Adhesive composition and film sheet

Abstract

The present invention provides an adhesive composition and a film sheet that can be preferably used as a UV peel adhesive for semiconductor processing and have excellent heat resistance along with antistatic performance. The adhesive composition constituting the adhesive layer comprises: (A) an alkyl (meth)acrylate having C1 to C18 carbon atoms in the alkyl group; (B) a copolymerizable nitrogen-containing vinyl monomer that does not contain a carboxyl group; and (C) a copolymerizable monomer containing a hydroxyl group, comprising a (meth)acrylic polymer with a weight average molecular weight of 1 million to 3.5 million; (D) an acrylate having 4 or more unsaturated double bonds in the molecule as a tetrafunctional or more unsaturated double bond compound; (E) an aromatic isocyanate compound having 3 or more functions as a crosslinking agent; (F) a silane coupling agent; (G) an ionic compound with a melting point of 25°C or higher as an antistatic agent; and (H) a photoinitiator.

Description

Technology Field

[0001] The present invention relates to an adhesive composition and a film sheet. Background Technology

[0002] As adhesives used for semiconductor processing tapes, so-called UV release adhesives are generally known, such as adhesives for dicing tapes (see, for example, Patent Document 1). UV release adhesives have a reduced adhesive strength of 1N or less after UV irradiation, making them easy to peel off. Prior art literature

[0003] Japanese Patent Publication No. 6713864 The problem to be solved

[0004] Recent semiconductor processes are becoming more complex, and the requirements for semiconductor processing tapes are becoming stricter year after year. In particular, for semiconductor processing tapes used in processes where ICs are mounted directly on the wafer, such as Fan-Out Wafer Level Packaging (FO-WLP), heat resistance for reflow processes is also required. Furthermore, considering potential damage to electronic components such as ICs, antistatic functionality is sometimes required when the process tape is peeled off.

[0005] The present invention has been made in consideration of the above circumstances and aims to provide an adhesive composition and a film sheet that can be preferably used as a UV peel adhesive for semiconductor processing and have excellent heat resistance along with antistatic performance. means of solving the problem

[0006] A first embodiment is an adhesive composition comprising a (meth)acrylic polymer, a tetrafunctional or more unsaturated double bond compound, a crosslinking agent, (F) a silane coupling agent, (G) an antistatic agent, and (H) a photoinitiator, wherein the (meth)acrylic polymer is a copolymer having a weight average molecular weight of 1 million to 3.5 million, comprising (A) one or more alkyl (meth)acrylates having C1 to C18 carbon atoms in the alkyl group, a copolymerizable monomer not containing a carboxyl group, (B) one or more copolymerizable nitrogen-containing vinyl monomers, and (C) one or more copolymerizable monomers containing a hydroxyl group, and the unsaturated double bond compound is (D) one or more selected from acrylates having four or more unsaturated double bonds within the molecule, and the adhesive composition is such that the (A) alkyl group has C1 to C18 carbon atoms Based on 100 parts by weight of the total of the alkyl (meth)acrylate and the copolymerizable nitrogen-containing vinyl monomer (B), the above-mentioned crosslinking agent comprises 0.1 to 10 parts by weight of (E) an aromatic isocyanate compound with three or more functions, 0.1 to 3 parts by weight of (F) a silane coupling agent, 0.5 to 30 parts by weight of one or more ionic compounds with a melting point of 25°C or higher as (G) an antistatic agent, and 0.1 to 5.0 parts by weight of (H) a photoinitiator.

[0007] The second embodiment is an adhesive film formed by laminating a 20 μm thick adhesive layer formed by heat drying treatment from the adhesive composition of the first embodiment onto a 27 μm thick PEEK substrate, wherein the 90° peel adhesion strength to a PBO-treated silicon wafer is 1 N / 25 mm or more, and subsequently, the adhesion strength after a test performed by UV irradiating a silicon wafer with a diameter of 30.48 cm (12 inches) with a metal halide lamp or a 365 nm wavelength LED-UV lamp at a rate of 3000 mJ, followed by heating at 240°C for 5 minutes, and additionally heating at 165°C for 2.5 hours is 0.5 N / 25 mm or less, and the surface resistivity of the surface of the adhesive layer after peeling from the silicon wafer is 1.0 × 10⁻⁶+10 The Ω / □ is less than or equal to the 90° peel adhesive strength of the adhesive film on BA-treated stainless steel when tested in the same way as the silicon wafer is 0.5 N / 25 mm or more, and the surface of the silicon wafer after peeling is not contaminated.

[0008] The third embodiment is the first or second embodiment, wherein the (meth)acrylic polymer comprises 70 to 95 parts by weight of at least one type of (A) alkyl (meth)acrylate having a carbon number of C1 to C18 alkyl groups, comprising at least 40 parts by weight of n-butyl acrylate, and 100 parts by weight of (B) copolymerizable nitrogen-containing vinyl monomer, comprising at least 5 to 30 parts by weight of one type of nitrogen-containing vinyl monomer not containing hydroxyl groups, and (C) one or more copolymerizable monomers containing hydroxyl groups.

[0009] The fourth embodiment is an embodiment of any one of the first to third embodiments, wherein the (meth)acrylic polymer comprises, with respect to 100 parts by weight of the total of (A) an alkyl (meth)acrylate having C1 to C18 carbon atoms of an alkyl group and (B) a copolymerizable nitrogen-containing vinyl monomer, one or more selected from hydroxyl group-containing (meth)acrylate and hydroxyl group-containing (meth)acrylamide as (C) a copolymerizable monomer containing a hydroxyl group, in a ratio of 0.1 to 5 parts by weight.

[0010] The fifth embodiment is, in any one of the first to fourth embodiments, wherein the ionic compound having a melting point of 25°C or higher as (G) the antistatic agent comprises: (G-1) an ammonium-based ionic compound having a fluorogroup-containing anion, wherein the fluorogroup-containing anion is one selected from the group consisting of pentafluorobenzenesulfonate, hexafluorophosphate, bis(trifluoromethanesulfonyl)imide, bis(fluorosulfonyl)imide, and trilate; (G-2) an ionic compound comprising a borate anion having a pentafluorophenyl group (C6F5 group) and a cation, wherein the cation is one selected from the group consisting of pyridinium, imidazolium, sulfonium, phosphonium, pyrrolidinium, guanidinium, ammonium, isouronium, thiouronium, piperidinium, pyrazolium, methylium, lithium, and morpholium; and (G-3) The compound is an ionic compound composed of a nonafluorobutanesulfonate anion and a cation, and contains 0.5 to 30 parts by weight of one or more selected from the group of ionic compounds in which the cation is selected from the group consisting of pyridinium, imidazolium, phosphonium, sulfonium, pyrrolidinium, guanidinium, ammonium, isouronium, thiouronium, piperidinium, pyrazolium, methylium, lithium, and morpholium.

[0011] The sixth embodiment is one or more selected from the group of compounds consisting of 8-hydroxyoctyl(meth)acrylate, 6-hydroxyhexyl(meth)acrylate, 4-hydroxybutyl(meth)acrylate, 2-hydroxyethyl(meth)acrylate, N-hydroxy(meth)acrylamide, N-hydroxymethyl(meth)acrylamide, and N-hydroxyethyl(meth)acrylamide, in any one of the first to fifth embodiments.

[0012] The seventh embodiment is an embodiment of any one of the first to sixth, wherein the adhesive composition comprises 5 to 30 parts by weight of one or more acrylate compounds selected from the group consisting of pentaerythritol tetraacrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol polyacrylate, and polypentaerythritol polyacrylate, based on a total of 100 parts by weight of (A) an alkyl (meth)acrylate having C1 to C18 carbon atoms in an alkyl group and (B) a copolymerizable nitrogen-containing vinyl monomer, wherein (D) an acrylate having four or more unsaturated double bonds in its molecule.

[0013] The eighth embodiment is one or more of the (E) aromatic isocyanate compounds having three or more functions in any one of the first to seventh embodiments, selected from the adducts of tolylene diisocyanate and xylylene diisocyanate.

[0014] The ninth embodiment is an embodiment of any one of the first to eighth, wherein the (F) silane coupling agent has, as an organic functional group, one or more selected from the group consisting of an epoxy group, a (meth)acryloxy group, a mercapto group, an amino group, and a polyether group.

[0015] The 10th embodiment is a film sheet having an adhesive layer formed from an adhesive composition of any one of the 1st to 9th embodiments.

[0016] The 11th embodiment is the 10th embodiment in which the substrate of the adhesive layer is a heat-resistant substrate with a thickness of 25 μm or more.

[0017] In the 12th embodiment, the heat-resistant substrate is selected from a polyimide-based film, PEEK, PEN, a polyamide-based film, and a polystyrene-based film in the 11th embodiment.

[0018] The 13th embodiment is used in a semiconductor processing process in any one of the 10th to 12th embodiments.

[0019] The 14th embodiment is used in the wafer-level packaging process as the semiconductor processing process in the 13th embodiment. Effects of the invention

[0020] According to the present invention, an adhesive composition and a film sheet that can be preferably used as a UV peel adhesive for semiconductor processing and have excellent heat resistance along with antistatic performance can be provided.

[0021] The adhesive composition of the present invention can be used as an adhesive that maintains heat resistance while maintaining the performance of conventional UV release adhesives, and enables easy peeling even after processes requiring heat resistance. Conventional UV release adhesives could not accommodate new manufacturing processes because their adhesive strength increased significantly during the heating process following UV irradiation; however, the present invention makes it possible to combine UV release performance and heat resistance performance by using an adhesive composition containing a (meth)acrylic polymer of a specific composition and other compounds. Brief explanation of the drawing

[0022] FIG. 1 is a cross-sectional view showing an example of a film sheet being laminated to a substrate. Specific details for implementing the invention

[0023] The present invention will be described below based on preferred embodiments.

[0024] The adhesive composition of the embodiment is an adhesive composition containing (meth)acrylic polymer, a tetrafunctional or more unsaturated double bond compound, a crosslinking agent, (F) a silane coupling agent, (G) an antistatic agent, and (H) a photoinitiator, wherein the (meth)acrylic polymer comprises (A) one or more alkyl (meth)acrylates having C1 to C18 carbon atoms in the alkyl group, a copolymerizable monomer that does not contain a carboxyl group, (B) one or more copolymerizable nitrogen-containing vinyl monomers, and (C) one or more copolymerizable monomers containing a hydroxyl group.

[0025] The above (meth)acrylic polymer may be a copolymer of (A) one or more alkyl (meth)acrylates having C1 to C18 carbon atoms in the alkyl group, (B) one or more copolymerizable nitrogen-containing vinyl monomers, and (C) one or more copolymerizable monomers containing hydroxyl groups, and may additionally be a copolymer containing monomers other than these. It is preferable to copolymerize only copolymerizable monomers that do not contain carboxyl groups to form the (meth)acrylic polymer.

[0026] (A) an alkyl (meth)acrylate having C1 to C18 carbon atoms in the alkyl group and (B) a copolymerizable nitrogen-containing vinyl monomer are monomers that do not contain hydroxyl groups and carboxyl groups. In the following description, the ratio of the total of these may be referred to as “100 parts by weight of the total of (A) and (B).”

[0027] (A) The alkyl (meth)acrylate having C1 to C18 carbon atoms in the alkyl group is not particularly limited and can be appropriately selected. Examples of alkyl groups of the alkyl (meth)acrylate monomer include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl, t-butyl, pentyl, hexyl, heptyl, n-octyl, isooctyl, 2-ethylhexyl, n-nonyl, isononyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, myristyl, stearyl, isomyristyl, isostearyl, cyclopentyl, cyclohexyl, etc.

[0028] In this specification, the (meth)acrylate may be either an acrylate or a methacrylate. For example, if the alkyl group is n-butyl, the n-butyl (meth)acrylate may be either an n-butyl acrylate or a n-butyl methacrylate. The alkyl group of the alkyl (meth)acrylate monomer may be either acyclic (straight-chain, branched) or cyclic.

[0029] The alkyl (meth)acrylate having a carbon number of C1 to C18 of the alkyl group (A) copolymerized with the above (meth)acrylic polymer may be one type or two or more types. It is preferable that the above (meth)acrylic polymer contains, in a ratio of 70 to 95 parts by weight, the total of one or more alkyl (meth)acrylates having a carbon number of C1 to C18 of the alkyl group (A) in 100 parts by weight of the total of (A) and (B).

[0030] It is preferable that the above (meth)acrylic polymer contains at least 40 parts by weight of n-butyl acrylate among 100 parts by weight of the total of (A) and (B). The proportion of n-butyl acrylate may be 50 parts by weight, 60 parts by weight, 70 parts by weight, 80 parts by weight, 90 parts by weight, 95 parts by weight, etc. In the above (meth)acrylic polymer, (A) the alkyl (meth)acrylate having C1 to C18 carbon atoms in the alkyl group may be n-butyl acrylate alone, or n-butyl acrylate may be used in combination with other alkyl (meth)acrylates.

[0031] In the above (meth)acrylic polymer, (B) the copolymerizable nitrogen-containing vinyl monomer is a copolymerizable monomer that does not contain a carboxyl group, and is also a monomer different from (C) the copolymerizable monomer that contains a hydroxyl group. Preferably, (B) the copolymerizable nitrogen-containing vinyl monomer is a monofunctional unsaturated double-bond compound.

[0032] (B) Copolymerizable nitrogen-containing vinyl monomers are not particularly limited, but may include N-vinyl substituted lactams, N-vinyl substituted cyclic amines, N-(meth)acryloyl substituted cyclic amines, acrylic monomers containing N,N-dialkyl substituted amino groups, acrylic monomers containing N,N-dialkyl substituted amide groups, etc. In this specification, (meth)acryloyl may be either acryloyl and / or methacryloyl.

[0033] Examples of N-vinyl substituted lactams include N-vinylpyrrolidone, methylvinylpyrrolidone, and N-vinylcaprolactam.

[0034] Examples of N-vinyl substituted cyclic amines include N-vinylpyridine, N-vinylpiperidone, N-vinylpyrimidine, N-vinylpiperazine, N-vinylpyrazine, N-vinylpyrrole, N-vinylimidazole, N-vinyloxazole, N-vinylmorpholine, etc.

[0035] Examples of N-(meth)acryloyl-substituted cyclic amines include N-(meth)acryloylmorpholine, N-(meth)acryloylpiperazine, N-(meth)acryloylaziridine, N-(meth)acryloylpyrrolidine, N-(meth)acryloylpiperidine, etc.

[0036] Examples of acrylic monomers containing an N,N-dialkyl substituted amino group include dialkylamino substituted alkyl (meth)acrylates and dialkylamino substituted alkyl (meth)acrylamides. Examples of acrylic monomers containing an N,N-dialkyl substituted amide group include N,N-dialkyl substituted (meth)acrylamides. In this specification, (meth)acrylamide may be either acrylamide and / or methacrylamide.

[0037] Examples of dialkylamino-substituted alkyl (meth)acrylates include N-ethyl-N-methylaminoethyl (meth)acrylate, N-methyl-N-propylaminoethyl (meth)acrylate, N-methyl-N-isopropylaminoethyl (meth)acrylate, N,N-dimethylaminomethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, N,N-dimethylaminobutyl (meth)acrylate, N,N-dipropylaminoethyl (meth)acrylate, N,N-dibutylaminoethyl (meth)acrylate, etc.

[0038] Examples of dialkylamino-substituted alkyl (meth)acrylamides include N-ethyl-N-methylaminopropyl (meth)acrylamide, N-methyl-N-propylaminopropyl (meth)acrylamide, N-methyl-N-isopropylaminopropyl (meth)acrylamide, N,N-dimethylaminopropyl (meth)acrylamide, N,N-diethylaminopropyl (meth)acrylamide, N,N-dipropylaminopropyl (meth)acrylamide, N,N-dimethylaminoethyl (meth)acrylamide, N,N-diethylaminoethyl (meth)acrylamide, etc. The dialkylamino-substituted alkyl group may also serve as the N-substituent of the (meth)acrylamide compound.

[0039] Examples of N,N-dialkyl-substituted (meth)acrylamides include N-ethyl-N-methyl(meth)acrylamide, N-methyl-N-propyl(meth)acrylamide, N-methyl-N-isopropyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N,N-dipropyl(meth)acrylamide, N,N-diisopropyl(meth)acrylamide, N,N-dibutyl(meth)acrylamide, etc.

[0040] The copolymerizable nitrogen-containing vinyl monomer (B) copolymerized to the above (meth)acrylic polymer may be one type or two or more types. It is preferable that the above (meth)acrylic polymer contains a total of one or more copolymerizable nitrogen-containing vinyl monomers (B) in a ratio of 5 to 30 parts by weight to the total of 100 parts by weight of (A) and (B).

[0041] In the above (meth)acrylic polymer, (C) copolymerizing monomers containing hydroxyl groups may include hydroxyl group-containing (meth)acrylates, hydroxyl group-containing (meth)acrylamides, etc. (C) copolymerizing monomers containing hydroxyl groups are monomers that do not contain carboxyl groups. (C) copolymerizing monomers containing hydroxyl groups are preferably monofunctional unsaturated double-bond compounds.

[0042] Examples of hydroxyl group-containing (meth)acrylates include 2-hydroxyethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, etc.

[0043] Examples of hydroxyl group-containing (meth)acrylamides include N-hydroxy(meth)acrylamide, N-hydroxymethyl(meth)acrylamide, N-hydroxyethyl(meth)acrylamide, etc.

[0044] (C) It is preferable that the copolymer monomer containing a hydroxyl group is one or more selected from the group of compounds consisting of 8-hydroxyoctyl(meth)acrylate, 6-hydroxyhexyl(meth)acrylate, 4-hydroxybutyl(meth)acrylate, 2-hydroxyethyl(meth)acrylate, N-hydroxy(meth)acrylamide, N-hydroxymethyl(meth)acrylamide, and N-hydroxyethyl(meth)acrylamide.

[0045] The copolymerizing monomers containing (C) hydroxyl groups that are copolymerized with the above (meth)acrylic polymer may be one type or two or more types. It is preferable that the above (meth)acrylic polymer contains a total of one or more copolymerizing monomers containing (C) hydroxyl groups in a ratio of 0.1 to 5 parts by weight to 100 parts by weight of the total of (A) and (B).

[0046] (C) Cosynthetic monomers containing hydroxyl groups can react with isocyanate compounds, which are crosslinking agents, just like monomers containing carboxyl groups. For this reason, by using (C) copolymersynthetic monomers containing hydroxyl groups instead of monomers containing carboxyl groups, it may be helpful to improve the adhesive strength of the adhesive layer and also reduce corrosiveness. The acid value of the (meth)acrylic polymer may be 0.1 or less.

[0047] The polymerization method of the copolymer used as the above (meth)acrylic polymer is not particularly limited, and appropriately known polymerization methods such as solution polymerization and emulsion polymerization can be used. It is preferable that the above (meth)acrylic polymer contains 50 to 100 weight percent of an acrylic monomer, such as a (meth)acrylate monomer or a (meth)acrylamide monomer.

[0048] The weight average molecular weight of the above (meth)acrylic polymer is preferably 1 million to 3.5 million, and may be 1.5 million or more.

[0049] The adhesive composition of the embodiment contains, together with the (meth)acrylic polymer, an unsaturated double bond compound having four or more functional groups. The unsaturated double bond included in the unsaturated double bond compound is preferably an unsaturated double bond between carbons that does not constitute an aromatic group. The unsaturated double bond may be included in a (meth)acryloyl group such as (meth)acrylate or (meth)acrylamide, or may be a vinyl group, an allyl group, etc.

[0050] The above unsaturated double bond compound is preferably one or more selected from (D) acrylates having four or more unsaturated double bonds in the molecule. Examples of acrylates having four or more unsaturated double bonds in the molecule include acrylate compounds derived from polyol compounds having four or more hydroxyl groups in the molecule.

[0051] Examples of the above polyol compounds include pentaerythritol, dipentaerythritol, polypentaerythritol, ditrimethylolpropane, polytrimethylolpropane, etc. (D) An acrylate having four or more unsaturated double bonds in a molecule corresponds to a compound in which all or part of the hydroxyl groups included in the above polyol compound are acrylates with four or more.

[0052] The above adhesive composition preferably contains 1 to 50 parts by weight of an acrylate having four or more unsaturated double bonds in the molecule of (D), and more preferably 5 to 30 parts by weight, based on 100 parts by weight of the total of (A) and (B). Additionally, as an acrylate having four or more unsaturated double bonds in the molecule of (D), it is preferable to contain 5 to 30 parts by weight of one or more acrylate compounds selected from the group consisting of pentaerythritol tetraacrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol polyacrylate, and polypentaerythritol polyacrylate.

[0053] The above adhesive composition preferably contains (E) an aromatic isocyanate compound with three or more functional groups as a crosslinking agent. Examples of aromatic isocyanate compounds include compounds derived from tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), diphenylmethane diisocyanate (MDI), etc.

[0054] Examples of isocyanate compounds with three or more functions include adducts, biurets, and isocyanurates of difunctional isocyanate compounds. Examples of the above adducts include adducts with polyols of three or more functions, such as trimethylolpropane (TMP) or glycerin.

[0055] (E) It is preferable that the aromatic isocyanate compound having three or more functions be one or more selected from tolylene diisocyanate adducts and xylylene diisocyanate adducts. It is preferable that the adhesive composition contains (E) an aromatic isocyanate compound having three or more functions in a ratio of 0.1 to 10 parts by weight per 100 parts by weight of the total of (A) and (B).

[0056] The above adhesive composition contains (F) a silane coupling agent. It is preferable that (F) the silane coupling agent has one or more organic functional groups selected from the group consisting of epoxy groups, (meth)acryloxy groups, mercapto groups, amino groups, and polyether groups. In addition, an alkoxy oligomer (silicone alkoxy oligomer) oligomerized with these organic functional groups can also be preferably used as (F) the silane coupling agent.

[0057] Examples of silane coupling agents having an epoxy group include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethylmethyldimethoxysilane, 5,6-epoxyhexyltrimethoxysilane, 5,6-epoxyhexylmethyldimethoxysilane, etc.

[0058] Examples of silane coupling agents having a (meth)acryloxy group include 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, 3-(meth)acryloxypropyltriethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane, 3-(meth)acryloxypropyldimethylethoxysilane, and 3-(meth)acryloxypropyldimethylmethoxysilane.

[0059] Examples of silane coupling agents having a mercapto group include 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldiethoxysilane, and 3-mercaptopropyltriethoxysilane.

[0060] Examples of silane coupling agents having an amino group include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldiethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, 3-(methylamino)propyltrimethoxysilane, 3-(methylamino)propyltriethoxysilane, etc.

[0061] Silane coupling agents having polyether groups include, for example, Formula: R 1 -(OR 2 ) n -Si(OR 3 It is a perfluoropolyether group-containing silane coupling agent represented by )3. Here, R 1 is a perfluoroalkyl group such as C3F7. n R 2 may be identical or different, but is a perfluoroalkylene group such as CF2, C2F4, C3F6, or an alkylene group such as CH2, C2H4, C3H6. 3 is an alkyl group such as a methyl group or an ethyl group. n is an integer greater than or equal to 1.

[0062] It is preferable that the above adhesive composition contains (F) a silane coupling agent in a ratio of 0.1 to 3 parts by weight for every 100 parts by weight of the total of (A) and (B).

[0063] The above adhesive composition contains (G) an antistatic agent. It is preferable that the above adhesive composition contains (G) an antistatic agent in a ratio of 0.5 to 30 parts by weight per 100 parts by weight of the total of (A) and (B).

[0064] The above adhesive composition preferably contains (G) one or more ionic compounds with a melting point of 25°C or higher as an antistatic agent. As (G) the antistatic agent, an ionic compound with a melting point of 25°C or higher can be selected by selecting the cation and / or anion among ionic compounds having a cation and anion. (G) By having a melting point of 25°C or higher, the heat resistance of the antistatic agent can be maintained, and bleed-out on the surface of the adhesive layer and contamination of the substrate can be prevented.

[0065] (G) As a cation of the antistatic agent, one type selected from the group consisting of pyridinium, imidazolium, sulfonium, phosphonium, pyrrolidinium, guanidinium, ammonium, isouronium, thiouronium, piperidinium, pyrazolium, methylium, lithium, and morpholium may be used. Except when the cation is lithium, these cations may have one or more substituents. As substituents of the cation, organic groups such as alkyl groups may be used.

[0066] (G) Examples of anions for antistatic agents include inorganic or organic fluorogroup-containing anions. Here, a fluorogroup refers to a fluorine atom bonded to another atom constituting the anion. Examples of inorganic fluorogroup-containing anions include PF6 - , AsF6 - , SbF6 - , BF4 - , AlF4 - , (FSO2)2N - , FSO3 - Examples include the fluorogroup-containing anion. Organic fluorogroup-containing anions include the fluorogroup-containing sulfonate anion (RSO3 - ), fluorogroup-containing carboxylate anion (RCOO - ), fluorogroup-containing alkoxide or phenoxide anion (RO - ), fluorogroup-containing organic imide anion (R2N - ), fluorogroup-containing methide anion (R3C -), fluorogroup-containing organic borate anion (R4B - Examples include anions having an organic group containing a fluoro group as at least one of R.

[0067] (G) One or more organic groups of R in the anion of the antistatic agent may be alkyl groups, alkoxy groups, aromatic groups (aryl groups, aralkyl groups, etc.), alkyl carbonyl groups, aromatic carbonyl groups, alkyl sulfonyl groups, aromatic sulfonyl groups, etc. When the anion has two or more R groups, it may form a ring structure by having bonds between the two or more R groups.

[0068] (G) For an antistatic agent, it is preferable to include 0.5 to 30 parts by weight of one or more selected from the group of ionic compounds consisting of (G-1) to (G-3) for every 100 parts by weight of the total of (A) and (B).

[0069] (G-1) Examples of ammonium-based ionic compounds having a fluorogroup-containing anion include ionic compounds in which the fluorogroup-containing anion is selected from the group consisting of pentafluorobenzenesulfonate, hexafluorophosphate, bis(trifluoromethanesulfonyl)imide, bis(fluorosulfonyl)imide, and trilate. Ammonium-based ionic compounds have ammonium as a cation. The substituent of ammonium can be a substituent that does not contain a fluorogroup or a substituent that contains a fluorogroup.

[0070] (G-2) An ionic compound comprising a borate anion having a pentafluorophenyl group (C6F5 group) and a cation may be an ionic compound in which the cation is selected from the group of cations consisting of pyridinium, imidazolium, sulfonium, phosphonium, pyrrolidinium, guanidinium, ammonium, isouronium, thiouronium, piperidinium, pyrazolium, methylium, lithium, and morpholium. As for the borate anion having a C6F5 group, at least one of the four organic groups R must be a C6F5 group, and as a specific example, B(C6F5)4 - ...can be cited.

[0071] (G-3) As an ionic compound consisting of a nonafluorobutanesulfonate anion and a cation, examples include an ionic compound in which the cation is selected from the group consisting of pyridinium, imidazolium, phosphonium, sulfonium, pyrrolidinium, guanidinium, ammonium, isouronium, thiouronium, piperidinium, pyrazolium, methylium, lithium, and morpholium.

[0072] The above adhesive composition contains (H) a photoinitiator. (H) The photoinitiator is not particularly limited, but examples include acetophenone-based photoinitiators, benzoin-based photoinitiators, benzophenone-based photoinitiators, thioxantone-based photoinitiators, etc.

[0073] Examples of acetophenone-based photoinitiators include acetophenone, p-(tert-butyl)1',1',1'-trichloroacetophenone, chloroacetophenone, 2',2'-diethoxyacetophenone, hydroxyacetophenone, 2,2-dimethoxy-2'-phenylacetophenone, 2-aminoacetophenone, dialkylaminoacetophenone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 2-benzyl-2-(dimethylamino)-4'-morpholinobutyrophenone, etc.

[0074] Examples of benzoin-based photoinitiators include benzyl, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenyl-2-methylpropan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, benzyl dimethyl ketal, 2,2-dimethoxy-1,2-diphenylethane-1-one, etc.

[0075] Examples of benzophenone-based photoinitiators include benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, methyl-o-benzoylbenzoate, 4-phenylbenzophenone, hydroxylbenzophenone, hydroxylpropylbenzophenone, acrylbenzophenone, 4,4'-bis(dimethylamino)benzophenone.

[0076] Thioxantone-based photoinitiators include thioxantone, 2-chlorothioxantone, 2-methylthioxantone, diethylthioxantone, dimethylthioxantone, etc.

[0077] Other photoinitiators include α-acyloxime esters, benzyl-(o-ethoxycarbonyl)-α-monooxime, acylphosphine oxide, phenylglyoxylic acid esters, 3-ketocoumarin, 2-ethylanthraquinone, camperquinone, tetramethylthiuram sulfide, azobisisobutyronitrile, benzoyl peroxide, dialkyl peroxide, tert-butylperoxypivalate, etc.

[0078] It is preferable that the above adhesive composition contains (H) photoinitiator in a ratio of 0.1 to 5.0 parts by weight per 100 parts by weight of the total of (A) and (B).

[0079] In addition to the examples above, the adhesive composition of the embodiment may appropriately incorporate known additives as optional components, such as antioxidants, surfactants, curing accelerators, plasticizers, fillers, crosslinking catalysts, crosslinking retardants, curing retardants, processing aids, anti-aging agents, and antistatic agents. These may be used alone or in combination of two or more types.

[0080] It is preferable that the adhesive film formed by heat drying treatment from the adhesive composition of the embodiment has a 90° peel adhesion strength of 1 N / 25 mm or more on a PBO-treated silicon wafer. Here, PBO treatment refers to polybenzoxazole treatment. For the adhesive film used to test adhesion strength, for example, an adhesive layer with a thickness of 20 μm may be laminated onto a PEEK substrate with a thickness of 27 μm. Meanwhile, PEEK is a polyetheretherketone resin.

[0081] In addition, the adhesive film formed by the above heat drying treatment preferably has a 90° peel adhesion strength of 0.5 N / 25 mm or less on a PBO-treated silicon wafer after UV irradiation at a rate of 3000 mJ with a substrate (silicon wafer) of diameter 30.48 cm (12 inches) using a metal halide lamp or a 365 nm wavelength LED-UV lamp after the heat drying treatment (before the heat treatment described later, which involves heating at 240°C for 5 minutes and additionally heating at 165°C for 2.5 hours). It is more preferable that the adhesion strength be 0.3 N / 25 mm or less.

[0082] In addition, the adhesive film formed by the above heat drying treatment preferably has a 90° peel adhesion strength of 0.5 N / 25 mm or less on a PBO-treated silicon wafer after a test performed by UV irradiating a substrate (silicon wafer) with a diameter of 30.48 cm (12 inches) at a rate of 3000 mJ with a metal halide lamp or a 365 nm wavelength LED-UV lamp after the heat drying treatment, heating at 240°C for 5 minutes, and additionally heating at 165°C for 2.5 hours. It is more preferable that the adhesion strength be 0.3 N / 25 mm or less.

[0083] In addition, it is preferable that the adhesive film formed by the above heat drying treatment has a 90° peel adhesion strength of 0.5 N / 25 mm or more on BA-treated stainless steel after a test performed by UV irradiating a substrate (BA-treated stainless steel) with a diameter of 30.48 cm (12 inches) with a metal halide lamp or a 365 nm wavelength LED-UV lamp at a rate of 3000 mJ after the heat drying treatment, heating at 240°C for 5 minutes, and additionally heating at 165°C for 2.5 hours. Here, BA treatment refers to bright annealing treatment.

[0084] The surface resistivity of the adhesive layer after peeling from the silicon wafer is 1.0 × 10⁻⁶ +10 It is preferable that Ω / □ be less than or equal to this. By doing so, the peeling charge of the adhesive film and the substrate can be suppressed. The silicon wafer used for measuring the surface resistivity may be the same as the substrate (PBO-treated silicon wafer) used for measuring the adhesion force.

[0085] It is desirable that the adhesive film does not contaminate the surface of the silicon wafer after peeling. By doing so, surface contamination of the silicon wafer or the substrate can be prevented.

[0086] An adhesive layer made of the adhesive composition of the embodiment can be used in a film sheet. FIG. 1 shows an example in which the adhesive layer (11) of a film sheet (10) is laminated to a substrate (20). It is preferable that the film sheet (10) has the adhesive layer (11) on one side of a substrate (12).

[0087] The substrate (12) is preferably a heat-resistant substrate with a thickness of 25 μm or more. As a heat-resistant substrate, it is selected from polyimide-based film, polyetheretherketone (PEEK), polyethylene naphthalate (PEN), polyamide-based film, and polystyrene-based film.

[0088] For the substrate (12), it is desirable to select a material with high heat resistance so as to meet the requirements of the semiconductor processing process. For polyamide-based films and polystyrene-based films, examples include aromatic polyamide, syndiotactic polystyrene (SPS), etc., which have higher heat resistance than general-purpose resins (nylon or general-purpose polystyrene).

[0089] The film sheet (10) can be used in semiconductor processing processes such as wafer level packaging (WLP). The adhesive layer (11) is preferably bonded to a substrate (20) in a cross-linked state where the (meth)acrylic polymer included in the adhesive composition is cross-linked using (E) an aromatic isocyanate compound with three or more functional groups as a cross-linking agent.

[0090] In addition, it is desirable that the film sheet (10) has reduced adhesion to the silicon wafer due to ultraviolet (UV) irradiation. In addition, it is desirable that the adhesion to stainless steel is maintained at a predetermined level or higher even after ultraviolet (UV) irradiation.

[0091] Before the film sheet (10) is laminated to the substrate (20), a release film (separator) may be used to protect the adhesive surface of the adhesive layer (11). As the release film, a resin film such as a polyester film may be used. The release film may be treated with a release agent, a coating agent, an anti-fouling treatment, or an antistatic treatment.

[0092] Although the present invention has been described above based on preferred embodiments, the present invention is not limited to the embodiments described above, and various modifications are possible within the scope of not departing from the essence of the present invention. Modifications may include the addition, substitution, omission, or other changes of components in each embodiment.

[0093] Examples

[0094] The present invention will be specifically explained below through examples.

[0095] <Manufacture of Acrylic Polymers>

[0096] Nitrogen gas was introduced into a reaction apparatus equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen inlet tube to replace the air inside the reaction apparatus with nitrogen gas. Then, the monomers shown in Table 1 were added such that the total weight of (A) and (B) was 100 parts, and 60 parts by weight of a solvent (ethyl acetate) was added. Subsequently, 0.1 parts by weight of azobisisobutyronitrile as a photoinitiator was added dropwise over 2 hours, and the mixture was reacted at 65°C for 6 hours to obtain an acrylic polymer solution. The weight average molecular weight (Mw) of the acrylic polymer is shown in Table 1.

[0097]

[0098] The meanings of the abbreviation symbols used in Table 1 (compound names, etc.) are as follows. Also, the numbers following these abbreviation symbols in Table 1 are parts by weight per 100 parts by weight of the total of (A) and (B).

[0099] In Table 1, for group (A), n-butyl acrylate (BA), ethyl acrylate (EA), 2-ethylhexyl acrylate (2EHA), methyl acrylate (MA), isooctyl acrylate (IOA), isobutyl acrylate (IBA), and n-butyl methacrylate (BMA) were used.

[0100] In addition, for group (B), N-vinylpyrrolidone (NVP), N,N-diethylacrylamide (DEAA), N,N-dimethylacrylamide (DMAA), N,N-diisopropylacrylamide (DIPAA), and N-[3-(dimethylamino)propyl]methacrylamide (DMAPMA) were used.

[0101] In addition, for group (C), 8-hydroxyoctyl acrylate (8HOA), 6-hydroxyhexyl acrylate (6HHA), 4-hydroxybutyl acrylate (4HBA), 2-hydroxyethyl acrylate (HEA), N-hydroxymethylacrylamide (HMAA), and N-hydroxyethylacrylamide (HEAA) were used.

[0102] In addition, (X) group is a monomer containing a carboxyl group, and acrylic acid (AAc) was used in Comparative Example 4.

[0103] <Preparation of Adhesive Composition and Adhesive Layer>

[0104] To the acrylic polymer solution described above, the additives shown in Table 2 were added and stirred to obtain an adhesive composition. After applying this adhesive composition onto a release film made of a silicone resin-coated polyethylene terephthalate (PET) film, the solvent was removed by drying at 90°C, and then an adhesive layer was obtained by aging for 7 days under an atmosphere of 23°C and 50% RH. For the adhesive film used to test the adhesive strength, an adhesive layer with a thickness of 20 μm may be laminated onto a PEEK substrate with a thickness of 27 μm.

[0105]

[0106] The meanings of the abbreviation symbols used in Table 2 (compound names, etc.) are as follows. Also, the numbers following these abbreviation symbols in Table 2 are parts by weight per 100 parts by weight of the total of (A) and (B).

[0107] In Table 2, for group (D), tetrofunctional pentaerythritol tetraacrylate (D-1), polypentaerythritol polyacrylate with 6 or more functions (D-2), tetrofunctional ditrimethylolpropane tetraacrylate (D-3), hexafunctional dipentaerythritol hexaacrylate (D-4), difunctional 1,6-hexanediol diacrylate (D-5), and trifunctional pentaerythritol triacrylate (D-6) were used.

[0108] In addition, for group (E), Takenate (registered trademark) D-101, Takenate (registered trademark) D-110N, and Coronate (registered trademark) HL were used. “D-101” is a trimethylolpropane (TMP) adduct of tolylene diisocyanate (TDI), “D-110N” is a trimethylolpropane (TMP) adduct of xylylene diisocyanate (XDI), and “HL” is an adduct of hexamethylene diisocyanate (HDI).

[0109] In addition, for group (F), a silane coupling agent having an epoxy group as “F-1” (product name: X-24-9590), a silane coupling agent having a mercapto group as “F-2” (product name: X-12-1154), and a silane coupling agent having an acryloxy group as “F-3” (product name: KBM-503) were used.

[0110] In addition, for group (G), as “G-1-1”, tetrabutylammonium triplate (melting point 113°C); as “G-1-2”, methyltri-n-butylammonium bis(trifluoromethanesulfonyl)imide (melting point 27°C); as “G-1-3”, trimethylhexylammonium bis(trifluoromethanesulfonyl)imide (melting point 27°C); as “G-1-4”, 4-methyl-1-hexylpyridinium bis(trifluoromethanesulfonyl)imide (melting point less than 25°C); as “G-2-1”, triphenylmethylium tetrakis(pentafluorophenyl)borate (melting point 183°C); as “G-2-2”, (methoxymethyl)triphenylphosphonium tetrakis(pentafluorophenyl)borate (melting point 149°C); and as “G-2-3”, 1-ethyl-3-methylimidazolium tetrafluoroborate (melting point 15°C), lithium nonafluorobutanesulfonate (melting point 370°C) as "G-3-1", 4-methyl-1-octylpyridinium nonafluorobutanesulfonate (melting point 62°C) as "G-3-2", and 3-methyl-1-octylpyridinium nonafluorobutanesulfonate (melting point 41°C) as "G-3-3".

[0111] In addition, for group (H), alkylphenone-based OMNIRAD (registered trademark) 184 was used as “H-1”, alkylphenone-based OMNIRAD (registered trademark) 369 as “H-2”, oxime ester-based IRGACURE (registered trademark) OXE01 as “H-3”, and acylphosphine oxide-based OMNIRAD (registered trademark) TPO as “H-4”.

[0112] <Manufacturing of Film Sheets>

[0113] A film sheet was manufactured by transferring an adhesive layer formed on a release film onto a heat-resistant substrate shown in Table 3. The materials of the heat-resistant substrate are polyetheretherketone (PEEK), polyethylene naphthalate (PEN), polyamide (PA)-based film, and polystyrene (PS)-based film.

[0114] The initial adhesion strength shown in Table 3 was measured as the 90° peel adhesion strength after laminating the adhesive layer of the film sheet to the PBO-treated wafer. In the adhesion strength of Table 3, it is indicated as "Initial".

[0115] The adhesion strength after UV irradiation shown in Table 3 was measured as the 90° peel adhesion strength after laminating an adhesive layer of a film sheet onto a PBO-treated wafer, irradiating a substrate with a diameter of 30.48 cm (12 inches) with a metal halide lamp or a 365 nm wavelength LED-UV lamp at a rate of 3000 mJ. In the adhesion strength in Table 3, "UV" is indicated.

[0116] The adhesion strength after UV irradiation and heating shown in Table 3 was measured as the 90° peel adhesion strength after laminating an adhesive layer of a film sheet onto a substrate selected from a PBO-treated wafer or BA-treated stainless steel (SUS), UV irradiating a substrate with a diameter of 30.48 cm (12 inches) with a metal halide lamp or a 365 nm wavelength LED-UV lamp at a rate of 3000 mJ, heating at 240°C for 5 minutes, and additionally heating at 165°C for 2.5 hours. In the adhesion strength of Table 3, "UV + heating" was indicated.

[0117]

[0118] The reworkability shown in Table 3 was rated as good (○) if the adhesive strength of the film sheet after UV irradiation and heating was less than 0.3 N / 25 mm, possible (△) if it was 0.3 N / 25 mm or more and less than 3 N / 25 mm, and impossible (×) if it was 3 N / 25 mm or more.

[0119] The surface resistivity shown in Table 3 was measured by applying a resistivity meter to the adhesive layer after peeling from the substrate (PBO-treated wafer). The measurement results are [m × 10 +n 」 was expressed in the manner of “mE+n” (where m and n are positive real numbers).

[0120] The anti-contamination properties shown in Table 3 were determined by measuring the adhesion strength of the film sheet after UV irradiation and heating, and then visually checking whether the adhesive component had migrated to the surface of the substrate (PBO-treated wafer) and caused contamination. No contamination at all on the substrate was rated as Good (○), thin contamination on a part or the entire substrate was rated as Possible (△), and contamination on the entire surface was rated as Poor (×).

[0121] In the film sheets of Examples 1 to 9, (1) the initial adhesion strength to a PBO-treated wafer was 1 N / 25 mm or more, (2) the adhesion strength to a PBO-treated wafer after UV irradiation was 0.3 N / 25 mm or less, (3) the adhesion strength to a PBO-treated wafer after UV irradiation and heating was 0.5 N / 25 mm or less, and (4) the adhesion strength to a BA-treated SUS after UV irradiation and heating was 0.5 N / 25 mm or more. In addition, the film sheets of Examples 1 to 9 had excellent antistatic performance and anti-contamination properties.

[0122] None of the film sheets of Comparative Examples 1 to 9 satisfied all the requirements of (1), (3), and (4) described above. In addition, the film sheets of Comparative Examples 1 to 9 were also poor in terms of antistatic performance and stain resistance.

[0123] In Comparative Example 1, the unsaturated double bond compound is a difunctional acrylate, and the adhesive composition does not contain (G) an antistatic agent.

[0124] In Comparative Example 2, the Mw of the (meth)acrylic polymer is 480,000, and the adhesive composition does not contain (G) an antistatic agent.

[0125] In Comparative Example 3, (B) a copolymerizable nitrogen-containing vinyl monomer is not copolymerized with a (meth)acrylic polymer, and (G) the melting point of the antistatic agent is low.

[0126] In Comparative Example 4, a copolymer monomer containing (C) a hydroxyl group is not copolymerized with a (meth)acrylic polymer, and the adhesive composition does not contain (G) an antistatic agent.

[0127] In Comparative Example 5, the adhesive composition does not contain (F) a silane coupling agent, and (G) the melting point of the antistatic agent is low.

[0128] In Comparative Example 6, the unsaturated double bond compound is a trifunctional acrylate, and the adhesive composition does not contain (G) an antistatic agent.

[0129] In Comparative Example 7, the crosslinking agent is an aliphatic isocyanate compound, and (G) the proportion of the antistatic agent is insufficient.

[0130] In Comparative Example 8, the adhesive composition does not include (G) an antistatic agent and (H) a photoinitiator.

[0131] In Comparative Example 9, the adhesive composition does not include (G) an antistatic agent. Explanation of the symbols

[0132] 10… film sheet, 11… adhesive layer, 12… substrate, 20… adherend.

Claims

Claim 1 An adhesive composition comprising (meth)acrylic polymer, an unsaturated double bond compound having four or more functional groups, a crosslinking agent, (F) a silane coupling agent, (G) an antistatic agent, and (H) a photoinitiator, wherein the (meth)acrylic polymer is a copolymer having a weight average molecular weight of 1 million to 3.5 million, comprising (A) one or more alkyl (meth)acrylates having C1 to C18 carbon atoms in the alkyl group, a copolymerizable monomer not containing a carboxyl group, (B) one or more copolymerizable nitrogen-containing vinyl monomers, and (C) one or more copolymerizable monomers containing a hydroxyl group, and the unsaturated double bond compound is (D) one or more selected from acrylates having four or more unsaturated double bonds within the molecule, and the adhesive composition comprises the alkyl (meth)acrylate having C1 to C18 carbon atoms in the alkyl group and the (B) A pressure-sensitive adhesive composition characterized by containing, in proportion to 100 parts by weight of copolymerizable nitrogen-containing vinyl monomers, (E) an aromatic isocyanate compound with three or more functions as a crosslinking agent in an amount of 0.1 to 10 parts by weight, (F) a silane coupling agent in an amount of 0.1 to 3 parts by weight, (G) an antistatic agent in an amount of 0.5 to 30 parts by weight of one or more ionic compounds with a melting point of 25°C or higher, and (H) a photoinitiator in an amount of 0.1 to 5.0 parts by weight, and containing (A) an alkyl (meth)acrylate having C1 to C18 carbon atoms in an alkyl group and (B) copolymerizable nitrogen-containing vinyl monomers in an amount of 40 parts by weight or more of n-butyl acrylate. Claim 2 In claim 1, the adhesive film, wherein a 20 μm thick adhesive layer formed by heat-drying treatment from the adhesive composition is laminated onto a 27 μm thick polyetheretherketone substrate, has a 90° peel adhesion strength of 1 N / 25 mm or more on a polybenzoxazole-treated silicon wafer, and subsequently, the adhesion strength after a test performed by UV irradiating the silicon wafer with a diameter of 30.48 cm with a metal halide lamp or a 365 nm wavelength LED-UV lamp at a rate of 3000 mJ, heating at 240°C for 5 minutes, and additionally heating at 165°C for 2.5 hours is 0.5 N / 25 mm or less, and the surface resistivity of the surface of the adhesive layer after peeling from the silicon wafer is 1.0 × 10⁻⁶ +10 An adhesive composition characterized by having an Ω / □ or less, a 90° peel adhesive strength of the adhesive film against bright annealed stainless steel of 0.5 N / 25 mm or more when tested in the same way as the silicon wafer, and not contaminating the surface of the silicon wafer after peeling. Claim 3 An adhesive composition according to claim 1 or 2, characterized in that the (meth)acrylic polymer comprises, in a ratio of 0.1 to 5 parts by weight to 100 parts by weight, the sum of (A) 70 to 95 parts by weight of one or more alkyl (meth)acrylates having C1 to C18 carbon atoms in the alkyl group and (B) 5 to 30 parts by weight of one or more nitrogen-containing vinyl monomers that do not contain hydroxyl groups as copolymerizable nitrogen-containing vinyl monomers. Claim 4 An adhesive composition according to claim 1 or 2, wherein the (meth)acrylic polymer comprises, in a ratio of 0.1 to 5 parts by weight, one or more selected from hydroxyl group-containing (meth)acrylate and hydroxyl group-containing (meth)acrylamide as (C) copolymerizable monomer containing a hydroxyl group, based on a total weight of 100 parts by weight of (A) an alkyl (meth)acrylate having C1 to C18 carbon atoms in the alkyl group and (B) copolymerizable nitrogen-containing vinyl monomer. Claim 5 In claim 1 or 2, the ionic compound having a melting point of 25°C or higher as (G) an antistatic agent comprises: (G-1) an ammonium-based ionic compound having a fluorogroup-containing anion, wherein the fluorogroup-containing anion is one selected from the group consisting of pentafluorobenzenesulfonate, hexafluorophosphate, bis(trifluoromethanesulfonyl)imide, bis(fluorosulfonyl)imide, and trilate; (G-2) an ionic compound comprising a borate anion having a pentafluorophenyl group and a cation, wherein the cation is one selected from the group consisting of pyridinium, imidazolium, sulfonium, phosphonium, pyrrolidinium, guanidinium, ammonium, isouronium, thiouronium, piperidinium, pyrazolium, methylium, lithium, and morpholinium; and (G-3) a nonafluorobutanesulfonate anion and a cation. An adhesive composition characterized by comprising 0.5 to 30 parts by weight of one or more selected from a group of ionic compounds, wherein the cation is an ionic compound, and the cation is selected from the group consisting of pyridinium, imidazolium, phosphonium, sulfonium, pyrrolidinium, guanidinium, ammonium, isouronium, thiouronium, piperidinium, pyrazolium, methylium, lithium, and morpholium. Claim 6 An adhesive composition according to claim 1 or 2, wherein the copolymerizing monomer containing (C) a hydroxyl group is one or more selected from the group of compounds consisting of 8-hydroxyoctyl(meth)acrylate, 6-hydroxyhexyl(meth)acrylate, 4-hydroxybutyl(meth)acrylate, 2-hydroxyethyl(meth)acrylate, N-hydroxy(meth)acrylamide, N-hydroxymethyl(meth)acrylamide, and N-hydroxyethyl(meth)acrylamide. Claim 7 An adhesive composition according to claim 1 or 2, wherein, based on 100 parts by weight of the total of (A) an alkyl (meth)acrylate having C1 to C18 carbon atoms in an alkyl group and (B) a copolymerizable nitrogen-containing vinyl monomer, (D) an acrylate having four or more unsaturated double bonds in its molecule, the adhesive composition comprises 5 to 30 parts by weight of one or more acrylate compounds selected from the group consisting of pentaerythritol tetraacrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol polyacrylate, and polypentaerythritol polyacrylate. Claim 8 An adhesive composition according to claim 1 or 2, characterized in that the (E) aromatic isocyanate compound having three or more functions is one or more selected from tolylene diisocyanate adducts and xylylene diisocyanate adducts. Claim 9 An adhesive composition according to claim 1 or 2, characterized in that the (F) silane coupling agent has, as an organic functional group, one or more selected from the group consisting of an epoxy group, a (meth)acryloxy group, a mercapto group, an amino group, and a polyether group. Claim 10 A film sheet characterized by having an adhesive layer composed of the adhesive composition of claim 1 or 2. Claim 11 A film sheet according to claim 10, characterized in that the substrate of the adhesive layer is a heat-resistant substrate with a thickness of 25 μm or more. Claim 12 A film sheet according to claim 11, characterized in that the heat-resistant substrate is selected from a polyimide-based film, a polyetheretherketone film, a polyethylene naphthalate film, a polyamide-based film, and a polystyrene-based film. Claim 13 A film sheet characterized by being used in a semiconductor processing process in claim 10. Claim 14 A film sheet according to claim 13, characterized in that, as the semiconductor processing process, it is used in a wafer-level packaging process.

Images