Composition

Abstract

To provide a composition for provisional fixation that is excellent in compatibility, adaptability to spin coating processes, heat resistance, and adaptability to various peeling processes.SOLUTION: The present invention provides a composition for provisional fixation, containing the components (A) to (C): (A) a bifunctional (meth)acrylate containing no cyclic skeleton; (B) a bifunctional (meth)acrylate having a cyclic skeleton; and (C) a radical photopolymerization initiator.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a temporary fixing composition used for temporary fixing.

Background Art

[0002] An electronic device is obtained by using a substrate made of an inorganic material typified by silicon as a main material and performing processes such as formation of an insulating film, formation of a circuit, and thinning by grinding on its surface. When processing, when using a wafer-type substrate, those with a thickness of about several hundred μm are often used. However, since many substrates are made of a brittle and easily cracked material, particularly when thinning by grinding, measures to prevent breakage are necessary. Conventionally, as this measure, a method of attaching a temporary fixing protective tape that can be peeled off after the completion of the processing step to the surface opposite to the surface to be ground (also referred to as the back surface) has been taken. This tape uses an organic resin film as a base material. While it has flexibility, its strength and heat resistance are insufficient, and it is not suitable for use in processes that reach high temperatures.

[0003] Therefore, a system has been proposed in which an electronic device substrate is bonded to a support such as silicon or glass via an adhesive to impart sufficient durability against the conditions of processes such as back grinding and back electrode formation. What is important at this time is the adhesive layer when bonding the substrate to the support. This requires that the substrate can be bonded to the support without gaps and has sufficient durability to withstand subsequent processes, and finally, the thinned wafer can be easily peeled off from the support.

[0004] The necessary characteristics of the adhesive are as follows: (1) having a viscosity suitable for coating and being a Newtonian fluid (or shear viscosity independent of shear rate), (2) shear adhesive strength capable of withstanding grinding and polishing when thinning the substrate, (3) appropriate hardness to prevent local subsidence of the substrate while dispersing the load in the in-plane direction and maintaining flatness to avoid substrate breakage due to local concentration of the grinding wheel load applied to the substrate during grinding and polishing when thinning the substrate, (4) heat resistance capable of withstanding the formation of the insulating film and the solder reflow process, (5) chemical resistance capable of withstanding thinning and resist processes, (6) easy peelability to easily peel the substrate from the support, (7) aggregation characteristics to prevent adhesive residue from remaining on the substrate after peeling, and (8) easy cleanability.

[0005] As for the adhesive and its peeling method, there have been proposed a technique (Patent Document 1) of peeling the adhesive layer from the support by irradiating a high-intensity light to an adhesive containing a light-absorbing substance to decompose the adhesive layer, and a technique (Patent Document 2) of using a heat-meltable hydrocarbon-based compound as the adhesive and performing bonding and peeling in a heat-melted state. The former technique has problems such as the need for an expensive device such as a laser and a long processing time per substrate. The latter technique is simple because it is controlled only by heating, but the heat stability at a temperature exceeding 200°C is insufficient, so the applicable range is narrow.

[0006] There is disclosed a method for disassembling an adhesive body (Patent Document 3) including a step of irradiating excimer light having a central wavelength of 172 nm or 193 nm to an adhesive body formed by bonding base materials together using an adhesive composition containing one or more (meth)acrylates having one or more (meth)acryloyl groups and curing the adhesive composition, wherein at least one of the base materials is transparent to the excimer light. However, Patent Document 3 does not describe the use of light with a longer wavelength. The present invention does not require the use of excimer light with strong energy for peeling.

[0007] As a resin composition, a technology of an adhesive encapsulation composition for use in electronic devices, which contains a polyisobutene resin and a polyfunctional (meth)acrylate and does not contain a tackifier, has been disclosed (Patent Document 4). Although it is also described that a monofunctional (meth)acrylate is used as a monomer, since the glass transition temperature of the monofunctional (meth)acrylate is not described, there has been a problem that the method for expressing the flexibility required when applying the resin composition as a temporary fixing agent for an electronic device manufacturing process is unknown.

[0008] As a resin composition, a technology of an adhesive encapsulation composition for electronic devices such as organic electroluminescence devices, which contains a monofunctional (meth)acrylate, a polyfunctional (meth)acrylate, and a polyisobutene-based polymer, has also been disclosed (Patent Document 5). However, since the glass transition temperature of the monofunctional (meth)acrylate is not described, there has been a problem that the method for expressing the flexibility required when applying the resin composition as a temporary fixing agent for an electronic device manufacturing process is unknown.

[0009] As a resin composition, a resin composition and an adhesion / disintegration method for adhesion between different substrates, which contain a monofunctional (meth)acrylate, a polyfunctional (meth)acrylate, and an isobutene / maleic anhydride copolymer, have been disclosed (Patent Document 6). However, the polymer in Patent Document 6 is limited in type in that it contains a component derived from maleic anhydride, and the adhesion method is not described in detail. Patent Document 6 does not describe spin coatability such as viscosity.

[0010] A technology of a composite resin composition composed of a urethane (meth)acrylate resin containing an olefin-based polymer structure and a polyisobutylene resin, which can be cured by active energy rays, has been disclosed (Patent Document 7). Also, a photocurable composition containing (A) component: a (meth)acrylate compound having a polyisobutylene skeleton and (B) component: a (meth)acrylamide compound, and containing 0.1 to 15 parts by mass of the (B) component with respect to 100 parts by mass of the (A) component, has been disclosed (Patent Document 8). However, Patent Documents 7 to 8 do not describe temporary fixing applications.

Prior Art Documents

Patent Documents

[0011]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Summary of the Invention

Problems to be Solved by the Invention

[0012] Therefore, for example, even when a composition according to the prior art is used for temporary fixing, problems such as insufficient curing speed, spin-coating process compatibility, heat resistance, low outgassing property under heating and vacuum, and peeling speed, and in particular, insufficient suitability for a UV laser peeling process (peeling step) have not been solved.

Means for Solving the Problems

[0013] That is, the present invention can provide the following aspects.

[0014] [Aspect 1] A temporary fixing composition containing the following (A) to (C). (A) A bifunctional (meth)acrylate not containing a cyclic skeleton (B) A bifunctional (meth)acrylate having a cyclic skeleton (C) A photo radical polymerization initiator

[0015] [Aspect 2] The temporary fixing composition according to aspect 1, further containing the following (D). (D) UV absorber

[0016] [Aspect 3] The temporary fixing composition according to aspect 1 or 2, wherein the molecular weight of component (A) is 250 or more.

[0017] [Aspect 4] The temporary fixing composition according to any one of aspects 1 to 3, wherein component (A) is a bifunctional (meth)acrylate having no alkyl ether skeleton.

[0018] [Aspect 5] The temporary fixing composition according to any one of aspects 1 to 4, wherein component (A) is a bifunctional (meth)acrylate having an aliphatic hydrocarbon skeleton or an aliphatic hydrocarbon skeleton having a hydroxy group and / or an ester skeleton.

[0019] [Aspect 6] The temporary fixing composition according to any one of aspects 1 to 5, wherein component (B) is liquid having a viscosity of 500 mPa·s or more at 23°C or is solid at 23°C.

[0020] [Aspect 7] The temporary fixing composition according to any one of aspects 1 to 6, wherein the cyclic skeleton of component (B) contains an aromatic ring.

[0021] [Aspect 8] The temporary fixing composition according to aspect 7, wherein component (B) has a phenol ether skeleton.

[0022] [Aspect 9] The temporary fixing composition according to aspect 6 or 7, wherein component (B) has a fluorene skeleton.

[0023] [Aspect 10] The provisional fixing composition according to any one of Aspects 1 to 9, wherein the component (C) is a photo radical polymerization initiator that generates radicals with light having a wavelength of 350 nm or more.

[0024] [Aspect 11] (C) component is bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(η 5 -2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)-butan-1-one, 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-O-benzoyloxime, and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetoxyoxime), and is one or more selected from the group consisting of the provisional fixing composition according to any one of Aspects 1 to 10.

[0025] [Aspect 12] The provisional fixing composition according to any one of Aspects 1 to 11, which contains 0.01 to 5 parts by mass of the component (C) with respect to 100 parts by mass in total of the components (A) to (B).

[0026] [Aspect 13] The provisional fixing composition according to any one of Aspects 1 to 12, wherein the mass ratio of the component (A) to the component (B) is in the range of 5 to 95:5 to 95 with respect to 100 parts by mass in total of the components (A) and (B).

[0027] [Aspect 14] The provisional fixing composition according to any one of Aspects 1 to 13, which further contains the following (E). (E) Monofunctional (meth)acrylate

[0028] [Aspect 15] The temporary fixing composition according to aspect 14, containing 0 to 50 parts by mass of component (E) with respect to a total of 100 parts by mass of components (A) and (B).

[0029] [Aspect 16] The temporary fixing composition according to any one of aspects 1 to 13, which does not contain (meth)acrylate other than components (A) and (B).

[0030] [Aspect 17] The temporary fixing composition according to any one of aspects 1 to 16, further containing the following (F). (F) Polymer

[0031] [Aspect 18] The temporary fixing composition according to aspect 17, containing 0 to 50 parts by mass of component (F) with respect to a total of 100 parts by mass of components (A) and (B).

[0032] [Aspect 19] The temporary fixing composition according to any one of aspects 1 to 18, characterized in that the viscosity at 23°C is in the range of 100 to 10,000 mPa·s.

[0033] [Aspect 20] A temporary fixing adhesive containing the temporary fixing composition according to any one of aspects 1 to 19.

[0034] [Aspect 21] An adherend obtained by adhering a substrate using the temporary fixing adhesive according to aspect 20.

[0035] [Aspect 22] A cured body obtained by curing the temporary fixing composition according to any one of aspects 1 to 19.

[0036] [Aspect 23] The cured body according to aspect 22, which is a single-layer cured body.

[0037] [Aspect 24] The cured body according to aspect 22 or 23, wherein the 2% mass loss temperature is 250°C or higher under a nitrogen atmosphere.

[0038] [Aspect 25] The cured body according to any one of Aspects 22 to 24, wherein the 2% mass loss temperature is 250°C or higher in a reduced pressure environment of 30 to 100 Pa.

[0039] [Aspect 26] The following (A) to (C): (A) A bifunctional (meth)acrylate that does not contain a cyclic skeleton (B) A bifunctional (meth)acrylate that has a cyclic skeleton (C) A photo radical polymerization initiator An adhesive body obtained by adhering a substrate using a temporary fixing adhesive containing the above, wherein the temporary fixing adhesive is cured by light having a wavelength of 350 nm or more, and the substrate is peeled off by laser light having a wavelength of less than 385 nm.

[0040] [Aspect 27] Applying the temporary fixing adhesive according to Aspect 20 to a semiconductor wafer substrate and / or a support member, and adhering the semiconductor wafer substrate and the support member; Curing the temporary fixing adhesive by irradiating light having a wavelength of 350 nm to 700 nm to obtain an adhesive body; Irradiating the adhesive body with laser light having a wavelength of less than 385 nm to peel off the semiconductor wafer substrate A method for manufacturing a semiconductor wafer, including the above steps.

[0041] [Aspect 28] The manufacturing method according to Aspect 27, wherein the cured temporary fixing adhesive forms a single layer in the adhesive body.

[0042] [Aspect 29] The temporary fixing adhesive according to Aspect 20, wherein the use is for UV laser peeling.

[0043] [Aspect 30] A first cured layer composed of a temporary fixing composition containing component (A), component (B), and component (C) and not containing component (D), and a second cured layer composed of the temporary fixing composition described in Embodiment 2, and a cured body having different concentration distributions of components in the thickness direction.

[0044] [Aspect 31] A first cured layer obtained by curing the temporary fixing composition described in Embodiment 1 containing component (A), component (B), and component (C), and a second cured layer obtained by applying a UV absorber on the first cured layer, and a cured body having different concentration distributions of components in the thickness direction.

[0045] [Aspect 32] A cured body having a first cured layer obtained by curing the temporary fixing composition described in Embodiment 1 containing component (A), component (B), and component (C), and a photo-thermal conversion (LTHC) cured layer.

[0046] [Aspect 33] A cured body according to any one of Aspects 30 to 32, satisfying all of the following conditions. · Among the light transmittances of the cured body with a thickness of 50 μm, the light transmittance in the wavelength region of 395 nm or more within the wavelengths of the light source used for curing is 70% or more. · Among the light transmittances of the cured body with a thickness of 50 μm, the light transmittance in the wavelength region of 350 nm or more and less than 395 nm within the wavelengths of the light source used for curing is 20% or more. · Among the light transmittances of the cured body with a thickness of 50 μm, the light transmittance at the wavelength (355 nm) of the UV laser used for UV laser peeling is 1% or less.

[0047] [Aspect 34] A structure including a cured body according to any one of Aspects 30 to 33 and an adherend.

[0048] [Aspect 35] A step of applying a temporary fixing composition containing component (A), component (B), and component (C) and not containing component (D) on a wafer and partially curing it, A step of applying the temporary fixing composition described in Embodiment 2 on the partially cured temporary fixing composition. Placing a transparent substrate on the applied temporary fixing composition and subjecting it to photocuring; A method for manufacturing a structure, comprising the above steps.

[0049] [Aspect 36] Applying a temporary fixing composition containing components (A), (B), and (C) and not containing component (D) on a wafer, and partially curing it as necessary; Applying the temporary fixing composition according to Aspect 2 on a transparent substrate, and partially curing it as necessary; Bringing the surfaces of the wafer and the transparent substrate on which the temporary fixing composition is applied into close contact with each other, and then joining them by photocuring; A method for manufacturing a structure, comprising the above steps.

[0050] [Aspect 37] Applying the temporary fixing composition according to Aspect 1 containing components (A), (B), and (C) and not containing component (D) on a wafer, and partially curing it as necessary; Applying a light-to-heat conversion (LTHC) layer on a transparent substrate, drying, and curing it; Bringing the surface of the wafer on which the temporary fixing composition is applied into close contact with the surface of the transparent substrate on which the LTHC layer is applied, and then joining them by photocuring; A method for manufacturing a structure, comprising the above steps. [Advantages of the Invention]

[0051] According to the present invention, for example, a composition excellent in curing rate, spin coating process compatibility, heat resistance, low outgassing property under heating nitrogen atmosphere and reduced pressure, and peeling rate can be obtained, and in addition, a temporary fixing composition suitable for a peeling process, particularly various laser peeling processes (such as UV laser peeling process) can be obtained. [Modes for Carrying Out the Invention]

[0052] The present invention will be described below. In this specification, unless otherwise specified, a numerical range includes its upper and lower limits. Also, amounts and ratios in this specification are based on mass unless otherwise specified.

[0053] A monofunctional (meth)acrylate refers to a compound having one (meth)acryloyl group in one molecule. A difunctional (meth)acrylate refers to a compound having two (meth)acryloyl groups in one molecule, and in this specification, it is distinguished from other polyfunctional (meth)acrylates and monofunctional (meth)acrylates. Note that in this specification, a polyfunctional (meth)acrylate refers to a compound having two or more (meth)acryloyl groups in one molecule, but it should be noted that difunctional (meth)acrylates may be excluded depending on the context.

[0054] Unless otherwise specified, in this specification, polymerizable compounds such as (meth)acrylates mean monomers, and those obtained by polymerizing them are referred to as polymers.

[0055] The temporary fixing composition according to an embodiment of the present invention (hereinafter, may be simply referred to as "composition") is characterized by containing the following components (A) to (C). It is preferable that the composition does not contain (meth)acrylates other than components (A) and (B). (A) A difunctional (meth)acrylate not containing a cyclic skeleton (B) A difunctional (meth)acrylate having a cyclic skeleton (C) A photo radical polymerization initiator

[0056] When difunctional (meth)acrylates are used as the above components (A) and (B), unlike the case where other (meth)acrylates are used, the reactivity and crosslinkability are appropriate, so the resulting composition exhibits excellent heat resistance. Furthermore, the inventor of the present invention conceived that the combination of component (A) having no cyclic skeleton and component (B) having a cyclic skeleton significantly improves the performance as a temporary fixing agent, and completed the present invention.

[0057] The composition according to a certain embodiment may not contain (meth)acrylates other than bifunctional (meth)acrylates. The composition according to another embodiment may contain (meth)acrylates other than bifunctional (meth)acrylates (for example, monofunctional (meth)acrylates or trifunctional (meth)acrylates) as long as the effects of the present invention are not impaired, and the amount thereof may be more than 0 part by mass and 50 parts by mass or less when the total of component (A) and component (B) is 100 parts by mass.

[0058] The bifunctional (meth)acrylate containing no cyclic skeleton, which is component (A), refers to one having neither an alicyclic skeleton nor an aromatic ring skeleton. As component (A), a bifunctional (meth)acrylate having a linear alkyl group or a branched alkyl group is preferable. The alkyl group may have a substituent and may be, for example, a hydroxyalkyl group.

[0059] Examples of component (A) include 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, neopentyl glycol-modified trimethylolpropane di(meth)acrylate, stearic acid-modified pentaerythritol di(meth)acrylate, tripropylene glycol di(meth)acrylate, hydroxypivalyl hydroxypivalate bis[6-(acryloyloxy)hexanoate] (abbreviation: HPHPAH), di(meth)acrylate of an ε-caprolactone adduct of hydroxypivalic acid neopentyl glycol (for example, trade names KAYARAD HX-220, HX-620, etc. manufactured by Nippon Kayaku Co., Ltd.), and compounds having no alkyl ether skeleton.

[0060] In a preferred embodiment, from the viewpoint of moderately increasing the viscosity of the resulting composition, the molecular weight of component (A) may be 250 or more, more preferably 300 or more, and even more preferably 500 or more. The upper limit of the molecular weight of component (A) is not particularly limited, but from the viewpoint of not excessively increasing the viscosity of the composition, it may be, for example, 2000 or less, preferably 1000 or less. Component (A) is, for example, preferably a branched-chain alkyl group having 18 to 40 carbon atoms, more preferably 18 to 32 carbon atoms, such as an isostearyl group, an isotetracosanyl group (such as 2-decyl-1-tetradecanyl group), an isotriacontanyl group (such as 2-tetradecyl-1-octadecanyl group), etc. By using such a component having a long chain, high molecular weight, and strong aliphatic hydrocarbon character, properties such as low volatility, chemical resistance, and heat resistance required for the temporary fixing composition can be improved.

[0061] In a preferred embodiment, component (A) may be a polyhydric alcohol (more preferably a dihydric or trihydric alcohol), or a di(meth)acrylate derived from an alkyl ester. More specifically, component (A) may have an aliphatic hydrocarbon skeleton or an aliphatic hydrocarbon skeleton having a hydroxy group (preferably composed of a linear or branched aliphatic hydrocarbon having (meth)acryloyl groups at both ends), or may have an ester skeleton (preferably composed of an aliphatic ester having (meth)acryloyl groups at both ends), or may have both of these characteristics.

[0062] In a preferred embodiment, from the viewpoint of improving heat resistance, component (A) may have a structure without an alkyl ether skeleton. By combining component (A) without an alkyl ether skeleton with component (B) having a phenol ether skeleton described later, an effect of excellent improvement in the heat resistance of the composition can be obtained.

[0063] (B) The difunctional (meth)acrylate having a cyclic skeleton, which is a component, is a compound having one or more ring structures, and the ring may be a carbocyclic ring, a heterocyclic ring, or a combination thereof. In a preferred embodiment, from the viewpoint of improving heat resistance, the component (B) may have one or more aromatic rings, more preferably a plurality of aromatic rings, and even more preferably a condensed aromatic ring (for example, having a fluorene skeleton, a naphthalene skeleton, an indene skeleton, an anthracene skeleton, etc.).

[0064] In a preferred embodiment, when the component (B) has a spiro ring structure, a remarkable effect can be obtained in which excellent viscosity can be obtained in the composition while excellent outgassing properties and heat resistance can be achieved at the same time. Examples of such a component (B) include bisphenol fluorene derivatives (for example, 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene diacrylate, etc.), biscresol fluorene derivatives, cycloalkane derivatives (cyclodecane derivatives, cyclooctane derivatives, etc.).

[0065] In a preferred embodiment, when the component (B) has a phenol ether skeleton, the heat resistance can be improved in combination with the above-described component (A).

[0066] The molecular weight of the component (B) is not particularly limited, but from the viewpoint of moderately increasing the viscosity of the composition, it may be, for example, 200 or more, more preferably 300 or more, and even more preferably 500 or more. The upper limit of the molecular weight of the component (B) is not particularly limited, but from the viewpoint of not increasing the viscosity of the composition too much, it may be, for example, 2000 or less, preferably 1000 or less. The component (B) is preferably liquid having a viscosity of 500 mPa·s or more at 23°C, or may be solid at 23°C.

[0067] In a preferred embodiment, it is preferable from the viewpoint of improving outgassing properties that the component (B) has an aromatic ring and the number of carbon atoms in the alkyl chain portion is small (that is, the ratio of the aliphatic moiety to the aromatic ring is small). For example, the number of carbon atoms in the alkyl chain portion of the component (B) may be 20 or less, more preferably 10 or less, and even more preferably 5 or less.

[0068] Examples of the component (B) include 1,3-di(meth)acryloyloxyadamantane, dicyclopentanyl di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, 2,2-bis(4-(meth)acryloxydiethoxyphenyl)propane, 2,2-bis(4-(meth)acryloxypropoxyphenyl)propane, 2,2-bis(4-(meth)acryloxytetraethoxyphenyl)propane, ethylene oxide-modified di(meth)acrylate of isocyanuric acid, and di(meth)acrylate having a fluorene skeleton (for example, 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene di(meth)acrylate, etc.). Examples of the di(meth)acrylate having a fluorene skeleton include those commercially available as A-BPEF-2 manufactured by Shin-Nakamura Chemical Co., Ltd., OGSOL GA-5060P, EA-0300, GA-5060P, and GA-2800 manufactured by Osaka Gas Chemical Co., Ltd.

[0069] Another example of the component (B) includes ethoxylated bisphenol A di(meth)acrylate represented by the following formula (1).

Chemical formula

[0070] (A) and (B) components, from the viewpoint of spin coating process compatibility, preferably have a mass ratio in the range of 5 to 95:5 to 95, more preferably in the range of 25 to 75:25 to 75, and even more preferably in the range of 33 to 67:33 to 67, based on 100 parts by mass in total.

[0071] (C) The photo radical polymerization initiator means a compound in which molecules are cleaved upon irradiation with ultraviolet or visible light (for example, wavelength 350 nm to 700 nm, preferably 385 nm to 700 nm, more preferably 385 nm to 500 nm, and even more preferably 385 nm to 450 nm) and split into two or more radicals.

[0072] (C) As the photo radical polymerization initiator, in terms of having absorption characteristics in a region different from both the wavelength of the UV laser used for UV laser peeling described later and the absorption wavelength region of the UV absorber used for the UV laser peeling, and also in terms of reaction rate, heat resistance after curing, and low outgassing property, one or more selected from acylphosphine oxide-based compounds, titanocene-based compounds, or α-aminoalkylphenone-based compounds are preferred. Also, for the photo radical polymerization initiator for the resin composition for temporary fixing use for preventing breakage from the bonding of the base material to be processed with the support base material to the heating process, which is not the layer corresponding to the UV laser peeling process among the temporary fixing compositions having the structure described later, an oxime ester-based compound can also be selected in addition to the above.

[0073] Examples of acylphosphine oxide-based compounds include bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, etc. Among these, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide is particularly preferred.

[0074] Examples of titanocene-based compounds include bis(η 5 -2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium.

[0075] Examples of the α-aminoalkylphenone compounds include 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)-butan-1-one, and the like.

[0076] Examples of the oxime ester compounds include 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-O-benzoyloxime, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetoxyoxime), and the like. Among these, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetoxyoxime) is preferred.

[0077] (C) As the photoinitiator, at least one selected from the group consisting of bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(η 5 -2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)-butan-1-one, 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-O-benzoyloxime, and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetoxyoxime) is preferred.

[0078] When providing a temporary fixing composition for the UV laser peeling process of the present invention, the most preferred photo radical polymerization initiator is an acylphosphine oxide-based compound. Preferred acylphosphine oxide-based compounds are bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and / or 2,4,6-trimethylbenzoyldiphenylphosphine oxide. These photo radical polymerization initiators are highly sensitive, have excellent deep part curability due to having photo fading properties, and in addition, the absorption wavelength region for generating radicals extends to a relatively long wavelength region. Specifically, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide ranges up to a wavelength of about 440 nm, and there is a large difference from the absorption wavelength region of the UV absorber used in the UV laser peeling process described later. That is, the degree of inhibition of UV curing by the added UV absorber is small, and radical polymerization can be initiated with light of a longer wavelength. Therefore, even in the coexistence of a UV absorber, radical polymerization can be efficiently initiated at a relatively high speed and cured.

[0079] Most preferably, the photo radical polymerization initiator can be selected from absorbance. Specifically, when dissolved at a concentration of 0.1% by mass in a solvent having no maximum absorption in the wavelength range of 300 nm to 500 nm (for example, acetonitrile, toluene, etc.), the absorbance at a wavelength of 365 nm is 0.5 or more, the absorbance at a wavelength of 385 nm is 0.5 or more, and the absorbance at a wavelength of 405 nm is 0.5 or more. The photo radical polymerization initiator can be selected from one or more compounds that satisfy any one or more of these conditions. Examples of compounds that satisfy such conditions include 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetoxyoxime) having an absorbance of 0.5 or more at a wavelength of 365 nm when dissolved at a concentration of 0.1% by mass with respect to acetonitrile as a solvent, 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-O-benzoyloxime having an absorbance of 0.5 or more at wavelengths of 365 nm and 385 nm, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide having an absorbance of 0.5 or more at wavelengths of 365 nm, 385 nm, and 405 nm.

[0080] Also, from the viewpoint of achieving both curability by the photo radical polymerization initiator and UV laser peelability, bis(η 5 -2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium having an absorption wavelength region in the range of 400 to 500 nm can also be used as the photo radical polymerization initiator.

[0081] (C) The amount of the photo radical polymerization initiator used is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 1 part by mass, based on 100 parts by mass in total of (A) to (B) in terms of reaction rate, heat resistance after curing, and low outgassing property. When the amount of component (C) is 0.01 part by mass or more, sufficient curability can be obtained, and when it is 5 parts by mass or less, there is no risk of impairing low outgassing property and heat resistance.

[0082] The UV absorber that can be used as the component (D) that the present composition may contain is, for example, a compound in which molecules are cleaved by irradiation with ultraviolet rays or a laser of visible light, decomposed and vaporized, and the decomposition and vaporization occur at the interface between the support substrate (or support) and the temporary fixing agent, thereby losing the adhesive force between the temporary fixing agent and the support substrate (or support) that was maintained until immediately before the peeling step.

[0083] (D) As the UV absorber, one or more selected from benzotriazole compounds and hydroxyphenyltriazine compounds are preferable in terms of the degree of overlap with the UV laser wavelength in the UV absorption wavelength region, UV absorption characteristics at the same wavelength, low outgassing property, and heat resistance.

[0084] As the benzotriazole compound, one or more selected from the group consisting of 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol, 2,2'-methylenebis[6-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol], 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol, and 2-[2-hydroxy-3-(3,4,5,6-tetrahydrophthalimidomethyl)-5-methylphenyl]benzotriazole are particularly preferable in terms of compatibility with the resin component, UV absorption characteristics, low outgassing property, and heat resistance.

[0085] As the hydroxyphenyltriazine compound, one or more selected from the group consisting of 2-[4-[(2-hydroxy-3-(2'-ethyl)hexyloxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2,4-bis(2-hydroxy-4-butyloxyphenyl)-6-(2,4-bis-butyloxyphenyl)-1,3,5-triazine, and 2,4,6-tris(2-hydroxy-4-hexyloxy-3-methylphenyl)-1,3,5-triazine are particularly preferable in terms of compatibility with the resin component, UV absorption characteristics, low outgassing property, and heat resistance.

[0086] When providing the temporary fixing composition for the UV laser peeling process of the present invention, the most preferred UV absorbers are one or more selected from the group consisting of 2,4,6-tris(2-hydroxy-4-hexyloxy-3-methylphenyl)-1,3,5-triazine, 2,4-bis(2-hydroxy-4-butyloxyphenyl)-6-(2,4-bis-butyloxyphenyl)-1,3,5-triazine, or 2,2'-methylenebis[6-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol]. These are excellent in compatibility with components (A) to (B), have a high melting point, and have a relatively low vapor pressure under temperature conditions of about 300 °C or lower. Therefore, they can be selected within a wide range of usage amounts and can contribute to reducing outgassing under this temperature condition from the cured temporary fixing composition.

[0087] (D) As the UV absorber, most preferably, an absorber selected from the UV transmittance can be used. Since component (D) has such a UV transmittance, an effect of appropriately controlling the curing and peeling of the composition can be obtained.

[0088] When the UV absorber is dissolved at a concentration of 0.002% by mass in a solvent having no maximum absorption at a wavelength of 290 to 410 nm, the transmittance at a wavelength of 355 nm with an optical path length of 1 cm is preferably 50% or less, and the transmittance is higher than 50% at a wavelength of 385 to 420 nm. More preferably, the transmittance at a wavelength of 355 nm is 40% or less, and the transmittance at 385 to 420 nm may be 60% or more.

[0089] Examples of the most preferred (D) UV absorber include the following.

[0090] 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol (Tinuvin 900 manufactured by BASF, Adeka Stab LA-24 manufactured by Adeka Corporation, EVERSORB 76 and EVERSORB 234 manufactured by Everlight Chemical, molecular weight 447), which has a transmittance of 20% or less at a wavelength of 355 nm with an optical path length of 1 cm and a transmittance of 60% or more at wavelengths of 385 to 420 nm when dissolved at a concentration of 0.002% by mass in toluene used as a solvent.

[0091] 2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol (Tinuvin 928 manufactured by BASF, EVERSORB 89 / 89FD manufactured by Everlight Chemical, molecular weight 442), which has a transmittance of 30% or less at a wavelength of 355 nm with an optical path length of 1 cm and a transmittance of 70% or more at wavelengths of 385 to 420 nm when dissolved at a concentration of 0.002% by mass in toluene used as a solvent.

[0092] 2-[4-[(2-hydroxy-3-(2'-ethyl)hexyloxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine (Tinuvin 405 manufactured by BASF, molecular weight 584), which has a transmittance of 40% or less at a wavelength of 355 nm with an optical path length of 1 cm and a transmittance of 90% or more at wavelengths of 385 to 420 nm when dissolved at a concentration of 0.002% by mass in tetrahydrofuran used as a solvent.

[0093] 2,4-bis(2-hydroxy-4-butyloxyphenyl)-6-(2,4-bis-butoxyphenyl)-1,3,5-triazine (Tinuvin 460 manufactured by BASF, molecular weight 630), which has a transmittance of 10% or less at a wavelength of 355 nm with an optical path length of 1 cm and a transmittance of 80% or more at wavelengths of 385 to 420 nm when dissolved at a concentration of 0.002% by mass in tetrahydrofuran used as a solvent.

[0094] The UV transmittance of the cured body in this specification is a value obtained by reflectance measurement spectroscopy. Specifically, the transmittance is obtained using a reflectance spectroscopic measuring device (V-650 manufactured by JASCO Corporation) with a film of the cured body having a thickness of about 50 μm formed by sandwiching it between sheets of PET resin under the following conditions.

[0095] Cell length: 10 mm Measurement mode: T (Transmittance) Measurement range: 450 - 200 nm Data acquisition interval: 1 nm UV / vis bandwidth: 2.0 nm Response: medium Scanning speed: 40 nm / min Light source switching: 340 nm Light source: D2 / WI Filter switching: step Correction: baseline

[0096] The amount of the UV absorber as the component (D) is preferably 0.01 to 5 parts by mass, more preferably 0.5 to 2.5 parts by mass, based on 100 parts by mass in total of (A) to (B). If it is 0.01 part by mass or more, a sufficient UV laser peeling rate can be obtained, and if it is 5 parts by mass or less, there is no risk of impairing low outgassing property and heat resistance.

[0097] A composition having such characteristics can be suitably used in a process including a high-temperature vacuum process such as ion implantation, annealing, or electrode formation by sputtering in the back surface process after thinning.

[0098] The viscosity of the composition according to the embodiment of the present invention is preferably in the range of 100 to 10000 mPa·s, more preferably in the range of 560 to 9200 mPa·s, and even more preferably in the range of 1100 to 6400 mPa·s at 23 °C (under atmospheric pressure).

[0099] The outgassing property of the cured product of the composition according to the embodiment of the present invention can be evaluated by the 2% mass loss temperature. The 2% mass loss temperature of the cured product in a nitrogen atmosphere is preferably 250 °C or higher, more preferably 270 °C or higher, and even more preferably 300 °C or higher. The 2% mass loss temperature of the cured product in an environment where the pressure is reduced to 30 to 100 Pa is preferably 150 °C or higher, more preferably 200 °C or higher, and even more preferably 250 °C or higher.

[0100] In this specification, the 2% mass loss temperature can be evaluated by a combination of a plurality of conditions. In the technical field, it is known that the 2% mass loss temperatures measured in different environments are generally not interchangeable. That is, it is known that the value in another environment cannot be easily inferred from the 2% mass loss temperature in a certain environment.

[0101] Further, when a cured film with a thickness of 50 μm is produced using the temporary fixing composition of the present invention, it is preferable to satisfy one or more of the following conditions, and more preferably to satisfy all of the following conditions. The following conditions can be satisfied, for example, by using the above-mentioned UV absorber and photoinitiator for free radical polymerization. · Among the light transmittances of the cured film, the light transmittance in the wavelength region of 395 nm or more within the wavelengths of the light source used for curing is 70% or more. · Among the light transmittances of the cured film, the light transmittance in the wavelength region of 350 nm or more and less than 395 nm, preferably 385 nm or more and less than 395 nm within the wavelengths of the light source used for curing is 20% or more. · Among the light transmittances of the cured film, the light transmittance at the wavelength (355 nm) of the UV laser used for UV laser peeling is 1% or less. By satisfying these conditions, it is possible to achieve both a practically sufficiently high curing rate and a UV laser peeling rate. Furthermore, in addition to achieving both a sufficiently high curing rate and a UV laser peeling rate, it is possible to reduce the rate of mass loss under the heating conditions after curing (or reduce the outgassing amount under high temperature vacuum). A temporary fixing agent having such characteristics can be suitably used in a process including a high temperature vacuum process such as ion implantation, annealing, or electrode formation by sputtering in the back surface process after thinning.

[0102] In order to maintain the peelability after exposure to high temperatures, an antioxidant may be used in the composition of the present invention. Examples of the antioxidant include methylhydroquinone, hydroquinone, 2,2 - methylene - bis(4 - methyl - 6 - tertiary butylphenol), catechol, hydroquinone monomethyl ether, monoter tiary butylhydroquinone, 2,5 - ditertiary butylhydroquinone, p - benzoquinone, 2,5 - diphenyl - p - benzoquinone, 2,5 - ditertiary butyl - p - benzoquinone, picric acid, citric acid, phenothiazine, tertiary butylcatechol, 2 - butyl - 4 - hydroxyanisole, 2,6 - ditertiary butyl - p - cresol, and 4 - ((4,6 - bis(octylthio)-1,3,5 - triazin - 2 - yl)amino)-2,6 - di - t - butylphenol.

[0103] The amount of the antioxidant used is preferably 0.001 to 3 parts by mass with respect to a total of 100 parts by mass of (A) to (D). If it is 0.001 part by mass or more, the maintenance of peelability after exposure to high temperatures is ensured, and if it is 3 parts by mass or less, good adhesiveness can be obtained and it will not become uncured.

[0104] In the composition according to an embodiment, a monofunctional (meth)acrylate may be further added as component (E), and the addition amount may be more than 0 part by mass and 50 parts by mass or less of component (E) with respect to a total of 100 parts by mass of components (A) to (B).

[0105] (E) component examples preferably include (meth) acrylates having a linear or branched alkyl group. Such compounds include, for example, ethyl (meth) acrylate, butyl (meth) acrylate, stearyl (meth) acrylate, isostearyl (meth) acrylate, nonadecyl (meth) acrylate, eicosadecyl (meth) acrylate, behenyl (meth) acrylate, 2-decyl-1-tetradecanyl (meth) acrylate, 2-tetradecyl-1-octadecanyl (meth) acrylate, and the like.

[0106] In the composition according to an embodiment, a polymer may be further added as the (F) component, and the addition amount may be more than 0 parts by mass and 50 parts by mass or less of the (F) component with respect to 100 parts by mass in total of the (A) to (B) components. The (F) component desirably has a property of not inhibiting the light transmittance of the cured product of the composition.

[0107] Examples of the (F) component include polymers made from polyvinyl chloride, polyethylene, polypropylene, ethylene-vinyl acetate copolymer, vinyl acetate, modified vinyl acetate, etc., vinyl acetate-(meth) acrylic copolymer, styrene-(meth) acrylic copolymer, vinyl acetate-(meth) acrylate copolymer, (meth) acrylic-silicone copolymer, (meth) acrylic-urethane copolymer, natural rubber, synthetic rubber, etc. From the viewpoint of improving heat resistance, those having a glass transition temperature of 300°C or lower (such as polyisobutene) are preferably added in a small amount (for example, 5 parts by mass or less with respect to 100 parts by mass in total of the (A) to (B) components), and it is more preferable not to add them.

[0108] As the coating method of the present composition, known coating methods such as spin coating, screen printing, and various coaters can be used. In terms of coatability and workability, the viscosity of the composition of the present invention is preferably 100 mPa·s or more, more preferably 1000 mPa·s or more, and most preferably 2000 mPa·s or more. In terms of coatability and workability, the viscosity of the composition of the present invention is preferably 10000 mPa·s or less, more preferably 5000 mPa·s or less, and most preferably 4000 mPa·s or less. When it is 100 mPa·s or more, the coatability, particularly the coatability by spin coating, is excellent. When it is 10000 mPa·s or less, the workability is excellent.

[0109] Spin coating is, for example, a method of applying a liquid composition onto a substrate by dropping the liquid composition onto the substrate and rotating the substrate at a predetermined rotational speed. High-quality coating films can be efficiently produced by spin coating.

[0110] The composition of the present invention can be used as a temporary fixing resin composition, a temporary fixing adhesive, an adhesive sheet, or a temporary fixing adhesive for manufacturing electronic devices. In the present invention, the temporary fixing composition, the temporary fixing resin composition, and the temporary fixing adhesive may be collectively referred to as the temporary fixing agent.

[0111] When adhering a substrate to be processed and an optically transparent support substrate (or support) using the composition of the present invention, it is preferably irradiated so that the energy amount is 1 to 20000 mJ / cm 2 at visible light or ultraviolet light (wavelength or central wavelength 365 - 405 nm). When the energy amount is 1 mJ / cm 2 or more, sufficient adhesiveness can be obtained. When it is 20000 mJ / cm 2 or less, the productivity is excellent, decomposition products from the photo radical polymerization initiator are less likely to be generated, and the generation of outgas is suppressed. In terms of productivity, adhesiveness, low outgas property, and easy peelability, it is preferably 1000 - 10000 mJ / cm 2 .

[0112] The substrate adhered by the composition of the present invention is not particularly limited, but at least one of the substrates is preferably a transparent substrate that transmits light. Examples of the transparent substrate include inorganic substrates such as crystal, glass, quartz, calcium fluoride, and magnesium fluoride, and organic substrates such as plastics. Among these, inorganic substrates are preferred in terms of versatility and large effects. Among the inorganic substrates, one or more selected from glass and quartz are preferred.

[0113] In one embodiment, the composition of the present invention is photocurable, and the cured body provided thereby has excellent heat resistance and peelability. In one embodiment, the cured body of the composition of the present invention has a small outgassing amount even when exposed to high temperatures, and is suitable for bonding, sealing, and coating various optical components, optical devices, and electronic components. The composition of the present invention is suitable for applications that require a wide range of durability such as solvent resistance, heat resistance, and adhesiveness, particularly for semiconductor manufacturing process applications.

[0114] The cured body of the composition of the present invention can be used in processes in a wide temperature range from room temperature to high temperature. The heating temperature during the process is preferably 350°C or lower, more preferably 300°C or lower, and most preferably 250°C or lower. The adhered body adhered with the temporary fixing adhesive of the present invention has a high shear adhesive force and can withstand thinning processes and the like, and can be easily peeled off after undergoing heating processes such as insulating film formation. When used at high temperatures, the cured body of the composition of the present invention can be used, for example, in a high-temperature process of preferably 200°C or higher, more preferably 250°C or higher.

[0115] Furthermore, in one embodiment of the present invention, an adhered body in which a substrate is adhered with a temporary fixing adhesive is obtained, and an effect of being peeled off can be obtained by applying an external force to the adhered body. For example, it can be peeled off by inserting a blade, a sheet, or a wire into the joint portion.

[0116] Furthermore, in one embodiment of the present invention, an adhesive body in which a substrate is adhered with a temporary fixing adhesive is obtained, and an effect of being able to be peeled off is obtained by irradiating the entire surface with a UV laser or an IR laser from the optically transparent substrate side of the adhesive body.

[0117] <Method for manufacturing a thin wafer> In an embodiment of the present invention, a method for manufacturing a thin wafer can also be provided. The manufacturing method is characterized in that the above-described temporary fixing composition or temporary fixing adhesive (hereinafter, sometimes simply referred to as an adhesive or a temporary fixing agent) is used as an adhesive layer between a wafer having a semiconductor circuit or the like and a support. The method for manufacturing a thin wafer of the present invention has the following steps (a) to (e).

[0118] [Step (a)] In step (a), when joining the circuit formation surface of a wafer having a circuit formation surface on the front surface and a circuit non-formation surface on the back surface to a support via an adhesive, the adhesive is applied on the support or the wafer with a circuit by a spin coating method, and it is a step of bonding with the other support or the wafer with a circuit under vacuum.

[0119] A wafer having a circuit formation surface and a circuit non-formation surface is a wafer having one surface as a circuit formation surface and the other surface as a circuit non-formation surface. The wafer to which the present invention can be applied is usually a semiconductor wafer. Examples of the semiconductor wafer include not only silicon wafers but also gallium nitride wafers, lithium tantalate wafers, lithium niobate wafers, silicon carbide wafers, germanium wafers, gallium-arsenic wafers, gallium-phosphorus wafers, gallium-arsenic-aluminum wafers, and the like. The thickness of the wafer is not particularly limited, but is preferably 600 to 800 μm, and more preferably 625 to 775 μm. As the support, for example, a transparent substrate that transmits light is used.

[0120] [Step (b)] Step (b) is a step of photocuring the adhesive. After the wafer processed body (laminated body substrate) is formed, the energy amount is 1 to 20000 mJ / cm in the visible light or ultraviolet ray (wavelength or center wavelength 365 nm to 405 nm) region2 It is preferably irradiated so as to achieve this. When the energy amount is 1 mJ / cm 2 or more, sufficient adhesiveness can be obtained. When it is 20000 mJ / cm 2 or less, productivity is excellent, decomposition products from the photo radical polymerization initiator are less likely to be generated, and generation of outgas is also suppressed. In terms of productivity, adhesiveness, low outgas property, and easy peelability, 1000 to 10000 mJ / cm 2 is more preferable.

[0121] In the curing of the composition, a black light, UV-LED, or visible light-LED can be used as the light source, and for example, the following light sources can be used. As the black light, regardless of its central wavelength, light containing a component with a wavelength of 350 nm or more, preferably 385 nm or more, is preferably used. When the wavelength range is described in this specification, it is determined whether the central wavelength is included in the range to determine whether it is included in the range. · Black light (central wavelength 365 nm, illuminance 10 mW / cm 2 , manufactured by Toyo Adtech Co., Ltd., TUV-8271) · UV-LED (wavelength 385 ± 5 nm, illuminance 350 mW / cm 2 (Condition: Work distance from the tip of the mirror unit is 20 mm), dedicated design mirror unit manufactured by HOYA Corporation, H-4MLH200-V2-1S19+) · UV-LEDz (wavelength 395 ± 5 nm, illuminance 375 mW / cm 2 (Condition: Work distance from the tip of the mirror unit is 20 mm), dedicated design mirror unit manufactured by HOYA Corporation, H-4MLH200-V3-1S19+) · UV-LED (wavelength 405 ± 5 nm, illuminance 400 mW / cm 2 (Condition: Work distance from the tip of the mirror unit is 20 mm), dedicated design mirror unit manufactured by HOYA Corporation, H-4MLH200-V4-1S19+) · UV-LED (central wavelength 405 nm, illuminance 10 mW / cm 2 , manufactured by CCS, HLDL-120V0-NWPSC) · Visible light-LED (wavelength 451 ± 5 nm, illuminance 550 mW / cm 2 (Condition: working distance from the tip of the irradiation unit is 10 mm), HLDL-155VL450-PSC manufactured by CCS Co., Ltd.) · Visible light-LED (wavelength 492 ± 5 nm, illuminance 400 mW / cm 2 (Condition: working distance from the tip of the irradiation unit is 10 mm), HLDL-155BG-PSC manufactured by CCS Co., Ltd.)

[0122] In a preferred embodiment, since the irradiation wavelength is generally broad, the integrated light quantity is large and the irradiation time tends to be long. Therefore, it is preferable to use a UV-LED or visible light-LED that requires less integrated light quantity (less irradiation time) than black light. That is, by using an LED light source with a narrow irradiation wavelength, temporary fixing can be performed in a short time, and as a result, the effect of shortening the time required for the manufacturing process can be obtained.

[0123] [Step (c)] Step (c) is a step of grinding and / or polishing the non-circuit-forming surface of the wafer bonded to the support, that is, a step of grinding the back side of the wafer of the wafer processed body obtained by bonding in step (a) to reduce the thickness of the wafer. The thickness of the thinned wafer is preferably 10 to 300 μm, more preferably 30 to 100 μm. There is no particular limitation on the method of grinding / polishing the back side of the wafer, and a known grinding / polishing method is adopted. Grinding is preferably performed while cooling by applying water to the wafer and the grinding wheel (such as a grinding wheel with a diamond blade).

[0124] [Step (d)] Step (d) is a step of processing the non-circuit forming surface of the wafer workpiece that has been ground / polished, i.e., the non-circuit forming surface of the wafer workpiece thinned by back grinding / polishing. This step includes various processes used at the wafer level. For example, electrode formation, metal wiring formation, protective film formation, etc. More specifically, metal sputtering for forming electrodes, wet etching for etching the metal sputtering layer, application of resist to serve as a mask for metal wiring formation, exposure, and pattern formation by development, resist stripping, dry etching, formation of metal plating, silicon etching for TSV formation, formation of an oxide film on the silicon surface, etc., are conventional well-known processes.

[0125] [Step (e)] Step (e) is a peeling step. This step is to peel the wafer processed in step (d) from the wafer workpiece. For example, it is a step of peeling the wafer from the wafer workpiece after various processes are performed on the thinned wafer and before dicing. At this time, a dicing tape can be attached to the surface that has been thinned and processed in advance. This peeling step is generally carried out under relatively low temperature conditions from room temperature to about 60°C. As this peeling step, any of the known UV laser peeling step, IR laser peeling step, or mechanical peeling step can be adopted. Preferably, the UV laser peeling step can be used.

[0126] The UV laser peeling step is, for example, a step of irradiating the entire surface with a UV laser so as to scan linearly back and forth in a tangential direction from the end on the optically transparent support side of the wafer workpiece, and decomposing the adhesive layer by the energy of the laser to perform peeling. Such a peeling step is described, for example, in Japanese Patent Application Laid-Open No. 2019-501790 and Japanese Patent Application Laid-Open No. 2016-500918. The temporary fixing composition of the present invention particularly contains the component (D) and is particularly suitable for the UV laser peeling step by satisfying the preferable requirements of the component (C) and / or the component (D).

[0127] The IR laser peeling process is, for example, a process in which an IR laser is irradiated over the entire surface so as to scan linearly back and forth in a tangential direction from the end on the optically transparent support side of the wafer processed body, and the adhesive layer is heated and decomposed by the energy of the laser to effect peeling. Such a peeling process is described, for example, in Japanese Patent No. 4565804. To carry out this IR laser peeling process, a photothermal conversion layer (for example, 3M's LTHC; Light-To-Heat-Conversion release coating) that absorbs IR laser light and converts it into heat may be provided between the temporary fixing agent layer and the glass support. When using 3M's LTHC, for example, LTHC is spin-coated on the glass support and cured, and the temporary fixing agent layer is spin-coated on the wafer and then bonded to the glass support on which the LTHC layer has been formed and UV-cured. A method for carrying out the IR laser peeling process using 3M's LTHC is described, for example, in the same Japanese Patent No. 4565804 as above.

[0128] The mechanical peeling process is, for example, a peeling process including a process in which a blade is inserted into the interface end of the wafer processed body, the wafer of the wafer processed body is horizontally fixed with the wafer on the lower side to generate a cleavage between the wafer and the support, and after the blade is inserted, an upward stress is applied to the upper support and / or the blade to advance the cleavage and peel the wafer and the support. Such a peeling process is described, for example, in Japanese Patent No. 6377956 and Japanese Unexamined Patent Application Publication No. 2016-106404.

[0129] In peeling the composition according to the embodiment of the present invention, any of these peeling methods can be used. At this time, one of the wafer or the support of the wafer processed body is fixed horizontally, and then a blade is inserted or a solvent (for example, aliphatic or aromatic hydrocarbon solvents such as pentane, hexane, heptane, octane, nonane, decane, benzene, toluene, xylene, mesitylene, etc.) is used to swell the outer peripheral portion of the adhesive layer to create a trigger for peeling, and then the other is lifted at a certain angle from the horizontal direction. These peeling methods are usually carried out at room temperature, but it is also preferable to heat to about 90°C at the upper limit. When using a laser, it is preferable to use a YAG laser or a YVO4 laser.

[0130] The step of peeling the wafer processed in the above step (e) from the support, in the case of a mechanical peeling step, further (f) A step of adhering a dicing tape to the wafer surface of the processed wafer; (g) A step of vacuum-sucking the dicing tape surface onto the suction surface; (h) A step of peeling the support from the processed wafer in a temperature range where the temperature of the suction surface is 10 to 100°C; is preferably included. By doing so, the support can be easily peeled from the processed wafer, and the subsequent dicing step can be easily performed.

[0131] Also, when peeling with a UV laser or an IR laser, the manufacturing method further includes, for example, (i) A step of placing / fixing the processed wafer with the optically transparent support side facing up in a horizontal place, preferably via a dicing tape; (j) A step of irradiating the entire surface of the processed wafer from the support side with a laser so as to scan; is preferably included. By doing so, the support can be easily peeled from the processed wafer, and the subsequent dicing step can be easily performed.

[0132] Next to the step of peeling the wafer processed in step (e) from the support by a UV laser or an IR laser, (k) a step of removing the temporary fixing agent remaining on the surface of the wafer, needs to be carried out. As a method for removing the temporary fixing agent, with the thinned surface being vacuum-sucked as the adsorption surface, an adhesive tape such as a dicing tape is attached to the entire surface of the other surface where the temporary fixing agent remains, and the temporary fixing agent is peeled off together with the tape. Another method is to immerse the wafer in a solvent (for example, aliphatic or aromatic hydrocarbon solvents such as pentane, hexane, heptane, octane, nonane, decane, benzene, toluene, xylene, mesitylene, etc.) to swell and peel off the adhesive layer. Among these methods, the tape peeling method is preferable in terms of the small number of steps and the short required time.

[0133] The wafer after removing the temporary fixing agent can be directly advanced to the next step without cleaning the surface. When cleaning, further, (l) a step of cleaning the support and the wafer from which the temporary fixing agent has been removed, with the circuit formation surface facing up, using a solvent (for example, aliphatic or aromatic hydrocarbon solvents such as pentane, hexane, heptane, octane, nonane, decane, benzene, toluene, xylene, mesitylene, etc.) is preferably performed.

[0134] In step (k), a part of the adhesive (temporary fixing agent) may remain on the circuit formation surface of the wafer from which the temporary fixing agent has been removed. Also, although it is preferable to wash and reuse the peeled support, adhesive residue may also be adhered to the surface of this support. As a method for removing these adhesive residues, methods such as immersion in a solvent (for example, aliphatic or aromatic hydrocarbon solvents such as pentane, hexane, heptane, octane, nonane, decane, benzene, toluene, xylene, mesitylene, etc.) to swell and peel off can be mentioned.

[0135] In a certain embodiment, in obtaining a cured body by curing the above composition, various techniques as described below can be adopted.

[0136] As a first method, it is possible to obtain a single-layer cured body by curing a layer made of a temporary fixing composition containing components (A) to (C).

[0137] And as a second method, a first layer made of a temporary fixing composition containing component (A), component (B), and component (C) and not containing component (D) and a second layer made of a temporary fixing composition containing components (A) to (D) are prepared and cured, respectively, to obtain a cured body having an integrated single layer or multiple layers (multilayers). In this cured body, it is preferable that the concentration distribution of the components is different in the thickness direction, or that the concentration distribution of the components is different between the upper surface and the lower surface in the thickness direction of the cured body. The difference in the concentration distribution of the components can be confirmed by quantifying the UV transmittance for both surfaces of the cured body by the reflectance measurement spectroscopy described above. By this method, an effect of realizing optimal curing can be obtained by combining layers having different light transmittances. Also, in the above-described curing, a black light or a UV-LED can be used as a light source (the same applies to the following methods). As an example of a black light, TUV-8271 manufactured by Toyo Ad-Tech Co., Ltd. (center wavelength 365 nm, illuminance 10 mW / cm 2 ) can be mentioned. Also, as UV-LEDs, a dedicated design mirror unit (wavelength 385 ± 5 nm, illuminance 350 mW / cm 2 , condition: scan pitch 20 mm from the tip of the mirror unit) manufactured by HOYA Corporation, a dedicated design mirror unit (wavelength 395 ± 5 nm, illuminance 375 mW / cm 2 , condition: work distance 20 mm from the tip of the mirror unit) manufactured by HOYA Corporation, a dedicated design mirror unit (wavelength 405 ± 5 nm, illuminance 400 mW / cm 2 , condition: work distance 20 mm from the tip of the mirror unit) manufactured by HOYA Corporation, and the like can be mentioned.

[0138] As a third method, a cured body having a monolayer that is at least partially integrated can be obtained by applying a component (D) (for example, applying by spin coating) onto a cured layer composed of a temporary fixing composition containing a component (A), a component (B), and a component (C). In this case, the concentration distribution of the components is different in the thickness direction of the cured body. The concentration distribution of the components can be quantified by the reflectance measurement spectroscopy for each target layer as described above. By this method, effects such as precisely controlling the UV absorption characteristics can be obtained.

[0139] As a fourth method, a multilayer cured body may be obtained by placing a layer of a commercially available LTHC agent (photo-thermal conversion agent) on a layer composed of a temporary fixing composition containing a component (A), a component (B), and a component (C) and then curing it. By this, an effect that a cured body can be obtained simply can be obtained.

[0140] The cured body obtained by the method as described above can be provided as a structure in combination with an adherend.

[0141] As manufacturing methods of the structure as described above, various examples can also be cited. For example, the first manufacturing method may include a step of applying a first temporary fixing composition containing a component (A), a component (B), and a component (C) and not containing a component (D) on a wafer and partially curing it, a step of applying a second temporary fixing composition containing components (A) to (D) on the partially cured temporary fixing composition, and a step of further placing a transparent substrate on the applied second temporary fixing composition and photo-curing it.

[0142] Also, as a second manufacturing method of the structure, a step of applying a first temporary fixing composition containing a component (A), a component (B), and a component (C) and not containing a component (D) on a wafer and partially curing it as necessary, a step of applying a second temporary fixing composition containing components (A) to (D) on a transparent substrate and partially curing it as necessary, and a step of bringing the surfaces of the wafer and the transparent substrate on which the respective temporary fixing compositions are applied into close contact with each other and then joining them by photo-curing may be included.

[0143] As a third manufacturing method of the structure, there may be one including a step of applying a temporary fixing composition containing components (A), (B), and (C) and not containing component (D) on a wafer and partially curing it as necessary; a step of applying an LTHC layer on a transparent substrate, drying, and curing it; and a step of bonding the surface of the wafer on which the temporary fixing composition is applied and the surface of the transparent substrate on which the LTHC layer is applied and then joining them by photocuring.

[0144] Separate from the above temporary fixing composition, the same composition as that used in the temporary fixing composition of the present invention can also be used as a raw material for a photothermal conversion (LTHC) layer that absorbs IR laser light described in Japanese Patent No. 4565804 and converts it into heat. By adding this composition as a component of the photothermal conversion (LTHC) layer, it becomes possible to improve its heat resistance.

[0145] As another aspect of the present invention, there is provided a method for manufacturing a semiconductor wafer, including a step of applying a temporary fixing adhesive to a semiconductor wafer substrate and / or a support member to bond the semiconductor wafer substrate and the support member; a step of irradiating light having a wavelength of 350 nm to 700 nm (preferably 385 to 700 nm, more preferably 385 to 500 nm, and even more preferably 385 to 450 nm) to cure the temporary fixing adhesive and obtain an adherend; and a step of irradiating the adherend with laser light having a wavelength of less than 385 nm (preferably laser light having a wavelength of 200 nm or more and less than 385 nm) to peel off the semiconductor wafer substrate. This manufacturing method has the advantages that both the curing and peeling steps are processes at room temperature, there is no need to heat or cool the members, generally there is no need to use a solvent, etc., it is simple, and the tact time is short.

[0146] Furthermore, the cured temporary fixing adhesive may form a single layer in the adherend. By doing so, it is preferable for simplifying the process and shortening the tact time.

[0147] In a preferred embodiment, by including both the above-described preferred (C) photo radical polymerization initiator component and (D) UV absorber component in the composition, even if it is a single-layer temporary fixing adhesive, it is possible to achieve both a fast curing rate and a fast peeling rate. Furthermore, when the temporary fixing adhesive is UV-cured, it is possible to significantly reduce the uncured UV-curable monomer component remaining in the cured body, and it is possible to reduce the heat resistance of the cured body and the volatile content under vacuum. That is, for example, it is possible to increase the 2% heating mass loss temperature in the Tg / DTA measurement of the cured body. The temporary fixing adhesive with high heat resistance of the cured body and reduced volatile content under vacuum is extremely useful for recent semiconductor manufacturing processes.

Examples

[0148] The present invention will be described in more detail by the following examples, but the present invention is not limited thereto.

[0149] Unless otherwise specified, the experiments were conducted at 23°C and 50% humidity. Curable resin compositions (hereinafter sometimes referred to as liquid resin compositions) having the compositions (unit: parts by mass) shown in Tables 1a, 1b, and 2 were prepared and evaluated. As each component in the curable resin composition described in the experimental examples, the following compounds were selected.

[0150] (Composition) (A) As a bifunctional (meth)acrylate containing no cyclic skeleton, the following compounds were selected. Hydroxypivalyl hydroxypivalate bis[6-(acryloyloxy)hexanoate] (hereinafter abbreviated as "HPHPAH"; manufactured by Sigma-Aldrich, molecular weight 541) Diacrylate of ε-caprolactone adduct of neopentyl glycol hydroxypivalate (manufactured by Nippon Kayaku Co., Ltd. "KAYARAD HX-220", hereinafter abbreviated as "HX-220", molecular weight 541, carbon number 28) Diacrylate of ε-caprolactone adduct of neopentyl glycol hydroxypivalate (manufactured by Nippon Kayaku Co., Ltd. "KAYARAD HX-620", hereinafter abbreviated as "HX-620", molecular weight 783, carbon number 40) 1,4-Butanediol diacrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., "Biscoat #195", hereinafter abbreviated as "#195", molecular weight 198, carbon number 10)

[0151] (B) As the bifunctional (meth)acrylate having a cyclic skeleton, the following compounds were selected. Ethoxylated bisphenol A diacrylate (2,2-bis(4-acryloxydiethoxyphenyl)propane, solid, molecular weight 424, in formula (1), R 1 , R 2 represents a hydrogen atom, and m and n represent 1. Hereinafter abbreviated as "BPE") Diacrylate having a fluorene skeleton (9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene diacrylate, manufactured by Shin-Nakamura Chemical Co., Ltd., "NK Ester A-BPEF-2", hereinafter abbreviated as "A-BPEF-2", solid, molecular weight 546)

[0152] (C) As the photo radical polymerization initiator, the following compounds were selected. Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide ("Irgacure 819" manufactured by BASF) 1-[9-Ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone 1-(O-acetoxime) ("Irgacure OXE-02" manufactured by BASF, hereinafter abbreviated as "OXE-02")

[0153] (D) As the UV absorber, the following compounds were selected. 2,4-Bis(2-hydroxy-4-butyloxyphenyl)-6-(2,4-bis-butyloxyphenyl)-1,3,5-triazine ("Tinuvin 460" manufactured by BASF, molecular weight 630)

[0154] As the antioxidant, the following compounds were selected. 4-((4,6-Bis(octylthio)-1,3,5-triazin-2-yl)amino)-2,6-di-t-butylphenol ("IRGANOX 565" manufactured by BASF)

[0155] (Preparation of Liquid Sample) The materials were heated and mixed at 80 °C to obtain a homogeneous mixture.

[0156] (Preparation of Cured Sample Using 365 nm UV-LED) The liquid resin composition homogenized by the above heating and mixing was sandwiched between PET films, spread until it reached a thickness of 50 μm (only 0.5 mm for the sample for measuring elastic modulus described later), and cured under the condition of an integrated light quantity of 5000 mJ / cm 2 to produce a cured body. For curing, a UV-LED (center wavelength 365 nm, illuminance 100 mW / cm 2 , HLDL-120U6-NWPSC manufactured by CCS) was used.

[0157] (Preparation of Cured Sample Using 405 nm UV-LED) The liquid resin composition homogenized by the above heating and mixing was sandwiched between PET films, spread until it reached a thickness of 50 μm (only 0.5 mm for the sample for measuring elastic modulus described later), and cured under the condition of an integrated light quantity of 5000 mJ / cm 2 to produce a cured body. For curing, a UV-LED (center wavelength 405 nm, illuminance 100 mW / cm 2 , HLDL-120V0-NWPSC manufactured by CCS) was used.

[0158] Manufacturing process of the test body for evaluating the compatibility of the UV laser peeling process: The prepared liquid resin composition was spin-coated on an 8-inch silicon wafer (diameter 200 mm × thickness 0.725 mm) in an automatic wafer bonder under the condition of a thickness of 50 μm, and then bonded to an 8-inch glass wafer (diameter 201 mm × thickness 0.7 mm) under a reduced pressure condition of 10 Pa in the same apparatus. After bonding, the liquid resin compound was cured using any of the above UV light sources from the glass wafer side to obtain an adhesive body. Next, the silicon wafer surface of the obtained adhesive body was ground and polished to a thickness of 50 μm, and then heat treatment was performed at 300 °C and 20 Pa in a high-temperature and reduced-pressure environment for 1 hour.

[0159] (Evaluation) Compatibility of the materials of the liquid resin composition ("Compatibility of materials", "Absorbance" in Tables 1a, 1b, and 2): The temporarily fixed composition homogenized by the above heating and mixing was cooled to 23°C to check whether the homogeneous state was maintained. Using a UV-visible spectrophotometer V-650 manufactured by JASCO Corporation, the absorbance (OD660) at a wavelength of 660 nm of the sample placed in a cell with a width of 10 mm in the optical path length direction was measured. When the absorbance was less than 0.1, it was considered compatible and acceptable; when the absorbance was 0.1 or more, and when visual phase separation or other non-uniformity was confirmed, it was considered incompatible and unacceptable. In terms of compatibility, an absorbance of less than 0.1 is preferred. For the examples that were determined to be "unacceptable", the subsequent evaluations were omitted. The same applies hereinafter.

[0160] Viscosity ("Spin-coating process compatibility", "Viscosity" in Tables 1a, 1b, and 2): In the above "Compatibility of materials", the viscosity of the liquid resin composition that maintained a homogeneous state at 23°C was measured, and the compatibility with spin coating on the upper surface of the substrate assumed in the actual process was evaluated. Using a rheometer MCR302 manufactured by Anton-Paar, the viscosity was measured at a temperature of 23°C using a cone plate CP50-2. The shear viscosity at a shear rate of 1 s -1 was considered excellent when it was 1000 mPa·s or more and less than 4000 mPa·s, acceptable when it was 4000 mPa·s or more and 10000 mPa·s or less, or 100 mPa·s or more and less than 1000 mPa·s, and unacceptable when it exceeded 10000 mPa·s or was less than 100 mPa·s. In terms of compatibility with the spin-coating process, a viscosity of 100 to 10000 mPa·s is preferred. For the examples that were determined to be "unacceptable", the subsequent evaluations were omitted. The same applies hereinafter.

[0161] 2% Heating mass loss temperature of the cured body under a nitrogen atmosphere ("Heat resistance 1", "2% Heating mass loss temperature of the cured body under a nitrogen atmosphere" in Tables 1a, 1b, and 2): 2 - 10 mg of the obtained cured body was heated from 30°C to 600°C at a heating rate of 10°C / min under a nitrogen stream using a differential thermal - thermogravimetric simultaneous measurement device "TG - DTA STA - 2500" manufactured by Netzsch Japan Co., Ltd., and the heating mass reduction rate of the obtained cured body was measured. The 2% heating mass reduction temperature of the cured body was shown. Those showing a value of 300°C or higher were rated as excellent, those showing a value of 250°C or higher and less than 300°C were rated as good, those showing a value of 200°C or higher and less than 250°C were rated as acceptable, and those showing a value of less than 200°C were rated as unacceptable.

[0162] 2% heating mass reduction temperature under reduced pressure conditions ("Heat resistance 2" in Tables 1a, 1b, 2, "2% heating mass reduction temperature of cured body under reduced pressure"): 2 - 5 mg of the obtained cured body was heated from 30°C to 600°C at a heating rate of 10°C / min under reduced pressure conditions of 30 - 100 Pa using a differential thermal - thermogravimetric simultaneous measurement device "TG - DTA STA - 2500" manufactured by Netzsch Japan Co., Ltd., and the heating mass reduction rate of the obtained cured body was measured. The 2% heating mass reduction temperature of the cured body was shown. Those showing a value of 250°C or higher were rated as excellent, those showing a value of 200°C or higher and less than 250°C were rated as good, those showing a value of 150°C or higher and less than 200°C were rated as acceptable, and those showing a value of less than 150°C were rated as unacceptable. The temperature at which the heating mass reduction rate becomes 2% is preferably 150°C or higher, more preferably 250°C or higher, in terms of compatibility with high - temperature processes in semiconductor manufacturing.

[0163] Pressure change under reduced pressure conditions ("Outgassing property" in Table 4, "Pressure at 300°C"): A Φ4 - inch sheet with a 50 - μm - thick PTFE cut out to Φ3 inches was placed on a 4 - inch silicon wafer, and the liquid resin composition was applied to the cut - out part. It was laminated with a PET sheet and a 4 - inch wafer, and cured under the condition of LED integrated light quantity of 5000 mJ / cm 2 (center wavelength 405 nm, illuminance 100 mW / cm 2 ). The LED was irradiated from the surface of the 4 - inch glass wafer. After curing, the PET film was peeled off, and the laminate of the wafer and the resin composition was cut out into φ1 - cm pieces to obtain test pieces. Using a vacuum - heating gas extraction - mass spectrometer TE - 360S type, 1 - 2×10 -6Under reduced pressure conditions of Pa, the temperature was raised from 50°C to 600°C at a rate of 10°C / min, and the pressure increase due to outgassing was measured. Those that maintained a pressure of less than 5×10 -6 Pa until reaching 300°C were rated excellent, those that maintained a pressure of 5×10 -6 or more and less than 1×10 -5 Pa were rated good, those that maintained a pressure of 1×10 -5 or more and less than 5×10 -4 Pa were rated acceptable, and those that reached 5×10 -4 Pa or more were rated unacceptable. In terms of compatibility with high-temperature processes in semiconductor manufacturing, less than 5×10 -4 Pa is preferred, and less than 5×10 -6 Pa is more preferred.

[0164] Adhesion at high temperature (the "adhesion under high-temperature conditions (300°C·1h·reduced pressure 20 Pa)", "width of discoloration at the outer edge", "peeling due to heating" in Tables 1a, 1b, and 2): Using the prepared liquid resin composition, a 4-inch silicon wafer (diameter 10 cm × thickness 0.47 mm) and a 4-inch glass wafer (diameter 10 cm × thickness 0.7 mm) were bonded together. When bonding, the thickness of the resin composition was adjusted by adding 0.1% by mass of silica particles (product name: High Preshica TS N3N, average particle size 50 μm) manufactured by Ube Eximer Co., Ltd. to the temporary fixing agent and using the mixed product. After bonding, the LED integrated light quantity was 5000 mJ / cm 2 (center wavelength 405 nm, illuminance 100 mW / cm 2It was cured under the conditions of ), and a test piece for evaluating adhesiveness under high-temperature and reduced-pressure conditions was produced. The adhesive was applied to the entire bonding surface. The LED was irradiated from the surface of the 4-inch glass wafer. The completed test piece was placed on the hot plate in the vacuum hot plate chamber manufactured by MSA Factory Co., Ltd. with the 4-inch silicon wafer side facing down and heated, and the width of the discolored area at the outer edge toward the center of the wafer and the presence or absence of peeling visually confirmed from the glass side were observed. Under a reduced pressure of 20 Pa, the temperature of the hot plate was 300 °C and the heating duration was 1 hour. In the "Adhesiveness under high-temperature conditions (300 °C·1 h·reduced pressure 20 Pa)" in Tables 1a, 1b, and 2, those without peeling or discoloration were rated excellent, those with a width of the spread from the outer edge of the peeling or discolored area toward the center of 5 mm or less were rated good, those with a width greater than 5 mm and 10 mm or less were rated acceptable, and those with peeling or discoloration greater than that were rated unacceptable.

[0165] (1) UV laser lift-off process compatibility (the "UV laser lift-off property", "minimum value of the time required to achieve complete lift-off", in Tables 1a, 1b, 2, and the "UV laser irradiation conditions" in Table 3): The obtained 8-inch test body was irradiated with a UV laser over a square area of 210 mm on each side fixed around the test body so as to scan the entire surface of the test body from the glass support side. Each condition shown in Table 3 was sequentially applied to each of the examples in Tables 1a and 1b as the UV laser irradiation conditions for evaluation. The UV laser used was QLA-355 manufactured by Quark Technology Co., Ltd., with an output of 9.3 W, a pulse energy of 235 μJ, an energy density of 11968 mJ / cm 2 , a frequency of 40 kHz, a beam diameter (spot diameter) of 50 μm, a scan pitch of 500 μm, and a scan speed of 20 m / s, which were the conditions shown in condition number 9 in Table 3 (Table 3 describes the trials for examining this optimal condition). The lift-off property after irradiation was defined as complete lift-off when the adhesive force was completely lost and the glass support slid (or moved) freely on the silicon wafer (adhesive force = 0), and the UV laser lift-off process compatibility was evaluated by the minimum value of the time required for the UV laser irradiation process to obtain this state of complete lift-off. Those with a minimum value of the required time of less than 15 seconds were rated excellent, those with a time of 15 seconds or more and less than 30 seconds were rated good, those with a time of 30 seconds or more and less than 60 seconds were rated acceptable, and those with a time of 60 seconds or more were rated unacceptable.

[0166]

Table 1a

[0167]

Table 1b

[0168]

Table 2

[0169]

Table 3

[0170]

Table 4

[0171] From the results of the examples in Table 1a, 1b and Table 4 and the comparative examples in Table 2, it can be seen that the resin composition of the present invention is a composition excellent in compatibility, spin-coating process suitability and heat resistance. That is, when the component (B) is not used as in Comparative Example 1, the spin-coating process suitability cannot be obtained. Also, when the component (A) is not used as in Comparative Examples 2 and 3, it becomes solid and is still unsuitable for the spin-coating process.

[0172] Also, from the results of Table 4, it can be seen that the composition of the present invention is extremely excellent in outgassing property.

[0173] The resin composition of the present invention ensures the compatibility of materials and the minimum viscosity required for spin-coating, and is excellent in adhesiveness, heat resistance and peelability under room temperature and high temperature conditions.

[0174] The resin composition according to this example has compatibility with the UV laser peeling process and compatibility with the mechanical peeling process. After inserting a thin and sharp metal blade for crack generation into the substrate interface at the end of the silicon wafer / glass support laminate produced by the method described in the above example, the glass support is fixed horizontally with the upper side facing up, and an upward stress is applied to the upper support after blade insertion to advance the crack and peel the wafer and support. The peeling was possible by this method.

[0175] Also, as a method for evaluating the energy required for peeling, a method called the Maszara test was used, in which a thin and sharp blade was inserted by a certain distance as described above, and the distance by which the crack advanced at that time was measured. Also in this test, the sample bonded using the liquid resin having the composition of Example 1 showed a sufficiently low value.

[0176] The resin composition according to this example has compatibility with the UV laser peeling process. Regarding the silicon wafer / glass support laminate produced by the method described in the above example, the silicon wafer was fixed to a fixing device with the lower side facing down, and after irradiating with a UV laser QLA-355 manufactured by Quark Technology Co., Ltd. from the glass support side at an output of 9.3 W, a frequency of 40 kHz, a scan pitch of 200 μm, and a beam diameter of 50 μm, when the peeling force was measured in the same procedure as the above (3) mechanical peeling process compatibility evaluation, the value of the peeling force before UV irradiation, which was 3 N, decreased to 0 N.

Industrial Applicability

[0177] The composition that can be provided by the present invention is excellent in heat resistance, low outgassing property, and peelability.

[0178] The composition of the present invention is excellent in workability and productivity because it can easily exhibit strong adhesiveness simply by irradiating ultraviolet rays or visible light in the manufacture of various electronic components, optical components, and optical devices. The cured product of the composition of the present invention has an extremely small amount of outgas even at a high temperature of 250°C. The composition of the present invention is easy to peel off after processing. Therefore, various electronic components, optical components, and optical devices adhered using the composition of the present invention are applicable even when vapor deposition treatment at a high temperature exceeding 200°C or baking painting at a high temperature is performed.

[0179] In addition to electronic components such as ICs, resistors, and inductors, optical components such as image sensors are also applied to surface mounting on circuit boards. In that case, they are passed through high-temperature solder reflow. In recent years, especially with the lead-freeization of solder, the temperature conditions of solder reflow have become stricter. In such production processes, in order to improve the quality of optical components and optical devices, or to improve productivity and production yield, the places where the composition of the present invention is used are required to be able to sufficiently withstand high-temperature heat treatment. The optical components and optical devices manufactured using the composition of the present invention can sufficiently withstand the high-temperature heat treatment, so they are very useful industrially.

Claims

1. A temporary fixing composition containing the following (A) to (C). (A) A bifunctional (meth)acrylate having (meth)acryloyl groups at both ends and not containing a cyclic skeleton (B) A bifunctional (meth)acrylate having a fluorene skeleton (C) A photoinitiator for radical polymerization

2. The temporary fixing composition according to Claim 1, further containing the following (D). (D) A UV absorber that, when dissolved at a concentration of 0.002% by mass in a solvent having no maximum absorption at a wavelength of 290 to 410 nm, has a transmittance of 50% or less at a wavelength of 355 nm with an optical path length of 1 cm and a transmittance higher than 50% at a wavelength of 385 to 420 nm

3. The temporary fixing composition according to Claim 1 or 2, wherein the component (A) has a molecular weight of 250 or more.

4. The temporary fixing composition according to Claim 1 or 2, wherein the component (A) is a bifunctional (meth)acrylate having no alkyl ether skeleton.

5. The temporary fixing composition according to Claim 1 or 2, wherein the component (A) is a bifunctional (meth)acrylate having an aliphatic hydrocarbon skeleton or an aliphatic hydrocarbon skeleton having a hydroxy group and / or an ester skeleton.

6. The temporary fixing composition according to Claim 1 or 2, wherein the component (A) is a diacrylate of an ε-caprolactone adduct of hydroxypivalic acid neopentyl glycol.

7. The temporary fixing composition according to Claim 1 or 2, wherein the component (B) is liquid having a viscosity of 500 mPa·s or more at 23°C or is solid at 23°C.

8. The temporary fixing composition according to Claim 1 or 2, wherein the component (B) contains 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene di(meth)acrylate.

9. The temporary fixing composition according to Claim 1 or 2, wherein the component (C) is a photoinitiator for radical polymerization that generates radicals with light having a wavelength of 350 nm or more.

10. The component (C) is bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(η 5 -2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-ylphenyl)-butan-1-one, 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-O-benzoyloxime, and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]ethanone 1-(O-acetoxyoxime), and is one or more selected from the group consisting of the provisional fixing composition according to claim 1 or 2.

11. The temporary fixing composition according to Claim 1 or 2, containing 0.01 to 5 parts by mass of the component (C) with respect to 100 parts by mass in total of the components (A) to (B).

12. The temporary fixing composition according to Claim 1 or 2, wherein the mass ratio of the component (A) to the component (B) is in the range of 5 to 95:5 to 95 with respect to 100 parts by mass in total of the component (A) and the component (B).

13. The temporary fixing composition according to Claim 1 or 2, further containing the following (E). (E) A monofunctional (meth)acrylate

14. The temporary fixing composition according to claim 13, containing 0 to 50 parts by mass of component (E) with respect to a total of 100 parts by mass of components (A) to (B).

15. The temporary fixing composition according to claim 1 or 2, which does not contain (meth)acrylate other than components (A) and (B).

16. The temporary fixing composition according to claim 1 or 2, further containing the following (F). (F)Polymer

17. The temporary fixing composition according to claim 16, containing 0 to 50 parts by mass of component (F) with respect to a total of 100 parts by mass of components (A) to (B).

18. The temporary fixing composition according to claim 1 or 2, characterized in that the viscosity at 23 °C of the temporary fixing composition is in the range of 100 to 10,000 mPa·s.

19. A temporary fixing adhesive containing the temporary fixing composition according to claim 1 or 2.

20. An adherend obtained by adhering a substrate using the temporary fixing adhesive according to claim 19.

21. A cured body obtained by curing the temporary fixing composition according to claim 1.

22. The cured body according to claim 21, which is a single-layer cured body.

23. The cured body according to claim 21 or 22, having a 2% mass loss temperature of 250 °C or higher under a nitrogen atmosphere.

24. The cured body according to claim 21 or 22, having a 2% mass loss temperature of 250 °C or higher under a reduced pressure environment of 30 to 100 Pa.

25. The following (A) to (C): (A)A bifunctional (meth)acrylate having (meth)acryloyl groups at both ends and not containing a cyclic skeleton (B)A bifunctional (meth)acrylate having a fluorene skeleton (C)A photo radical polymerization initiator An adherend obtained by adhering a substrate using a temporary fixing adhesive containing the above, wherein the temporary fixing adhesive is cured by light with a wavelength of 350 nm or more, and the substrate is peeled off by laser light with a wavelength of less than 385 nm.

26. A step of applying the temporary fixing adhesive according to claim 19 to a semiconductor wafer substrate and / or a support member to adhere the semiconductor wafer substrate and the support member; A step of curing the temporary fixing adhesive by irradiating light with a wavelength of 350 nm to 700 nm from one or more light sources selected from the group consisting of a black light, a UV-LED, and a visible light-LED to obtain an adherend; A step of irradiating the adherend with laser light having a wavelength of less than 385 nm to peel off the semiconductor wafer substrate A method for manufacturing a semiconductor wafer, including the above steps.

27. The manufacturing method according to claim 26, wherein the cured temporary fixing adhesive forms a single layer in the adhesive body.

28. The temporary fixing adhesive according to claim 19, wherein the use is for UV laser peeling.

29. A first cured layer comprising a temporary fixing composition containing a bifunctional (meth)acrylate having (meth)acryloyl groups at both ends and not containing a cyclic skeleton as component (A), a bifunctional (meth)acrylate having a fluorene skeleton as component (B), and a photo radical polymerization initiator as component (C), and not containing a UV absorber having a transmittance of 50% or less at a wavelength of 355 nm at an optical path length of 1 cm and a transmittance higher than 50% at wavelengths of 385 to 420 nm when dissolved in a solvent having no maximum absorption at wavelengths of 290 to 410 nm at a concentration of 0.002% by mass, and a second cured layer comprising the temporary fixing composition according to claim 2, and a cured body having different concentration distributions of components in the thickness direction.

30. A first cured layer obtained by curing the temporary fixing composition according to claim 1 containing component (A), component (B), and component (C), and a second cured layer obtained by applying a UV absorber on the first cured layer, and a cured body having different concentration distributions of components in the thickness direction.

31. A cured body having a first cured layer obtained by curing the temporary fixing composition according to claim 1 containing component (A), component (B), and component (C), and a photothermal conversion (LTHC) cured layer.

32. The cured body according to any one of claims 29 to 31, satisfying all of the following conditions. - Among the light transmittances of the cured body having a thickness of 50 μm, the light transmittance in the wavelength region of 395 nm or more within the wavelengths of the light source used for curing is 70% or more. - Among the light transmittances of the cured body having a thickness of 50 μm, the light transmittance in the wavelength region of 350 nm or more and less than 395 nm within the wavelengths of the light source used for curing is 20% or more. - Among the light transmittances of the cured body having a thickness of 50 μm, the light transmittance at the wavelength (355 nm) of the UV laser used for UV laser peeling is 1% or less.

33. A structure including the cured body according to any one of claims 29 to 31 and an adherend.

34. Applying a temporary fixing composition on a wafer, the composition containing, as component (A), a bifunctional (meth)acrylate having (meth)acryloyl groups at both ends and not containing a cyclic skeleton, as component (B), a bifunctional (meth)acrylate having a fluorene skeleton, and as component (C), a photo radical polymerization initiator, and not containing a UV absorber which, when dissolved in a solvent having no maximum absorption at wavelengths of 290 to 410 nm at a concentration of 0.002% by mass, has a transmittance of 50% or less at a wavelength of 355 nm with an optical path length of 1 cm and a transmittance higher than 50% at wavelengths of 385 to 420 nm, and partially curing the composition; Applying the temporary fixing composition according to claim 2 on the partially cured temporary fixing composition; Further placing a transparent substrate on the applied temporary fixing composition and photo-curing it; A method for manufacturing a structure, comprising the above steps.

35. Applying a temporary fixing composition on a wafer, the composition containing, as component (A), a bifunctional (meth)acrylate having (meth)acryloyl groups at both ends and not containing a cyclic skeleton, as component (B), a bifunctional (meth)acrylate having a fluorene skeleton, and as component (C), a photo radical polymerization initiator, and not containing a UV absorber which, when dissolved in a solvent having no maximum absorption at wavelengths of 290 to 410 nm at a concentration of 0.002% by mass, has a transmittance of 50% or less at a wavelength of 355 nm with an optical path length of 1 cm and a transmittance higher than 50% at wavelengths of 385 to 420 nm, and partially curing the composition as necessary; Applying the temporary fixing composition according to claim 2 on a transparent substrate and partially curing the composition as necessary; Bringing the surfaces of the wafer and the transparent substrate on which the temporary fixing composition is applied into close contact with each other, and then joining them by photo-curing; A method for manufacturing a structure, comprising the above steps.

36. Applying the temporary fixing composition according to claim 1, which contains component (A), component (B), and component (C) and does not contain component (D), on a wafer, and partially curing the composition as necessary; Applying a light-to-heat conversion (LTHC) layer on a transparent substrate, drying, and curing it; Bringing the surface of the wafer on which the temporary fixing composition is applied into close contact with the surface of the transparent substrate on which the LTHC layer is applied, and then joining them by photo-curing; A method for manufacturing a structure, comprising the above steps.

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