limited, and can be any of batch polymerization, semi-batch polymerization, continuous polymerization, and semi-continuous polymerization.

[0053] The polymerization temperature is not particularly limited, but is preferably 0 to 200° C., more preferably 30 to 140° C. If the polymerization temperature is lower than 0° C., a sufficient polymerization rate may not be obtained. If the polymerization temperature is higher than 200° C., there is a concern that vinyl acetate and other monomers may be decomposed.

[0054] The temperature can be controlled by balancing the heat generated by the polymerization with the heat dissipated from the surface of the polymerization vessel. Another method is to control the temperature by using an external jacket containing a suitable heat medium. From the viewpoint of safety, the latter method is preferred.

[0055] The polymerization initiator may be selected from known initiators (e.g., azo initiators, peroxide initiators, redox initiators, etc.) according to the polymerization method. Examples of the azo initiator include 2,2'-azobisisobutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), etc. Examples of the peroxide initiator include percarbonate compounds such as diisopropyl peroxydicarbonate, di-2-ethylhexyl peroxydicarbonate, and diethoxyethyl peroxydicarbonate; perester compounds such as t-butyl peroxyneodecanate, α-cumyl peroxyneodecanate, and t-butyl peroxydecanate; acetylcyclohexylsulfonyl peroxide; and 2,4,4-trimethylpentyl-2-peroxyphenoxyacetate. These initiators may be combined with potassium persulfate, ammonium persulfate, hydrogen peroxide, etc. to form an initiator. Examples of redox initiators include initiators that combine the above-mentioned peroxides with reducing agents such as sodium hydrogen sulfite, sodium hydrogen carbonate, tartaric acid, L-ascorbic acid, and Rongalite. When polymerization is performed at high temperatures, coloring due to decomposition of vinyl acetate may be observed. In that case, there is no problem in adding an antioxidant such as tartaric acid to the polymerization system in an amount of about 1 to 100 ppm relative to vinyl acetate in order to prevent coloring.

[0056] In the polymerization of vinyl acetate, a chain transfer agent may be added to adjust the degree of polymerization of the vinyl alcohol polymer. Examples of the chain transfer agent include aldehydes such as acetaldehyde, propionaldehyde, butylaldehyde, and benzaldehyde; ketones such as acetone, methyl ethyl ketone, hexanone, and cyclohexanone; mercaptans such as 2-hydroxyethanethiol; and halogenated hydrocarbons such as trichloroethylene and perchloroethylene. Among these, aldehydes and ketones are preferably used. The amount of the chain transfer agent is determined according to the chain transfer constant of the chain transfer agent to be added and the degree of polymerization of the desired vinyl alcohol polymer, but is generally desirably 0.1 to 10% by mass relative to vinyl acetate.

[0057] (Saponification process) As a method for saponifying a vinyl alcohol copolymer, a conventionally known method using an alkali catalyst or an acid catalyst can be used. Among them, a method in which an alkali such as sodium hydroxide is added to a methanol solution of a vinyl alcohol copolymer or a mixed solution of a vinyl alcohol copolymer in methanol, water, methyl acetate, etc., and the mixture is stirred to perform alcoholysis is industrially preferred.

[0058] Thereafter, the obtained lump, gel or granule may be pulverized, the alkali added as necessary may be neutralized, the solid and liquid components may be separated, and the solid may be dried to obtain a vinyl alcohol copolymer.

[0059] [Water-based solvent] If necessary, the uncured composition may be in a state in which the vinyl alcohol copolymer is dissolved in an aqueous solvent. The aqueous solvent refers to water, an organic solvent soluble in water, or a mixed solvent thereof. Examples of the organic solvent soluble in water include alcohols, esters, polyhydric alcohol derivatives, etc.

[0060] Among the alcohols, examples of the monohydric alcohols include methanol, ethanol, propanol, butanol, etc. Examples of the polyhydric alcohols include ethylene glycol, diethylene glycol, propylene glycol, etc.

[0061] Examples of the esters include carboxylic acid alkyl esters such as methyl-3-methoxypropionate and ethyl-3-ethoxypropionate.

[0062] Examples of the polyhydric alcohol derivatives include ethylene glycol derivatives and propylene glycol derivatives.

[0063] In order to prevent damage to the substrate to which the composition is applied, the aqueous solvent is preferably in the neutral range.

[0064] [Other ingredients] The composition may contain other components in addition to the vinyl alcohol copolymer and the aqueous solvent.

[0065] The other components are not particularly limited, and examples thereof include a laser light absorber, a plasticizer, a surfactant, and the like.

[0066] [Laser light absorber] The laser light absorbing agent is used to prevent the cured film from being thermally decomposed when the cured film is irradiated with a laser. The laser light absorbing agent is not particularly limited, and examples thereof include ultraviolet absorbing agents, pigments, dyes, etc., and is preferably soluble in an aqueous solvent.

[0067] Examples of ultraviolet absorbers that are soluble in aqueous solvents include 4,4'-dicarboxybenzophenone, benzophenone-4-carboxylic acid, 2-carboxyanthraquinone, 1,2-naphthalene dicarboxylic acid, 1,8-naphthalene dicarboxylic acid, 2,3-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid, and the like, as well as their soda salts, potassium salts, ammonium salts, and quaternary ammonium salts, 2,6-anthraquinone disulfonate sodium, 2,7-anthraquinone disulfonate sodium, and ferulic acid, of which ferulic acid is preferred.

[0068] As dyes soluble in aqueous solvents, from the viewpoint of environmental impact, food additive dyes such as Food Red No. 2, Food Red No. 40, Food Red No. 102, Food Red No. 104, Food Red No. 105, Food Red No. 106, Food Yellow NY, Food Yellow No. 4 Tartrazine, Food Yellow No. 5, Food Yellow No. 5 Sunset Yellow FCF, Food Orange AM, Food Vermilion No. 1, Food Vermilion No. 4, Food Vermilion No. 101, Food Blue No. 1, Food Blue No. 2, Food Green No. 3, Food Melon Color B, Food Egg Color No. 3, etc. are preferred.

[0069] As the dye soluble in an aqueous solvent, a water-soluble dye may be selected from among azo dyes (monoazo and polyazo dyes, metal complex azo dyes, pyrazolone azo dyes, stilbene azo dyes, thiazole azo dyes), anthraquinone dyes (anthraquinone derivatives, anthrone derivatives), indigoid dyes (indigoid derivatives, thioindigoid derivatives), phthalocyanine dyes, carbonium dyes (diphenylmethane dyes, triphenylmethane dyes, xanthene dyes, acridine dyes), quinoneimine dyes (azine dyes, oxazine dyes, thiazine dyes), methine dyes (cyanine dyes, azomethine dyes), quinoline dyes, nitroso dyes, benzoquinone and naphthoquinone dyes, naphthalimide dyes, perinone dyes, and other dyes.

[0070] [Plasticizer] The plasticizer is used to improve the water washability of the cured film, and also has the advantage of suppressing carbonization of the vinyl alcohol copolymer due to irradiation with laser light or the like.

[0071] Such plasticizers are preferably water-soluble low molecular weight compounds, such as ethylene glycol, triethylene glycol, tetraethylene glycol, ethanolamine, and glycerin, and may be used alone or in combination of two or more.

[0072] The plasticizer is used in an amount that does not cause phase separation from the water-soluble resin after application and drying. For example, the amount is preferably 75 parts by mass or less, particularly 20 parts by mass or more and 75 parts by mass or less, per 100 parts by mass of the vinyl alcohol-based copolymer.

[0073] [Surfactants] The surfactant is used to improve the coatability and further the storage stability of the composition in an uncured state. As the surfactant, any surfactant of the nonionic, cationic, anionic, or amphoteric type may be used as long as it is water-soluble.

[0074] Examples of nonionic surfactants include nonylphenol, higher alcohol, polyhydric alcohol, polyoxyalkylene glycol, polyoxyethylene alkyl ester, polyoxyethylene alkyl ether, polyoxyethylene alkylphenol ether, and polyoxyethylene sorbitan alkyl ester. Examples of cationic surfactants include quaternary ammonium salts and amine salts. Examples of anionic surfactants include alkylbenzenesulfonic acid and its salts, alkyl sulfate ester salts, methyl taurate salts, and ether sulfonates. Examples of amphoteric surfactants include imidazolinium betaine, amidopropyl betaine, and aminodipropionate salts. One or more of these may be selected. The amount of such surfactants used may be several tens to several hundreds of ppm relative to the solution.

[0075] [Physical Properties of Composition] [Solid content] The amount of solids contained in the uncured composition is not particularly limited as long as the solution has suitable coatability.

[0076] From the viewpoints of preventing dripping and the like when the composition is applied to the surface of an object and facilitating adjustment of the film thickness (thickness of the protective film) after drying, the lower limit of the solid content is preferably 3 parts by mass or more relative to 100 parts by mass of the uncured composition. Also, from the viewpoints of making the strength of the cured film appropriate and preventing foreign matter from adhering to the object when laser processing or the like is performed, the lower limit of the solid content is more preferably 5 parts by mass or more, and even more preferably 10 parts by mass or more relative to 100 parts by mass of the uncured composition.

[0077] The upper limit of the solid content varies depending on the intended use of the composition. For example, in the case of the intended use of protecting an object when performing laser processing or the like, the upper limit of the solid content is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, and even more preferably 30 parts by mass or less, relative to 100 parts by mass of the uncured composition, in order to facilitate application of the composition to the surface of the object and prevent uneven thickness and entrapment of air bubbles.

[0078] Furthermore, when the application is for protecting an object when drilling microholes in an electronic circuit board, the upper limit of the solids content is preferably 90 parts by mass or less, more preferably 80 parts by mass or less, and even more preferably 70 parts by mass or less, per 100 parts by mass of the uncured composition.

[0079] Furthermore, when the composition is intended for use in protecting an object when flattening a printed wiring board, the solid content may be 100 parts by mass (that is, the composition does not contain an aqueous solvent).

[0080] [pH] The pH of the composition is not particularly limited, but in order to prevent damage to the substrate to which the composition is applied, the lower limit of the pH is preferably 5 or more, more preferably 6 or more, and even more preferably 6.5 or more, and the upper limit of the pH is preferably 9 or less, more preferably 8 or less, and even more preferably 7.5 or less.

[0081] [viscosity] The viscosity of the composition is not particularly limited and can be appropriately selected depending on the application of the composition, etc. From the viewpoint of preventing dripping and the like when the composition is applied to the surface of an object and facilitating adjustment of the film thickness (thickness of the protective film) after drying, the lower limit of the viscosity is preferably 10 mPa·s or more, more preferably 20 mPa·s or more, and even more preferably 30 mPa·s or more.

[0082] From the viewpoint of smoothly and uniformly applying the composition to the substrate surface, the upper limit of the viscosity is preferably 800 mPa·s or less, more preferably 500 mPa·s or less, and even more preferably 300 mPa·s or less.

[0083] In this embodiment, the viscosity of the composition is determined by the viscosity at 25° C. in an uncured state measured using a B-type rotational viscometer.

[0084] [K value] In this embodiment, the K value refers to a viscosity characteristic value that correlates with molecular weight, and is calculated by applying the relative viscosity value (25° C.) measured by a B-type rotational viscometer to the following Fikentscher formula. K=(1.5logη-1) / (0.15+0.003c)+(300clogη+(c+1.5clogη) 2 ) 1 / 2 / (0.15c+0.003c 2 )

[0085] In the formula, η represents the relative viscosity of the composition to water, and c represents the vinyl alcohol copolymer concentration (%) in the composition.

[0086] In this embodiment, the K value of the composition is not particularly limited, but from the viewpoint of efficiently removing the formed protective film, it is preferably K12 to K120, more preferably K20 to K100, and even more preferably K30 to K90.

[0087] [Adhesive strength of composition] The adhesive strength of the composition can be evaluated by the tensile shear adhesive strength measured by a method in accordance with JIS K6850.

[0088] After curing, the tensile shear adhesive strength to SUS304 at 23.5°C measured according to the method in accordance with JIS K 6850 is 2N / mm 2 Above 2.5N / mm 2 This allows the cured film to have sufficient adhesive strength to the object.

[0089] [Heat resistance of the composition] In this embodiment, the heat resistance of the composition is quantified by weight loss. When the composition described in this embodiment is left at 100°C for 60 minutes, naturally cooled to 30°C, and then subjected to thermogravimetric analysis at a heating rate of 10°C / min from 30°C to 300°C in a nitrogen gas atmosphere at normal pressure, the weight loss of the composition at 300°C is 3.0% or less relative to the weight of the composition at 30°C.

[0090] The thermogravimetric analysis can be carried out using a thermal gravimetric analysis (TGA) apparatus.

[0091] [Method of producing the composition] The method for producing the composition is not particularly limited. For example, the composition is obtained by mixing a vinyl alcohol copolymer, an aqueous solvent, and other components as necessary. The mixing may be performed at room temperature or while heating. The mixing may be performed while stirring. The order of addition of each component in the composition is not particularly limited.

[0092] <Method of using the composition> The method of using the composition of this embodiment will be described below.

[0093] [For use on the processed surface of workpieces where laser processing, micro-hole processing, and flattening of printed wiring are performed] One example of the method of use is to form a protective film on the processing surface of a workpiece on which laser processing, micro-hole processing, and flattening of printed wiring are performed, thereby appropriately protecting the workpiece. This method of use includes a protective film forming step of forming a protective film on the processing surface of the workpiece, a processing step of processing the processing surface through the protective film, and a cleaning step of cleaning the processed workpiece with a cleaning solution at 80°C or higher.

[0094] [Protective film formation process] The protective film forming step is a step of coating the processing surface of a workpiece with the above-mentioned composition to form a protective film on the processing surface.

[0095] The material of the workpiece is not particularly limited as long as it can maintain sufficient adhesion between the workpiece and the protective film when the protective film is formed on the surface. Examples of the material of the workpiece include glass, synthetic quartz, resin molded products, semiconductors (e.g., semiconductor wafers), etc.

[0096] The shape of the workpiece is not particularly limited. Since the composition is liquid in an uncured state, the composition in an uncured state can be applied substantially uniformly to the surface of the workpiece even if the workpiece has irregularities.

[0097] The method for coating the composition is not particularly limited, and examples thereof include a spin coater method, a spray coater method, a screen printing method, a comma coater method, a bar coater method, a die coater method, a gravure coater method, a slit coater method, and a dip coater method.

[0098] The composition is applied in an uncured state (liquid state) to the processing surface of the workpiece, and then dried, whereby the composition is cured and a protective film can be formed on the processing surface of the workpiece. The composition can be cured at room temperature, but may be appropriately heated to dry in a shorter time, or may be irradiated with electromagnetic rays such as ultraviolet rays. When irradiating with electromagnetic rays, it is preferable that the composition contains an ultraviolet absorbing agent.

[0099] The thickness of the protective film is not particularly limited and can be appropriately selected depending on the material and shape of the workpiece, the application of the composition, and the like.

[0100] The lower limit of the thickness is not particularly limited so long as the protective film can exhibit its functions as a protective film (adhesion to the workpiece, tackiness sufficient to adhere molten or pyrolyzed products of the semiconductor substrate to the surface of the protective film, and heat resistance).

[0101] The upper limit of the thickness is not particularly limited as long as it prevents the composition from being wasted and allows easy cleaning in a cleaning step.

[0102] [Processing process] The processing step is a step of processing the processing surface through the protective film.

[0103] Examples of the processing include laser processing, fine hole processing, and flattening of printed wiring.

[0104] (Laser processing) FIG. 1 is a schematic diagram showing a state in which a first workpiece 1 is subjected to laser processing in a state in which a first protective film 2 is formed on a first processing surface 1A of the first workpiece 1.

[0105] 1(A) shows a state in which a focal point F of a laser beam L is aligned with a desired processing location of a first workpiece 1, and laser processing is performed on the first workpiece 1. The first protective film 2 irradiated with the laser beam L absorbs the laser beam L, becomes hot, and melts.

[0106] FIG. 1(B) shows a state in which first protective film 2 is melted, thereby exposing first process surface 1A that has been protected by first protective film 2.

[0107] 1(C) shows a state when the exposed first processing surface 1A is irradiated with laser light L. The first workpiece 1 absorbs the laser light L and is melted from the side of the first processing surface 1A.

[0108] Here, when the first workpiece 1 is irradiated with the laser light L, a melted material or a thermally decomposed material of the first workpiece 1 is generated. These melted materials and thermally decomposed materials are called debris D1. In this embodiment, since the first protective film 2 has adhesiveness, the debris D1 adheres to and is held on the surface of the first protective film 2. Therefore, the debris D1 does not directly adhere to the first processing surface 1A of the first workpiece 1 and does not damage the first workpiece 1.

[0109] (Micro hole processing) FIG. 2 is a schematic diagram showing the process of using a drill 50 to cut the pilot hole H in the second workpiece 11 from the second machining surface 11A of the second workpiece 11, in which the pilot hole H has been drilled, toward the opposing surface 11B opposite the second machining surface 11A, thereby performing micro-hole machining on the second workpiece 11.

[0110] A second protective film 12 is formed on the second processing surface 11A of the second workpiece 11. Here, since the composition is liquid in an uncured state, when the composition is applied to the second processing surface 11A, the composition fills not only the second processing surface 11A but also the inside of the pilot hole H of the workpiece 1. Therefore, the second protective film 12 is also formed at the location of the pilot hole H.

[0111] When the drill 50 cuts the pilot hole H in the workpiece 1, sludge such as machining chips and powder generated during cutting is generated. In this embodiment, since the second protective film 12 has adhesiveness, the debris D2 as sludge adheres to and is held on the surface of the second protective film 12 at the bottom of the hole machined by the drill 50. This prevents the debris D2 from remaining on the side surface of the pilot hole H and impairing the quality of the second workpiece 11 as a product that has been subjected to micro-hole machining.

[0112] 3 shows a state in which micro-hole drilling is performed using a drill 50 when the second processing surface 11A of the second workpiece 11 has not yet been formed with the second protective film 12. Debris D2 adheres to the inside of the pilot hole H. Once debris adheres to the inside of the pilot hole H, it is very difficult to remove the debris D2, which impairs the quality of the workpiece 1 that has been subjected to micro-hole drilling as a product.

[0113] (For use on the processed surface of a workpiece where printed wiring is to be flattened) The composition described in this embodiment can be applied to flat processing technology for printed wiring. The third workpiece includes a wiring board and a wiring portion provided on the surface of the wiring board. The third workpiece has projections and recesses corresponding to the thickness of the wiring portion, but it is preferable that the thickness of the wiring portion is as thin as possible.

[0114] First, in the above-mentioned protective film forming step, the above-mentioned composition is coated on the surface of the wiring board to form a third protective film on the surface of the wiring board. The thickness of the third protective film is not particularly limited as long as it is thicker than the thickness of the wiring part and can flatten the surface of the third workpiece after the protective film is formed.

[0115] Next, a wiring planarization device (polishing device, etc.) is applied to the surface of the third workpiece (the surface on which the wiring portion and protective film are applied) to planarize the wiring portion. A part of the wiring portion becomes processing waste due to the polishing, but since the third protective film is sticky, the processing waste adheres to the surface of the protective film as debris. Therefore, it is possible to prevent the debris from directly adhering to the surface of the wiring board or the wiring portion, which would cause deterioration of the quality of the printed wiring board.

[0116] [Cleaning process] The cleaning process is a process in which the processed workpiece is washed with a cleaning solution at 60°C or higher to remove the protective film from the processed surface. Through this process, the protective film can be easily washed away together with the debris, and the workpiece that has been subjected to laser processing, micro-hole processing, and flattening of the printed wiring can be supplied in a debris-free state.

[0117] The cleaning liquid is not particularly limited as long as it is a water-based material. The water-based material refers to water, a water-soluble organic material, or a mixture of these. Examples of the water-soluble organic material include alcohols, esters, polyhydric alcohol derivatives, etc.

[0118] Among the alcohols, examples of the monohydric alcohols include methanol, ethanol, propanol, butanol, etc. Examples of the polyhydric alcohols include ethylene glycol, diethylene glycol, propylene glycol, etc.

[0119] Examples of the esters include carboxylic acid alkyl esters such as methyl-3-methoxypropionate and ethyl-3-ethoxypropionate.

[0120] Examples of the polyhydric alcohol derivatives include ethylene glycol derivatives and propylene glycol derivatives.

[0121] To prevent damage to the workpiece after cleaning, the water-based material is preferably in the neutral range.

[0122] The temperature of the cleaning liquid is not particularly limited as long as it can easily clean the protective film together with the debris and does not cause damage such as deformation to the workpiece after cleaning. The cleaning liquid is at least 60°C, preferably at least 80°C, and more preferably at least 90°C.

[0123] In order to remove the protective film and debris more simply and cleanly, the cleaning is preferably performed by ultrasonic cleaning. More specifically, the cleaning step is preferably ultrasonic cleaning in which the object to be cleaned is placed in a cleaning tank filled with a cleaning liquid at 80° C. or higher, and high-frequency power is supplied to the inside of the cleaning tank to generate acoustic streaming in the cleaning liquid, or ultrasonic vibrations that are transmitted to the cleaning liquid and the cleaning liquid are generated in a transducer.

[0124] Fig. 4 is a schematic diagram showing ultrasonic cleaning of the first workpiece 1 after the laser processing described in Fig. 1 is performed. The cleaning device 60 includes a cleaning tank 61 filled with a cleaning liquid W, a high-frequency power supply device 62 capable of supplying high-frequency power, and a vibrator 63 connected to the high-frequency power supply device 62.

[0125] The transducer 63 is not particularly limited as long as it is a transducer that can generate ultrasonic waves in response to a supply of high-frequency power. Examples of the transducer 63 include a transducer including a piezoelectric element using a piezoelectric ceramic such as lead zirconate titanate (PZT).

[0126] First, the first workpiece 1 after laser processing is placed inside the cleaning tank 61. Then, the operator instructs the high-frequency power supply device 62 to supply high-frequency power to the transducer 63. Then, ultrasonic waves S are generated on the surface of the transducer 63, and the ultrasonic waves S are transmitted to the cleaning liquid W filling the cleaning tank 61, or generate acoustic streaming (not shown) in the cleaning liquid W, thereby removing the protective film 12 with debris D attached thereto from the surface of the first workpiece 1. By performing ultrasonic cleaning, the protective film and debris can be removed more simply and cleanly.

[0127] [Use as an adhesion prevention plate in vapor deposition processing] Another example of a method of use is to form a protective film on the surface of an adhesion prevention plate in a deposition process, thereby preventing the reaction products of the deposition reaction from accumulating on the surface of the adhesion prevention plate.

[0128] When the deposition reaction is performed, a coating called a deposition film is formed by the reaction product of the deposition reaction. If the deposition film is deposited in the chamber of the deposition device, it can have a negative effect on the vacuum properties in the case of vacuum deposition technology, and can also become a source of contamination for thin film products and affect the purity of the thin film products. In addition, it becomes difficult to remove the deposition film. Therefore, in order to prevent the deposition film from accumulating in the chamber itself, a shield is provided in the deposition device so that the deposition film is deposited on the surface of the shield. However, when the deposition process is repeated, the deposition film attached to the shield can peel off from the shield due to stress and become a source of contamination for thin film products. Therefore, it is required to provide a mechanism for easily removing the deposition film attached to the shield.

[0129] This method of use includes a protective film formation step of coating the composition described in this embodiment onto an adhesion prevention plate of a vapor deposition apparatus to form a protective film on the surface of the adhesion prevention plate, and a cleaning step of removing the deposition film and protective film formed on the surface of the adhesion prevention plate from the surface of the adhesion prevention plate.

[0130] [Protective film formation process] The protective film forming step is a step of coating an adhesion prevention plate of a vapor deposition apparatus with the composition described in this embodiment to form a protective film on the surface of the adhesion prevention plate.

[0131] The type of vapor deposition is not particularly limited, and may be physical vapor deposition (PVD) utilizing a physical reaction, or chemical vapor deposition (CVD) utilizing a chemical reaction.

[0132] The material of the adhesion prevention plate is not particularly limited as long as it can maintain sufficient adhesion between the adhesion prevention plate and the protective film when the protective film is formed on the surface. Examples of the material of the adhesion prevention plate include metals, semiconductors, non-metallic materials, etc.

[0133] The shape of the adhesion prevention plate is not particularly limited. Since the composition is liquid in an uncured state, the composition in an uncured state can be applied substantially uniformly to the surface of the adhesion prevention plate even if the adhesion prevention plate has a curved or uneven surface.

[0134] The method for coating the composition is not particularly limited, and examples thereof include a spin coater method, a spray coater method, a screen printing method, a comma coater method, a bar coater method, a die coater method, a gravure coater method, a slit coater method, and a dip coater method.

[0135] The composition in an uncured state (liquid state) is applied to the surface of the adhesion prevention plate, and then the composition is dried, whereby the composition is cured and a protective film can be formed on the surface of the adhesion prevention plate. The composition can be cured at room temperature, but may be appropriately heated to dry in a shorter time, or the composition may be irradiated with electromagnetic rays such as ultraviolet rays. When irradiating with electromagnetic rays, it is preferable that the composition contains an ultraviolet absorber.

[0136] The thickness of the protective film is not particularly limited and can be appropriately selected depending on the material and shape of the adhesion-preventing plate.

[0137] The lower limit of the thickness is not particularly limited as long as the protective film can exhibit its functions as a protective film (adhesion to the adhesion prevention plate, tackiness sufficient to attach the deposition film to the surface of the protective film, and heat resistance).

[0138] The upper limit of the thickness is not particularly limited as long as it prevents the composition from being wasted and allows easy cleaning in a cleaning step.

[0139] [Cleaning process] The cleaning process is a process in which the deposition prevention plate, on whose surface the deposition film and protective film are formed by the accumulation of reaction products of the deposition reaction, is washed with a cleaning solution at 60°C or higher to remove the deposition film and protective film from the surface of the deposition prevention plate. Through this process, the protective film can be dissolved in the cleaning solution and removed, and the deposition film can be peeled off from the deposition prevention plate while still in the film state. The peeled off deposition film can be reused as a raw material for the deposition reaction, which can contribute to improving the quality and recovery rate of recycled metals.

[0140] As described above, the cleaning liquid is not particularly limited as long as it is a water-based material, but in consideration of the quality of the deposition film recovered after cleaning and prevention of damage to the adhesion prevention plate, it is preferable that the water-based material be in the neutral range.

[0141] The temperature of the cleaning solution is not particularly limited as long as it can easily dissolve the protective film, does not affect the quality of the recovered deposition film, and does not cause damage such as deformation to the adhesion prevention plate. The cleaning solution is 60°C or higher, preferably 80°C or higher, and more preferably 90°C or higher.

[0142] In order to more simply and neatly remove the protective film and recover the deposited film, the cleaning is preferably performed by ultrasonic cleaning, which may be the same as the method described above with reference to FIG.

[0143] [Temporarily fixing the workpiece on the base] When performing surface polishing on nonmetallic materials or grinding on metallic materials, the workpiece made of nonmetallic or metallic materials is temporarily fixed on a pedestal. The composition described in this embodiment can also be used for such temporary fixing. The temporary fixing method includes a temporary fixing step of applying the composition onto a pedestal and temporarily fixing the workpiece on the pedestal, a processing step of subjecting the workpiece temporarily fixed on the pedestal to surface polishing and / or metal grinding, and a peeling step of subjecting the temporary fixing surface between the workpiece and the pedestal to hot water at 80°C or higher and peeling the workpiece from the pedestal.

[0144] Regarding fixing the workpiece on the pedestal, for example, there is a process in which the workpiece is a thin semiconductor wafer used for integrated circuits, etc. By making the thin semiconductor wafer even thinner, it is possible to realize a semiconductor with smaller size, higher integration, higher performance, lower power consumption, etc. However, a thinner thin semiconductor wafer is more fragile than a thicker semiconductor wafer, and there is a concern about the risk of damage in various processes, such as grinding, formation of through silicon vias (also called TSV), processes related to the manufacture of 2.5-dimensional / 3-dimensional stacked packages, processes related to the manufacture of power devices, processes related to the manufacture of MEMS (Micro Electro Mechanical Systems, also called MEMS), and processes related to the manufacture of LEDs. By temporarily fixing the thin semiconductor wafer on the pedestal, the risk of damage to the thin semiconductor wafer in various processes can be reduced.

[0145] The pedestal is not particularly limited as long as it is a pedestal that can support the workpiece when the workpiece is fixed on the pedestal, and may be, for example, a pedestal made of silicon, glass, and / or sapphire.

[0146] [Temporary fixing process] The temporary fixing step is a step of applying the temporary fixing composition described in this embodiment onto a base and temporarily fixing a workpiece onto the base via the temporary fixing composition.

[0147] The material of the base is not particularly limited as long as the temporary fixing composition can exert a function sufficient to temporarily fix both the workpiece and the base when the workpiece is temporarily fixed on the base, and the base may be a nonmetallic material, a metallic material, or an organic material.

[0148] The material of the workpiece is not particularly limited, as long as the temporary fixing composition can perform the function of temporarily fixing the workpiece and the base when the workpiece is temporarily fixed on the base.The workpiece may be a nonmetallic material or a metallic material.In general, if the workpiece is a nonmetallic material, it is subjected to flat surface polishing, and if the workpiece is a metallic material, it is subjected to grinding, but it is not limited thereto.

[0149] The method for applying the composition is not particularly limited. The composition in an uncured state (liquid state) is applied to the surface of the base by a known method to form a temporary fixing layer on the base, and then the non-machined surface (not shown) opposite to the processed surface of the workpiece is brought into contact with the temporary fixing layer, thereby temporarily fixing the workpiece on the base.

[0150] The thickness of the temporary fixing layer is not particularly limited, and can be appropriately selected depending on the material and shape of the base and the workpiece.

[0151] The lower limit of the thickness is not particularly limited as long as the temporary fixing layer can perform the function of temporarily fixing the base and the workpiece.

[0152] The upper limit of the thickness is not particularly limited as long as it prevents the composition from being wasted and allows easy cleaning in a cleaning step.

[0153] (Temporary bonding device) Although not essential, the method of temporary fixing is preferably a method using a temporary bonding device (also referred to as a temporary bonder, TB) capable of temporarily fixing a workpiece on a pedestal. The temporary bonding device is not particularly limited as long as it is capable of carrying out a process of applying the temporary fixing composition described in the present embodiment onto a pedestal and temporarily fixing the workpiece on the pedestal via the temporary fixing composition, and may be a temporary bonding device and / or a temporary bonding system (Temporary Bonding System) of the prior art.

[0154] Although not essential, the temporary bonding apparatus is preferably capable of performing a step of performing an alignment step of setting the positional relationship between the workpiece and the pedestal to a predetermined positional relationship, and a step of temporarily fixing the workpiece on the pedestal via a temporary fixing composition with respect to the workpiece and the pedestal arranged in the predetermined positional relationship by the alignment step. This allows the workpiece and the pedestal to be temporarily fixed in a predetermined positional relationship. Therefore, for example, the workpiece and the pedestal can be temporarily fixed in a predetermined positional relationship in which the pedestal can protect the workpiece from deformation and / or damage, and the workpiece can be protected.

[0155] [Processing process] The processing step is a step in which the workpiece temporarily fixed on the base is subjected to surface polishing and / or metal grinding.

[0156] The method of surface polishing and metal grinding is not particularly limited, and may be any known method. According to the present embodiment, since the workpiece is temporarily fixed appropriately, the nonmetallic material or metallic material can be fixed against the force in the shear direction, and the surface processing can be performed more efficiently.

[0157] [Peeling process] The peeling step is a step in which at least the temporary fixing layer formed between the workpiece and the base is subjected to an aqueous material at 80° C. or higher to peel the workpiece from the base.

[0158] The type of water-based material is not particularly limited, but in consideration of preventing damage to the base and the workpiece, the water-based material is preferably in the neutral range.

[0159] The temperature of the water-based material is not particularly limited as long as it can easily dissolve the protective film and does not cause damage such as deformation to the base and the workpiece. The water-based material is at least 60°C, preferably at least 80°C, and more preferably at least 90°C.

[0160] (Peeling device) Although not essential, the method of temporary fixing is preferably a method of performing a debonding step using a debonder (also referred to as a debonder, DB) capable of debonding the workpiece temporarily fixed on the base from the base. The debonding device is not particularly limited as long as it is capable of performing the debonding step, and may be a debonding device and / or debonding system of the prior art.

[0161] [Semiconductor product manufacturing] As an example of a specific embodiment of the method for temporary fixing using the composition of this embodiment, a procedure for manufacturing a semiconductor product by temporarily fixing a semiconductor wafer (workpiece) on a pedestal is described below. The pedestal is not particularly limited as long as it can support the semiconductor wafer, and may be, for example, silicon, glass, and / or sapphire. When the composition is an ultraviolet-curable composition that is cured by ultraviolet irradiation, the pedestal is preferably a pedestal that is transparent to ultraviolet light, exemplified by glass, sapphire, etc.

[0162] The procedure for manufacturing a semiconductor product by temporarily fixing a semiconductor wafer on a pedestal includes a temporary fixing step, a processing step, and a cleaning step.

[0163] Fig. 5 is a flow chart showing an example of a temporary fixing step in the procedure for manufacturing a semiconductor product by temporarily fixing the semiconductor wafer of this embodiment. Fig. 6 is a flow chart showing an example of a processing step in the procedure for manufacturing a semiconductor product by temporarily fixing the semiconductor wafer of this embodiment. Fig. 7 is a flow chart showing an example of a peeling step in the procedure for manufacturing a semiconductor product by temporarily fixing the semiconductor wafer of this embodiment. Hereinafter, an example of a preferable flow of the temporary fixing step will be described with reference to Figs. 5-7.

[0164] First, a temporary fixing step (steps S2-S4 in FIG. 5) is performed in which the semiconductor wafer 21, which has been subjected to the pretreatment in step S1 as necessary, is temporarily fixed to the base B.

[0165] (Step S1: Pre-processing the semiconductor wafer) Although not essential, it is preferable to perform a pretreatment step (step S1 in FIG. 5) of performing a pretreatment on the semiconductor wafer 21. There are no particular limitations on the pretreatment, so long as it is a treatment that can be performed on the semiconductor wafer.

[0166] The pretreatment may include, for example, a lithography process in which a photosensitive material is applied to the semiconductor wafer 21 and pattern exposure is performed to form a first circuit pattern C1 including a photosensitive material layer R (reference numerals R11-R14, etc. in FIG. 5) and / or a semiconductor oxide film O (reference numerals O11-O14, etc. in FIG. 5) on the temporarily fixed surface 21a of the semiconductor wafer 21. When the pretreatment includes a lithography process, the first circuit pattern C1 can be formed on the semiconductor wafer 21.

[0167] The pretreatment may include, for example, an etching process for removing an excess semiconductor oxide film O from the semiconductor wafer 21. The etching process is not particularly limited, and may be, for example, wet etching using a chemical solution, dry etching using a chemical gas and / or plasma, or the like.

[0168] Since the pretreatment includes an etching treatment, it is possible to remove excess semiconductor oxide film O from the circuit pattern C formed on the semiconductor wafer 21. As a result, it is possible to form a source and / or a drain (not shown) in a portion of the semiconductor wafer 21 that is not covered with the semiconductor oxide film O. As a result, it is possible to form a field effect transistor T (also referred to as a FET) having a source and a drain on the semiconductor wafer 21.

[0169] (Step S2: Forming a temporary fixing layer on the base using a resin composition) A temporary fixing layer forming step (step S2 in FIG. 5) is performed to form the temporary fixing layer 22 using the resin composition of this embodiment on at least one surface of the base B on which the temporary fixing layer 22 is to be formed. By performing the temporary fixing layer forming step, the temporary fixing layer 22 having adhesiveness is formed on the base B.

[0170] The temporary fixing layer forming step preferably includes a procedure of applying an uncured (liquid) composition to at least one surface of the base B on which the temporary fixing layer 22 is to be formed, and curing the applied composition. The method of applying the uncured (liquid) composition to at least one surface of the base B on which the temporary fixing layer 22 is to be formed is not particularly limited, and examples thereof include a spin coater method, a spray coater method, a screen printing method, a comma coater method, a bar coater method, a die coater method, a gravure coater method, a slit coater method, and a dip coater method.

[0171] An uncured (liquid) composition is applied to at least one surface of the base B on which the temporary fixing layer 22 is to be formed, and then the composition is dried, whereby the composition is cured and an adhesive temporary fixing layer 22 can be formed on at least one surface of the base B. The composition can be cured at room temperature, but may be appropriately heated to dry in a shorter time, or the composition may be irradiated with electromagnetic rays such as ultraviolet rays. When irradiating with electromagnetic rays, it is preferable that the composition contains an ultraviolet absorbing agent.

[0172] The thickness of the temporary fixing layer 22 is not particularly limited, and can be appropriately selected depending on one or more of the material, shape, and use of the semiconductor wafer 21, the material and shape of the base B, and the use of the semiconductor product.

[0173] The lower limit of the thickness is not particularly limited as long as the temporary fixing layer 22 can exhibit its functions as the temporary fixing layer 22 (adhesiveness to the semiconductor wafer 21 and / or base B, heat resistance).

[0174] The upper limit of the thickness is not particularly limited as long as it prevents the composition from being wasted and allows easy cleaning in a cleaning step.

[0175] (Step S3: Place the semiconductor wafer on the pedestal) An alignment step (step S3 in FIG. 5) is performed in which the semiconductor wafer 21 is placed on the pedestal B so that the surface of the pedestal B on which the temporary fixing layer 22 is located faces the temporary fixing surface 21a of the semiconductor wafer 21. By the alignment step, the pedestal B and the semiconductor wafer 21 are arranged in a predetermined positional relationship suitable for temporary fixing in which the surface of the pedestal B on which the temporary fixing layer 22 is located faces the temporary fixing surface 21a of the semiconductor wafer 21. The method for performing the alignment step is not particularly limited, and may be, for example, a method using the above-mentioned temporary bonding device.

[0176] (Step S4: Temporarily fix the base and the semiconductor wafer) A temporary bonding process (step S4 in FIG. 5) is performed in which the surface of the base B on which the temporary fixing layer 22 is located and the surface 21a of the semiconductor wafer 21 to be temporarily fixed are overlapped to temporarily fix the base B and the semiconductor wafer 21 via the temporary fixing layer 22. The temporary bonding process temporarily fixes the semiconductor wafer 21 onto the base B. This can reduce the risk of the semiconductor wafer 21 being damaged during various processing steps. The method for performing the temporary bonding process is not particularly limited, and may be, for example, a method using the above-mentioned temporary bonding device.

[0177] After the semiconductor wafer 21 is temporarily fixed to the base B by the temporary fixing step, a processing step (steps S5-S6 in FIG. 6) is performed to process the temporarily fixed semiconductor wafer 21. The processing step includes a surface polishing step (step S5) and / or a circuit forming step (step S6).

[0178] (Step S5: Flatten the semiconductor wafer) It is preferable to carry out a surface polishing step (step S5 in FIG. 6) of surface polishing the other surface 21b of the semiconductor wafer 21 opposite to the surface 21a on which the temporary fixing layer 22 of the semiconductor wafer 21 is formed. By carrying out the surface polishing step, thinner semiconductor products can be manufactured. By stacking thinner semiconductor products using 2.5-dimensional stacking packaging technology, 3-dimensional stacking packaging technology, or the like, the integration degree of the semiconductor products can be further increased.

[0179] The method for carrying out the surface polishing is not particularly limited, and may be a conventional method for surface polishing a semiconductor wafer, exemplified by a method using a polishing apparatus G.

[0180] The lower limit of the thickness of the semiconductor wafer 21 after surface polishing is not particularly limited, so long as the semiconductor wafer 21 can exhibit its functions as a semiconductor wafer (strength according to the application, etc., electrical characteristics that enable the realization of a circuit pattern according to the application, etc.).

[0181] The upper limit of the thickness of the semiconductor wafer 21 after surface polishing is not particularly limited as long as the semiconductor wafer 21 can exhibit its functions as a semiconductor wafer (such as electrical characteristics that enable a circuit pattern according to the application, etc.).

[0182] (Step S6: Forming circuits on a semiconductor wafer) It is preferable to perform a circuit formation step (step S6 in FIG. 6) of forming a second circuit pattern C2 including a photosensitive material layer R (reference numerals R21-R24, etc. in FIG. 6) and / or a semiconductor oxide film O (reference numerals O21-O24, etc. in FIG. 6) on the surface 21b of the semiconductor wafer 21 with respect to the temporarily fixed semiconductor wafer 21. By performing the circuit formation step, a semiconductor product having the second circuit pattern C2 on the surface 21b can be manufactured.

[0183] When the first circuit pattern C1 is formed on the surface Ba, a highly integrated semiconductor product can be provided in which the circuit patterns C1 and C2 are formed on the two surfaces of the semiconductor wafer 21, respectively, by the circuit formation process.

[0184] The circuit formation step is not particularly limited as long as it is a step of forming the second circuit pattern C2 on the semiconductor wafer 21, and may be, for example, a step including a lithography process and / or an etching process.

[0185] When the circuit formation process includes a lithography process, it is preferable that the circuit formation process includes a development process for removing excess photosensitive material R using a dissolving agent capable of dissolving the photosensitive material R. As a result, the excess photosensitive material R is removed, and the second circuit pattern C2 appears on the semiconductor wafer 21.

[0186] When the circuit formation process includes a development process, the circuit formation process preferably includes a bake process for heating the semiconductor wafer 21. This removes excess solvent and can improve adhesion between the semiconductor wafer 21 and a film frame and / or other semiconductor products, etc.

[0187] (Other processing steps) Although a surface polishing process and a circuit formation process have been exemplified as processes included in the processing process, the processes included in the processing process are not limited to these processes, and may include one or more of various processes related to semiconductor product manufacturing, such as a through via formation process for forming a through via (also referred to as a through silicon via, TSV), a power device formation process for forming a power device (also referred to as a power supply device) on the semiconductor wafer 21, a machine element formation process for forming machine component parts, sensors, and / or actuators, etc. on the semiconductor wafer 21, and a light emitting diode formation process for forming a light emitting diode (also referred to as an LED) on the semiconductor wafer 21.

[0188] By including a through-via formation step in the processing step, 2.5-dimensional stacked packages, 3-dimensional stacked packages, etc. using through-vias can be manufactured by temporarily fixing them with an easily removable composition, thereby making it possible to achieve both a further increase in the integration level of semiconductor products and a more efficient manufacturing process.

[0189] By including a power device formation step in the processing step, semiconductor products including higher performance power devices realized by semiconductor wafers can be manufactured by temporarily fixing them with an easily removable composition, thereby making it possible to streamline the manufacturing process for these semiconductor products.

[0190] By including a machine element forming step in the processing step, it is possible to provide a MEMS (Micro Electro Mechanical Systems, also called MEMS), which is a device in which machine element parts, sensors, and / or actuators are integrated with semiconductor circuits by microfabrication technology. This makes it possible to manufacture various micro-sized devices, such as high-frequency switches, resonators, electronic paper, microvalves, analytical chips that can be used in the biochemistry field, and various microsensors (e.g., pressure sensors, inertial sensors, microphones, etc.), by temporarily fixing them with an easily removable composition, and to provide an efficient manufacturing process for these devices.

[0191] By including a light emitting diode forming step in the processing step, semiconductor products including light emitting diodes can be manufactured by being temporarily fixed with an easily removable composition, and the manufacturing process for these semiconductor products can be made more efficient.

[0192] After the semiconductor wafer 21 is processed by the processing step, a peeling step (step S7 in FIG. 7) is performed in which the pedestal B is peeled off from the processed semiconductor wafer 21.

[0193] (Step S7: Peel off the semiconductor wafer from the pedestal) A peeling step (step S7 in FIG. 7) is performed by subjecting the temporary fixing layer 22 formed between the semiconductor wafer 21 and the pedestal B to a water-based material (also referred to as a "cleaning liquid") W at 80° C. or higher to peel the semiconductor wafer 21 from the pedestal B. By performing the peeling step, the semiconductor wafer 21 peeled off from the pedestal B can be processed and provided as a semiconductor product.

[0194] The type of cleaning liquid W is not particularly limited, but in consideration of preventing damage to the pedestal B and the semiconductor wafer 21, it is preferable that the cleaning liquid W be in the neutral range.

[0195] The temperature of the cleaning liquid W is not particularly limited as long as it can easily dissolve the temporary fixing layer 22 and does not cause damage such as deformation to the base B and the semiconductor wafer 21. The cleaning liquid W has a temperature of 60° C. or higher, preferably 80° C. or higher, and more preferably 90° C. or higher.

[0196] In a method of temporarily fixing a semiconductor wafer on a pedestal using a conventional temporary fixing composition such as a UV curable resin and / or a thermosetting resin, the temporarily fixed semiconductor wafer is peeled off from the pedestal after processing. Known methods for peeling the temporarily fixed semiconductor wafer from the pedestal include, for example, a method of mechanically peeling the semiconductor wafer and / or the pedestal by applying force to the semiconductor wafer and / or the pedestal, a method of heating the temporary fixing composition to peel it off, a method of irradiating the temporary fixing composition with energy rays (e.g., ultraviolet rays, laser, etc.) to peel it off, and a method of peeling the temporary fixing composition by using a chemical agent capable of removing the temporary fixing composition.

[0197] In the mechanical peeling method, there are concerns about the risk of damaging the thin semiconductor wafer due to the applied force, and increased costs related to equipment that can apply a force sufficient to peel the semiconductor wafer without damaging it.

[0198] In the method of peeling off by heating, there are concerns about the energy consumption for heating up to a temperature at which the adhesiveness of the temporary fixing composition is lost, the risk of damaging the thin semiconductor wafer by heat, and the increased cost for an apparatus capable of heating the semiconductor wafer without damaging it.

[0199] In the method of peeling by irradiating energy rays, there are concerns about an increase in the cost of an energy ray irradiating device, etc. In addition, in the method of peeling by irradiating energy rays, the base is limited to a (semi)transparent base that can transmit energy rays, so there are also concerns about an increase in the cost of the base.

[0200] In the method of using chemicals for stripping, there are concerns about the increased costs associated with the chemicals, etc. In particular, there is a great concern about the increased costs involved in safely treating and disposing of the chemicals after use in the stripping.

[0201] The semiconductor wafer 21 temporarily fixed to the pedestal B by the method of this embodiment can be peeled off from the pedestal B by subjecting it to a cleaning solution W at 80° C. or higher, which not only enables the semiconductor wafer 21 to be easily peeled off from the pedestal B, but also prevents the risk of damage to the semiconductor wafer and / or increased costs, etc., that may occur in a mechanical peeling method, a heating peeling method, a peeling method by irradiating energy rays, or a peeling method using chemicals. The method of this embodiment allows peeling without using chemicals, and is therefore expected to prevent environmental pollution caused by chemicals and contribute to solving environmental problems.

[0202] (Step S8: Clean the semiconductor wafer) It is preferable to perform a cleaning step (step S8 in FIG. 7) in which at least one surface 21a of the peeled semiconductor wafer 21 is cleaned with a cleaning solution W at 80° C. or higher. By performing the cleaning step, the temporary fixing layer 22 can be removed from the semiconductor wafer 21. Since the composition of the present embodiment can be cleaned with a cleaning solution W at 80° C. or higher, the temporary fixing layer 22 can be easily removed from the semiconductor wafer 21.

[0203] The type and temperature of the cleaning liquid W in the cleaning step are not particularly limited, and may be the same as the cleaning liquid W in the peeling step. EXAMPLES

[0204] The present invention will be specifically described below with reference to test examples of the present embodiment, but the present invention is not limited thereto.

[0205] <Test Example> [Sample preparation] [Preparation of Composition] The compositions described in Table 1 were prepared. [Table 1] Vinyl alcohol copolymer: A copolymer obtained by saponifying a vinyl acetate copolymer obtained by copolymerizing vinyl acetate and a (meth)acrylic monomer. Weight average molecular weight: More than 13,200

[0206] The physical properties of the composition are shown in Table 2. [Table 2]

[0207] [Formation of hardened film] A composition was applied to the entire surface of an adhesion prevention plate used in a physical vapor deposition (PVD) apparatus, and then dried to form a hardened film on the surface of the adhesion prevention plate. The shape of the adhesion prevention plate was as shown in Figure 8, with the entire surface being uneven and a hole being provided on one side of the approximate center. The material of the adhesion prevention plate was SUS304.

[0208] [Formation of Deposition Film] The deposition prevention plate with the hardened film formed on the entire surface was attached to a predetermined position in a physical vapor deposition apparatus (PVD apparatus) and a deposition process was performed. Deposition was performed using three types of materials: indium tin oxide (ITO), copper, and platinum. The reaction product of the deposition reaction was deposited on the surface of the deposition prevention plate. As a result, a deposition film was formed on the surface of the deposition prevention plate. The entire deposition prevention plate after the deposition film was formed was used as each of the samples according to Examples 1 to 3. Details of Examples 1 to 3 are shown in Table 3. [Table 3]

[0209] 〔evaluation〕 [Adhesive strength of cured film] The adhesive strength of the cured film was evaluated by the tensile shear adhesive strength to SUS304 at 23.5°C after curing, measured according to a method in accordance with JIS K 6850. The evaluation was carried out at the Saitama Prefectural Industrial Technology Center.

[0210] The test machine used was a universal material testing machine AG-1 100kN (manufactured by Shimadzu Corporation). A test piece was placed and a tensile load was applied to the test piece. The gripping distance was 112.5mm, and the test speed was 1mm / min. The test piece conformed to JIS K 6850.

[0211] The average tensile shear bond strength of five samples was 3.0N / mm 2 and the maximum value is 3.6N / mm 2 and the minimum value is 2.8N / mm 2 It was.

[0212] [Heat resistance of cured film] The heat resistance of the cured film was evaluated by thermogravimetric analysis (TGA). The composition obtained in the test example was heated at 100°C for 60 minutes to obtain a cured product. The obtained cured product was naturally cooled to 30°C, and then the weight loss of the composition was measured using a simultaneous differential thermal and thermogravimetric analyzer (device name: TGA Q500, manufactured by TA Instruments Japan Co., Ltd.) under conditions of normal pressure 4N5 N2 gas, flow rate 60ml / min, temperature range 30°C to 800°C, and heating rate 10°C / min. The results are shown in Figure 9.

[0213] The horizontal axis of Fig. 9 is temperature, the vertical axis on the left is weight (unit: %), and the vertical axis on the right is differential weight (unit: % / °C). In Fig. 9, the solid line shows the relationship between temperature and weight, and the dashed line shows the relationship between temperature and differential weight.

[0214] 9, it was confirmed that the weight loss of the composition at 303.1° C. was 1.000% of the weight of the composition at 30° C., and the weight loss of the composition at 350.65° C. was 3.000% of the weight of the composition at 30° C. From FIG. 9, it can be said that the cured film used in this test example has sufficient heat resistance required for surface protection in laser processing, micro-hole processing, flattening of printed wiring, deposition processing, etc.

[0215] [Ease of peeling when exposed to warm water] Warm water at 80°C was poured into cleaning tank 61 shown in Fig. 4, and the samples according to Examples 1 to 3 were immersed in the warm water. Then, high-frequency power was supplied from high-frequency power supply device 62 to transducer 63. In each of Examples 1 to 3, the deposition film peeled off from the adhesion prevention plate 5 minutes after the high-frequency power was supplied, and the deposition film maintained its film state. Furthermore, no adhesive was left on either the deposition film or the adhesion prevention plate. [Explanation of symbols]

[0216] 1 1st workpiece 1A 1st machining surface 2 1st protective film 11 Second workpiece 11A 2nd machining surface 11B Opposite surface 12 Second protective film 21 Semiconductor Wafers 21a Temporary fixing surface 21b The other side 22 Temporary fixing layer 50 Drill 60 Cleaning Equipment 61 Cleaning tank 62 High frequency power supply device 63 Transducer B Pedestal C1 First circuit pattern C2 First circuit pattern D1 Debris D2 Debris F Focus point G polishing equipment H pilot hole L Laser light O Semiconductor oxide film R Photosensitive material layer S Ultrasonic W cleaning solution

Claims

[Claim 1] a temporary fixing step of applying a temporary fixing composition onto a base and temporarily fixing a workpiece onto the base via the temporary fixing composition; a processing step of subjecting the workpiece temporarily fixed on the pedestal to surface polishing and / or metal grinding; a peeling step of exposing at least a temporary fixing surface between the workpiece and the base to a water-based material at 80° C. or higher, and peeling the workpiece from the base, The temporary fixing composition contains a vinyl alcohol-based copolymer obtained by saponifying a vinyl acetate-based copolymer obtained by copolymerizing vinyl acetate and a (meth)acrylic monomer, After curing, the tensile shear adhesive strength to SUS304 at 23.5°C measured according to a method in accordance with JIS K 6850 is 2 N / mm ２ That's all. a method for using the temporary fixing composition, in which, when the temporary fixing composition is heated at 100° C. for 60 minutes, naturally cooled to 30° C., and then subjected to thermogravimetric analysis at a temperature increase rate of 10° C. / min from 30° C. to 300° C. in a nitrogen gas atmosphere under normal pressure, a weight loss of the temporary fixing composition at 300° C. is 3.0% or less relative to the weight of the temporary fixing composition at 30° C.

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