Method of processing a component

Abstract

A component processing method is provided that can prevent damage to the workpiece (component, etc.) even when a rigid substrate is peeled off from the workpiece. The component processing method of the present invention includes: a lamination step in which a rigid substrate, an ultraviolet absorbing layer, and a workpiece are sequentially laminated; a processing step in which the workpiece is processed; and a peeling step in which the ultraviolet absorbing layer is irradiated with ultraviolet light to peel the rigid substrate off from the workpiece.

Description

Technical Field

[0001] This invention relates to a method for processing components. Background Technology

[0002] In the processing of electronic components, considering the processability between steps, a set of substrates is sometimes used to clamp the component while processing it (e.g., Patent Document 1). For example, in the process of heat-pressing a component to a terminal on a wiring circuit board, while the component is temporarily placed on the terminal on the wiring circuit board, a steel plate is overlapped from above using a double-sided adhesive sheet, and the component is held under pressure while being heat-treated to fix the terminal. Then, after the heat treatment, the pressure is released, the steel plate is peeled off the component, and the component is fixed to the terminal on the wiring circuit board.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent No. 6691184 Summary of the Invention

[0006] The problem the invention aims to solve

[0007] In processes such as the heat-pressing process for bonding components on a wiring circuit board, where a component is held between a set of substrates (first substrate and second substrate) and then one substrate (second substrate) is peeled off from the component, if the second substrate being peeled off is rigid, it is difficult to bend, thus causing the second substrate (rigid substrate) to separate in the vertical direction. This results in problems such as the component being subjected to load, leading to component breakage, or the component unnecessarily detaching from the first substrate.

[0008] The present invention was made to solve the aforementioned prior art problems, and its object is to provide a component processing method that can prevent damage to the workpiece even when it includes peeling a rigid substrate from the workpiece (component, etc.).

[0009] Solution for solving the problem

[0010] The component processing method of the present invention includes: a stacking step, wherein a rigid substrate, an ultraviolet absorbing layer and a workpiece are stacked sequentially; thereafter, a processing step, wherein the workpiece is processed; and thereafter, a peeling step, wherein the ultraviolet absorbing layer is irradiated with ultraviolet light to peel the rigid substrate from the workpiece.

[0011] In one embodiment, the workpiece comprises: another rigid substrate and a member disposed on at least one side of the rigid substrate.

[0012] In one embodiment, the workpiece is a semiconductor wafer.

[0013] In one embodiment, the rigid substrate is light-transmitting.

[0014] In one embodiment, the ultraviolet absorbing layer has adhesive properties.

[0015] In one embodiment, the ultraviolet absorbing layer comprises an active energy ray curable adhesive.

[0016] In one embodiment, the ultraviolet absorbing layer comprises an ultraviolet absorber.

[0017] The effects of the invention

[0018] According to the present invention, a component processing method can be provided that can prevent damage to the workpiece even if it includes peeling a rigid substrate from the workpiece (component, etc.). Attached Figure Description

[0019] Figure 1 This is a schematic diagram illustrating a component processing method according to one embodiment of the present invention. Detailed Implementation

[0020] A. Overview of component processing methods

[0021] Figure 1 This is a schematic diagram illustrating a component processing method according to one embodiment of the present invention. The component processing method of the present invention includes: (i) a step of sequentially stacking a rigid substrate 10, an ultraviolet absorbing layer 20, and a workpiece 30 (hereinafter also referred to as a stacking step); (ii) a step of processing the workpiece 30 thereafter (processing step); and (iii) a step of irradiating the ultraviolet absorbing layer 20 with ultraviolet light to peel the rigid substrate 10 from the workpiece 30 (peeling step).

[0022] B. Lamination process

[0023] As described above, the lamination process involves sequentially stacking the rigid substrate 10, the ultraviolet absorbing layer 20, and the workpiece 30. In one embodiment, the ultraviolet absorbing layer has adhesive properties. The workpiece 30 in the example figure includes another rigid substrate 31 and a member 32 disposed on one side of the other rigid substrate 31.

[0024] In one embodiment, a substrate 21 and an adhesive layer 22 may be further disposed between the ultraviolet absorbing layer 20 and the workpiece 30. The ultraviolet absorbing layer 20, the substrate 21, and the adhesive layer 22 may be disposed sequentially. In one embodiment, the laminate composed of the ultraviolet absorbing layer 20, the substrate 21, and the adhesive layer 22 may be a double-sided adhesive sheet A.

[0025] In another embodiment, the rigid substrate and the workpiece may be disposed between them and the ultraviolet absorbing layer. More specifically, the rigid substrate is disposed directly on one side of the ultraviolet absorbing layer, and the workpiece is disposed directly on the other side of the ultraviolet absorbing layer.

[0026] B-1. Rigid substrate

[0027] The aforementioned rigid substrate refers to a plate-shaped molded body with a flexural modulus of elasticity of 1 GPa or higher. The flexural modulus of elasticity can be determined by a four-point bending test according to JIS K7171 or JIS R1602, depending on the material constituting the rigid substrate.

[0028] Any suitable material can be used as the material constituting the rigid substrate. Examples of rigid substrates include glass substrates, metal substrates, silicon substrates, sapphire substrates, and plastic substrates.

[0029] Preferably, the rigid substrate described above is light-transmitting. The ultraviolet (wavelength 360nm) transmittance of the rigid substrate is preferably 70% or more, more preferably 80% to 99.9%. If the rigid substrate is light-transmitting, peeling in the peeling process can preferably occur.

[0030] B-2. Ultraviolet Absorption Layer

[0031] The ultraviolet absorbing layer can be a layer that is initially adhesive (i.e., before ultraviolet irradiation) but exhibits peelability due to decreased adhesiveness after ultraviolet irradiation. In one embodiment, the ultraviolet absorbing layer can be a layer whose adhesiveness is locally reduced by localized ultraviolet irradiation (e.g., UV laser irradiation).

[0032] In one embodiment, the ultraviolet absorbing layer comprises an ultraviolet absorber. Preferably, the ultraviolet absorbing layer also comprises an adhesive. Examples of adhesives include pressure-sensitive adhesives and active energy radiation-cured adhesives.

[0033] By including a UV absorber in the UV-absorbing layer, the adhesion of the substrate can be peeled off by UV laser irradiation. More specifically, the UV absorber is irradiated with a UV laser, causing the UV absorber to decompose and generate gas, and / or the UV absorber heats up, causing the UV absorber layer to decompose and generate gas. The UV absorber layer deforms due to the aforementioned gas, resulting in the irradiated portion exhibiting peelability.

[0034] Furthermore, if the ultraviolet absorbing layer contains an active energy ray-curable adhesive, the overall adhesive strength of the ultraviolet absorbing layer can be reduced by irradiating it with active energy rays. In one embodiment, after the adhesive strength of the entire ultraviolet absorbing layer is reduced by irradiating it with active energy rays, a laser is irradiated as described above. This significantly prevents the re-adhesion of residual adhesive after peeling onto the rigid substrate, which is advantageous from the viewpoint of preventing contamination compared to conventional methods using varnishes. Examples of active energy rays include gamma rays, ultraviolet rays, visible light, infrared rays (thermal rays), radio waves, alpha rays, beta rays, electron beams, plasma streams, ionizing radiation, and particle beams. Ultraviolet rays are preferred.

[0035] The transmittance of the ultraviolet absorption layer at a wavelength of 360 nm is preferably 50% or less. By reducing this transmittance, the laser output during stripping can be reduced. The transmittance of the ultraviolet absorption layer at a wavelength of 355 nm is preferably 30% or less. The aforementioned effect becomes more significant when it is in this range. Furthermore, the transmittance of the ultraviolet absorption layer at a wavelength of 380 nm is preferably 30% or more, more preferably 50% or more.

[0036] The initial adhesion strength at 23°C when the ultraviolet absorbing layer is bonded to a stainless steel plate is preferably 0.1 N / 20 mm to 20 N / 20 mm, more preferably 0.5 N / 20 mm to 15 N / 20 mm. Within this range, an ultraviolet absorbing layer that can well retain the workpiece can be formed. The adhesion strength is measured according to JIS Z0237:2000. Specifically, the ultraviolet absorbing layer is bonded to a stainless steel plate (arithmetic mean surface roughness Ra: 50 ± 25 nm) by passing a 2 kg roller back and forth once. After being placed at 23°C for 30 minutes, the ultraviolet absorbing layer is peeled off at a peel angle of 180° and a peel speed (tension speed) of 300 mm / min, and the adhesion strength is measured. The adhesion strength of the ultraviolet absorbing layer changes under irradiation with active energy rays and laser irradiation. In this specification, "initial adhesion strength" refers to the adhesion strength before irradiation with active energy rays and laser.

[0037] In one embodiment, the ultraviolet absorbing layer is attached to a stainless steel plate and irradiated with 460 mJ / cm². 2 The adhesion strength at 23°C after UV irradiation is preferably 0.01 N / 20 mm to 2 N / 20 mm, more preferably 0.02 N / 20 mm to 1 N / 20 mm. Within this range, a UV-absorbing layer with minimal adhesive residue can be formed. The aforementioned UV irradiation is, for example, performed using a UV irradiation device (manufactured by Nitto Seiki Co., Ltd., trade name "UM-810") to irradiate the UV-absorbing layer with ultraviolet light from a high-pressure mercury lamp (characteristic wavelength: 365 nm, cumulative light intensity: 460 mJ / cm²). 2 Irradiation energy: 70W / cm 2Irradiation time: 6.6 seconds.

[0038] The thickness of the ultraviolet absorbing layer is preferably 50 μm or less. Within this range, laser output during stripping can be further reduced. More preferably, the thickness of the ultraviolet absorbing layer is 40 μm or less, even more preferably 30 μm or less, and even more preferably 1 μm to 30 μm. Within this range, the aforementioned effects become significant.

[0039] • Ultraviolet absorber:

[0040] As a UV absorber, any suitable UV absorber can be used 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 or benzotriazole-based UV absorbers are preferred, and triazine-based UV absorbers are particularly preferred. Especially when using an acrylic adhesive as adhesive A, triazine-based UV absorbers are preferred from the perspective of 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 preferred to be UV absorbers composed of hydroxyphenyltriazine compounds (hydroxyphenyltriazine-based UV absorbers).

[0041] As a hydroxyphenyl triazine-based ultraviolet absorber, for example, the reaction product of 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hydroxyphenyl with [(C10-C16 (mainly C12-C13)alkyloxy)methyl]ethylene oxide (trade name "TINUVIN") can be cited. 400” (manufactured by BASF), 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl]-5-[3-(dodecyloxy)-2-hydroxypropoxy]phenol), the reaction product of 2-(2,4-dihydroxyphenyl)-4,6-bis-(2,4-dimethylphenyl)-1,3,5-triazine with (2-ethylhexyl)-glycidyl ester (trade name "TINUVIN 405", manufactured by BASF), 2,4-bis(2-hydroxy-4-butoxyphenyl)-6-(2,4-dibutoxyphenyl)-1,3,5-triazine (trade name "TINUVIN 460", manufactured by BASF), 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]-phenol (trade name "TINUVIN"). 1577 (manufactured by BASF), 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[2-(2-ethylhexanoyloxy)ethoxy]-phenol (trade name "ADK STAB LA-46", manufactured by ADEKA Corporation), 2-(2-hydroxy-4-[1-octyloxycarbonylethoxy]phenyl)-4,6-bis(4-phenylphenyl)-1,3,5-triazine (trade name "TINUVIN 479", manufactured by BASF), BASF's trade name "TINUVIN 477", etc.

[0042] Examples of benzotriazole-based ultraviolet absorbers (benzotriazole compounds) include, for example, 2-(2-hydroxy-5-tert-butylphenyl)-2H-benzotriazole (trade name "TINUVIN PS", manufactured by BASF), phenylpropionic acid and esters of 3-(2H-benzotriazole-2-yl)-5-(1,1-dimethylethyl)-4-hydroxy (C7-9 side chain and straight-chain alkyl) (trade name "TINUVIN 384-2", manufactured by BASF), and a mixture of octyl 3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazole-2-yl)phenyl]propionate and 2-ethylhexyl-3-[3-tert-butyl-4-hydroxy-5-(5-chloro-2H-benzotriazole-2-yl)phenyl]propionate (trade name "TINUVIN"). 109” (manufactured by BASF), 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol (trade name "TINUVIN 900", manufactured by BASF), 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol (trade name "TINUVIN 928", manufactured by BASF), methyl 3-(3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl)propionate / polyethylene glycol 300 reaction product (trade name "TINUVIN 1130", manufactured by BASF), 2-(2H-benzotriazol-2-yl)-p-cresol (trade 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[3-Tetramethylbutyl)phenol] (trade name "TINUVIN 360", manufactured by BASF), methyl 3-(3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl)propionate reacting with 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-tetrahydrophthalimide-methyl)-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 (trade name "SEESORB 703", manufactured by SHIPRO) (Manufactured by SHIPRO KASEI), 2-(2H-benzotriazol-2-yl)-4-methyl-6-(3,4,5,6-tetrahydrophthalimidemethyl)phenol (trade name "SEESORB706", manufactured by SHIPRO KASEI), 2-(4-benzoyloxy-2-hydroxyphenyl)-5-chloro-2H-benzotriazole (manufactured by SHIPRO KASEI, trade name "SEESORB7012BA"), 2-tert-butyl-6-(5-chloro-2H-benzotriazol-2-yl)-4-methylphenol (trade name "KEMISORB 73", manufactured by Chemipro Kasei), 2,2'-methylenebis[6-(2H-benzotriazol-2-yl)-4-tert-octylphenol] (trade name "ADK STAB") Products include: LA-31 (manufactured by ADEKA Corporation), 2-(2H-benzotriazol-2-yl)-p-cellulose (trade name "ADKSTAB LA-32", manufactured by ADEKA Corporation), and 2-(5-chloro-2H-benzotriazol-2-yl)-6-tert-butyl-4-methylphenol (trade name "ADK STAB LA-36", manufactured by ADEKA Corporation), etc.

[0043] The aforementioned ultraviolet absorbers can be dyes or pigments. Examples of pigments include azo, phthalocyanine, anthraquinone, lake, perylene, perinone, quinacridone, indigo, dioxazine, isoindolone, and quinophthalone pigments. Examples of dyes include azo, phthalocyanine, anthraquinone, carbonyl, indigo, quinone imine, methylene, quinoline, and nitro dyes.

[0044] 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. When it is in such a range, it is possible to form an ultraviolet absorbing layer that can form a better deformable portion through laser irradiation.

[0045] The maximum absorption wavelength of the aforementioned 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 aforementioned photopolymerization initiator is preferably 10 nm or more, more preferably 25 nm or more.

[0046] The 5% weight loss temperature of the aforementioned ultraviolet absorber is preferably 350°C or lower, more preferably 330°C or lower. The lower limit of the 5% weight loss temperature of the ultraviolet absorber is, for example, 100°C. Within this range, an ultraviolet absorbing layer can be formed that allows for better deformation through laser irradiation. The 5% weight loss temperature of the ultraviolet absorber refers to the temperature at which the weight of the ultraviolet absorber decreases by 5% by weight relative to its weight before heating. The 5% weight loss temperature is measured using a differential thermal analysis apparatus under the following conditions: heating temperature 10°C / min, air atmosphere, and flow rate 25 ml / min.

[0047] The proportion of the aforementioned ultraviolet absorber relative to 100 parts by weight of the base polymer in the ultraviolet absorbing layer is preferably 1 to 50 parts by weight, more preferably 5 to 20 parts by weight. Within this range, an ultraviolet absorbing layer can be formed that effectively reduces the overall adhesiveness of the ultraviolet absorbing layer when irradiated by active energy rays, and exhibits good peelability when irradiated by laser.

[0048] • Active energy radiation-cured adhesives:

[0049] In one embodiment, an active energy radiation-curable adhesive (A1) is used as an active energy radiation-curable adhesive, comprising a base polymer as a masterbatch and an active energy radiation-reactive compound (monomer or oligomer) capable of bonding with the base polymer. In another embodiment, an active energy radiation-curable adhesive (A2) is used, comprising an active energy radiation-reactive polymer as a base polymer. Preferably, the base polymer has a functional group capable of reacting with a photopolymerization initiator. Examples of such functional groups include hydroxyl and carboxyl groups.

[0050] Examples of base polymers used in the aforementioned adhesive (A1) include, for instance, natural rubber, polyisobutylene rubber, styrene-butadiene rubber, styrene-isoprene-styrene block copolymer rubber, reclaimed rubber, butyl rubber, polyisobutylene rubber, nitrile rubber (NBR), and other rubber-based polymers; silicone-based polymers; and acrylic polymers. These polymers can be used alone or in combination of two or more. Acrylic polymers are preferred.

[0051] Examples of acrylic polymers include homopolymers or copolymers of hydrocarbon-containing (meth)acrylates such as alkyl (meth)acrylates, cycloalkyl (meth)acrylates, and aryl (meth)acrylates; and copolymers of these hydrocarbon-containing (meth)acrylates with other comonomers. Examples of alkyl (meth)acrylates include, for example, methyl esters, ethyl esters, propyl esters, isopropyl esters, butyl esters, isobutyl esters, sec-butyl esters, tert-butyl esters, pentyl esters, isopentyl esters, hexyl esters, heptyl esters, octyl esters, 2-ethylhexyl esters, isooctyl esters, nonyl esters, decyl esters, isodecanyl 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, for example, cyclopentyl esters and cyclohexyl esters of (meth)acrylate. Examples of aryl (meth)acrylates include phenyl (meth)acrylate and benzyl (meth)acrylate. The proportion of the structural units derived from the above-mentioned hydrocarbon-containing (meth)acrylates is preferably 40 parts by weight or more, more preferably 60 parts by weight or more, relative to 100 parts by weight of the base polymer.

[0052] Examples of other copolymerizable monomers mentioned above include, for example, carboxyl-containing monomers, acid anhydride monomers, hydroxyl-containing monomers, glycidyl-containing monomers, sulfonic acid monomers, phosphate-containing monomers, acrylamide, and acrylonitrile, etc. Examples of carboxyl-containing monomers include, for example, acrylic acid, methacrylic acid, carboxyethyl methacrylate, carboxypentyl methacrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. Examples of acid anhydride monomers include, for example, maleic anhydride and itaconic anhydride. Examples of hydroxyl-containing monomers include, for example, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 6-hydroxyhexyl methacrylate, 8-hydroxyoctyl methacrylate, 10-hydroxydecyl methacrylate, 12-hydroxylauryl methacrylate, and methyl methacrylate (4-hydroxymethylcyclohexyl) Examples of monomers containing glycidyl groups include glycidyl (meth)acrylate and methyl glycidyl (meth)acrylate. Examples of monomers containing sulfonic acid groups include styrene sulfonic acid, allyl sulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, (meth)acrylamide propanesulfonic acid, (meth)acrylate sulfonylpropyl ester, and (meth)acryloyloxynaphthalene sulfonic acid. Examples of monomers containing phosphoric acid include 2-hydroxyethylacryloyl phosphate. Examples of acrylamides include N-acryloylmorpholine. These can be used alone or in combination of two or more. The proportion of structural units derived from the above-mentioned copolymeric monomers relative to 100 parts by weight of the base polymer is preferably 60 parts by weight or less, more preferably 40 parts by weight or less.

[0053] Acrylic polymers contain structural units derived from multifunctional monomers to form a crosslinked structure within their polymer backbone. Examples of multifunctional monomers include, for instance, hexanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene 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., poly(meth)acrylate glycidyl acrylate), polyester (meth)acrylate, and urethane (meth)acrylate. These can be used individually or in combination of two or more. The proportion of structural units derived from the above-mentioned multifunctional monomers relative to 100 parts by weight of the base polymer is preferably 40 parts by weight or less, more preferably 30 parts by weight or less.

[0054] The weight-average molecular weight of the above-mentioned acrylic polymers is preferably 100,000 to 3,000,000, more preferably 200,000 to 2,000,000. The weight-average molecular weight can be determined by GPC (solvent: THF).

[0055] Examples of photoreactive compounds that can be used in the aforementioned adhesive (A1) include, for instance, photoreactive monomers or oligomers having functional groups such as acryloyl, methacryl, vinyl, allyl, and ethynyl groups that possess polymerizable carbon-carbon multi-bonds. Specific examples of such photoreactive monomers include esters of (meth)acrylic acid and polyols 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, and polyethylene glycol di(meth)acrylate; polyfunctional urethane (meth)acrylates; epoxy (meth)acrylates; and low-polyester (meth)acrylates. Alternatively, monomers such as methacryloyl isocyanate, 2-methacryloyloxyethyl isocyanate (ethyl 2-isocyanate methacrylate), and m-isopropenyl-α,α-dimethylbenzyl isocyanate can also be used. Specific examples of photoreactive oligomers include 2- to 5-polymers of the above monomers. The molecular weight of the photoreactive oligomer is preferably between 100 and 3000.

[0056] In addition, monomers such as epoxide butadiene, glycidyl methacrylate, acrylamide, and vinylsiloxane, or oligomers composed of such monomers, can be used as the above-mentioned reactive energy radiation compounds.

[0057] Furthermore, as the aforementioned reactive compounds for active energy rays, a mixture of organic salts such as onium salts and compounds having multiple heterocycles within the molecule can be used. When this mixture is irradiated with active energy rays (e.g., ultraviolet light, electron beams), the organic salts are broken down to generate ions, which become the starting species, inducing a ring-opening reaction of the heterocycles, thereby forming a three-dimensional network structure. Examples of the aforementioned organic salts include, for example, iodonium salts, phosphonium salts, antimony salts, sulfonium salts, and borates. Examples of heterocycles in the aforementioned compounds having multiple heterocycles within the molecule include ethylene oxide, oxetane, oxepane, thiohexacyclopropane, and aziridine.

[0058] In the above-mentioned adhesive (A1), the proportion of the active energy ray reactive compound relative to 100 parts by weight of the base polymer is preferably 0.1 parts by weight to 500 parts by weight, more preferably 5 parts by weight to 300 parts by weight, and even more preferably 40 parts by weight to 150 parts by weight.

[0059] Examples of active energy ray-reactive polymers (basic polymers) included in the aforementioned adhesive (A2) include polymers having functional groups with carbon-carbon multiple bonds, such as acryloyl, methacryloyl, vinyl, allyl, and ethynyl groups. Specific examples of active energy ray-reactive polymers include polymers composed of polyfunctional (meth)acrylates; photocationic polymers; cinnamoyl-containing polymers such as polyvinyl cinnamate; diazotized aminophenolic varnish resins; polyacrylamide; and so on.

[0060] In one embodiment, an active energy-ray reactive polymer is used, which is formed by introducing active energy-ray polymerizable carbon-carbon double bonds into the side chains, main chains, and / or main chain ends of the aforementioned acrylic polymer. As a method for introducing radiation-polymerizable carbon-carbon double bonds into the acrylic polymer, for example, the following method can be used: after copolymerizing a raw material monomer containing a monomer having a predetermined functional group (first functional group) to obtain an acrylic polymer, a compound having a predetermined functional group (second functional group) capable of reacting and bonding with the first functional group and radiation-polymerizable carbon-carbon double bonds is subjected to a condensation reaction or addition reaction with the acrylic polymer while maintaining the radiation-polymerizable nature of the carbon-carbon double bonds.

[0061] Examples of combinations of the first and second functional groups include carboxyl and epoxy groups, epoxy and carboxyl groups, carboxyl and aziridinyl groups, aziridinyl and carboxyl groups, hydroxyl and isocyanate groups, and isocyanate and hydroxyl groups. Among these combinations, from the viewpoint of ease of reaction tracking, combinations of hydroxyl and isocyanate groups and combinations of isocyanate and hydroxyl groups are preferred. Furthermore, producing polymers with highly reactive isocyanate groups is technically difficult; therefore, from the viewpoint of ease of production or acquisition of acrylic polymers, the case where the first functional group on the acrylic polymer side is a hydroxyl group and the second functional group is an isocyanate group is more preferred. In this case, examples of isocyanate compounds possessing both a radially 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 an acrylic polymer having a first functional group, it is preferable to include structural units derived from the hydroxyl-containing monomers mentioned above, and it is also preferable to include structural units derived from ether compounds such as 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, and diethylene glycol monovinyl ether.

[0062] The adhesive (A2) may also contain the above-mentioned reactive energy ray compound (monomer or oligomer).

[0063] The aforementioned active energy ray-cured adhesives may contain photopolymerization initiators.

[0064] Any suitable initiator can be used as a photopolymerization initiator. Examples of photopolymerization initiators include α-keto alcohol compounds such as 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)one, α-hydroxy-α,α'-dimethylacetophenone, 2-methyl-2-hydroxyphenylacetone, 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-morpholinylpropane-1; benzoin ether compounds such as benzoin ethyl ether, benzoin isopropyl ether, and anisolein methyl ether; and benzoin dimethyl ether. Ketal compounds such as ketals; aromatic sulfonyl chloride compounds such as 2-naphthalenesulfonyl chloride; photoactive oxime compounds such as 1-benzophenone-1,1-propanedione-2-(o-ethoxycarbonyl)oxime; benzophenone compounds such as benzoylbenzoic acid and 3,3'-dimethyl-4-methoxybenzophenone; thioxanthone compounds such as 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, and 2,4-diisopropylthioxanthone; camphorquinone; haloketones; acylphosphine oxides; acylphosphonates, etc. The amount of photopolymerization initiator used can be set to any appropriate amount.

[0065] 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. If such a photopolymerization initiator is used, the curing reaction of the adhesive preferably occurs when the overall adhesion of the ultraviolet absorbing layer is reduced by irradiation with active energy rays, and an ultraviolet absorbing layer with particularly little adhesive residue can be formed.

[0066] Commercially available products can be used as the aforementioned photopolymerization initiators. For example, examples of photopolymerization initiators with the maximum absorption wavelength below 400 nm include those manufactured by BASF under the trade names "Irgacure 127", "Irgacure 369", "Irgacure 369E", "Irgacure 379", "Irgacure 379EG", "Irgacure 819", "IrgacureTOP", "Irgacure 784", and "Irgacure OXE01".

[0067] In one embodiment, the above-mentioned active energy ray curable adhesive may contain a photosensitizer.

[0068] In one embodiment, the photosensitizer can be used in combination with the photopolymerization initiator. The photosensitizer transfers the energy gained from absorbing light to the photopolymerization initiator, thereby enabling the initiator to generate free radicals. Therefore, polymerization can be performed using light from the longer wavelength side where the photopolymerization initiator itself does not have an absorption peak. Thus, by including the photosensitizer, the difference between the absorption wavelength of the ultraviolet absorber and the wavelength at which free radicals can be generated by the photopolymerization initiator can be increased. As a result, photopolymerization of the ultraviolet-absorbing layer and stripping based on the ultraviolet absorber can proceed without affecting each other. In one embodiment, 2,2-dimethoxy-1,2-diphenylethane-1-one (e.g., manufactured by BASF, trade name "Irgacure 651"), used as the 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 (e.g., "UVS1101" manufactured by Kawasaki Chemical Industries, Ltd.).

[0069] Other examples of the aforementioned photosensitizers include 9,10-dibutoxyanthracene (e.g., manufactured by Kawasaki Chemical Industry Co., Ltd., trade name "UVS-1331"), 2-isopropylthioxanthone, benzophenone, thioxanthone derivatives, and 4,4'-bis(dimethylamino)benzophenone. Examples of thioxanthone derivatives include ethoxycarbonylthioxanthone and isopropylthioxanthone.

[0070] The proportion of the photosensitizer relative to 100 parts by weight of the base polymer is preferably 0.01 to 2 parts by weight, more preferably 0.5 to 2 parts by weight.

[0071] Preferably, the above-mentioned active energy radiation-curable adhesive includes 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, and amine-based crosslinking agents.

[0072] The crosslinking agent is preferably 0.5 to 10 parts by weight, more preferably 1 to 8 parts by weight, relative to 100 parts by weight of the base polymer of the adhesive.

[0073] 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 aforementioned 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-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, and phenyl dimethyl diisocyanate; trimethylolpropane / toluene 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 esters of hexamethylene diisocyanate (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name "CORONATE"). Isocyanate adducts such as HX”; etc. Crosslinking agents having three or more isocyanate groups are preferred.

[0074] Active energy radiation-cured adhesives may also contain any suitable additives as needed. Examples of additives include, for instance, active energy radiation polymerization accelerators, free radical scavengers, tackifiers, plasticizers (e.g., trimellitate plasticizers, pyromellitic ester plasticizers, etc.), pigments, dyes, fillers, antioxidants, conductive materials, antistatic agents, UV absorbers, light stabilizers, peel modifiers, softeners, surfactants, flame retardants, antioxidants, etc.

[0075] Pressure-sensitive adhesives:

[0076] 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. Acrylic adhesives or rubber adhesives are preferred, and acrylic adhesives are more preferably used. It should be noted that the above adhesives can be used alone or in combination of two or more.

[0077] Examples of acrylic adhesives include acrylic adhesives that use acrylic polymers (homopolymers or copolymers) with one or more (meth)acrylate alkyl esters as monomer components as base polymers. Specific examples of alkyl methacrylates include methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, tert-butyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate, isooctyl methacrylate, nonyl methacrylate, isononyl methacrylate, decyl methacrylate, isodecanyl methacrylate, undecyl methacrylate, dodecyl methacrylate, tridecyl methacrylate, tetradecyl methacrylate, pentadecyl methacrylate, hexadecyl methacrylate, heptadecanyl methacrylate, octadecyl methacrylate, nonadecanyl methacrylate, eicosyl methacrylate, and other C1-20 alkyl methacrylates. Preferably, alkyl (meth)acrylates having straight-chain or branched alkyl groups having 4 to 18 carbon atoms can be used.

[0078] For the purpose of improving cohesion, heat resistance, crosslinking properties, etc., the above-mentioned acrylic polymers may, as needed, contain units corresponding to other monomer components that can copolymerize with the above-mentioned alkyl methacrylates. Examples of such monomer components include, for example, carboxyl-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; anhydride monomers such as maleic anhydride and itaconic anhydride; hydroxyl-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 methyl methacrylate (4-hydroxymethylcyclohexyl)methacrylate; and styrene sulfonic acid, allyl sulfonic acid, 2-(meth)acrylamide-2-methylpropanesulfonic acid, and (meth)acrylic acid. Monomers containing sulfonic acid groups, such as methacrylamide propanesulfonic acid, sulfonyl propionate (meth)acrylate, and methacryloyloxynaphthalenesulfonic acid; (N-substituted) amide monomers, such as (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-butyl(meth)acrylamide, N-hydroxymethyl(meth)acrylamide, and N-hydroxymethylpropane(meth)acrylamide; (meth)acrylate aminoethyl ester monomers, such as N,N-dimethylaminoethyl ester (meth)acrylate and tert-butylaminoethyl ester (meth)acrylate; (meth)acrylate alkoxyalkyl ester monomers, such as methoxyethyl ester (meth)acrylate and ethoxyethyl ester (meth)acrylate; N- Cyclohexylmaleimide, N-isopropylmaleimide, N-laurylmaleimide, N-phenylmaleimide and other maleimide monomers; N-methylitaconimide, N-ethylitaconimide, N-butylitaconimide, N-octylitaconimide, N-2-ethylhexylitaconimide, N-cyclohexylitaconimide, N-laurylitaconimide and other itconimide monomers; N-(meth)acryloyloxymethylenesuccinimide, N-(meth)acryloyl-6-oxyhexamethylenesuccinimide, N-(meth)acryloyl-8-oxyoctamethylenesuccinimide and other succinimide monomers; vinyl acetate, vinyl propionate Vinyl monomers such as N-vinylpyrrolidone, methylvinylpyrrolidone, vinylpyridine, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazolium, vinyloxazole, vinylmorpholine, N-vinylcarboxylic amides, styrene, α-methylstyrene, and N-vinylcaprolactam; cyanoacrylate monomers such as acrylonitrile and methacrylonitrile; epoxy-containing acrylic monomers such as glycidyl acrylate; diol-based acrylate monomers such as polyethylene glycol acrylate, polypropylene glycol acrylate, methoxyethylene glycol acrylate, and methoxypolypropylene glycol acrylate.Acrylate monomers containing heterocyclic rings, halogen atoms, or silicon atoms, such as tetrahydrofurfuryl methacrylate, fluoromethacrylate, and organosilicon methacrylate; multifunctional monomers such as hexanediol dimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, neopentyl glycol dimethacrylate, pentaerythritol dimethacrylate, trimethylolpropane trimethacrylate, pentaerythritol trimethacrylate, dipentaerythritol hexamethacrylate, epoxy acrylate, polyester acrylate, and urethane acrylate; olefin monomers such as isoprene, butadiene, and isobutylene; and vinyl ether monomers such as vinyl ethers. These monomer components can be used alone or in combination of two or more.

[0079] Examples of rubber-based adhesives include those using 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-butene-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 their modified forms as the base polymer.

[0080] The pressure-sensitive adhesive described above 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., trimellitate-based plasticizers, pyromellitic ester-based plasticizers), pigments, dyes, antioxidants, conductive materials, antistatic agents, light stabilizers, peel modifiers, softeners, surfactants, flame retardants, antioxidants, etc.

[0081] B-3. ​​Workpiece

[0082] Any suitable workpiece can be used as the workpiece. In one embodiment, an electronic component is used as the workpiece.

[0083] In one implementation, such as Figure 1As shown, the workpiece 30 includes: another rigid substrate 31, and a member 32 disposed on at least one side of the other rigid substrate 31. The rigid substrate described in section B-1 can be used as the other rigid substrate. Alternatively, a rigid wiring circuit board or the like can also be used as the other rigid substrate. Examples of the aforementioned member include, for example, electronic components such as semiconductor elements and opto-semiconductor elements. Specific examples of the workpiece include: a plurality of semiconductor elements for connection to terminals mounted side-by-side on terminals of a rigid wiring circuit board, or semiconductor elements mounted on a glass substrate using double-sided adhesive sheets.

[0084] In another embodiment, a semiconductor wafer is used as the workpiece described above. The semiconductor wafer may be, for example, a light semiconductor wafer such as an LED or a light-receiving element.

[0085] The aforementioned workpieces can be configured in multiple ways or in a single way.

[0086] When multiple workpieces are configured, the spacing between them is, for example, 2μm to 10mm.

[0087] B-4. Substrate

[0088] As described above, in one embodiment, a substrate 21 and an adhesive layer 22 may be further disposed between the ultraviolet absorbing layer 20 and the workpiece 30. In one embodiment, the laminate composed of the ultraviolet absorbing layer 20, the substrate 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, suppressing residual adhesive caused by cohesive failure. Since residual adhesive can be significantly suppressed, the cleaning process for removing problematic burnt residue in conventional varnishing processes can be reduced. In addition, by including the substrate, which functions as a protective material, damage to the workpiece can be prevented.

[0089] The aforementioned substrate can be made of any suitable resin. Examples of such resins include, for instance, polyethylene-based resins, polypropylene-based resins, polybutene-based resins, polymethylpentene-based resins, polyolefin-based resins, polyurethane-based resins, polyester-based resins, polyimide-based resins, polyetherketone-based resins, polystyrene-based resins, polyvinyl chloride-based resins, polyvinylidene chloride-based resins, fluorine-based resins, silicone-based resins, cellulose-based resins, and ionomer resins. Polyimide-based resins are preferred. When a substrate made of a polyimide-based resin is used, the aforementioned effects become significant, and damage to the workpiece (device) caused by laser light incident from the glass substrate side can be effectively prevented, allowing for selective peeling only from the glass substrate side.

[0090] The thickness of the above-mentioned substrate is preferably 1μm to 300μm, more preferably 1μm to 100μm, and even more preferably 1μm to 50μm.

[0091] The transmittance of the substrate at a wavelength of 355 nm is preferably 90% or less, more preferably 85% or less, further preferably 50% or less, and particularly preferably 15% or less. The lower the transmittance, the better in reducing the loss of the adhered material. The lower limit of the transmittance of the substrate at a wavelength of 355 nm is, for example, 0%, and in one embodiment, 10%.

[0092] B-5. Adhesive layer

[0093] The adhesive layer contains any suitable adhesive. For example, it may contain the pressure-sensitive adhesive described above.

[0094] In one embodiment, a heat-resistant adhesive is used as the adhesive included in the adhesive layer. By having an adhesive layer composed of a heat-resistant adhesive, scorching (residue) on the workpiece (device) during laser irradiation can be suppressed. In this specification, a heat-resistant adhesive refers to an adhesive that has a specified adhesive strength at an environment of 260°C. Preferably, the heat-resistant adhesive can be used without residue at an environment of 260°C. Preferably, the heat-resistant adhesive contains an acrylic resin, a silicone resin, or the like as a base polymer.

[0095] C. Processing steps

[0096] In the processing steps, the workpiece disposed on the rigid substrate as described above is processed. This processing step can be any suitable processing step. For example, heating steps, back-side grinding steps, cutting steps, mounting (reflow soldering) steps, circuit forming (RDL) steps, etc. Figure 1 In the process, a press equipped with an upper plate 100 and a lower plate 200 is used to press the laminate formed in the lamination process, and at the same time (or after pressing), the laminate is processed (heated).

[0097] In one embodiment, if the ultraviolet absorbing layer contains an active energy ray curable adhesive, the adhesive strength of the ultraviolet absorbing layer can be improved by irradiating the ultraviolet absorbing layer with active energy rays (e.g., ultraviolet rays) before the above processing.

[0098] D. Stripping process

[0099] In the peeling process, ultraviolet light is irradiated onto the ultraviolet-absorbing layer to peel the rigid substrate from the workpiece.

[0100] In one implementation, such as Figure 1As shown, after the rigid substrate 10 is peeled off from the ultraviolet absorbing layer 20, the ultraviolet absorbing layer 20 is also peeled off. In the case where the double-sided adhesive sheet A is composed of the ultraviolet absorbing layer 20, the substrate 21, and the adhesive layer 22, the double-sided adhesive sheet A is peeled off after the ultraviolet absorbing layer 20 is peeled off.

[0101] In another embodiment, the rigid substrate and the ultraviolet absorbing layer are peeled off as a single unit.

[0102] For each condition of ultraviolet irradiation, as long as it enables the ultraviolet absorbing layer to peel off, any suitable condition can be set according to the composition of the ultraviolet absorbing layer. In one embodiment, the ultraviolet absorbing layer is irradiated with a UV laser (e.g., wavelength: 200nm to 380nm). By irradiating the ultraviolet absorbing layer with a UV laser at any suitable output (e.g., 0.01W to 6W, preferably 0.05W to 5W), the ultraviolet absorber decomposes to generate gas, and / or the ultraviolet absorber heats up, causing the adhesive layer to decompose and generate gas. The gas causes deformation of the ultraviolet absorbing layer, resulting in the irradiated portion exhibiting peelability. The wavelength of the UV laser is preferably 360nm or less. When a rigid substrate is directly disposed on one side of the ultraviolet absorbing layer and the workpiece is directly disposed on the other side of the ultraviolet absorbing layer, peeling based on UV laser irradiation is preferred.

[0103] When the ultraviolet-absorbing layer contains an active energy ray-curable adhesive, the entire ultraviolet-absorbing layer can be irradiated with active energy rays to reduce its adhesive strength. In one embodiment, the adhesive strength of the ultraviolet-absorbing layer can be reduced by irradiating the entire ultraviolet-absorbing layer with active energy rays after irradiation with a UV laser. Examples of active energy rays include gamma rays, ultraviolet rays, visible light, infrared rays (thermal rays), radio waves, alpha rays, beta rays, electron beams, plasma streams, ionizing radiation, and particle rays. Ultraviolet rays are preferred. The wavelength of the ultraviolet rays is preferably 300 nm to 400 nm. The irradiation dose is, for example, a cumulative light dose of 300 mJ / cm². 2 ~1500mJ / cm 2 Therefore, if active energy rays are irradiated before laser irradiation, re-attachment can be prevented and the hard substrate can be peeled off.

[0104] The above operation completes the processing of the workpiece. In this invention, the rigid substrate can be peeled off by irradiating the ultraviolet absorption layer with ultraviolet light. The peeling force is low at this time, thus reducing the load applied to the workpiece and preventing damage to the workpiece.

[0105] Example

[0106] (Layering process)

[0107] Semiconductor elements 32 (components 32) are placed on terminals on a rigid wiring circuit board 31 (another rigid substrate 31) to prepare a workpiece 30.

[0108] Using a double-sided adhesive sheet containing an ultraviolet absorption layer 20, the glass substrate 10 (rigid substrate 10) is overlapped onto the semiconductor element 32 and fixed.

[0109] As a double-sided adhesive sheet, a double-sided adhesive sheet is used in which an ultraviolet absorbing layer 20 containing an ultraviolet-curable adhesive is formed on one side of a PI substrate 21, and an adhesive layer 22 is formed on the other side.

[0110] (Processing steps)

[0111] The laminate obtained in the above-mentioned lamination process is clamped by a press, so that the semiconductor element 32 is embedded in the adhesive layer 22 and held.

[0112] Remove the upper plate of the press and irradiate the ultraviolet absorption layer 20 with ultraviolet light (wavelength: 355nm~365nm, cumulative light intensity: 1380mJ / cm²) through the glass substrate 10 (rigid substrate 10). 2 This process cures the ultraviolet absorption layer, thereby reducing the adhesion of the ultraviolet absorption layer to the glass substrate 10 (rigid substrate 10).

[0113] Heating is performed while the semiconductor element 32 (component 32) is being pressed using a press machine to fix the terminal 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.

[0114] (Stripping process)

[0115] Remove the upper plate of the press and irradiate the ultraviolet absorption layer with ultraviolet laser (wavelength: 355nm, irradiation energy: 10J / cm²) through the glass substrate 10 (rigid substrate 10). 2 The glass substrate 10 (rigid substrate 10) is peeled off.

[0116] Next, the double-sided adhesive sheet is peeled off. The semiconductor element 32 (component 32) is undamaged. In addition, the semiconductor element 32 (component 32) does not detach from the rigid wiring circuit substrate 31 (another rigid substrate 31).

[0117] Explanation of reference numerals in the attached figures

[0118] 10. Rigid substrate

[0119] 20 Ultraviolet Absorption Layer

[0120] 30 Workpiece

Claims

1. A member processing method comprising: a lamination step of laminating a hard substrate, an ultraviolet light absorbing layer, and an object to be processed in this order; thereafter, a processing step of processing the object to be processed; and thereafter, a peeling step of peeling the hard substrate from the object to be processed by irradiating the ultraviolet light absorbing layer with UV laser light and irradiating the entire ultraviolet light absorbing layer with active energy rays to reduce the adhesion of the ultraviolet light absorbing layer, the ultraviolet light absorbing layer contains an ultraviolet light absorbing agent, the ultraviolet light absorbing agent is a benzotriazole-based ultraviolet light absorbing agent, a benzophenone-based ultraviolet light absorbing agent, a triazine-based ultraviolet light absorbing agent, a salicylate-based ultraviolet light absorbing agent, or a cyano acrylate-based ultraviolet light absorbing agent.

2. The component processing method according to claim 1, wherein the object to be processed contains another hard substrate and a member disposed on at least one side of the hard substrate.

3. The component processing method according to claim 1, wherein the object to be processed is a semiconductor wafer.

4. The component processing method according to any one of claims 1 to 3, wherein the hard substrate has light transmittance.

5. The component processing method according to any one of claims 1 to 3, wherein the ultraviolet light absorbing layer has adhesion.

6. The component processing method according to any one of claims 1 to 3, wherein the ultraviolet light absorbing layer contains an active energy ray-curable adhesive.

7. The component processing method according to any one of claims 1 to 3, wherein the ultraviolet light absorbing layer contains an ultraviolet light absorbing agent.

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