Thin film, laminated body, semiconductor wafer with thin film layer, semiconductor mounting substrate with thin film layer, and semiconductor device

Abstract

A film comprising: a propylene-containing resin (A) having a constituent unit represented by the following formula (1) at the terminal of the molecule; a radical polymerizable resin or compound (B) other than the propylene-containing resin (A); and a curing accelerator (C), wherein the radical polymerizable resin or compound (B) comprises at least one selected from the group consisting of a maleimide group and a citraconimide group. In formula (1), ‑* represents an atomic bond.

Description

Technical Field

[0001] The present invention relates to a thin film, a laminate using the thin film, a semiconductor wafer with a thin film layer, a semiconductor mounting substrate with a thin film layer, and a semiconductor device. More specifically, the present invention relates to a thin film useful as a pre-underfill material. Background Art

[0002] In recent years, as semiconductor devices have become smaller and more powerful, flip-chip mounting has attracted attention as a method of mounting a semiconductor chip (hereinafter, sometimes abbreviated as a "chip") on a semiconductor mounting substrate (hereinafter, sometimes abbreviated as a "substrate"). In flip-chip mounting, a method is common in which a chip is bonded to a substrate and then a bottom fill material is filled in the gap between the chip and the substrate and cured. However, as semiconductor devices have become smaller and more powerful, the pitch between electrodes arranged on the chip and the gap between electrodes have become narrower, and the long time required to fill the bottom fill material has led to a deterioration in operability and the occurrence of poor filling such as non-filling, which has become a problem. In response to this, a method is being studied in which a chip or substrate is pre-applied with a bottom fill material and then the chip and the substrate are bonded and the bottom fill material is filled at the same time.

[0003] The bottom filling material is a component that is in direct contact with the chip and the substrate. Therefore, important properties required of the bottom filling material include suppressing the unfilled portion of the bottom filling between the chip and the substrate and the bottom filling material in the environment of manufacturing and using semiconductor devices (hereinafter sometimes referred to as "low voidage"); and good adhesion between the chip and the substrate and the bottom filling material (hereinafter sometimes abbreviated as "chip adhesion").

[0004] Patent Document 1 describes a pre-underfill material using a radical polymerizable monomer in a main resin. Patent Document 1 describes the blending of a silane coupling agent for the purpose of improving adhesion to a chip.

[0005] Patent Document 2 describes an underfill material containing an epoxy resin, an imidazole compound, and a maleimide compound.

[0006] Patent Document 3 describes a pre-underfill material using an epoxy compound and a flux component containing a carboxyl group, and mentions bonding.

[0007] Patent Document 4 describes a resin composition including a maleimide compound, an epoxy resin, and an epoxy resin curing agent as essential components, and describes that the resin composition after thermal curing has high adhesion.

[0008] Patent Document 5 describes a resin composition for a printed circuit board, which is used to form an insulating layer in the printed circuit board. The thermosetting resin composition contains a maleimide compound having a specific structure, a benzoxazine compound, and an inorganic filler (C).

[0009] Patent Document 6 describes an adhesive for electronic components that contains an aliphatic epoxy compound and a benzoxazine compound as a main curing agent and also contains a phenolic curing agent.

[0010] Patent document 7 describes an adhesive composition comprising: a thermosetting compound, a polymer containing a functional group that can react with the aforementioned thermosetting compound, and a thermosetting agent, wherein the adhesive composition has a melt viscosity of 10 Pa·s to 15000 Pa·s at the bonding temperature, a gel time of more than 10 seconds at the bonding temperature, and a gel time of 1 second to 10 seconds at 240°C.

[0011] Patent Document 8 discloses a method for producing a semiconductor device using a sheet-like thermosetting resin composition.

[0012] In addition, when a chip is joined to a substrate using easily oxidized metals such as solder and copper, a fluxing component derived from carboxylic acid or the like is sometimes added to the pre-applied bottom filling material in order to remove the metal oxide film that will hinder the joining from the joining portion and obtain a good metal joint.

[0013] Prior art literature

[0014] Patent Literature

[0015] Patent Document 1: Japanese Patent Application No. 2015-503220

[0016] Patent Document 2: Japanese Patent Application No. 2014-521754

[0017] Patent Document 3: Japanese Patent Application Publication No. 2013-112730

[0018] Patent Document 4: Japanese Patent Application Publication No. 2003-221443

[0019] Patent Document 5: Japanese Patent Application Publication No. 2016-196548

[0020] Patent Document 6: Japanese Patent Application Publication No. 2013-008800

[0021] Patent Document 7: Japanese Patent Application Publication No. 2011-157529

[0022] Patent Document 8: Japanese Patent Application Publication No. 2006-245242 Summary of the invention

[0023] Problem that the invention aims to solve

[0024] However, free radical polymerizable monomers generally cure quickly, and the mobility of the bonding site of the compounded silane coupling agent is controlled by the main resin that polymerizes before forming a sufficient number of bonds with the silanol groups on the chip surface. As a result, the pre-applied bottom fill material described in Patent Document 1 cannot obtain sufficient low voids and good chip adhesion between the substrate such as the chip and the printed circuit board and the bottom fill material. In addition, free radical polymerizable monomers cure quickly, so they cure before the resin composition is embedded in the unevenness existing on the chip surface. Therefore, the pre-applied bottom fill material described in Patent Document 1 also has the problem of not being able to fully obtain the anchoring effect useful in improving adhesion.

[0025] The material described in Patent Document 2 acts only on a polyimide passivation film, and therefore has a problem of having a narrow application range.

[0026] In the technology described in Patent Document 3, the carboxyl group-containing compound slightly reacts with the epoxy compound even at room temperature, and the fluxing activity decreases over time during storage. Therefore, the pre-applied underfill material described in Patent Document 3 has the problems of low bonding stability and lack of mass productivity.

[0027] In the technology described in Patent Document 4, the water absorption rate of maleimide resin is high, so there is a problem that the chip adhesion after moisture absorption treatment is greatly reduced. If the adhesion is insufficient, water will penetrate from the peeling interface, and the insulation reliability will be greatly reduced. In addition, it is difficult to achieve both low voids and chip adhesion using only maleimide resin.

[0028] Patent Document 5 does not describe flux activity, and also does not describe flux components. Therefore, the resin composition described in Patent Document 5 has a problem that good metal bonding cannot be achieved.

[0029] In Patent Document 6, although the epoxy compound has high adhesiveness, the epoxy compound also reacts with the flux component, and there is a problem that a flux activity sufficient to obtain good metal bonding cannot be obtained.

[0030] The adhesive composition of Patent Document 7 contains a thermosetting agent having fluxing properties, but epoxy compounds and polymers containing epoxy groups are used in the examples, which react at a temperature lower than the bonding temperature, so it is difficult to obtain sufficient fluxing activity.

[0031] Patent Document 8 also states that epoxy resin is suitable as the thermosetting resin contained in the thermosetting resin composition. However, as mentioned above, epoxy compounds also react with flux components and there is also a problem that flux activity sufficient to obtain good metal bonding cannot be obtained.

[0032] The present invention has been made in view of such problems, and provides a film, a laminate, a semiconductor wafer with a thin film layer, a semiconductor mounting substrate with a thin film layer, and a semiconductor device having excellent curability, low voiding properties, and die bonding properties.

[0033] Solutions for solving problems

[0034] The present inventors have conducted intensive studies to solve the above-mentioned problems and have found that a film comprising a specific acrylic group-containing resin (A), a specific radical polymerizable resin or compound (B), and a curing accelerator (C) can solve the above-mentioned problems, thereby achieving the present invention.

[0035] That is, the present invention includes the following contents. [1]

[0037] A film comprising: an propylene-containing resin (A) comprising a constituent unit represented by the following formula (1) at a terminal in the molecule; a radically polymerizable resin or compound (B) other than the propylene-containing resin (A); and a curing accelerator (C), wherein the radically polymerizable resin or compound (B) comprises at least one selected from the group consisting of a maleimide group and a citraconimide group.

[0038]

[0039] (In formula (1), -* represents an atomic bond.) [2]

[0041] The film according to [1], wherein the mass average molecular weight of the acrylic group-containing resin (A) is 300 to 10,000. [3]

[0043] The film according to [1] or [2], wherein the propylene group-containing resin (A) comprises a resin represented by the following formula (2).

[0044]

[0045] (In formula (2), W each independently represents a hydrocarbon group having 6 to 15 carbon atoms which may have a substituent. U each independently represents a hydrogen atom or an alkenyl group having 2 to 6 carbon atoms. 1 Represents the number of repetitions, whose average value is a real number between 1 and 20. ). [4]

[0047] The film according to any one of [1] to [3], wherein the propylene group-containing resin (A) comprises a resin represented by the following formula (3).

[0048]

[0049] In formula (3), Y each independently represents a hydrocarbon group having 1 to 6 carbon atoms. X each independently represents a hydrogen atom or an alkenyl group having 2 to 6 carbon atoms. 2 Represents the number of repetitions, whose average value is a real number between 1 and 20. ). [5]

[0051] A film according to any one of [1] to [4], wherein the radical polymerizable resin or compound (B) comprises at least one selected from the group consisting of 2,2-bis[4-(4-maleimidephenoxy)phenyl]propane, a maleimide compound represented by the following formula (4), a maleimide compound represented by the following formula (5), a maleimide compound represented by the following formula (6), a maleimide compound represented by the following formula (7), a maleimide compound represented by the following formula (8), and a maleimide compound represented by the following formula (9).

[0052]

[0053] (In formula (4), R 1 Each independently represents a hydrogen atom or a methyl group, n 3 represents an integer from 1 to 10. ).

[0054]

[0055] (In formula (5), n 4 represents an integer from 1 to 30. ).

[0056]

[0057] (In formula (6), R 2 Each independently represents a hydrogen atom, a methyl group, or an ethyl group, and R 3 Each independently represents a hydrogen atom or a methyl group. ).

[0058]

[0059] (In formula (7), R 4 Each independently represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a phenyl group, l each independently represents an integer of 1 to 3, and n 5 represents an integer from 1 to 10. ).

[0060]

[0061] (In formula (8), R 5 and R 7 Each independently represents a hydrocarbon group consisting of 8 or more atoms connected in a straight chain, R 6 Each independently represents a substituted or unsubstituted cyclic hydrocarbon group having 4 to 10 atoms constituting the ring and optionally containing a hetero atom, n 6 represents an integer from 1 to 10. ).

[0062]

[0063] (In formula (9), R 8 Each independently represents an alkylene group, R 9 Each independently represents an alkylene group, a group represented by the following formula (10), a group represented by the formula "-SO2-", a group represented by "-CO-", a group represented by the following formula (11), an oxygen atom, or a single bond, and n 7 represents an integer from 1 to 10. ).

[0064]

[0065] (In formula (10), Z is an alkylene group or a hydrocarbon group having 6 to 30 carbon atoms and containing an aromatic ring, n 8 Represents an integer from 0 to 5. ).

[0066] [6]

[0068] The film according to any one of [1] to [5], wherein the ratio of the acrylic group in the acrylic group-containing resin (A) to the polymerizable functional group in the radical polymerizable resin or compound (B) (acrylic group:polymerizable functional group) is 1:1 to 1:7. [7]

[0070] The film according to any one of [1] to [6], wherein the curing accelerator (C) comprises at least one selected from the group consisting of a thermal radical polymerization initiator (D) and an imidazole compound (E). [8]

[0072] The film according to [7], wherein the 10-hour half-life temperature of the thermal radical polymerization initiator (D) is 100° C. or higher. [9]

[0074] The film according to [7] or [8], wherein the thermal radical polymerization initiator (D) contains an organic peroxide.

[10]

[0076] The film according to any one of [7] to [9], wherein the thermal radical polymerization initiator (D) has a peroxyester, peroxyketal, dialkyl peroxide, or hydroperoxide skeleton.

[11]

[0078] The film according to any one of [7] to

[10] , wherein the thermal radical polymerization initiator (D) comprises at least one selected from the group consisting of diisopropylbenzene peroxide, di(2-tert-butylperoxyisopropyl)benzene, 1,1,3,3-tetramethylbutyl hydroperoxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)3-hexyne, and tert-butyl hydroperoxide.

[12]

[0080] The film according to any one of [1] to

[11] , wherein the content of the curing accelerator (C) is 0.05 to 10 parts by mass based on 100 parts by mass of the total of the acrylic group-containing resin (A) and the radical polymerizable resin or compound (B).

[13]

[0082] The film according to any one of [1] to

[12] , further comprising a thermosetting compound (F) other than the acrylic group-containing resin (A) and the radical polymerizable resin or compound (B).

[14]

[0084] The film according to

[13] , wherein the thermosetting compound (F) has a molecular weight of 400 or more.

[15]

[0086] The film according to

[13] or

[14] , wherein the thermosetting compound (F) contains a benzoxazine compound.

[16]

[0088] The film according to

[15] , wherein the benzoxazine compound comprises at least one selected from the group consisting of a compound represented by the following formula (12), a compound represented by the following formula (13), a compound represented by the following formula (14), and a compound represented by the following formula (15).

[0089]

[0090] (In formula (12), R 10 Each independently represents an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group, and R 11 represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, a cycloalkyl group, or a monovalent to tetravalent organic group represented by the following general formulae (a) to (t), n 9 represents an integer from 1 to 4. ).

[0091]

[0092] (In formula (13), R 12 Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group, and R 13 represents an aryl group, an aralkyl group, an alkenyl group, an alkyl group, a cycloalkyl group, or a monovalent to tetravalent organic group represented by the following general formulae (a) to (t), n 10 represents an integer from 1 to 4. ).

[0093]

[0094] (In formula (14), R 14 represents an alkyl group, a cycloalkyl group, or a phenyl group which may have a substituent. )

[0095]

[0096] (In formula (15), R 15 represents an alkyl group, a cycloalkyl group, or a phenyl group which may have a substituent. )

[0097]

[0098]

[0099] (In formulas (a) to (t), R a represents an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group, and R b represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group. ).

[17]

[0101] The film according to

[14] or

[15] , wherein the benzoxazine compound comprises at least one selected from the group consisting of a compound represented by the following formula (23) and a compound represented by the following formula (24).

[0102]

[0103] (In formula (23), R 16 Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group, o each independently represents an integer of 1 to 4, and R 17 Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group, each independently represents an integer of 1 to 4, and T 1 represents an alkylene group, a group represented by the following formula (10), a group represented by the formula "-SO2-", a group represented by "-CO-", an oxygen atom, or a single bond. ).

[0104]

[0105] (In formula (24), R 18 Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group, q each independently represents an integer of 1 to 3, and R 19 Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group, each independently represents an integer of 1 to 5, and T 2 represents an alkylene group, a group represented by the following formula (10), a group represented by the formula "-SO2-", a group represented by "-CO-", an oxygen atom, or a single bond. ).

[0106]

[0107] (In formula (10), Z is an alkylene group or a hydrocarbon group having 6 to 30 carbon atoms and containing an aromatic ring, n 8 Represents an integer from 0 to 5. ).

[18]

[0109] The film according to any one of

[13] to

[17] , wherein the content of the thermosetting compound (F) is 1 to 100 parts by mass based on 100 parts by mass of the total of the acrylic group-containing resin (A) and the radical polymerizable resin or compound (B).

[19]

[0111] The film according to any one of [1] to

[18] , further comprising an inorganic filler (G).

[20]

[0113] The film according to

[19] , wherein the average particle size of the inorganic filler (G) is 3 μm or less. [twenty one]

[0115] The thin film according to

[19] or

[20] , wherein the inorganic filler (G) comprises at least one selected from the group consisting of silica, aluminum hydroxide, aluminum oxide, boehmite, boron nitride, aluminum nitride, magnesium oxide, and magnesium hydroxide. [twenty two]

[0117] The thin film according to any one of

[19] to

[21] , wherein the inorganic filler (G) is silicon dioxide. [twenty three]

[0119] The film according to any one of

[19] to

[22] , wherein the content of the inorganic filler (G) is 500 parts by mass or less per 100 parts by mass of the total of the acrylic group-containing resin (A) and the radical polymerizable resin or compound (B). [twenty four]

[0121] The thin film according to any one of [1] to

[23] , further comprising an organic compound (H) having a fluxing function.

[25]

[0123] The film according to

[24] , wherein the content of the organic compound (H) having a fluxing function is 5 to 80 parts by mass based on 100 parts by mass of the total of the acrylic group-containing resin (A) and the radical polymerizable resin or compound (B).

[26]

[0125] The film according to any one of [1] to

[25] , which has a thickness of 10 μm to 100 μm.

[27]

[0127] The film according to any one of [1] to

[26] , which is used for pre-application of an underfill material.

[28]

[0129] A laminate comprising: a supporting substrate; and a layer comprising the thin film according to any one of [1] to

[27] laminated on the supporting substrate.

[29]

[0131] A semiconductor wafer with a thin film layer comprises: a semiconductor wafer and the stacked body described in

[28] stacked on the semiconductor wafer, wherein the layer including the thin film is stacked on the semiconductor wafer.

[30]

[0133] A semiconductor mounting substrate with a thin film layer, comprising: a semiconductor mounting substrate; and the stacked body described in

[28] stacked on the semiconductor mounting substrate, wherein the layer including the thin film is stacked on the semiconductor mounting substrate.

[31]

[0135] A semiconductor device comprising: the semiconductor wafer with a thin film layer described in

[29] and / or the semiconductor mounting substrate with a thin film layer described in

[30] .

[0136] Effects of the Invention

[0137] According to the present invention, a film, a laminate, a semiconductor wafer with a thin film layer, a semiconductor mounting substrate with a thin film layer, and a semiconductor device having excellent curability, low voiding properties, and die bonding properties can be obtained. DETAILED DESCRIPTION

[0138] Hereinafter, a mode for carrying out the present invention (hereinafter, simply referred to as "this embodiment") will be described. It should be noted that the following this embodiment is an example for describing the present invention, and the present invention is not limited to this embodiment.

[0139] According to one embodiment of the present invention, the film comprises: a specific acrylic resin (A), a specific free radical polymerizable resin or compound (B) and a curing accelerator (C). From the perspective of more effectively and reliably exerting the effects of the present invention, the film is preferably used for pre-application of the bottom filling material.

[0140] Another aspect of the present embodiment is a film further comprising a thermosetting compound (F).

[0141] Another aspect of the present embodiment is a thin film further including an inorganic filler (G).

[0142] Another aspect of the present embodiment is a thin film further including an organic compound (H) having a fluxing function.

[0143] It should be noted that, in the present embodiment, “(meth)acryloyl” refers to both “acryloyl” and its corresponding “methacryloyl”, “(meth)acrylic acid” refers to both “acrylic acid” and its corresponding “methacrylic acid”, “(meth)acrylate” refers to both “acrylate” and its corresponding “methacrylate”, and “(meth)allyl” refers to both “allyl” and its corresponding “methallyl”.

[0144] [film]

[0145] The film of the present embodiment is a film suitable for use as a pre-underfill material used in flip chip mounting of a chip, and comprises: an propylene-containing resin (A) containing a constituent unit represented by formula (1) at the end of the molecule, a radical polymerizable resin or compound (B) other than the propylene-containing resin (A), and a curing accelerator (C). The radical polymerizable resin or compound (B) contains at least one selected from the group consisting of a maleimide group and a citraconimide group.

[0146] The resin composition of the present embodiment may contain at least any one of a thermosetting compound (F), an inorganic filler (G), and an organic compound (H) having a fluxing function.

[0147] In the present embodiment, the reason why a film suitable for pre-application of bottom filling material with excellent curability, low voids, and chip adhesion can be obtained is still uncertain, but the present inventors presume as follows. In the film of the present embodiment, by using a propylene-containing resin (A) containing a propylene group at the end of the molecule, it has an appropriate melt viscosity, and promotes the reaction of propylene groups with each other, and the reaction of maleimide groups and / or citraconimide groups contained in the free radical polymerizable resin or compound (B) with propylene groups. As a result, the film of the present embodiment has an appropriate melt viscosity, and the crosslinking density of the cured product is increased due to the excellent curability, so that the film is spread between the chip and the substrate and the bottom filling material, and the unfilled part of the bottom filling can be suppressed. Therefore, low voids and excellent chip adhesion are obtained. In particular, the present inventors found that in flip-chip mounting, in order to suppress the voids generated during the thermal compression bonding of the chip and the substrate with the bottom filling material, it is important to have the melt viscosity of the film at the curing start temperature and the temperature during the thermal compression bonding. The film of the present embodiment has a moderate melt viscosity at the temperature during thermocompression bonding, and has excellent curability, so the resin composition melted between the substrate and the chip at the curing start temperature can be rapidly expanded and cured. Therefore, using the film of the present embodiment, low voids and excellent chip adhesion can be obtained. It is further inferred that by making the acrylic resin (A) contain hydroxyl groups, the chip adhesion of the adherend such as the chip and the substrate and the bottom filling material can be improved.

[0148] [Containing acrylic resin (A)]

[0149] The film of the present embodiment includes a propylene group-containing resin (A). The propylene group-containing resin (A) is not particularly limited as long as it includes a structural unit represented by formula (1) as a basic skeleton at a terminal in the molecule.

[0150]

[0151] In formula (1), -* represents an atomic bond, and is bonded to the main chain of the polymer.

[0152] The acryl-containing resin (A) contains a highly reactive acryl group at the end, so during the curing process, the acryl groups react with each other, and the maleimide group and the citraconimide group react with the acryl group. Therefore, the crosslinking density of the obtained cured product is increased, low voids are obtained, and further, the heat resistance (glass transition temperature) is also improved. In addition, since it has a polar group, the chip adhesion of the adherend such as a chip and a substrate to the bottom filling material is also improved.

[0153] The polymer serving as the main chain of the acrylic group-containing resin (A) is not particularly limited as long as it contains an alkenyl group and a hydroxyl group.

[0154] The alkenyl group is not particularly limited, and examples thereof include vinyl, (meth)allyl, propenyl, butenyl, and hexenyl. Among these, propenyl is preferred.

[0155] As polymer, there is no particular limitation, for example, bisphenol A, tetramethyl bisphenol A, diallyl bisphenol A, biphenol, bisphenol F, diallyl bisphenol F, triphenylmethane type phenol, tetraphenol, novolac type phenol, cresol novolac resin, phenol (biphenyl type phenol) containing biphenyl aralkyl skeleton, etc., polymer containing alkenyl in phenol ring. These polymers optionally have substituents. In addition, these polymers can be one or more suitable combinations of two or more.

[0156] Examples of such substituents include halogen atoms and linear, branched or cyclic hydrocarbon groups. The linear, branched or cyclic hydrocarbon groups preferably include alkenyl groups as substituents. The alkenyl groups are as described above.

[0157] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0158] The linear or branched hydrocarbon group is not particularly limited, and examples thereof include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, tert-pentyl, n-hexyl, isohexyl, sec-hexyl, and tert-hexyl.

[0159] The cyclic hydrocarbon group is not particularly limited, and examples thereof include aliphatic cyclic hydrocarbon groups and aromatic hydrocarbon groups. Examples of the aliphatic cyclic hydrocarbon group include monocyclic aliphatic hydrocarbon groups such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclodecyl, and cyclododecyl; bicyclo[2.2.2]octyl, tricyclo[5.2.1.0 2,6 ]decyl, tricyclic [3.3.1.1 3,7 ]decyl, tetracyclic [6.2.1.1 3,6 .0 2,7 ] polycyclic aliphatic hydrocarbon groups such as dodecyl and adamantyl. As the aromatic hydrocarbon group, for example, a group obtained by removing one hydrogen atom from an aromatic hydrocarbon ring such as benzene, biphenyl, fluorene, naphthalene, anthracene, and phenanthrene can be listed.

[0160] The acryl-containing resin (A) is not particularly limited. From the viewpoint of preventing voids caused by volatilization of the acryl-containing resin (A) during flip-chip mounting, the mass average molecular weight of the acryl-containing resin (A) is preferably 300 to 10,000, more preferably 400 to 7,000, and even more preferably 1,000 to 3,000 in terms of polystyrene conversion based on a gel permeation chromatography (GPC) method.

[0161] The propylene group-containing resin (A) preferably includes a resin represented by formula (2). When the film of the present embodiment includes such a propylene group-containing resin (A), excellent heat resistance can be obtained.

[0162]

[0163] In formula (2), W each independently represents a hydrocarbon group having 6 to 15 carbon atoms which may have a substituent. U each independently represents a hydrogen atom or an alkenyl group having 2 to 6 carbon atoms. 1 Represents the number of repetitions, whose average value is a real number between 1 and 20.

[0164] In formula (2), W each independently represents a hydrocarbon group having 6 to 15 carbon atoms which may have a substituent. The substituent in W preferably contains an aromatic ring, and in this case, the acrylic group-containing resin (A) is preferably represented by formula (3).

[0165] In addition, W in formula (2) is preferably an aromatic hydrocarbon group, and more preferably an aromatic hydrocarbon group having 10 to 15 carbon atoms. W is not particularly limited, and examples thereof include the following structures. These structures may be one or a combination of two or more as appropriate.

[0166]

[0167] Among these, from the viewpoint of heat resistance, W preferably contains an alkyl-type biphenyl skeleton.

[0168] In formula (2), the number of alkenyl groups in the molecule is preferably 20% or more of the total of U and the terminal propenyl groups. In formula (2), preferably 40% or more of the alkenyl groups in the molecule are propenyl groups, and more preferably 60% or more of the alkenyl groups in the molecule are propenyl groups. The upper limit is not particularly limited and is 100% or less. When the alkenyl groups in the molecule are within the above range, excellent curability can be obtained.

[0169] In formula (2), U other than the propenyl group independently represents a hydrogen atom or an alkenyl group having 2 to 6 carbon atoms. Examples of the alkenyl group having 2 to 6 carbon atoms include vinyl, (meth)allyl, butenyl, and hexenyl. As U other than the propenyl group, a hydrogen atom is preferred from the viewpoint of being able to appropriately control the curability.

[0170] In formula (2), n 1 represents the number of repetitions, whose average value is a real number between 1 and 20. 1 , from the viewpoint that curability can be appropriately controlled, the average value is preferably a real number of 1 to 10, and more preferably a real number of 1 to 6.

[0171] When W in formula (2) contains an aromatic ring as a substituent, the acrylic group-containing resin (A) is preferably represented by formula (3).

[0172]

[0173] In formula (3), Y each independently represents a hydrocarbon group having 1 to 6 carbon atoms. X each independently represents a hydrogen atom or an alkenyl group having 2 to 6 carbon atoms. 2 Represents the number of repetitions, whose average value is a real number between 1 and 20.

[0174] In formula (3), Y each independently represents a divalent hydrocarbon group having 1 to 6 carbon atoms. Y is a structure in which one of the hydrogen atoms in the divalent hydrocarbon group having 1 to 6 carbon atoms is replaced by a phenol ring containing an alkenyl group. Y is not particularly limited, but is preferably a divalent hydrocarbon group having 1 to 6 carbon atoms, which is linear, branched, or cyclic.

[0175] The straight-chain hydrocarbon group is not particularly limited, and examples thereof include methylene, ethylene, propylene, butylene, pentylene, and hexylene. The branched hydrocarbon group includes, for example, alkylmethylene groups such as -C(CH3)2-, -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and -C(CH2CH3)2-; and alkylethylene groups such as -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-.

[0176] The cyclic hydrocarbon group is not particularly limited, and examples thereof include a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, and a cyclohexylene group.

[0177] These hydrocarbon groups may be used alone or in combination of two or more.

[0178] Among these, Y is preferably a methylene group from the viewpoint of obtaining good compatibility with other resins such as a radical polymerizable resin or compound (B) described later.

[0179] In formula (3), the number of alkenyl groups in the molecule is preferably 20% or more of the total of X and the terminal acryl groups. In formula (3), preferably 40% or more of the alkenyl groups in the molecule are acryl groups, and more preferably 60% or more are acryl groups. The upper limit is not particularly limited, but is 100% or less. When the alkenyl groups in the molecule are within the above range, excellent curability can be obtained.

[0180] In formula (3), X other than the acrylic group independently represents a hydrogen atom or an alkenyl group having 2 to 6 carbon atoms. The alkenyl group having 2 to 6 carbon atoms is as described above. As U other than the acrylic group, a hydrogen atom is preferred from the viewpoint of being able to appropriately control the curability.

[0181] In formula (2), n2 represents the number of repetitions, whose average value is a real number between 1 and 20. 1 , from the viewpoint that curability can be appropriately controlled, the average value is preferably a real number of 1 to 10, and more preferably a real number of 1 to 6.

[0182] The method for producing the propylene group-containing resin (A) represented by the formula (2) or (3) is not particularly limited, and the resin can be produced by a known method.

[0183] As a manufacturing method, for example, a method using a phenolic resin as a raw material can be cited. As the phenolic resin, there is no particular limitation, and bisphenol A, tetramethylbisphenol A, diallyl bisphenol A, biphenol, bisphenol F, diallyl bisphenol F, triphenylmethane type phenol, tetraphenol, novolac type phenol, cresol novolac resin, phenol containing a biphenyl aralkyl skeleton (biphenyl type phenol), and phenol containing a triphenylmethane skeleton (triphenylmethane type phenol) can be cited.

[0184] In the production method, the hydroxyl groups in these phenolic resins are allylated to synthesize allyl ethers, and then the obtained allyl ether groups are subjected to rearrangement reaction to form propenyl ether groups to obtain the phenolic resin. In addition, the obtained allyl ether groups are subjected to Claisen rearrangement reaction to obtain allylated phenols, and then the phenolic resins can be obtained by subjecting the allyl groups to rearrangement reaction to form propenyl groups according to a known method.

[0185] As the propylene-containing resin (A), a propylene-containing resin having a structure represented by formula (25) and a propylene-containing resin having a structure represented by formula (26) are preferred. As such a propylene-containing resin (A), commercially available products can be used. For example, as a propylene-containing resin having a structure represented by formula (25), BPN01-S (trade name, mass average molecular weight: 1830) manufactured by Gunei Chemical Industry Co., Ltd. can be listed, and as a propylene-containing resin having a structure represented by formula (26), TPMP01 (trade name, mass average molecular weight: 2371) manufactured by Gunei Chemical Industry Co., Ltd. can be listed.

[0186]

[0187] In formula (25), n 11 It is a mixture of 1 to 10.

[0188]

[0189] In formula (26), n 12 It is a mixture of 1 to 10.

[0190] [Free radical polymerizable resin or compound (B)]

[0191] From the perspective of being able to obtain excellent insulation reliability and heat resistance, the film of this embodiment contains a radical polymerizable resin or compound (B) that is different from the acryl-containing resin (A) and contains at least one selected from the group consisting of a maleimide group and a citraconimide group in the molecule. The radical polymerizable resin or compound (B) is not particularly limited as long as it is reactive with the acryl-containing resin (A) together with the curing accelerator (C) described later. The radical polymerizable resin or compound (B) preferably does not react with the organic compound (H) having a fluxing function described later. These radical polymerizable resins or compounds (B) can be used alone or in combination of two or more.

[0192] The radical polymerizable resin or compound (B) preferably contains a maleimide group in the molecule in order to obtain excellent reactivity with the acrylic group-containing resin (A) and to obtain excellent insulation reliability and heat resistance.

[0193] The reason why the maleimide compound is preferred is still unclear, but the inventors of the present invention presume as follows. That is, the inventors of the present invention presume that the maleimide compound has a more excellent reactivity with the acrylic resin (A), thereby obtaining excellent curing properties, and the crosslinking density of the cured product is increased, thereby suppressing the unfilled portion of the bottom fill between the chip and the substrate and the bottom fill material, and obtaining low voids. In addition, as a result, more excellent insulation reliability and heat resistance are also obtained.

[0194] The radical polymerizable resin or compound (B) containing a maleimide group is not particularly limited as long as it contains one or more maleimide groups in the molecule. The radical polymerizable resin or compound (B) containing a maleimide group may be used alone or in combination of two or more.

[0195] For example, N-phenylmaleimide, N-hydroxyphenylmaleimide, bis(4-maleimidephenyl)methane, 4,4-diphenylmethanebismaleimide, bis(3,5-dimethyl-4-maleimidephenyl)methane, bis(3-ethyl-5-methyl-4-maleimidephenyl)methane, bis(3,5-diethyl-4-maleimidephenyl)methane, phenylmethanemaleimide, o-phenylenebismaleimide, m-phenylenebismaleimide, Phenylene bismaleimide, p-phenylene bismaleimide, p-phenylene biscitraconimide, 2,2-bis(4-(4-maleimidophenoxy)-phenyl)propane, 3,3-dimethyl-5,5-diethyl-4,4-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, 1,6-bismaleimide-(2,2,4-trimethyl)hexane, 4,4-diphenyl ether bismaleimide, 4,4 -Diphenylsulfone bismaleimide, 1,3-bis(3-maleimide phenoxy)benzene, 1,3-bis(4-maleimide phenoxy)benzene, polyphenylmethane maleimide, novolac type maleimide compounds, biphenyl aralkyl type maleimide compounds, 2,2-bis(4-(4-maleimide phenoxy)phenyl)propane, 1,2-bis(maleimide)ethane, 1,4-bis(maleimide)butane, 1,6-bis(maleimide) The maleimide compound represented by formula (4) is selected from the group consisting of maleimide (I)-hexane, N,N'-1,3-phenylenedimaleimide, N,N'-1,4-phenylenedimaleimide, N-phenylmaleimide, a maleimide compound represented by formula (4), a maleimide compound represented by formula (5), a maleimide compound represented by formula (6), a maleimide compound represented by formula (7), a maleimide compound represented by formula (8), and a maleimide compound represented by formula (9). The radical polymerizable resin or compound (B) containing a maleimide group may be contained in the film in the form of a prepolymer obtained by polymerizing a maleimide compound, or a prepolymer obtained by polymerizing a maleimide compound with other compounds such as an amine compound.

[0196] Among these, 2,2-bis[4-(4-maleimidephenoxy)phenyl]propane, 1,2-bis(maleimide)ethane, 1,4-bis(maleimide)butane, 1,6-bis(maleimide)hexane, N,N'-1,3-phenylene dimaleimide, N,N'-1,4-phenylene dimaleimide, N-phenylmaleimide, the maleimide compound represented by formula (4), the maleimide compound represented by formula (5), the maleimide compound represented by formula (6) are preferred from the viewpoint of solubility in organic solvents. The maleimide compound represented by formula (6) is preferably bis-(3-ethyl-5-methyl-4-maleimidephenyl)methane.

[0197]

[0198] In formula (4), R 1 Each independently represents a hydrogen atom or a methyl group, and is preferably a hydrogen atom from the viewpoint of more effectively and reliably exerting the effects of the present embodiment. 3 represents an integer from 1 to 10. 3 The upper limit value is preferably 7 from the viewpoint of solubility in organic solvents.

[0199]

[0200] In formula (5), n 4 represents an integer from 1 to 30. From the viewpoint of more effectively and reliably exerting the effects of the present embodiment, n 4 An integer of 7-30 is preferable, and an integer of 7-18 is more preferable.

[0201]

[0202] In formula (6), R 2 Each independently represents a hydrogen atom, a methyl group, or an ethyl group.

[0203] In formula (6), R 3 Each independently represents a hydrogen atom or a methyl group.

[0204]

[0205] In formula (7), R 4 Each independently represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a phenyl group, l each independently represents an integer of 1 to 3, and n 5 Indicates an integer from 1 to 10.

[0206] Examples of the alkyl group having 1 to 5 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, and neopentyl. The maleimide compound represented by formula (7) is preferred because it can reduce the elastic modulus of a cured product obtained by curing a thin film.

[0207]

[0208] In formula (8), R 5 and R 7 Each independently represents a hydrocarbon group having 8 or more atoms connected in a straight chain. 6 Each independently represents a substituted or unsubstituted cyclic hydrocarbon group having 4 to 10 atoms constituting the ring and optionally containing a hetero atom. 6 Indicates an integer from 1 to 10.

[0209] R 5 and R 7 All are hydrocarbon groups formed by connecting 8 or more atoms in a straight chain, for example, substituted or unsubstituted divalent hydrocarbon groups containing 8 or more carbon atoms. The substituted or unsubstituted divalent hydrocarbon group is not particularly limited, for example, substituted or unsubstituted straight-chain aliphatic hydrocarbon groups, substituted or unsubstituted branched aliphatic hydrocarbon groups, and substituted or unsubstituted cyclic aliphatic hydrocarbon groups can be listed. For example, octylene, nonamethylene, decamethylene, dodecamethylene, hexamethylene, and octadecamethylene can be listed.

[0210] R 6In the substituted or unsubstituted cyclic hydrocarbon group having 4 to 10 atoms constituting the ring and optionally containing heteroatoms, for example, a substituted or unsubstituted alicyclic group having 4 to 10 atoms constituting the ring; a substituted or unsubstituted aromatic group having 4 to 10 atoms constituting the ring; and a substituted or unsubstituted heterocyclic group having 4 to 10 atoms constituting the ring. It should be noted that the number of atoms constituting the ring is the number of atoms connected to form a ring, and does not include the number of atoms of the substituents of the side chain. As the group of the alicyclic part in the substituted or unsubstituted alicyclic group, for example, a divalent or higher valent cyclobutyl, cyclopentyl, cyclohexyl, cyclooctyl, and cyclodecyl group can be listed. In addition, when the substituent is an alkyl group, the alkyl group is not particularly limited, but an alkyl group having 1 to 10 carbon atoms is preferred, and an alkyl group having 3 to 10 carbon atoms is more preferred. Examples of the alkyl group having 1 to 10 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, neopentyl, n-hexyl, 1,1,2-trimethylpropyl (thexyl), n-heptyl, n-octyl, n-ethylhexyl, n-nonyl, and n-decyl. The alkyl group substituted with an alkyl group may be one or more.

[0211]

[0212] In formula (9), R 8 Each independently represents an alkylene group. 9 Each independently represents an alkylene group, a group represented by the formula (10), a group represented by the formula "-SO2-", a group represented by "-CO-", a group represented by the formula (11), an oxygen atom, or a single bond. 7 Indicates an integer from 1 to 10.

[0213] R 8 and R 9 The alkylene groups are as described above.

[0214]

[0215] In formula (10), Z is an alkylene group or a hydrocarbon group having 6 to 30 carbon atoms and containing an aromatic ring. 8 Indicates an integer from 0 to 5. n 8 It is preferably an integer of 1 to 3, and more preferably 1 or 2.

[0216] In Z, the alkylene group and the hydrocarbon group having 6 to 30 carbon atoms including an aromatic ring are as described above.

[0217]

[0218] As a free radical polymerizable resin or compound (B) containing a maleimide group, from the viewpoint of good solubility and flexibility in an organic solvent, a maleimide compound represented by formula (5) is preferred, more preferably comprising the maleimide compound represented by formula (5) and at least one maleimide compound selected from the group consisting of 2,2-bis(4-(4-maleimidephenoxy)phenyl)propane, a maleimide compound represented by formula (6), and a maleimide compound represented by formula (7), and further preferably comprising all of the maleimide compound represented by formula (5), 2,2-bis(4-(4-maleimidephenoxy)phenyl)propane, the maleimide compound represented by formula (6), and the maleimide compound represented by formula (7).

[0219] As described above, in order to suppress voids generated during thermocompression bonding of the chip and substrate to the underfill material in flip chip packaging, the film curing start temperature and the film melt viscosity at the thermocompression bonding temperature are important. In this regard, from the perspective of having a moderate melt viscosity at the temperature during thermal compression bonding and excellent curing properties, it is preferred to use both a propenyl resin (A) and a maleimide compound represented by formula (7) as the free radical polymerizable resin or compound (B) containing a maleimide group. It is more preferred to use both the propenyl resin (A) and the maleimide compound represented by formula (7) and at least one maleimide compound selected from the group consisting of 2,2-bis(4-(4-maleimidephenoxy)phenyl)propane, the maleimide compound represented by formula (5), and the maleimide compound represented by formula (6). It is further preferred to use all of the propenyl resin (A), the maleimide compound represented by formula (5), 2,2-bis(4-(4-maleimidephenoxy)phenyl)propane, the maleimide compound represented by formula (6), and the maleimide compound represented by formula (7). By including an propylene-containing resin (A) and such a free radical polymerizable resin or compound (B) containing a maleimide group, the film of this embodiment allows the molten resin composition between the substrate and the chip to spread more rapidly, solidify, and obtain low voids and excellent adhesion, which is therefore preferred.

[0220] The radical polymerizable resin or compound (B) containing a maleimide group may be a commercially available product, and as 2,2-bis(4-(4-maleimidephenoxy)phenyl)propane, for example, BMI-80 (trade name) manufactured by KI Chemical Industry Co., Ltd. may be cited. As the maleimide compound represented by formula (4), for example, BMI-2300 (trade name) manufactured by Yamato Chemical Industry Co., Ltd. may be cited. Examples of the maleimide compound represented by formula (5) include BMI-1000P manufactured by K.I. Chemical Industry Co., Ltd. (trade name, n4=14 (average) in formula (5)), BMI-650P manufactured by K.I. Chemical Industry Co., Ltd. (trade name, n4=9 (average) in formula (5)), BMI-250P manufactured by K.I. Chemical Industry Co., Ltd. (trade name, n4=3 to 8 (average) in formula (5)), and CUA-4 manufactured by K.I. Chemical Industry Co., Ltd. (trade name, n4=1 in formula (5)). Examples of the maleimide compound represented by formula (6) include BMI-70 (trade name) manufactured by KI Chemical Industry Co., Ltd. Examples of the maleimide compound represented by formula (7) include MIR-3000-70MT (trade name, R in formula (7)) manufactured by Nippon Kayaku Co., Ltd. 4 All are hydrogen atoms, n 5 is a mixture of 1 to 10). Examples of the maleimide compound represented by formula (8) include BMI-5000 (trade name) manufactured by Designer Molecules Inc. Examples of the maleimide compound represented by formula (9) include BMI-6000 (trade name) manufactured by Designer Molecules Inc.

[0221] The radical polymerizable resin or compound (B) containing a citraconimide group as a radical polymerizable group is not particularly limited as long as it is a resin or compound containing one or more citraconimide groups in the molecule. For example, o-phenylene bis-citraconimide, m-phenylene bis-citraconimide, p-phenylene bis-citraconimide, 4,4-diphenylmethane bis-citraconimide, 2,2-bis[4-(4-citraconimide phenoxy)phenyl]propane, bis(3,5-dimethyl-4-citraconimide phenyl)methane, bis(3-ethyl-5-methyl-4-citraconimide phenyl)methane, bis(3,5-diethyl-4-citraconimide phenyl)methane, 1,3-phenylenedimethylbis(citraconimide, N- -[3-bis(trimethylsilyl)amino-1-propyl]citraconimide, N-[3-bis(triethylsilyl)amino-1-propyl]citraconimide, N-[3-bis(triphenylsilyl)amino-1-propyl]citraconimide, N,N'-(m-phenylenedimethylene)biscitraconimide, and N-[3-(methylenesuccinimidylmethyl)benzyl]citraconimide. The resin or compound (B) containing a citraconimide group may be used alone or in combination of two or more.

[0222] In the film of the present embodiment, from the perspective of obtaining more excellent curability, low voids, and chip bonding, the ratio of the acryl group in the acryl-containing resin (A) to the polymerizable functional group in the radical polymerizable resin or compound (B) (acrylic group: polymerizable functional group) is preferably 1:1 to 1:7, more preferably 1:1.3 to 1:5, and further preferably 1:1.5 to 1:4. It should be noted that the polymerizable functional group in the radical polymerizable resin or compound (B) represents a maleimide group and / or a citraconimide group. In addition, in the present embodiment, the ratio (acrylic group: polymerizable functional group) is calculated using the amount of acryl groups in the acryl-containing resin (A) (hereinafter referred to as "acrylic group amount") and the amount of polymerizable functional groups in the radical polymerizable resin or compound (B) (hereinafter referred to as "polymerizable functional group amount"). The amount of propylene groups is calculated by dividing the amount of propylene-containing resin (A) by the functional group equivalent of the propylene-containing resin (A). The amount of polymerizable functional groups is calculated by dividing the amount of radical polymerizable resin or compound (B) by the functional group equivalent of the radical polymerizable resin or compound (B). When there are multiple propylene-containing resins (A), the amount of propylene groups of each resin is calculated by the above-mentioned calculation method, and these amounts are added together to obtain the value of the propylene group amount. Similarly, when there are multiple radical polymerizable resins or compounds (B), the amount of polymerizable functional groups of each resin or compound is calculated by the above-mentioned calculation method, and these amounts are added together to obtain the value of the polymerizable functional groups.

[0223] In the film of the present embodiment, when the maleimide compound represented by formula (5) is included as the free radical polymerizable resin or compound (B) containing a maleimide group, there is no particular limitation. From the perspective of being able to obtain good solubility in organic solvents and good flexibility, the maleimide compound represented by formula (5) is preferably included in an amount of 5 to 60 parts by mass, and more preferably 25 to 55 parts by mass, relative to a total of 100 parts by mass of the acrylic resin (A) and the free radical polymerizable resin or compound (B) containing a maleimide group.

[0224] In the film of the present embodiment, the free radical polymerizable resin or compound (B) containing a maleimide group includes a maleimide compound represented by formula (5), 2,2-bis(4-(4-maleimidephenoxy)phenyl)propane, a maleimide compound represented by formula (6), and a maleimide compound represented by formula (7), but is not particularly limited. From the perspective of being able to obtain better curability, low voids, and better chip bonding properties, the free radical polymerizable resin or compound (B) containing a maleimide group is preferably selected from the group consisting of the acrylic resin (A) and the maleimide group-containing free radical polymerizable resin or compound (B). The total amount of the polymerizable resin or compound (B) is 100 parts by mass, preferably 10 to 35 parts by mass of the acrylic resin (A), 25 to 55 parts by mass of the maleimide compound represented by formula (5), 2 to 25 parts by mass of 2,2-bis(4-(4-maleimidephenoxy)phenyl)propane, 2 to 25 parts by mass of the maleimide compound represented by formula (6), and 15 to 40 parts by mass of the maleimide compound represented by formula (7).

[0225] 〔Curing accelerator (C)〕

[0226] From the aspect of being able to appropriately adjust the curing speed and obtain excellent low void properties, the film of this embodiment contains a curing accelerator (C). The curing accelerator (C) is not particularly limited as long as it is a compound that can promote the curing of the propylene-containing resin (A) and the free radical polymerizable resin or compound (B). The curing accelerator (C) can be used alone or in combination of two or more.

[0227] The curing accelerator (C) is not particularly limited, and examples thereof include a thermal radical polymerization initiator (D), an imidazole compound (E), and tertiary amines such as triethylamine and tributylamine. Among these, from the aspect of being able to obtain a good curing speed, it is preferred to include at least one selected from the group consisting of a thermal radical polymerization initiator (D) and an imidazole compound (E), and it is more preferred to include both a thermal radical polymerization initiator (D) and an imidazole compound (E).

[0228] In the present embodiment, the content of the curing accelerator (C) is not particularly limited. From the perspective of being able to obtain a good curing speed, it is preferably contained in an amount of 0.05 to 10 parts by mass, and more preferably 0.05 to 8 parts by mass, relative to 100 parts by mass of the total of the propylene-based resin (A) and the free radical polymerizable resin or compound (B).

[0229] (Thermal radical polymerization initiator (D))

[0230] The thermal radical polymerization initiator (D) is not particularly limited as long as it is a compound that releases an active substance (radical) that can polymerize the acryl group in the acryl-containing resin (A) and the polymerizable functional group of the radical polymerizable resin or compound (B) due to heat, and a known thermal radical polymerization initiator can be used. The thermal radical polymerization initiator (D) can be used alone or in combination of two or more.

[0231] In the present embodiment, the 10-hour half-life temperature of the thermal radical polymerization initiator (D) is not particularly limited, but is preferably 100° C. or higher, and more preferably 110° C. or higher from the viewpoint of manufacturability. In the present embodiment, in order to achieve a high temperature for the solvent removal step during production, the thermal radical polymerization initiator (D) preferably has a 10-hour half-life temperature that satisfies the aforementioned range.

[0232] Examples of the thermal radical polymerization initiator (D) include diisopropylbenzene peroxide, di(2-tert-butylperoxyisopropyl)benzene, 1,1,3,3-tetramethylbutyl hydroperoxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)3-hexyne, benzoyl peroxide, di-tert-butyl peroxide, methyl ethyl ketone peroxide, and cyclohexanone peroxide; peroxyketals such as 1,1-di(tert-butylperoxy)cyclohexane and 2,2-di(4,4-di(tert-butylperoxy)cyclohexyl)propane; hydroperoxides such as tert-butyl hydroperoxide, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, cumene hydroperoxide, and tert-butyl hydroperoxide; di(2-tert-butylperoxyisopropyl)benzene, 2,5-dimethyl-2,5-di(tert-butylperoxy)hexane; , tert-butylcumyl peroxide, di-tert-hexyl peroxide, 2,5-dimethyl-2,5-di(tert-butylperoxy)3-hexyne, and di-tert-butyl peroxide; diacyl peroxides such as dibenzoyl peroxide and di(4-methylbenzoyl)peroxide; peroxydicarbonates such as di-n-propyl peroxydicarbonate and diisopropyl peroxydicarbonate; organic peroxides such as peroxyesters of 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, tert-hexyl peroxybenzoate, tert-butyl peroxybenzoate, and tert-butyl peroxy-2-ethylhexanoate; azo compounds such as 2,2'-azobisbutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), and 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile);

[0233] In the present embodiment, from the perspective of obtaining a good curing speed, an organic peroxide is preferred, and a peroxyester, a peroxyketal, a dialkyl peroxide, and an organic peroxide containing a hydroperoxide skeleton are more preferred. Diisopropylbenzene peroxide, di(2-tert-butylperoxyisopropyl)benzene, 1,1,3,3-tetramethylbutyl hydroperoxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)3-hexyne, and tert-butyl hydroperoxide are further preferred from the perspective of having an appropriate curing speed and having an appropriate manufacturability without being deactivated during the production of a thin film or the like.

[0234] In the film of the present embodiment, the content of the thermal radical polymerization initiator (D) is not particularly limited. From the perspective of obtaining a good curing speed, it is preferably contained in an amount of 0.05 to 10 parts by mass, and more preferably 0.05 to 8 parts by mass, relative to 100 parts by mass of the total of the propylene-based resin (A) and the radical polymerizable resin or compound (B).

[0235] (Imidazole compound (E))

[0236] The imidazole compound (E) is not particularly limited as long as it can accelerate the curing of the acrylic group-containing resin (A) and the radical polymerizable resin or compound (B), and a known imidazole compound can be used. The imidazole compound (E) can be used alone or in combination of two or more.

[0237] Examples of the imidazole compound (E) include 2-ethyl-4-methylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 2,4,5-triphenylimidazole, tertiary amines such as triethylamine and tributylamine, and derivatives thereof. Among them, 2-ethyl-4-methylimidazole is preferred because it is easy to adjust the curing rate.

[0238] In the film of the present embodiment, the content of the imidazole compound (E) is not particularly limited. From the perspective of easy adjustment of the curing speed, it is preferably contained in an amount of 0.05 to 10 parts by mass, and more preferably 0.05 to 8 parts by mass, relative to 100 parts by mass of the total of the propylene-based resin (A) and the free radical polymerizable resin or compound (B).

[0239] [Thermosetting compound (F)]

[0240] The film of the present embodiment is not particularly limited, and preferably further comprises a thermosetting compound (F) other than the propylene-containing resin (A) and the radical polymerizable resin or compound (B) from the aspect of easy adjustment of the curing speed. As the thermosetting compound (F), any known compound can be used as long as it is a compound that is reactive with the propylene-containing resin (A) and the radical polymerizable resin or compound (B), and it is not particularly limited. As the thermosetting compound (F), it is preferred that it does not show reactivity with the organic compound (H) having a fluxing function described later.

[0241] The molecular weight of the thermosetting compound (F) is not particularly limited, but is preferably 400 or more from the viewpoint of preventing voids caused by volatilization of the thermosetting compound (F) during flip chip mounting. On the other hand, from the viewpoint of obtaining more sufficient fluxing activity, the molecular weight of the thermosetting compound (F) is preferably 10,000 or less.

[0242] Such a thermosetting compound (F) is not particularly limited, and examples thereof include compounds containing alkenyl groups, compounds containing (meth)acryloyl groups, and benzoxazine compounds. Among the thermosetting compounds (F), benzoxazine compounds are preferably included from the perspective of obtaining excellent flame retardancy, heat resistance, adhesion, and solubility in organic solvents. These thermosetting compounds (F) can be used alone or in combination of two or more.

[0243] The compound containing an alkenyl group is not particularly limited as long as it contains one or more carbon-carbon double bonds in the molecule, and examples thereof include compounds containing a vinyl group and compounds containing a (meth)allyl group.

[0244] Examples of the compound containing a vinyl group include divinylbenzene, divinylnaphthalene, styrene, and styrene derivatives. These compounds containing a vinyl group may be used alone or in combination of two or more.

[0245] As a compound containing a (meth)allyl group, as long as it is a compound containing more than one (meth)allyl group in the molecule, it is not particularly limited. For example, tri(meth)allyl cyanurate, tri(meth)allyl isocyanurate, tri(meth)allyl trimellitate, tetra(meth)allyl pyromellitate, pentaerythritol tri(meth)allyl ether, 2,2'-di(meth)allyl bisphenol A, (meth)allyl phenol novolac, and biphenylene type (meth)allyl phenol. These compounds containing (meth)allyl groups can be used in one or two or more mixtures.

[0246] As a compound containing a (meth)acryloyl group, there is no particular limitation as long as it is a compound containing one or more (meth)acryloyl groups in the molecule. As a compound containing a (meth)acryloyl group, for example, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, lauryl (meth)acrylate, polyethylene glycol (meth)acrylate, polyethylene glycol (meth)acrylate monomethyl ether, phenyl ethyl (meth)acrylate, isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, butanediol di(meth)acrylate, hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, nonanediol di(meth)acrylate, glycol di(meth)acrylate, diethylene di(meth)acrylate, polyethylene glycol di(meth)acrylate, tri(meth)acryloyloxyethyl isocyanurate, Polypropylene glycol di(meth)acrylate, adipic acid epoxy di(meth)acrylate, bisphenol ethylene oxide di(meth)acrylate, hydrogenated bisphenol ethylene oxide (meth)acrylate, bisphenol di(meth)acrylate, ε-caprolactone-modified hydroxypivalic acid neopentyl glycol di(meth)acrylate, ε-caprolactone-modified dipentaerythritol hexa(meth)acrylate, ε-caprolactone-modified dipentaerythritol poly(meth)acrylate, dipentaerythritol poly(meth)acrylate, trimethylolpropane tri(meth)acrylate, triethylolpropane tri(meth)acrylate, and ethylene oxide adducts thereof, pentaerythritol tri(meth)acrylate, and ethylene oxide adducts thereof, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and ethylene oxide adducts thereof. For example, hydroquinone and methyl ether hydroquinone-based polymerization inhibitors may be suitably used as needed. These (meth)acryloyl group-containing compounds may be used alone or in combination of two or more.

[0247] As a benzoxazine compound, it is not particularly limited as long as it has an oxazine ring as a basic skeleton. In the present embodiment, the benzoxazine compound also includes compounds containing a polycyclic oxazine skeleton such as naphthoxazine compounds. The benzoxazine compound does not produce volatile by-products due to heating, and the benzoxazine ring undergoes ring-opening polymerization to properly cure. The cured product has excellent heat resistance, water resistance, and flame retardancy. In addition, the benzoxazine compound generates phenolic hydroxyl groups and tertiary amino groups as polar groups during ring-opening polymerization, so high chip adhesion and substrate adhesion can be expected. The benzoxazine compound can be used alone or in combination of two or more.

[0248] The benzoxazine compound preferably includes at least one selected from the group consisting of a compound represented by formula (12), a compound represented by formula (13), a compound represented by formula (14), and a compound represented by formula (15). It should be noted that in this embodiment, the benzoxazine compound may include an oligomer generated by polymerization of a monomer.

[0249]

[0250] In formula (12), R 10 Each independently represents an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group. 11 represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, a cycloalkyl group, or a monovalent to tetravalent organic group represented by the general formulae (a) to (t). 9 Indicates an integer from 1 to 4.

[0251] For R 10 and R 11 All of them are, as an aryl group, an aryl group having 6 to 18 carbon atoms is preferred. Examples of such aryl groups include phenyl, naphthyl, indenyl, biphenyl, and anthracenyl. Among them, phenyl is more preferred. These aryl groups have a lower alkyl group having 1 to 4 carbon atoms in the range of 1 or more, preferably 1 to 3. Examples of such aryl groups containing a lower alkyl group include tolyl, xylyl, and methylnaphthyl.

[0252] For R 10 and R 11 In all cases, the aralkyl group is preferably a benzyl group or a phenethyl group. These have one or more, preferably 1 to 3, lower alkyl groups having 1 to 4 carbon atoms on the phenyl group.

[0253] For R 10 and R 11 As the alkenyl group, for example, vinyl, (meth)allyl, propenyl, butenyl, and hexenyl can be cited. Among these, vinyl, allyl, and propenyl are preferred, and allyl is more preferred.

[0254] For R 10 and R 11 As the alkyl group, an alkyl group having 1 to 20 carbon atoms is preferred, and an alkyl group having 1 to 10 carbon atoms is more preferred. The alkyl group having 3 or more carbon atoms may be linear or branched. For example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, neopentyl, n-hexyl, 1,1,2-trimethylpropyl, n-heptyl, n-octyl, n-ethylhexyl, n-nonyl, and n-decyl may be mentioned.

[0255] For R 10 and R 11In all cases, examples of the cycloalkyl group include cyclopentyl, cyclohexyl, and cycloheptyl, and cyclohexyl is preferred.

[0256]

[0257] In formula (13), R 12 Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group. 13 represents an aryl group, an aralkyl group, an alkenyl group, an alkyl group, a cycloalkyl group, or a monovalent to tetravalent organic group represented by the general formulae (a) to (t). 10 Indicates an integer from 1 to 4.

[0258] For R 12 and R 13 The same are as described above with respect to the aryl group, aralkyl group, alkenyl group, alkyl group, and cycloalkyl group.

[0259]

[0260] In formula (14), R 14 It represents an alkyl group, a cycloalkyl group, or a phenyl group which may have a substituent.

[0261] For R 14 The alkyl and cycloalkyl groups are as described above.

[0262] Examples of the phenyl group which may have a substituent include unsubstituted phenyl; monosubstituted phenyl groups such as 4-methylphenyl, 3-methoxyphenyl, 4-cyclohexylphenyl, and 4-methoxyphenyl; disubstituted phenyl groups such as 3,5-dimethylphenyl, 3,4-dimethylphenyl, and 3,5-dimethoxyphenyl; trisubstituted phenyl groups such as 3,4,5-trimethylphenyl; and 2-naphthyl groups which may have a substituent such as 2-naphthyl, 3-methyl-2-naphthyl, and 4-methyl-2-naphthyl.

[0263]

[0264] In formula (15), R 15 It represents an alkyl group, a cycloalkyl group, or a phenyl group which may have a substituent.

[0265] For R 15 The alkyl, cycloalkyl or phenyl group which may have a substituent is as described above.

[0266]

[0267]

[0268] In the general formulas (a) to (t), R a represents an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group. brepresents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group.

[0269] For R a and R b The same are as described above with respect to the aryl group, aralkyl group, alkenyl group, alkyl group, and cycloalkyl group.

[0270] The benzoxazine compound preferably contains at least one selected from the group consisting of compounds represented by formula (23) and compounds represented by formula (24) from the viewpoint of solvent solubility, since excellent flame retardancy and heat resistance can be obtained.

[0271]

[0272] In formula (23), R 16 Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group. o each independently represents an integer of 1 to 4. 17 Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group. Each independently represents an integer of 1 to 4. 1 It represents an alkylene group, a group represented by the formula (10), a group represented by the formula "-SO2-", a group represented by "-CO-", an oxygen atom, or a single bond.

[0273] For R 16 and R 17 The same are as described above with respect to the aryl group, aralkyl group, alkenyl group, alkyl group, and cycloalkyl group.

[0274] As T 1 The alkylene group in the embodiment is preferably a linear or branched alkylene group. Examples of the linear alkylene group include methylene, ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, and octadecylene. Examples of the branched alkylene group include -C(CH3)2-, -CH(CH3)-, -CH(CH2CH3)-, -C(CH3)(CH2CH3)-, -C(CH3)(CH2CH2CH3)-, and alkylmethylene groups of -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-; and alkylethylene groups of -CH(CH3)CH2-, -CH(CH3)CH(CH3)-, -C(CH3)2CH2-, -CH(CH2CH3)CH2-, and -C(CH2CH3)2-CH2-.

[0275]

[0276] In formula (24), R 18Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group. Each independently represents an integer of 1 to 3. 19 Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group. Each independently represents an integer of 1 to 5. 2 It represents an alkylene group, a group represented by the formula (10), a group represented by the formula "-SO2-", a group represented by "-CO-", an oxygen atom, or a single bond.

[0277] For R 18 and R 19 All are as described above with respect to aryl, aralkyl, alkenyl, alkyl, and cycloalkyl. 2 The alkylene group is as mentioned above.

[0278]

[0279] In formula (10), Z is an alkylene group or a hydrocarbon group having 6 to 30 carbon atoms and containing an aromatic ring. 8 Indicates an integer from 0 to 5. n 8 It is preferably an integer of 1 to 3, and more preferably 1 or 2.

[0280] The alkylene group in Z is as described above.

[0281] Examples of the hydrocarbon group having 6 to 30 carbon atoms and containing an aromatic ring include divalent groups obtained by removing two hydrogen atoms from the nucleus of aromatic compounds such as benzene, biphenyl, naphthalene, anthracene, fluorene, phenanthrene, indacene, terphenyl, acenaphthylene, and phenalene.

[0282] As the benzoxazine compound, a commercially available compound can be used, for example, Pd-type benzoxazine (manufactured by Shikoku Chemicals, Ltd., 3,3'-(methylene-1,4-diphenylene)bis(3,4-dihydro-2H-1,3-benzoxazine), hydroxyl equivalent: 217, molecular weight: 434) and Fa-type benzoxazine (manufactured by Shikoku Chemicals, Ltd., 2,2-bis(3,4-dihydro-2H-3-phenyl-1,3-benzoxazinyl)methane, hydroxyl equivalent: 217, molecular weight: 434) can be cited.

[0283] These benzoxazine compounds may be used alone or in combination of two or more.

[0284] When the film of the present embodiment contains a thermosetting compound (F), the content of the thermosetting compound (F) is not particularly limited. From the perspective of having good chip adhesion and flexibility, it is preferably 1 to 100 parts by mass, more preferably 5 to 80 parts by mass, and even more preferably 10 to 60 parts by mass, relative to 100 parts by mass of the total of the propylene-based resin (A) and the free radical polymerizable resin or compound (B).

[0285] [Inorganic filler (G)]

[0286] In order to improve flame retardancy, improve thermal conductivity, and reduce thermal expansion coefficient, the film of this embodiment preferably further contains an inorganic filler (G). By using an inorganic filler, the flame retardancy and thermal conductivity of the film can be improved, and the thermal expansion coefficient can be reduced.

[0287] The average particle size of the inorganic filler (G) is not particularly limited. When the film of the present embodiment is used as a pre-bottom filling material, it is preferably less than 3 μm, and more preferably less than 1 μm, from the viewpoint of narrowing the spacing of the electrodes arranged on the chip and the narrowing of the gaps between the electrodes. The lower limit of its average particle size is not particularly limited, for example, it is 10 nm. It should be noted that, in the present embodiment, the "average particle size" of the inorganic filler (G) refers to the median particle size of the inorganic filler (G). The median particle size here refers to the particle size in which the volume of the particles on the side with a larger particle size and the volume of the particles on the side with a smaller particle size account for approximately 50% of the total powder when the particle size distribution of the powder is divided into two parts based on a certain particle size. The average particle size (median particle size) of the inorganic filler (G) is measured by a wet laser diffraction and scattering method.

[0288] The inorganic filler (G) is not particularly limited, and examples thereof include silica such as natural silica, fused silica, amorphous silica, and hollow silica; aluminum compounds such as boehmite, aluminum hydroxide, aluminum oxide, and aluminum nitride; magnesium compounds such as magnesium oxide and magnesium hydroxide; calcium compounds such as calcium carbonate and calcium sulfate; molybdenum compounds such as molybdenum oxide and zinc molybdate; boron nitride; barium sulfate; talc such as natural talc and calcined talc; mica; glasses such as short fiber glass, spherical glass, and fine powder glass (e.g., E glass, T glass, D glass). In addition, when imparting conductivity or anisotropic conductivity to the film of this embodiment, as the inorganic filler (G), for example, metal particles of gold, silver, nickel, copper, tin alloy, and palladium can be used.

[0289] Among these, from the viewpoint of improving the flame retardancy and reducing the coefficient of thermal expansion of the film of the present embodiment, the inorganic filler (G) preferably comprises at least one selected from the group consisting of silica, aluminum hydroxide, alumina, boehmite, boron nitride, aluminum nitride, magnesium oxide, and magnesium hydroxide, more preferably silica, alumina, and boron nitride, among which silica is further preferred. As silicon dioxide, for example, there can be listed SFP-120MC (trade name) and SFP-130MC (trade name) manufactured by Denka Co., Ltd., 0.3μmSX-CM1 (trade name), 0.3μmSX-EM1 (trade name), 0.3μmSV-EM1 (trade name), SC1050-MLQ (trade name), SC2050-MNU (trade name), SC2050-MTX (trade name), 2.2μmSC6103-SQ (trade name), SE2053-SQ (trade name), Y50SZ-AM1 (trade name), YA050C-MJE (trade name), YA050C-MJF (trade name), and YA050C-MJA (trade name) manufactured by ADMATECHS CO., LTD.

[0290] These inorganic fillers (G) can be used alone or in combination of two or more.

[0291] The inorganic filler (G) may be one surface-treated with a silane coupling agent.

[0292] The silane coupling agent is not particularly limited as long as it is a silane coupling agent generally used for surface treatment of inorganic substances. For example, vinyl silane-based silane coupling agents such as vinyl trimethoxysilane and γ-methacryloxypropyl trimethoxysilane; phenyl amino silane-based silane coupling agents such as N-phenyl-3-aminopropyl trimethoxysilane; phenyl silane-based silane coupling agents such as trimethoxyphenyl silane; and imidazole silane-based silane coupling agents can be listed. These silane coupling agents can be used alone or in combination of two or more.

[0293] When the film of the present embodiment includes an inorganic filler (G), the content of the inorganic filler (G) is not particularly limited. From the viewpoint of improving the flame retardancy of the film, reducing the coefficient of thermal expansion, and ensuring the fluidity during the bonding of the pre-applied bottom filler, the content is preferably 500 parts by mass or less, more preferably 300 parts by mass or less, relative to 100 parts by mass of the total of the acrylic resin (A) and the radical polymerizable resin or compound (B). In addition, the content is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, and further preferably 50 parts by mass or more.

[0294] [Organic compound with fluxing function (H)]

[0295] In order to exhibit fluxing activity in flip chip installation, the film of the present embodiment preferably further comprises an organic compound (H) having a fluxing function. The organic compound (H) having a fluxing function is not particularly limited as long as it is an organic compound containing one or more acidic sites in the molecule. As the acidic site, for example, a phosphate group, a phenolic hydroxyl group, a carboxyl group, and a sulfonic acid group are preferred. From the viewpoint of more effectively preventing the migration and corrosion of metals such as solder and copper constituting the joint in a semiconductor device using the film of the present embodiment as a pre-bottom filling material, a phenolic hydroxyl group or a carboxyl group is more preferred. The organic compound (H) having a fluxing function can be used alone or in a suitable mixture of two or more.

[0296] The organic compound (H) having a fluxing function is not particularly limited, but the acid dissociation constant pKa is preferably 3.8 to 15.0 to sufficiently remove the oxide film at the joint, and is more preferably 4.0 to 14.0 to achieve a balance between the storage stability of the varnish and the resin laminate and the fluxing activity.

[0297] The organic compound (H) having a fluxing function in the thin film of the present embodiment is not particularly limited, but from the viewpoint of preventing volatilization before the fluxing activity is exhibited in flip chip mounting, that is, preventing the organic compound (H) having a fluxing function from volatilizing before the oxide film of the joint is removed, the molecular weight is preferably 200 or more, more preferably 250 or more. In order to have mobility as an acid and obtain sufficient fluxing activity, the molecular weight is preferably 8000 or less, more preferably 1000 or less, and further preferably 500 or less.

[0298] The organic compound (H) having a fluxing function is not particularly limited, and examples thereof include abietic acid, neoabietic acid, dehydroabietic acid, pimaric acid, isopimaric acid, palustric acid, diphenolic acid, dihydroabietic acid, tetrahydroabietic acid, abietic acid-modified resins such as rosin-modified maleic acid resin, N,N'-bis(salicylidene)-1,2-propylenediamine, N,N'-bis(salicylidene)-1,3-propylenediamine, and reduced phenolphthalein. These organic compounds (H) having a fluxing function are preferred from the viewpoint of solvent solubility and storage stability.

[0299] Among these, decahydroabietic acid, diphenolic acid, dihydroabietic acid, tetrahydroabietic acid, rosin-modified maleic acid resin and other rosin-modified resins, N,N'-bis(salicylidene)-1,2-propylenediamine, and N,N'-bis(salicylidene)-1,3-propylenediamine are more preferred from the viewpoint of preventing deactivation caused by the acrylic group-containing resin (A) and the radical polymerizable resin or compound (B). Decahydroabietic acid, dihydroabietic acid, rosin-modified maleic acid resin and other rosin-modified resins, N,N'-bis(salicylidene)-1,2-propylenediamine, and N,N'-bis(salicylidene)-1,3-propylenediamine are relatively low in reactivity and thus hardly cause reaction with the acrylic group-containing resin (A) and the radical polymerizable resin or compound (B), and are more preferred from the viewpoint of maintaining flux activity sufficient to remove oxide films.

[0300] As the organic compound (H) having a fluxing function, commercially available compounds can be used, for example, MALKYD No32 (manufactured by Arakawa Chemical Industries, Ltd., (trade name), acid value: 140 or less), MALKYD No31 (manufactured by Arakawa Chemical Industries, Ltd., (trade name) acid value: 200 or less), and MALKYD No33 (manufactured by Arakawa Chemical Industries, Ltd., (trade name) acid value: 290 to 320).

[0301] When the film of the present embodiment contains an organic compound (H) having a fluxing function, the content of the organic compound (H) having a fluxing function is not particularly limited. From the viewpoint of taking into account both the fluxing activity of the film and flexibility which is one of the important characteristics when forming a laminate and using it, the content is preferably 5 to 80 parts by mass, more preferably 5 to 60 parts by mass, and even more preferably 20 to 50 parts by mass, relative to 100 parts by mass of the total of the propylene-based resin (A) and the free radical polymerizable resin or compound (B).

[0302] [Other ingredients]

[0303] The film of this embodiment may contain one or more other components in addition to the acrylic resin (A), free radical polymerizable resin or compound (B), thermal free radical polymerization initiator (D), curing accelerator (C) such as imidazole compound (E), thermosetting compound (F), inorganic filler (G), and organic compound (H) having fluxing function.

[0304] As other components, it is not particularly limited, for example, flexibility imparting components can be listed.Flexibility imparting components are not particularly limited as long as they can impart flexibility to the layer comprising film. For example, thermoplastic macromolecular compounds such as polyimide, polyamide-imide, polystyrene, polyolefin, styrene-butadiene rubber (SBR), isoprene rubber (IR), butadiene rubber (BR), (meth) acrylonitrile-butadiene rubber (NBR), polyurethane, polypropylene, (meth) acrylic oligomers, (meth) acrylic polymers, and silicone resins can be listed except containing acrylic resin (A), free radical polymerizable resin or compound (B), thermosetting compound (F) and organic compound (H) with fluxing function.These flexibility imparting components can be used alone as one or more than two kinds are suitably mixed and used.

[0305] In order to improve the adhesion of the interface between the resin and the inorganic filler material and to improve the moisture absorption and heat resistance, the film of this embodiment may also contain a silane coupling agent as another component. As the silane coupling agent, for example, vinyl silane-based silane coupling agents such as vinyl trimethoxy silane and γ-methacryloxypropyl trimethoxy silane; phenyl amino silane-based silane coupling agents such as N-phenyl-3-aminopropyl trimethoxy silane; phenyl silane-based silane coupling agents such as trimethoxyphenyl silane; imidazole silane-based silane coupling agents. These silane coupling agents can be used alone or in combination of two or more.

[0306] When a silane coupling agent is used, its content is not particularly limited, but is preferably 0.05 to 20 parts by mass relative to 100 parts by mass of the total of the acrylic resin (A) and the radical polymerizable resin or compound (B), from the viewpoint of improving moisture absorption and heat resistance and reducing the amount of volatilization during flip chip mounting.

[0307] For the purpose of improving the manufacturability of laminated body and the dispersibility of filler, the film of the present embodiment may also include a wetting dispersant as other components. As a wetting dispersant, it is not particularly limited as long as it is a wetting dispersant used in common coatings, etc. For example, Disperbyk (registered trademark) -110 (trade name), Disperbyk-111 (trade name), Disperbyk-180 (trade name), Disperbyk-161 (trade name), BYK-W996 (trade name), BYK-W9010 (trade name) and BYK-W903 (trade name) made by BYK Japan KK can be listed. These wetting dispersants can be used alone as one or more than two kinds can be suitably mixed and used.

[0308] When a wetting dispersant is used, its content is not particularly limited, but is preferably 0.1 to 5 parts by mass, more preferably 0.5 to 3 parts by mass, relative to 100 parts by mass of the inorganic filler (G), from the viewpoint of improving the manufacturability of the laminate. It should be noted that when two or more wetting dispersants are used in combination, their total amount preferably satisfies the above ratio.

[0309] As other components, the film of the present embodiment may contain various additives for various purposes within the range that does not impair the desired properties. As additives, for example, ultraviolet absorbers, antioxidants, photopolymerization initiators, fluorescent whitening agents, photosensitizers, dyes, pigments, thickeners, lubricants, defoamers, leveling agents, glossing agents, flame retardants, and ion scavengers can be listed. As photopolymerization initiators, there are no particular limitations, for example, alkylphenone (Alkylphenone)-based photopolymerization initiators; acylphosphine oxide-based photopolymerization initiators; ditanocenes-based photopolymerization initiators can be listed. These additives can be used alone or in combination of two or more.

[0310] In the film of the present embodiment, the content of other additives is not particularly limited, but is usually 0.01 to 10 parts by mass of each based on 100 parts by mass of the total of the acrylic group-containing resin (A) and the radical polymerizable resin or compound (B).

[0311] 〔film〕

[0312] The film of this embodiment has excellent curing properties, low voids and excellent chip bonding properties. In addition, by coating the film of this embodiment on a supporting substrate, a laminated body including a layer of a film having low voids and excellent chip bonding properties can be provided. When the film of this embodiment is used as a pre-applied bottom filling material used in the form of a laminated body, in addition to the low voids and excellent chip bonding properties, the fluxing activity, bonding properties, and insulation reliability are also excellent. In this way, the film of this embodiment has various excellent characteristics, and in particular, it can satisfy the curing properties, low voids, and chip bonding properties at a high level, and is therefore more useful as a pre-applied bottom filling material.

[0313] The film of the present embodiment is preferably in a semi-cured state (B stage) from the aspect of being suitable for use as a pre-bottom filling material. By making the film in a semi-cured state, excellent low voids and chip adhesion can be obtained. In the present embodiment, the semi-cured state (B stage) refers to a state in which the components contained in the film do not actively start to react (curing), but the film is in a dry state, that is, the film is heated to evaporate the solvent to a state where there is no adhesion, and also includes a state in which the solvent is only evaporated without curing even without heating. In the present embodiment, the minimum melt viscosity of the semi-cured state (B stage) is generally less than 30,000 Pa·s from the aspect of being suitable for use as a pre-bottom filling material. It should be noted that in the present embodiment, the minimum melt viscosity can be measured by the method described in the examples.

[0314] The film of the present embodiment is prepared by appropriately mixing a curing accelerator (C) such as an propylene resin (A), a free radical polymerizable resin or compound (B), a thermal free radical polymerization initiator (D) and an imidazole compound (E), a thermosetting compound (F) as required, an inorganic filler (G), an organic compound (H) having a fluxing function, and other components. As needed, the varnish formed by dissolving or dispersing these components in an organic solvent can be used, and the varnish can be applied to a supporting substrate and dried to obtain it. For a specific manufacturing method, reference can be made to the manufacturing method and embodiments of the laminate described later. The film of the present embodiment can be peeled off from the supporting substrate after drying and used, or it can be used together with the supporting substrate.

[0315] The organic solvent is not particularly limited as long as it can dissolve or disperse the aforementioned components and does not impair the desired effect of the film of the present embodiment. Examples of the organic solvent include alcohols such as methanol, ethanol, and propanol; ketones such as acetone, methyl ethyl ketone (hereinafter, sometimes abbreviated as "MEK"), and methyl isobutyl ketone; amides such as dimethylacetamide and dimethylformamide; and aromatic hydrocarbons such as toluene and xylene. These organic solvents can be used alone or in combination of two or more.

[0316] The supporting substrate can use a known supporting substrate, which is not particularly limited, and is preferably a resin film. As the supporting substrate, it is not particularly limited, and a resin film can be used. As the material of the resin film, for example, a film of at least one resin selected from the group consisting of polyesters such as polyvinyl chloride, polyvinylidene chloride, polybutene, polybutadiene, polyurethane, ethylene-vinyl acetate copolymer, polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate, polyethylene, polypropylene, ethylene-propylene copolymer, polymethylpentene, polyimide, and polyamide, and a release film formed by applying a release agent on the surface of these films can be listed. Among these, polyester, polyimide, and polyamide are preferred, and polyethylene terephthalate as a kind of polyester is more preferred.

[0317] The thickness of the film of the present embodiment is not particularly limited, but is preferably 10 μm to 100 μm, more preferably 10 μm to 50 μm, from the viewpoint of ensuring the filling property of the underfill material between the connection terminals during mounting.

[0318] [Laminated body]

[0319] The laminate of the present embodiment comprises: a supporting substrate and a layer including the thin film of the present embodiment laminated on the supporting substrate. Such a laminate is obtained by attaching the thin film of the present embodiment to the supporting substrate.

[0320] The thickness of the supporting substrate is not particularly limited, but is preferably 10 μm to 100 μm from the aspects of the manufacturability of the laminate, such as the stability of the coating thickness when the thin film is coated on the supporting substrate, and the transportability of the laminate. As the lower limit of the thickness of the supporting substrate, from the aspect of ensuring the yield when manufacturing the laminate, it is more preferably 12 μm or more, more preferably 25 μm or more, and even more preferably 30 μm or more. As the upper limit of the thickness of the supporting substrate, from the aspect that the supporting substrate will not ultimately exist as a constituent member of the semiconductor device but will be peeled off during the process and from the aspect of the manufacturing cost of the laminate, it is more preferably 80 μm or less, and even more preferably 50 μm or less.

[0321] The method for manufacturing the laminate of the present embodiment by forming a layer (hereinafter also referred to as "film layer") containing the film of the present embodiment on a supporting substrate is not particularly limited. As such a manufacturing method, for example, the following method can be cited: a varnish in which the film of the present embodiment is dissolved or dispersed in an organic solvent is applied to the surface of the supporting substrate, heated and / or dried under reduced pressure, and the solvent is removed to solidify the film of the present embodiment to form a film layer. The drying conditions are not particularly limited, and the drying is performed in a manner such that the content ratio of the organic solvent to the film layer is generally 10 parts by mass or less, preferably 5 parts by mass or less, relative to the total amount (100 parts by mass) of the film layer. The conditions for achieving the drying also vary depending on the type and compounding amount of the organic solvent in the varnish. For example, in the case of a varnish containing 10 to 300 parts by mass of methyl ethyl ketone relative to 100 parts by mass of the total of the acrylic resin (A) and the radical polymerizable resin or compound (B) containing a maleimide group, it is recommended to dry the varnish under heating conditions of 90° C. to 160° C. at 1 atmosphere for about 2 to 10 minutes. It should be noted that the above-mentioned thin film layer can function as an insulating layer.

[0322] [Semiconductor wafer with thin film layer, and semiconductor mounting substrate with thin film layer]

[0323] The semiconductor wafer with a thin film layer of the present embodiment comprises a semiconductor wafer and a laminate of the present embodiment stacked on the semiconductor wafer, wherein the layer including the thin film is stacked on the semiconductor wafer. In addition, the semiconductor mounting substrate with a thin film layer of the present embodiment comprises a semiconductor mounting substrate and a laminate of the present embodiment stacked on the semiconductor mounting substrate, wherein the layer including the thin film is stacked on the semiconductor mounting substrate.

[0324] The method for producing the semiconductor wafer with the thin film layer of the present embodiment is not particularly limited, and it can be obtained, for example, by bonding the thin film layer of the laminated body of the present embodiment to the surface of the semiconductor wafer on which the electrode is formed, that is, the surface to be bonded to the substrate, in a manner opposite to each other. In addition, the method for producing the semiconductor mounting substrate with the thin film layer of the present embodiment is not particularly limited, and it can be obtained, for example, by bonding the thin film layer of the laminated body of the present embodiment to the surface of the chip mounting side of the semiconductor mounting substrate in a manner opposite to each other.

[0325] There is no particular limitation on the method of laminating the laminate of the present embodiment to the semiconductor wafer or the semiconductor mounting substrate, and a vacuum pressurized laminator can be used appropriately. In this case, it is preferred to pressurize and laminate the laminate of the present embodiment with the aid of an elastic body such as rubber. There is no particular limitation on the laminating conditions as long as they are the conditions commonly used in the industry, for example, at a temperature of 50°C to 140°C and a pressure of 1 kgf / cm 2 ~11kgf / cm2 The lamination process is carried out under a contact pressure in the range of and an atmosphere pressure reduction of 20 hPa or less. After the lamination process, the laminated body can also be smoothed by hot pressing using a metal plate. The lamination process and the smoothing process can be carried out continuously using a commercially available vacuum pressure laminator. In any case, the laminate attached to the semiconductor wafer or the semiconductor mounting substrate is removed from the supporting substrate before the flip chip installation of the chip.

[0326] [Semiconductor devices]

[0327] The semiconductor device of the present embodiment comprises a semiconductor wafer with a thin film layer of the present embodiment, and / or a semiconductor mounting substrate with a thin film layer of the present embodiment. The method for manufacturing the semiconductor device of the present embodiment is not particularly limited, and for example, the following method can be cited: thinning the semiconductor wafer with a thin film layer of the present embodiment by means of grinding or the like, and performing singulation based on a dicing saw or the like to make a chip with a thin film layer, which is mounted on a semiconductor mounting substrate. In addition, the chip can also be mounted on a semiconductor mounting substrate with a thin film layer of the present embodiment. In the method of mounting a chip with a thin film layer on a semiconductor mounting substrate, and the method of mounting a semiconductor chip on a semiconductor mounting substrate with a thin film layer, a flip chip welding machine corresponding to the thermal compression method can be appropriately used. In addition, in the present embodiment, for convenience, the case of flip-chip mounting a chip on a semiconductor mounting substrate is described, but the object for flip-chip mounting the chip and applying the thin film of the present embodiment can also be an object other than a semiconductor mounting substrate. For example, the film of this embodiment can also be used for the joint between the semiconductor wafer and the chip when the chip is mounted on the semiconductor wafer, and the joint between each chip in the chip stack that is connected to each other via TSV (Through Silicon Via) technology, etc. In any case, the advantages brought by the present invention can be obtained.

[0328] Example

[0329] Hereinafter, the present embodiment will be described in more detail using examples and comparative examples. The present embodiment is not limited at all by the following examples.

[0330] [Production of thin films and laminates]

[0331] (Example 1)

[0332] 60 parts by mass (30 parts by mass in terms of nonvolatile content) of a methyl ethyl ketone (MEK) solution (50% nonvolatile content) of an acryl-containing resin represented by formula (25) (BPN01-S (trade name), manufactured by Gunei Chemical Industry Co., Ltd., mass average molecular weight: 1830) as the acryl-containing resin (A), 33 parts by mass of a maleimide compound represented by formula (5) (BMI-1000P (trade name), manufactured by KI Chemical Industry Co., Ltd.) as the radical polymerizable resin or compound (B), bis-(3-ethyl-5-methyl-4-maleimidophenyl)methane (BMI-70 (trade name), manufactured by KI Chemical Industry Co., Ltd.) methyl ethyl ketone (MEK) solution (non-volatile matter 50% by mass) 14 parts by mass (7 parts by mass in terms of non-volatile matter), 2,2-bis(4-(4-maleimidephenoxy)phenyl)propane (BMI-80 (trade name), KI Chemical Industry Co., Ltd.) in MEK solution (50% by mass of nonvolatile matter), 14 parts by mass (7 parts by mass in terms of nonvolatile matter), 77 parts by mass (23 parts by mass in terms of nonvolatile matter) of a maleimide compound represented by formula (7) (MIR-3000-70MT (trade name), manufactured by Nippon Kayaku Co., Ltd., 30% by mass of nonvolatile matter), 66 parts by mass (33 parts by mass in terms of nonvolatile matter) of a Pd-type benzoxazine (manufactured by Shikoku Chemical Industry Co., Ltd., (trade name), 3,3'-(methylene-1,4-diphenylene)bis(3,4-dihydro-2H-1,3-benzoxazine), hydroxyl equivalent: 217, molecular weight: 434) in MEK solution (50% by mass of nonvolatile matter), and rosin-modified maleic acid resin (MALKYD) as an organic compound having a fluxing function. 54 parts by mass (27 parts by mass in terms of nonvolatile content) of a MEK solution (nonvolatile content 50% by mass) of No. 32 (trade name), manufactured by Arakawa Chemical Industries, Ltd.), 266 parts by mass (133 parts by mass in terms of nonvolatile content) of a MEK solution of slurry silica (YA050C-MJE (trade name), solid content 50% by mass, average particle size: 50 nm, manufactured by ADMATECH CO., LTD.) as an inorganic filler (G), and bis(1-methyl-1-phenylethyl) peroxide (diisopropylbenzene peroxide, manufactured by Kishida Chemical Co., Ltd., 10-hour half-life temperature: 116.4°C) and 4 parts by mass of 2-ethyl-4-methylimidazole (2E4MZ, manufactured by Shikoku Chemical Industry Co., Ltd.) as an imidazole compound (E) were mixed, and stirred for 40 minutes using a high-speed stirring device to obtain a varnish (MEK amount: 264 parts by mass). It should be noted that the ratio of the propylene group (eq. / 100g-resin) in the propylene-containing resin (A) to the polymerizable functional group (maleimide group) (eq. / 100g-resin) in the free radical polymerizable resin or compound (B) (propylene group: polymerizable functional group) is 1:2. The varnish was applied to a polyethylene terephthalate film (TR1-38 (trade name), manufactured by Unitika Ltd.) with a thickness of 38 μm and a release agent coated on the surface, and heated and dried at 100°C for 5 minutes to obtain a laminate having a film layer with a thickness of 30 μm obtained from the varnish. It should be noted that the film layer is in a semi-cured state (B-stage). .

[0333] (Example 2)

[0334] A varnish was prepared in the same manner as in Example 1 except that 42 parts by mass (21 parts by mass) of a MEK solution (50% nonvolatile content) of a propylene-containing resin (TPMP01 (trade name), manufactured by Gunei Chemical Industry Co., Ltd., mass average molecular weight: 2371) represented by formula (26) was added instead of 60 parts by mass (30 parts by mass in terms of nonvolatile content) of the propylene-containing resin (BPN01-S (trade name)) represented by formula (25) as the propylene-containing resin (A), and 77 parts by mass (23 parts by mass in terms of nonvolatile content) of the maleimide compound (MIR-3000-70MT (trade name)) represented by formula (7) as the radical polymerizable resin or compound (B) was changed to 107 parts by mass (32 parts by mass in terms of nonvolatile content). It should be noted that the ratio of the acrylic group (eq. / 100g-resin) in the acrylic group-containing resin (A) to the polymerizable functional group (maleimide group) (eq. / 100g-resin) in the radical polymerizable resin or compound (B) (acrylic group: polymerizable functional group) is 1:2. Using this varnish, the same operation as in Example 1 was performed to obtain a laminate having a film layer having a thickness of 30 μm obtained from the varnish. It should be noted that the film layer was in a semi-cured state (B-stage).

[0335] (Example 3)

[0336] As the propylene-containing resin (A), 60 parts by mass (30 parts by mass as non-volatile components) of the propylene-containing resin (BPN01-S (trade name)) represented by formula (25) was changed to 22 parts by mass (11 parts by mass as non-volatile components), as the radical polymerizable resin or compound (B), 33 parts by mass of the maleimide compound (BMI-1000P (trade name)) represented by formula (5) was changed to 47 parts by mass, and 77 parts by mass (23 parts by mass as non-volatile components) of the maleimide compound (MIR-3000-70MT (trade name)) represented by formula (7) was changed to 93 parts by mass (28 parts by mass as non-volatile components), and as the organic compound (H) having a fluxing function, a rosin-modified maleic acid resin (MALKYD No. 32 (trade name)) was changed from 54 parts by mass (27 parts by mass as non-volatile components) to 80 parts by mass (40 parts by mass as non-volatile components). The same operation as in Example 1 was performed except that the varnish was prepared. It should be noted that the ratio of the propylene group (eq. / 100g-resin) in the propylene-containing resin (A) to the polymerizable functional group (maleimide group) (eq. / 100g-resin) in the radical polymerizable resin or compound (B) (propylene group: polymerizable functional group) was 1:7. Using the varnish, the same operation as in Example 1 was performed to obtain a laminate having a thickness of 30 μm of the thin film layer obtained from the varnish. It should be noted that the thin film layer was in a semi-cured state (B-stage).

[0337] (Example 4)

[0338] A varnish was prepared in the same manner as in Example 1, except that the maleimide compound (MIR-3000-70MT (trade name)) represented by formula (7) was not blended as the radical polymerizable resin or compound (B), 7 parts by mass (14 parts by mass as non-volatile component) of the maleimide compound (bis-(3-ethyl-5-methyl-4-maleimidephenyl)methane, BMI-70 (trade name)) was changed to 36 parts by mass (18 parts by mass as non-volatile component), and 7 parts by mass (14 parts by mass as non-volatile component) of the maleimide compound (2,2-bis(4-(4-maleimidephenoxy)phenyl)propane, BMI-80 (trade name)) was changed to 38 parts by mass (19 parts by mass as non-volatile component). It should be noted that the ratio of the acrylic group (eq. / 100g-resin) in the acrylic group-containing resin (A) to the polymerizable functional group (maleimide group) (eq. / 100g-resin) in the radical polymerizable resin or compound (B) (acrylic group: polymerizable functional group) is 1:2. Using this varnish, the same operation as in Example 1 was performed to obtain a laminate having a film layer having a thickness of 30 μm obtained from the varnish. It should be noted that the film layer was in a semi-cured state (B-stage).

[0339] (Example 5)

[0340] A varnish was prepared in the same manner as in Example 1 except that 77 parts by mass (23 parts by mass in terms of nonvolatile components) of the maleimide compound (MIR-3000-70MT (trade name)) represented by formula (4) was added instead of 77 parts by mass (23 parts by mass in terms of nonvolatile components) of the maleimide compound (MIR-3000-70MT (trade name)) represented by formula (7). The ratio of the acryl group (eq. / 100 g-resin) in the acryl group-containing resin (A) to the polymerizable functional group (maleimide group) (eq. / 100 g-resin) in the radical polymerizable resin or compound (B) (acrylic group: polymerizable functional group) was 1:2. Using this varnish, the same manner as in Example 1 was used to obtain a laminate having a film layer having a thickness of 30 μm obtained from the varnish. It should be noted that the thin film layer is in a semi-cured state (B-stage).

[0341] (Comparative Example 1)

[0342] A varnish was prepared in the same manner as in Example 1 except that 77 parts by mass (23 parts by mass as non-volatile components) of the maleimide compound (MIR-3000-70MT (trade name)) represented by formula (7) was changed to 177 parts by mass (53 parts by mass as non-volatile components) and the acryl-containing resin (BPN01-S (trade name)) represented by formula (25) was not used. Using the varnish, the same manner as in Example 1 was used to obtain a laminate having a film layer having a thickness of 30 μm obtained from the varnish.

[0343] (Comparative Example 2)

[0344] A varnish was prepared in the same manner as in Example 1 except that 36 parts by mass (18 parts by mass) of a MEK solution (50% nonvolatile content) of a vinyl group-containing resin (LVA01 (trade name), manufactured by Gunei Chemical Industry Co., Ltd.) represented by formula (27) was added in place of 60 parts by mass (30 parts by mass in terms of nonvolatile content) of the acryl-containing resin (BPN01-S (trade name)) represented by formula (25), and 77 parts by mass (23 parts by mass in terms of nonvolatile content) of the maleimide compound (MIR-3000-70MT (trade name)) represented by formula (7) was changed to 117 parts by mass (35 parts by mass in terms of nonvolatile content). Using this varnish, a laminate having a thin film layer having a thickness of 30 μm obtained from the varnish was obtained in the same manner as in Example 1.

[0345]

[0346] Using this varnish, the same operation as in Example 1 was carried out to obtain a laminated body having a thin film layer having a thickness of 30 μm obtained from the varnish.

[0347] [Evaluation of Laminated Body]

[0348] (1) Curing

[0349] The thin film layer obtained from the varnish in the laminated body obtained in Examples 1 to 5 and Comparative Examples 1 and 2 was crushed to obtain a resin powder. The obtained resin powder was measured for calorific value in the range of 30°C to 350°C using a differential scanning calorimeter (Q100 (trade name), manufactured by TA Instruments Inc.). The curing property was evaluated by recording the calorific value (W / g) at 120°C as A for a value of 0.01W / g or more, B for a value of 0.006W / g or more and less than 0.01W / g, and C for a value of less than 0.006W / g. When the calorific value is 0.01W / g or more, a film having excellent filling properties in semiconductor chip mounting using a flip chip bonding machine is obtained. The results are shown in Table 1.

[0350] (2) Gap

[0351] The laminates obtained in Examples 1 to 5 and Comparative Examples 1 and 2 were cut into 8 mm × 8 mm squares, and the thin film layer obtained from the varnish in the cut laminate was laminated on the evaluation substrate. Thereafter, the polyethylene terephthalate film in the laminate was peeled off. Thereafter, a flip chip bonding machine (LFB-2301 (trade name), manufactured by Shinkawa Co., Ltd.) was used to thermally press the thin film layer on the peeled surface onto a semiconductor chip having a Cu column composed of copper and solder on the electrode under the conditions of a workbench temperature of 70°C, a bonding head temperature of 260°C, a load of 50N, and a time of 6 seconds, and the semiconductor chip was mounted. An ultrasonic precision flaw detection image processing device (μ-SDS (trade name), manufactured by KJTD Co., Ltd.) was used to confirm the presence or absence of voids in the thin film layer within the range of the semiconductor chip mounting portion of the mounted sample (semiconductor chip / thin film layer / evaluation substrate). The evaluation was performed by marking the case where the void ratio was less than 10% as A, the case where the void ratio was 10% or more and less than 30% as B, and the case where the void ratio was 30% or more as C. When the void ratio was less than 10%, a laminate with high insulation reliability was obtained.

[0352] (3) Chip adhesiveness

[0353] The laminate obtained in Examples 1 to 5 and Comparative Examples 1 and 2 was cut into a square of 8 mm × 8 mm, and the thin film layer obtained from the varnish in the cut laminate was stacked on the surface of the evaluation substrate and laminated. Thereafter, the polyethylene terephthalate film in the laminate was peeled off. Thereafter, a flip chip bonding machine (LFB-2301 (trade name), manufactured by Shinkawa Co., Ltd.) was used to thermally press the thin film layer on the peeled surface onto a semiconductor chip having a Cu column composed of copper and solder on the electrode under the conditions of a workbench temperature of 70°C, a bonding head temperature of 260°C, a load of 50N, and a time of 6 seconds, and the installation was performed. The cross section of the central part of the sample (semiconductor chip / thin film layer / evaluation substrate) after installation was cut out, and the peeling at the interface between the semiconductor chip and the thin film layer was confirmed in its cross section using a scanning electron microscope (JCM-6000Plus (trade name), manufactured by JEOL Ltd.). The case where the peeling ratio is less than 1% is recorded as A, the case where the peeling ratio is more than 1% and less than 20% is recorded as B, and the case where the peeling ratio is more than 20% is recorded as C for evaluation. When the peeling ratio is less than 1%, a laminate with high insulation reliability is obtained. The results are shown in Table 1. It should be noted that in Table 1, when there are many gaps during semiconductor mounting and the thin film layer is present in a small part near the semiconductor chip, the chip adhesion cannot be measured, and it is recorded as "-".

[0354] (4) Minimum melt viscosity

[0355] The thin film layer obtained from the varnish in the laminated bodies obtained in Examples 1 to 5 and Comparative Examples 1 and 2 was crushed, and 1 g of the obtained resin powder was weighed. The tablet was formed into a sheet with a diameter of 25 mm and a thickness of 1.5 mm using a tablet forming machine (SSP-10A (trade name), manufactured by Shimadzu Corporation) under the conditions of a pressure of 20 kN and a time of 5 minutes. The viscosity in the range of 40°C to 260°C was measured using a rheometer (ARES-G2 (trade name), manufactured by TA Instruments Inc.) at a temperature increase rate of 10°C / min. The case where the minimum melt viscosity was 10,000 Pa·s or more and less than 30,000 Pa·s was recorded as A, and the case where the minimum melt viscosity was 30,000 Pa·s or more or less than 10,000 Pa·s was recorded as B. The results are shown in Table 1.

[0356] [Table 1]

[0357] evaluate Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Curing A A A A A B C Gap A A A B B B C Die Attach A A B A B C - Minimum melt viscosity A A A A B B B

[0358] This application is based on the Japanese patent application (Japanese Patent Application No. 2019-122429) filed on June 28, 2019, the contents of which are incorporated herein by reference.

[0359] Industrial Applicability

[0360] The film of this embodiment has various effects such as curability, low voids, and excellent chip bonding, and is therefore suitable as a pre-underfill material. In addition, the film of this embodiment also has excellent fluxing activity, so that a laminate obtained by bonding a chip to a substrate, a chip to a semiconductor wafer, or a chip to a chip can be given high reliability that can withstand long-term use.

Claims

1. Use of a film in pre-application of an underfill material, the film comprising: Containing propylene-based resin (A); a radical polymerizable resin or compound (B) other than the propylene group-containing resin (A); and Curing accelerator (C), a thermosetting compound (F) other than the acrylic group-containing resin (A) and the radical polymerizable resin or compound (B), The propylene group-containing resin (A) comprises a resin represented by the following formula (2): In formula (2), W each independently represents a hydrocarbon group having 6 to 15 carbon atoms and having an aromatic ring, U each independently represents a hydrogen atom or an alkenyl group having 2 to 6 carbon atoms, and n 1 represents the number of repetitions, whose average value is a real number from 1 to 20. The radical polymerizable resin or compound (B) comprises at least one selected from the group consisting of a maleimide group and a citraconimide group, The curing accelerator (C) comprises a thermal free radical polymerization initiator (D) and an imidazole compound (E), The thermosetting compound (F) comprises a benzoxazine compound, in, The content of the curing accelerator (C) is 0.05 to 10 parts by mass relative to 100 parts by mass of the total of the acrylic group-containing resin (A) and the radical polymerizable resin or compound (B). The content of the thermosetting compound (F) is 1 to 100 parts by mass relative to 100 parts by mass of the total of the acrylic group-containing resin (A) and the radical polymerizable resin or compound (B). The acryl groups in the acryl-containing resin (A) and the polymerizable functional groups in the free radical polymerizable resin or compound (B) are calculated as eq. / 100g-resin respectively, and the ratio of the acryl groups in the acryl-containing resin (A) to the polymerizable functional groups in the free radical polymerizable resin or compound (B), i.e., acryl groups: polymerizable functional groups, is 1:1 to 1:7, and the polymerizable functional groups in the free radical polymerizable resin or compound (B) represent maleimide groups and / or citraconimide groups.

2. The use according to claim 1, wherein The mass average molecular weight of the propylene-containing resin (A) is 300 to 10,000.

3. The use according to claim 1 or 2, wherein The propylene group-containing resin (A) comprises a resin represented by the following formula (3): In formula (3), Y each independently represents a hydrocarbon group having 1 to 6 carbon atoms, X each independently represents a hydrogen atom or an alkenyl group having 2 to 6 carbon atoms, and n 2 Represents the number of repetitions, whose average value is a real number between 1 and 20.

4. The use according to claim 1 or 2, wherein The radical polymerizable resin or compound (B) comprises at least one selected from the group consisting of 2,2-bis[4-(4-maleimidephenoxy)phenyl]propane, a maleimide compound represented by the following formula (4), a maleimide compound represented by the following formula (5), a maleimide compound represented by the following formula (6), a maleimide compound represented by the following formula (7), a maleimide compound represented by the following formula (8), and a maleimide compound represented by the following formula (9), In formula (4), R 1 Each independently represents a hydrogen atom or a methyl group, n 3 represents an integer from 1 to 10, In formula (5), n 4 represents an integer from 1 to 30, In formula (6), R 2 Each independently represents a hydrogen atom, a methyl group, or an ethyl group, and R 3 each independently represents a hydrogen atom or a methyl group, In formula (7), R 4 Each independently represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a phenyl group, l each independently represents an integer of 1 to 3, and n 5 represents an integer from 1 to 10, In formula (8), R 5 and R 7 Each independently represents a hydrocarbon group consisting of 8 or more atoms connected in a straight chain, R 6 Each independently represents a substituted or unsubstituted cyclic hydrocarbon group having 4 to 10 atoms constituting the ring and optionally containing a hetero atom, n 6 represents an integer from 1 to 10, In formula (9), R 8 Each independently represents an alkylene group, R 9 Each independently represents an alkylene group, a group represented by the following formula (10), a group represented by the formula "-SO2-", a group represented by "-CO-", a group represented by the following formula (11), an oxygen atom, or a single bond, and n 7 represents an integer from 1 to 10, In formula (10), Z is an alkylene group or a hydrocarbon group having 6 to 30 carbon atoms and containing an aromatic ring, and n 8 represents an integer from 0 to 5, 5. The use according to claim 1, wherein The 10-hour half-life temperature of the thermal radical polymerization initiator (D) is 100° C. or higher.

6. The use according to claim 1, wherein The thermal radical polymerization initiator (D) contains an organic peroxide.

7. The use according to claim 1, wherein The thermal radical polymerization initiator (D) has a peroxyester, peroxyketal, dialkyl peroxide, or hydroperoxide skeleton.

8. The use according to claim 1, wherein The thermal radical polymerization initiator (D) includes at least one selected from the group consisting of diisopropylbenzene peroxide, di(2-tert-butylperoxyisopropyl)benzene, 1,1,3,3-tetramethylbutyl hydroperoxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)-3-hexyne, and tert-butyl hydroperoxide.

9. The use according to claim 1, wherein The thermosetting compound (F) has a molecular weight of 400 or more.

10. The use according to claim 1, wherein The benzoxazine compound comprises at least one selected from the group consisting of a compound represented by the following formula (12), a compound represented by the following formula (13), a compound represented by the following formula (14), and a compound represented by the following formula (15), In formula (12), R 10 Each independently represents an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group, and R 11 represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, a cycloalkyl group, or a monovalent to tetravalent organic group represented by the following general formulae (a) to (t), n 9 represents an integer from 1 to 4, In formula (13), R 12 Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group, and R 13 represents an aryl group, an aralkyl group, an alkenyl group, an alkyl group, a cycloalkyl group, or a monovalent to tetravalent organic group represented by the following general formulae (a) to (t), n 10 represents an integer from 1 to 4, In formula (14), R 14 represents an alkyl group, a cycloalkyl group, or a phenyl group which may have a substituent, In formula (15), R 15 represents an alkyl group, a cycloalkyl group, or a phenyl group which may have a substituent, In formulas (a) to (t), R a represents an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group, and R b represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group.

11. The use according to claim 1, wherein The benzoxazine compound comprises at least one selected from the group consisting of a compound represented by the following formula (23) and a compound represented by the following formula (24), In formula (23), R 16 Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group, o each independently represents an integer of 1 to 4, and R 17 Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group, each independently represents an integer of 1 to 4, and T 1 represents an alkylene group, a group represented by the following formula (10), a group represented by the formula "-SO2-", a group represented by "-CO-", an oxygen atom, or a single bond, In formula (24), R 18 Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group, q each independently represents an integer of 1 to 3, and R 19 Each independently represents a hydrogen atom, an aryl group, an aralkyl group, an alkenyl group, an alkyl group, or a cycloalkyl group, each independently represents an integer of 1 to 5, and T 2 represents an alkylene group, a group represented by the following formula (10), a group represented by the formula "-SO2-", a group represented by "-CO-", an oxygen atom, or a single bond, In formula (10), Z is an alkylene group or a hydrocarbon group having 6 to 30 carbon atoms and containing an aromatic ring, and n 8 Indicates an integer from 0 to 5.

12. The use according to claim 1 or 2, wherein The film further comprises an inorganic filler material (G).

13. The use according to claim 12, wherein The average particle size of the inorganic filler (G) is 3 μm or less.

14. The use according to claim 12, wherein The inorganic filler (G) includes at least one selected from the group consisting of silica, aluminum hydroxide, aluminum oxide, boehmite, boron nitride, aluminum nitride, magnesium oxide, and magnesium hydroxide.

15. The use according to claim 12, wherein The inorganic filler (G) is silicon dioxide.

16. The use according to claim 12, wherein The content of the inorganic filler (G) is 500 parts by mass or less based on 100 parts by mass of the total of the acrylic group-containing resin (A) and the radical polymerizable resin or compound (B).

17. The use according to claim 1 or 2, wherein The film further comprises an organic compound (H) having a fluxing function.

18. The use according to claim 17, wherein The content of the organic compound (H) having a fluxing function is 5 to 80 parts by mass based on 100 parts by mass of the total of the acrylic group-containing resin (A) and the radical polymerizable resin or compound (B).

19. The use according to claim 1 or 2, wherein the film has a thickness of 10 μm to 100 μm.

Images