KR100484383B1 - Anisotropic conductive adhesives for connecting circuit, and connecting method of circuit board and circuit connected structure material using the same - Google Patents

Abstract

The present invention provides an anisotropic conductive circuit connection adhesive which presses a substrate having circuit electrodes facing each other by interposing between substrates having circuit electrodes facing each other, and electrically connects the electrodes in the pressing direction. An adhesive for anisotropic conductive circuit connection comprising a conductive polymer surface-treated with at least one compound selected from the group consisting of a radically polymerizable compound and (2) a basic compound and a compound having at least one epoxy group, Disclosed are a circuit board connecting method and a circuit connecting structure using the same.

Description

Anisotropic conductive adhesives for connecting circuit, and connecting method of circuit board and circuit connected structure material using the same}

The present invention relates to an anisotropic conductive circuit connection adhesive, a circuit board connection method and a circuit connection structure using the same, and more particularly, for anisotropic conductive circuit connection having excellent low temperature fast curing properties and good storage stability and stable connection resistance. A connection method and a bonded structure of an adhesive agent and a circuit board using the same.

Background Art In recent years, various adhesive materials have been used for fixing electronic components or making circuit connections in fields such as semiconductors and liquid crystal displays. Higher density and higher definition progress as these uses progress, and high adhesive force and reliability are calculated | required also for an adhesive agent.

In particular, an adhesive for anisotropic conductive circuit connection in which conductive particles are dispersed in an adhesive is used for the connection between the liquid crystal display and the TCP or the FPC and the TCP, and the connection between the FPC and the printed wiring board as the circuit connection material. In recent years, even when the semiconductor silicon chip is mounted on a substrate, so-called flip chip mounting is performed in which a semiconductor silicon chip is directly mounted on the substrate instead of a conventional wire bond face down. In addition, the use of the adhesive agent for anisotropic conductive circuit connection is also disclosed here (JP-A-59-120436, JP-A-60-191228, JP-A- 1-251787, and JP-A-7-90237).

In recent years, in the field of precision electronic devices, circuit densification has been progressed, and electrode width and electrode spacing have become very narrow. For this reason, the connection conditions of the adhesive agent for circuit connection using the conventional epoxy resin system had the problem of a wiring | wire falling off, peeling, and a position difference. In addition, the shortening of the connection time has been strongly demanded for the connection of less than 10 seconds in order to improve the production efficiency, and low temperature fast curing is indispensable. Therefore, Japanese Patent Laid-Open No. 10-273636 discloses a circuit connection material using a radical polymerizable material.

However, when the adhesive containing radical polymerizable substances, such as a (meth) acrylate and a phosphate ester compound, and an electrically-conductive particle is left in air, there exists a problem that the connection resistance at the time of connection increases.

The present invention has excellent low temperature fast curing property and good storage stability, and has a stable connection resistance. An adhesive for anisotropic conductive circuit connection excellent in pot life under high temperature conditions, and a circuit board connection method using the same. And providing a connection structure.

The present invention relates to an anisotropic conductive circuit connection adhesive, comprising a resin film-form formed by uniformly spraying conductive particles, and comprising at least the following components.

(1) conductive particles having no transition metal other than Ag, Au, or Pt exposed on their surface;

(2) radically polymerizable materials,

(3) A curing agent that generates free radicals by heating or light.

The present invention also relates to an adhesive for anisotropic conductive circuit connection, comprising a resin film-form formed by uniformly dispersing conductive particles, and comprising at least the following components.

(1) conductive particles having no transition metal other than Ag, Au, or Pt exposed on their surface;

(2) radically polymerizable materials,

(3) a curing agent that generates free radicals by heating or light, and

(4) Phosphate ester compound.

The present invention further provides an anisotropic conductive circuit connection adhesive interposed between substrates having circuit electrodes opposing each other, pressurizing the substrates having opposing circuit electrodes, and irradiating light (active energy) in some cases. And a circuit board connecting method for electrically connecting the electrodes in the pressing direction.

The present invention also relates to a connection structure in which the anisotropic conductive circuit connection adhesive is interposed between substrates having circuit electrodes facing each other, and the substrates having circuit electrodes facing each other are pressed to electrically connect the electrodes in the pressing direction. It is about.

Even if the adhesive for anisotropic conductive circuit connection of the present invention is left at room temperature and high humidity, an increase in connection resistance and a decrease in adhesive strength are suppressed even after various reliability tests such as initial connection, moisture resistance test, and cold cycle, and exhibit excellent connection reliability.

The adhesive agent for anisotropic conductive circuit connection is an anisotropic conductive resin formed in the film and the to-be-adhered body surface.

The present invention also provides an adhesive for anisotropic conductive circuit connection, which is interposed between substrates having opposite circuit electrodes and pressurizes substrates having opposite circuit electrodes to electrically connect the electrodes in the pressing direction. An adhesive for anisotropic conductive circuit connection, comprising: conductive particles surface-treated with at least one compound selected from the group consisting of: a radically polymerizable compound and (2) a basic compound and a compound having at least one epoxy group. It is about. It is preferable that the said adhesive agent for anisotropic conductive circuit connections contains the compound which generate | occur | produces a radical by light or heating, or the phosphate ester compound. Moreover, it is preferable that the basic compound used for surface treatment of the adhesive agent for anisotropic conductive circuit connections of this invention is an amino compound.

In still another aspect of the present invention, an anisotropic conductive circuit connection adhesive is interposed between substrates having opposing circuit electrodes, and the substrates having opposing circuit electrodes are pressed to electrically connect the electrodes in the pressing direction. The conductive particles having a connection structure, wherein the adhesive for anisotropic conductive circuit connection is surface treated with at least one compound selected from the group consisting of (1) a radically polymerizable compound and (2) a basic compound and a compound having at least one epoxy group. It relates to an anisotropic conductive circuit connection structure which is an adhesive.

In the adhesive agent for anisotropic conductive circuit connections of this invention, the electroconductive particle which does not expose transition metals, such as Ni, other than Ag, Au, and Pt, to the surface of electroconductive particle is used. In order to obtain sufficient moisture resistance pot life and connection reliability, the metal on the surface becomes Au, Ag, platinum group precious metals, and Au is more preferable.

The conductive particles used for the anisotropic conductive circuit connection adhesive of the present invention are not particularly limited as long as they have conductivity capable of obtaining electrical connection, but metal particles such as Au, Ag, Ni, Cu, Co, and lead, carbon, and the like can be cited. Can be. Moreover, the thing which coat | covered non-conductive glass, ceramic, plastics, etc. with the electrically conductive material of the said metal can also be used. At this time, in order to acquire sufficient electroconductivity, the thickness of the metal layer to coat | cover is 100 Pa or less is preferable. When a precious metal layer is provided on transition metals such as Co, Zn, Cu, and Ni, free radicals are generated by redox action caused by defects in the precious metal layer or defects in the precious metal layer caused by mixed dispersion of conductive particles. The conductive particles are surface treated because they cause a decrease in pot life. The conductive particles are used in the range of 0.1 to 30% by volume with respect to the adhesive component for circuit connection, and preferably in the range of 0.1 to 20% by volume.

It is preferable to treat it with a compound having reactivity with an acidic substance as a compound for treating the surface of the conductive particles, and by this treatment, the storage stability of the adhesive for anisotropic conductive circuit connection can be remarkably improved.

As the compound for treating the surface of the conductive particles, a compound having a basic compound or at least one epoxy group is preferable, and an amino compound is particularly preferable as the basic compound.

The amino compound may be a liquid or a solid, and in the case of a solid, it is used after being dissolved in an organic solvent, water, or the like. Moreover, also in a liquid compound, it is preferable to melt | dissolve and use for an organic solvent. The organic solvent is not particularly limited as long as the amino compound is dissolved without reactivity with the amino compound. However, methanol, ethanol, isopropanol, methyl ethyl ketone, ethyl acetate, toluene and the like are preferable in terms of drying the conductive particles after treatment.

As a density | concentration of the amino compound contained in a process liquid, 0.05-20 weight% is preferable. If the amount is less than 0.05% by weight, the surface treatment is not effectively performed. If the amount is more than 20% by weight, the amount of the amino compound to be coated on the surface of the conductive particles increases, resulting in high connection resistance.

The compound having at least one epoxy group may be a liquid or a solid, and in the case of a solid, it is used after being dissolved in an organic solvent, water, or the like. Moreover, also in a liquid compound, it is preferable to melt | dissolve and use for an organic solvent. The organic solvent is not particularly limited as long as the compound having at least one epoxy group is dissolved without reactivity with the compound having at least one epoxy group, but methanol, ethanol, isopropanol, methyl ethyl ketone, ethyl acetate, toluene and the like are conductive particles after surface treatment. It is preferable at the point which dries.

As a density | concentration of the compound which has at least 1 epoxy group contained in a process liquid, 0.05-20 weight% is preferable. If it is less than 0.05 weight%, surface treatment will not be performed effectively. If it exceeds 20 weight%, the quantity of the compound which has at least 1 epoxy group coat | covered on the surface of a conductive particle will become large, and connection resistance will become high.

Although the processing conditions, such as temperature and time in the case of surface treatment, do not have a restriction | limiting in particular, It is preferable that processing temperature is the range of room temperature (25 degreeC)-100 degreeC, and processing time is 10 second-1 hour.

The treated conductive particles are dried after filtration and used. Drying conditions are appropriately selected depending on the organic solvent used, but are carried out at room temperature (25 ° C) to 150 ° C.

As a basic compound used for the surface treatment of this invention, ie, an amino compound, triethylamine, diethylamine, butylamine, ethylenediamine, hexamethyldiamine, aniline, aminopropyltrimethoxysilane, imidazole, 2-ethyl- 4-methylimidazole, 2-phenyl-1-cyanoethylimidazole, vinylimidazole, vinylpyridine, and the like. Examples of the amine type include primary, secondary and tertiary amines. You may use these 2 or more types in mixture.

As a compound which has at least 1 epoxy group used for surface treatment in this invention, phenyl glycidyl ether, glycidyl (meth) acrylate, (gamma)-glycidoxy propyl trimethoxysilane, (gamma)-glycidoxy propyl methyl tri Ethoxysilane, (gamma)-glycidoxy propylmethyldimethoxysilane, (gamma) -glycioxy propylmethylethoxysilane, (beta)-(3, 4- epoxycyclohexyl) ethyltrimethoxysilane, bisphenol-A epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol no block type epoxy resin, cresol no block type epoxy resin, bisphenol A no block type epoxy resin, bisphenol F no block type epoxy resin, alicyclic epoxy resin, glycidyl ester type epoxy resin, Glycidyl amine epoxy resins, hydantoin epoxy resins, isocyanate epoxy resins, and epoxy resins on aliphatic chains. These epoxy resins may be halogenated. , It may be hydrogenated. These epoxy compounds may use 2 or more types together.

The radically polymerizable compound used for the adhesive for anisotropic conductive circuit connections of the present invention is a compound having a functional group which is polymerized by radicals, and (meth) acrylate resin, maleimide resin, citraconimide resin, nadiimide resin, and the like. You may mix and use two or more types. Moreover, a radically polymerizable compound can be used also in the state of a monomer and an oligomer, and you may use it, mixing a monomer and an oligomer. Here, "(meth) acrylate" means an acrylate and the methacrylate corresponding to it.

As (meth) acrylate resin, it is obtained by radically polymerizing (meth) acrylate. As (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, Isobutyl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylene glycol tetra (meth) acrylate, 2-hydrate Oxy-1,3-diacryloxypropane, 2,2-bis [4- (acryloxymethoxy) phenyl] propane, 2,2-bis [4- (acryloxyethoxy) phenyl] propane, dicyclophene Tenyl (meth) acrylate, tricyclodecanyl (meth) acrylate, tris (acryloxyethyl) isocyanate, urethane (meth) acrylate, isocyanurate ethylene oxide modified diacrylate, and the like, 2 may be mixed with a more thereof. If necessary, radical polymerization inhibitors such as hydrokinone and methyl ether hydrokinone may be used in a range where the curability is not impaired.

Moreover, when a phosphate ester compound is used as a radically polymerizable compound, the adhesive force with respect to inorganic substances, such as a metal, can be improved. The usage-amount of this phosphate ester compound is 0.1-10 weight part with respect to 100 weight part of adhesive components, Preferably it is 0.5-5 weight part. A phosphate ester compound is obtained as a reaction product of phosphoric anhydride and 2-hydroxyethyl (meth) acrylate. Specific examples thereof include mono (2-methacrylooxyethyl) acid phosphate and di (2-methacryloyloxyethyl) acid phosphate, and may be used alone or in combination.

The maleimide resin has at least one maleimide group in the molecule, such as phenylmaleimide, 1-methyl-2,4-bismaleimide benzene, N, N'-m-phenylenebismaleimide, N, N '-p-phenylenebismaleimide, N, N'-4,4-biphenylenebismaleimide, 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-diphenylmethanebismaleimide, N, N'-4,4-diphenylpropanebismaleimide, N, N'-4,4-diphenyletherbismaleimide, N, N'-4 , 4-diphenylsulfonbismaleimide, 2,2-bis (4- (4-maleimidephenoxy) phenyl) propane, 2,2-bis (3-s-butyl-3,4- (4-maleic Midphenoxy) phenyl) propane, 1,1-bis (4- (4-maleimidephenoxy) phenyl) decane, 4,4'-cyclohexylidene-bis (1- (4-maleimidephenoxy) Phenoxy) -2-dicyclohexylbenzene, 2,2-bis (4- (4-maleic) De) phenyl) and the like hexafluoropropane, it may be used either individually or in combination of two or more thereof.

As the citraconimide resin, a citraconimide compound having at least one citraconimide group in a molecule is polymerized. Examples of the citraconimide compound include phenylcitraconimide and 1-methyl-2,4. Biscitraconimide benzene, N, N'-m-phenylenebiscitraconimide, N, N'-p-phenylenebiscitraconimide, 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-diphenylmethanebiscitraconimide, N, N'-4,4-diphenylpropanebiscitraconimide, N, N'-4,4-diphenyletherbiscitraconimide, N, N'-4,4-diphenylsulfonbissheet Laconimide, 2,2-bis (4- (4-citraconimidephenoxy) phenyl) propane, 2,2-bis (3-s-butyl-3,4- (4-citraconimidephenoxy Phenyl) propane , 1,1-bis (4- (4-citraconimidephenoxy) phenyl) decane, 4,4'-cyclohexylidene-bis (1- (4-citraconimidephenoxy) phenoxy) 2-cyclohexyl benzene, 2, 2-bis (4- (4-citraconimide phenoxy) phenyl) hexafluoro propane, etc. may be used individually or in mixture of 2 or more types.

As a nadiimide resin, it polymerized the nadiimide compound which has at least 1 nadiimide group in a molecule | numerator, As a nadiimide compound, For example, Phenylimide, 1-methyl- 2, 4-bisnamidimide benzene, N, N'- m-phenylenebisnamidimide, N, N'-p-phenylenebisnamidimide, N, N'-4,4-biphenylenebisnamidimide, N, N'-4,4- (3,3 -Dimethylbiphenylene) bisnamidimide, N, N'-4,4- (3,3-dimethyldiphenylmethane) bisnamidimide, N, N'-4,4- (3,3-diethyldi Phenylmethane) bisnamidimide, N, N'-4,4-diphenylmethanebisnamidimide, N, N'-4,4-diphenylpropanebisnamidimide, N, N'-4,4-diphenyl Etherbisnamidimide, N, N'-4,4-diphenylsulfonbisnamidimide, 2,2-bis (4- (4-namidimidephenoxy) phenyl) propane, 2,2-bis (3-s -Butyl-3,4- (4-diimidephenoxy) phenyl) propane, 1,1-bis (4- (4-diimidephenoxy) phenyl) decane, 4,4-cyclohexylidene-bis ( 1- (4-nadiiimide (Oxy)) phenoxy) -2-cyclohexylbenzene, 2,2-bis (4- (4-nadiimidphenoxy) phenyl) hexafluoropropane, and the like, or used alone or in combination of two or more thereof. good.

In the case of using the radically polymerizable compound, a polymerization initiator is used as a curing agent for generating free radicals by heating or light. The polymerization initiator is not particularly limited as long as it is a compound that generates radicals by light or heating, and there are peroxides, azo compounds, and the like, and are appropriately selected in consideration of the desired connection temperature, connection time, storage stability, and the like. From the point of storage stability, an organic peroxide having a temperature of 10 hours for a half life of 40 ° C or more and a temperature of 1 minute for a half life of 180 ° C or less is preferred, and a temperature of 50 minutes or more for a half life of 10 hours and a temperature of 1 minute for a half life of 170 Particular preference is given to organic peroxides at or below 캜. When the connection time is 10 seconds, in order to obtain a sufficient reaction rate, the blending amount of the polymerization initiator is preferably 1 to 20% by weight, particularly preferably 2 to 15% by weight based on the total amount of the adhesive. As a specific compound of the organic peroxide to be used, it can be selected from diacyl peroxide, peroxy dicarbonate, peroxy ester, peroxy ketal, dialkyl peroxide, hydroperoxide, and cyryl peroxide, but peroxy ester, dialkyl peroxide Oxides, hydroperoxides and silyl peroxides are particularly preferred because they have 5000 ppm or less of chlorine ions or organic acids in the initiator, few organic acids generated after decomposition, and can suppress corrosion of the connection terminals of the circuit members. It is more preferable to select from the peroxy ester from which high reactivity is obtained. These can be mixed and used by an enemy.

As the diacyl peroxides, isobutyl peroxide, 2,4-dichlorobenzoyl peroxide, 3,5,5, -trimethylhexanoyl peroxide, octanoyl peroxide, lauroyl peroxide, stearoyl peroxide and succinic peroxide , Benzoyl peroxy toluene, benzoyl peroxide and the like.

As peroxydicarbonates, di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, bis (4-t-butylcyclohexyl) peroxydicarbonate, di-2-ethoxymethoxy peroxydicarbonate, di (2 -Ethylhexyl peroxy) dicarbonate, dimethoxy butyl perooxy dicarbonate, di (3-methyl-3- methoxy butyl peroxy) dicarbonate, etc. are mentioned.

As peroxy ester, cumyl peroxy neodecanoate, 1,1,3,3- tetramethylbutyl peroxy neodecanoate, 1-cyclohexyl-1-methylethyl peroxy neodecanoate, t-hex Silperoxyneodecanoate, t-butylperoxy pibarate, 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-ethylhexa Nonate, t-butylperoxy isobutylate, 1,1-bis (t-butylperoxy) cyclohexane, t-hexylperoxyisopropyl monocarbonate, t-butylperoxy-3,5,5-trimethyl Hexanonate, t-butylperoxylaurylate, 2,5-dimethyl-2,5-di (m-toluylperoxy) hexane, t-butylperoxyisopropylmonocarbonate, t-butylperoxy-2 Ethylhexyl monocarbonate, t-hexyl peroxybenzoate, t-butyl peroxy acetate, etc. are mentioned.

As peroxy ketals, 1, 1-bis (t-hexyl peroxy) -3, 3, 5- trimethyl cyclohexane, 1, 1-bis (t-hexyl peroxy) 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.

Examples of the dialkyl peroxides include α, α'-bis (t-butylperoxy) diisopropylbenzene, dicumylperoxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, t- Butyl cumyl peroxide etc. are mentioned.

Diisopropyl benzene hydroperoxide, cumene hydroperoxide, etc. are mentioned as hydroperoxides.

Examples of the silyl peroxides include t-butyltrimethylsilyl peroxide, bis (t-butyl) dimethylsilyl peroxide, t-butyltrivinylsilyl peroxide, bis (t-butyl) divinylsilyl peroxide and tris (t-butyl ) Vinylsilyl peroxide, t-butyl triaryl silyl peroxide, bis (t-butyl) diaryl silyl peroxide, tris (t-butyl) aryl silyl peroxide, etc. are mentioned.

Moreover, in order to suppress corrosion of the connection terminal of a circuit member, it is preferable that chlorine ion and organic acid contained in a free radical generating agent (curing agent) are 5000 ppm or less, and it is more preferable that there are few organic acids which generate | occur | produce after thermal decomposition. Moreover, in order to improve the stability of the produced circuit connection material, it is preferable to have a weight retention rate of 20 weight% or more after opening for 24 hours at room temperature (25 degreeC) and normal pressure. These can be used in admixture.

These free radical generators may be used alone or in combination, or may be used by mixing a decomposition accelerator, an inhibitor and the like.

In addition, it is preferable to coat these free radical generators with a polyurethane-based, polyester-based high molecular material, and the like to microencapsulate them, since the pot life is extended.

In addition to the radically polymerizable compound, an epoxy resin may be blended as the thermosetting resin. Examples of epoxy resins include bisphenol A epoxy resins, bisphenol F epoxy resins, bisphenol S epoxy resins, phenol noblock epoxy resins, cresol noblock epoxy resins, bisphenol A noblock epoxy resins, bisphenol F noblock epoxy resins, and alicyclic epoxy resins. Resins, glycidyl ester type epoxy resins, glycidyl amine type epoxy resins, hydantoin type epoxy resins, isocyanurate type epoxy resins, and epoxy resins on aliphatic chains, and these epoxy resins may be halogenated, Hydrogen may be added. These epoxy resins may use 2 or more types together.

Moreover, as a hard dS agent of the said epoxy resin, what is used as hardening | curing agent of normal epoxy resins, such as amines, phenols, acid anhydrides, imidazoles, and dicyandiamide, is mentioned. In addition, tertiary amines and organophosphorus compounds commonly used as curing accelerators may be suitably used.

Moreover, in addition to using the said hardening | curing agent as a method of making an epoxy resin react, you may carry out cation polymerization using a sulfonium salt, an iodonium salt, etc.

In order to provide the film formation property, adhesiveness, and the reaction relaxation property at the time of hardening, the adhesive agent for circuit connection or the anisotropic conductive resin film form of this invention is polyvinyl butyral resin, polyvinyl formal resin, polyester resin, poly Polymeric components such as amide resin, polyimide resin, xylene resin, phenoxy resin, polyurethane resin, and urea resin are used. These polymer components preferably have a molecular weight of 10,000 to 10,000,000. Moreover, these resin may be modified | denatured by the radically polymerizable functional group, and in this case, heat resistance improves. Moreover, it may be modified | denatured with a radically polymerizable functional group, an epoxy group, a carboxyl group, etc., and heat resistance improves in this case. The compounding quantity of a macromolecular component is 2-80 weight%, 5-70 weight% is preferable and 10-60 weight% is especially preferable. If it is less than 2 weight%, stress relaxation and adhesive force are not enough, and when it exceeds 80 weight%, fluidity will fall.

Appropriate fillers, softeners, accelerators, anti-aging agents, colorants, flame retardants, and coupling agents may be added to the adhesive for anisotropic conductive circuit connections of the present invention.

When it contains a filler, since improvement, such as connection reliability, is obtained, it is preferable. It can be used if the maximum diameter of a filler is less than the particle diameter of a conductive particle, and the range of 5 to 60 volume% is preferable. When it exceeds 60 volume%, the effect of a reliability improvement is saturated. As a coupling agent, a vinyl group, an acryl group, an amino group, an epoxy group, an azide group, and a non-isocyanate group containing material are preferable at the point of an adhesive improvement.

Moreover, you may make it the multilayer structure which consists of two or more types of layers in which Tg (glass transition temperature) when the adhesive for anisotropic conductive circuit connections of this invention is made into hardened | cured material.

The substrate to be bonded using the anisotropic conductive circuit connection adhesive of the present invention is not particularly limited as long as an electrode that requires electrical connection is formed, but a glass or plastic substrate having an electrode formed on an ITO or the like used in a liquid crystal display, Image display substrates such as PDP panels and EL panels, printed wiring boards, ceramic wiring boards, flexible wiring boards, semiconductor components such as semiconductor chips, resistor chips, capacitor chips, circuit components such as tape carrier packages, and COF semiconductor silicon chips. Used in combination according to.

There is no restriction | limiting in particular as conditions in the case of a connection, It is connection temperature 90-250 degreeC, connection time 1 second-10 minutes, and it selects suitably according to the use, adhesive agent, and board | substrate to be used. You may post-cure as needed. Although the connection is performed by heating and pressing, energy other than heat, such as light, ultrasonic waves, electromagnetic waves, or the like may be used as necessary.

Hereinafter, although it demonstrates concretely using the Example of this invention, the scope of the present invention is not limited to this Example.

Example 1

50 g of phenoxy resins (manufactured by Union Carbide Co., Ltd., product name PKHC, average molecular weight 45,000) were dissolved in MEK (methyl ethyl ketone, boiling point 79.6 ° C.) to obtain a solution having a solid content of 50% by weight.

Isocyanurate ethylene oxide modified diacrylate (manufactured by Dong-A Synthetic Co., Ltd., brand name M-215) and phosphate ester type acrylate (manufactured by Kogyo Holding Co., Ltd., brand name P-2M) were used as the radical polymerizable material.

 50% by weight hydrocarbon solution of 2,5-dimethyl-2,5-bis (2-ethylhexanoylperoxy) hexane as a curing agent that generates free radicals by heating or light (manufactured by Nippon Oil Holding Co., Ltd., trade name Perhexa 25O) Was used.

As the conductive particles, conductive particles having an average particle diameter of 5 µm in which an Ag layer having a thickness of 0.09 µm were provided on the surface of the particles having a polystyrene as a nucleus (compressive modulus of 480 kg / mm 2) were used.

50 g of phenoxy resin, 50 g of isocyanuric acid ethylene oxide modified diacrylate, 2 g of phosphate ester acrylate, and 5 g of 2,5-dimethyl-2,5-bis (2-ethylhexanoylperoxy) hexane in solid weight ratio 3 vol% of the conductive particles were dispersed and blended, and coated on a PET (polyethylene terephthalate) film having a surface treated with a single surface having a thickness of 80 µm using a pre-processing device, followed by hot air drying at 70 캜 for 10 minutes. This obtained the adhesive agent for anisotropic conductive circuit connections whose thickness of an adhesive bond layer is 35 micrometers.

Example 2

The adhesive for anisotropic conductive circuit connection was carried out in the same manner as in Example 1 using a conductive particle having an average particle size of 6.15 µm in which an Ag layer having a thickness of 0.1 µm was provided on the surface of a polystyrene-based particle (compressive modulus of 366 kg / mm 2). Got it.

Example 3

An average particle diameter of 5 µm in which an Ag layer having a thickness of 0.1 µm is provided on the surface of a polystyrene-based particle (compressive modulus of 480 kg / mm 2) as a conductive particle, and an Au layer having a thickness of 0.04 µm is provided outside the Ag layer. Using the same method as in Example 1, an adhesive for anisotropic conductive circuit connection was obtained.

Example 4

A conductive particle having an average particle diameter of 5 µm in which a Ni layer having a thickness of 0.1 µm is provided on the surface of a polystyrene-derived particle (compressive modulus of 480 kg / mm 2) and an Au layer having a thickness of 0.05 µm is formed outside the Ni layer. Using the same method as in Example 1, an adhesive for anisotropic conductive circuit connection was obtained.

Comparative Example 1

The adhesive for anisotropic conductive circuit connection was carried out in the same manner as in Example 1, using an average particle diameter of 5 µm in which a Ni layer having a thickness of 0.2 µm was formed on the surface of the polystyrene-derived particles (compressive modulus of 480 kg / mm 2) as the conductive particles. Got it.

Comparative Example 2

An average particle diameter of 5 µm in which a Ni layer having a thickness of 0.2 µm was formed on the surface of a polystyrene-based particle (compressive modulus of 480 kg / mm 2) as a conductive particle, and an Au layer having a thickness of 0.04 µm was formed outside the nickel layer. Using the same method as in Example 1, an adhesive for anisotropic conductive circuit connection was obtained.

(Connection of circuit)

Tape Carrier Package (TCP) and ITO Glass (manufactured by Diomatec Co., Ltd., Surface Resistance 20) having 150 copper circuits having a line width of 30 μm, a pitch of 30 μm, and a thickness of 18 μm using the above-described anisotropic conductive resin film-formed product 30 占 Ω / ?, 1.1 mm thick) was pressurized by heating at 140 DEG C and 3 MPa for 15 seconds to obtain a connection structure connected over a width of 2 mm. At this time, after adhering the adhesive surface of the adhesive for anisotropic conductive circuit connection on ITO glass in advance, it heated and pressurized at 80 degreeC and 0.5 MPa for 3 second, and made it half-connection, after that, PET film was peeled off and it connected with TCP.

(Measurement of connection resistance)

The produced anisotropic conductive circuit connection adhesive was stored for 100 hours in -20 ° C storage and 30 ° C and 85% RH constant temperature and humidity chamber, respectively, and then the above circuits were connected to each other and the adjacent circuits of TCP including the connection part were connected. The connection resistance value was measured by multimeter. The connection resistance value is shown as the average of 150 resistance points between adjacent circuits. The measurement results are shown in Table 1.

Table 1

Connection resistance -20 ℃, 100 hours storage 30 ℃, 85% RH, 100 hours storage Example 1 2.1 2.3 Example 2 1.9 2.1 Example 3 2.2 2.4 Example 4 2.3 2.1 Comparative Example 1 2.2 35.5 Comparative Example 2 2.5 28.4

The connection structure obtained in Example 1 exhibited satisfactory connection reliability of 2.5 Ω or less, whether stored at -20 ° C or in a constant temperature and humidity bath at 30 ° C and 85% RH. Similarly, for the bonded structures of Examples 2 and 3, satisfactory connection reliability of 2.5? Or less was obtained either in -20 ° C storage or in a constant temperature and humidity chamber at 30 ° C and 85% RH.

On the other hand, in Comparative Examples 1 and 2, good connection reliability was obtained for the connection structure stored at -20 ° C. However, the connection resistance greatly increased to 10 Ω or more at 30 ° C and 85% RH.

(Measurement of Adhesive Strength)

In Examples 1 to 3, good adhesive strength was obtained at -20 ° C, 30 ° C and 85% RH in a constant temperature and humidity bath at about 1000 N / m. On the other hand, in Comparative Examples 1 and 2, the adhesive strength was about 1000 N / m, which was about 1000 N / m in both the -20 DEG C or 30 DEG C and 85% RH stored in a constant temperature and humidity bath.

(Evaluation of insulation)

Using the obtained adhesive for anisotropic conductive circuit connection, a printed circuit board having a comb-like circuit in which 250 copper circuits having a line width of 50 μm, a pitch of 100 μm, and a thickness of 18 μm were alternately arranged, a line width of 50 μm, a pitch of 100 μm, A Tape Barrier Package (TCP) having 500 copper circuits having a thickness of 18 µm was heated and pressed at 140 ° C and 3 MPa for 15 seconds to connect over a width of 2 mm. A voltage of 100 V was applied to the comb-shaped circuit of this connector, and the insulation resistance value after 500 hours of 85 degreeC and 85% RH high temperature and high humidity test was measured.

In either case, good insulation of 10 ⁹ Ω or more was obtained, and no decrease in insulation was observed.

(Evaluation of liquidity)

The adhesive for anisotropic conductive circuit connections of 35 micrometers in thickness and 5 mm x 5 mm was used, this was sandwiched in glass of thickness 0.7 mm and 15 mm x 15 mm, and heating pressurization was performed at 140 degreeC and 3 MPa for 15 second. When the value of fluidity (B) / (A) was calculated | required using the initial area (A) and the area (B) after heating pressurization, Examples 1-3 were in the range of 1.9-2.0. On the other hand, it was 1.8 and 1.9 also about Comparative Examples 1 and 2.

(Elastic modulus after curing)

It was 1.5 GPa when the elasticity modulus of 40 degreeC after hardening of the adhesive agent for anisotropic conductive circuit connections of Example 1 was measured.

Although the value of the Example of this invention and the value of a comparative example show substantially the same value from the said adhesive strength, insulation, fluidity, and the elasticity modulus after hardening, as shown in Table 1, a connection resistance value differs significantly. Since adhesive strength, insulation, fluidity, and the like exhibit the same characteristics in Examples and Comparative Examples, the coating layer on the surface of the conductive particles is considered to be very thin, but it significantly affects the connection resistance. In the conductive particles in which transition metals other than Ag, Au, and Pt are not exposed on the surface as in the present invention, the polymerization of the radically polymerizable material is not promoted at the surface of the conductive particles, and thus a good value with low connection resistance is exhibited. Even in the case of using a transition metal such as Ni in Example 4, it is excellent in storage stability even when subjected to temperature or temperature and humidity treatment by coating Ag, Au, Pt or the like on the outside of 500 kPa or more and preventing the inner transition metal from being exposed. Connection resistance does not increase.

(Production of Surface Treated Particles A)

In a 1 wt% methanol solution of triethylamine, a nickel layer having a thickness of 0.2 μm was formed on the surface of the polynuclear particles and a gold layer having a thickness of 0.04 μm was provided outside the nickel layer. Particles were added and stirred at 25 ° C for 10 minutes. The conductive particles were filtered off and then dried at 50 ° C. for 15 minutes to obtain surface treated particles A.

(Production of Surface Treated Particles B)

An average particle diameter of 5 μm in which a nickel layer having a thickness of 0.2 μm was provided on the surface of particles made of polystyrene as a nucleus in a 3 wt% methanol solution of aminopropyltrimethoxysilane, and a gold layer having a thickness of 0.04 μm was provided outside the nickel layer. The microparticles | fine-particles were added and stirred for 5 minutes at 50 degreeC. The conductive particles were filtered off and dried at 80 ° C. for 5 minutes to obtain surface treated particles B.

(Production of Surface Treated Particles C)

In a 1% by weight methanol solution of γ-glycidoxy propylmethyldimethoxysilane, a nickel layer having a thickness of 0.2 μm is provided on the surface of particles made of polystyrene as a nucleus, and a gold layer having a thickness of 0.04 μm is provided outside the nickel layer. The electroconductive particle of one average particle diameter of 4 micrometers was added, and it stirred at 25 degreeC for 10 minutes. The conductive particles were filtered off and dried at 50 ° C. for 15 minutes to obtain surface treated particles C.

(Production of Surface Treated Particles D)

An average particle diameter of 5 µm in which a nickel layer having a thickness of 0.2 µm is provided on the surface of the polystyrene-containing particles in a 3 wt% methanol solution of bisphenol A epoxy resin, and a gold layer having a thickness of 0.04 µm is formed outside the nickel layer. Of conductive particles were added and stirred at 50 ° C for 5 minutes. The conductive particles were filtered off and dried at 80 ° C. for 5 minutes to obtain surface treated particles D.

PET (polyethylene terephthalate) which surface-treated the single side | surface of thickness of 50 micrometers using these conductive particles A, B, C, and D, respectively, mix | blending by the following formulation, and using the simple coating machine (made by TESTA INDUSTRIAL CO., LTD.). ) It was apply | coated to a film, and the adhesive agent for circuit connection was produced with the hot air dryer of 70 degreeC and 10 minutes.

Example 5

50 g of phenoxy resins (PKHC, trade name of Union Carbide Co., Ltd., average molecular weight 45,000), 48 g of dicyclohexyl methacrylate and 2 g of phosphate ester acrylate as a radically polymerizable compound, 2,5-dimethyl-2,5-bis (2 3 g of ethylhexanoylperoxy) hexane was dissolved and mixed with methyl ethyl ketone as a solvent, and 3 vol% of the surface treated particles A were blended and dispersed. One side of 50 micrometers in thickness was apply | coated to the polyethylene terephthalate film which surface-treated using the simple coating machine, and it dried at 70 degreeC for 10 minutes, and obtained the adhesive for anisotropic conductive circuit connection of 30 micrometers in thickness.

Example 6

50 g of phenoxy resins (PKHC, Union Carbide Co., Ltd., average molecular weight 45,000), 46 g of isocyanuric acid ethylene oxide modified diacrylate, 4 g of phosphate ester acrylate, 2,5-dimethyl-2,5-bis (2-ethylhexa 3 g of noyl peroxy) hexane was dissolved and mixed with methyl ethyl ketone as a solvent, and 3 vol% of the surface treated particles B were dispersed. One side of 50 micrometers in thickness was apply | coated to the polyethylene terephthalate film which surface-treated using the simple coating machine, and it dried at 70 degreeC for 10 minutes, and obtained the adhesive for anisotropic conductive circuit connection of 30 micrometers in thickness.

Example 7

25 g of phenoxy resin (PKHC, trade name of Union Carbide, average molecular weight 45,000), 25 g of polyurethane resin, 48 g of dicyclohexyl methacrylate, 2 g of phosphate ester acrylate, 2,5-dimethyl-2,5-bis (2- 3 g of ethylhexanoylperoxy) hexane was dissolved and mixed with methyl ethyl ketone as a solvent, and 3 vol% of the surface treated particles B were dispersed and blended. One side of 50 micrometers in thickness was apply | coated to the polyethylene terephthalate film which surface-treated using the simple coating machine, and it dried at 70 degreeC for 10 minutes, and obtained the adhesive for anisotropic conductive circuit connection of 30 micrometers in thickness.

Example 8

50 g of phenoxy resin (PKHC, trade name of Union Carbide Co., Ltd., average molecular weight 45,000), 48 g of dicyclohexyl methacrylate as a radical polymerizable compound, 2 g of phosphate ester acrylate as a phosphate ester compound, 2,5-dimethyl-2,5- 3 g of bis (2-ethylhexanoylperoxy) hexane was dissolved and mixed with methyl ethyl ketone as a solvent, and 3 vol% of the surface treated particles C were blended and dispersed. One side of 50 micrometers in thickness was apply | coated to the polyethylene terephthalate film which surface-treated using the simple coating machine, and it dried at 70 degreeC for 10 minutes, and obtained the adhesive for anisotropic conductive circuit connection of 30 micrometers in thickness.

Example 9

50 g of phenoxy resins (PKHC, Union Carbide Co., Ltd., average molecular weight 45,000), 46 g of isocyanuric acid ethylene oxide modified diacrylate, 4 g of phosphate ester acrylate, 2,5-dimethyl-2,5-bis (2-ethylhexa 3 g of noyl peroxy) hexane was dissolved and mixed with methyl ethyl ketone as a solvent, and 3 vol% of the surface treated particles D were blended and dispersed. One side of 50 micrometers in thickness was apply | coated to the polyethylene terephthalate film which surface-treated using the simple coating machine, and it dried at 70 degreeC for 10 minutes, and obtained the adhesive for anisotropic conductive circuit connection of 30 micrometers in thickness.

Example 10

25 g of phenoxy resin (PKHC, trade name of Union Carbide Co., Ltd., average molecular weight 45,000), 25 g of polyurethane resin, 48 g of dicyclohexyl methacrylate, 2 g of phosphate ester acrylate, 2,5-dimethyl-2,5-bis (2 -3 g of ethylhexanoylperoxy) hexane was dissolved and mixed with methyl ethyl ketone as a solvent, and 3 vol% of the surface treated particles D were blended and dispersed. One side of 50 micrometers in thickness was apply | coated to the polyethylene terephthalate film which surface-treated using the simple coating machine, and it dried at 70 degreeC for 10 minutes, and obtained the adhesive for anisotropic conductive circuit connection of 30 micrometers in thickness.

Comparative Example 3

The adhesive for anisotropic conductive circuit connections was produced like Example 5 except having changed the surface-treated particle | grains A of Example 5 into the unprocessed particle | grains.

(Manufacture of circuit connection structure)

The anisotropic conductive circuit connection adhesive was slit in a width of 1.5 mm and semi-connected on a glass substrate on which ITO was formed as an electrode at 80 ° C., 5 seconds, and 1 MPa. The PET support base material was peeled off, and the electrode of TCP of 50 micrometers in width and space of 50 micrometers was bonded to this position, and this connection was made under conditions of 150 degreeC, 20 second, and 4 Mpa, and the circuit connection structure was produced.

(Characteristic evaluation method)

Connection resistance: The resistance between adjacent circuits was measured by the constant current of 1 mA using the multimeter TR6848 made from Adoban Test. The connection resistance measured the initial stage after connection, and the value after 30 degreeC, 60% RH, and 100 hours standing. The results are shown in Table 2.

TABLE 2

Item Connection resistance (Ω) Early After 30 ℃, 60% RH, 100 hours Example 5 2.1 2.4 Example 6 2.8 2.5 Example 7 3.2 3.1 Example 8 2.2 2.5 Example 9 2.4 2.4 Example 10 2.8 3.1 Comparative Example 3 2.4 34.7

In Examples 5 to 10 of the present invention, the connection resistance was low and good even after standing, but in Comparative Example 3 in which surface treated particles were not used, the connection resistance after standing was greatly increased. In addition, after the adhesive for anisotropic conductive circuit connection was prepared and left at 25 ° C. for 30 days, a circuit connection structure was produced in the same manner as in Example, and anisotropic containing conductive particles surface-treated with a compound having a basic compound or an epoxy group. The adhesive agent for conductive circuit connection showed good storage stability with the connection resistance (initial stage) of 2.1-3.8 ohm in the mixing | blending of Examples 5-10. However, the connection resistance of the connection structure using the conductive particles which were not treated with the basic compound or the compound having an epoxy group of Comparative Example 3 is inferior in storage stability to 20 to 200?.

According to the present invention, an adhesive for anisotropic conductive circuit connection with good storage stability (pot life) can be obtained even after the adhesive for anisotropic conductive circuit connection is produced, and the connection temperature of the thermosetting anisotropic conductive circuit connection adhesive can be obtained. With respect to 170 degreeC, it can connect at 150 degreeC of lower temperature, there is little difference of the connection resistance after storage of an adhesive agent, and can obtain a favorable connection structure.

Claims (13)

An adhesive for anisotropic conductive circuit connection, comprising a resin film-form formed by uniformly dispersing conductive particles, and comprising at least the following components. (1) conductive particles having no transition metal other than Ag, Au, or Pt exposed on their surface; (2) radically polymerizable materials, (3) A curing agent that generates free radicals by heating or light. An adhesive for anisotropic conductive circuit connection, comprising a resin film-form formed by uniformly dispersing conductive particles, and comprising at least the following components. (1) conductive particles having no transition metal other than Ag, Au, or Pt exposed on their surface; (2) radically polymerizable materials, (3) a curing agent that generates free radicals by heating or light, and (4) Phosphate ester compound. A circuit board for electrically connecting the electrodes in the pressing direction by pressing an anisotropic conductive circuit connection adhesive according to claim 1 or 2 between substrates having circuit electrodes opposed to each other, and pressing the substrates having opposite circuit electrodes. How to connect A connection in which the anisotropic conductive circuit connection adhesive according to claim 1 or 2 is interposed between substrates having circuit electrodes facing each other, and the substrates having circuit electrodes facing each other are pressed to electrically connect the electrodes in the pressing direction. Structure. An adhesive for anisotropic conductive circuit connection, which is interposed between substrates having opposite circuit electrodes and pressurizes substrates having opposite circuit electrodes to electrically connect the electrodes in the pressing direction, wherein the adhesive includes (1) radically polymerizable An adhesive for circuit connection comprising a conductive particle surface-treated with at least one compound selected from the group consisting of a compound and (2) a basic compound and a compound having at least one epoxy group. The adhesive for anisotropic conductive circuit connection according to claim 5, comprising a compound which generates radicals by light or heating. The adhesive for anisotropic conductive circuit connection according to claim 5 or 6, further comprising a phosphate ester compound. The adhesive for anisotropic conductive circuit connections according to claim 5 or 6, wherein the basic compound is an amino compound. delete 8. The adhesive for anisotropic conductive circuit connection according to claim 7, wherein the basic compound is an amino compound. An anisotropic conductive circuit connection, wherein the anisotropic conductive circuit connection adhesive is interposed between substrates having circuit electrodes facing each other, and the substrates having circuit electrodes facing each other are pressed to electrically connect the electrodes in the pressing direction. The adhesive agent for a circuit is the adhesive agent for anisotropic conductive circuit connections as described in any one of Claims 5-6 and 10. The circuit connection structure characterized by the above-mentioned. An anisotropic conductive circuit connection, wherein the anisotropic conductive circuit connection adhesive is interposed between substrates having circuit electrodes facing each other, and the substrates having circuit electrodes facing each other are pressed to electrically connect the electrodes in the pressing direction. The adhesive agent for an anisotropic conductive circuit connection adhesive agent of Claim 7, The circuit connection structure characterized by the above-mentioned. An anisotropic conductive circuit connection, wherein the anisotropic conductive circuit connection adhesive is interposed between substrates having circuit electrodes facing each other, and the substrates having circuit electrodes facing each other are pressed to electrically connect the electrodes in the pressing direction. The adhesive agent for an anisotropic conductive circuit connection adhesive agent of Claim 8 is a circuit connection structure characterized by the above-mentioned.