Parts processing method

Abstract

To provide a member processing method which can prevent damage etc. of a processed body (member etc.) while including peeling of a hard substrate from the processed body.SOLUTION: A member processing method of the invention includes: a lamination step in which a hard substrate, an ultraviolet absorption layer, and a processed body are laminated in a written order; a processing step in which the processed body is processed after the lamination step, and a peeling step in which ultraviolet light is radiated to the ultraviolet absorption layer to peel the hard substrate from the processed body after the processing step.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a member processing method.

Background Art

[0002] In the processing of electronic components (members), considering the handling property between processes, there are cases where a member is sandwiched between a pair of substrates and the member is processed (for example, Patent Document 1). For example, in the process of thermocompression bonding a member to a terminal on a wiring circuit board, in a state where the member is temporarily placed on the terminal on the wiring circuit board, a steel plate is stacked thereon through a double-sided adhesive sheet, and the member is held while being pressurized, and heat treatment is performed to fix the terminal. Then, after the heat treatment, the pressure is released, the steel plate is peeled off from the member, and the member is fixed to the terminal on the wiring circuit board.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a process of sandwiching a member between a pair of substrates (the first substrate and the second substrate) and then peeling off one substrate (the second substrate) from the member, such as in the process of thermocompression bonding a member on the above wiring circuit board, when the peeled second substrate is hard, since the second substrate (hard substrate) is difficult to deform, the second substrate (hard substrate) will be separated in the vertical direction. Then, there are problems such as a load being applied to the member and the member being damaged, or the member being undesirably detached from the first substrate.

[0005] The present invention was made to solve the above-mentioned conventional problems, and its objective is to provide a method for processing a component that includes peeling a hard substrate from the workpiece (component, etc.) while preventing damage to the workpiece. [Means for solving the problem]

[0006] The present invention provides a method for processing a component, comprising a lamination step of laminating a hard substrate, an ultraviolet absorbing layer, and a workpiece in that order; a processing step of processing the workpiece; and a peeling step of irradiating the ultraviolet absorbing layer with ultraviolet light to peel the hard substrate from the workpiece. In one embodiment, the workpiece includes another hard substrate and a member disposed on at least one side of the hard substrate. In one embodiment, the workpiece is a semiconductor wafer. In one embodiment, the rigid substrate is light-transmitting. In one embodiment, the ultraviolet absorbing layer is adhesive. In one embodiment, the ultraviolet absorbing layer includes an active energy ray curing adhesive. In one embodiment, the ultraviolet absorbing layer includes an ultraviolet absorber. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a method for processing a component that includes peeling a hard substrate from a workpiece (component, etc.) while preventing damage to the workpiece. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram illustrating a method for processing a component according to one embodiment of the present invention. [Modes for carrying out the invention]

[0009] A. Overview of component processing methods Figure 1 is a schematic diagram illustrating a method for processing a component according to one embodiment of the present invention. The method for processing a component according to the present invention includes (i) a step of laminating a hard substrate 10, an ultraviolet absorption layer 20, and a workpiece 30 in this order (hereinafter also referred to as the lamination step), (ii) a step of processing the workpiece 30 thereafter (processing step), and (iii) a step of irradiating the ultraviolet absorption layer 20 with ultraviolet light to peel the hard substrate 10 from the workpiece 30 (peeling step).

[0010] B.Lamination process As described above, the lamination process involves laminating the rigid substrate 10, the ultraviolet absorption layer 20, and the workpiece 30 in this order. In one embodiment, the ultraviolet absorption layer is adhesive. The workpiece 30 in the illustrated example comprises another rigid substrate 31 and a member 32 disposed on one side of the other rigid substrate 31.

[0011] In one embodiment, a substrate 21 and an adhesive layer 22 may be further arranged between the UV-absorbing layer 20 and the workpiece 30. The UV-absorbing layer 20, the substrate 21, and the adhesive layer 22 may be arranged in this order. In one embodiment, the laminate composed of the UV-absorbing layer 20, the substrate 21, and the adhesive layer 22 may be a double-sided adhesive sheet A.

[0012] In another embodiment, the rigid substrate and the workpiece may be arranged with an ultraviolet absorbing layer in between. More specifically, the rigid substrate is placed directly on one side of the ultraviolet absorbing layer, and the workpiece is placed directly on the other side of the ultraviolet absorbing layer.

[0013] B-1. Rigid substrate The above-mentioned rigid substrate refers to a molded article on a plate with a flexural modulus of 1 GPa or more. The flexural modulus can be measured by a four-point bending test in accordance with JIS K7171 or JIS R1602, depending on the material constituting the rigid substrate.

[0014] As the material constituting the rigid substrate, any suitable material can be used. Examples of the rigid substrate include a glass substrate, a metal substrate, a silicon substrate, a sapphire substrate, a plastic substrate, and the like.

[0015] Preferably, the rigid substrate has light transmissivity. The ultraviolet ray (wavelength 360 nm) transmittance of the rigid substrate is preferably 70% or more, more preferably 80% to 99.9%. If the rigid substrate has light transmissivity, peeling in the peeling step can be preferably caused.

[0016] B-2. Ultraviolet Absorbing Layer The ultraviolet absorbing layer can be a layer that has adhesiveness initially (i.e., before ultraviolet irradiation) and shows peelability with a decrease in adhesive force after ultraviolet irradiation. In one embodiment, the ultraviolet absorbing layer can be a layer in which the adhesive force decreases partially by partial ultraviolet irradiation (for example, UV laser light irradiation).

[0017] In one embodiment, the ultraviolet absorbing layer contains an ultraviolet absorber. Preferably, the ultraviolet absorbing layer further contains an adhesive. Examples of the adhesive include a pressure-sensitive adhesive and an active energy ray-curable adhesive.

[0018] When the ultraviolet absorbing layer contains an ultraviolet absorber, peeling of the adherend by UV laser light irradiation becomes possible. More specifically, by irradiating the ultraviolet absorbing layer with UV laser light, the gas generated by the decomposition of the ultraviolet absorber and / or the gas generated by the decomposition of the ultraviolet absorbing layer due to the heat generated by the ultraviolet absorber causes deformation in the ultraviolet absorbing layer. As a result, peelability appears in the portion irradiated with the UV laser light.

[0019] Furthermore, if the ultraviolet absorption layer contains an active energy ray-curable adhesive, the adhesive strength of the entire ultraviolet absorption layer can be reduced by irradiating it with active energy rays. In one embodiment, the entire ultraviolet absorption layer is irradiated with active energy rays to reduce its adhesive strength, and then irradiated with laser light as described above. This significantly prevents adhesive residue after peeling and re-adhesion to hard substrates, and is advantageous from the viewpoint of preventing contamination compared to conventional methods using varnish, for example. Examples of active energy rays include gamma rays, ultraviolet rays, visible light, infrared rays (heat rays), radio waves, alpha rays, beta rays, electron beams, plasma streams, ionization rays, and particle beams. Ultraviolet rays are preferred.

[0020] The light transmittance of the UV-absorbing layer at a wavelength of 360 nm is preferably 50% or less. By lowering this light transmittance, the laser output during peeling can be reduced. The light transmittance of the UV-absorbing layer at a wavelength of 355 nm is preferably 30% or less. Within this range, the above effect becomes more pronounced. Furthermore, the light transmittance of the UV-absorbing layer at a wavelength of 380 nm is preferably 30% or more, and more preferably 50% or more.

[0021] The initial adhesive strength at 23°C when the UV-absorbing layer is attached to a stainless steel plate is preferably 0.1N / 20mm to 20N / 20mm, and more preferably 0.5N / 20mm to 15N / 20mm. Within this range, a UV-absorbing layer capable of holding the workpiece well can be formed. The adhesive strength is measured in accordance with JIS Z 0237:2000. Specifically, the UV-absorbing layer is attached to a stainless steel plate (arithmetic mean surface roughness Ra: 50±25nm) by one back-and-forth motion of a 2kg roller, left at 23°C for 30 minutes, and then the UV-absorbing layer is peeled off and measured under conditions of a peeling angle of 180° and a peeling speed (tensile speed) of 300mm / min. The adhesive strength of the UV-absorbing layer changes with irradiation of active energy rays and laser light, but in this specification, "initial adhesive strength" means the adhesive strength before irradiation with active energy rays and laser light.

[0022] In one embodiment, an ultraviolet absorbing layer is attached to a stainless steel plate, and the UV level is 460 mJ / cm². 2 The adhesive strength at 23°C after irradiation with ultraviolet light is preferably 0.01 N / 20 mm to 2 N / 20 mm, and more preferably 0.02 N / 20 mm to 1 N / 20 mm. Within this range, a UV-absorbing layer that can be peeled off with minimal adhesive residue can be formed. The above UV irradiation is performed, for example, using an ultraviolet irradiation device (manufactured by Nitto Seiki Co., Ltd., product name "UM-810") with ultraviolet light from a high-pressure mercury lamp (characteristic wavelength: 365 nm, integrated light intensity: 460 mJ / cm²). 2 Irradiation energy: 70W / cm² 2 This is performed by irradiating the ultraviolet absorption layer with an irradiation time of 6.6 seconds.

[0023] The thickness of the ultraviolet absorption layer is preferably 50 μm or less. Within this range, it is possible to lower the laser power during peeling. More preferably, the thickness of the ultraviolet absorption layer is 40 μm or less, even more preferably 30 μm or less, and most preferably 1 μm to 30 μm. Within this range, the above effects become more pronounced.

[0024] • UV absorbers: Any suitable UV absorber can be used as the UV absorber, as long as it is a compound that absorbs ultraviolet light (e.g., wavelength 355 nm). Examples of UV absorbers include benzotriazole-based UV absorbers, benzophenone-based UV absorbers, triazine-based UV absorbers, salicylate-based UV absorbers, and cyanoacrylate-based UV absorbers. Among these, triazine-based UV absorbers or benzotriazole-based UV absorbers are preferred, and triazine-based UV absorbers are particularly preferred. In particular, when an acrylic adhesive is used as adhesive A, triazine-based UV absorbers can be preferred because of their high compatibility with the base polymer of the acrylic adhesive. Triazine-based UV absorbers are more preferably composed of compounds having hydroxyl groups, and are particularly preferably UV absorbers composed of hydroxyphenyltriazine compounds (hydroxyphenyltriazine-based UV absorbers).

[0025] Examples of hydroxyphenyltriazine-based UV absorbers include the reaction product of 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine-2-yl)-5-hydroxyphenyl and [(C10-C16 (mainly C12-C13) alkyloxy)methyl]oxirane (trade name "TINUVIN 400", manufactured by BASF), 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine-2-yl]-5-[3-(dodecyloxy)-2-hydroxypropoxy]phenol), and the reaction product of 2-(2,4-dihydroxyphenyl)-4,6-bis-(2,4-dimethylphenyl)-1,3,5-triazine and (2-ethylhexyl)-glycidic acid ester (trade name "TINUVIN 400"). 405 (manufactured by BASF), 2,4-bis(2-hydroxy-4-butoxyphenyl)-6-(2,4-dibutoxyphenyl)-1,3,5-triazine (product name "TINUVIN 460", manufactured by BASF), 2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-[(hexyl)oxy]-phenol (product name "TINUVIN 1577", manufactured by BASF), 2-(4,6-diphenyl-1,3,5-triazine-2-yl)-5-[2-(2-ethylhexanoyloxy)ethoxy]-phenol (product name "ADEKA Stab LA-46", manufactured by ADEKA Corporation), 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine (product name "TINUVIN Examples include "479" (manufactured by BASF) and "TINUVIN 477" (a product name by BASF).

[0026] Examples of benzotriazole-based UV absorbers (benzotriazole compounds) include 2-(2-hydroxy-5-tert-butylphenyl)-2H-benzotriazole (trade name "TINUVIN PS", manufactured by BASF), benzenepropanoic acid and ester compounds of 3-(2H-benzotriazole-2-yl)-5-(1,1-dimethylethyl)-4-hydroxy(C7-9 side chain and linear alkyl) (trade name "TINUVIN 384-2", manufactured by BASF), octyl 3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazole-2-yl)phenyl]propionate and a mixture of 2-ethylhexyl-3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazole-2-yl)phenyl]propionate (trade name "TINUVIN Reaction product of methyl 3-(3-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol (product name "TINUVIN 900", manufactured by BASF), 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol (product name "TINUVIN 928", manufactured by BASF), reaction product of methyl 3-(3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl)propionate / polyethylene glycol 300 (product name "TINUVIN 1130", manufactured by BASF), 2-(2H-benzotriazol-2-yl)-p-cresol (product name "TINUVIN P (manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol (trade name "TINUVIN 234", manufactured by BASF), 2-[5-chloro-2H-benzotriazol-2-yl]-4-methyl-6-(tert-butyl)phenol (trade name "TINUVIN 326", manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol (trade name "TINUVIN 328", manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-Tetramethylbutyl)phenol (trade name "TINUVIN 329", manufactured by BASF), 2,2'-Methylenebis[6-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol] (trade name "TINUVIN 360", manufactured by BASF), reaction product of methyl 3-(3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl)propionate and polyethylene glycol 300 (trade name "TINUVIN 213", manufactured by BASF), 2-(2H-benzotriazol-2-yl)-6-dodecyl-4-methylphenol (trade name "TINUVIN 571", manufactured by BASF), 2-[2-hydroxy-3-(3,4,5,6-tetrahydrophthalimidomethyl)-5-methylphenyl]benzotriazole (trade name "Sumisorb" 250", manufactured by Sumitomo Chemical Co., Ltd., 2-(3-tert-butyl-2-hydroxy-5-methylphenyl)-5-chloro-2H-benzotriazole (product name "SEESORB 703", manufactured by Cipro Chemical Co., Ltd.), 2-(2H-benzotriazol-2-yl)-4-methyl-6-(3,4,5,6-tetrahydrophthalimidylmethyl)phenol (product name "SEESORB 706", manufactured by Cipro Chemical Co., Ltd.), 2-(4-benzoyloxy-2-hydroxyphenyl)-5-chloro-2H-benzotriazole (product name "SEESORB 7012BA", manufactured by Cipro Chemical Co., Ltd.), 2-tert-butyl-6-(5-chloro-2H-benzotriazol-2-yl)-4-methylphenol (product name "SEESORB 706", manufactured by Cipro Chemical Co., Ltd.) Examples include 73 (manufactured by Chemipro Chemical Co., Ltd.), 2,2'-methylenebis[6-(2H-benzotriazole-2-yl)-4-tert-octylphenol] (product name "ADEKA Stab LA-31", manufactured by ADEKA Corporation), 2-(2H-benzotriazole-2-yl)-p-cellulose (product name "ADEKA Stab LA-32", manufactured by ADEKA Corporation), and 2-(5-chloro-2H-benzotriazole-2-yl)-6-tert-butyl-4-methylphenol (product name "ADEKA Stab LA-36", manufactured by ADEKA Corporation).

[0027] The above-mentioned ultraviolet absorber may be a dye or a pigment. Examples of pigments include azo, phthalocyanine, anthraquinone, lake, perylene, perinone, quinacridone, thioindigo, dioxandine, isoindolinone, and quinophthalone pigments. Examples of dyes include azo, phthalocyanine, anthraquinone, carbonyl, indigo, quinoneimine, methine, quinoline, and nitro dyes.

[0028] The molecular weight of the compound constituting the above-mentioned ultraviolet absorber is preferably 100 to 1500, more preferably 200 to 1200, and even more preferably 200 to 1000. Within this range, an ultraviolet absorbing layer capable of forming a better deformable portion can be formed by laser irradiation.

[0029] The maximum absorption wavelength of the above-mentioned ultraviolet absorber is preferably 300 nm to 450 nm, more preferably 320 nm to 400 nm, and even more preferably 330 nm to 380 nm. The difference between the maximum absorption wavelength of the ultraviolet absorber and the maximum absorption wavelength of the above-mentioned photopolymerization initiator is preferably 10 nm or more, and more preferably 25 nm or more.

[0030] The 5% weight loss temperature of the above-mentioned UV absorber is preferably 350°C or lower, and more preferably 330°C or lower. The lower limit of the 5% weight loss temperature of the UV absorber is, for example, 100°C. Within this range, a UV-absorbing layer capable of forming a better deformation zone can be formed by laser irradiation. The 5% weight loss temperature of the UV absorber refers to the temperature at which the weight of the UV absorber decreases by 5% by weight compared to its weight before heating. The 5% weight loss temperature is measured using a differential thermal analyzer under measurement conditions of heating temperature of 10°C / min, air atmosphere, and flow rate of 25 ml / min.

[0031] The content ratio of the above-mentioned ultraviolet absorber is preferably 1 to 50 parts by weight, and more preferably 5 to 20 parts by weight, per 100 parts by weight of the base polymer in the ultraviolet absorption layer. Within this range, when the adhesive strength of the entire ultraviolet absorption layer is goodly reduced by irradiation with active energy rays, the curing of the ultraviolet absorption layer proceeds well, and an ultraviolet absorption layer exhibiting good peelability by laser irradiation can be formed.

[0032] • Active energy ray curing adhesive: In one embodiment, an active energy ray-curable adhesive (A1) is used, comprising a base polymer that serves as a matrix and an active energy ray-reactive compound (monomer or oligomer) that can bond to the base polymer. In another embodiment, an active energy ray-curable adhesive (A2) is used, comprising an active energy ray-reactive polymer as the base polymer. Preferably, the base polymer has a functional group that can react with a photopolymerization initiator. Examples of such functional groups include hydroxyl groups and carboxyl groups.

[0033] Examples of base polymers used in the above-mentioned adhesive (A1) include rubber-based polymers such as natural rubber, polyisobutylene rubber, styrene-butadiene rubber, styrene-isoprene-styrene block copolymer rubber, recycled rubber, butyl rubber, polyisobutylene rubber, and nitrile rubber (NBR); silicone-based polymers; and acrylic-based polymers. These polymers may be used individually or in combination of two or more. Among these, acrylic-based polymers are particularly preferred.

[0034] Examples of acrylic polymers include monopolymers or copolymers of hydrocarbon group-containing (meth)acrylic acid esters such as alkyl (meth)acrylates, cycloalkyl (meth)acrylates, and aryl (meth)acrylates; and copolymers of the hydrocarbon group-containing (meth)acrylic acid ester with other copolymerizable monomers. Examples of alkyl (meth)acrylates include methyl esters, ethyl esters, propyl esters, isopropyl esters, butyl esters, isobutyl esters, s-butyl esters, t-butyl esters, pentyl esters, isopentyl esters, hexyl esters, heptyl esters, octyl esters, 2-ethylhexyl esters, isooctyl esters, nonyl esters, decyl esters, isodecyl esters, undecyl esters, dodecyl esters, i.e., lauryl esters, tridecyl esters, tetradecyl esters, hexadecyl esters, octadecyl esters, and eicosyl esters. Examples of cycloalkyl (meth)acrylates include cyclopentyl esters and cyclohexyl esters of (meth)acrylic acid. Examples of (meth)acrylate aryl esters include phenyl (meth)acrylate and benzyl (meth)acrylate. The content of the constituent units derived from the hydrocarbon group-containing (meth)acrylate is preferably 40 parts by weight or more, and more preferably 60 parts by weight or more, per 100 parts by weight of the base polymer.

[0035] Other copolymerizable monomers include, for example, carboxyl group-containing monomers, acid anhydride monomers, hydroxyl group-containing monomers, glycidyl group-containing monomers, sulfonic acid group-containing monomers, phosphate group-containing monomers, acrylamide, and functional group-containing monomers such as acrylonitrile. Examples of carboxyl group-containing monomers include acrylic acid, methacrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. Examples of acid anhydride monomers include maleic anhydride and itaconic anhydride. Examples of hydroxyl group-containing monomers include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, and (4-hydroxymethylcyclohexyl)methyl (meth)acrylate. Examples of glycidyl group-containing monomers include glycidyl (meth)acrylate and methylglycidyl (meth)acrylate. Examples of sulfonic acid group-containing monomers include styrene sulfonic acid, allyl sulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, (meth)acrylamidepropanesulfonic acid, sulfopropyl (meth)acrylate, and (meth)acryloyloxynaphthalenesulfonic acid. An example of a phosphate group-containing monomer is 2-hydroxyethyl acryloyl phosphate. An example of an acrylamide is N-acryloylmorpholine. These may be used individually or in combination of two or more. The content of the constituent units derived from the above copolymerizable monomers is preferably 60 parts by weight or less, and more preferably 40 parts by weight or less, per 100 parts by weight of the base polymer.

[0036] Acrylic polymers may contain structural units derived from polyfunctional monomers to form crosslinked structures within their polymer backbone. Examples of polyfunctional monomers include hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy(meth)acrylate (i.e., polyglycidyl(meth)acrylate), polyester(meth)acrylate, and urethane(meth)acrylate. These may be used individually or in combination of two or more. The content of the structural units derived from the above polyfunctional monomers is preferably 40 parts by weight or less, and more preferably 30 parts by weight or less, per 100 parts by weight of the base polymer.

[0037] The weight-average molecular weight of the above acrylic polymer is preferably 100,000 to 3,000,000, and more preferably 200,000 to 2,000,000. The weight-average molecular weight can be measured by GPC (solvent: THF).

[0038] Examples of the active energy ray-reactive compounds that can be used in the above adhesive (A1) include photoreactive monomers or oligomers having a functional group with polymerizable carbon-carbon multiple bonds, such as an acryloyl group, a methacryloyl group, a vinyl group, an allyl group, or an acetylene group. Specific examples of the photoreactive monomer include esters of (meth)acrylic acid with polyhydric alcohols such as trimethylolpropane tri(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate; polyfunctional urethane (meth)acrylate; epoxy (meth)acrylate; and oligoester (meth)acrylate. In addition, monomers such as methacryloisocyanate, 2-methacryloyloxyethyl isocyanate (2-isocyanatoethyl methacrylate), and m-isopropenyl-α,α-dimethylbenzyl isocyanate may also be used. Specific examples of photoreactive oligomers include dimers to pentamers of the above-mentioned monomers. The molecular weight of the photoreactive oligomer is preferably 100 to 3000.

[0039] Furthermore, monomers such as epoxidized butadiene, glycidyl methacrylate, acrylamide, and vinylsiloxane, or oligomers composed of such monomers, may be used as the active energy ray-reactive compound.

[0040] Furthermore, as the active energy ray-reactive compound, a mixture of organic salts such as onium salts and compounds having multiple heterocycles in their molecule may be used. In this mixture, irradiation with active energy rays (e.g., ultraviolet rays, electron beams) can cause the organic salts to cleave and generate ions, which act as initiating species to trigger ring-opening reactions of the heterocycles and form a three-dimensional network structure. Examples of the organic salts include iodonium salts, phosphonium salts, antimonium salts, sulfonium salts, and borate salts. Examples of heterocycles in the compounds having multiple heterocycles in their molecule include oxiranes, oxetanes, oxolanes, thirans, and aziridines.

[0041] In the above adhesive (A1), the content ratio of the active energy ray-reactive compound is preferably 0.1 to 500 parts by weight, more preferably 5 to 300 parts by weight, and even more preferably 40 to 150 parts by weight, per 100 parts by weight of the base polymer.

[0042] Examples of active energy ray-reactive polymers (base polymers) included in the above adhesive (A2) include polymers having functional groups with carbon-carbon multiple bonds, such as acryloyl groups, methacryloyl groups, vinyl groups, allyl groups, and acetylene groups. Specific examples of active energy ray-reactive polymers include polymers composed of polyfunctional (meth)acrylates; photocationic polymers; cinnamoyl group-containing polymers such as polyvinyl cinnamate; diazotized amino novolac resins; polyacrylamide; and the like.

[0043] In one embodiment, an active energy ray reactive polymer is used, which is constructed by introducing an active energy ray polymerizable carbon-carbon double bond into the side chains, main chain, and / or main chain terminals of the above-mentioned acrylic polymer. As a method for introducing a radiation-polymerizable carbon-carbon double bond into an acrylic polymer, for example, an acrylic polymer is obtained by copolymerizing raw material monomers containing a monomer having a predetermined functional group (first functional group), and then a compound having a predetermined functional group (second functional group) that can react and bond with the first functional group and a radiation-polymerizable carbon-carbon double bond is subjected to a condensation or addition reaction with the acrylic polymer while maintaining the radiation polymerizability of the carbon-carbon double bond.

[0044] Examples of combinations of the first and second functional groups include carboxyl group and epoxy group, epoxy group and carboxyl group, carboxyl group and aziridyl group, aziridyl group and carboxyl group, hydroxyl group and isocyanate group, and isocyanate group and hydroxyl group. Of these combinations, from the viewpoint of ease of reaction tracking, the combination of hydroxyl group and isocyanate group, or the combination of isocyanate group and hydroxyl group is preferred. Furthermore, since it is technically difficult to produce polymers having highly reactive isocyanate groups, from the viewpoint of ease of production or availability of acrylic polymers, it is more preferable that the first functional group on the acrylic polymer side is a hydroxyl group and the second functional group is an isocyanate group. In this case, examples of isocyanate compounds having both a radiation-polymerizable carbon-carbon double bond and an isocyanate group as the second functional group include methacryloyl isocyanate, 2-methacryloyloxyethyl isocyanate, and m-isopropenyl-α,α-dimethylbenzyl isocyanate. Furthermore, as the acrylic polymer having the first functional group, it is preferable that it contains structural units derived from the above-mentioned hydroxyl group-containing monomer, and it is also preferable that it contains structural units derived from ether compounds such as 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, and diethylene glycol monovinyl ether.

[0045] The above adhesive (A2) may further contain the above-mentioned active energy ray-reactive compound (monomer or oligomer).

[0046] The above-mentioned active energy ray curing adhesive may contain a photopolymerization initiator.

[0047] Any suitable initiator can be used as a photopolymerization initiator. Examples of photopolymerization initiators include α-ketol compounds such as 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone, α-hydroxy-α,α'-dimethylacetophenone, 2-methyl-2-hydroxypropiophenone, and 1-hydroxycyclohexylphenyl ketone; acetophenone compounds such as methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, and 2-methyl-1-[4-(methylthio)-phenyl]-2-morpholinopropane-1; benzoin ether compounds such as benzoin ethyl ether, benzoin isopropyl ether, and anisoin methyl ether; and ketal compounds such as benzyldimethyl ketal. Examples include aromatic sulfonyl chloride compounds such as 2-naphthalenesulfonyl chloride; photoactive oxime compounds such as 1-phenone-1,1-propanedione-2-(o-ethoxycarbonyl)oxime; benzophenone compounds such as benzophenone, benzoylbenzoic acid, and 3,3'-dimethyl-4-methoxybenzophenone; thioxanthone compounds such as thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, and 2,4-diisopropylthioxanthone; camphorquinone; halogenated ketones; acylphosphinoxides; and acylphosphonates. The amount of photopolymerization initiator used can be set to any appropriate amount.

[0048] In one embodiment, a photopolymerization initiator having a maximum absorption wavelength in the range of 400 nm or less (preferably 380 nm or less, more preferably 340 nm or less) is used. When such a photopolymerization initiator is used, when the adhesive strength of the entire ultraviolet absorption layer is reduced by irradiation with active energy rays, the curing reaction of the adhesive occurs favorably, and an ultraviolet absorption layer with particularly little adhesive residue can be formed.

[0049] Commercially available products may be used as the above-mentioned photopolymerization initiators. For example, examples of photopolymerization initiators having a maximum absorption wavelength in the range of 400 nm or less include BASF products such as "Irgacure 127", "Irgacure 369", "Irgacure 369E", "Irgacure 379", "Irgacure 379EG", "Irgacure 819", "Irgacure TOP", "Irgacure 784", and "Irgacure OXE01".

[0050] In one embodiment, the active energy ray curable adhesive may include a photosensitizer.

[0051] In one embodiment, the photosensitizer may be used in combination with the photopolymerization initiator. The photosensitizer can generate radicals from the photopolymerization initiator by transferring the energy it obtains from absorbing light to the photopolymerization initiator, thus enabling polymerization to proceed with long-wavelength light where the photopolymerization initiator itself does not have an absorption peak. Therefore, by including the photosensitizer, it is possible to increase the difference between the absorption wavelength of the ultraviolet absorber and the wavelength at which radicals can be generated from the photopolymerization initiator. As a result, the photopolymerization of the ultraviolet absorption layer and the peeling by the ultraviolet absorber can be carried out without mutual interference. In one embodiment, 2,2-dimethoxy-1,2-diphenylethane-1-one (e.g., BASF product name "Irgacure 651") as a photopolymerization initiator is used in combination with the photosensitizer. Examples of such photosensitizers include "UVS-581" manufactured by Kawasaki Chemical Industries, Ltd., and 9,10-diethoxyanthracene (for example, "UVS1101" manufactured by Kawasaki Chemical Industries, Ltd.).

[0052] Other examples of the above-mentioned photosensitizers include 9,10-dibutoxyanthracene (e.g., Kawasaki Chemical Industries, Ltd., trade name "UVS-1331"), 2-isopropylthioxanthone, benzophenone, thioxanthone derivatives, and 4,4'-bis(dimethylamino)benzophenone. Examples of thioxanthone derivatives include ethoxycarbonylthioxanthone and isopropylthioxanthone.

[0053] The content ratio of the above-mentioned photosensitizer is preferably 0.01 to 2 parts by weight, and more preferably 0.5 to 2 parts by weight, per 100 parts by weight of the base polymer.

[0054] Preferably, the above-mentioned active energy ray curing adhesive contains a crosslinking agent. Examples of crosslinking agents include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, oxazoline-based crosslinking agents, aziridine-based crosslinking agents, melamine-based crosslinking agents, peroxide-based crosslinking agents, urea-based crosslinking agents, metal alkoxide-based crosslinking agents, metal chelate-based crosslinking agents, metal salt-based crosslinking agents, carbodiimide-based crosslinking agents, amine-based crosslinking agents, and the like.

[0055] The content ratio of the above crosslinking agent is preferably 0.5 to 10 parts by weight, and more preferably 1 to 8 parts by weight, per 100 parts by weight of the base polymer of the adhesive.

[0056] In one embodiment, an isocyanate-based crosslinking agent is preferably used. Isocyanate-based crosslinking agents are preferred because they can react with a variety of functional groups. Specific examples of the above-mentioned isocyanate-based crosslinking agents include: lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; alicyclic isocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate, and isophorone diisocyanate; aromatic isocyanates such as 2,4-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, and xylylene diisocyanate; isocyanate adducts such as trimethylolpropane / tolylene diisocyanate trimer adduct (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name "Coronate L"), trimethylolpropane / hexamethylene diisocyanate trimer adduct (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name "Coronate HL"), and isocyanurate derivative of hexamethylene diisocyanate (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name "Coronate HX"); and the like. Preferably, a crosslinking agent having three or more isocyanate groups is used.

[0057] Active energy ray curing adhesives may further contain any suitable additives as needed. Examples of additives include active energy ray polymerization accelerators, radical scavengers, tackifiers, plasticizers (e.g., trimellitic acid ester plasticizers, pyromellitic acid ester plasticizers, etc.), pigments, dyes, fillers, antioxidants, conductive materials, antistatic agents, UV absorbers, light stabilizers, release modifiers, softeners, surfactants, flame retardants, antioxidants, and the like.

[0058] • Pressure-sensitive adhesive: Examples of pressure-sensitive adhesives include acrylic adhesives, rubber adhesives, vinyl alkyl ether adhesives, silicone adhesives, polyester adhesives, polyamide adhesives, urethane adhesives, and styrene-diene block copolymer adhesives. Among these, acrylic adhesives or rubber adhesives are preferred, and acrylic adhesives are more preferred. These adhesives may be used individually or in combination of two or more types.

[0059] Examples of the above acrylic adhesives include acrylic adhesives that use an acrylic polymer (homopolymer or copolymer) as a base polymer, in which one or more alkyl (meth)acrylate esters are used as monomer components. Specific examples of alkyl (meth)acrylate esters include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, and (meth) Examples of C1-20 alkyl esters of (meth)acrylate include nonyl acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate, nonadecyl (meth)acrylate, and eicosyl (meth)acrylate. Among these, alkyl esters of (meth)acrylate having a linear or branched alkyl group with 4 to 18 carbon atoms are preferably used.

[0060] The above acrylic polymer may, if necessary, contain units corresponding to other monomer components copolymerizable with the above alkyl (meth)acrylate, for the purpose of modifying properties such as cohesiveness, heat resistance, and crosslinkability. Examples of such monomeric components include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; acid anhydride monomers such as maleic anhydride and eicotanoic anhydride; hydroxyl group-containing monomers such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, hydroxyhexyl (meth)acrylate, hydroxyoctyl (meth)acrylate, hydroxydecyl (meth)acrylate, hydroxylauryl (meth)acrylate, and (4-hydroxymethylcyclohexyl)methyl methacrylate; sulfonic acid group-containing monomers such as styrene sulfonic acid, allyl sulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, (meth)acrylamidepropanesulfonic acid, sulfopropyl (meth)acrylate, and (meth)acryloyloxynaphthalenesulfonic acid; (meth (N-substituted)amide monomers such as acrylamide, N,N-dimethyl(meth)acrylamide, N-butyl(meth)acrylamide, N-methylol(meth)acrylamide, N-methylolpropane(meth)acrylamide; (meth)acrylate aminoalkyl monomers such as aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, t-butylaminoethyl (meth)acrylate; (meth)acrylate alkoxyalkyl monomers such as methoxyethyl (meth)acrylate and ethoxyethyl (meth)acrylate; maleimide monomers such as N-cyclohexylmaleimide, N-isopropylmaleimide, N-laurylmaleimide, N-phenylmaleimide; itaconimide monomers such as N-methylitaconimide, N-ethylitaconimide, N-butylitaconimide, N-octylitaconimide, N-2-ethylhexylitaconimide, N-cyclohexylitaconimide, N-laurylitaconimide;Succinimide monomers such as N-(meth)acryloyloxymethylenesuccinimide, N-(meth)acryloyl-6-oxyhexamethylenesuccinimide, and N-(meth)acryloyl-8-oxyoctamethylenesuccinimide; vinyl monomers such as vinyl acetate, vinyl propionate, N-vinylpyrrolidone, methylvinylpyrrolidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazole, vinyloxazole, vinylmorpholine, N-vinyl carboxylic acid amides, styrene, α-methylstyrene, and N-vinylcaprolactam; cyanoacrylate monomers such as acrylonitrile and methacrylonitrile; epoxy group-containing acrylic monomers such as glycidyl (meth)acrylate; polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, methoxyethylene glycol (meth)acrylate, and (meth)acrylic acid Examples include glycol-based acrylic ester monomers such as methoxypolypropylene glycol phosphate; acrylic acid ester monomers having heterocyclic rings, halogen atoms, silicon atoms, etc., such as tetrahydrofurfuryl (meth)acrylate, fluorine (meth)acrylate, and silicone (meth)acrylate; polyfunctional monomers such as hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy acrylate, polyester acrylate, and urethane acrylate; olefin-based monomers such as isoprene, butadiene, and isobutylene; and vinyl ether-based monomers such as vinyl ether. These monomer components may be used individually or in combination of two or more.

[0061] Examples of the above-mentioned rubber-based adhesives include rubber-based adhesives that use natural rubber, polyisoprene rubber, styrene-butadiene (SB) rubber, styrene-isoprene (SI) rubber, styrene-isoprene-styrene block copolymer (SIS) rubber, styrene-butadiene-styrene block copolymer (SBS) rubber, styrene-ethylene-butylene-styrene block copolymer (SEBS) rubber, styrene-ethylene-propylene-styrene block copolymer (SEPS) rubber, styrene-ethylene-propylene block copolymer (SEP) rubber, recycled rubber, butyl rubber, polyisobutylene, and synthetic rubbers such as modified versions thereof as base polymers.

[0062] The above pressure-sensitive adhesive may contain any suitable additives as needed. Examples of such additives include crosslinking agents, tackifiers (e.g., rosin-based tackifiers, terpene-based tackifiers, hydrocarbon-based tackifiers, etc.), plasticizers (e.g., trimellitic acid ester plasticizers, pyromellitic acid ester plasticizers), pigments, dyes, antioxidants, conductive materials, antistatic agents, light stabilizers, release modifiers, softeners, surfactants, flame retardants, antioxidants, and the like.

[0063] B-3.Workpiece Any suitable workpiece can be used as the workpiece. In one embodiment, an electronic component is used as the workpiece.

[0064] In one embodiment, as shown in Figure 1, the workpiece 30 comprises another rigid substrate 31 and a member 32 disposed on at least one side of the other rigid substrate 31. The other rigid substrate may be the rigid substrate described in Section B-1. Alternatively, a rigid wiring circuit board or the like may be used as the other rigid substrate. Examples of the above-mentioned member include electronic components such as semiconductor elements and optoelectronic semiconductor elements. Specific examples of the workpiece include a rigid wiring circuit board on which multiple semiconductor elements for connection to the terminals are arranged in a row, and a glass carrier on which semiconductor elements are mounted with a double-sided adhesive sheet.

[0065] In another embodiment, a semiconductor wafer is used as the workpiece. The semiconductor wafer may be, for example, an optical semiconductor wafer such as an LED or a photodetector.

[0066] The above-mentioned workpieces may be arranged in multiple quantities or as a single unit.

[0067] When multiple workpieces are arranged, the spacing between them is, for example, 2 μm to 10 mm.

[0068] B-4. Base material As described above, in one embodiment, a base material 21 and an adhesive layer 22 may be further arranged between the ultraviolet absorbing layer 20 and the workpiece 30. In one embodiment, the laminate composed of the ultraviolet absorbing layer 20, the base material 21 and the adhesive layer 22 may be a double-sided adhesive sheet A. With this configuration, the double-sided adhesive sheet A can be peeled off in a subsequent process, and adhesive residue due to cohesive failure can be suppressed. Because adhesive residue can be significantly suppressed, the burden of the cleaning process to remove burnt residue, which is a problem in existing varnish methods, can be reduced. In addition, by providing a base material, the base material functions as a protective material and can prevent damage to the workpiece.

[0069] The above-mentioned substrate can be composed of any suitable resin. Examples of such resins include polyethylene resins, polypropylene resins, polybutene resins, polymethylpentene resins and other polyolefin resins, polyurethane resins, polyester resins, polyimide resins, polyetherketone resins, polystyrene resins, polyvinyl chloride resins, polyvinylidene chloride resins, fluorine resins, silicone resins, cellulose resins, ionomer resins, and the like. Among these, polyimide resins are particularly preferred. Using a substrate made of polyimide resin enhances the above-mentioned effects, efficiently prevents damage to the workpiece (device) by laser light incident from the glass substrate side, and allows selective peeling only from the glass substrate side.

[0070] The thickness of the above-mentioned substrate is preferably 1 μm to 300 μm, more preferably 1 μm to 100 μm, and even more preferably 1 μm to 50 μm.

[0071] The light transmittance of the substrate at a wavelength of 355 nm is preferably 90% or less, more preferably 85% or less, even more preferably 50% or less, and particularly preferably 15% or less. A lower light transmittance is preferable in that it can reduce damage to the substrate. The lower limit of the light transmittance of the substrate at a wavelength of 355 nm is, for example, 0%, and in one embodiment, it is 10%.

[0072] B-5.Adhesive layer The adhesive layer contains any suitable adhesive, for example, the pressure-sensitive adhesive described above.

[0073] In one embodiment, a heat-resistant adhesive is used as the adhesive contained in the adhesive layer. By providing an adhesive layer composed of a heat-resistant adhesive, scorching (adhesive residue) to the workpiece (device) when irradiated with laser light can be suppressed. In this specification, a heat-resistant adhesive means an adhesive that has a predetermined adhesive strength in an environment of 260°C. It is preferable that the heat-resistant adhesive can be used without leaving any adhesive residue in an environment of 260°C. Preferably, the heat-resistant adhesive contains an acrylic resin, a silicone resin, etc. as a base polymer.

[0074] C. Processing process In the processing step, the workpiece placed on the hard substrate as described above is processed. The processing in this step can be any appropriate process. Examples include a heating step, back grinding step, dicing step, mounting (reflow) step, and circuit formation (RDL) step. In Figure 1, a press machine equipped with an upper plate 100 and a lower plate 200 processes (heats) the laminate formed in the lamination step while pressing it (or after pressing).

[0075] In one embodiment, if the ultraviolet absorbing layer contains an active energy ray curing adhesive, the ultraviolet absorbing layer may be irradiated with active energy rays (e.g., ultraviolet light) before the above processing to increase its adhesive strength.

[0076] D. Peeling process In the peeling process, ultraviolet light is irradiated onto the ultraviolet absorption layer to peel the hard substrate from the workpiece.

[0077] In one embodiment, as shown in Figure 1, the hard substrate 10 is peeled off from the UV-absorbing layer 20, and then the UV-absorbing layer 20 is peeled off. If the double-sided adhesive sheet A is composed of the UV-absorbing layer 20, the substrate 21, and the adhesive layer 22, then after the UV-absorbing layer 20 is peeled off, the double-sided adhesive sheet A is peeled off.

[0078] In another embodiment, the hard substrate and the ultraviolet absorbing layer are peeled off together as a single unit.

[0079] The conditions for UV irradiation can be any appropriate conditions depending on the configuration of the UV absorption layer, as long as they can cause peelability in the UV absorption layer. In one embodiment, UV laser light (e.g., wavelength: 200 nm to 380 nm) is irradiated onto the UV absorption layer. By irradiating the UV absorption layer with UV laser light at any appropriate power (e.g., 0.01 W to 6 W, preferably 0.05 W to 5 W), deformation occurs in the UV absorption layer due to gases generated by the decomposition of the UV absorber and / or gases generated by the decomposition of the adhesive layer due to the heat generated by the UV absorber, resulting in peelability in the area irradiated with laser light. The wavelength of the UV laser light is preferably 360 nm or less. When a hard substrate is placed directly on one side of the UV absorption layer and the workpiece is placed directly on the other side of the UV absorption layer, peeling by UV laser irradiation is preferably performed.

[0080] If the ultraviolet absorption layer contains an active energy ray curing adhesive, the adhesive strength of the ultraviolet absorption layer may be reduced by irradiating the entire ultraviolet absorption layer with active energy rays. In one embodiment, the adhesive strength of the ultraviolet absorption layer may be reduced by irradiating the entire ultraviolet absorption layer with active energy rays after irradiation with UV laser light. Examples of active energy rays include gamma rays, ultraviolet rays, visible light, infrared rays (heat rays), radio waves, alpha rays, beta rays, electron beams, plasma streams, ionization rays, particle beams, etc. Ultraviolet rays are preferred. The wavelength of the ultraviolet rays is preferably 300 nm to 400 nm. The irradiation dose is, for example, an integrated light dose of 300 mJ / cm². 2 ~1500 mJ / cm 2 Thus, by irradiating with an active energy beam before laser light irradiation, re-adhesion can be prevented and the hard substrate can be peeled off.

[0081] As described above, the processing of the workpiece is completed. In this invention, the hard substrate can be peeled off by irradiating the ultraviolet absorption layer with ultraviolet light, and because the peeling force at that time is low, the load on the workpiece can be reduced, and as a result, damage to the workpiece can be prevented. [Examples]

[0082] (Lamination process) A workpiece 30 was prepared by placing a semiconductor element 32 (component 32) on terminals on a rigid wiring circuit board 31 (another rigid substrate 31). A glass substrate 10 (rigid substrate 10) was placed on top of a semiconductor element 32 and fixed using a double-sided adhesive sheet containing an ultraviolet absorbing layer 20. As a double-sided adhesive sheet, a PI base material 21 was used, with an ultraviolet absorption layer 20 containing an ultraviolet-curing adhesive formed on one side and an adhesive layer 22 formed on the other side. (Processing process) The laminate obtained in the above lamination process was pressed into a press machine to embed the semiconductor element 32 in the adhesive layer 22 and hold it in place. Remove the top plate of the press machine and expose the glass substrate 10 (hard substrate 10) to ultraviolet light (wavelength: 355nm~365nm, integrated light intensity: 1380mJ / cm²). 2 The ultraviolet absorption layer 20 was irradiated with a UV light to harden the UV absorption layer and reduce the adhesive strength of the UV absorption layer to the glass substrate 10 (hard substrate 10). The semiconductor element 32 (component 32) was heated while being pressed with a press machine to fix it to the terminals on the rigid wiring circuit board 31 (another rigid substrate 31). As a fixing method, metal bonding such as solder, ACF (anisotropic conductive film), ACP (anisotropic conductive paste), etc., can be used. (Peeling process) Remove the top plate of the press machine and expose the glass substrate 10 (hard substrate 10) to ultraviolet laser light (wavelength: 355nm; irradiation energy: 10J / cm²). 2 The glass substrate 10 (hard substrate 10) was peeled off by irradiating the ultraviolet absorption layer with ). Next, the double-sided adhesive sheet was peeled off. There was no damage to the semiconductor element 32 (component 32). Furthermore, the semiconductor element 32 (component 32) did not detach from the rigid wiring circuit board 31 (another rigid substrate 31). [Explanation of Symbols]

[0083] 10. Rigid substrate 20 UV-absorbing layer 30 Workpiece

Claims

1. A lamination process in which a hard substrate, an ultraviolet absorbing layer, and a workpiece are laminated in this order, and then, A processing step for processing the workpiece, and thereafter, A step of peeling the hard substrate from the workpiece, comprising a peeling step of irradiating the ultraviolet absorption layer with UV laser light and irradiating the entire ultraviolet absorption layer with active energy rays to reduce the adhesive strength of the ultraviolet absorption layer, The UV-absorbing layer contains a UV-absorbing agent, The UV absorber is a benzotriazole-based UV absorber, a benzophenone-based UV absorber, a triazine-based UV absorber, a salicylate-based UV absorber, or a cyanoacrylate-based UV absorber. The workpiece includes another hard substrate and a member disposed on at least one side of the other hard substrate, The component is an electronic component. Method for processing components.

2. The method for processing a component according to claim 1, wherein the hard substrate has light transmittance.

3. The method for processing a member according to claim 1 or 2, wherein the ultraviolet absorbing layer is adhesive.

4. The method for processing a component according to any one of claims 1 to 3, wherein the ultraviolet absorbing layer includes an active energy ray curing adhesive.

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