JP2011187489A - Method for manufacturing electronic component, electronic component, method for manufacturing electronic apparatus and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an electronic component enabling stable electric connection between substrates and between terminals equipped on each of the substrates, and obtaining a substrate-substrate bonded product which is excellent in productivity and in which the substrates are bonded, and to provide the electronic component. <P>SOLUTION: The manufacturing method includes melting a metal foil by heating the laminate of first and second substrates, forming a bonding portion by aggregating a metal foil between a first terminal of the first substrate and a second terminal of the second substrate and then solidifying it, and forming a reinforcing portion made of a resin composition in the periphery of the first and second terminals and the bonding portion. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electronic component manufacturing method, an electronic component, an electronic device manufacturing method, and an electronic device.

  In recent years, with the demand for higher functionality of electronic components, development of high-density mounting technology for electrically connecting substrates to each other has been advanced. As one of such mounting techniques, an electronic component that electrically connects a rigid substrate and a flexible substrate has been proposed. In this electronic component, it is necessary to connect a rigid substrate having a fine connection portion and a flexible substrate. Therefore, when the connection is performed by soldering, the solder bridges between adjacent connection portions, which causes a short circuit defect. There was a case.

  In order to improve the problems in manufacturing such electronic components, a rigid substrate and a flexible substrate, with an anisotropic conductive film (ACF) interposed therebetween, a rigid substrate, It has been proposed to perform electrical connection and adhesion by thermocompression bonding with a flexible substrate (Patent Document 1).

In the connection between such a rigid substrate using ACF and a flexible substrate, the metal particles contained in the ACF and the connection portion come into contact with each other, that is, electrical connection between the connection portions is caused by point contact between the metal particles. Connection is secured.

When the electronic component is driven in such a state, the resin component contained in the ACF expands / contracts due to heat generated from the rigid substrate / flexible substrate assembly and fluctuations in the outside air temperature. As a result, the distance between the connecting portions varies, and in some cases, the metal particles and the connecting portions are not in contact with each other, and the resistance value between the connecting portions does not fluctuate or become conductive. For this reason, there is a case in which stable conduction cannot be obtained between the connection portions in the connection between the rigid substrate using the ACF and the flexible substrate.
On the other hand, when the terminals of the rigid board / flexible board are electrically connected by printing solder paste, the terminals are connected by solder, but the gap between the rigid board / flexible board is not filled with an underfill material or the like. Due to the difference in coefficient of linear expansion between the rigid board and the flexible board, due to the heat generated from the rigid board / flexible board assembly and fluctuations in the outside air temperature, stress is applied to the soldered part, the solder cracks, In some cases, peeling occurs at the interface between the terminal and the solder, and conduction between the rigid substrate / flexible substrate is lost, resulting in a decrease in reliability. Further, when the gap between the rigid substrate / flexible substrate is not filled with an underfill material or the like, the reliability may be lowered due to an impact caused by dropping or the like.

JP 2005-268378 A

  An object of the present invention is to provide a substrate / substrate assembly in which a substrate and a substrate are bonded to each other, which can stably perform electrical connection between the substrates and the bonding portions included in the substrate and is excellent in productivity. An object is to provide an electronic component manufacturing method and an electronic component that can be obtained.

Such an object is achieved by the present invention described in the following (1) to (7).
(1) A method for manufacturing an electronic component in which a first substrate and a second substrate are stacked and electrically connected, and a first step of preparing each of the first substrate and the second substrate; Between the first substrate and the second substrate is interposed a conductive connection material having a laminated structure composed of a resin composition and a metal foil selected from solder foil or tin foil, The first substrate / the first substrate on which the first substrate and the second substrate are stacked by positioning so that the first terminal of the first substrate and the second terminal of the second substrate correspond to each other. A second step of obtaining a second substrate laminate, and heating the first substrate / second substrate laminate to melt the metal foil, and a first terminal of the first substrate; A metal foil is aggregated between the second terminals of the second substrate and then solidified to form a joint portion. Both the first terminal, the second terminal, and a third step of forming a reinforcing part made of the resin composition on the periphery of the joint part, and agglomeration in which the reinforcing part is cured or solidified and the metal foil is melted A first substrate / second substrate assembly is obtained in which the first terminal of the first substrate and the second terminal of the second substrate are electrically connected with a solidified product. And a method of manufacturing an electronic component, comprising:
(2) When the cross-sectional area of the gap between the first substrate and the second substrate assembly is S1, and the cross-sectional area of the reinforcing portion is S2, the relationship of S2 / S1 = 0.1 to 0.9 is satisfied. (1) the manufacturing method of the electronic component according to
(3) The method for producing an electronic component according to (1) or (2), wherein the resin composition contains a thermosetting resin,
(4) The method for producing an electronic component according to any one of (1) to (3), wherein the resin composition includes a compound having a flux function,
(5) The method for manufacturing an electronic component according to any one of (1) to (4), wherein the conductive connection material includes a laminated structure including a resin composition layer / metal foil layer / resin composition layer,
(6) The method for manufacturing an electronic component according to any one of (1) to (5), wherein the conductive connection material includes a laminated structure including a resin composition layer / metal foil layer,
(7) An electronic component manufactured by the method for manufacturing an electronic component according to any one of (1) to (6).

  According to the present invention, there can be provided a substrate / substrate assembly in which a substrate and a substrate are bonded to each other. An electronic component manufacturing method and an electronic component that can be obtained can be provided.

It is a longitudinal cross-sectional view which shows an example of the electronic component manufactured by the manufacturing method of the electronic component of this invention. It is a longitudinal cross-sectional view for demonstrating 1st Embodiment and 2nd Embodiment which join a rigid board | substrate and a flexible substrate. It is a longitudinal cross-sectional view for demonstrating the evaluation method of the reinforcement part of a rigid board | substrate / flexible board assembly.

  Hereinafter, a method for manufacturing an electronic component and an electronic component according to the present invention will be described in detail based on an embodiment shown in the accompanying drawings.

  First, prior to describing the method for manufacturing an electronic component of the present invention, an electronic component manufactured by the method for manufacturing an electronic component of the present invention will be described.

<Electronic parts>
FIG. 1 is a longitudinal sectional view showing an example of an electronic component manufactured by the electronic component manufacturing method of the present invention. In the following description, the upper side in FIG. 1 is referred to as “upper” and the lower side is referred to as “lower”.

  An electronic component 10 shown in FIG. 1 is an electronic component in which a rigid substrate 20 and a flexible substrate 30 are electrically connected and bonded, and includes a rigid substrate 20, a flexible substrate 30, and a semiconductor component 40. The semiconductor component 40 and the rigid substrate 20 are electrically connected via bumps 50. Further, the periphery of the bump 50 is sealed with a sealing material 60 for the purpose of protecting the bump 50. Further, the rigid substrate 20 and the flexible substrate 30 are configured such that the terminals 21 included in the rigid substrate and the terminals 31 included in the flexible substrate 30 are electrically connected by the joint portion 225, and the terminals and the joint portion are further connected by the reinforcing portion 226. 225 can be protected from external stress and insulation between adjacent terminals can be maintained.

  The rigid substrate 20 is an insulating substrate, and examples thereof include organic substrates, ceramic substrates, and the like whose main components are materials obtained by impregnating fiber base materials with various resin materials such as epoxy, cyanate, and bismaleimide triazine (BT resin). It is done. The shape of the rigid substrate 20 in plan view is usually a quadrangle such as a square or a rectangle.

  On the upper surface (one surface) of the rigid substrate 20, for example, a wiring pattern (not shown) made of a conductive metal material such as copper is provided in a predetermined shape.

  The flexible substrate 30 is an insulating substrate, is composed mainly of various resin materials such as polyimide and polyester, and is a flexible substrate.

On the lower surface (one surface) of the flexible substrate 30, for example, a wiring pattern (not shown) made of a conductive metal material such as copper is provided in a predetermined shape.
Here, a flexible substrate is illustrated as the substrate, but a rigid substrate, an organic substrate, a ceramic substrate, a semiconductor wafer, a semiconductor chip, a capacitor, a resistor chip, or the like may be used as the substrate.

  Although not particularly limited, the semiconductor component 40 is mounted on the rigid substrate 20, and the rigid substrate 20 and the semiconductor component 40 are electrically connected via the bumps 50. Further, the gap between the rigid substrate 20 and the semiconductor component 40 is sealed with a sealing material 60 as necessary. Thereby, the surface of the circuit surface of the semiconductor component 40 can be protected and the crack of the bump 50 can be prevented.

  The bumps 50 are mainly composed of a brazing material such as solder, silver brazing, copper brazing, and phosphor copper brazing.

Hereinafter, the conductive connection material according to the present invention will be described.
<Conductive connection material>
The conductive connecting material according to the present invention includes a resin composition containing a resin component and a compound having a flux function, and a metal foil selected from solder foil or tin foil. The form is a laminate having a multilayer structure composed of a resin composition layer and a metal foil layer, and each of the resin composition layer and the metal foil layer may be a single layer or a plurality of layers. The laminated structure of the conductive connecting material is not particularly limited, and may be a two-layer structure (resin composition layer / metal foil layer) of a resin composition layer and a metal foil layer, either a resin composition layer or a metal foil layer, or It may be a three-layer structure including a plurality of both or a multi-layer structure having more. In addition, when using two or more resin composition layers or metal foil layers, the composition of each layer may be the same or different.

  In one embodiment of the conductive connection material according to the present invention, from the viewpoint of reducing the surface oxide film of the metal foil with a compound having a flux function, the upper and lower layers of the metal foil layer are preferably resin composition layers. For example, a three-layer structure (resin composition layer / metal foil layer / resin composition layer) is preferable. In this case, the thickness of the resin composition layer on both sides of the metal foil layer may be the same or different. The thickness of the resin composition layer may be appropriately adjusted according to the conductor thickness of the electrode to be connected.

  Hereinafter, the resin composition and the metal foil layer constituting the conductive connection material according to the present invention will be described more specifically.

(1) Resin composition layer The resin composition according to the present invention is composed of a resin composition containing a resin component and a compound having a flux function. The resin composition can be used in a liquid or solid form at room temperature. In the present invention, “liquid at normal temperature” means a state that does not have a certain form at normal temperature (25 ° C.), and includes a paste form.

The resin composition according to the present invention is not particularly limited as long as it contains a resin component and a compound having a flux function, and a curable resin composition or a thermoplastic resin composition can be used. Examples of the curable resin composition include a curable resin composition that is cured by heating and a curable resin composition that is cured by irradiation with actinic radiation. Especially, the curable resin composition hardened | cured by heating is preferable at the point which is excellent in mechanical characteristics, such as a linear expansion coefficient and an elasticity modulus after hardening.
The thermoplastic resin composition is not particularly limited as long as it is flexible enough to be molded by heating to a predetermined temperature.

(A) Curable resin composition The curable resin composition preferably used as the resin composition according to the present invention contains a curable resin component and a compound having a flux function, and is melted and cured by heating. If there is no particular limitation.

In one embodiment of the present invention, the conductive connecting material of the present invention is disposed between the rigid substrate 20 and the flexible substrate 30 facing the rigid substrate 20, and the conductive connecting material is heated, whereby the metal foil is obtained by the action of the compound having a flux function. The surface oxide film is removed to improve the wettability of the metal. As a result, the melted solder or tin moves in the curable resin component, and agglomerates between the terminal 21 (first terminal) of the rigid substrate 20 and the terminal 31 (second terminal) of the flexible substrate 30 to join. 225 can be formed. On the other hand, the curable resin component can form the reinforcing portion 226 on the periphery of the terminal 21, the terminal 31, and the joint portion 225.
After the first terminal 21 and the second terminal 31 are electrically connected via solder or tin, conduction can be ensured by curing the curable resin component as necessary. In addition, the terminal 21, the terminal 31, and the joint 225 can be protected from external stress, and insulation between adjacent terminals can be ensured.

(I) Curable resin component The curable resin component which concerns on this invention will not be specifically limited if normally used as an adhesive agent component for semiconductor device manufacture. Such a curable resin component is not particularly limited, but is preferably one that cures at a temperature equal to or higher than the melting point of the metal foil. For example, an epoxy resin, a phenoxy resin, a silicone resin, an oxetane resin, a phenol resin, (Meth) acrylate resin, polyester resin (unsaturated polyester resin), diallyl phthalate resin, maleimide resin, polyimide resin (polyimide precursor resin), bismaleimide-triazine resin and the like. In particular, the use of a thermosetting resin containing at least one selected from the group consisting of epoxy resins, (meth) acrylate resins, phenoxy resins, polyester resins, polyimide resins, silicone resins, maleimide resins, and bismaleimide-triazine resins. preferable. Among these, an epoxy resin is preferable from the viewpoint of excellent curability and storage stability, heat resistance of the cured product, moisture resistance, and chemical resistance. Moreover, these curable resin components may be used individually by 1 type, or may use 2 or more types together.

The form of the curable resin component according to the present invention can be appropriately selected according to the form of the curable resin composition. When using a liquid curable resin composition, it is preferable to use a liquid curable resin component, and if necessary, a film-forming resin component described later may be used in combination. Moreover, when using a solid curable resin composition, both a liquid and solid curable resin component can be used, and it is preferable to use a film-forming resin component together.

  In the present invention, any epoxy resin that is liquid at room temperature and solid at room temperature can be used as the epoxy resin. It is also possible to use an epoxy resin that is liquid at room temperature and an epoxy resin that is solid at room temperature. When the curable resin composition is liquid, it is preferable to use an epoxy resin that is liquid at room temperature. When the curable resin composition is solid, both liquid and solid epoxy resins should be used. Is possible, film shape

The epoxy resin that is liquid at room temperature (25 ° C.) according to the present invention is not particularly limited, and examples thereof include bisphenol A type epoxy resins and bisphenol F type epoxy resins. Moreover, you may use together a bisphenol A type epoxy resin and a bisphenol F type epoxy resin.

  The epoxy equivalent of the epoxy resin that is liquid at room temperature is preferably 150 to 300 g / eq, more preferably 160 to 250 g / eq, and particularly preferably 170 to 220 g / eq. If the epoxy equivalent is less than the above lower limit, the shrinkage of the cured product tends to increase, and warping may occur. On the other hand, when the above upper limit is exceeded, when a film-forming resin component is used in combination, the reactivity with the film-forming resin component, particularly the polyimide resin, tends to decrease.

  The epoxy resin solid at room temperature (25 ° C.) according to the present invention is not particularly limited, but is bisphenol A type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, glycidylamine. Type epoxy resin, glycidyl ester type epoxy resin, trifunctional epoxy resin, tetrafunctional epoxy resin and the like. Among these, solid trifunctional epoxy resin, cresol novolac type epoxy resin and the like are preferable. Moreover, these epoxy resins may be used individually by 1 type, or may use 2 or more types together. The softening point of the epoxy resin that is solid at room temperature is preferably 40 to 120 ° C, more preferably 50 to 110 ° C, and particularly preferably 60 to 100 ° C. When the softening point is within the above range, tackiness can be suppressed and handling can be easily performed.

  In the present invention, commercially available products as such curable resin components can be used, and further, plasticizers, stabilizers, antioxidants, inorganic fillers, antistatic agents, as long as the effects of the present invention are not impaired. What mixed various additives, such as an agent and a pigment, can also be used.

In the conductive connection material according to the present invention, the content of the curable resin component can be appropriately set according to the form of the curable resin composition.
For example, when the curable resin composition is liquid, the content of the curable resin component is preferably 10% by weight or more, more preferably 15% by weight or more, based on the total weight of the curable resin composition, 20
% By weight or more is more preferable, 25% by weight or more is further more preferable, 30% by weight or more is still more preferable, and 35% by weight or more is particularly preferable. Further, it is preferably less than 100% by weight, more preferably 95% by weight or less, still more preferably 90% by weight or less, still more preferably 75% by weight or less, still more preferably 65% by weight or less, and particularly preferably 55% by weight or less.
When the curable resin composition is solid, the content of the curable resin component is preferably 5% by weight or more, more preferably 10% by weight or more, and more preferably 15% by weight with respect to the total weight of the curable resin composition. % Or more is more preferable, and 20% by weight or more is particularly preferable. Moreover, 90 weight% or less is preferable, 85 weight% or less is more preferable, 80 weight% or less is further more preferable, 75 weight% or less is still more preferable, 65 weight% or less is still more preferable, 55 weight% or less is especially preferable.
When the content of the curable resin component is within the above range, the electrical connection strength between the terminals and the mechanical adhesive strength can be sufficiently secured.

(Ii) Film-forming resin component In the present invention, when a solid curable resin composition is used, the curable resin component and the film-forming resin component are preferably used in combination. Such a film-forming resin component is not particularly limited as long as it is soluble in an organic solvent and has film-forming properties alone. Either a thermoplastic resin or a thermosetting resin can be used, and these can be used in combination. Specific film-forming resin components include, for example, (meth) acrylic resins, phenoxy resins, polyester resins, polyurethane resins, polyimide resins, polyamideimide resins, siloxane-modified polyimide resins, polybutadiene resins, polypropylene resins, styrene-butadienes -Styrene copolymer, styrene-ethylene-butylene-styrene copolymer, polyacetal resin, polyvinyl butyral resin, polyvinyl acetal resin, butyl rubber, chloroprene rubber, polyamide resin, acrylonitrile-butadiene copolymer, acrylonitrile-butadiene-acrylic acid copolymer Examples thereof include polymers, acrylonitrile-butadiene-styrene copolymers, polyvinyl acetate, and nylon. Among these, (meth) acrylic resins, phenoxy resins, polyester resins, polyamide resins and polyimide resins are preferable. Moreover, these film-forming resin components may be used individually by 1 type, or may use 2 or more types together.

  In the present invention, “(meth) acrylic resin” refers to a polymer of (meth) acrylic acid and its derivatives, or a copolymer of (meth) acrylic acid and its derivatives and other monomers. means. Here, “(meth) acrylic acid” or the like means “acrylic acid or methacrylic acid” or the like.

Examples of the (meth) acrylic resin include polyacrylic acid, polymethacrylic acid, polymethyl acrylate, polyethyl acrylate, polybutyl acrylate, polyacrylic acid-2-ethylhexyl and other polyacrylic acid esters, poly Polymethacrylic acid esters such as methyl methacrylate, polyethyl methacrylate, polybutyl methacrylate, polyacrylonitrile, polymethacrylonitrile, polyacrylamide, butyl acrylate-ethyl acrylate-acrylonitrile copolymer, acrylonitrile-butadiene copolymer , Acrylonitrile-butadiene-acrylic acid copolymer, acrylonitrile-butadiene-styrene copolymer, acrylonitrile-styrene copolymer, methyl methacrylate-styrene copolymer, methyl methacrylate Acrylonitrile copolymer, methyl methacrylate-α-methylstyrene copolymer, butyl acrylate-ethyl acrylate-acrylonitrile-2-hydroxyethyl methacrylate-methacrylic acid copolymer, butyl acrylate-ethyl acrylate-acrylonitrile-2 -Hydroxyethyl methacrylate-acrylic acid copolymer, butyl acrylate-acrylonitrile-2-hydroxyethyl methacrylate copolymer, butyl acrylate-acrylonitrile-acrylic acid copolymer, butyl acrylate-ethyl acrylate-acrylonitrile copolymer , Ethyl acrylate-acrylonitrile-
Examples thereof include N, N-dimethylacrylamide copolymer. Of these, butyl acrylate-ethyl acrylate-acrylonitrile copolymer and ethyl acrylate-acrylonitrile-N, N-dimethylacrylamide are preferable. Moreover, these (meth) acrylic resins may be used alone or in combination of two or more.

  Among such (meth) acrylic resins, from the viewpoint that adhesion to the rigid substrate 20 or the flexible substrate 30 and compatibility with other resin components can be improved, a nitrile group, an epoxy group, a hydroxyl group, A (meth) acrylic resin obtained by copolymerizing a monomer having a functional group such as a carboxyl group is preferred. In such a (meth) acrylic resin, the compounding amount of the monomer having the functional group is not particularly limited, but is 0.1 to 0.1 mol based on 100 mol% of all monomers during the synthesis of the (meth) acrylic resin. It is preferably 50 mol%, more preferably 0.5 to 45 mol%, and particularly preferably 1 to 40 mol%. When the blending amount of the monomer having the functional group is less than the lower limit value, the adhesion tends not to be sufficiently improved. On the other hand, when the upper limit is exceeded, the adhesive force is too strong and the workability is not sufficiently improved. It is in.

  The weight average molecular weight of the (meth) acrylic resin is not particularly limited, but is preferably 100,000 or more, more preferably 150,000 to 1,000,000, and particularly preferably 250,000 to 900,000. When the weight average molecular weight is within the above range, the film forming property can be improved.

  In the present invention, when a phenoxy resin is used as the film-forming resin component, the number average molecular weight is preferably 5000 to 15000, more preferably 6000 to 14000, and particularly preferably 8000 to 12000. By using such a phenoxy resin, the fluidity of the conductive connecting material before curing can be suppressed.

  Examples of the skeleton of the phenoxy resin include a bisphenol A type, a bisphenol F type, and a biphenyl type, but are not limited to these in the present invention.

  The polyimide resin used in the present invention is not particularly limited as long as the resin has an imide bond in the repeating unit. For example, diamine and acid dianhydride are reacted, and the obtained polyamic acid is heated and dehydrated and cyclized. Can be obtained.

  Examples of the diamine include aromatic diamines such as 3,3′-dimethyl-4,4′diaminodiphenyl, 4,6-dimethyl-m-phenylenediamine, and 2,5-dimethyl-p-phenylenediamine, Examples thereof include siloxane diamines such as 3-bis (3-aminopropyl) -1,1,3,3-tetramethyldisiloxane. These diamines may be used alone or in combination of two or more.

  Examples of the acid dianhydride include 3,3,4,4'-biphenyltetracarboxylic acid, pyromellitic dianhydride, 4,4'-oxydiphthalic dianhydride, and the like. These acid dianhydrides may be used alone or in combination of two or more.

  The polyimide resin used in the present invention may be either soluble or insoluble in a solvent, but is easy to varnish when mixed with other components, and is solvent-soluble in terms of excellent handling properties. Those are preferred. In particular, a siloxane-modified polyimide resin is preferably used because it can be dissolved in various organic solvents.

The polyamide resin used in the present invention is not particularly limited. For example, 6-nylon,
Ring-opening polymerization of cycloaliphatic lactams such as 12-nylon, condensed 6,6-nylon, 4,6-nylon, 6,10-nylon, 6,12-nylon and other aliphatic diamines and aliphatic dicarboxylic acids. Examples thereof include a polymerized product, a product obtained by condensation polymerization of an aromatic diamine and an aliphatic dicarboxylic acid, a product obtained by condensation polymerization of an aromatic diamine and an aromatic dicarboxylic acid, and a product obtained by condensation polymerization of an amino acid.

Although the molecular weight of the polyamide resin used by this invention is not restrict | limited in particular, For example, 5000-100000 are preferable and 8000-50000 are especially preferable. If the molecular weight is not more than the above range, the moldability is good, but the mechanical strength of the film is weak, and if it is not less than the above range, the viscosity becomes high, thereby inhibiting the movement of solder or tin, resulting in poor conduction.
The polyamide resin used in the present invention may be either soluble or insoluble in a solvent, but it is easy to varnish when mixed with other components, and is solvent-soluble in that it is easy to handle. Those are more preferred.

  The polyester resin used in the present invention is not particularly limited, but a divalent acid such as terephthalic acid or a derivative thereof having an ester forming ability is used as an acid component, a glycol having 2 to 10 carbon atoms as a glycol component, other A saturated polyester resin obtained using a divalent alcohol or a derivative thereof having an ester-forming ability.

  Examples of the polyester resin include polyalkylene terephthalate resins such as polyethylene terephthalate resin, polybutylene terephthalate resin, polytrimethylene terephthalate resin, and polyhexamethylene terephthalate resin.

  The polyester resin may be a polyester resin copolymerized with other components as necessary. The component to be copolymerized is not particularly limited, and examples thereof include known acid components, alcohol components, phenol components, derivatives thereof having ester forming ability, polyalkylene glycol components, and the like.

  Examples of the copolymerizable acid component include a divalent or higher aromatic carboxylic acid having 8 to 22 carbon atoms, a divalent or higher aliphatic carbon carboxylic acid having 4 to 12 carbons, and a divalent or higher carbon. The alicyclic carboxylic acid of several 8-15, and these derivatives which have ester formation ability are mentioned. Specific examples of the copolymerizable acid component include terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, bis (p-carbodiphenyl) methaneanthracene dicarboxylic acid, 4-4′-diphenylcarboxylic acid, and 1,2-bis. (Phenoxy) ethane-4,4′-dicarboxylic acid, 5-sodium sulfoisophthalic acid, adipic acid, sebacic acid, azelaic acid, dodecanedioic acid, maleic acid, trimesic acid, trimellitic acid, pyromellitic acid, 1,3 -Cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid and derivatives thereof having the ability to form esters. These can be used alone or in combination of two or more.

  Examples of the copolymerizable alcohol and / or phenol component include dihydric or higher aliphatic alcohols having 2 to 15 carbon atoms, divalent or higher alicyclic alcohols having 6 to 20 carbon atoms, and 6 to 40 carbon atoms. These divalent or higher valent aromatic alcohols or phenols and derivatives thereof having the ability to form esters. Specific examples of the copolymerizable alcohol and / or phenol component include ethylene glycol, propanediol, butanediol, hexanediol, decanediol, neopentylglycol, cyclohexanedimethanol, cyclohexanediol, 2,2′-bis ( 4-hydroxyphenyl) propane, 2,2′-bis (4-hydroxycyclohexyl) propane, hydroquinone, glycerin, pentaerythritol, and the like, derivatives having ester forming ability, and cyclic esters such as ε-caprolactone Can be mentioned.

  Examples of the copolymerizable polyalkylene glycol component include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, random or block copolymers thereof, and alkylene glycols of bisphenol compounds (polyethylene glycol, polypropylene glycol, polytetramethylene). And modified polyoxyalkylene glycols such as adducts such as glycol and random or block copolymers thereof.

  In the present invention, commercially available products can be used as such film-forming resin components, and further, plasticizers, stabilizers, inorganic fillers, antioxidants, antistatic agents, as long as the effects of the present invention are not impaired. What mixed various additives, such as an agent and a pigment, can also be used.

In the conductive connection material according to the present invention, the content of the film-forming resin component can be appropriately set according to the form of the curable resin composition to be used.
For example, in the case of a solid curable resin composition, the content of the film-forming resin component is preferably 5% by weight or more with respect to the total weight of the curable resin composition, and is 10% by weight. More preferably, it is more preferably 15% by weight or more. Further, it is preferably 50% by weight or less, more preferably 45% by weight or less, and particularly preferably 40% by weight or less. When the content of the film-forming resin component is within the above range, the fluidity of the curable resin composition before melting can be suppressed, and the conductive connecting material can be easily handled.

(Iii) Compound having a flux function The compound having a flux function according to the present invention has an action of reducing the surface oxide film of the metal foil. As the compound having such a flux function, a compound having a phenolic hydroxyl group and / or a carboxyl group is preferable. Examples of the compound having a phenolic hydroxyl group include phenol, o-cresol, 2,6-xylenol, p-cresol, m-cresol, o-ethylphenol, 2,4-xylenol, 2,5-xylenol, m- Ethylphenol, 2,3-xylenol, meditol, 3,5-xylenol, p-tert-butylphenol, catechol, p-tert-amylphenol, resorcinol, p-octylphenol, p-phenylphenol, bisphenol F, bisphenol AF, biphenol Monomers containing phenolic hydroxyl groups such as diallyl bisphenol F, diallyl bisphenol A, trisphenol, tetrakisphenol, phenol novolac resins, o-cresol novolac resins, bisphenols Nord F novolak resins, resins containing phenolic manufactured hydroxyl and bisphenol A novolac resins.

  Examples of the compound having a carboxyl group include an aliphatic acid anhydride, an alicyclic acid anhydride, an aromatic acid anhydride, an aliphatic carboxylic acid, and an aromatic carboxylic acid. Examples of the aliphatic acid anhydride include succinic anhydride, polyadipic acid anhydride, polyazeline acid anhydride, and polysebacic acid anhydride. Examples of the alicyclic acid anhydride include methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylhymic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, trialkyltetrahydrophthalic anhydride, methylcyclohexene dicarboxylic acid. An anhydride etc. are mentioned. Examples of the aromatic acid anhydride include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bistrimellitate, and glycerol tris trimellitate.

Examples of the aliphatic carboxylic acid include formic acid, acetic acid, propionic acid, butyric acid, valeric acid, pivalic acid, caproic acid, caprylic acid, lauric acid, myristic acid, palmitic acid, stearic acid,
Examples include acrylic acid, methacrylic acid, crotonic acid, oleic acid, fumaric acid, maleic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, sebacic acid, dodecanedioic acid, and pimelic acid. Among them, the following formula (1):
_{HOOC- (CH 2) n -COOH (} 1)
(In Formula (1), n is an integer of 1-20.)
Are preferable, and adipic acid, sebacic acid, and dodecanedioic acid are more preferable.

［式中、Ｒ^１〜Ｒ^５は、それぞれ独立して、１価の有機基であり、Ｒ^１〜Ｒ^５の少なくとも一つは水酸基である。］

［式中、Ｒ^６〜Ｒ^２０は、それぞれ独立して、１価の有機基であり、Ｒ^６〜Ｒ^２０の少なくとも一つは水酸基又はカルボキシル基である。］ The structure of the aromatic carboxylic acid is not particularly limited, but a compound represented by the following formula (2) or (3) is preferable.

[Wherein, R ^{1 to} R ⁵ are each independently a monovalent organic group, and at least one of R ^{1 to} R ⁵ is a hydroxyl group. ]

[Wherein, R ^{6 to} R ²⁰ are each independently a monovalent organic group, and at least one of R ^{6 to} R ²⁰ is a hydroxyl group or a carboxyl group. ]

Examples of the aromatic carboxylic acid include benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, hemimellitic acid, trimellitic acid, trimesic acid, merophanic acid, platnic acid, pyromellitic acid, meritic acid, xylic acid, hemelic acid, Mesitylene acid, planicylic acid, toluic acid, cinnamic acid, salicylic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, gentisic acid (2,5-dihydroxybenzoic acid), 2,6-dihydroxybenzoic acid 3,5-dihydroxybenzoic acid, gallic acid (3,4,5-trihydroxybenzoic acid), 4-dihydroxy-2-naphthoic acid, 3,5-dihydroxy-2-naphthoic acid, 3,5-2 -Naphthoic acid derivatives such as dihydroxy-2-naphthoic acid; phenolphthaline; diphenolic acid, etc. .

  Among the compounds having such a flux function, the compound that acts as a curing agent for the curable resin component, that is, the surface oxide film of the metal foil and the terminal is reduced to such an extent that the metal foil and the terminal can be electrically connected. A compound having a functional group capable of reacting with the curable resin component is more preferable. The functional group can be appropriately selected according to the type of the curable resin component. For example, when the curable resin component is an epoxy resin, it can react with an epoxy group such as a carboxyl group, a hydroxyl group, and an amino group. A functional group is mentioned. Such a compound having a flux function reduces the surface oxide film of the metal foil when the conductive connection material is melted to increase the wettability of the surface of the metal foil, easily forms a joint, and electrically connects the terminals. It becomes possible to do. In addition, after the electrical connection between the terminals is completed, this compound acts as a curing agent and can be added to the curable resin component to increase the elastic modulus or Tg of the resin. Therefore, when a compound having such a flux function is used as the flux, flux cleaning is unnecessary and it is possible to suppress the occurrence of ion migration due to the remaining flux.

Examples of the compound having such a function and having a flux function include compounds having at least one carboxyl group. For example, when the curable resin component is an epoxy resin, examples thereof include aliphatic dicarboxylic acids and compounds having a carboxyl group and a phenolic hydroxyl group.
The aliphatic dicarboxylic acid is not particularly limited, and examples thereof include compounds in which two carboxyl groups are bonded to an aliphatic hydrocarbon group. The aliphatic hydrocarbon group may be saturated or unsaturated acyclic, or may be saturated or unsaturated cyclic. Further, when the aliphatic hydrocarbon group is acyclic, it may be linear or branched.

  Examples of such aliphatic dicarboxylic acids include compounds in which n is an integer of 1 to 20 in the formula (1). When n in the formula (1) is within the above range, the balance between the flux activity, the outgas at the time of bonding, the elastic modulus after curing of the conductive connecting material, and the glass transition temperature becomes good. In particular, n is preferably 3 or more from the viewpoint that the increase in the elastic modulus after curing of the conductive connecting material can be suppressed and the adhesion with the rigid substrate 20 and the flexible substrate 30 can be improved. N is preferably 10 or less from the viewpoint of suppressing the decrease in the resistance and further improving the connection reliability.

  Examples of the aliphatic dicarboxylic acid represented by the formula (1) include glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, and pentadecane. Examples include diacid, octadecanedioic acid, nonadecanedioic acid, and eicosanedioic acid. Among these, adipic acid, suberic acid, sebacic acid and dodencandioic acid are preferable, and sebacic acid is particularly preferable.

  Examples of the compound having a carboxyl group and a phenolic hydroxyl group include salicylic acid, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, gentisic acid (2,5-dihydroxybenzoic acid), and 2,6-dihydroxybenzoic acid. Benzoic acid derivatives such as acid, 3,4-dihydroxybenzoic acid, gallic acid (3,4,5-trihydroxybenzoic acid); 1,4-dihydroxy-2-naphthoic acid, 3,5-dihydroxy-2- Naphthoic acid derivatives such as naphthoic acid; phenolphthaline; diphenolic acid and the like. Of these, phenolphthaline, gentisic acid, 2,4-dihydroxybenzoic acid, and 2,6-dihydroxybenzoic acid are preferable, and phenolphthalin and gentisic acid are particularly preferable.

The compound having a flux function according to the present invention may be used alone or in combination of two or more. In addition, since any compound easily absorbs moisture and causes voids, in the present invention, it is preferable to dry it before use.

In the conductive connection material according to the present invention, the content of the compound having the flux function can be appropriately set according to the form of the curable resin composition to be used.
For example, when the curable resin composition is liquid, the content of the compound having a flux function is preferably 1% by weight or more, more preferably 2% by weight or more, based on the total weight of the curable resin composition, 3% by weight or more is particularly preferable. Moreover, 50 weight% or less is preferable, 40 weight% or less is more preferable, 30 weight% or less is further more preferable, and 25 weight% or less is especially preferable.
In the case of a solid resin composition, the content of the compound having a flux function is preferably 1% by weight or more, more preferably 2% by weight or more, more preferably 3% by weight with respect to the total weight of the curable resin composition. % Or more is particularly preferable. Moreover, 50 weight% or less is preferable, 40 weight% or less is more preferable, 30 weight% or less is further more preferable, and 25 weight% or less is especially preferable.
When the content of the compound having the flux function is within the above range, the metal foil and the surface oxide film of the terminal can be removed to such an extent that they can be electrically joined. Furthermore, the elastic modulus or Tg of the resin can be increased by efficiently adding to the resin at the time of curing. Moreover, generation | occurrence | production of the ion migration resulting from the compound which has an unreacted flux function can be suppressed.

  The curable resin composition according to the present invention preferably contains a curing accelerator. By adding a curing accelerator, a curable resin composition having the melt viscosity and the insulation resistance value can be easily obtained.

  Such curing accelerators include imidazole, 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2 -Phenyl-4-methylimidazole, 1-benzyl-2-phenylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1- Cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino- 6- [ '-Methylimidazolyl (1')]-ethyl-s-triazine, 2,4-diamino-6- [2'-undecylimidazolyl (1 ')]-ethyl-s-triazine, 2,4-diamino-6 -[2'-ethyl-4-methylimidazolyl (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-methylimidazolyl (1')]-ethyl-s-triazine isocyanuric Acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-methylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxydimethylimidazole, 2-phenyl-4-methyl-5-hy

Among these, from the viewpoint that the solder or tin can move to the surface of the terminals before the curing of the curable resin composition is completed and the terminals can be connected well, an imidazole compound having a melting point of 150 ° C. or higher is used. preferable. Examples of imidazole having a melting point of 150 ° C. or higher include 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 2,4-diamino-6- [2′-methylimidazolyl]. (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2′-undecylimidazolyl (1 ′)]-ethyl-s-triazine, 2,4-diamino-6- [2 ′ -Ethyl-4-methylimidazolyl (1 ')]-ethyl-s-triazine, 2,4-diamino-6- [2'-methylimidazolyl (1')]-ethyl-s-triazine isocyanuric acid adduct, Isocyanuric acid adduct of 2-phenylimidazole, 2-phenyl-4,5-dihydroxydimethylimidazole, 2-phenyl-4-methyl-5-hydroxy Such as methylimidazole. Moreover, in this invention, such a hardening accelerator may be used individually by 1 type, or may use 2 or more types together.

In the conductive connection material according to the present invention, the content of the curing accelerator can be appropriately set according to the type of the curing accelerator to be used.
For example, when an imidazole compound is used, the content of the imidazole compound is preferably 0.001% by weight or more, more preferably 0.003% by weight or more, based on the total weight of the curable resin composition. 0.005% by weight or more is particularly preferable. Moreover, 1.0 weight% or less is preferable, 0.7 weight% or less is more preferable, and 0.5 weight% or less is especially preferable. When the content of the imidazole compound is less than the lower limit, the effect as a curing accelerator is not sufficiently exhibited, and the curable resin composition may not be sufficiently cured. On the other hand, when the content of the imidazole compound exceeds the above upper limit, the solder or tin does not move sufficiently to the terminal surface before the curing of the curable resin composition is completed, and the solder or tin remains in the insulating region and is insulative. May not be sufficient. In addition, the storage stability of the conductive connection material may be reduced.

(Iv) Other additives The curable resin composition according to the present invention includes a curing agent (excluding those acting as a flux), a silane coupling agent, a plasticizer, a stabilizer, a tackifier, a lubricant, and an antioxidant. Additives such as agents, fillers, antistatic agents and pigments may further be included.

  Examples of the curing agent other than the compound having a flux function include phenols, amines, and thiols. Such a hardening | curing agent can be suitably selected according to the kind etc. of curable resin component. For example, when an epoxy resin is used as the curable resin component, good reactivity with the epoxy resin, low dimensional change during curing, and appropriate physical properties after curing (eg, heat resistance, moisture resistance, etc.) are obtained. In view of the above, it is preferable to use a phenol as a curing agent, and a bifunctional or higher functional phenol is more preferable in terms of excellent physical properties after curing of the curable resin component. Moreover, such a hardening | curing agent may be used individually by 1 type, and may use 2 or more types together.

  Examples of such phenols include bisphenol A, tetramethylbisphenol A, diallyl bisphenol A, biphenol, bisphenol F, diallyl bisphenol F, trisphenol, tetrakisphenol, phenol novolac resin, cresol novolac resin, and the like. Of these, phenol novolac resins and cresol novolac resins are preferred because they have good melt viscosity and reactivity with epoxy resins and are excellent in physical properties after curing.

  In the conductive connection material according to the present invention, the compounding amount of the curing agent is such that the type of the curable resin component and the curing agent to be used, and the compound having a flux function have a functional group that functions as a curing agent. Can be appropriately selected depending on the type and amount of use. For example, when a phenol novolac resin is used, its blending amount is preferably 1% by weight or more, more preferably 3% by weight or more, more preferably 5% by weight with respect to the total weight of the curable resin composition. % Or more, particularly preferably 50% by weight or less, more preferably 40% by weight or less, and particularly preferably 30% by weight or less. When the amount of the phenol novolac resin is less than the lower limit, the curable resin component tends not to be cured sufficiently, and when the amount exceeds the upper limit, the unreacted phenol novolac resin remains and the ion migration tends to occur. is there.

Further, when an epoxy resin is used as the curable resin component, the blending amount of the phenol novolac resin may be defined by an equivalent ratio with respect to the epoxy resin. For example, the equivalent ratio of phenol novolac resin to epoxy resin is preferably 0.5 to 1.2, more preferably 0.6 to 1.1, and 0.7 to 0.98. Particularly preferred. When the equivalent ratio is less than the lower limit, the heat resistance and moisture resistance after curing of the epoxy resin tend to decrease, and when the upper limit is exceeded, unreacted phenol novolac resin remains and ion migration occurs. It tends to be easy to do.

  Examples of the silane coupling agent include an epoxy silane coupling agent and an aromatic-containing aminosilane coupling agent. By adding such a silane coupling agent, the adhesion between the rigid substrate 20 or the flexible substrate 30 and the conductive connection material can be enhanced. Moreover, such a silane coupling agent may be used individually by 1 type, and may use 2 or more types together.

  In the conductive connection material according to the present invention, the blending amount of the silane coupling agent can be appropriately selected according to the type of the interface of the rigid substrate 20 or the flexible substrate 30, the curable resin component, etc. It is preferably 0.01% by weight or more, more preferably 0.05% by weight or more, particularly preferably 0.1% by weight or more, based on the total weight of the resin composition, It is preferably 2% by weight or less, more preferably 1.5% by weight or less, and particularly preferably 1% by weight or less.

  In the present invention, the curable resin composition can be prepared by mixing and dispersing the above components. The mixing method and dispersion method of each component are not specifically limited, It can mix and disperse | distribute by a conventionally well-known method.

  In the present invention, a liquid curable resin composition may be prepared by mixing the above components in a solvent or without a solvent. The solvent used at this time is not particularly limited as long as it is inert to each component. For example, acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), diisobutyl ketone (DIBK), cyclohexanone, Ketones such as diacetone alcohol (DAA); aromatic hydrocarbons such as benzene, xylene and toluene; alcohols such as methyl alcohol, ethyl alcohol, isopropyl alcohol and n-butyl alcohol; methyl cellosolve, ethyl cellosolve, butyl cellosolve; Cellosolves such as methyl cellosolve acetate and ethyl cellosolve acetate, N-methyl-2-pyrrolidone (NMP), tetrahydrofuran (THF), dimethylformamide (DMF), dibasic acid ester (DB ), Ethyl 3-ethoxypropionate (EEP), and dimethyl carbonate (DMC). Moreover, it is preferable that the usage-amount of a solvent is an quantity from which the solid content concentration of the component mixed with the solvent will be 10 to 80 weight%.

(B) Thermoplastic resin composition In this invention, a thermoplastic resin composition can also be used as a resin composition.
The thermoplastic resin composition used in the present invention is not particularly limited as long as it contains a thermoplastic resin component and a compound having a flux function and softens at a predetermined temperature.

(I) Thermoplastic resin component The thermoplastic resin component is not particularly limited. For example, vinyl acetate, polyvinyl alcohol resin, polyvinyl butyral resin, vinyl chloride resin, (meth) acrylic resin, phenoxy resin, polyester resin, Polyimide resin, polyamideimide resin, siloxane-modified polyimide resin, polybutadiene resin, acrylic resin, styrene resin, polyethylene resin, polypropylene resin, polyamide resin, cellulose resin, isobutylene resin, vinyl ether resin, liquid crystal polymer resin, polyphenylene sulfide resin, polyphenylene ether resin , Polyethersulfone resin, polyetherimide resin, polyetheretherketone resin, polyurethane resin, styrene-butadiene-styrene copolymer, styrene -Ethylene-butylene-styrene copolymer, polyacetal resin, polyvinyl butyral resin, polyvinyl acetal resin, butyl rubber, chloroprene rubber, acrylonitrile-butadiene copolymer, acrylonitrile-butadiene-acrylic acid copolymer, acrylonitrile-butadiene-styrene copolymer And coalesced and polyvinyl acetate. The thermoplastic resin component may be a single polymer or a copolymer of at least two of the thermoplastic resin components.

The softening point of the thermoplastic resin component is not particularly limited, but is preferably 10 ° C. or more lower than the melting point of the metal foil constituting the conductive connection material, particularly preferably 20 ° C. or more, and more preferably 30 ° C. or less. It is more preferable.
The decomposition temperature of the thermoplastic resin component is not particularly limited, but is preferably 10 ° C. or higher, particularly preferably 20 ° C. or higher, more preferably 30 ° C. higher than the melting point of the metal foil constituting the conductive connecting material. More preferably, it is higher.

Content of the said thermoplastic resin can be suitably set according to the form of the thermoplastic resin composition to be used.
For example, when the thermoplastic resin composition is liquid, the content of the thermoplastic resin component is preferably 10% by weight or more, more preferably 15% by weight or more, and more preferably 20% by weight with respect to the total weight of the thermoplastic resin composition. % Or more is more preferable, 25% by weight or more is further more preferable, 30% by weight or more is still more preferable, and 35% by weight or more is particularly preferable. Moreover, 100 weight% or less is preferable, 95 weight% or less is more preferable, 90 weight% or less is more preferable, 75 weight% or less is still more preferable, 65 weight% or less is still more preferable, 55 weight% or less is especially preferable.
When the thermoplastic resin composition is solid, the content of the thermoplastic resin component is preferably 5% by weight or more, more preferably 10% by weight or more, and more preferably 15% by weight with respect to the total weight of the thermoplastic resin composition. % Or more is more preferable, and 20% by weight or more is particularly preferable. Moreover, 90 weight% or less is preferable, 85 weight% or less is more preferable, 80 weight% or less is further more preferable, 75 weight% or less is still more preferable, 65 weight% or less is still more preferable, 55 weight% or less is especially preferable.
When the content of the thermoplastic resin component is within the above range, the electrical connection strength and the mechanical adhesive strength between the terminals can be sufficiently ensured.

(Ii) Compound having flux function The compound having the flux function may be the same as described in the above “(a) curable resin composition”. The same applies to preferred compounds and blending amounts.

(Iii) Other additives In addition to the above thermoplastic resin components, silane coupling agents, plasticizers, stabilizers, tackifiers, lubricants, antioxidants, and fillers as long as the effects of the present invention are not impaired. Further, an antistatic agent or a pigment may be blended.

  In the conductive connection material according to the present invention, the thickness of the resin composition layer is not particularly limited, but is preferably 1 μm or more, more preferably 3 μm or more, and particularly preferably 5 μm or more. The thickness of the resin composition layer is preferably 200 μm or less, more preferably 150 μm or less, and particularly preferably 100 μm or less. When the thickness of the resin composition layer is within the above range, the periphery of the joint can be sufficiently reinforced, the joint can be protected from external stress, and insulation between adjacent terminals can be ensured. Can do.

When the conductive connection material of the present invention includes a plurality of resin composition layers, the composition of each resin composition layer may be the same, or may differ depending on the type of resin component used, the difference in formulation, and the like. The physical properties such as melt viscosity and softening temperature of the resin composition layer may be the same or different. For example, a liquid resin composition layer and a solid resin composition layer may be used in combination.

(2) Metal foil layer In this invention, a metal foil layer is a layer comprised with the metal foil chosen from solder foil or tin foil. The metal foil layer should just be formed in at least one part of the resin composition layer by planar view, and may be formed in the whole surface of the resin composition layer.

  The shape of the metal foil layer is not particularly limited, and a certain shape may be repeatedly formed in a pattern shape, or the shape may be irregular. Regular shapes and irregular shapes may be mixed. As the shape of the metal foil layer, for example, a dotted pattern (a), a striped pattern (b), a polka dot pattern (c), a rectangular pattern (d), a checkered pattern (e), a frame shape ( f), lattice pattern (g), multiple frame shapes (h), and the like. These shapes are examples, and these shapes can be combined or deformed depending on the purpose and application.

  In one embodiment of the present invention, when connecting a full grid type adherend in which terminals to be connected are arranged on the entire connection surface of the rigid substrate 20 and the flexible substrate 30, the entire surface of the resin composition layer It is preferable to form a sheet-like metal foil.

In addition, when the terminals to be connected are different in the density of the terminal density or unevenly distributed in the connection surface of the rigid substrate 20 and the flexible substrate 30, a viewpoint of effectively using the metal foil, and between adjacent terminals From the viewpoint of preventing the metal foil from remaining on the resin composition layer, it is preferable to repeatedly form a patterned metal foil on at least a part of the resin composition layer. At this time, the shape of the metal foil can be appropriately selected depending on the pitch and form of the terminals.

  The metal foil used in the present invention is not particularly limited, and tin (Sn), lead (Pb), silver (Ag), bismuth (Bi), indium (In), zinc (Zn), nickel (Ni), antimony (Sb), iron (Fe), aluminum (Al), gold (Au), germanium (Ge), an alloy of at least two metals selected from the group consisting of copper (Cu), or a simple tin Is preferred.

  Among these alloys, in consideration of melting temperature and mechanical properties, Sn—Pb alloy, Sn—Bi alloy which is lead-free solder, Sn—Ag—Cu alloy, Sn—In alloy, Sn— More preferably, it is made of an alloy containing Sn, such as an alloy of Ag. In the case of an Sn-Pb alloy, the tin content is preferably 30% by weight or more and less than 100% by weight, more preferably 35% by weight or more and less than 100% by weight, and particularly preferably 40% by weight or more. . Moreover, it is preferable that it is less than 100 weight%. In the case of lead-free solder, the tin content is preferably 15% by weight or more and less than 100% by weight, more preferably 20% by weight or more and less than 100% by weight, and more preferably 25% by weight or more and less than 100% by weight. It is particularly preferred that it is less than. For example, Sn-Pb alloy is Sn63-Pb (melting point 183 ° C), and lead-free solder is Sn-3.0Ag-0.5Cu (melting point 217 ° C), Sn-3.5Ag (melting point 221 ° C) Sn-58Bi (melting point 139 ° C.), Sn-9.0Zn (melting point 199 ° C.), Sn-3.5Ag-0.5Bi-3.0In (melting point 193 ° C.), Au-20Sn (melting point 280 ° C.), etc. Is mentioned.

In the present invention, a metal foil having a desired melting point and composition can be used as appropriate according to the heat resistance of the rigid substrate 20 or the flexible substrate 30 to be connected. For example, in order to prevent the rigid substrate 20 or the flexible substrate 30 from being damaged by thermal history, the melting point is 330 ° C. or lower (more preferably 300 ° C. or lower, particularly preferably 280 ° C. or lower, more preferably 260 ° C. or lower). It is preferable to use a certain metal foil. In addition, melting | fusing point of metal foil can be measured with a differential scanning calorimeter (DSC).

  The thickness of the metal foil can be appropriately selected according to the gap between the rigid substrate 20 and the flexible substrate 30 facing each other, the separation distance between adjacent terminals, and the like. For example, the thickness of the metal foil is 0.5 μm or more. Preferably, it is 3 μm or more, more preferably 5 μm or more, more preferably 100 μm or less, more preferably 50 μm or less, and particularly preferably 20 μm or less. preferable. When the thickness of the metal foil is less than the lower limit, the number of unconnected terminals tends to increase due to insufficient metal foil.On the other hand, when the upper limit is exceeded, bridging occurs between adjacent terminals due to surplus metal foil, which tends to cause short circuit. is there.

  The method for producing the metal foil is not particularly limited, and examples thereof include a method for producing from a lump such as an ingot by rolling, a method for forming a metal foil layer by direct vapor deposition, sputtering, plating, etc. on the resin composition layer. In addition, there is no particular limitation on a method for producing a metal foil having a repetitive pattern. However, a method of punching a metal foil into a predetermined pattern, a method of forming a predetermined pattern by etching, or a shielding plate or a mask is used. The method of forming by vapor deposition, sputtering, plating, etc. is mentioned.

The content of the metal foil is preferably 5% by weight or more, more preferably 20% by weight or more, and particularly preferably 30% by weight or more with respect to the total weight of the conductive connecting material. Moreover, less than 100 weight% is preferable, 80 weight% or less is more preferable, and 70 weight% or less is especially preferable. If the content of the metal foil is less than the above lower limit, unconnected terminals may increase due to insufficient solder or tin. On the other hand, if the content of the metal foil exceeds the above upper limit, bridging is likely to occur between adjacent terminals due to excessive solder or tin.

  Or you may define the compounding quantity of metal foil by the volume ratio with respect to a conductive connection material. For example, the blending amount of the metal foil is preferably 1% by volume or more, more preferably 5% by volume or more, and particularly preferably 10% by volume or more with respect to the conductive connection material. Moreover, it is preferable that it is 90 volume% or less, It is more preferable that it is 80 volume% or less, It is especially preferable that it is 70 volume% or less. When the blending amount of the metal foil is less than the lower limit, unconnected terminals tend to increase due to insufficient metal foil. On the other hand, when the upper limit is exceeded, there is a tendency that bridging is likely to occur between adjacent terminals due to surplus metal foil.

(3) Form of conductive connection material In the present invention, the form of the conductive connection material can be appropriately selected according to the form of the resin composition. For example, when the resin composition is liquid, the resin composition is applied on both sides of a metal foil, or the resin composition is applied on a release substrate such as a polyester sheet, and semi-cured at a predetermined temperature (B-stage) For example, a film obtained by drying and forming a film and pasting metal foils together to form a film can be used as the conductive connection material. When the resin composition is in a solid state, a varnish of the resin composition dissolved in an organic solvent is applied onto a release substrate such as a polyester sheet and dried at a predetermined temperature, and then a metal foil is laminated or vapor deposited. A film formed using the above method can be used as a conductive connection material.

  In addition, the conductive connection material of the present invention and the metal foil used therefor can be embossed to improve contact with the terminal.

The thickness of the conductive connecting material of the present invention is not particularly limited, but is preferably 1 μm or more, more preferably 3 μm or more, particularly preferably 5 μm or more, and preferably 200 μm or less. More preferably, it is 150 μm or less.
It is especially preferable that it is 00 micrometers or less. When the thickness of the conductive connecting material is within the above range, the periphery of the joint can be sufficiently reinforced, the joint can be protected from external stress, and insulation between adjacent terminals can be ensured. it can.

Next, a method for manufacturing the conductive connection material will be described.
When the resin composition used in the present invention is liquid at 25 ° C., for example, the metal foil is dipped in the liquid resin composition, and the liquid resin composition is adhered to both surfaces of the metal foil, so that the conductive connection of the present invention is performed. The material can be manufactured. When the thickness of the resin composition needs to be controlled, it is prepared by a method in which a metal foil immersed in a liquid resin composition is passed through a bar coater having a certain gap or a method in which a liquid resin composition is sprayed with a spray coater or the like. can do.

  Moreover, when a resin composition is a film form at 25 degreeC, a conductive connection material can be manufactured as follows, for example. First, a varnish of a resin composition dissolved in an organic solvent is applied on a release substrate such as a polyester sheet, dried at a predetermined temperature to form a film, and a film-like resin composition is produced. Next, two resin compositions formed on the release substrate were prepared, and the resin composition was placed on top and bottom of the metal foil by laminating with a hot roll with the metal foil sandwiched between the resin composition / metal. A three-layer conductive connecting material made of a foil / resin composition can be produced. In addition, a two-layer conductive connecting material composed of a resin composition / metal foil can be produced by arranging the resin composition on one side of the metal foil by the above-described laminating method.

  When using a wound metal foil, the film-shaped resin composition is laminated on the upper and lower sides or one side of the metal foil with a hot roll, using the metal foil as a base substrate, so that a wound conductive film is used. A connection material can also be obtained. Furthermore, when using a wound metal foil, it is possible to produce a wound conductive connecting material by directly applying a varnish-like resin composition to the upper or lower side or one side of the metal foil and volatilizing the solvent. it can.

When producing conductive connection materials using patterned metal foil, for example, place metal foil on the release substrate, half-cut the metal foil with a mold from the metal foil side, and remove excess metal foil. By removing, a patterned metal foil is produced, and the film-like resin composition may be laminated with a hot roll. When the resin composition is provided on both surfaces of the patterned metal foil, the release substrate is peeled off, and the film-shaped resin composition is formed on the surface of the patterned metal foil opposite to the surface on which the resin composition is formed. What is necessary is just to laminate the thing further.
In addition, the manufacturing method of a conductive connection material is not restrict | limited to the said method. The manufacturing method of the conductive connection material can be appropriately selected by those skilled in the art according to the purpose and application.

The conductive connecting material 70 as described above is used for forming the joint portion 225 and the reinforcing portion 226 included in the electronic component 10.
The method for manufacturing an electronic component of the present invention is applied to the formation of the joint portion 225 and the reinforcing portion 226 using the conductive connection material 70.

<Method for Manufacturing Electronic Component of the Present Invention>
Below, the case where the junction part 225 and the reinforcement part 226 are formed first by applying the manufacturing method of the electronic component of this invention is explained in full detail.

  FIG. 2 shows a method of manufacturing an electronic component according to the present invention, in which a terminal 21 included in a rigid substrate 20 and a terminal 31 included in a flexible substrate 30 are electrically connected by a joint portion 225. 6 is a longitudinal sectional view for explaining a method of manufacturing the electronic component 10 in which a reinforcing portion 226 is formed on the periphery of the joint portion 225. FIG. In the following description, the upper side in FIG. 2 is referred to as “upper” and the lower side is referred to as “lower”.

  The electronic component manufacturing method described below includes a first step of preparing a first substrate (hereinafter, rigid substrate 20 in the present embodiment) and a second substrate (hereinafter, flexible substrate 30 in the present embodiment). A conductive connecting material having a laminated structure composed of a resin composition and a metal foil selected from solder foil or tin foil is interposed between the first substrate and the second substrate; The first terminal of the first substrate and the second terminal of the second substrate are positioned so that the second terminals of the second substrate correspond to each other, and the first substrate / second substrate in which the first substrate and the second substrate are stacked The second step of obtaining the substrate laminate and heating the first substrate / second substrate laminate to melt the metal foil, and the first terminal of the first substrate and the second of the second substrate After the metal foil is agglomerated between the two terminals, the joint is formed by solidifying. A third step of forming a reinforcing layer made of the resin composition on the periphery of the joint portion, and a solidified product of the aggregate obtained by curing or solidifying the reinforcing layer and melting the metal foil, And a second step of obtaining a first substrate / second substrate assembly in which the second terminal of the second substrate and the second terminal of the second substrate are electrically connected.

  In addition, when forming the junction part 225 and the reinforcement part 226, when the resin composition layer 71 with which the electrically conductive connection material 70 is provided is comprised with a curable resin composition, and the case where it is comprised with a thermoplastic resin composition. The formation method is slightly different. Therefore, below, the case where the resin composition layer 71 is comprised with a curable resin composition is made into 1st Embodiment, and the case where it is comprised with a thermoplastic resin composition is demonstrated for every embodiment as 2nd Embodiment. .

<First Embodiment>
[1A] First Step First, as shown in FIG. 2A, a rigid substrate 20 (first substrate) and a flexible substrate 30 (second substrate) in which a semiconductor component 40 is electrically connected by bumps 50. ). At this time, the gap between the rigid substrate 20 and the semiconductor component 40 is preferably sealed with a sealing material 60. Thereby, the effect of protecting the circuit surface (surface in which the bump 50 is formed) of the electronic component 40 and preventing the bump 50 from being cracked can be obtained.

  In this embodiment, as shown to Fig.2 (a), the rigid board | substrate 20 and the flexible substrate 30 are provided in those circuit surfaces, respectively, The some 1st terminal 21 and 2nd terminal which are connected to an individual circuit 31.

[1B] Second Step Next, as shown in FIG. 2B, a resin composition 71 and a metal foil 72 selected from solder foil or tin foil are provided between the rigid substrate 20 and the flexible substrate 30. The conductive connection material 70 having a laminated structure is interposed, and the first terminal 21 included in the rigid substrate 20 and the second terminal 31 included in the flexible substrate 30 are positioned so as to correspond to each other. A rigid substrate / flexible substrate laminate 240 in which 30 is laminated is obtained.

The method for forming the conductive connecting material 70 on the first terminal 21 side is not particularly limited, and examples thereof include a laminating method and a thermocompression bonding method. Bubbles are formed at the interface between the rigid substrate 20 and the conductive connecting material 70. A method using vacuum laminating that can prevent entrainment is preferred.

In this embodiment, the conductive connection material 70 is provided alone on the first terminal 21 side of the rigid substrate 20, but may be provided alone on the second terminal 31 side of the flexible substrate 30. The conductive connection may be provided on both the first terminal 21 side of the rigid substrate 20 and the second terminal 31 side of the flexible substrate 30, or the resin composition 71 is laminated only on one side of the metal foil 72. The material 70 is provided on the first terminal 21 side of the rigid substrate 20 on one side, and the resin substrate 71 provided only on the second terminal 31 side of the flexible substrate is bonded to form a structure of the conductive connection material 70. Also good. From the viewpoint of simplifying the process in the method of manufacturing an electronic component, it is preferable to provide the conductive connection material 70 on one of the first terminal 21 and the second terminal 31. From the viewpoint of improving the adhesion of the rigid substrate 20 / flexible substrate 30 assembly 250, it is preferable to provide the conductive connection material 70 on both the circuit surface 21 and the circuit surface 31.

Next, as shown in FIG. 2B, the rigid board 20 provided with the conductive connection material 70 on the first terminal 21 side and the flexible board 30 having the second terminal are connected to the first terminal 21. The rigid substrate 20 and the flexible substrate 30 are positioned so that the second substrate 31 and the second terminal 31 face each other, and the rigid substrate / flexible substrate laminate 240 is obtained. That is, the rigid substrate 20 and the flexible substrate 30 are disposed in a state where the conductive connection material 70 is interposed between the circuit surface 21 and the circuit surface 31.

[1C] Third Step Next, as shown in FIG. 2C, the rigid substrate / flexible substrate laminate 240 is heated to melt the metal foil, and the first terminal 21 of the rigid substrate 20 The metal foil 72 is aggregated between the second terminals 31 of the flexible substrate 30 and then solidified. Further, the resin composition 71 forms a reinforcing portion 226 at the peripheral edge of the joint portion 225, thereby forming the metal foil. Thus, a rigid substrate / flexible substrate assembly 250 in which the first terminal 21 of the rigid substrate 20 and the second terminal 31 of the flexible substrate 30 are electrically connected is obtained. At this time, a reinforcing portion 226 and a gap portion 227 exist between the rigid substrate 20 and the flexible substrate 30.

The temperature for heating the rigid substrate / flexible substrate laminate 240 is preferably 5 ° C. or higher, more preferably 10 ° C. or higher, more preferably 20 ° C. or higher, more preferably 30 ° C. or higher than the melting point of the metal foil. Temperature is particularly preferred.
Specifically, the heating temperature varies depending on the constituent material of the metal foil and the constituent material of the conductive connecting material 70, but is preferably about 100 to 260 ° C, more preferably about 130 to 250 ° C. preferable.

The rigid substrate / flexible substrate laminate 240 may be heated at a predetermined single temperature, for example, step cure by heating at 180 ° C. for 100 seconds and then heating at 250 ° C. for 100 seconds, or 180 ° C. After 10 seconds of thermocompression bonding, post-curing may be performed by oven-curing at 240 ° C. for 10 minutes. Thereby, the metal foil can be reliably electrically connected by metal bonding between the first terminal and the second terminal, and the bonding portion 225 having low connection resistance and high connection reliability can be formed. Can do.

Further, by heating the rigid substrate / flexible substrate laminate 240 while controlling the gap in the thickness direction to be constant, the metal foil is made to be the first terminal 21 and the flexible substrate 30 of the rigid substrate 20. It can be made to aggregate more efficiently by making it contact the surface of the second terminal 31.
A method for performing the control such that the gap is constant is not particularly limited, and can be performed by using a flip chip bonder or the like.

  Thereby, metal foil can be melted. As a result, the molten metal foil moves through the conductive connection material 70 and aggregates in a self-aligned manner on the surfaces of the first terminal 21 and the second terminal 31. Thereafter, the aggregated aggregate is solidified, and the first terminal and the second terminal can be electrically connected by the joint portion 225 formed of the solidified aggregate.

Further, when the metal foil 72 is melted by the resin composition 71 of the conductive connection material 70, the reinforcing portion 226 and the gap portion 227 are formed between the terminals. As a method for calculating the volume of the resin composition 71 necessary for forming the reinforcing portion 226 at the periphery of the terminal and the joint portion 225, for example, the following method can be used. First, the rigid substrate 20 is calculated from the distance between the terminals when the first terminal 21 and the second terminal 31 are connected from the volume of the metal foil 72 which is a constituent material of the joint portion 225 and the area where the conductive connection material 70 is laminated. And the volume V1 which the gap | interval of the flexible substrate 30 forms is calculated. Next, the sum V2 of the volumes of the terminal 21, the terminal 31, and the joint portion 225 is calculated. Next, by calculating the difference between V1 and V2, the gap V3 between the rigid substrate 20 and the flexible substrate 30 after the rigid substrate 20 and the flexible substrate 30 are electrically connected by the joint portion 225 is calculated.
The volume of the resin composition 71 necessary for forming the reinforcing portion 226 and the gap portion 227 can be calculated based on V3, and the conductive material 70 having a thickness smaller than the volume of V3 is applied. Moreover, although the reinforcement part 226 can be formed by forming the space | gap part 227 with the gas and the water | moisture content which generate | occur | produce by heating the resin composition 71, the formation method in particular of the reinforcement part 226 is not restrict | limited.

Next, the evaluation method of the reinforcement part 226 which concerns on this invention is demonstrated using FIG.
As shown in FIG. 3A, when the cross-sectional area S1 of the gap portion 228 of the rigid substrate / flexible substrate assembly 250 and the cross-sectional area S2 of the reinforcing portion 226 as shown in FIG. By calculating / S1, the reinforcing portion 226 can be evaluated. As shown in FIG. 3C, the cross-sectional areas S1 and S2 are calculated by observing a cross section of a line (AA ′) connecting the central portions of adjacent terminals 21 and performing image processing. Can be calculated.

  The S2 / S1 is preferably 0.1 to 0.9, more preferably 0.2 to 0.8, and particularly preferably 0.3 to 0.7. As a result, it is possible to prevent cracks in the joint portion 225 of the rigid substrate / flexible substrate assembly 250 after the thermal cycle test and separation from occurring at the interface between the terminal 21 or 31 and the joint portion 225.

[1D] Fourth Step Subsequently, the hardening of the reinforcing portion 226 is completed after the melting of the metal foil, so that the melt of the metal foil between the rigid substrate 20 and the flexible substrate 30 is other than the region where the melt is agglomerated. The reinforcing portion 226 made of a cured product or a solidified product of the resin composition 71 can be formed in the region of the above, and the terminal 21, the terminal 31, and the joint portion 225 are protected from external stress by the reinforcing portion 226. In addition, the insulation between adjacent terminals can be secured.

  The hardening of the reinforcing part 226 can be appropriately set according to the composition of the resin composition 71 constituting the reinforcing part 226, but is preferably at least 5 ° C. lower than the heating temperature in the heating step, It is particularly preferable that the temperature is 10 ° C lower. Specifically, it is preferably 100 ° C. or higher, more preferably 120 ° C. or higher, particularly preferably 130 ° C. or higher, and most preferably 150 ° C. or higher. Further, it is preferably 300 ° C. or lower, more preferably 260 ° C. or lower, particularly preferably 250 ° C. or lower, and most preferably 240 ° C. or lower. When the curing temperature is within the above range, the conductive connecting material 70 is not thermally decomposed, and the reinforcing portion 226 can be sufficiently cured.

As described above, after the molten metal foil 72 is aggregated, the aggregated aggregate is solidified, and then the reinforcing portion 226 is cured. As a result, the rigid substrate 20 and the flexible substrate 30 are fixed to each other through the joint portion 225 and the reinforcing portion 226, and the first terminal 21 of the rigid substrate 20 and the second terminal 31 of the flexible substrate 30 are electrically connected. A rigid substrate / flexible substrate assembly 250 connected to the substrate can be formed. In addition, since the step of filling the gap between the rigid substrate 20 and the flexible substrate 30 with a resin such as an underfill material can be omitted, productivity can be improved.

  Here, in the present invention, the first terminal 21 of the rigid substrate 20 and the second terminal 31 of the flexible substrate 30 are electrically connected via a solidified material such as the joint 225. For this reason, when the electronic component 10 to be described later is driven, even if the joint portion 225 expands due to heat generated by the rigid substrate 20 or the flexible substrate 30, the reinforcing portion 226 made of the resin composition 71 is disconnected. Therefore, stable conduction can be obtained between the first terminal 21 of the rigid board 20 and the second terminal 31 of the flexible board 30. That is, an electrical connection excellent in connection reliability can be obtained between the first terminal 21 of the rigid substrate 20 and the second terminal 31 of the flexible substrate 30.

  Although the thickness (average) of the junction part 225 is not specifically limited, It is preferable that it is about 3-200 micrometers, and it is more preferable that it is about 5-150 micrometers. Thus, the thickness of the rigid substrate / flexible substrate assembly 250 can be reduced by reducing the distance between the rigid substrate 20 and the flexible substrate. As a result, the overall thickness of the electronic device including the electronic component 10 can be reduced, and further the weight of the electronic device can be reduced. Furthermore, since the distance between the first terminal 21 and the second terminal 31 can be reduced, the speed of the signal can be increased.

Second Embodiment
Next, the case where the resin composition 71 is comprised with a thermoplastic resin composition is similarly demonstrated using FIG.

[2A] First Step First, the same rigid substrate 20 and flexible substrate 30 as those in the first embodiment are prepared.

[2B] Second Step As in the first embodiment, the resin composition 71 and the solder foil or tin foil are selected between the first terminal 21 of the rigid substrate 20 and the second terminal 31 of the flexible substrate 30. The conductive connection material 70 having a laminated structure composed of the metal foil 72 is interposed, and the first terminal 21 included in the rigid substrate 20 and the second terminal 31 included in the flexible substrate 30 are positioned so as to correspond to each other. A rigid substrate / flexible substrate laminate in which the rigid substrate 20 and the flexible substrate 30 are laminated is obtained.

  Here, the method of interposing the conductive connection material 70 and the method of positioning the rigid substrate 20 and the flexible substrate 30 can be performed by the same method as in the first embodiment.

[2C] Third Step Next, as shown in FIG. 2C, the rigid substrate / flexible substrate laminate 240 is heated to melt the metal foil 72 and the first terminal 21 of the rigid substrate 20. The metal foil 72 is agglomerated between the first substrate 31 and the second terminal 31 of the flexible substrate 30 and then solidified. Further, the reinforcing portion 226 made of the resin composition 71 is solidified, and the rigid substrate 20 and the flexible substrate are solidified. The rigid substrate in which the first terminal 21 of the rigid substrate 20 and the second terminal 31 of the flexible substrate 30 are electrically connected to each other by the solidified product of the agglomerates in which the metal foil 72 is melted. / The flexible substrate assembly 250 is obtained.

  The conditions and method for heating the rigid substrate / flexible substrate laminate 240 are not particularly limited, and the same conditions and method as in the first embodiment can be used.

[2D] The solidification of the reinforcing portion 226 made of the resin composition 71, which is performed in the fourth step, can be performed by cooling and solidifying the conductive connection material heated and melted in the heating step. Cooling and solidification of the conductive connecting material can be appropriately set according to the composition of the resin composition, and is not particularly limited, but may be a method by natural cooling or a method such as blowing cold air. .

  The solidification temperature of the resin composition 71 is not particularly limited, but is preferably lower than the melting point of the metal foil 72. More specifically, the solidification temperature of the thermoplastic resin composition is preferably 10 ° C. or more lower than the melting point of the metal foil 72, and particularly preferably 20 ° C. or lower. The solidification temperature of the resin composition 71 is preferably 50 ° C. or higher, particularly preferably 60 ° C. or higher, and further preferably 100 ° C. or higher. When the solidification temperature of the resin composition 71 is within the above range, the reinforcing portion 226 can be reliably formed, and the reinforcing portion 226 can have desired heat resistance. For this reason, while being able to protect the terminal 21, the terminal 31, and the junction part 225 from external stress, the insulation between adjacent terminals can be ensured.

  The thickness of the joint portion 225 is not particularly limited, but is preferably the same as in the first embodiment. Thus, by reducing the distance between the rigid substrate 20 and the flexible substrate 30, the thickness of the rigid substrate / flexible substrate assembly 250 can be reduced.

  As described above, after the molten metal foil is agglomerated, the agglomerated aggregate is solidified, and then the reinforcing portion 226 composed of the resin composition 71 is cured or solidified. As a result, the rigid substrate 20 and the flexible substrate 30 are fixed to each other through the joint portion 225 and the reinforcing portion 226, and the first terminal 21 of the rigid substrate 20 and the second terminal 31 of the flexible substrate 30 are electrically connected. A rigid substrate / flexible substrate assembly 250 connected to the substrate can be formed. In addition, since the step of filling the gap between the rigid substrate 20 and the flexible substrate 30 with a resin such as an underfill material can be omitted, productivity can be improved.

  Here, in the present invention, the first terminal 21 of the rigid substrate 20 and the second terminal 31 of the flexible substrate 30 are electrically connected via a solidified material such as the joint 225. Therefore, when the electronic component 10 is driven, even if the joint portion 225 expands due to heat generated by the rigid substrate 20 or the flexible substrate 30, the electrical connection of the reinforcing portion 226 made of the resin composition 71 is cut off. This can be suitably prevented, and stable conduction between the first terminal 21 of the rigid substrate 20 and the second terminal 31 of the flexible substrate 30 can be obtained. That is, electrical connection with excellent connection reliability can be obtained between the first terminal 21 of the rigid substrate 20 and the second terminal 31 of the flexible substrate 30.

As mentioned above, although the manufacturing method and electronic component of the electronic component of the present invention, the manufacturing method of the electronic device, and the electronic device were explained, the present invention is not limited to these.
For example, the configuration of each part of the conductive connection material according to the present invention can be replaced with any component that can exhibit the same function, or can be added with any configuration.
Moreover, arbitrary processes may be added to the method for manufacturing an electronic component and the method for manufacturing an electronic device of the present invention as necessary.
Further, in the first embodiment and the second embodiment, the first substrate (rigid substrate 20) and the second substrate (flexible substrate 30) are electrically connected by being fixed by the joint portion 225 and the reinforcing portion 226. However, the present invention is not limited to this case, and examples of the first substrate and the second substrate include a rigid substrate, an organic substrate, a ceramic substrate, Examples of the substrate include a semiconductor wafer, a semiconductor chip, a capacitor, and a resistor chip.

  The electronic component 10 manufactured by the electronic component manufacturing method of the present invention includes, for example, a mobile phone, a digital camera, a video camera, a car navigation system, a personal computer, a game machine, a liquid crystal television, a liquid crystal display, an organic electroluminescence display, It can be widely used in printers and the like.

  The method for manufacturing an electronic component of the present invention can be suitably used when the first substrate and the second substrate are electrically connected and the first substrate and the second substrate are fixed. By using the electronic component manufacturing method of the present invention, it is possible to realize good electrical connection between the first substrate and the second substrate. In addition, by using the electronic component manufacturing method of the present invention, it is possible to meet the demand for downsizing and thinning of electronic components.

10 Electronic parts 20 Rigid board (first board)
21 First terminal 30 Flexible substrate (second substrate)
31 Second terminal 40 Semiconductor component 50 Bump 70 Conductive connection material 71 Resin composition (layer)
72 Metal foil (layer)
225 Bonding part 226 Reinforcing part 227 Gap part 228 Gap part 240 Rigid board / flexible board laminate 250 Rigid board / flexible board joined body

Claims (7)

A method of manufacturing an electronic component in which a first substrate and a second substrate are stacked and electrically connected,
A first step of preparing a first substrate and a second substrate,
Between the first substrate and the second substrate is interposed a conductive connection material having a laminated structure composed of a resin composition and a metal foil selected from solder foil or tin foil, The first substrate / the first substrate on which the first substrate and the second substrate are stacked by positioning so that the first terminal of the first substrate and the second terminal of the second substrate correspond to each other. A second step of obtaining a second substrate laminate;
The metal foil is melted by heating the first substrate / second substrate laminate, and between the first terminal of the first substrate and the second terminal of the second substrate. A third step of forming a joint portion by aggregating the metal foil and then solidifying and forming a reinforcing portion made of the resin composition on the periphery of the first terminal, the second terminal and the joint portion; ,
The reinforcing portion is cured or solidified, and is a solidified product of the aggregate obtained by melting the metal foil, and the first terminal of the first substrate and the second terminal of the second substrate are electrically connected. A fourth step of obtaining a first substrate / second substrate assembly;
A method for manufacturing an electronic component, comprising:   The relationship of S2 / S1 = 0.1-0.9 is satisfied, where S1 is a cross-sectional area of the gap between the first substrate and the second substrate assembly, and S2 is a cross-sectional area of the reinforcing portion. The manufacturing method of the electronic component of description.   The manufacturing method of the electronic component of Claim 1 or 2 with which the said resin composition contains a thermosetting resin.   The method for manufacturing an electronic component according to claim 1, wherein the resin composition includes a compound having a flux function. The manufacturing method of the electronic component in any one of Claims 1 thru | or 4 with which the said electrically conductive connection material contains the laminated structure which consists of a resin composition layer / metal foil layer / resin composition layer.   The method for manufacturing an electronic component according to claim 1, wherein the conductive connection material includes a laminated structure composed of a resin composition layer / metal foil layer.   An electronic component manufactured by the method for manufacturing an electronic component according to claim 1.

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