CN107254264A - The attachment structure and its manufacture method of circuit connection material, circuit block - Google Patents

Abstract

The present invention relates to a circuit connection material, a connection structure of circuit components and a manufacturing method thereof. The circuit connection material of the present invention is used to electrically connect opposite circuit electrodes to each other, the circuit connection material includes an adhesive composition and conductive particles, and the conductive particles are formed of metal or nickel having a Vickers hardness of 300-1000 The nuclei and the outermost layer of noble metal covering the nuclei are massive particles with an average particle diameter of 5 to 20 μm, and irregularities are formed on the surface of the conductive particles.

Description

Circuit connection material, connection structure of circuit components and manufacturing method thereof

The application date of the original application is April 10, 2012, the application number is 201280023903.0 (international application number PCT/JP2012/059804), and the title of the invention is "circuit connection material, connection structure of circuit components and connection structure of circuit components" The divisional application of the Chinese patent application for the manufacturing method of ".

technical field

The present invention relates to a circuit connection material, a connection structure of circuit components, and a method for manufacturing the connection structure of circuit components.

Background technique

As adhesives for semiconductor elements and liquid crystal display elements, thermosetting resins such as epoxy resins that exhibit excellent adhesiveness and high reliability are used (for example, refer to Patent Document 1). As the constituent components of the adhesive, epoxy resins, curing agents such as phenolic resins reactive with epoxy resins, and thermolatent catalysts that promote the reaction between epoxy resins and curing agents are generally used. A thermolatent catalyst is an important factor in determining the curing temperature and curing speed of an adhesive, and various compounds have been used from the viewpoint of storage stability at room temperature and curing speed when heated.

In addition, recently, radically curable adhesives composed of radically polymerizable compounds such as acrylate derivatives and methacrylate derivatives, and peroxides as radical polymerization initiators have attracted attention. Radical-curable adhesives can be cured at low temperatures in a short period of time (for example, refer to Patent Documents 2 to 4).

prior art literature

patent documents

Patent Document 1: Japanese Patent Application Laid-Open No. 1-113480

Patent Document 2: Japanese Unexamined Patent Publication No. 2002-203427

Patent Document 3: International Publication No. 98/044067 Pamphlet

Patent Document 4: Japanese Patent Laid-Open No. 2005-314696

Contents of the invention

The problem to be solved by the invention

These adhesives are mainly used in the field of flat panel displays (FPD, hereinafter referred to as "FPD") such as liquid crystal panels, and are beginning to be used in printed wiring boards (Printed Wiring Board, hereinafter referred to as "PWB") and carrier tapes. Package (Tape Carrier Package, hereinafter referred to as "TCP") or chip on film (Chip On Flex, hereinafter referred to as "COF") connection. In the FPD field, a circuit connection material is used for connecting flexible printed circuit boards (Flexible Printed Circuits, hereinafter referred to as "FPC" as the case may be) and PWB, and gold plating is usually applied to the circuit. On the other hand, for PWBs where components such as chips and capacitors are to be mounted, mounting by soldering is the mainstream. In order to obtain good solderability, as a surface treatment of the circuit, a treatment to form a resin film containing an imidazole compound has been attempted. In addition, in large-scale female packages and the like, since the cost can be reduced by not using gold, an organic film is usually formed by treating with a solution containing an organic resin such as an imidazole compound (hereinafter referred to as "OSP treatment" depending on the case) (hereinafter, Depending on the situation, it is called "OSP film"). The use of the above-mentioned circuit connecting material has also been studied in the mounting of such an OSP-processed circuit board.

In addition, due to the trend of high-density mounting, the mainstream of the circuit board structure is a multi-layer structure. In order to release the heat during connection, via holes, through holes, etc. are provided near the connection part. Therefore, it takes a sufficient time to apply heat to the connection portion, but from the viewpoint of improving production efficiency, connection in a short time is required.

The fast-curing radical curing adhesive used in the connection between FPC and PWB in the FPD field can be cured in a short time, but when used on an OSP-treated substrate, it is different from that used for gold-plated substrates. There is a tendency that the connection resistance tends to increase more easily than the case of the substrate.

In addition, in applications that do not require fast curing connection, the general-purpose anion-curing epoxy resin adhesives exhibit good adhesion to OSP-treated substrates, but there is an increase in connection resistance after passing through a reflow furnace for soldering. Propensity.

Here, the object of the present invention is to provide a circuit connection material that can be cured in a short time and that can provide sufficiently high connection reliability when used on an OSP-processed substrate, a connection structure of circuit components using the same, and a circuit Manufacturing method of connecting structure of components.

means of solving problems

The inventors of the present invention conducted intensive studies on the above-mentioned problems, and as a result obtained the following knowledge and completed the invention described later: The main cause of the increase in connection resistance in the case of using the above-mentioned curable adhesive is that the OSP film itself is non-conductive. properties, and the OSP film of the circuit board hardens through the reflow oven for soldering.

That is, the present invention provides a circuit connection material, which is a circuit connection material for electrically connecting opposing circuit electrodes, comprising an adhesive composition and conductive particles, and the conductive particles have a Vickers hardness of 300 to 1000. Concavity and convexity are formed on the surface of the conductive particle by the core body made of metal and the outermost layer formed by the noble metal covering the surface of the core body, and having an average particle diameter of 5 to 20 μm lumpy particles.

In addition, the present invention provides a circuit connection material for electrically connecting opposing circuit electrodes, comprising an adhesive composition and conductive particles having a nucleus formed of nickel and The outermost layer of the noble metal covering the surface of the core is agglomerated particles with an average particle diameter of 5 to 20 μm, and irregularities are formed on the surface of the conductive particles.

The circuit connecting material of the present invention can be cured in a short time by containing both the above-mentioned conductive particles and the adhesive composition, and can also exhibit good connection reliability to an OSP-processed substrate.

As for the conductive particle in the circuit connection material of this invention, it is preferable that the height difference of an uneven|corrugated part is 70 nm - 2 micrometers. If the level difference of the unevenness|corrugation part is the said range, it will become easy to penetrate through the OSP film of a circuit electrode, and it will become easy to suppress the rise of connection resistance.

In the circuit connecting material of the present invention, the adhesive composition preferably contains a radical polymerizable substance and a curing agent that generates free radicals by heating, from the viewpoint of being able to cure in a shorter time.

Moreover, when the adhesive composition in the circuit connection material of this invention contains an epoxy resin and a latent curing agent, the connection reliability of the connection structure of a circuit component can be improved further.

Moreover, in the circuit connection material of this invention, it is preferable that at least one of the opposing circuit electrodes has a film containing an imidazole compound. When the circuit connecting material of the present invention contains both the above-mentioned conductive particles and the adhesive composition, even if the circuit electrode has a film containing an imidazole compound, good connectivity can be obtained in a short connection time.

The present invention provides a connection structure of circuit components, comprising: a first circuit component having a first circuit electrode formed on a main surface of a first circuit substrate; a second circuit electrode formed on a main surface of a second circuit substrate; In addition, the second circuit component in which the second circuit electrode is disposed opposite to the first circuit electrode is provided between the first circuit substrate and the second circuit substrate, and the first circuit component and the second circuit component are connected so that the first The circuit connection portion where the circuit electrode and the second circuit electrode are electrically connected; the circuit connection portion is a cured product of the above-mentioned film-form circuit connection material of the present invention.

In the circuit member connection structure of the present invention, it is preferable that at least one of the first circuit electrode and the second circuit electrode has a film containing an imidazole compound.

In the connection structure of circuit members using a conventional short-time curing type circuit connecting material, when the circuit electrode has an OSP film, it tends to be difficult to improve connectivity in a short time connection. On the other hand, in the connection structure of circuit components of the present invention, the circuit connection portion is a cured product of the circuit connection material of the present invention described above, whereby good connectivity can be obtained even with a shorter connection time. In addition, in the connection structure of the circuit components of the present invention, since the film formed of the imidazole compound-containing material forms the surface of the circuit electrodes, the circuit electrodes can be protected from oxidation and good solderability can be obtained. Further, the connection structure of the present invention has sufficiently high adhesive strength and connection reliability since circuit components are connected to each other using the above-mentioned circuit connection material of the present invention.

The invention provides a method for manufacturing a connection structure of circuit components, comprising the steps of: forming a first circuit component having a first circuit electrode formed on a main surface of a first circuit substrate and forming a first circuit electrode on a main surface of a second circuit substrate. The second circuit member having the second circuit electrode is arranged in such a manner that the first circuit electrode and the second circuit electrode face each other, and the above-mentioned film-like circuit connecting material is interposed between the first circuit electrode and the second circuit electrode arranged oppositely. In this state, the whole is heated and pressurized, and the first circuit member and the second circuit member are connected so that the first circuit electrode and the second circuit electrode are electrically connected. Regarding the manufacturing method of the connection structure of circuit components of the present invention, by interposing the above-mentioned circuit connection material of the present invention between the first circuit electrode and the second circuit electrode and heating and pressurizing, even shorter connection A connection structure of circuit components with good connectivity can also be obtained over time.

The present invention relates to the application of an adhesive as a circuit connection material for electrically connecting opposing circuit electrodes to each other, the adhesive comprising an adhesive composition and conductive particles, the conductive particles having a Vickers hardness of 300 Concavity and convexity are formed on the surface of the conductive particle by a nucleus made of a metal of ~1000 μm and an outermost layer of a noble metal covering the surface of the nucleus and an average particle diameter of 5 to 20 μm.

In addition, the present invention relates to the use of an adhesive as a circuit connection material for electrically connecting opposing circuit electrodes to each other, the adhesive comprising an adhesive composition and conductive particles having The nuclei and the outermost layer of noble metal covering the surface of the nuclei are lumpy particles with an average particle diameter of 5 to 20 μm, and irregularities are formed on the surface of the conductive particles.

The present invention relates to the use of an adhesive in the manufacture of a circuit connection material for electrically connecting opposing circuit electrodes to each other, the adhesive comprising an adhesive composition and conductive particles having a A core body made of a metal with a hardness of 300-1000, and an outermost layer formed of a noble metal covering the surface of the core body, and aggregate particles with an average particle size of 5-20 μm, and unevenness is formed on the surface of the conductive particle.

In addition, the present invention relates to the use of an adhesive comprising an adhesive composition and conductive particles having The nuclei made of nickel and the outermost layer of noble metal covering the surface of the nuclei are lumpy particles with an average particle diameter of 5 to 20 μm, and irregularities are formed on the surface of the conductive particles.

Invention effect

According to the present invention, it is possible to provide a circuit connection material, a connection structure of circuit components, and a connection structure of circuit components that can be cured in a short period of time and impart high connection reliability when used on an OSP-treated substrate. Production method.

Description of drawings

FIG. 1 is a cross-sectional view showing one embodiment of a circuit connection material.

FIG. 2 is a SEM image showing an example of the appearance of conductive particles.

FIG. 3 is a SEM image showing an example of an enlarged surface of conductive particles.

Fig. 4 is a cross-sectional view showing one embodiment of the connection structure.

Fig. 5 is a cross-sectional view showing one embodiment of the connection structure.

detailed description

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as necessary. However, the present invention is not limited to the following embodiments. Here, the same reference numerals are attached to the same elements in the drawings, and overlapping descriptions will be omitted. In addition, unless otherwise specified, positional relationships such as up, down, left, and right are based on the positional relationships shown in the drawings. Further, the dimensional ratios of the drawings are not limited to the illustrated ratios.

The circuit connection material according to the present embodiment is an adhesive for electrically connecting circuit electrodes. FIG. 1 is a cross-sectional view showing one embodiment of a circuit connection material. As shown in FIG. 1 , the circuit connecting material 1 is composed of a resin layer 3 and a plurality of conductive particles 8 dispersed in the resin layer 3 , and has a film-like shape.

Hereinafter, each constituent material of the circuit connection material 1 is demonstrated.

(conductive particles)

The conductive particles 8 are lumpy particles having a core made of a metal having a Vickers hardness of 300 to 1000, an outermost layer made of a noble metal covering the core, and a plurality of irregularities formed on the surface of the conductive particle. In addition, the conductive particles 8 are lumpy particles having a nucleus made of nickel and an outermost layer made of a noble metal covering the nucleus, and a plurality of irregularities are formed on the surface of the conductive particle. Here, the irregularities on the surface of the conductive particles are generated by the irregularities on the surface of the core body which will be described later.

FIG. 2 is a SEM image showing an example of the appearance of conductive particles, and FIG. 3 is a SEM image showing an example of an enlarged surface of conductive particles. As shown in FIG. 2 and FIG. 3 , the conductive particle of this embodiment is not spherical but agglomerated, and unevenness is formed on the surface. Such conductive particles 8 easily penetrate the non-conductive OSP film of the circuit electrode, and it is easy to suppress a rise in connection resistance. Therefore, using the circuit connection material 1 containing the said electroconductive particle 8, the connection structure of the circuit member excellent in connection reliability can be produced.

The nuclei of conductive particle 8 are preferably selected from at least one transition metal such as nickel, chromium, molybdenum, manganese, cobalt, iron, vanadium, titanium, platinum, iridium, osmium, tungsten, tantalum, niobium, zirconium, palladium, etc. Metal, more preferably nickel.

The Vickers hardness of the metal constituting the core is 300-1000, more preferably 400-800, still more preferably 500-700. If the Vickers hardness of the core body is less than 300, then there is a tendency that the conductive particles 8 are easily deformed and the repellency of the OSP film on the electrode is reduced. Good connection reliability.

The nucleosome has irregularities on its surface. Since the nuclei have irregularities on the surface, irregularities can be formed on the surface of the conductive particles. The method of forming unevenness on the surface of the nucleus is not particularly limited. For example, in the case of nickel as the nucleus, the nickel ore and carbon monoxide are reacted at room temperature by the carbonyl method to form a carbonyl nickel complex, and further heated above 100°C to make Carbon monoxide is desorbed, and nickel with irregularities formed on the surface can be obtained.

The height difference of the unevenness formed on the surface of the conductive particle 8 is preferably 70 nm to 2 μm, more preferably 90 nm to 1.5 μm, and still more preferably 120 nm to 1 μm. When the height difference of the concavo-convex part is 70 nm or more, the electrodes are easily embedded in the circuit having the OSP film, and the connection resistance after the reliability test tends to be suppressed. In addition, if the height difference of the asperities is within 2 μm, the adhesive composition is less likely to remain at the base of the protrusions of the asperities, and the connection resistance after the reliability test tends to be suppressed.

The average particle diameter of the conductive particle 8 is 5-20 micrometers, Preferably it is 8-20 micrometers, More preferably, it is 8-15 micrometers. If the average particle diameter is less than 5 μm, then the solidification of the resin layer 3 takes place before the conductive particles 8 contact the electrodes, and if it exceeds 20 μm, since the radius of curvature of the conductive particles 8 is large, the repellency of the OSP film on the electrodes decreases. Electrical conduction is difficult to achieve in any case. Here, the average particle diameter of the conductive particles specified in the present application is a measured value obtained by observing conductive particles (n number 50) by SEM image, and can be calculated, for example, by averaging the longest particle diameter part and the shortest particle diameter part.

The outermost layer of the conductive particles 8 is formed of a noble metal, preferably at least one metal selected from noble metals such as gold, silver, platinum, palladium, rhodium, iridium, ruthenium, osmium, etc., more preferably made of gold or platinum, and further It preferably consists of gold. By making the outermost layer of the conductive particle 8 from these metals, the pot life of the circuit connection material 1 can be made long enough.

The thickness of the outermost layer of conductive particles 8 is preferably 0.03 to 0.4 μm, more preferably 0.08 to 0.2 μm. If the thickness of the outermost layer is 0.03 μm or more, the conductivity of the conductive particles 8 tends to be maintained and the connection resistance is suppressed. If it is within 0.4 μm, the cost of forming the outermost layer of the core body is suppressed and the thickness is low. sexual predisposition. Here, the entire surface of the nuclei is preferably covered with the outermost layer made of noble metal, but a part of the nuclei, such as irregularities on the surface of the nuclei, may be exposed from the outermost layer within the range not departing from the effect of the present invention.

The compounding amount of conductive particles 8 in the circuit connecting material 1 is appropriately set according to the application, and usually, relative to 100 parts by volume of the adhesive composition (that is, the portion of the resin layer 3 other than the conductive particles 8 in the circuit connecting material 1) is Within the range of 0.1 to 30 parts by volume. Furthermore, from the viewpoint of preventing short circuit between adjacent circuit electrodes on the same circuit board, the compounding quantity of the conductive particle 8 is more preferably 0.1 to 10 parts by volume.

(adhesive composition)

The adhesive composition forming the resin layer 3 may contain a curing agent that generates free radicals and a radically polymerizable substance. In other words, the circuit connection material 1 may contain an adhesive composition containing a curing agent that generates free radicals and a radical polymerizable substance, and the conductive particles 8 . When the circuit connecting material 1 is heated, a crosslinked structure is formed in the adhesive composition due to polymerization of the radically polymerizable substance, and a cured product of the circuit connecting material 1 is formed. In this case, the circuit connecting material 1 functions as a radical curing adhesive.

The curing agent for generating free radicals used in the circuit connecting material 1 is a substance that is decomposed by heating such as a peroxide compound or an azo compound to generate free radicals. selected. The blending amount is based on the overall mass of the circuit connecting material 1, preferably 0.05 to 10 mass %, more preferably 0.1 to 5 mass % (based on the overall mass of the circuit connecting material 1 being 100 mass parts, preferably 0.05 to 10 mass parts , more preferably 0.1 to 5 parts by mass). The curing agent that generates free radicals can be specifically selected from diacyl peroxides, peroxydicarbonates, peroxyesters, peroxyketals, dialkyl peroxides, hydroperoxides, and the like. In addition, in order to suppress corrosion of connection terminals of circuit components, it is preferably selected from peroxyesters, dialkyl peroxides, and hydroperoxides, and more preferably selected from peroxyesters capable of obtaining high reactivity.

Examples of diacyl peroxides include 2,4-dichlorobenzoyl peroxide, 3,5,5,-trimethylhexanoyl peroxide, octanoyl peroxide, lauroyl peroxide Stearic acid peroxide, succinic peroxide, toluene benzoyl peroxide, benzoyl peroxide.

Examples of peroxydicarbonates include di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, bis(4-tert-butylcyclohexyl)peroxydicarbonate, di-2- Ethoxymethoxyperoxydicarbonate, bis(2-ethylhexylperoxydicarbonate), dimethoxybutylperoxydicarbonate and bis(3-methyl-3-methoxy Butyl peroxy) dicarbonate.

Examples of peroxyesters include 1,1,3,3,-tetramethylbutylperoxyneodecanoate, 1-cyclohexyl-1-methylethylperoxyneodecanoate, t- Hexylperoxyneodecanoate, tert-butylperoxypivalate, 1,1,3,3,-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl -2,5-bis(2-ethylhexanoylperoxy)hexane, 1-cyclohexyl-1-methylethylperoxy-2-ethylhexanoate, tert-hexylperoxy-2-ethylhexyl ester, tert-butylperoxy-2-ethylhexanoate, tert-butylperoxyisobutyrate, 1,1-bis(tert-butylperoxy)cyclohexane, tert-hexylperoxyisopropyl Monocarbonate, tert-butyl peroxy-3,5,5-trimethylhexanoate, tert-butyl peroxylaurate, 2,5-dimethyl-2,5-di(m-toluoyl peroxy (oxy)hexane, tert-butylperoxyisopropyl monocarbonate, tert-butylperoxy-2-ethylhexyl monocarbonate, tert-hexylperoxybenzoate and tert-butylperoxyacetate.

Examples of peroxyketals include 1,1-bis(tert-hexylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(tert-hexylperoxy)cyclohexane , 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-(tert-butylperoxy)cyclododecane and 2,2-bis-( tert-butylperoxy)decane.

Examples of dialkyl peroxides include α,α'bis(tert-butylperoxy)dicumylbenzene, dicumyl peroxide, 2,5-dimethyl-2,5- Di(tert-butylperoxy)hexane and tert-butylcumene peroxide.

Examples of hydroperoxides include dicumyl hydroperoxide and cumene hydroperoxide.

These curing agents that generate free radicals can be used alone or in combination, and can also be used in combination with decomposition accelerators, inhibitors, and the like. In addition, microencapsulation of these curing agents by coating them with polyurethane-based or polyester-based polymer materials is preferable because the usable time is prolonged.

The radically polymerizable substance used in the circuit connecting material 1 refers to a substance having a functional group polymerized by radicals, and examples thereof include acrylates, methacrylates, maleimide compounds, citraconimide resins, sodium Dick imide (najiimide) resin, etc. The amount of the radically polymerizable substance is preferably 20 to 50 parts by mass, more preferably 30 to 40 parts by mass, based on 100 parts by mass of the entire mass of the circuit connecting material 1 . The radically polymerizable substance may be used in any state of a monomer or an oligomer, and may be used in combination of a monomer and an oligomer.

Examples of the above-mentioned acrylates (including corresponding methacrylates, the same below) include, for example, methacrylates, ethacrylates, isopropyl acrylates, isobutyl acrylates, and ethylene glycol diacrylates. , diethylene glycol diacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, 2-hydroxy-1,3-diacryloyloxypropane, 2,2-bis[4- (acryloyloxymethoxy)phenyl]propane, 2,2-bis[4-(acryloyloxypolyethoxy)phenyl]propane, dicyclopentenyl acrylate, tricyclodecenyl Acrylates, tris(acryloyloxyethyl)isocyanurate, and urethane acrylates. These can be used individually or in combination of 2 or more types, and a polymerization inhibitor, such as hydroquinone and hydroquinone methyl ether, can also be used suitably as needed. Moreover, when it has a dicyclopentenyl group and/or a tricyclodecenyl group and/or a triazine ring, since heat resistance improves, it is preferable.

The above-mentioned maleimide compound is a compound containing at least two or more maleimide groups in the molecule, for example, 1-methyl-2,4-bismaleimide benzene, N,N '-m-phenylene bismaleimide, N,N'-p-phenylene bismaleimide, N,N'-m-stilbene bismaleimide, 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 Leimide, N,N'-4,4-diphenylmethane bismaleimide, N,N'-4,4-diphenylpropane bismaleimide, N,N'- 3,3'-diphenylsulfone bismaleimide, N,N'-4,4-diphenyl ether bismaleimide, 2,2-bis(4-(4-maleimide Iminophenoxy)phenyl)propane, 2,2-bis(3-tert-butyl-4,8-(4-maleimidephenoxy)phenyl)propane, 1,1-bis( 4-(4-maleimidephenoxy)phenyl)decane, 4,4'-cyclohexylene-bis(1-(4-maleimidephenoxy)-2-cyclohexyl Benzene and 2,2-bis(4-(4-maleimidephenoxy)phenyl)hexafluoropropane. These may be used alone or in combination of two or more.

The aforementioned citraconimide resin refers to a resin obtained by polymerizing a citraconimide compound having at least one citraconimide group in the molecule. Examples of the citraconimide compound include phenyl citraconimide Amine, 1-methyl-2,4-biscitraconimide benzene, N,N'-m-phenylene bis-citraconimide, N,N'-p-phenylene bis-citraconimide , N,N'-4,4-biphenylene biscitraconimide, N,N'-4,4-(3,3-dimethylbiphenylene) biscitraconimide, N,N'-4,4-(3,3-Dimethyldiphenylmethane)biscitraconimide, N,N'-4,4-(3,3-Diethyldiphenylmethane ) biscitraconimide, N,N'-4,4-diphenylmethane biscitraconimide, N,N'-4,4-diphenylpropane biscitraconimide, N, N'-4,4-diphenyl ether biscitraconimide, N,N'-4,4-diphenylsulfone biscitraconimide, 2,2-bis(4-(4-citraconimide Imidephenoxy)phenyl)propane, 2,2-bis(3-tert-butyl-3,4-(4-citraconimidephenoxy)phenyl)propane, 1,1-bis (4-(4-citraconimidephenoxy)phenyl)decane, 4,4'-cyclohexylene-bis(1-(4-citraconimidephenoxy)phenoxy) -2-cyclohexylbenzene and 2,2-bis(4-(4-citraconimidephenoxy)phenyl)hexafluoropropane. These can be used individually or in combination of 2 or more types.

The above-mentioned nadicimide resin refers to a resin obtained by polymerizing a nadicimide compound having at least one nadicimide group in the molecule. Examples of the nadicimide compound include phenyl nadicimide Amine, 1-methyl-2,4-bis-nadicimide benzene, N,N'-m-phenylene bis-nadicimide, N,N'-p-phenylene-bis-nadicimide , N,N'-4,4-biphenylene bis-nadic imide, N,N'-4,4-(3,3-dimethylbiphenylene) bis-nadic imide, N,N'-4,4-(3,3-Dimethyldiphenylmethane) bis-nadicimide, N,N'-4,4-(3,3-Diethyldiphenylmethane ) bis-nadicimide, N,N'-4,4-diphenylmethane bis-nadicimide, N,N'-4,4-diphenylpropane-bis-nadicimide, N, N'-4,4-diphenyl ether bis-nadic imide, N,N'-4,4-diphenylsulfone bis-nadic imide, 2,2-bis(4-(4-nadic Imidephenoxy)phenyl)propane, 2,2-bis(3-tert-butyl-3,4-(4-nadicimidephenoxy)phenyl)propane, 1,1-bis (4-(4-Nadicimidephenoxy)phenyl)decane, 4,4'-cyclohexylene-bis(1-(4-nadicimidephenoxy)phenoxy) -2-cyclohexylbenzene and 2,2-bis(4-(4-nadicimidephenoxy)phenyl)hexafluoropropane. These can be used individually or in combination of 2 or more types.

The circuit-connecting material 1 may contain other components besides the curing agent generating free radicals and the radically polymerizable substance. For example, thermoplastic resins and thermosetting resins may be contained.

As the thermoplastic resin, polyethylene resin, polyimide resin, polyvinyl chloride resin, polyphenylene ether resin, polyvinyl butyral resin, polyvinyl formal resin, polyamide resin, polyester resin, benzene Oxygen resin, polystyrene resin, xylene resin, polyurethane resin, etc.

As the thermoplastic resin, a hydroxyl-containing resin having a Tg (glass transition temperature) of 40° C. or higher and a molecular weight of 10,000 or higher can be preferably used. For example, a phenoxy resin can be suitably used. Phenoxy resins can be obtained by reacting difunctional phenols with epihalohydrins until they reach a high molecular weight, or by subjecting difunctional epoxy resins to polyaddition reactions with difunctional phenols.

Examples of thermosetting resins include urea resins, melamine resins, phenol resins, xylene resins, epoxy resins, and polyisocyanate resins.

When the above-mentioned thermoplastic resin is contained, it is preferable because handling performance is good and stress relaxation during curing is excellent. In addition, when the above-mentioned thermoplastic resin and thermosetting resin have a functional group such as a hydroxyl group, it is more preferable because the adhesiveness is improved, and it can also be modified with an epoxy group-containing elastomer or a radically polymerizable functional group. Those obtained by modification with a radically polymerizable functional group are preferable because of improved heat resistance.

The weight average molecular weight of the above-mentioned thermoplastic resin is preferably 10,000 or more from the viewpoint of film forming properties, but if it is 1,000,000 or more, the miscibility tends to deteriorate. Here, the weight average molecular weight specified in the present application refers to the weight average molecular weight measured by gel permeation chromatography (GPC) using a calibration curve based on standard polystyrene under the following conditions.

<GPC conditions>

Machine used: Hitachi L-6000 (manufactured by Hitachi, Ltd.)

Chromatographic column: Gelpack GL-R420+Gelpack GL-R430+Gelpack GL-R440 (3 in total) (manufactured by Hitachi Chemical Industries, Ltd.)

Eluent: tetrahydrofuran

Measuring temperature: 40°C

Flow rate: 1.75mL/min

Detector: L-3300RI (manufactured by Hitachi, Ltd.)

In addition, the adhesive composition (resin layer 3 ) may contain an epoxy resin and a latent curing agent instead of a curing agent generating free radicals and a radically polymerizable substance. That is, the circuit connecting material 1 may contain an adhesive composition containing an epoxy resin and a latent curing agent, and conductive particles 8 . When the circuit connecting material 1 is heated, a crosslinked structure is formed in the adhesive composition due to curing of the epoxy resin, and a cured product of the circuit connecting material 1 is formed. In this case, the circuit connecting material 1 functions as an epoxy-curable adhesive.

As epoxy resins, bisphenol-type epoxy resins, which are glycidyl ethers of bisphenols such as bisphenol A, F, and AD, and epoxy novolac resins derived from phenol novolac or cresol novolak are representative epoxy resins. . Other examples include naphthalene-type epoxy resins, glycidylamine-type epoxy resins, glycidyl ester-type epoxy resins, alicyclic epoxy resins, and heterocyclic epoxy resins having a naphthalene skeleton. These can be used alone or in combination of two or more.

Among the above-mentioned epoxy resins, bisphenol-type epoxy resins are preferable because grades with different molecular weights are widely available, and adhesiveness, reactivity, etc. can be set arbitrarily. Among the bisphenol type epoxy resins, bisphenol F type epoxy resins are particularly preferred. Bisphenol F type epoxy resin has a low viscosity, and by using it in combination with a phenoxy resin, the fluidity of the circuit connecting material 1 can be easily set in a wide range. In addition, the bisphenol F type epoxy resin also has an advantage that it is easy to impart good adhesiveness to the circuit connecting material 1 .

In order to prevent electromigration, it is preferable to use an epoxy resin whose concentration of impurity ions (Na ⁺ , Cl ^- , etc.) or hydrolyzable chlorine is 300 ppm or less.

Any latent curing agent may be used as long as it can cure the epoxy resin. In addition, the latent curing agent may be a compound introduced into a crosslinked structure by reacting with the epoxy resin, or may be a catalyst-type curing agent that accelerates the curing reaction of the epoxy resin. It is also possible to use both together.

Examples of the catalyst-type curing agent include anion-polymerizing latent curing agents that promote anionic polymerization of epoxy resins, and cationic-polymerizing latent curing agents that promote cationic polymerization of epoxy resins.

Examples of the anionic polymer latent curing agent include imidazole-based, hydrazide-based, trifluoroboron-amine complexes, aminated imides, polyamine salts, dicyandiamide and modified products thereof. The imidazole-based anionic polymer latent curing agent is formed, for example, by adding imidazole or a derivative thereof to an epoxy resin.

As the cationic polymerization latent curing agent, for example, photosensitive onium salts (aromatic diazonium salts, aromatic sulfonium salts, etc. are mainly used) that cure epoxy resins by irradiation with energy rays are preferable. In addition, there are aliphatic sulfonium salts as substances that are activated by heating to cure the epoxy resin in addition to irradiation with energy rays. Such a curing agent is preferred because of its rapid curing characteristics.

It is preferable to coat these latent curing agents with polyurethane-based, polyester-based polymers, metal thin films such as nickel and copper, and inorganic materials such as calcium silicate to microencapsulate them. This can prolong the usable time.

The compounding quantity of a latent curing agent is preferably 30-60 mass parts with respect to 100 mass parts of epoxy resins, More preferably, it is 40-55 mass parts. When the compounding quantity of a latent curing agent is 30 mass parts or more, the fastening force with respect to the to-be-adhered body by the curing shrinkage of the circuit connecting material 1 will become difficult to fall. As a result, the contact between the conductive particles 8 and the circuit electrodes is maintained, and the connection resistance after the reliability test tends to be easily suppressed. On the other hand, if the compounding amount of the latent curing agent is within 60 parts by mass, the fastening force will not become too strong, so the internal stress in the cured product of the circuit connecting material 1 is unlikely to increase, and there is a tendency to inhibit the adhesive strength. tendency to decrease.

When the circuit connecting material 1 is an epoxy resin adhesive, it is preferable to contain a film forming material. When the liquid is solidified and the constituent composition is made into a film shape, the film-forming material is a film that facilitates the handling of the film and imparts mechanical properties that are not easy to break, crack, and stick. (Normal temperature and normal pressure) can be processed as a film.

As the film forming material, the above-mentioned thermoplastic resins can be used, and phenoxy resins are preferably used from the viewpoint of excellent adhesiveness, compatibility, heat resistance, and mechanical strength.

The phenoxy resin is a resin obtained by reacting difunctional phenols with epihalohydrin until polymerized, or by adding polymerization of difunctional epoxy resins and difunctional phenols. The phenoxy resin can be obtained by, for example, reacting 1 mole of difunctional phenols with 0.985 to 1.015 moles of epihalohydrin in a non-reactive solvent in the presence of a catalyst such as an alkali metal hydroxide at a temperature of 40 to 120°C. get.

In addition, as the phenoxy resin, it is particularly preferable that the compounding equivalent ratio of the difunctional epoxy resin and the difunctional phenol be epoxy group/phenolic hydroxyl group=1/0.9 from the viewpoint of the mechanical properties and thermal properties of the resin. ~1/1.1, in the presence of catalysts such as alkali metal compounds, organophosphorus compounds, cyclic amine compounds, etc., organic compounds such as amides, ethers, ketones, lactones, and alcohols with a boiling point of 120°C or higher It is obtained by heating to 50-200° C. in a solvent under the condition that the reaction solid content is 50% by mass or less, and performing an addition polymerization reaction.

As the bifunctional epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, bisphenol S type epoxy resin can be used. Difunctional phenols are substances having two phenolic hydroxyl groups, and examples thereof include bisphenol compounds such as hydroquinones, bisphenol A, bisphenol F, bisphenol AD, and bisphenol S.

Phenoxy resins can be modified by free radical polymerizable functional groups. The phenoxy resins may be used alone or in combination of two or more.

Furthermore, the circuit connection material 1 may also contain fillers, softening materials, accelerators, anti-aging agents, colorants, flame retardants, thixotropic agents, coupling agents, isocyanates, and the like. When a filler is contained, it is preferable because connection reliability can be improved. The filler can be used as long as the maximum diameter is smaller than the particle diameter of the conductive particles 8, and the compounding amount is preferably in the range of 5 to 60% by volume. If it is 5 to 60 volume%, it will be easy to maintain the effect of improving reliability. As the coupling agent, vinyl-containing substances, acryloyl-containing substances, amino-containing substances, epoxy-group-containing substances, and isocyanate-containing substances are preferable from the viewpoint of improving adhesiveness. Polymerization inhibitors, such as hydroquinone and hydroquinone methyl ethers, can also be used suitably as needed.

The circuit connection material of this embodiment is an adhesive agent for electrically connecting circuit electrodes as mentioned above.

That is, the adhesive of the present embodiment is an adhesive containing an adhesive composition and conductive particles, and the conductive particles have a core formed of a metal having a Vickers hardness of 300 to 1,000 and a surface coated with the core. The outermost layer is formed of a noble metal, and the aggregate particle has an average particle diameter of 5 to 20 μm, and unevenness is formed on the surface of the conductive particle. This adhesive can be used as a circuit connection material for electrically connecting opposing circuit electrodes. Moreover, it can also apply for manufacture of the circuit connection material for electrically connecting opposing circuit electrodes.

In addition, the adhesive of this embodiment is an adhesive containing an adhesive composition and conductive particles, and the conductive particles have a nucleus made of nickel and an outermost layer made of a noble metal covering the surface of the nucleus, In addition, the lumpy particles with an average particle diameter of 5 to 20 μm have irregularities formed on the surface of the conductive particles. This adhesive can be used as a circuit connection material for electrically connecting opposing circuit electrodes. Moreover, it can also apply for manufacture of the circuit connection material for electrically connecting opposing circuit electrodes.

Next, the connection structure of the circuit member of this embodiment using the circuit connection material 1 is demonstrated. The circuit connecting material 1 is suitable for forming a connection structure in which chip components such as semiconductor chips, resistor chips, and capacitor chips, and circuit components having one or more circuit electrodes (connection terminals) such as printed circuit boards are connected to each other.

FIG. 4 is a cross-sectional view showing an embodiment of a connection structure of circuit components. The connection structure 100 of circuit components shown in FIG. 4 includes: a first circuit component 10 with a first circuit substrate 11 and a first circuit electrode 13 formed on its main surface; The second circuit electrode 23 formed on the top, and the second circuit component 20 arranged in a manner that the second circuit electrode 23 faces the first circuit electrode 13; Connection part 1a.

The connection portion 1 a is a cured product formed by curing the circuit connecting material 1 , and contains conductive particles 8 . The connecting portion 1 a bonds the first circuit member 10 and the second circuit member 20 such that the opposing first circuit electrodes 13 and second circuit electrodes 23 are electrically connected. The opposing first circuit electrode 13 and second circuit electrode 23 are electrically connected via conductive particles 8 . Here, even when the connection part 1a does not contain the conductive particle 8, the 1st circuit electrode 13 and the 2nd circuit electrode 23 can be electrically connected via the circuit connection material 1.

The first circuit board 11 is a resin film containing at least one resin selected from the group consisting of polyethylene terephthalate, polyethersulfone, epoxy resin, acrylic resin, and polyimide resin. The first circuit electrode 13 is formed of a material (preferably at least one selected from the group consisting of gold, silver, tin, platinum group metals, and indium-tin oxide) having conductivity to the extent that it can function as an electrode.

The second circuit board 21 is a multilayer wiring board formed of an insulating substrate such as semiconductor chips such as silicon, gallium, arsenic, glass, ceramics, glass/epoxy composite, or plastic. Preferably, the second circuit electrode 23 has a conductor part 23a and a coating film 23b forming a portion of the surface of the circuit electrode 23 in contact with the connection part 1a, and the coating film 23b is electrically connected through the unevenness formed on the surface of the conductive particle 8. As for the conductor portion 23a, the circuit electrode 23 is made of a conductive material (preferably at least one selected from the group consisting of gold, silver, tin, platinum group metals, and indium-tin oxide) that can function as an electrode. a) formation.

The coating film 23b is a coating film formed of a material containing an organic resin, and preferably contains an organic resin such as an imidazole compound. The film 23 b is formed by subjecting the second circuit board 21 to an OSP (Organic Solderability Preservative: Organic Solderability Preservative) treatment. Here, the OSP treatment refers to a substrate treatment method also called a water-soluble preflux, and generally, an OSP film is formed by treating a substrate with a solution containing an imidazole compound. The film containing an imidazole compound refers to a film formed by bonding a complex of an imidazole derivative and a metal to each other on the electrode surface. That is, the film containing an imidazole compound can be formed by performing OSP treatment with a solution containing an imidazole compound on a substrate on which circuit electrodes are formed. As the imidazole compound, a benzimidazole derivative is suitably used from the viewpoint of heat resistance. OSP treatment can use, for example, Shikoku Chemicals Co., Ltd.'s trade name タフエース F2, F2 (LX) manufactured by Shikoku Kasei Co., Ltd., or Docot GVII manufactured by Sanwa Research Institute, or Entek 106A, 106A (X) manufactured by Enthone Corporation. or Mec seal CL-5824S, CL-5018, or CL-5018S manufactured by Mec Co., Ltd.

In the circuit connection material according to the present embodiment, at least one of the first circuit electrode and the second circuit electrode can be used for connection of a circuit member having a film formed of a material containing an organic resin. Here, as shown in FIG. 5, it is a cross-sectional view showing one embodiment of the connection structure of circuit components. Preferably, not only the second circuit electrode 23, but also the first circuit electrode 13 may have a conductor portion 13a and form the surface of the circuit electrode 13. The coating film 13b of the portion in contact with the connection portion 1a is also electrically connected to the coating film 13b of the first circuit electrode 13 through the unevenness formed on the surface of the conductive particle 8 . The coating film 13b is formed by the same method as the coating film 23b.

The manufacturing method of the connection structure of the circuit component of this embodiment includes the following steps: the first circuit component with the first circuit electrode formed on the main surface of the first circuit substrate and the first circuit component with the first circuit electrode formed on the main surface of the second circuit substrate. The second circuit member of the two circuit electrodes is arranged in such a manner that the first circuit electrode and the second circuit electrode face each other, and the film-shaped circuit connecting material of this embodiment is interposed between the first circuit electrode and the second circuit electrode arranged oppositely. In a state where the whole is heated and pressurized, the first circuit member and the second circuit member are connected so that the first circuit electrode and the second circuit electrode are electrically connected.

The connection structure 100 of circuit components is obtained by the following manufacturing method, that is, for example, the first circuit component 10, the above-mentioned film-like circuit connecting material 1 and the second circuit component 20 are connected in this order with the first circuit electrode 13 and the second circuit electrode 13. The laminate in which the electrodes 23 face each other is heated and pressed to connect the first circuit member 10 and the second circuit member 20 so that the first circuit electrode 13 and the second circuit electrode 23 are electrically connected.

In this manufacturing method, for example, in a state where the film-like circuit-connecting material 1 formed on the support film is attached to the second circuit member 20, heat and pressure are applied to temporarily adhere the circuit-connecting material 1, and the support film can be peeled off. Thereafter, the first circuit member 10 is aligned and placed so that the circuit electrodes face each other, thereby preparing a laminate. In order to prevent the connection from being affected by volatile components generated by heating during connection, it is preferable to heat-treat the circuit components before the connection step.

The conditions for heating and pressurizing the above-mentioned laminate are appropriately adjusted according to the curability of the composition in the circuit connecting material, etc. so that the circuit connecting material is cured and sufficient adhesive strength is obtained. In addition, connection by light irradiation is also possible depending on the composition in the circuit connecting material.

The substrates of the circuit components constituting the connection structure may be semiconductor chips such as silicon, gallium, or arsenic, and insulating substrates such as glass, ceramics, glass/epoxy composites, and plastics.

Example

Hereinafter, the contents of the present invention will be described more concretely using examples. However, the present invention is not limited to these Examples.

(1) Production of circuit connection materials

(1-1) Preparation of each component constituting the adhesive composition

"PERHEXA 25O": 2,5-Dimethyl-2,5-bis(2-ethylhexanoyl)hexane (manufactured by NOF, trade name)

"UN5500": Urethane acrylate oligomer (manufactured by Negami Industry, trade name)

"DCP-A": Dicyclopentadiene-type diacrylate (manufactured by Toagosei, trade name)

"M-215": Isocyanuric acid EO modified diacrylate (manufactured by Toagosei, trade name)

"P-2M": 2-Methacryloyloxyethyl acid phosphate (manufactured by Kyoeisha Chemical Co., Ltd., trade name)

"HX3941HP": Epoxy resin containing anionic polymerization type latent curing agent (contains 35% by mass of imidazole-based microcapsule type curing agent, manufactured by Asahi Kasei Chemicals, trade name)

"UR-8200": polyester polyurethane (manufactured by Toyobo, trade name)

"EV40W": Ethylene-vinyl acetate copolymer (manufactured by Mitsui DuPont Polychemicals, trade name)

"PKHC": Bisphenol A type phenoxy resin (weight average molecular weight 45000, manufactured by INCHEM CORPORATION, trade name)

"Acrylic rubber A": a copolymer of 40 parts by mass of butyl acrylate - 30 parts by mass of ethyl acrylate - 30 parts by mass of acrylonitrile - 3 parts by mass of glycidyl methacrylate (weight average molecular weight about 850,000)

"SH6040": Silane coupling agent (γ-glycidyloxypropyltrimethoxysilane, manufactured by Toray Dow Corning Silicones, trade name)

(1-2) Preparation of conductive particles

As "conductive particle A", a conductive particle with an average particle diameter of 10 μm was prepared, which had a core body formed of Ni particles having a plurality of irregularities formed on the surface, and an outermost layer made of gold formed by plating the core body with gold. particle. As the "conductive particle B", a core body formed of Ni particles having a plurality of irregularities formed on the surface and an outermost layer made of palladium formed by performing palladium plating on the core body were prepared, and an average particle diameter of 10 μm was prepared. conductive particles. Moreover, as "conductive particle C", the conductive particle which has the core body which consists of a spherical Ni particle, and the outermost layer which consists of gold which plated this core body with gold, and has an average particle diameter of 10 micrometers was prepared. As "conductive particle D", the conductive particle which has the core body which consists of a spherical Ni particle, and the outermost layer which consists of gold which plated this core body and formed, and has an average particle diameter of 10 micrometers was prepared. Moreover, as "conductive particle E", the conductive particle which has only the nucleus which consists of the Ni particle which formed the unevenness|corrugation on the surface, and has an average particle diameter of 10 micrometers was prepared. As "conductive particle F", the conductive particle which has only the nucleus which is a spherical Ni particle and has an average particle diameter of 10 micrometers was prepared. Here, the nuclei formed by Ni particles having a plurality of irregularities formed on the surface are formed by reacting nickel ore and carbon monoxide at 25°C to form a nickel carbonyl complex, and heating the nickel carbonyl complex at 100°C to release From the (carbonyl method), so as to obtain.

(Example 1)

8 parts by mass of a 50 mass % hydrocarbon solvent solution of "PERHEXA 25O" (4 parts by mass in terms of non-volatile components), 60 parts by mass of a 50 mass % toluene solution of "UN5500" as a radical polymerizable substance (calculated as a non-volatile component) 30 parts by mass in terms of volatile components), 8 parts by mass of "DCP-A", 8 parts by mass of "M-215", 2 parts by mass of "P-2M", 30 parts by mass of "UR-8200" 150 parts by mass of a ketone/toluene (=50/50) solution (45 parts by mass in terms of non-volatile components) and 50 parts by mass of a 20 mass % toluene solution of "EV40W" (10 parts by mass in terms of non-volatile components), Furthermore, 10 parts by mass of "conductive particles A" were blended. This mixed solution was coated on a PET film with a coater, and dried with hot air at 70° C. for 10 minutes to obtain a film-form circuit connecting material with a resin layer thickness of 35 μm.

(Example 2)

Except having used 10 mass parts of electroconductive particles B as an electroconductive particle, it carried out similarly to Example 1, and obtained the film-form circuit connection material.

(Example 3)

Except having used 20 mass parts of electroconductive particles A as electroconductive particles, it carried out similarly to Example 1, and obtained the film-form circuit connection material.

(Example 4)

Mix 50 parts by mass of "HX3941HP-SS", 37.5 parts by mass of a 40 mass% toluene/ethyl acetate (=50/50) solution of "PKHC" (15 parts by mass in terms of non-volatile components), "acrylic rubber A" 350 parts by mass of a 10 mass % toluene/ethyl acetate (=50/50) solution (35 parts by mass in terms of non-volatile components) and 2 parts by mass of "SH6040", and further, 10 parts by mass of "conductive particle A" . This mixed solution was coated on a PET film with a coater, and dried with hot air at 70° C. for 10 minutes to obtain a film-like circuit connecting material having a resin layer thickness of 35 μm.

(Example 5)

Except having used 10 mass parts of electroconductive particles B as an electroconductive particle, it carried out similarly to Example 4, and obtained the film-form circuit connection material.

(Example 6)

Except having used 20 mass parts of electroconductive particles A as electroconductive particles, it carried out similarly to Example 4, and obtained the film-form circuit connection material.

(comparative example 1)

Except having used 10 mass parts of electroconductive particles C as an electroconductive particle, it carried out similarly to Example 1, and obtained the film-form circuit connection material.

(comparative example 2)

Except having used 10 mass parts of electroconductive particles D as electroconductive particle, it carried out similarly to Example 1, and obtained the film-form circuit connection material.

(comparative example 3)

Except having used 10 mass parts of electroconductive particles E as electroconductive particle, it carried out similarly to Example 1, and obtained the film-form circuit connection material.

(comparative example 4)

Except having used 10 mass parts of electroconductive particles F as electroconductive particle, it carried out similarly to Example 1, and obtained the film-form circuit connection material.

(comparative example 5)

Except having used 10 mass parts of electroconductive particles C as an electroconductive particle, it carried out similarly to Example 4, and obtained the film-form circuit connection material.

(comparative example 6)

Except having used 10 mass parts of electroconductive particles D as an electroconductive particle, it carried out similarly to Example 4, and obtained the film-form circuit connection material.

(comparative example 7)

Except having used 10 mass parts of electroconductive particles E as an electroconductive particle, it carried out similarly to Example 4, and obtained the film-form circuit connection material.

(comparative example 8)

Except having used 10 mass parts of electroconductive particles F as electroconductive particle, it carried out similarly to Example 4, and obtained the film-form circuit connection material.

The composition of the circuit connection material of Examples 1-6 and Comparative Examples 1-8 is shown in Table 1 and Table 2 by mass parts (non-volatile matter conversion).

【Table 1】

【Table 2】

(2) Fabrication of connection structure of circuit components

(2-1) Manufacture of OSP-treated printed circuit board (PWB)

Copper circuit electrodes (hereinafter referred to as "PWB") having a line width of 100 µm, a pitch of 400 µm, and a thickness of 35 µm were formed on a glass/epoxy multilayer printed circuit board. Further, OSP treatment was carried out on the surface of the copper circuit electrode of the PWB using a benzimidazole compound (manufactured by Shikoku Chemicals Co., Ltd., trade name "tafues") to form a film of a benzimidazole-based resin complex with a thickness of 0.10 to 0.32 μm (hereinafter call it "OSP-PWB").

(2-2) Manufacture of OSP-treated flexible printed circuit board (FPC)

A flexible printed circuit board (hereinafter referred to as "FPC") in which copper circuit electrodes with a line width of 100 μm, a pitch of 400 μm, and a thickness of 18 μm were directly formed on a polyimide film with a thickness of 25 μm was prepared. This was subjected to OSP treatment in the same manner as the aforementioned OSP-PWB to form a benzimidazole-based resin complex substrate with a thickness of 0.10 to 0.32 μm (hereinafter referred to as “OSP-FPC”).

(2-3) Connection of circuit electrodes (connection between PWB and FPC)

Before connection, OSP-PWB and OSP-FPC were subjected to heat treatment on a hot plate at 250° C. for 30 seconds as a simulated process in a reflow oven. On the OSP-PWB, after affixing the adhesive surface of the said film-form circuit connection material, it heated and pressurized at 70 degreeC and 1 MPa for 2 second, and temporarily connected, and peeled off the PET film after that. Next, after aligning so that the circuit electrode of OSP-FPC and the circuit electrode of OSP-PWB might face each other, it heated and pressurized at 160 degreeC and 4 MPa for 6 second about Examples 1-3 and Comparative Examples 1-4. Moreover, it heated for 20 second at 170 degreeC and 4 MPa about Examples 4-6 and Comparative Examples 5-8. The width between the substrates of the FPC and the PWB is 2mm.

(3) Evaluation of the connection structure of circuit components

(3-1) Measurement of connection resistance

The resistance value between the circuits including the circuit connection part of the produced connection structure was measured by the four-terminal method using a digital multimeter. The connection resistance is measured after the high temperature and high humidity treatment in a constant temperature and humidity chamber at 85°C and 85% RH for 1,000 hours immediately after connection, and after 1,000 cycles of thermal shock tests at -40°C to +100°C were measured after treatment. The connection resistance measured by the four-probe method after the reliability test was judged to be good in the range of 100 mΩ or less. The results are shown in Table 3.

【table 3】

As shown in Table 3, it was confirmed that the circuit connection materials of Examples 1 to 6 had a small increase in connection resistance after the high-temperature, high-humidity treatment and after the thermal shock test, and were excellent in connection reliability. On the other hand, the circuit connection materials of Comparative Examples 1 to 8 showed a connection resistance exceeding 100 mΩ after the high-temperature, high-humidity treatment and after the thermal shock test, and were poor in connection reliability.

Industrial Applicability

Utilizing the present invention, it is possible to provide a circuit connection material, a circuit component connection structure, and a circuit component connection structure that can be cured in a short time and impart high connection reliability when used on an OSP-treated substrate method.

Explanation of reference signs

1-circuit connection material; 1a-connection portion; 3-resin layer; 8-conductive particles; 10-first circuit component; 11-first circuit substrate; 13-first circuit electrode; 20-second circuit component; 21 - second circuit board; 23 - second circuit electrode; 23a - conductor part; 23b - film; 100 - connection structure of circuit components.

Claims (21)

1. A circuit connection material characterized in that it is a circuit connection material for electrically connecting opposing circuit electrodes to each other, Contains an adhesive composition and conductive particles, The conductive particles are lumpy particles having a core formed of a metal with a Vickers hardness of 300 to 1000 and an outermost layer formed of a noble metal covering the surface of the core, and having an average particle diameter of 5 to 20 μm. The surface of the conductive particle is formed with irregularities. 2. A circuit connection material characterized in that it is a circuit connection material for electrically connecting opposing circuit electrodes to each other, Contains an adhesive composition and conductive particles, The conductive particles are lumpy particles having a nucleus formed of nickel and an outermost layer formed of a noble metal covering the surface of the nucleus, and have an average particle diameter of 5 to 20 μm, and unevenness is formed on the surface of the conductive particle. . 3. The circuit connecting material according to claim 1 or 2, wherein the height difference of the unevenness is 70 nm to 2 μm. 4. The circuit connecting material according to any one of claims 1 to 3, wherein the adhesive composition contains a radical polymerizable substance and a curing agent that generates free radicals by heating. 5 . The circuit connecting material according to claim 1 , wherein the adhesive composition contains an epoxy resin and a latent curing agent. 6 . The circuit connecting material according to claim 1 , wherein at least one of the opposing circuit electrodes has a film containing an imidazole compound. 7. A connection structure of circuit components, characterized in that it has: a first circuit component having a first circuit electrode formed on the principal surface of the first circuit substrate; A second circuit component in which a second circuit electrode is formed on the main surface of the second circuit substrate, and the second circuit electrode is arranged to face the first circuit electrode; provided between the first circuit board and the second circuit board, and connect the first circuit part and the second circuit part so that the first circuit electrode and the second circuit electrode are electrically connected circuit connection part, The said circuit connection part is the hardened|cured material of the film-form circuit connection material in any one of Claims 1-6. 8. The connection structure according to claim 7, wherein at least one of the first circuit electrode and the second circuit electrode has a film containing an imidazole compound. 9. A method for manufacturing a connection structure of circuit components, comprising the following steps: A first circuit component having a first circuit electrode formed on a main surface of a first circuit substrate and a second circuit component having a second circuit electrode formed on a main surface of a second circuit substrate are separated by the first circuit electrode and the second circuit component. The second circuit electrodes are arranged so as to face each other, so that the film-form circuit connecting material according to any one of claims 1 to 6 is interposed between the first circuit electrodes and the second circuit electrodes arranged opposite to each other. The state of heating and pressurizing the whole, connecting the first circuit member and the second circuit member so that the first circuit electrode and the second circuit electrode are electrically connected. 10. Use of an adhesive as a circuit connection material for electrically connecting opposite circuit electrodes to each other, characterized in that, The adhesive contains an adhesive composition and conductive particles, The conductive particles are lumpy particles having a core formed of a metal with a Vickers hardness of 300 to 1000 and an outermost layer formed of a noble metal covering the surface of the core, and having an average particle diameter of 5 to 20 μm. The surface of the conductive particle is formed with irregularities. 11. Use of an adhesive as a circuit connection material for electrically connecting opposite circuit electrodes to each other, characterized in that, The adhesive contains an adhesive composition and conductive particles, The conductive particles are lumpy particles having a nucleus formed of nickel and an outermost layer formed of a noble metal covering the surface of the nucleus, and have an average particle diameter of 5 to 20 μm, and unevenness is formed on the surface of the conductive particle. . 12. The application according to claim 10 or 11, characterized in that the height difference of the unevenness is 70nm-2μm. 13. The application according to any one of claims 10 to 12, wherein the adhesive composition contains a radically polymerizable substance and a curing agent that generates free radicals by heating. 14. The use according to any one of claims 10-12, characterized in that the adhesive composition contains epoxy resin and latent curing agent. 15. The use according to any one of claims 10 to 14, wherein at least one of the first circuit electrode and the second circuit electrode has a film containing an imidazole compound. 16. Use of an adhesive in the manufacture of a circuit connection material for electrically connecting opposing circuit electrodes to each other, characterized in that, The adhesive contains an adhesive composition and conductive particles, The conductive particles are lumpy particles having a core formed of a metal with a Vickers hardness of 300 to 1000 and an outermost layer formed of a noble metal covering the surface of the core, and having an average particle diameter of 5 to 20 μm. The surface of the conductive particle is formed with irregularities. 17. Use of an adhesive in the manufacture of a circuit connection material for electrically connecting opposing circuit electrodes to each other, characterized in that, The adhesive contains an adhesive composition and conductive particles, The conductive particles are lumpy particles having a nucleus formed of nickel and an outermost layer formed of a noble metal covering the surface of the nucleus, and have an average particle diameter of 5 to 20 μm, and unevenness is formed on the surface of the conductive particle. . 18. The application according to claim 16 or 17, characterized in that the height difference of the unevenness is 70nm-2μm. 19. The use according to any one of claims 16-18, characterized in that the adhesive composition contains a radically polymerizable substance and a curing agent that generates free radicals by heating. 20. The use according to any one of claims 16-18, characterized in that the adhesive composition contains epoxy resin and latent curing agent. 21. The use according to any one of claims 16 to 20, wherein at least one of the first circuit electrode and the second circuit electrode has a film containing an imidazole compound.