JP4655488B2 - Circuit connection material, film-like circuit connection material using the same, circuit member connection structure, and manufacturing method thereof - Google Patents

Description

  The present invention relates to a circuit connection material, a film-like circuit connection material using the circuit connection material, a circuit member connection structure, and a manufacturing method thereof.

  In the fields of the electric industry and the electronic industry, various adhesive materials are used for the purpose of bonding various circuit members. In particular, in the field of semiconductor elements and liquid crystal display elements, higher density and higher definition have been promoted, and adhesives applied to these applications are required to have excellent adhesive strength.

In addition, the adherend bonded with an adhesive includes organic substrates such as printed wiring boards and polyimides, metals such as copper and aluminum, ITO (indium tin oxide), silicon nitride (SiN _x ), and silicon dioxide. Substrates having various surface states such as (SiO ₂ ) are used, and it is desired that the adhesive be designed according to each adherend.

  Thermosetting resins such as epoxy resins have been conventionally used as adhesives for semiconductor elements and liquid crystal display elements (see, for example, Patent Document 1). Such an adhesive is cured by heat treatment at 170 to 250 ° C. for 1 to 3 hours.

  For this reason, with the recent high integration of semiconductor elements and high definition of liquid crystal display elements, the temperature between 170 and 250 ° C. is used as described above in a situation where the pitch between elements and wirings is narrowed. When heat treatment of the adhesive is performed, the heating during curing may adversely affect the peripheral members. Therefore, in order to prevent adverse effects on the peripheral members, it is required to be cured at a low temperature (100 to 170 ° C.), and further, to be cured in a short time (within 1 hour) in order to improve the throughput. Is also required. In other words, an adhesive for “low temperature fast curing” is required.

  In order to meet such a requirement, Patent Document 2 discloses an anisotropic conductive adhesive containing a radical polymerizable resin, an organic peroxide, a thermoplastic elastomer, a phosphate ester, and an epoxy silane coupling agent as a resin composition. Is disclosed.

Japanese Patent Laid-Open No. 1-113480 JP 2000-44905 A

  However, although the anisotropic conductive adhesive described in Patent Document 2 can be cured at a low temperature, the circuit member connection structure obtained by connecting the circuit member using the adhesive after storage can be obtained. The stability of the connection resistance was insufficient.

  The present invention has been made in view of the above-described problems of the prior art. A circuit connection material having excellent stability of connection resistance after storage, a film-like circuit connection material using the same, and a circuit member connection structure and It aims at providing the manufacturing method.

  In order to solve the above problems, the circuit connection material of the present invention includes a first circuit member in which a first circuit electrode is formed on a main surface of a first circuit board, and a main surface of a second circuit board. A circuit connection material for connecting a second circuit member, on which a second circuit electrode is formed, in a state where the first circuit electrode and the second circuit electrode are arranged to face each other, It contains an adhesive composition containing a polymerizable compound and a radical polymerization initiator, and conductive particles surface-treated with a compound having a nitrogen-silicon bond.

  Since the circuit connection material of the present invention contains conductive particles surface-treated with a compound having a nitrogen-silicon bond as a conductive material, it is placed between the electrodes of the opposing circuit members and cured, and then between the electrodes. A sufficiently low connection resistance can be obtained. The circuit connection material of the present invention is excellent in the stability of the connection resistance after storage. Here, the stability of the connection resistance after storage is obtained by using a circuit connection material that is left for a predetermined time after manufacture with respect to the connection resistance in the circuit member connection structure obtained using the circuit connection material immediately after manufacture. It means that the fluctuation of the connection resistance in the circuit member connection structure is sufficiently suppressed.

  Moreover, since the circuit connection material of this invention contains the adhesive composition containing a radically polymerizable compound and a radical polymerization initiator, low temperature rapid hardening is possible.

  The film-like circuit connecting material of the present invention is formed by forming the circuit connecting material into a film shape. The film-like circuit connecting material is easy to handle, can be easily installed on the adherend, and can be easily connected.

The circuit member connection structure of the present invention includes a first circuit member in which a first circuit electrode is formed on the main surface of the first circuit board, and a second circuit on the main surface of the second circuit board. A second circuit member on which an electrode is formed; and a first circuit electrode and a second circuit electrode provided between the main surface of the first circuit board and the main surface of the second circuit board. A circuit connection member for connecting the first and second circuit members in a state of being opposed to each other, and a circuit member connection structure comprising:
The circuit connection member is made of a cured product of the circuit connection material of the present invention, and the first circuit electrode and the second circuit electrode are electrically connected via conductive particles whose surface is treated with a compound having a nitrogen-silicon bond. It is characterized by being connected to. In this circuit member connection structure, since the circuit connection member is made of a cured product of the circuit connection material, the connection resistance between the first circuit electrode and the second circuit electrode is sufficiently reduced and stable. Yes.

The method for manufacturing a circuit member connection structure according to the present invention includes a first circuit member in which a first circuit electrode is formed on a main surface of a first circuit board, and a first circuit member on a main surface of a second circuit board. A first circuit electrode and a second circuit electrode provided between the second circuit member on which the second circuit electrode is formed and the main surface of the first circuit board and the main surface of the second circuit board; And a circuit connection member that connects the first and second circuit members in a state of facing each other, and a manufacturing method of a circuit member connection structure comprising:
The circuit connection material of the present invention is disposed between the main surface of the first circuit board and the main surface of the second circuit board, and the circuit connection material is heated and pressurized via the first and second circuit members. Then, a circuit member connection structure is manufactured by connecting the first circuit member and the second circuit member by curing. According to the method for manufacturing a circuit member connection structure, by using the circuit connection material of the present invention, low temperature rapid curing is possible, adverse effects on the circuit member are sufficiently suppressed, and throughput can be improved. Become.

  The circuit connection material of the present invention is excellent in stability of connection resistance after storage, can be cured at low temperature, and is suitable for bonding circuit members (for example, semiconductor elements and liquid crystal display elements). Moreover, the connection structure of the circuit member produced using such a circuit connection material has a sufficiently reduced connection resistance and is stable. Furthermore, according to the method for manufacturing a circuit member connection structure using such a circuit connection material, low temperature rapid curing is possible, so that adverse effects on the circuit member are sufficiently suppressed and throughput can be improved. .

  Preferred embodiments of the present invention will be described below with reference to the accompanying drawings as the case may be. In addition, the same code | symbol shall be used for the same element and the overlapping description is abbreviate | omitted. In the following description, (meth) acrylate means acrylate or a corresponding methacrylate.

(Circuit connection material)
The circuit connection material of the present invention includes a first circuit member in which a first circuit electrode is formed on the main surface of the first circuit board, and a second circuit electrode on the main surface of the second circuit board. A circuit connection material for connecting the formed second circuit member in a state where the first circuit electrode and the second circuit electrode are arranged to face each other, comprising a radical polymerizable compound and a radical polymerization initiator And an electrically conductive particle surface-treated with a compound having a nitrogen-silicon bond.

  First, the adhesive composition contained in the circuit connection material of the present invention will be described. The adhesive composition contains at least a radical polymerizable compound and a radical polymerization initiator.

  The radical polymerizable compound is a compound having a functional group that is polymerized by radicals. Examples of the radical polymerizable compound include a (meth) acrylate compound, a maleimide compound, a citraconimide compound, and a nadiimide compound. These may be used alone or in combination of two or more. Moreover, the radically polymerizable compound can be used in any state of a monomer or an oligomer, and a monomer and an oligomer may be mixed and used.

  (Meth) acrylate compounds include methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, isobutyl (meth) acrylate, etherene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, and trimethylol. Propane tri (meth) acrylate, tetramethylene glycol tetra (meth) acrylate, 2-hydroxy-1,3-diaacryloxypropane, 2,2-bis [4- (acryloxymethoxy) phenyl] propane, 2,2- Bis [4- (acryloxyethoxy) phenyl] propane, dicyclopentenyl (meth) acrylate tricyclodecanyl (meth) acrylate, tris (acryloxyethyl) isocyanurate, urethane (meth) acrylate , And the like isocyanuric acid ethylene oxide-modified diacrylate. These may be used alone or in combination of two or more. A (meth) acrylic resin is obtained by radical polymerization of the (meth) acrylate compound.

  A maleimide compound is a compound having at least one maleimide group. As maleimide compounds, phenylmaleimide, 1-methyl-2,4-bismaleimidebenzene, N, N′-m-phenylenebismaleimide, N, N′-p-phenylenebismaleimide, N, N′-4,4 -Biphenylene bismaleimide, N, N'-4,4- (3,3-dimethylbiphenylene) bismaleimide, N, N'-4,4- (3,3-dimethyldiphenylmethane) bismaleimide, N, N'- 4,4- (3,3-diethyldiphenylmethane) bismaleimide, N, N′-4,4-diphenylmethane bismaleimide, N, N′-4,4-diphenylpropane bismaleimide, N, N′-4,4 -Diphenyl ether bismaleimide, N, N'-4,4-diphenylsulfone bismaleimide, 2,2-bis (4- (4-maleimidophenol) Xyl) phenyl) propane, 2,2-bis (3-s-butyl-3,4- (4-maleimidophenoxy) phenyl) propane, 1,1-bis (4- (4-maleimidophenoxy) phenyl) decane, 4,4'-cyclohexylidene-bis (1- (4-maleimidophenoxy) phenoxy) -2-cyclohexylbenzene, 2,2-bis (4- (4-maleimidophenoxy) phenyl) hexafluoropropane . These may be used alone or in combination of two or more.

  A citraconic imide compound is a compound having at least one citraconic imide group. Citraconimide compounds include phenyl citraconimide, 1-methyl-2,4-biscitraconimide benzene, N, N′-m-phenylene biscitraconimide, N, N′-p-phenylene biscitraconimide, N, N '-4,4-biphenylenebiscitraconimide, N, N'-4,4- (3,3-dimethylbiphenylene) biscitraconimide, N, N'-4,4- (3,3-dimethyldiphenylmethane) bis Citraconimide, N, N′-4,4- (3,3-diethyldiphenylmethane) biscitraconimide, N, N′-4,4-diphenylmethanebiscitraconimide, N, N′-4,4-diphenylpropanebis Citraconimide, N, N′-4,4-diphenyl ether biscitraconimide, N, N′-4,4- Phenylsulfone biscitraconimide, 2,2-bis (4- (4-citraconimidophenoxy) phenyl) propane, 2,2-bis (3-s-butyl-3,4- (4-citraconimidophenoxy) phenyl) Propane, 1,1-bis (4- (4-citraconimidophenoxy) phenyl) decane, 4,4′-cyclohexylidene-bis (1- (4-citraconimidophenoxy) phenoxy) -2-cyclohexylbenzene, 2 , 2-bis (4- (4-citraconimidophenoxy) phenyl) hexafluoropropane and the like. These may be used alone or in combination of two or more.

  A nadiimide compound is a compound having at least one nadiimide group. Examples of the nadiimide compound include phenyl nadiimide, 1-methyl-2,4-bisnadiimidebenzene, N, N′-m-phenylenebisnadiimide, N, N′-p-phenylenebisnadiimide, N, N′-4, 4-biphenylenebisnadiimide, N, N′-4,4- (3,3-dimethylbiphenylene) bisnadiimide, N, N′-4,4- (3,3-dimethyldiphenylmethane) bisnadiimide, N, N′-4 , 4- (3,3-diethyldiphenylmethane) bisnadiimide, N, N′-4,4-diphenylmethanebisnadiimide, N, N′-4,4-diphenylpropanebisnadiimide, N, N′-4,4-diphenyl ether Bisnadiimide, N, N′-4,4-diphenylsulfone bisnadiimide, 2,2-bis (4- (4-nadiimidophenol) Xyl) phenyl) propane, 2,2-bis (3-s-butyl-3,4- (4-nadiimidophenoxy) phenyl) propane, 1,1-bis (4- (4-nadiimidophenoxy) phenyl) Decane, 4,4′-cyclohexylidene-bis (1- (4-nadiimidophenoxy) phenoxy) -2-cyclohexylbenzene, 2,2-bis (4- (4-nadiimidophenoxy) phenyl) hexafluoropropane Etc. These may be used alone or in combination of two or more.

［上記式中、ｎは１〜３の整数を示す。］ Furthermore, as the radical polymerizable compound, a radical polymerizable compound having a phosphate ester structure may be used, and a radical polymerizable compound having a phosphate ester structure represented by the following formula (I) is preferable.

[In the above formula, n represents an integer of 1 to 3. ]

  A radically polymerizable compound having a phosphate structure is preferable because it can improve the adhesive force of the adhesive composition to an inorganic substance such as a metal. The amount of the radical polymerizable compound having a phosphate ester structure is preferably from 0.1 to 30 parts by weight, more preferably from 0.5 to 10 parts by weight, based on 100 parts by weight of the solid content of the adhesive composition. 0.5-5 mass parts is further more preferable. The radically polymerizable compound having a phosphoric ester structure is obtained as a reaction product of phosphoric anhydride and 2-hydroxyethyl (meth) acrylate. Specific examples include mono (2-methacryloyloxyethyl) acid phosphate, di (2-methacryloyloxyethyl) acid phosphate (phosphate ester dimethacrylate), and the like. These may be used alone or in combination of two or more.

  As the radical polymerizable compound, it is preferable to use a combination of a (meth) acrylate compound and a radical polymerizable compound having a phosphate ester structure. In the case of such a combination, the adhesive strength of the adhesive composition is further improved as compared with the case where each of the (meth) acrylate compound and the radical polymerizable compound having a phosphate ester structure is used alone.

  The radical polymerization initiator is not particularly limited as long as it is a compound that generates radicals by light irradiation and / or heating. As such a radical polymerization initiator, a compound that generates a radical upon irradiation with light of 150 to 750 nm and / or heating at 80 to 200 ° C. is preferable, and specifically, a peroxide, an azo compound, or the like is preferable. These are appropriately selected in consideration of the intended connection temperature, connection time, storage stability, and the like.

  As the peroxide, an organic peroxide is preferable from the viewpoint of high reactivity and storage stability. Organic peroxide having a half-life of 10 hours at a temperature of 40 ° C or higher and a half-life of 1 minute at a temperature of 180 ° C or lower. Organic peroxides having a half-life of 10 hours at a temperature of 50 ° C. or more and a half-life of 1 minute at a temperature of 170 ° C. or less are particularly preferred. When the connection time is 10 seconds or less, the blending amount of the radical polymerization initiator for obtaining a sufficient reaction rate is preferably 1 to 20% by mass based on the total solid content of the adhesive composition, preferably 2 ˜15% by weight is particularly preferred.

  Specific examples of the organic peroxide include diacyl peroxide, peroxydicarbonate, peroxyester, peroxyketal, dialkyl peroxide, hydroperoxide, silyl peroxide, and the like. Among them, peroxyesters, dialkyl peroxides, hydroperoxides, and silyl peroxides have a chlorine ion or organic acid concentration of 5000 ppm or less in the initiator, and less organic acids are generated after thermal decomposition. Since corrosion of an electrode can be suppressed, it is particularly preferable.

  Diacyl peroxide includes isobutyl peroxide, 2,4-dichlorobenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, lauroyl peroxide, stearoyl peroxide, succinic peroxide, benzoyl Examples include peroxytoluene and benzoyl peroxide.

  Examples of peroxydicarbonate include di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, bis (4-t-butylcyclohexyl) peroxydicarbonate, di-2-ethoxymethoxyperoxydicarbonate, di ( 2-ethylhexyl peroxy) dicarbonate, dimethoxybutyl peroxydicarbonate, di (3-methyl-3-methoxybutylperoxy) dicarbonate and the like.

  Peroxyesters include cumylperoxyneodecanoate, 1,1,3,3-tetramethylbutylperoxyneodecanoate, 1-cyclohexyl-1-methylethylperoxynoedecanoate, and t-hexyl. Peroxyneodecanoate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-di (2- Ethylhexanoylperoxy) hexane, 1-cyclohexyl-1-methylethylperoxy-2-ethylhexanoate, t-hexylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate Nate, t-butylperoxyisobutyrate, 1,1-bis (t-butylperoxy) cyclohexane, -Hexylperoxyisopropyl monocarbonate, t-butylperoxy-3,5,5-trimethylhexanonate, t-butylperoxylaurate, 2,5-dimethyl-2,5-di (m-toluoyl par Oxy) hexane, t-butyl peroxyisopropyl monocarbonate, t-butyl peroxy-2-ethylhexyl monocarbonate, t-hexyl peroxybenzoate, t-butyl peroxyacetate and the like.

  Peroxyketals include 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, 1,1-bis (t- Butyl peroxy) -3,3,5-trimethylcyclohexane, 1,1- (t-butylperoxy) cyclododecane, 2,2-bis (t-butylperoxy) decane and the like.

  Dialkyl peroxides include α, α′-bis (t-butylperoxy) diisopropylbenzene, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, and t-butyl. Cumyl peroxide and the like.

  Examples of the hydroperoxide include diisopropylbenzene hydroperoxide and cumene hydroperoxide.

  Examples of silyl peroxides include t-butyltrimethylsilyl peroxide, bis (t-butyl) dimethylsilyl peroxide, t-butyltrivinylsilyl peroxide, bis (t-butyl) divinylsilyl peroxide, and tris (t-butyl). Examples thereof include vinylsilyl peroxide, t-butyltriallylsilyl peroxide, bis (t-butyl) diallylsilyl peroxide, and tris (t-butyl) allylsilyl peroxide.

  These radical polymerization initiators can be used singly or in combination of two or more, and may be used by mixing a decomposition accelerator, an inhibitor and the like.

  In addition, those obtained by coating these radical polymerization initiators with a polyurethane-based or polyester-based polymeric substance to form a microcapsule are preferable because the pot life is extended.

  When the adhesive composition is used as a circuit connecting material, the concentration of chlorine ions and organic acids contained in the radical polymerization initiator is 5000 ppm or less in order to suppress corrosion of circuit electrodes of circuit members. It is preferable. Furthermore, a radical polymerization initiator that generates less organic acid after thermal decomposition is more preferable. Moreover, since the stability after hardening of adhesive composition improves, it is preferable to have a mass retention of 20 mass% or more after leaving open for 24 hours at room temperature and normal pressure.

  Moreover, adhesive composition may contain radical polymerization inhibitors, such as hydroquinone and methyl ether hydroquinone, in the range which does not impair sclerosis | hardenability as needed.

  The adhesive composition may include a thermosetting resin other than the radical polymerizable compound. Examples of such a thermosetting resin include an epoxy resin. Epoxy resins include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A novolak type epoxy resin, bisphenol F novolak type epoxy resin, fat Examples thereof include cyclic epoxy resins, glycidyl ester type epoxy resins, glycidyl amine type epoxy resins, hydantoin type epoxy resins, isocyanurate type epoxy resins, and aliphatic chain epoxy resins. These epoxy resins may be halogenated or hydrogenated. These epoxy resins may be used alone or in combination of two or more.

  Moreover, what is used as a hardening | curing agent of a normal epoxy resin can be used as a hardening | curing agent of the said epoxy resin. Specific examples include amines, phenols, acid anhydrides, imidazoles, dicyandiamide and the like. Furthermore, tertiary amines and organic phosphorus compounds that are usually used as curing accelerators may be used as appropriate.

  Further, as a method of reacting the epoxy resin, in addition to using the above curing agent, cationic polymerization may be performed using a sulfonium salt, an iodonium salt, or the like.

  The adhesive composition may contain a polymer compound in order to impart film formability, adhesiveness, and stress relaxation during curing. Examples of the polymer compound include polyvinyl butyral resin, polyvinyl formal resin, polyester resin, polyamide resin, polyimide resin, xylene resin, phenoxy resin, polyurethane resin, urea resin, and the like.

  These polymer compounds preferably have a molecular weight of 10,000 to 10,000,000. Further, these polymer compounds may be modified with radically polymerizable functional groups, and in this case, heat resistance is improved. Furthermore, these polymer compounds may contain a carboxyl group. The blending amount of the polymer compound in the adhesive composition is preferably 2 to 80% by mass, more preferably 5 to 70% by mass, and particularly preferably 10 to 60% by mass with respect to the total solid content in the adhesive composition. preferable. When the blending amount of the polymer compound is less than 2% by mass, stress relaxation and adhesive force tend to be insufficient. On the other hand, when it exceeds 80 mass%, it exists in the tendency for fluidity | liquidity to fall.

  You may add a filler, a softening agent, an accelerator, an anti-aging agent, a coloring agent, a flame retardant, and a coupling agent to an adhesive composition suitably.

  In the adhesive composition demonstrated above, it is preferable to contain 0.5-30 mass parts of radical polymerization initiators with respect to 100 mass parts of radically polymerizable compounds, and containing 1.0-10 mass parts. More preferred. When the content of the radical polymerization initiator is less than 0.5 parts by mass, the curing reaction does not proceed sufficiently and the curing tends to be insufficient. On the other hand, when it exceeds 30 mass parts, there exists a tendency for storage stability to fall.

  Next, conductive particles surface-treated with a compound having a nitrogen-silicon bond in the molecule (hereinafter referred to as “surface-treated conductive particles”) will be described. The surface-treated conductive particles can be obtained by adding conductive particles to a solution containing a compound having a nitrogen-silicon bond in the molecule, stirring, and separating the conductive particles from the solution. More specifically, conductive particles are added to a solution in which a compound having a nitrogen-silicon bond in the molecule is dissolved in a predetermined solvent, and stirred for a predetermined time. At this time, the temperature of the solution is preferably 20 to 40 ° C., and the stirring time is preferably 3 to 30 minutes. As the solvent, an organic solvent such as methyl ethyl ketone is used. Next, the conductive particles are filtered off from the solution and dried. As a result, surface-treated conductive particles are obtained.

  Here, the conductive particles are not particularly limited as long as they have conductivity capable of obtaining electrical connection, but include metal particles such as Au, Ag, Ni, Cu, Co, and solder, carbon, and the like. . In addition, non-conductive glass, ceramics, plastics, or the like coated with a conductive material such as the metal can be used. At this time, the thickness of the metal layer to be coated is preferably 10 nm or more in order to obtain sufficient conductivity.

  As the compound having a nitrogen-silicon bond in the molecule, a known compound can be used without particular limitation. The compound having a nitrogen-silicon bond in the molecule is preferably at least one selected from the group consisting of a silazane compound, silylamine, and aminosilane. Of these, silazane compounds are particularly preferred.

As a silazane compound, any of a polymer, an oligomer, and a monomer may be sufficient.
Specific examples of the silazane compound include hexamethyldisilazane, 1,1,3,3-tetramethyl-1,3-divinyldisilazane, tetramethyl-1,3-diphenyldisilazane, 1,1,1. , 3,3,3-hexamethyldisilazane, 2,2,4,4,6,6-hexamethylcyclotrisilazane, heptamethyldisilazane, octamethylcyclotetrasilazane, 1,1,3,3-tetra Methyldisilazane, allyldimethyl (diisopropylamino) silane, trimethylsilylaniline, 1,3-bis (chloromethyl) tetramethyldisilazane, bis (diethylamino) dimethylsilane, bis (dimethylamino) diethylsilane, bis (dimethylamino) dimethyl Silane, bis (dimethylaminodimethylsilyl) ethane, bis (dimethylamino) Diphenylsilane, bis (dimethylamino) methylsilane, bis (dimethylamino) vinylethylsilane, bis (dimethylamino) vinylmethylsilane, bis (ethylamino) dimethylsilane, bis (N-methylbenzamido) ethoxymethylsilane, 1,3 -Bis (3,3,3-trifluoropropyl) tetramethyldisilazane, N-6,9-bis (trimethylsilyl) adenine, N, N'-bis (trimethylsilyl) -1,4-butanediamine, bis (trimethylsilyl) ) Cytosine, N, O-bis (trimethylsilyl) hydroxylamine, n-butyldimethyl (dimethylamino) silane, chloromethylsilatrane, m-chlorophenoxysilatrane, 3-cyanopropyl (diisopropyl) dimethylaminosilane, 3-cyanopropyl Tylcyclosilazane, di-n-butyltetramethyldisilazane, (diethylamino) trimethylsilane, (diisopropylamino) trimethylsilane, (N, N-dimethylamino) dimethylsilane, (N, N-dimethylamino) dimethylchlorosilane, dimethyl Aminomethylethoxysilane, (N, N-dimethylamino) triethylsilane, (N, N-dimethylamino) trimethylsilane, 1,3-di-n-octyltetramethyldisilazane, 1,3-diphenyl-1,1 , 3,3-tetramethyldisilazane, 1,3-dipropyl-1,1,3,3-tetramethyldisilazane, 1,3-divinyl-1,3-diphenyl-1,3-dimethyldisilazane, , 1,3,3,5,5-hexamethylcyclotrisilazane, 1,2,3,4,5,6- Oxamethylcyclotrisilazane, hydroxyethoxysilatrane, methacrylamidetrimethylsilane, methacryloxypropylsilatrane, methylsilatrane, methyl-N-trimethylsilylcarbamate, N-methyl-N-trimethylsilyltrifluoroacetamide, nonamethyltrisilazane, n -Octadecyldiisobutyl (dimethylamino) silane, n-octadecyldimethyl (dimethylamino) silane, n-octyldimethyl (dimethylamino) silane, phenylbis (dimethylamino) chlorosilane, phenylmethylbis (dimethylamino) silane, 1,3, 5,7-tetraethyl-2,4,6,8-tetramethylcyclotetrasilazane, tetrakis (diethylamino) silane, tetrakis (dimethylamino) silane, 2,2 , 5,5-tetramethyl-2,5-disila-1-azacyclopentane, 1,1,3,3-tetraphenyldimethyldisilazane, 1,3,5,7-tetravinyl-1,3,5 , 7-tetramethylcyclotetrasilazane, 1,2,3-triethyl-2,4,6-trimethylcyclotrisilazane, tri-n-hexylsilylamine, N- (trimethylsilyl) acetamide, m-trimethylsilylaminophenylacetylene, N- (trimethylsilyl) morpholine, 3-trimethylsilyl-2-oxazolidinone, 1-trimethylsilylpyrrole, 1-trimethylsilyl-1,2,4-triazole, tris (cyclohexylamino) methylsilane, tris (dimethylamino) chlorosilane, tris (dimethylamino) ) Ethylsilane, Tris (Dime Ruamino) methylsilane, tris (dimethylamino) phenylsilane, tris (dimethylamino) silane, 1,3,5-trivinyl-1,3,5-trimethylcyclotrisilazane, (N-vinylformamido) trimethylsilane, vinylsilatrane 1-trimethylsilylpyrrolidone, poly (1,1-dimethylsilazane), poly (1,2-dimethylsilazane) and the like. You may use these individually by 1 type or in mixture of 2 or more types.

  Examples of silylamine include N, N-diethyl-1,1,1-trimethylsilylamine, N, N-diisopropyltrimethylsilylamine, N, O-bis (trimethylsilyl) acetamide, N-6,9-bis (trimethylsilyl) adenine, bis (Trimethylsilyl) cytosine, N, O-bis (trimethylsilyl) hydroxylamine and the like can be mentioned. These may be used alone or in combination of two or more.

  As aminosilane, allylaminotrimethylsilane, allyldimethyl (diisopropylamino) silane, anilinotrimethylsilane, bis (diethylamino) dimethylsilane, bis (dimethylamino) diethylsilane, bis (dimethylamino) dimethylsilane, bis (dimethylamino) Examples include diphenylsilane, bis (dimethylamino) dimethylsilane, bis (dimethylamino) vinylethylsilane, bis (N-methylbenzamido) ethoxymethylsilane, and n-butyldimethyl (dimethylamino) silane. These may be used alone or in combination of two or more.

  Further, the content of the surface-treated conductive particles in the circuit connecting material is preferably 0.1 to 30% by volume, more preferably 1.0 to 20% by volume with respect to the total amount of the circuit connecting material. . When the content is less than 0.1% by volume, it tends to be difficult to obtain good conduction. On the other hand, if it exceeds 30% by volume, there is a possibility of causing a short circuit (short circuit) of the adjacent circuit.

  Moreover, the usage form of the circuit connecting material is not particularly limited. For example, the surface-treated conductive particles are dispersed in a solution obtained by dissolving each component in the adhesive composition in an organic solvent such as toluene or ethyl acetate. be able to. Moreover, it can also use as a molded object (for example, film-form circuit connection material mentioned later) which removed the solvent from the solution in which the said surface treatment electroconductive particle was disperse | distributed and shape | molded in the predetermined shape.

  FIG. 1 is a schematic cross-sectional view showing an embodiment of a film-like circuit connecting material. A film-like circuit connecting material 1 shown in FIG. 1 includes an adhesive composition containing the above-described radical polymerizable compound and radical polymerization initiator, and surface-treated conductive particles 7. According to this film-like circuit connecting material, it is easy to handle, can be easily installed on the adherend, and can be easily connected.

  In addition, the film-form circuit connection material 1 is good also as a multilayer structure (not shown) which consists of 2 or more types of layers from which Tg (glass transition temperature) of an adhesive composition differs 5 degreeC or more when it hardens | cures.

  The film-like circuit connecting material 1 is prepared by, for example, applying an adhesive composition dissolved in a solvent and dispersing surface-treated conductive particles on a support (PET (polyethylene terephthalate) film or the like) using a coating apparatus. It can be produced by drying with hot air for a predetermined time at a temperature at which the adhesive composition does not cure.

  The thickness of the film-like circuit connecting material is preferably 10 to 50 μm. If the thickness of the film-like circuit connecting material is less than 10 μm, the circuit connecting material tends to be insufficiently filled between the facing circuit members. On the other hand, when it exceeds 50 μm, the adhesive composition between the circuit electrodes cannot be sufficiently removed, and it tends to be difficult to ensure conduction between the circuit electrodes.

(Circuit member connection structure)
FIG. 2 is a schematic cross-sectional view showing an embodiment of the circuit member connection structure of the present invention. As shown in FIG. 2, the circuit member connection structure of the present embodiment includes a first circuit member 20 and a second circuit member 30 that are opposed to each other. A circuit connection member 10 is provided between the circuit member 30 and the circuit member 30.

  The first circuit member 20 includes a circuit board (first circuit board) 21 and a circuit electrode (first circuit electrode) 22 formed on the main surface 21 a of the circuit board 21. Note that an insulating layer (not shown) may be formed on the main surface 21a of the circuit board 21 in some cases.

  On the other hand, the second circuit member 30 includes a circuit board (second circuit board) 31 and a circuit electrode (second circuit electrode) 32 formed on the main surface 31 a of the circuit board 31. In addition, an insulating layer (not shown) may be formed on the main surface 31a of the circuit board 31 according to circumstances.

The first and second circuit members 20 and 30 are not particularly limited as long as electrodes that require electrical connection are formed. Specific examples include glass or plastic substrates with electrodes formed of ITO or the like used for liquid crystal displays, printed wiring boards, ceramic wiring boards, flexible wiring boards, semiconductor silicon chips, and the like. Used in combination accordingly. As described above, in this embodiment, a material made of an organic substance such as a printed wiring board or polyimide, a metal such as copper or aluminum, ITO (indium tin oxide), silicon nitride (SiN _x ), silicon dioxide (SiO ₂ ). Circuit members having various surface states such as inorganic materials such as the above can be used.

  The circuit connection member 10 contains an insulating substance 11 and surface-treated conductive particles 7. The surface-treated conductive particles 7 are disposed not only between the circuit electrode 22 and the circuit electrode 32 facing each other, but also between the main surfaces 21a and 31a. In the circuit member connection structure, the circuit electrodes 22 and 32 are electrically connected via the surface-treated conductive particles 7. That is, the surface-treated conductive particles 7 are in direct contact with both the circuit electrodes 22 and 32.

  In this circuit member connection structure, as described above, the facing circuit electrode 22 and the circuit electrode 32 are electrically connected via the surface-treated conductive particles 7. For this reason, the connection resistance between the circuit electrodes 22 and 32 is sufficiently reduced. Therefore, the flow of current between the circuit electrodes 22 and 32 can be made smooth, and the functions of the circuit can be fully exhibited.

  Since the circuit connection member 10 is composed of a cured product of the circuit connection material including the adhesive composition and the surface-treated conductive particles, the circuit connection member 10 is sufficiently low and stable between the circuit electrodes 22 and 32 of the circuit members 20 and 30. Connection resistance is obtained.

(Method for manufacturing circuit member connection structure)
Next, a method for manufacturing the circuit member connection structure described above will be described.

  First, the first circuit member 20 and the film-like circuit connecting material 40 described above are prepared (see FIG. 3A). The film-like circuit connecting material 40 is formed by forming a circuit connecting material into a film shape, and the film-like circuit connecting material 40 is the same as the film-like circuit connecting material 1. That is, the circuit connection material includes the above-described adhesive composition containing the radical polymerizable compound and at least a radical polymerization initiator that generates radicals upon heating.

  Next, the film-like circuit connecting material 40 is placed on the surface of the first circuit member 20 on which the circuit electrodes 22 are formed. When the film-like circuit connecting material 40 is attached on a support (not shown), the film-like circuit connecting material 40 side is directed to the first circuit member 20 so that the first circuit is connected. Place on member 20. At this time, the film-like circuit connecting material 40 is film-like and easy to handle. For this reason, the film-like circuit connecting material 40 can be easily interposed between the first circuit member 20 and the second circuit member 30, and the first circuit member 20 and the second circuit member 30 Connection work can be performed easily.

  And the film-form circuit connection material 40 is pressurized to the arrow A and B direction of Fig.3 (a), and the film-form circuit connection material 40 is temporarily connected to the 1st circuit member 20 (refer FIG.3 (b)). . At this time, you may pressurize, heating. However, the heating temperature is a temperature at which the adhesive composition in the film-like circuit connecting material 40 is not cured, that is, a temperature lower than the temperature at which the radical polymerization initiator generates radicals.

  Subsequently, as shown in FIG. 3C, the second circuit member 30 is placed on the film-like circuit connection material 40 so that the second circuit electrode faces the first circuit member 20. In addition, when the film-form circuit connection material 40 has adhered on the support body (not shown), after peeling a support body, the 2nd circuit member 30 is mounted on the film-form circuit connection material 40. FIG.

  And it heats through the 1st and 2nd circuit members 20 and 30 to the arrow A and B direction of FIG.3 (c), heating the film-form circuit connection material 40. FIG. The heating temperature at this time is a temperature at which the radical polymerization initiator can generate radicals. As a result, radicals are generated in the radical polymerization initiator, and polymerization of the radical polymerizable compound is started. In this way, the film-like circuit connecting material 40 is cured, and the main connection is performed, so that a circuit member connection structure as shown in FIG. 2 is obtained.

  The heating temperature is, for example, 90 to 200 ° C., and the connection time is, for example, 1 second to 10 minutes. These conditions are appropriately selected depending on the application to be used, the adhesive composition, and the circuit member, and may be post-cured as necessary. Thus, since the film-form circuit connection material 40 has the structure mentioned above, it can connect at low temperature rather than the circuit connection material containing an epoxy resin etc.

  When the circuit member connection structure is manufactured as described above, in the obtained circuit member connection structure, the surface-treated conductive particles 7 can be brought into contact with both the circuit electrodes 22 and 32 facing each other. , 32 can be sufficiently reduced.

  Further, by heating the film-like circuit connecting material 40, the adhesive composition is cured with the distance between the circuit electrode 22 and the circuit electrode 32 sufficiently reduced to become the insulating substance 11, and the first circuit member 20 and the second circuit member 30 are firmly connected via the circuit connection member 10. That is, in the obtained circuit member connection structure, since the circuit connection member 10 is made of a cured product of the circuit connection material, the adhesive strength of the circuit connection member 10 with respect to the circuit member 20 or 30 is sufficient. The connection resistance between the circuit electrodes 22 and 32 of the circuit members 20 and 30 is sufficiently low.

  In the above embodiment, the adhesive composition includes at least a radical polymerization initiator that generates radicals upon heating. Instead of this radical polymerization initiator, radicals are generated only by light irradiation. A radical polymerization initiator may be used. In this case, when the film-like circuit connecting material 40 is cured, light irradiation may be performed instead of heating. Moreover, in the said embodiment, although the connection structure of a circuit member is manufactured using the film-form circuit connection material 40, it may replace with the film-form circuit connection material 40, and may use a circuit connection material. Even in this case, if the circuit connection material is dissolved in a solvent and the solution is applied to either the first circuit member 20 or the second circuit member 30 and dried, the first and second circuit members 20 are used. , 30 can interpose a circuit connecting material.

  In addition, in the manufacturing method of the circuit member connection structure, in addition to the radical polymerization initiator that generates radicals by heating or light irradiation, a radical polymerization initiator that generates radicals by ultrasonic waves, electromagnetic waves, or the like is used as necessary. May be.

  In addition to the surface-treated conductive particles 7, other conductive materials may be used. Examples of other conductive materials include conductive particles that are not surface-treated with a compound having a nitrogen-silicon bond in the molecule, particulate or short fiber carbon, and metal filaments such as Au-plated Ni wires.

  Hereinafter, the content of the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

(Conductive particles surface-treated with a compound having a nitrogen-silicon bond)
First, a nickel layer having a thickness of 0.2 μm is provided on the surface of particles having polystyrene as a core using nickel as a material, and a gold layer having a thickness of 0.04 μm is formed outside the nickel layer using gold as a material. Was provided. In this way, conductive particles (untreated conductive particles) having an average particle diameter of 5 μm were produced.

  Next, conductive particles having an average particle diameter of 5 μm were added to a mixed solution of 1 g of the silazane compound and 10 g of methyl ethyl ketone, and stirred at 30 ° C. for 5 minutes. After the conductive particles were filtered off, the particles were dried at 80 ° C. for 5 minutes to obtain conductive particles 1 to 3 surface-treated with a silazane compound. As the silazane compound, 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasilazane (Chisso Corporation) is used for the surface-treated conductive particles 1, and 1 is used for the surface-treated conductive particles 2. For 3-divinyl-1,3-diphenyl-1,3-dimethyldisilazane (Chisso Corporation) and surface-treated conductive particles 3, poly (1,2-dimethylsilazane) (Chisso Corporation) was used.

Example 1
50 g of phenoxy resin (trade name PKHC, manufactured by Union Carbide Co., Ltd., average molecular weight 45,000) in terms of mass ratio is toluene (boiling point 110.6 ° C., SP value 8.90) / ethyl acetate (boiling point 77.1 ° C., SP A value 9.10) = dissolved in a 50/50 mixed solvent to prepare a phenoxy resin solution having a solid content of 40% by mass.

  As the radical polymerizable compound, hydroxyethyl glycol dimethacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name: 80MFA) and phosphate ester dimethacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name: P-2M) were prepared.

  As a radical polymerization initiator, di-2-ethylhexyl peroxydicarbonate (manufactured by NOF Corporation, trade name Parroyl OPP) was prepared.

  The materials prepared as described above were blended at a solid mass ratio shown in Table 1, and the surface-treated conductive particles 1 were added and dispersed so as to be 3% by volume with respect to the total amount of the circuit connecting material. The obtained solution was applied to a fluororesin film having a thickness of 80 μm using a coating apparatus, and dried with hot air at 70 ° C. for 10 minutes to obtain a film-like circuit connection material having a thickness of 20 μm. The obtained film-like circuit connecting material showed sufficient flexibility at room temperature.

(Example 2)
A film-like circuit connecting material having a thickness of 20 μm was obtained in the same manner as in Example 1 except that the surface-treated conductive particles 2 were used instead of the surface-treated conductive particles 1. The obtained film-like circuit connecting material showed sufficient flexibility at room temperature.

(Example 3)
A film-like circuit connecting material having a thickness of 20 μm was obtained in the same manner as in Example 1 except that the surface-treated conductive particles 3 were used instead of the surface-treated conductive particles 1. The obtained film-like circuit connecting material showed sufficient flexibility at room temperature.

(Comparative Example 1)
A film-like circuit connecting material having a thickness of 20 μm is obtained in the same manner as in Example 1 except that conductive particles not subjected to surface treatment with a silazane compound (untreated conductive particles) are used instead of the surface-treated conductive particles 1. It was. The obtained film-like circuit connecting material showed sufficient flexibility at room temperature.

(Measurement of adhesive strength and connection resistance)
First, a flexible circuit board (FPC board) having 500 copper circuits having a line width of 50 μm, a pitch of 100 μm, and a thickness of 18 μm, and a glass substrate (thickness 1.1 mm, surface resistance 20 Ω / □) on a 0.2 μm oxide layer. An ITO substrate on which a thin layer of indium (ITO) was formed was prepared. The film-like circuit connecting materials of Examples 1 to 3 and Comparative Example 1 (untreated, width 2 mm) were placed between the FPC substrate and the ITO substrate, and a thermocompression bonding apparatus (heating method: constant heat type, Toray Engineering Co., Ltd.) For 15 seconds at 160 ° C. and 3 MPa. Thus, a circuit member connection structure (ITO / FPC connection structure) was produced using the film-like circuit connection materials of Examples 1 to 3 and Comparative Example 1.

  The resistance values between adjacent circuits of the ITO / FPC connection structures of Examples 1 to 3 and Comparative Example 1 were measured with a multimeter immediately after bonding. The resistance value is shown as an average (x + 3σ) of 150 resistances between adjacent circuits. The obtained results are shown in Table 2.

  Moreover, the adhesive strength of the ITO / FPC connection structure produced using the film-form circuit connection material of Examples 1-3 and the comparative example 1 was measured by the 90 degree peeling method based on JIS-Z0237. Here, Tensilon UTM-4 (peeling speed 50 mm / min, 25 ° C.) manufactured by Toyo Baldwin Co., Ltd. was used as a measuring device for adhesive strength. The obtained results are shown in Table 2.

(Open test (storage) test)
The film-like circuit connecting materials of Examples 1 to 3 and Comparative Example 1 were left open (in air) for 5 hours in a constant temperature and humidity chamber of 35 ° C. and 60% RH (open open (storage) test). Circuit member connection structures of Examples 1 to 3 and Comparative Example 1 (ITO / ITO) in the same manner as above except that the film-like circuit connection materials of Examples 1 to 3 and Comparative Example 1 after the open standing test were used FPC connection structure) was produced. The resistance value and adhesive strength between adjacent circuits of the obtained ITO / FPC connection structure were measured in the same manner as described above. The obtained results are shown in Table 2.

  It was confirmed that the film-like circuit connecting materials of Examples 1 to 3 exhibited good connection resistance and adhesive strength immediately after bonding and after an open standing test. In particular, in the circuit member connection structure using the film-like circuit connection material after the open standing test, it was confirmed that Examples 1 to 3 were excellent in stability of connection resistance. On the other hand, Comparative Example 1 containing untreated conductive particles showed a high connection resistance after the open standing test, and it was confirmed that the stability of the connection resistance was insufficient.

It is a schematic sectional drawing which shows one Embodiment of the film-form circuit connection material of this invention. It is a schematic sectional drawing which shows one Embodiment of the connection structure of the circuit member of this invention. (A)-(c) is a series of process drawings which connect a circuit member, respectively.

Claims (7)

A first circuit member having a first circuit electrode formed on the main surface of the first circuit board, and a second circuit member having a second circuit electrode formed on the main surface of the second circuit board And a circuit connection material for connecting the first circuit electrode and the second circuit electrode in a state of facing each other,
A circuit connecting material comprising: an adhesive composition containing a radical polymerizable compound and a radical polymerization initiator; and conductive particles surface-treated with a silazane compound. The circuit connection material according to claim 1 , wherein the radical polymerization initiator generates radicals by light irradiation and / or heating. Circuit connecting material according to claim 1 or 2, wherein of the radical polymerizable compound to 100 parts by mass, the radical polymerization initiator, characterized in that it contains 0.5 to 30 parts by weight. Based on the total amount of the circuit connecting material, circuit connecting material according to any one of claims 1 to 3, characterized in that it contains 0.1 to 30 vol% of the surface-treated conductive particles by the silazane compound . A circuit connection material according to any one of claims 1 to 4 , wherein the circuit connection material is formed into a film shape. A first circuit member having a first circuit electrode formed on the main surface of the first circuit board;
A second circuit member having a second circuit electrode formed on the main surface of the second circuit board;
The first circuit board is provided between the main surface of the first circuit board and the main surface of the second circuit board, and the first circuit electrode and the second circuit electrode are arranged to face each other. And a circuit connecting member for connecting the second circuit members,
A circuit member connection structure comprising:
The circuit connection member is made of a cured product of the circuit connection material according to any one of claims 1 to 4 .
The circuit member connection structure, wherein the first circuit electrode and the second circuit electrode are electrically connected through conductive particles surface-treated with the silazane compound. A first circuit member having a first circuit electrode formed on the main surface of the first circuit board;
A second circuit member having a second circuit electrode formed on the main surface of the second circuit board;
The first circuit board is provided between the main surface of the first circuit board and the main surface of the second circuit board, and the first circuit electrode and the second circuit electrode are arranged to face each other. And a circuit connecting member for connecting the second circuit members,
A circuit member connection structure manufacturing method comprising:
The circuit connection material according to any one of claims 1 to 4 is disposed between a main surface of the first circuit board and a main surface of the second circuit board.
A circuit member connection structure by connecting the first circuit member and the second circuit member by heating and pressurizing and curing the circuit connection material through the first and second circuit members. The manufacturing method of the connection structure of the circuit member characterized by manufacturing this.

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