JP2020170592A - Conductive material and connection structure - Google Patents

Abstract

To provide a conductive material that can effectively suppress positional deviation of a connection member during its positioning, and can effectively improve cohesiveness of conductive particles during conductive connection.SOLUTION: A conductive material has a thermosetting component, and a plurality of conductive particles. On a non-alkali glass substrate, a screen mesh BS500-16CAL is disposed. By using the conductive material, screen printing is conducted to have a width 100 μm, a length 200 μm, and a thickness 10 μm under the conditions of a temperature 25°C, a clearance 1.5 mm, a squeegee angle 70°, a squeegee pressure 0.15 MPa, and a squeegee rate 60 mm/s, so that a contact angle of the conductive material to the non-alkali glass substrate is 20° or more.SELECTED DRAWING: Figure 1

Description

The present invention relates to a conductive material containing a thermosetting component and conductive particles. The present invention also relates to a connection structure using the above conductive material.

Anisotropic conductive materials such as anisotropic conductive pastes and anisotropic conductive films are widely known. In the anisotropic conductive material, conductive particles are dispersed in the binder. Solder particles are widely used as the conductive particles.

The anisotropic conductive material is used to obtain various connection structures. Examples of the connection using the anisotropic conductive material include a connection between a flexible printed circuit board and a glass substrate (FOG (Film on Glass)), a connection between a semiconductor chip and a flexible printed circuit board (COF (Chip on Film)), and a semiconductor. Examples thereof include a connection between a chip and a glass substrate (COG (Chip on Glass)) and a connection between a flexible printed circuit board and a glass epoxy substrate (FOB (Film on Board)).

With the anisotropic conductive material, for example, when the electrode of the flexible printed circuit board and the electrode of the glass epoxy board are electrically connected, the anisotropic conductive material containing conductive particles is arranged on the glass epoxy substrate. To do. Next, the flexible printed circuit boards are laminated and heated and pressurized. As a result, the anisotropic conductive material is cured, and the electrodes are electrically connected to each other via the conductive particles to obtain a connection structure. Examples of the conductive particles include solder particles and the like.

Patent Document 1 below discloses a conductive resin composition in which metal particles are dispersed in a flow medium and the electrodes are electrically connected to each other. The flow medium includes a first flow medium having a relatively high wettability with the metal particles and a second flow medium having a relatively low wettability with the metal particles. The first flow medium and the second flow medium are dispersed in an incompatible state with each other.

Patent Document 2 below discloses an anisotropic conductive film having a conductive particle-containing layer containing an adhesive layer forming component, a tackifying component, and conductive particles, and a peelable base material. The adhesiveness of the surface of the conductive particle-containing layer on the side in contact with the peelable base material is 2.0 times or more the adhesiveness of the surface on the side opposite to the peelable base material. Further, Patent Document 2 below describes that the pressure-sensitive adhesive component is incompatible with the adhesive layer-forming component. According to Patent Document 2 below, the contact angle when the first solution is dropped onto the peelable substrate is larger than the contact angle when the second solution is dropped on the peelable substrate. Is described. The first solution contains 5 parts by mass of the tackifier component and 95 parts by mass of a mixed solvent of isopropyl alcohol: toluene: pure water at 60:20:20 (mass ratio). The second solution contains 95 parts by mass of the adhesive layer forming component and 400 parts by mass of a mixed solvent of methyl ethyl ketone: toluene: cyclohexanone at 50:40:10 (mass ratio).

JP-A-2007-277526 JP 2015-147832

When making a conductive connection using a conductive material containing conductive particles, the conductive material is arranged on the surface of a first connection target member having a plurality of electrodes above, and the first connection target of the conductive material is arranged. On the surface opposite to the member side, a second connection target member having a plurality of electrodes below may be arranged so that the electrodes face each other, and the upper and lower electrodes may be electrically connected to each other. It is desirable that the conductive particles are arranged between the upper and lower electrodes, and not between the adjacent lateral electrodes. It is desirable that there is no electrical connection between adjacent lateral electrodes.

In recent years, electronic devices have been miniaturized. Along with this, miniaturization of connection target members such as semiconductor chips mounted on electronic devices is also progressing. As the miniaturization of the connection target member (semiconductor chip, etc.) progresses, when the upper and lower electrodes are conductively connected using the conductive material, the connection target member (semiconductor chip, etc.) is placed at a predetermined location on the surface of the conductive material. Must be accurately placed and implemented in. However, when a conventional conductive material is used, the connection target member (semiconductor chip, etc.) cannot be accurately placed at a predetermined position on the surface of the conductive material, and the connection target member (semiconductor chip, etc.) cannot be placed accurately. Misalignment may occur when arranging. If the position shift occurs when the connection target member (semiconductor chip or the like) is arranged, the upper and lower electrodes cannot be conductively connected, and the connection target member (semiconductor chip or the like) may not be mounted. With conventional conductive materials, it is difficult to suppress misalignment when the members to be connected (semiconductor chips, etc.) are arranged.

Further, in order to suppress the positional deviation when the member to be connected (semiconductor chip or the like) is arranged, it is studied to increase the viscosity of the conductive material. However, even with a highly viscous conductive material, it is difficult to sufficiently suppress the misalignment when the connecting target member (semiconductor chip or the like) is arranged. Further, if the viscosity of the conductive material is increased, the conductive particles may not be sufficiently aggregated at the time of conductive connection, and the conductive particles may remain between the adjacent lateral electrodes that should not be connected. As a result, it may not be possible to sufficiently improve the conduction reliability between the electrodes to be connected and the insulation reliability between adjacent electrodes that should not be connected.

An object of the present invention is to provide a conductive material capable of effectively suppressing misalignment when arranging a member to be connected and effectively enhancing the cohesiveness of conductive particles at the time of conductive connection. is there. Another object of the present invention is to provide a connection structure using the above conductive material.

According to a broad aspect of the present invention, it is a conductive material containing a thermosetting component and a plurality of conductive particles, and a screen mesh BS500-16CAL is arranged on a non-alkali glass substrate, and the conductive material is used. When screen printing is performed under the conditions of a temperature of 25 ° C., a clearance of 1.5 mm, a squeegee angle of 70 °, a squeegee printing pressure of 0.15 MPa, and a squeegee speed of 60 mm / s so that the width is 100 μm, the length is 200 μm, and the thickness is 10 μm. Provided are a conductive material in which the contact angle of the conductive material with respect to the non-alkali glass substrate is 20 ° or more.

In certain aspects of the conductive material according to the present invention, the conductive particles include a plurality of rubber particles.

In a specific aspect of the conductive material according to the present invention, the thermosetting component contains an epoxy compound, and the epoxy equivalent of the epoxy compound is 100 g / eq or more and 1000 g / eq or less.

In certain aspects of the conductive material according to the present invention, the conductive particles are solder particles.

In a specific aspect of the conductive material according to the present invention, the conductive material contains a coupling agent, and the coupling agent is contained in 100% by weight of the conductive material in an amount of 3% by weight or less.

In a specific aspect of the conductive material according to the present invention, the viscosity of the conductive material at 25 ° C. is 1 Pa · s or more and 200 Pa · s or less.

In a specific aspect of the conductive material according to the present invention, the viscosity of the conductive material at 60 ° C. is 0.01 Pa · s or more and 50 Pa · s or less.

In certain aspects of the conductive material according to the present invention, the conductive material is a conductive paste.

According to a broad aspect of the present invention, a first connection target member having a first electrode on the surface, a second connection target member having a second electrode on the surface, and the first connection target member. A connecting portion that connects the second connection target member is provided, the material of the connecting portion is the above-mentioned conductive material, and the first electrode and the second electrode are the conductive materials. A connecting structure is provided that is electrically connected by particles.

The conductive material according to the present invention contains a thermosetting component and a plurality of conductive particles. In the conductive material according to the present invention, a screen mesh BS500-16CAL is arranged on a non-alkali glass substrate, and the screen is used under the following conditions so as to have a width of 100 μm, a length of 200 μm, and a thickness of 10 μm. When printed, the contact angle of the conductive material with respect to the non-alkali glass substrate is 20 ° or more. The above conditions are a temperature of 25 ° C., a clearance of 1.5 mm, a squeegee angle of 70 °, a squeegee printing pressure of 0.15 MPa, and a squeegee speed of 60 mm / s. Since the conductive material according to the present invention has the above configuration, it is possible to effectively suppress the positional deviation when the members to be connected are arranged, and the cohesiveness of the conductive particles at the time of conductive connection is effective. Can be enhanced to.

FIG. 1 is a cross-sectional view schematically showing a connection structure obtained by using the conductive material according to the embodiment of the present invention. 2 (a) to 2 (c) are cross-sectional views for explaining each step of an example of a method of manufacturing a connection structure using the conductive material according to the embodiment of the present invention. FIG. 3 is a cross-sectional view showing a modified example of the connection structure. FIG. 4 is a cross-sectional view showing a first example of conductive particles that can be used in the conductive material according to the present invention. FIG. 5 is a cross-sectional view showing a second example of conductive particles that can be used in the conductive material according to the present invention. FIG. 6 is a cross-sectional view showing a third example of conductive particles that can be used in the conductive material according to the present invention.

The details of the present invention will be described below.

(Conductive material)
The conductive material according to the present invention contains a thermosetting component and a plurality of conductive particles. In the conductive material according to the present invention, a screen mesh BS500-16CAL is arranged on a non-alkali glass substrate, and the screen is used under the following conditions so as to have a width of 100 μm, a length of 200 μm, and a thickness of 10 μm. When printed, the contact angle of the conductive material with respect to the non-alkali glass substrate is 20 ° or more. The above conditions are a temperature of 25 ° C., a clearance of 1.5 mm, a squeegee angle of 70 °, a squeegee printing pressure of 0.15 MPa, and a squeegee speed of 60 mm / s.

Since the conductive material according to the present invention has the above configuration, it is possible to effectively suppress the positional deviation when the members to be connected are arranged, and the cohesiveness of the conductive particles at the time of conductive connection is effective. Can be enhanced to.

When a conventional conductive material is used, the connection target member (semiconductor chip, etc.) is accurately placed at a predetermined position on the surface of the conductive material due to an impact or the like when the connection target member such as a semiconductor chip is placed. This may not be possible, and misalignment may occur when the members to be connected (semiconductor chips, etc.) are arranged. If the position shift occurs when the connection target member (semiconductor chip or the like) is arranged, the upper and lower electrodes cannot be conductively connected, and the connection target member (semiconductor chip or the like) may not be mounted. With conventional conductive materials, it is difficult to suppress misalignment when the members to be connected (semiconductor chips, etc.) are arranged.

Further, in the conventional conductive material, a method of increasing the viscosity of the conductive material has been studied in order to suppress the positional deviation when the member to be connected (semiconductor chip or the like) is arranged. However, even with a highly viscous conductive material, it is difficult to sufficiently suppress the misalignment when the connecting target member (semiconductor chip or the like) is arranged. Further, if the viscosity of the conductive material is increased, the conductive particles may not be sufficiently aggregated at the time of conductive connection, and the conductive particles may remain between the adjacent lateral electrodes that should not be connected. As a result, it may not be possible to sufficiently improve the conduction reliability between the electrodes to be connected and the insulation reliability between adjacent electrodes that should not be connected.

The present inventors have found that by using a specific conductive material, a member to be connected such as a semiconductor chip can be accurately arranged at a predetermined position on the surface of the conductive material. In the present invention, since the above configuration is provided, when a conductive material is used to make a conductive connection between the upper and lower electrodes, a member to be connected (semiconductor chip, etc.) is placed at a predetermined position on the surface of the conductive material. It can be placed and implemented accurately. Further, in the present invention, since the above configuration is provided, it is not necessary to excessively increase the viscosity of the conductive material, so that the conductive particles can be effectively aggregated at the time of conductive connection. As a result, the reliability of conduction between the electrodes to be connected and the reliability of insulation between adjacent electrodes that should not be connected can be effectively improved.

In the present invention, the use of a specific conductive material in order to obtain the above effects greatly contributes.

In the conductive material according to the present invention, a screen mesh BS500-16CAL is arranged on a non-alkali glass substrate, and the screen is used under the following conditions so as to have a width of 100 μm, a length of 200 μm, and a thickness of 10 μm. When printed, the contact angle of the conductive material with respect to the non-alkali glass substrate is 20 ° or more. The above conditions are a temperature of 25 ° C., a clearance of 1.5 mm, a squeegee angle of 70 °, a squeegee printing pressure of 0.15 MPa, and a squeegee speed of 60 mm / s. The contact angle of the conductive material with respect to the non-alkali glass substrate is preferably 20 ° or more, more preferably 23 ° or more, preferably 60 ° or less, and more preferably 30 ° or less. The contact angle of the conductive material with respect to the non-alkali glass substrate may be 20 ° or less. When the contact angle of the conductive material with respect to the non-alkali glass substrate is equal to or higher than the lower limit and lower than the upper limit, the displacement of the members to be connected at the time of arrangement can be suppressed more effectively, and at the time of conductive connection The cohesiveness of the conductive particles can be further effectively enhanced.

The non-alkali glass substrate is preferably "EAGLEXG 50 × 0.7-25" manufactured by Corning Inc.

The contact angle of the conductive material with respect to the non-alkali glass substrate can be measured using a contact angle measuring device. Specifically, it can be obtained by drawing a tangent line from the contact point between the screen-printed conductive material and the non-alkali glass substrate and calculating the angle between the tangent line and the non-alkali glass substrate. The contact angle of the conductive material with respect to the non-alkali glass substrate is preferably calculated by averaging the contact angles of 10 points of the screen-printed conductive material. Examples of the contact angle measuring device include "DMo-601" manufactured by KYOUWA.

From the viewpoint of more effectively enhancing the cohesiveness of the conductive particles at the time of conductive connection, the conductive material is preferably liquid at 25 ° C., and preferably a conductive paste. The conductive material is preferably a conductive paste at 25 ° C.

From the viewpoint of further effectively enhancing the cohesiveness of the conductive particles at the time of conductive connection, the viscosity (η25) of the conductive material at 25 ° C. is preferably 1 Pa · s or more, more preferably 5 Pa · s or more. Yes, preferably 200 Pa · s or less, more preferably 100 Pa · s or less. The viscosity (η25) can be appropriately adjusted depending on the type and amount of the compounding components.

The viscosity (η25) can be measured at 25 ° C. and 5 rpm using, for example, an E-type viscometer (“TVE22L” manufactured by Toki Sangyo Co., Ltd.).

The viscosity (η60) of the conductive material at 60 ° C. is preferably 0.01 Pa · s or more, more preferably 1 Pa · s or more, preferably 50 Pa · s or less, and more preferably 10 Pa · s or less. The viscosity (η60) can be appropriately adjusted depending on the type and amount of the compounding components. When the viscosity (η60) is at least the above lower limit and at least the above upper limit, the cohesiveness of the conductive particles at the time of conductive connection can be further effectively enhanced. When the viscosity (η60) is equal to or higher than the lower limit and lower than the upper limit, the insulation reliability between the electrodes can be further effectively enhanced, and the conduction reliability between the electrodes can be further effectively enhanced. it can.

The viscosity (η60) can be measured using STRESSTECH (manufactured by REOLOGICA) or the like under the conditions of strain control 1 rad, frequency 1 Hz, heating rate 20 ° C./min, and measurement temperature range 25 ° C. to 200 ° C. From the obtained measurement results, the viscosity at 60 ° C. is defined as the above viscosity (η60).

The conductive material can be used as a conductive paste, a conductive film, or the like. The conductive paste is preferably an anisotropic conductive paste, and the conductive film is preferably an anisotropic conductive film. The conductive material is a conductive paste from the viewpoint of more effectively suppressing the misalignment when arranging the members to be connected and from the viewpoint of further effectively enhancing the cohesiveness of the conductive particles at the time of conductive connection. Is preferable. The conductive material is preferably used for electrical connection of electrodes. The conductive material is preferably a circuit connection material.

Hereinafter, each component contained in the conductive material will be described.

(Conductive particles)
The conductive material contains a plurality of conductive particles. The conductive particles electrically connect the electrodes of the member to be connected. It is preferable that the conductive particles have solder on the outer surface portion of the conductive portion. The conductive particles may be solder particles formed by soldering. From the viewpoint of further effectively enhancing the conduction reliability and insulation reliability between the electrodes, the conductive particles are preferably solder particles.

The solder particles have solder on the outer surface portion of the conductive portion. In the solder particles, both the central portion and the outer surface portion of the conductive portion are formed of solder. The solder particles are particles in which both the central portion and the conductive outer surface are solder. The conductive particles may have a base material particles and a conductive portion arranged on the surface of the base material particles. In this case, it is preferable that the conductive particles have solder on the outer surface portion of the conductive portion.

The conductive particles preferably have solder on the outer surface portion of the conductive portion, and the base material particles may be solder particles formed by solder. The conductive particles may be solder particles in which both the base material particles and the outer surface portion of the conductive portion are solder.

Compared with the case where the above-mentioned solder particles are used, when the conductive particles having the base particles not formed by the solder and the conductive portions arranged on the surface of the base particles are used, the case is used. It becomes difficult for conductive particles to collect on the electrodes. Further, since the conductive particles have low bondability, the conductive particles that have moved on the electrodes tend to move easily to the outside of the electrodes, and the effect of suppressing the displacement between the electrodes also tends to be low. Therefore, the conductive particles are preferably solder particles formed by soldering.

Next, specific examples of the conductive particles will be described with reference to the drawings.

FIG. 4 is a cross-sectional view showing a first example of conductive particles that can be used in the conductive material according to the present invention.

The conductive particles 21 shown in FIG. 4 are solder particles. The conductive particles 21 are entirely formed of solder. The conductive particles 21 do not have base particles in the core and are not core-shell particles. In the conductive particles 21, both the central portion and the outer surface portion of the conductive portion are formed of solder.

FIG. 5 is a cross-sectional view showing a second example of conductive particles that can be used in the conductive material according to the present invention.

The conductive particles 31 shown in FIG. 5 include base particles 32 and conductive portions 33 arranged on the surface of the base particles 32. The conductive portion 33 covers the surface of the base particle 32. The conductive particles 31 are coated particles in which the surface of the base particles 32 is coated with the conductive portion 33.

The conductive portion 33 has a second conductive portion 33A and a first conductive portion 33B. The conductive particle 31 includes a second conductive portion 33A between the base particle 32 and the first conductive portion 33B. Therefore, the conductive particles 31 are the base particles 32, the second conductive portion 33A arranged on the surface of the base particles 32, and the first conductive portion 33A arranged on the outer surface of the second conductive portion 33A. It includes a conductive portion 33B. The first conductive portion is preferably a solder portion.

FIG. 6 is a cross-sectional view showing a third example of conductive particles that can be used in the conductive material according to the present invention.

The conductive portion 33 of the conductive particles 31 in FIG. 5 has a two-layer structure. The conductive particles 41 shown in FIG. 6 have a conductive portion 42 as a single-layer conductive portion. The conductive particles 41 include base particles 32 and conductive portions 42 arranged on the surface of the base particles 32. The conductive portion is preferably a solder portion.

Hereinafter, other details of the conductive particles will be described.

(Base particle)
Examples of the base material particles include resin particles, inorganic particles other than metal particles, organic-inorganic hybrid particles, and metal particles. The base material particles are preferably base particles excluding metal particles, and more preferably resin particles, inorganic particles excluding metal particles, or organic-inorganic hybrid particles. The base particle may be a core-shell particle having a core and a shell arranged on the surface of the core. The core may be an organic core and the shell may be an inorganic shell.

The base material particles are more preferably resin particles or organic-inorganic hybrid particles, and may be resin particles or organic-inorganic hybrid particles. By using these preferable base material particles, the effects of the present invention can be exhibited more effectively, and more suitable conductive particles can be obtained by electrical connection between the electrodes.

When connecting the electrodes using the conductive particles, the conductive particles are placed between the electrodes and then crimped to compress the conductive particles. When the base material particles are resin particles or organic-inorganic hybrid particles, the conductive particles are easily deformed during the pressure bonding, and the contact area between the conductive particles and the electrode becomes large. Therefore, the conduction reliability between the electrodes is further increased.

Various resins are preferably used as the material for the resin particles. Examples of the material of the resin particles include polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene and polybutadiene; acrylic resins such as polymethylmethacrylate and polymethylacrylate; polyalkylene terephthalate and polycarbonate. , Polyamide, phenol formaldehyde resin, melamine formaldehyde resin, benzoguanamine formaldehyde resin, urea formaldehyde resin, phenol resin, melamine resin, benzoguanamine resin, urea resin, epoxy resin, unsaturated polyester resin, saturated polyester resin, polysulfone, polyphenylene oxide, polyacetal, Polymerization of one or more types of polyimides, polyamideimides, polyether ether ketones, polyether sulfones, divinylbenzene polymers, divinylbenzene-based copolymers, and various polymerizable monomers having ethylenically unsaturated groups. Examples thereof include a polymer obtained by subjecting the mixture. Examples of the divinylbenzene-based copolymer include a divinylbenzene-styrene copolymer and a divinylbenzene- (meth) acrylic acid ester copolymer.

Since resin particles having arbitrary compressive properties suitable for a conductive material can be designed and synthesized, and the hardness of the resin particles can be easily controlled within a suitable range, the material of the resin particles is an ethylenically unsaturated group. It is preferable that the polymer is obtained by polymerizing one type or two or more types of polymerizable monomers having a plurality of types.

When the resin particles are obtained by polymerizing a polymerizable monomer having an ethylenically unsaturated group, the polymerizable monomer having an ethylenically unsaturated group is a non-crosslinkable monomer. Examples thereof include crosslinkable monomers.

Examples of the non-crosslinkable monomer include styrene-based monomers such as styrene and α-methylstyrene; carboxyl group-containing monomers such as (meth) acrylic acid, maleic acid, and maleic anhydride; and methyl ( Meta) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) Alkyl (meth) acrylate compounds such as meta) acrylate and isobornyl (meth) acrylate; oxygen atoms such as 2-hydroxyethyl (meth) acrylate, glycerol (meth) acrylate, polyoxyethylene (meth) acrylate and glycidyl (meth) acrylate. Containing (meth) acrylate compound; nitrile-containing monomer such as (meth) acrylonitrile; acid vinyl ester compound such as vinyl acetate, vinyl butyrate, vinyl laurate, vinyl stearate; unsaturated such as ethylene, propylene, isoprene, and butadiene Hydrocarbons: Halogen-containing monomers such as trifluoromethyl (meth) acrylate, pentafluoroethyl (meth) acrylate, vinyl chloride, vinyl fluoride, and chlorostyrene can be mentioned.

Examples of the crosslinkable monomer include tetramethylol methanetetra (meth) acrylate, tetramethylol methanetri (meth) acrylate, tetramethylol methanedi (meth) acrylate, trimethyl propanetri (meth) acrylate, and dipenta. Elythritol hexa (meth) acrylate, dipenta erythritol penta (meth) acrylate, glycerol tri (meth) acrylate, glycerol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) Polyfunctional (meth) acrylate compounds such as acrylates, (poly) tetramethylene glycol di (meth) acrylates, 1,4-butanediol di (meth) acrylates; triallyl (iso) cyanurate, triallyl trimellitate, divinylbenzene, Examples thereof include silane-containing monomers such as diallyl phthalate, diallyl acrylamide, diallyl ether, γ- (meth) acryloxipropyltrimethoxysilane, trimethoxysilylstyrene, and vinyltrimethoxysilane.

The resin particles can be obtained by polymerizing the polymerizable monomer having an ethylenically unsaturated group by a known method. Examples of this method include a method of suspension polymerization in the presence of a radical polymerization initiator, a method of swelling a monomer together with a radical polymerization initiator using non-crosslinked seed particles, and the like.

When the base material particles are inorganic particles other than metal particles or organic-inorganic hybrid particles, examples of the inorganic material as the material of the base material particles include silica, alumina, barium titanate, zirconia, and carbon black. It is preferable that the inorganic substance is not a metal. The particles formed of the silica are not particularly limited, but for example, after hydrolyzing a silicon compound having two or more hydrolyzable alkoxysilyl groups to form crosslinked polymer particles, firing is performed if necessary. Examples include particles obtained by doing so. Examples of the organic-inorganic hybrid particles include organic-inorganic hybrid particles formed of a crosslinked alkoxysilyl polymer and an acrylic resin.

The organic-inorganic hybrid particles are preferably core-shell type organic-inorganic hybrid particles having a core and a shell arranged on the surface of the core. It is preferable that the core is an organic core. It is preferable that the shell is an inorganic shell. From the viewpoint of further effectively lowering the connection resistance between the electrodes, the base particle is preferably an organic-inorganic hybrid particle having an organic core and an inorganic shell arranged on the surface of the organic core. ..

Examples of the material of the organic core include the material of the resin particles described above.

Examples of the material for the inorganic shell include the above-mentioned inorganic substances as the material for the base particle. The material of the inorganic shell is preferably silica. The inorganic shell is preferably formed by forming a metal alkoxide into a shell-like material by a sol-gel method on the surface of the core and then firing the shell-like material. The metal alkoxide is preferably a silane alkoxide. The inorganic shell is preferably formed of silane alkoxide.

When the base material particles are metal particles, examples of the metal as the material of the metal particles include alloys such as silver, copper, nickel, silicon, gold, titanium, and solder.

The particle size of the base particles is preferably 0.005 μm or more, more preferably 0.01 μm or more, still more preferably 0.5 μm or more, still more preferably 1 μm or more, still more preferably 3 μm or more, and preferably. It is 100 μm or less, more preferably 60 μm or less, still more preferably 50 μm or less, and particularly preferably 40 μm or less. When the particle size of the base material particles is equal to or larger than the above lower limit, the contact area between the conductive particles and the electrodes becomes large, so that the conduction reliability between the electrodes becomes even higher, and they are connected via the conductive particles. The connection resistance between the electrodes can be reduced even more effectively. Further, when the conductive portion is formed on the surface of the base material particles, it becomes difficult to aggregate, and it becomes difficult to form the aggregated conductive particles. When the particle size of the base material particles is not more than the above upper limit, the conductive particles are easily sufficiently compressed, and the connection resistance between the electrodes connected via the conductive particles can be further effectively lowered. it can.

The average particle size of the base particles is particularly preferably 0.005 μm or more and 40 μm or less. When the average particle size of the base particles is within the range of 0.005 μm or more and 40 μm or less, the distance between the electrodes can be made smaller, and even if the thickness of the conductive portion is increased, the small conductive particles Can be obtained.

The particle size of the base material particles indicates the diameter when the base material particles are spherical, and indicates the maximum diameter when the base material particles are not spherical.

The average particle size of the base particles is preferably a number average particle size. The average particle size of the base particles is determined by using a particle size distribution measuring device or the like. The average particle size of the base particles is preferably obtained by observing 50 arbitrary base particles with an electron microscope or an optical microscope and calculating an average value. In observation with an electron microscope or an optical microscope, the particle size of each base particle is determined as the particle size in the equivalent circle diameter. In observation with an electron microscope or an optical microscope, the average particle diameter of any 50 base particles in the equivalent circle diameter is substantially equal to the average particle diameter in the equivalent diameter of the sphere. In the particle size distribution measuring device, the particle size of each base particle is determined as the particle size in the equivalent sphere diameter. The average particle size of the base particles is preferably calculated by a particle size distribution measuring device. When measuring the average particle size of the base particles in the conductive particles, for example, the measurement can be performed as follows.

An embedded resin for conducting a conductive particle inspection is prepared by adding and dispersing the conductive particles to "Technobit 4000" manufactured by Kulzer so that the content of the conductive particles is 30% by weight. A cross section of the conductive particles is cut out using an ion milling device (“IM4000” manufactured by Hitachi High-Technologies Corporation) so as to pass near the center of the conductive particles dispersed in the embedded resin for inspection. Then, using a field emission scanning electron microscope (FE-SEM), the image magnification is set to 25000 times, 50 conductive particles are randomly selected, and the base particles of each conductive particle are observed. To do. The particle size of the base material particles in each conductive particle is measured, and they are arithmetically averaged to obtain the average particle size of the base material particles.

(Conductive part)
The method of forming the conductive portion on the surface of the base material particles and the method of forming the first conductive portion on the surface of the base material particles or on the surface of the second conductive portion are not particularly limited. Examples of the method for forming the conductive portion and the first conductive portion include a method by electroless plating, a method by electroplating, a method by physical collision, a method by mechanochemical reaction, physical vapor deposition or physical adsorption. And a method of coating the surface of the base material particles with a metal powder or a paste containing the metal powder and a binder. The method of forming the conductive portion and the first conductive portion is preferably a method by electroless plating, electroplating or physical collision. Examples of the method by physical vapor deposition include methods such as vacuum vapor deposition, ion plating, and ion sputtering. Further, in the above-mentioned physical collision method, for example, a seater composer (manufactured by Tokuju Kosakusho Co., Ltd.) or the like is used.

The melting point of the base material particles is preferably higher than the melting points of the conductive portion and the first conductive portion. The melting point of the base particles preferably exceeds 160 ° C., more preferably exceeds 300 ° C., further preferably exceeds 400 ° C., and particularly preferably exceeds 450 ° C. The melting point of the base particles may be less than 400 ° C. The melting point of the base particles may be 160 ° C. or lower. The softening point of the base particles is preferably 260 ° C. or higher. The softening point of the base particles may be less than 260 ° C.

The conductive particles may have a single-layer solder portion. The conductive particles may have a plurality of layers of conductive portions (first conductive portion, second conductive portion). That is, in the conductive particles, two or more conductive portions may be laminated. When the conductive portion has two or more layers, it is preferable that the conductive particles have solder on the outer surface portion of the conductive portion. The conductive portion and the first conductive portion preferably have solder, and preferably are solder portions.

The solder is preferably a metal having a melting point of 450 ° C. or lower (low melting point metal). The solder portion is preferably a metal layer (low melting point metal layer) having a melting point of 450 ° C. or lower. The low melting point metal layer is a layer containing a low melting point metal. The solder in the conductive particles and the solder particles are preferably metal particles having a melting point of 450 ° C. or lower (low melting point metal particles). The low melting point metal particles are particles containing a low melting point metal. The low melting point metal means a metal having a melting point of 450 ° C. or lower. The melting point of the low melting point metal is preferably 300 ° C. or lower, more preferably 220 ° C. or lower, still more preferably 190 ° C. or lower.

The melting point of the solder is preferably 100 ° C. or higher, more preferably 105 ° C. or higher, preferably 250 ° C. or lower, and more preferably 245 ° C. or lower. When the melting point of the solder is at least the above lower limit and at least the above upper limit, the cohesiveness of the conductive particles at the time of conductive connection can be further effectively enhanced. When the melting point of the solder is equal to or higher than the lower limit and lower than the upper limit, the conduction reliability can be further effectively enhanced and the insulation reliability can be further enhanced when the electrodes are electrically connected. Can be effectively enhanced.

The melting point of the low melting point metal and the melting point of the solder can be determined by differential scanning calorimetry (DSC). Examples of the differential scanning calorimetry (DSC) device include "EXSTAR DSC7020" manufactured by SII.

Further, it is preferable that the conductive particles have the solder on the outer surface portion of the conductive portion. The solder in the conductive particles preferably contains tin. The tin content is preferably 30% by weight or more, more preferably 40% by weight or more, still more preferably 40% by weight or more, based on 100% by weight of the metal contained in the solder portion and 100% by weight of the metal contained in the solder in the conductive particles. Is 70% by weight or more, particularly preferably 90% by weight or more. When the content of tin contained in the solder in the solder portion and the conductive particles is at least the above lower limit, the conduction reliability between the conductive particles and the electrodes becomes even higher.

The tin content can be determined using a high-frequency inductively coupled plasma emission spectroscopic analyzer (“ICP-AES” manufactured by Horiba, Ltd.) or a fluorescent X-ray analyzer (“EDX-800HS” manufactured by Shimadzu Corporation). Can be measured.

By using the conductive particles having the solder on the outer surface portion of the conductive portion, the solder melts and is bonded to the electrodes, and the solder conducts between the electrodes. For example, the solder and the electrode are likely to come into surface contact rather than point contact, so that the connection resistance is low. Further, by using the conductive particles having the solder on the outer surface portion of the conductive portion, the bonding strength between the solder and the electrode is increased, and as a result, the peeling between the solder and the electrode is more difficult to occur, and the conduction reliability is effective. Will be expensive.

The solder portion and the low melting point metal constituting the solder are not particularly limited. The low melting point metal is preferably tin or an alloy containing tin. Examples of the alloy include tin-silver alloy, tin-copper alloy, tin-silver-copper alloy, tin-bismuth alloy, tin-zinc alloy, tin-indium alloy and the like. The low melting point metal is preferably tin, tin-silver alloy, tin-silver-copper alloy, tin-bismuth alloy, or tin-indium alloy because of its excellent wettability to the electrode. The low melting point metal is more preferably a tin-bismuth alloy or a tin-indium alloy.

The material constituting the solder (solder portion) is preferably a filler material having a liquidus line of 450 ° C. or lower based on JIS Z3001: welding terminology. Examples of the composition of the solder include a metal composition containing zinc, gold, silver, lead, copper, tin, bismuth, indium and the like. A tin-indium type (117 ° C. eutectic) or a tin-bismuth type (139 ° C. eutectic), which has a low melting point and is lead-free, is preferable. That is, the solder preferably does not contain lead, and is preferably a solder containing tin and indium, or a solder containing tin and bismuth.

In order to further increase the bonding strength between the solder and the electrode in the solder part or the conductive particles, the solder in the conductive particles is nickel, copper, antimony, aluminum, zinc, iron, gold, titanium, phosphorus, germanium, tellurium. , Cobalt, bismuth, manganese, chromium, molybdenum, and metals such as palladium may be contained. Further, from the viewpoint of further increasing the bonding strength between the solder and the electrode in the solder portion or the conductive particles, the solder in the conductive particles preferably contains nickel, copper, antimony, aluminum or zinc. From the viewpoint of further increasing the bonding strength between the solder and the electrode in the solder portion or the conductive particles, the content of these metals for increasing the bonding strength is preferably 0 in 100% by weight of the solder in the conductive particles. It is .0001% by weight or more, preferably 1% by weight or less.

The melting point of the second conductive portion is preferably higher than the melting point of the first conductive portion (solder portion). The melting point of the second conductive portion preferably exceeds 160 ° C, more preferably 300 ° C, further preferably 400 ° C, even more preferably 450 ° C, and particularly preferably 500 ° C. Most preferably, it exceeds 600 ° C. Since the first conductive portion (solder portion) has a low melting point, it melts at the time of conductive connection. It is preferable that the second conductive portion does not melt at the time of conductive connection. The conductive particles are preferably used by melting the solder, preferably by melting the first conductive portion (solder portion), and melting the first conductive portion (solder portion). It is preferable that the second conductive portion is used without being melted. Since the melting point of the second conductive portion is higher than the melting point of the first conductive portion (solder portion), the first conductive portion is not melted at the time of conductive connection. Only the (solder part) can be melted.

The absolute value of the difference between the melting point of the first conductive portion (solder portion) and the melting point of the second conductive portion exceeds 0 ° C., preferably 5 ° C. or higher, more preferably 10 ° C. or higher, still more preferable. Is 30 ° C. or higher, particularly preferably 50 ° C. or higher, and most preferably 100 ° C. or higher.

The second conductive portion preferably contains a metal. The metal constituting the second conductive portion is not particularly limited. Examples of the metal include gold, silver, copper, platinum, palladium, zinc, lead, aluminum, cobalt, indium, nickel, chromium, titanium, antimony, bismuth, germanium and cadmium, and alloys thereof. Further, tin-doped indium oxide (ITO) may be used as the metal. Only one kind of the above metal may be used, or two or more kinds may be used in combination.

The metal constituting the second conductive portion is preferably nickel, palladium, copper or gold, more preferably nickel, gold or copper, and even more preferably copper. The conductive particles preferably have a nickel layer, a palladium layer, a copper layer or a gold layer, more preferably have a nickel layer, a gold layer or a copper layer, and further preferably have a copper layer. By using the conductive particles having these preferable conductive portions for the connection between the electrodes, the connection resistance between the electrodes is further lowered. Further, a solder portion can be formed more easily on the surface of these preferable conductive portions.

The thickness of the first conductive portion (solder portion) and the second conductive portion is preferably 0.005 μm or more, more preferably 0.01 μm or more, preferably 10 μm or less, more preferably 1 μm or less, and further. It is preferably 0.3 μm or less. When the thickness of the first conductive portion (solder portion) and the second conductive portion is equal to or higher than the lower limit and lower than the upper limit, sufficient conductivity can be obtained and the conductive particles do not become too hard. , The conductive particles are sufficiently deformed during the connection between the electrodes.

The average particle size of the conductive particles is preferably 0.01 μm or more, more preferably 0.5 μm or more, even more preferably 1 μm or more, still more preferably 3 μm or more, preferably 100 μm or less, more preferably 60 μm or less. It is more preferably 50 μm or less, and particularly preferably 40 μm or less. When the average particle diameter of the conductive particles is equal to or greater than the above lower limit and equal to or less than the above upper limit, the conductive particles can be arranged more efficiently on the electrodes, and a large number of conductive particles are arranged between the electrodes. Is easy, and the continuity reliability is further improved.

The average particle size of the conductive particles is more preferably a number average particle size. The average particle size of the conductive particles can be obtained, for example, by observing 50 arbitrary conductive particles with an electron microscope or an optical microscope, calculating an average value, or performing a laser diffraction type particle size distribution measurement. In observation with an electron microscope or an optical microscope, the particle size of each conductive particle is determined as the particle size in the equivalent circle diameter. In observation with an electron microscope or an optical microscope, the average particle diameter of any 50 conductive particles in the equivalent circle diameter is substantially equal to the average particle diameter in the equivalent diameter of the sphere. In the laser diffraction type particle size distribution measurement, the particle size of each conductive particle is determined as the particle size in the equivalent sphere diameter. The average particle size of the conductive particles is preferably calculated by laser diffraction type particle size distribution measurement.

The coefficient of variation (CV value) of the particle size of the conductive particles is preferably 5% or more, more preferably 10% or more, preferably 40% or less, and more preferably 30% or less. When the CV value of the particle diameter is at least the above lower limit and at least the above upper limit, the conductive particles can be arranged more efficiently on the electrode. However, the CV value of the particle diameter of the conductive particles may be less than 5%.

The CV value (coefficient of variation) of the particle diameter of the conductive particles can be measured as follows.

CV value (%) = (ρ / Dn) × 100
ρ: Standard deviation of particle size of conductive particles Dn: Mean value of particle size of conductive particles

The shape of the conductive particles is not particularly limited. The shape of the conductive particles may be spherical or non-spherical, such as flat.

The content of the conductive particles in 100% by weight of the conductive material is preferably 1% by weight or more, more preferably 2% by weight or more, still more preferably 10% by weight or more, and particularly preferably 20% by weight or more. Is 30% by weight or more, preferably 80% by weight or less, more preferably 60% by weight or less, still more preferably 50% by weight or less. When the content of the conductive particles is not less than the above lower limit and not more than the above upper limit, the conductive particles can be arranged more efficiently on the electrodes, and more conductive particles can be arranged between the electrodes. It is easy and the continuity reliability is further improved. From the viewpoint of further enhancing the conduction reliability, it is preferable that the content of the conductive particles is large.

(Rubber particles)
From the viewpoint of more effectively suppressing the positional deviation when the members to be connected are arranged, the conductive material preferably contains a plurality of rubber particles. It is preferable that the rubber particles do not dissolve in a solvent such as an organic solvent. It is preferable that the rubber particles are incompatible with the components in the conductive material such as the thermosetting component. In the conductive material, the rubber particles are preferably present in a dispersed state. At the time of conductive connection, it is preferable that the rubber particles do not inhibit the aggregation of the conductive particles. When the conductive particles are solder particles, it is preferable that the rubber particles do not inhibit the aggregation of the solder particles. When the conductive particles are solder particles, the rubber particles are incorporated into a solder portion (a solidified solder formed by aggregating the molten solder particles after the solder particles are melted) at the time of conductive connection. It is preferable that there is no soldering. The rubber particles may be particles having a core-shell structure or particles having no core-shell structure. The core-shell structure is a structure including a core and a shell arranged on the surface of the core. When the rubber particles are particles having the core-shell structure, it is preferable that the compound constituting the core and the compound constituting the shell are chemically bonded at the interface between the core and the shell. The chemical bond is preferably a graft bond. Only one type of the rubber particles may be used, or two or more types may be used in combination.

The material of the rubber particles is not particularly limited. The material of the rubber particles may contain a silicone compound or may contain a (meth) acrylic compound. When the rubber particles are particles having the core-shell structure, the core may contain a silicone compound or a (meth) acrylic compound, and the shell may contain a silicone compound or a (meth) acrylic compound. Often, the core and the shell may contain a silicone compound or a (meth) acrylic compound.

Examples of the rubber particles include diene-based rubber particles such as methyl methacrylate-butadiene-styrene copolymer resin (MBS resin), polyurethane resin, silicone resin, (meth) acrylic resin, and acrylonitrile-butadiene-styrene copolymer resin (ABS resin). Rubber polymer; Acrylic rubber polymer such as acrylate-styrene-acrylonitrile copolymer resin (ASA resin), acrylate-methylmethacrylate copolymer resin; Silicone-acrylate-methylmethacrylate copolymer resin, silicone-acrylate Examples thereof include silicone-based rubbery polymers (rubber particles containing silicone compounds) such as -acrylic nitrile-styrene copolymer resin; and modified products of these with maleic anhydride, glycidyl methacrylate and the like. From the viewpoint of more effectively suppressing the positional deviation when the members to be connected are arranged, the rubber particles are preferably a diene-based rubber polymer or a silicone-based rubber polymer, and silicone-acrylate-methyl. More preferably, it is a methacrylate copolymer resin.

The average particle size of the rubber particles is preferably 3 μm or less, more preferably 1 μm or less, still more preferably 0.5 μm or less, still more preferably 0.1 μm or less. The lower limit of the average particle size of the rubber particles is not particularly limited. The average particle size of the rubber particles may be 3 μm or more. When the average particle diameter of the rubber particles is not more than the above upper limit, the misalignment at the time of arranging the members to be connected can be suppressed more effectively. When the average particle size of the rubber particles is not more than the above upper limit, the cohesiveness of the conductive particles at the time of conductive connection can be further effectively enhanced.

The average particle size of the rubber particles is a number average particle size. For the average particle size of the rubber particles, for example, 50 arbitrary rubber particles are observed with an electron microscope or an optical microscope, the average value of the particle size of each rubber particle is calculated, or laser diffraction type particle size distribution measurement is performed. Required by doing. In observation with an electron microscope or an optical microscope, the particle size of each rubber particle is determined as the particle size in the equivalent circle diameter. In observation with an electron microscope or an optical microscope, the average particle diameter of any 50 rubber particles in the circle equivalent diameter is substantially equal to the average particle diameter in the sphere equivalent diameter. In the laser diffraction type particle size distribution measurement, the particle size of each rubber particle is obtained as the particle size in the equivalent sphere diameter. The average particle size of the rubber particles is preferably calculated by laser diffraction type particle size distribution measurement.

In the conductive material, the ratio of the average particle diameter of the rubber particles to the average particle diameter of the conductive particles (average particle diameter of rubber particles / average particle diameter of conductive particles) is preferably 3 or less, more preferably. It is 2 or less, preferably 0.001 or more, and more preferably 0.01 or more. The above ratio (average particle size of rubber particles / average particle size of conductive particles) may be 3 or more. When the above ratio (average particle size of rubber particles / average particle size of conductive particles) is equal to or more than the above lower limit and less than or equal to the above upper limit, misalignment at the time of arranging the members to be connected can be suppressed more effectively. it can. When the above ratio (average particle size of rubber particles / average particle size of conductive particles) is equal to or higher than the above lower limit and lower than the above upper limit, the cohesiveness of the conductive particles at the time of conductive connection can be further effectively enhanced. it can.

In the conductive material, it is preferable that the rubber particles are contained in 100% by weight of the conductive material in an amount of 5% by weight or less, and more preferably 3% by weight or less of the rubber particles are contained in 100% by weight of the conductive material. The content of the rubber particles in 100% by weight of the conductive material may be 5% by weight or more. When the content of the rubber particles in 100% by weight of the conductive material is at least the above lower limit and at least the above upper limit, the misalignment at the time of arranging the members to be connected can be suppressed more effectively. When the content of the rubber particles in 100% by weight of the conductive material is at least the above lower limit and at least the above upper limit, the cohesiveness of the conductive particles at the time of conductive connection can be further effectively enhanced.

(Thermosetting component)
The conductive material according to the present invention contains a thermosetting component. The thermosetting component preferably contains a thermosetting compound. The conductive material may contain a thermosetting compound and a thermosetting agent as thermosetting components. In order to cure the conductive material even more satisfactorily, the conductive material preferably contains a thermosetting compound and a thermosetting agent as thermosetting components. In order to cure the conductive material even more satisfactorily, the conductive material preferably contains a curing accelerator as a thermosetting component.

(Thermosetting component: Thermosetting compound)
The conductive material preferably contains a thermosetting compound. The thermosetting compound is a compound that can be cured by heating. The thermosetting compound is not particularly limited. Examples of the thermosetting compound include oxetane compounds, epoxy compounds, episulfide compounds, (meth) acrylic compounds, phenol compounds, amino compounds, unsaturated polyester compounds, polyurethane compounds, silicone compounds and polyimide compounds. From the viewpoint of further improving the curability and viscosity of the conductive material and further enhancing the conduction reliability, the thermosetting compound is preferably an epoxy compound or an episulfide compound, and more preferably an epoxy compound. The conductive material preferably contains an epoxy compound. Only one type of the thermosetting compound may be used, or two or more types may be used in combination.

The epoxy compound is a compound having at least one epoxy group. Examples of the epoxy compound include bisphenol A type epoxy compound, bisphenol F type epoxy compound, bisphenol S type epoxy compound, phenol novolac type epoxy compound, biphenyl type epoxy compound, biphenyl novolac type epoxy compound, biphenol type epoxy compound, and naphthalene type epoxy compound. , Fluorene type epoxy compound, phenol aralkyl type epoxy compound, naphthol aralkyl type epoxy compound, dicyclopentadiene type epoxy compound, anthracene type epoxy compound, adamantan skeleton epoxy compound, tricyclodecane skeleton epoxy compound, naphthylene ether type Examples thereof include epoxy compounds and epoxy compounds having a triazine nucleus as a skeleton. Only one type of the epoxy compound may be used, or two or more types may be used in combination.

The epoxy compound is liquid or solid at room temperature (23 ° C.), and when the epoxy compound is solid at room temperature, the melting temperature of the epoxy compound is preferably equal to or lower than the melting point of the solder. By using the above-mentioned preferable epoxy compound, the viscosity is high at the stage where the connection target members are bonded, and when acceleration is applied due to an impact such as transportation, the first connection target member and the second connection target member are used. It is possible to suppress the misalignment with the member. Further, the heat at the time of curing can greatly reduce the viscosity of the conductive material, and the aggregation of the conductive particles at the time of conductive connection can be efficiently promoted.

From the viewpoint of further improving the insulation reliability and the conduction reliability, the thermosetting component preferably contains an epoxy compound, and the thermosetting compound is an epoxy compound. It is preferable to include it.

The epoxy equivalent of the epoxy compound is preferable from the viewpoint of more effectively suppressing the misalignment at the time of arranging the members to be connected and from the viewpoint of further effectively enhancing the cohesiveness of the conductive particles at the time of conductive connection. Is 100 g / eq or more, more preferably 200 g / eq or more, preferably 1000 g / eq or less, and more preferably 300 g / eq or less.

From the viewpoint of more effectively arranging the conductive particles on the electrode, the thermosetting compound preferably contains a thermosetting compound having a polyether skeleton.

Examples of the thermosetting compound having a polyether skeleton include a compound having a glycidyl ether group at both ends of an alkyl chain having 3 to 12 carbon atoms, and a polyether skeleton having 2 to 4 carbon atoms. Examples thereof include a polyether type epoxy compound having a structural unit in which 2 to 10 are continuously bonded.

From the viewpoint of further effectively enhancing the heat resistance of the cured product, the thermosetting compound preferably contains a thermosetting compound having an isocyanul skeleton.

Examples of the thermosetting compound having an isocyanul skeleton include a triisocyanurate type epoxy compound, and the TEPIC series (TEPIC-G, TEPIC-S, TEPIC-SS, TEPIC-HP, TEPIC-L, manufactured by Nissan Chemical Industries, Ltd.). TEPIC-PAS, TEPIC-VL, TEPIC-UC) and the like.

From the viewpoint of arranging conductive particles on the electrodes more efficiently, from the viewpoint of further improving the conduction reliability between the upper and lower electrodes to be connected, and further effectively discoloring the thermosetting compound. From the viewpoint of suppression, the thermosetting compound preferably has high heat resistance, and more preferably a novolak type epoxy compound. The novolak type epoxy compound has relatively high heat resistance.

The content of the thermosetting compound in 100% by weight of the conductive material is preferably 5% by weight or more, more preferably 8% by weight or more, still more preferably 10% by weight or more, and preferably 99% by weight or less. It is more preferably 90% by weight or less, further preferably 80% by weight or less, and particularly preferably 70% by weight or less. When the content of the thermosetting compound is at least the above lower limit and at least the above upper limit, the conductive particles are arranged more efficiently on the electrodes, and the insulation reliability between the electrodes is further effectively enhanced. This makes it possible to further effectively improve the reliability of conduction between the electrodes. From the viewpoint of further effectively enhancing the impact resistance, it is preferable that the content of the thermosetting compound is large.

The content of the epoxy compound in 100% by weight of the conductive material is preferably 5% by weight or more, more preferably 8% by weight or more, still more preferably 10% by weight or more, preferably 99% by weight or less, more preferably 99% by weight or less. Is 90% by weight or less, more preferably 80% by weight or less, and particularly preferably 70% by weight or less. When the content of the epoxy compound is not less than the above lower limit and not more than the above upper limit, the conductive particles can be arranged more efficiently on the electrodes, and the insulation reliability between the electrodes can be further effectively enhanced. , Conductivity between electrodes can be improved more effectively. From the viewpoint of further enhancing the impact resistance, it is preferable that the content of the epoxy compound is large.

(Thermosetting component: Thermosetting agent)
The conductive material preferably contains a thermosetting agent. The conductive material preferably contains a thermosetting agent together with the thermosetting compound. The thermosetting agent heat-cures the thermosetting compound. The thermosetting agent is not particularly limited. Examples of the heat curing agent include an imidazole curing agent, a phenol curing agent, a thiol curing agent, an amine curing agent, an acid anhydride curing agent, a thermocation curing agent, a thermal radical generating agent, and the like. Only one type of the thermosetting agent may be used, or two or more types may be used in combination.

From the viewpoint of enabling the conductive material to be cured more quickly at a low temperature, the thermosetting agent is preferably an imidazole curing agent, a thiol curing agent, or an amine curing agent. Further, from the viewpoint of enhancing the storage stability when the thermosetting compound and the thermosetting agent are mixed, the thermosetting agent is preferably a latent curing agent. The latent curing agent is preferably a latent imidazole curing agent, a latent thiol curing agent or a latent amine curing agent. The thermosetting agent may be coated with a polymer substance such as a polyurethane resin or a polyester resin.

The imidazole curing agent is not particularly limited. Examples of the imidazole curing agent include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-phenylimidazolium trimerite, and 2,4-diamino-6. -[2'-Methylimidazolyl- (1')] -ethyl-s-triazine and 2,4-diamino-6- [2'-methylimidazole- (1')]-ethyl-s-triazine isocyanuric acid adduct , 2-Phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4-benzyl-5-hydroxymethylimidazole, 2-palatoryl-4-methyl-5 5-Position of 1H-imidazole in -hydroxymethylimidazole, 2-methitolyl-4-methyl-5-hydroxymethylimidazole, 2-metatruyl-4,5-dihydroxymethylimidazole, 2-palatoryl-4,5-dihydroxymethylimidazole, etc. Examples thereof include an imidazole compound in which the hydrogen in the above is substituted with a hydroxymethyl group and the hydrogen at the 2-position is replaced with a phenyl group or a toluyl group.

The thiol curing agent is not particularly limited. Examples of the thiol curing agent include trimethylolpropane tris-3-mercaptopropionate, pentaerythritol tetrakis-3-mercaptopropionate, and dipentaerythritol hexa-3-mercaptopropionate.

The amine curing agent is not particularly limited. Examples of the amine curing agent include hexamethylenediamine, octamethylenediamine, decamethylenediamine, 3,9-bis (3-aminopropyl) -2,4,8,10-tetraspiro [5.5] undecane, and bis (4). -Aminocyclohexyl) methane, metaphenylenediamine, diaminodiphenylsulfone and the like.

The acid anhydride curing agent is not particularly limited, and any acid anhydride used as a curing agent for a thermosetting compound such as an epoxy compound can be widely used. Examples of the acid anhydride curing agent include phthalic anhydride, tetrahydrophthalic anhydride, trialkyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, and methylbutenyltetrahydrophthalic anhydride. Bifunctional such as phthalic acid derivative anhydride, maleic anhydride, nadic acid anhydride, methylnadic anhydride, glutaric anhydride, succinic anhydride, glycerinbis trimellitic anhydride monoacetate, and ethylene glycolbis trimellitic anhydride. Acid anhydride curing agent, trifunctional acid anhydride curing agent such as trimellitic anhydride, and pyromellitic anhydride, benzophenone tetracarboxylic acid anhydride, methylcyclohexenetetracarboxylic acid anhydride, polyazelineic acid anhydride, etc. Examples thereof include an acid anhydride curing agent having four or more functions.

The thermal cation initiator is not particularly limited. Examples of the thermal cation initiator include an iodonium-based cation curing agent, an oxonium-based cation curing agent, and a sulfonium-based cation curing agent. Examples of the iodonium-based cationic curing agent include bis (4-tert-butylphenyl) iodonium hexafluorophosphate and the like. Examples of the oxonium-based cationic curing agent include trimethyloxonium tetrafluoroborate. Examples of the sulfonium-based cationic curing agent include tri-p-tolylsulfonium hexafluorophosphate.

The thermal radical generator is not particularly limited. Examples of the thermal radical generator include azo compounds and organic peroxides. Examples of the azo compound include azobisisobutyronitrile (AIBN) and the like. Examples of the organic peroxide include di-tert-butyl peroxide and methyl ethyl ketone peroxide.

The reaction start temperature of the thermosetting agent is preferably 50 ° C. or higher, more preferably 70 ° C. or higher, further preferably 80 ° C. or higher, preferably 250 ° C. or lower, more preferably 200 ° C. or lower, still more preferably 150 ° C. Below, it is particularly preferably 140 ° C. or less. When the reaction start temperature of the thermosetting agent is not less than the above lower limit and not more than the above upper limit, the conductive particles are arranged more efficiently on the electrode. From the viewpoint of more efficiently arranging the conductive particles on the electrodes and further effectively enhancing the conduction reliability between the upper and lower electrodes to be connected, the reaction start temperature of the thermosetting agent is set. It is particularly preferable that the temperature is 80 ° C. or higher and 140 ° C. or lower.

From the viewpoint of more efficiently arranging the conductive particles on the electrode, the reaction start temperature of the thermosetting agent is preferably higher than the melting point of the solder, more preferably 5 ° C. or higher, and 10 It is more preferable that the temperature is higher than ° C.

The reaction start temperature of the thermosetting agent means the temperature at which the exothermic peak starts to rise in the DSC.

The content of the thermosetting agent is not particularly limited. With respect to 100 parts by weight of the thermosetting compound, the content of the thermosetting agent is preferably 0.01 parts by weight or more, more preferably 1 part by weight or more, preferably 200 parts by weight or less, more preferably. It is 100 parts by weight or less, more preferably 75 parts by weight or less. When the content of the thermosetting agent is at least the above lower limit, it is easy to sufficiently cure the conductive material. When the content of the thermosetting agent is not more than the above upper limit, it becomes difficult for excess thermosetting agent that was not involved in curing to remain after curing, and the heat resistance of the cured product is further increased.

(Thermosetting component: Curing accelerator)
The conductive material may contain a curing accelerator. The curing accelerator is not particularly limited. The curing accelerator preferably acts as a curing catalyst in the reaction between the thermosetting compound and the thermosetting agent. The curing accelerator preferably acts as a curing catalyst in the reaction with the thermosetting compound. Only one type of the curing accelerator may be used, or two or more types may be used in combination.

Examples of the curing accelerator include phosphonium salt, tertiary amine, tertiary amine salt, quaternary onium salt, tertiary phosphine, crown ether complex, amine complex compound and phosphonium ylide. Specifically, the curing accelerator includes an imidazole compound, an isocyanurate of an imidazole compound, dicyandiamide, a derivative of dicyandiamide, a melamine compound, a derivative of a melamine compound, diaminomaleonitrile, diethylenetriamine, triethylenetetramine, and tetraethylenepentamine. , Amine compounds such as bis (hexamethylene) triamine, triethanolamine, diaminodiphenylmethane, organic acid dihydrazide, 1,8-diazabicyclo [5,4,0] undecene-7, 3,9-bis (3-aminopropyl) -2,4,8,10-Tetraoxaspiro [5,5] undecane, boron trifluoride, boron trifluoride-amine complex compound, triphenylphosphine, tricyclohexylphosphine, tributylphosphine, methyldiphenylphosphine, etc. Organic phosphorus compounds and the like.

The phosphonium salt is not particularly limited. Examples of the phosphonium salt include tetranormal butyl phosphonium bromide, tetranormal butyl phosphonium O, O-diethyldithiophosphate, methyl tributyl phosphonium dimethyl phosphate, tetranormal butyl phosphonium benzotriazole, tetranormal butyl phosphonium tetrafluoroborate, and tetranormal. Butylphosphonium tetraphenylborate and the like can be mentioned.

The content of the curing accelerator is appropriately selected so that the thermosetting compound can be cured well. The content of the curing accelerator with respect to 100 parts by weight of the thermosetting compound is preferably 0.5 parts by weight or more, more preferably 0.8 parts by weight or more, preferably 10 parts by weight or less, more preferably 8 parts by weight. It is less than a part by weight. When the content of the curing accelerator is not less than the above lower limit and not more than the above upper limit, the thermosetting compound can be cured satisfactorily. Further, when the content of the curing accelerator is not less than the above lower limit and not more than the above upper limit, the conductive particles can be arranged more efficiently on the electrodes, and the conduction between the upper and lower electrodes to be connected can be achieved. The reliability can be improved even more effectively.

(flux)
The conductive material may contain a flux. By using the flux, the cohesiveness of the conductive particles at the time of conductive connection can be further effectively enhanced. The above flux is not particularly limited. As the flux, a flux generally used for solder bonding or the like can be used.

The flux includes zinc chloride, a mixture of zinc chloride and an inorganic halide, a mixture of zinc chloride and an inorganic acid, a molten salt, phosphoric acid, a derivative of phosphoric acid, an organic halide, a hydrazine, an amine compound, an organic acid and the like. Examples include pine fat. Only one type of the above flux may be used, or two or more types may be used in combination.

Examples of the molten salt include ammonium chloride and the like. Examples of the organic acid include lactic acid, citric acid, stearic acid, glutamic acid and glutaric acid. Examples of the above-mentioned pine resin include activated pine resin and non-activated pine resin. The flux is preferably an organic acid having two or more carboxyl groups or pine resin. The flux may be an organic acid having two or more carboxyl groups, or may be pine resin. By using an organic acid or pine resin having two or more carboxyl groups, the conduction reliability between the electrodes can be further effectively enhanced.

Examples of the organic acid having two or more carboxyl groups include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid.

Examples of the amine compound include cyclohexylamine, dicyclohexylamine, benzylamine, benzhydrylamine, imidazole, benzimidazole, phenylimidazole, carboxybenzoimidazole, benzotriazole, and carboxybenzotriazole.

The above pine resin is a rosin containing abietic acid as a main component. Examples of the rosins include abietic acid and acrylic-modified rosins. The flux is preferably rosins, more preferably abietic acid. By using this preferable flux, the conduction reliability between the electrodes can be further effectively enhanced.

The active temperature (melting point) of the flux is preferably 50 ° C. or higher, more preferably 70 ° C. or higher, further preferably 80 ° C. or higher, preferably 200 ° C. or lower, more preferably 190 ° C. or lower, still more preferably 160 ° C. or higher. ° C. or lower, more preferably 150 ° C. or lower, even more preferably 140 ° C. or lower. When the active temperature of the flux is not less than the above lower limit and not more than the above upper limit, the flux effect is exhibited more effectively and the solder is arranged more efficiently on the electrode. The active temperature (melting point) of the flux is preferably 80 ° C. or higher and 190 ° C. or lower. The active temperature (melting point) of the flux is particularly preferably 80 ° C. or higher and 140 ° C. or lower.

The melting point of the flux can be determined by differential scanning calorimetry (DSC). Examples of the differential scanning calorimetry (DSC) device include "EXSTAR DSC7020" manufactured by SII.

The active temperature (melting point) of the flux is 80 ° C. or higher and 190 ° C. or lower. Examples of the flux include succinic acid (melting point 186 ° C.), glutaric acid (melting point 96 ° C.), adipic acid (melting point 152 ° C.), and pimeric acid (melting point 104 ° C.). ℃), Dicarboxylic acids such as suberic acid (melting point 142 ° C.), benzoic acid (melting point 122 ° C.), malic acid (melting point 130 ° C.) and the like.

The boiling point of the flux is preferably 200 ° C. or lower.

From the viewpoint of more efficiently arranging the conductive particles on the electrode, the melting point of the flux is preferably higher than the melting point of the solder, more preferably 5 ° C. or higher, and 10 ° C. or higher. Is even more preferable.

From the viewpoint of more efficiently arranging the conductive particles on the electrode, the melting point of the flux is preferably higher than the reaction start temperature of the thermosetting agent, more preferably 5 ° C. or higher, and 10 It is more preferable that the temperature is higher than ° C.

The flux may be dispersed in the conductive material or may be adhered to the surface of the conductive particles.

Since the melting point of the flux is higher than the melting point of the solder, the conductive particles (solder particles) can be efficiently aggregated on the electrode portion. This is because when heat is applied at the time of joining, the thermal conductivity of the electrode portion is higher than that of the connection target member portion around the electrode when the electrode formed on the connection target member is compared with the connection target member portion around the electrode. Because it is higher than the thermal conductivity, the temperature rise of the electrode portion is fast. When the melting point of the conductive particles (solder particles) is exceeded, the inside of the conductive particles (solder particles) dissolves, but the oxide film formed on the surface does not reach the melting point (active temperature) of the flux. , Not removed. In this state, since the temperature of the electrode portion reaches the melting point (active temperature) of the flux first, the oxide film on the surface of the conductive particles (solder particles) that have preferentially moved onto the electrodes is removed, and the conductive particles. (Solder particles) can wet and spread on the surface of the electrode. As a result, conductive particles (solder particles) can be efficiently aggregated on the electrodes.

The flux is preferably a flux that releases cations by heating. The use of a flux that releases cations upon heating allows the conductive particles to be placed more efficiently on the electrodes.

Examples of the flux that releases cations by the heating include the thermal cation initiator (thermal cation curing agent).

From the viewpoint of more efficiently arranging the conductive particles on the electrode, more effectively enhancing the insulation reliability, and further effectively enhancing the conduction reliability, the above-mentioned flux is an acid compound. It is preferably a salt with a base compound.

The acid compound is preferably an organic compound having a carboxyl group. Examples of the acid compound include malonic acid, succinic acid, glutaric acid, adipic acid, pimelli acid, suberic acid, azelaic acid, sebacic acid, citric acid, malic acid, and cyclic aliphatic carboxylic acid, which are aliphatic carboxylic acids. Examples thereof include cyclohexylcarboxylic acid, 1,4-cyclohexyldicarboxylic acid, isophthalic acid which is an aromatic carboxylic acid, terephthalic acid, trimellitic acid, ethylenediamine tetraacetic acid and the like. From the viewpoint of more efficiently arranging the conductive particles on the electrode, more effectively enhancing the insulation reliability, and further effectively enhancing the conduction reliability, the acid compound is glutaric acid. , Cyclohexylcarboxylic acid, or adipic acid is preferred.

The basic compound is preferably an organic compound having an amino group. Examples of the basic compound include diethanolamine, triethanolamine, methyldiethanolamine, ethyldiethanolamine, cyclohexylamine, dicyclohexylamine, benzylamine, benzhydrylamine, 2-methylbenzylamine, 3-methylbenzylamine, and 4-tert-butylbenzylamine. , N-Methylbenzylamine, N-ethylbenzylamine, N-phenylbenzylamine, N-tert-butylbenzylamine, N-isopropylbenzylamine, N, N-dimethylbenzylamine, imidazole compounds, and triazole compounds. .. From the viewpoint of more efficiently arranging the conductive particles on the electrode, more effectively enhancing the insulation reliability, and further effectively enhancing the conduction reliability, the above-mentioned basic compound is benzylamine. Is preferable.

The content of the flux in 100% by weight of the conductive material is preferably 0.5% by weight or more, preferably 30% by weight or less, and more preferably 25% by weight or less. When the content of the flux is not less than the above lower limit and not more than the above upper limit, it becomes more difficult to form an oxide film on the surfaces of the conductive particles and the electrode, and further, oxidation formed on the surfaces of the conductive particles and the electrode. The film can be removed even more effectively.

(Filler)
The conductive material may contain a filler. The filler may be an organic filler or an inorganic filler. By adding the filler, the conductive particles can be more uniformly aggregated on all the electrodes of the substrate.

The conductive material preferably does not contain the filler, or contains the filler in an amount of 5% by weight or less. When the thermosetting compound is used, the smaller the filler content, the easier it is for the conductive particles to move onto the electrodes.

The content of the filler in 100% by weight of the conductive material is preferably 0% by weight (not contained) or more, preferably 5% by weight or less, more preferably 2% by weight or less, still more preferably 1% by weight or less. Is. When the content of the filler is not less than the above lower limit and not more than the above upper limit, the conductive particles are more uniformly arranged on the electrode.

(Coupling agent)
From the viewpoint of more effectively suppressing the displacement of the members to be connected at the time of arrangement and further effectively enhancing the cohesiveness of the conductive particles at the time of conductive connection, the conductive material is a coupling agent. It is preferable to include it.

The coupling agent is not particularly limited. Examples of the coupling agent include a silane coupling agent, a titanium coupling agent, an aluminum coupling agent, and the like. Examples of the silane coupling agent include vinylsilane, aminosilane, imidazolesilane, and epoxysilane. From the viewpoint of more effectively suppressing the displacement of the members to be connected at the time of arrangement and further effectively enhancing the cohesiveness of the conductive particles at the time of conductive connection, the above-mentioned coupling agent is a silane coupling agent. It is preferably an agent or a titanium coupling agent, and more preferably 3-glycidoxypropyltriethoxysilane.

The coupling agent is preferably contained in an amount of 3% by weight or less, and more preferably 1% by weight or less in 100% by weight of the conductive material. The content of the coupling agent in 100% by weight of the conductive material may be 3% by weight or more. When the content of the coupling agent is not less than the above lower limit and not more than the above upper limit, the misalignment at the time of arranging the members to be connected can be suppressed more effectively, and the agglomeration of the conductive particles at the time of conductive connection can be suppressed. The sex can be enhanced even more effectively.

(Other ingredients)
The conductive material may be, for example, a filler, a bulking agent, a softening agent, a plasticizer, a thickener, a thixo agent, a leveling agent, a polymerization catalyst, a curing catalyst, a colorant, an antioxidant, a heat stabilizer, if necessary. , Light stabilizer, UV absorber, lubricant, antistatic agent, flame retardant and other various additives may be contained.

(Connection structure)
The connection structure according to the present invention includes a first connection target member having a first electrode on the surface, a second connection target member having a second electrode on the surface, and the first connection target member. It includes a connecting portion that connects the second connection target member. In the connection structure according to the present invention, the material of the connection portion is the above-mentioned conductive material. In the connection structure according to the present invention, the first electrode and the second electrode are electrically connected by the conductive particles.

In the connection structure according to the present invention, since a specific conductive material is used, the conductive particles are likely to collect between the first electrode and the second electrode, and the conductive particles are efficiently placed on the electrode (line). Can be arranged as a target. Further, it is difficult for some of the conductive particles to be arranged in the region (space) where the electrode is not formed, and the amount of the conductive particles arranged in the region where the electrode is not formed can be considerably reduced. Therefore, the conduction reliability between the first electrode and the second electrode can be improved. Moreover, it is possible to prevent electrical connection between horizontally adjacent electrodes that should not be connected, and it is possible to improve insulation reliability.

Further, in order to efficiently arrange the conductive particles on the electrodes and to considerably reduce the amount of solder arranged in the region where the electrodes are not formed, the conductive material is not a conductive film but a conductive paste. It is preferable to use.

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a cross-sectional view schematically showing a connection structure obtained by using the conductive material according to the embodiment of the present invention.

The connection structure 1 shown in FIG. 1 is a connection connecting the first connection target member 2, the second connection target member 3, the first connection target member 2, and the second connection target member 3. It includes a part 4. The connecting portion 4 is formed of the above-mentioned conductive material. In the present embodiment, the conductive material contains a thermosetting component and a plurality of conductive particles. The thermosetting component contains a thermosetting compound and a thermosetting agent. The conductive particles are solder particles. In this embodiment, a conductive paste is used as the conductive material.

The connecting portion 4 has a solder portion 4A in which a plurality of solder particles are gathered and bonded to each other, and a cured product portion 4B in which a thermosetting component is thermoset.

The first connection target member 2 has a plurality of first electrodes 2a on the surface (upper surface). The second connection target member 3 has a plurality of second electrodes 3a on the surface (lower surface). The first electrode 2a and the second electrode 3a are electrically connected by the solder portion 4A. Therefore, the first connection target member 2 and the second connection target member 3 are electrically connected by the solder portion 4A. In the connecting portion 4, no solder is present in a region (cured product portion 4B portion) different from the solder portion 4A gathered between the first electrode 2a and the second electrode 3a. In a region different from the solder portion 4A (cured product portion 4B portion), there is no solder separated from the solder portion 4A. If the amount is small, the solder may be present in a region (cured product portion 4B portion) different from the solder portion 4A gathered between the first electrode 2a and the second electrode 3a.

As shown in FIG. 1, in the connection structure 1, a plurality of solder particles are gathered between the first electrode 2a and the second electrode 3a, and after the plurality of solder particles are melted, a melt of the solder particles is formed. Soldered and spread on the surface of the electrode and then solidified to form the solder portion 4A. Therefore, the connection area between the solder portion 4A and the first electrode 2a and the solder portion 4A and the second electrode 3a becomes large. That is, by using the solder particles, the solder portion 4A, the first electrode 2a, and the solder are compared with the case where the outer surface portion of the conductive portion is a metal such as nickel, gold, or copper. The contact area between the portion 4A and the second electrode 3a becomes large. Therefore, the continuity reliability and the connection reliability of the connection structure 1 are improved. The flux contained in the conductive material is generally gradually deactivated by heating.

In the connection structure 1 shown in FIG. 1, all of the solder portions 4A are located in facing regions between the first and second electrodes 2a and 3a. In the connection structure 1X of the modified example shown in FIG. 3, only the connection portion 4X is different from the connection structure 1 shown in FIG. The connection portion 4X has a solder portion 4XA and a cured product portion 4XB. Like the connection structure 1X, most of the solder portions 4XA are located in the opposite regions of the first and second electrodes 2a and 3a, and a part of the solder portions 4XA is the first and second electrodes. The electrodes 2a and 3a may protrude laterally from the facing regions. The solder portion 4XA protruding laterally from the facing regions of the first and second electrodes 2a and 3a is a part of the solder portion 4XA, and is not the solder separated from the solder portion 4XA. In the present embodiment, the amount of solder separated from the solder portion can be reduced, but the solder separated from the solder portion may be present in the cured product portion.

If the amount of solder particles used is reduced, it becomes easy to obtain the connection structure 1. If the amount of solder particles used is increased, it becomes easy to obtain the connection structure 1X.

The thickness of the solder portion between the first electrode and the second electrode is preferably 10 μm or more, more preferably 20 μm or more, preferably 100 μm or less, and more preferably 80 μm or less. In the first electrode and the second electrode, the solder wet area (the area in contact with the solder in the exposed area of the electrode 100%) on the surface of the electrode is preferably 50% or more, more preferably 60. % Or more, more preferably 70% or more, and preferably 100% or less. When the solder portion in the connection portion satisfies the above preferred embodiment, the continuity reliability and the insulation reliability can be further effectively improved.

In the connection structures 1 and 1X, when the portions facing each other of the first electrode 2a and the second electrode 3a are seen in the stacking direction of the first electrode 2a, the connection portions 4, 4X and the second electrode 3a. It is preferable that the solder portions 4A and 4XA in the connecting portions 4 and 4X are arranged in 50% or more of the area of 100% of the portions facing each other of the first electrode 2a and the second electrode 3a. .. When the solder portions 4A and 4XA in the connection portions 4 and 4X satisfy the above-mentioned preferable aspects, the continuity reliability can be further improved.

When the portion where the first electrode and the second electrode face each other is seen in the stacking direction of the first electrode, the connection portion, and the second electrode, the first electrode and the first electrode are seen. It is preferable that the solder portion in the connection portion is arranged in 50% or more of the area of 100% of the portions facing the electrodes of 2. When the portion where the first electrode and the second electrode face each other is seen in the stacking direction of the first electrode, the connection portion, and the second electrode, the first electrode and the first electrode are seen. It is more preferable that the solder portion in the connection portion is arranged in 60% or more of the area of 100% of the portions facing the electrodes of 2. When the portion where the first electrode and the second electrode face each other is seen in the stacking direction of the first electrode, the connection portion, and the second electrode, the first electrode and the first electrode are seen. It is more preferable that the solder portion in the connection portion is arranged in 70% or more of the area of 100% of the portions facing the electrodes of 2. When the portion where the first electrode and the second electrode face each other is seen in the stacking direction of the first electrode, the connection portion, and the second electrode, the first electrode and the first electrode are seen. It is particularly preferable that the solder portion in the connection portion is arranged in 80% or more of the area of 100% of the portions facing the electrodes of 2. When the portion where the first electrode and the second electrode face each other is seen in the stacking direction of the first electrode, the connection portion, and the second electrode, the first electrode and the first electrode are seen. It is most preferable that the solder portion in the connection portion is arranged in 90% or more of the area of 100% of the portions facing the electrodes of 2. When the solder portion in the connection portion satisfies the above-mentioned preferred embodiment, the continuity reliability can be further improved.

When the portions facing each other of the first electrode and the second electrode are viewed in a direction orthogonal to the stacking direction of the first electrode, the connection portion, and the second electrode, the first electrode is used. It is preferable that 60% or more of the solder portion in the connection portion is arranged at the portion where the electrode and the second electrode face each other. When the portions facing each other of the first electrode and the second electrode are viewed in a direction orthogonal to the stacking direction of the first electrode, the connection portion, and the second electrode, the first electrode is used. It is more preferable that 70% or more of the solder portion in the connection portion is arranged at the portion where the electrode and the second electrode face each other. When the portions facing each other of the first electrode and the second electrode are viewed in a direction orthogonal to the stacking direction of the first electrode, the connection portion, and the second electrode, the first electrode is used. It is more preferable that 90% or more of the solder portion in the connection portion is arranged at the portion where the electrode and the second electrode face each other. When the portions facing each other of the first electrode and the second electrode are viewed in a direction orthogonal to the stacking direction of the first electrode, the connection portion, and the second electrode, the first electrode is used. It is particularly preferable that 95% or more of the solder portion in the connection portion is arranged at the portion where the electrode and the second electrode face each other. When the portions facing each other of the first electrode and the second electrode are viewed in a direction orthogonal to the stacking direction of the first electrode, the connection portion, and the second electrode, the first electrode is used. It is most preferable that 99% or more of the solder portion in the connection portion is arranged at the portion where the electrode and the second electrode face each other. When the solder portion in the connection portion satisfies the above-mentioned preferred embodiment, the continuity reliability can be further improved.

Next, FIG. 2 describes an example of a method for manufacturing the connection structure 1 using the conductive material according to the embodiment of the present invention.

First, the first connection target member 2 having the first electrode 2a on the surface (upper surface) is prepared. Next, as shown in FIG. 2A, the thermosetting component 11B and the conductive material 11 containing the plurality of solder particles 11A are arranged on the surface of the first connection target member 2 (first step). ). The thermosetting component 11B contains a thermosetting compound and a thermosetting agent.

The conductive material 11 is arranged on the surface of the first connection target member 2 on which the first electrode 2a is provided. After the arrangement of the conductive material 11, the solder particles 11A are arranged both on the first electrode 2a (line) and on the region (space) where the first electrode 2a is not formed. The conductive material may be arranged only on the surface of the first electrode.

The method of arranging the conductive material 11 is not particularly limited, and examples thereof include coating with a dispenser, screen printing, and ejection with an inkjet device.

Further, a second connection target member 3 having the second electrode 3a on the front surface (lower surface) is prepared. Next, as shown in FIG. 2B, in the conductive material 11 on the surface of the first connection target member 2, on the surface of the conductive material 11 opposite to the first connection target member 2 side. The second connection target member 3 is arranged (second step). The second connection target member 3 is arranged on the surface of the conductive material 11 from the second electrode 3a side. At this time, the first electrode 2a and the second electrode 3a are opposed to each other.

In the present embodiment, since a specific conductive material is used, when the second connection target member (semiconductor chip or the like) is arranged in the second step, the second connection target member (semiconductor chip or the like) is used. Etc.) can be accurately placed in a predetermined place on the surface of the conductive material.

Next, the conductive material 11 is heated above the melting point of the solder particles 11A (third step). Preferably, the conductive material 11 is heated above the curing temperature of the thermosetting component 11B (thermosetting compound). At the time of this heating, the solder particles 11A existing in the region where the electrodes are not formed gather between the first electrode 2a and the second electrode 3a (self-aggregation effect). When a conductive paste is used instead of the conductive film, the solder particles 11A are more effectively collected between the first electrode 2a and the second electrode 3a. Further, the solder particles 11A are melted and joined to each other. Further, the thermosetting component 11B is thermoset. As a result, as shown in FIG. 2C, the connecting portion 4 connecting the first connecting target member 2 and the second connecting target member 3 is formed of the conductive material 11. The connecting portion 4 is formed by the conductive material 11, the solder portion 4A is formed by joining the plurality of solder particles 11A, and the cured product portion 4B is formed by thermosetting the thermosetting component 11B. If the solder particles 11A move sufficiently, the solder particles 11A that are not located between the first electrode 2a and the second electrode 3a start moving, and then the first electrode 2a and the second electrode It is not necessary to keep the temperature constant until the movement of the solder particles 11A to and from 3a is completed.

It is preferable not to pressurize in the second step and the third step. In this case, the weight of the second connection target member 3 is added to the conductive material 11. Therefore, when the connecting portion 4 is formed, the solder particles 11A are more effectively gathered between the first electrode 2a and the second electrode 3a. When pressurization is performed in at least one of the second step and the third step, the solder particles 11A tend to gather between the first electrode 2a and the second electrode 3a. Is more likely to be inhibited.

Further, in the present embodiment, since the pressurization is not performed, the first connection target member 2 and the second connection target are in a state where the first electrode 2a and the second electrode 3a are slightly misaligned. Even when the members 3 are overlapped with each other, the slight deviation can be corrected to connect the first electrode 2a and the second electrode 3a (self-alignment effect). This is because the molten solder that is self-aggregated between the first electrode 2a and the second electrode 3a is the solder between the first electrode 2a and the second electrode 3a and other conductive materials. This is because the energy is more stable when the area in contact with the components is the smallest, and the force for forming the aligned connection structure, which is the connection structure with the minimum area, works. At this time, it is desirable that the conductive material is not cured and that the viscosity of the components other than the solder particles of the conductive material is sufficiently low at the temperature and time.

The viscosity (ηmp) of the conductive material at the melting point of the solder is preferably 50 Pa · s or less, more preferably 10 Pa · s or less, further preferably 1 Pa · s or less, preferably 0.1 Pa · s or more, more preferably. Is 0.2 Pa · s or more. When the viscosity (ηmp) is not more than the above upper limit, the conductive particles can be efficiently aggregated at the time of conductive connection. When the viscosity (ηmp) is at least the above lower limit, voids at the connecting portion can be suppressed and the protrusion of the conductive material to other than the connecting portion can be suppressed.

The viscosity (ηmp) of the conductive material at the melting point of the solder is measured as follows.

The viscosity (ηmp) of the conductive material at the melting point of the solder is determined by using STRESSTECH (manufactured by REOLOGICA) or the like, strain control 1 rad, frequency 1 Hz, heating rate 20 ° C./min, measurement temperature range 25 ° C. to 200 ° C. ( However, when the melting point of the solder exceeds 200 ° C., the upper limit of the temperature is set as the melting point of the solder). From the measurement results, the viscosity of the solder at the melting point (° C.) is defined as the above viscosity (ηmp).

In this way, the connection structure 1 shown in FIG. 1 is obtained. The second step and the third step may be continuously performed. Further, after performing the second step, the obtained laminate of the first connection target member 2, the conductive material 11, and the second connection target member 3 is moved to the heating unit to move the third The process may be performed. In order to perform the heating, the laminate may be arranged on the heating member, or the laminate may be arranged in the heated space.

The heating temperature in the third step is preferably 140 ° C. or higher, more preferably 160 ° C. or higher, preferably 450 ° C. or lower, more preferably 250 ° C. or lower, still more preferably 200 ° C. or lower. When the heating temperature in the third step is equal to or higher than the lower limit and lower than the upper limit, the conductive particles can be arranged more efficiently on the electrodes, and the conduction between the upper and lower electrodes to be connected can be achieved. The reliability can be improved even more effectively.

As a heating method in the third step, a method of heating the entire connection structure using a reflow furnace or an oven at a temperature equal to or higher than the melting point of the solder and a temperature higher than the curing temperature of the thermosetting component, or a connection structure. A method of locally heating only the connection portion of the solder is mentioned.

Examples of the appliance used for the method of locally heating include a hot plate, a heat gun for applying hot air, a soldering iron, an infrared heater, and the like.

When locally heating on a hot plate, use a metal with high thermal conductivity directly under the connection, and use a material with low thermal conductivity such as fluororesin in other areas where heating is not preferable. , It is preferable to form the upper surface of the hot plate.

The first and second connection target members are not particularly limited. Specific examples of the first and second connection target members include electronic components such as semiconductor chips, semiconductor packages, LED chips, LED packages, capacitors and diodes, resin films, printed circuit boards, flexible printed circuit boards, and flexible devices. Examples thereof include electronic components such as flat cables, rigid flexible substrates, glass epoxy substrates, and circuit boards such as glass substrates. The first and second connection target members are preferably electronic components.

It is preferable that at least one of the first connection target member and the second connection target member is a resin film, a flexible printed circuit board, a flexible flat cable, or a rigid flexible substrate. It is preferable that at least one of the first connection target member and the second connection target member is a resin film, a flexible printed circuit board, a flexible flat cable, or a rigid flexible substrate. Resin films, flexible printed circuit boards, flexible flat cables, and rigid flexible substrates have the properties of high flexibility and relatively light weight. When a conductive film is used for connecting the members to be connected, the conductive particles tend to be difficult to collect on the electrodes. On the other hand, by using the conductive paste, even if a resin film, a flexible printed circuit board, a flexible flat cable or a rigid flexible substrate is used, the conductive particles are efficiently collected on the electrodes to conduct the conduction between the electrodes. The reliability can be sufficiently improved. When a resin film, a flexible printed circuit board, a flexible flat cable, or a rigid flexible substrate is used, the continuity reliability between the electrodes is improved by not applying pressure, as compared with the case where other members to be connected such as a semiconductor chip are used. The improvement effect can be obtained even more effectively.

Examples of the electrodes provided on the connection target member include metal electrodes such as gold electrodes, nickel electrodes, tin electrodes, aluminum electrodes, copper electrodes, molybdenum electrodes, silver electrodes, SUS electrodes, and tungsten electrodes. When the connection target member is a flexible printed substrate, the electrodes are preferably gold electrodes, nickel electrodes, tin electrodes, silver electrodes or copper electrodes. When the connection target member is a glass substrate, the electrodes are preferably aluminum electrodes, copper electrodes, molybdenum electrodes, silver electrodes or tungsten electrodes. When the electrode is an aluminum electrode, it may be an electrode formed only of aluminum, or an electrode in which an aluminum layer is laminated on the surface of a metal oxide layer. Examples of the material of the metal oxide layer include indium oxide doped with a trivalent metal element and zinc oxide doped with a trivalent metal element. Examples of the trivalent metal element include Sn, Al and Ga.

In the connection structure according to the present invention, it is preferable that the first electrode and the second electrode are arranged in an area array or a peripheral. When the first electrode and the second electrode are arranged in an area array or peripheral, the conductive particles can be more effectively aggregated on the electrodes. The area array is a structure in which the electrodes are arranged in a grid pattern on the surface on which the electrodes of the connection target member are arranged. The peripheral is a structure in which electrodes are arranged on the outer peripheral portion of a member to be connected. In the case of a structure in which the electrodes are arranged in a comb shape, the conductive particles need to be aggregated along the direction perpendicular to the comb, whereas in the area array or the peripheral structure, the electrodes are arranged on the surface. It is necessary that the conductive particles are uniformly aggregated on the entire surface. Therefore, in the conventional method, the amount of conductive particles tends to be non-uniform, whereas in the method of the present invention, the conductive particles can be uniformly aggregated on the entire surface.

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. The present invention is not limited to the following examples.

Thermosetting component (thermosetting compound):
Thermosetting compound 1: Bisphenol A type epoxy compound, "YL980" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 180 g / eq
Thermosetting compound 2: Hydrogenated bisphenol A type epoxy compound, "YX8000" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 205 g / eq
Thermosetting compound 3: Hydrogenated bisphenol A type epoxy compound, "YX8034" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 270 g / eq
Thermosetting compound 4: Triisocyanurate type epoxy compound, "TEPIC-HP" manufactured by Nissan Chemical Industries, Ltd., epoxy equivalent 135 g / eq

Thermosetting component (thermosetting agent):
Thermosetting agent 1: Microcapsule type latent curing agent, "HXA3922HP" manufactured by Asahi Kasei Chemicals Co., Ltd.
Thermosetting agent 2: 2,4-diamino-6- [2'-methylimidazolyl- (1')] -ethyl-s-triazine isocyanuric acid adduct, "2MA-OK" manufactured by Shikoku Chemicals Corporation

flux:
Flux 1: "Benzylamine glutaric salt", melting point 108 ° C

Method for producing flux 1:
In a glass bottle, 24 g of water as a reaction solvent and 13.212 g of glutaric acid (manufactured by Wako Pure Chemical Industries, Ltd.) were put and dissolved at room temperature until uniform. Then, 10.715 g of benzylamine (manufactured by Wako Pure Chemical Industries, Ltd.) was added and stirred for about 5 minutes to obtain a mixed solution. The obtained mixture was placed in a refrigerator at 5 ° C. to 10 ° C. and left overnight. The precipitated crystals were separated by filtration, washed with water and vacuum dried to obtain flux 1.

Conductive particles:
Conductive particles 1: SnBi solder particles, melting point 139 ° C, solder particles selected from "Sn42Bi58" manufactured by Mitsui Mining & Smelting Co., Ltd., average particle diameter 2 μm

Rubber particles:
Rubber particles 1: Silicone rubber particles, "S series" manufactured by Mitsubishi Rayon, average particle diameter 50 nm

(Average particle size of solder particles and rubber particles)
The average particle size of the solder particles and the rubber particles was measured using a laser diffraction type particle size distribution measuring device (“LA-920” manufactured by HORIBA, Ltd.).

(Melting points of solder particles and flux)
The melting points of the solder particles and flux were calculated using differential scanning calorimetry (DSC). As the differential scanning calorimetry (DSC) device, "EXSTAR DSC7020" manufactured by SII was used.

(Examples 1 to 5 and Comparative Example 1)
(1) Preparation of Conductive Material (Anisotropic Conductive Paste) A conductive material (anisotropic conductive paste) was obtained by blending the components shown in Table 1 below in the blending amounts shown in Table 1 below.

(2) Preparation of First Connection Structure (A) (Area Array Substrate) As a first connection target member, on the surface of a glass epoxy substrate main body (size 20 mm × 20 mm, thickness 1.2 mm, material FR-4). , A glass epoxy substrate in which copper electrodes of 50 μm at a pitch of 100 μm are arranged in an area array and a solder resist film is formed in a region where the copper electrodes are not arranged was prepared. The step between the surface of the copper electrode and the surface of the solder resist film is 15 μm, and the solder resist film protrudes from the copper electrode.

As the second connection target member, copper electrodes are arranged on the surface of the semiconductor chip body (size 5 mm × 5 mm, thickness 0.4 mm) so as to have the same pattern as the electrodes of the first connection target member. A semiconductor chip having a passivation film (polyimide, thickness 5 μm, electrode opening diameter 200 μm) formed on the outermost surface was prepared. The number of copper electrodes is 10 x 10 per semiconductor chip, for a total of 100.

A conductive material (anisotropic conductive paste) immediately after production was applied to the upper surface of the glass epoxy substrate so as to have a thickness of 10 μm to form a conductive material (anisotropic conductive paste) layer. Next, semiconductor chips were laminated on the upper surface of the conductive material (anisotropic conductive paste) layer so that the electrodes face each other. The weight of the semiconductor chip is added to the conductive material (anisometric conductive paste) layer. From that state, the temperature of the conductive material (anisotropic conductive paste) layer was heated so as to reach the melting point of the solder 5 seconds after the start of temperature rise. Further, 15 seconds after the start of temperature rise, the conductive material (anisometric conductive paste) layer is heated to 160 ° C. to cure the conductive material (anisotropic conductive paste), and the first connection structure is formed. Body (A) was obtained. No pressurization was performed during heating.

(3) Fabrication of First Connection Structure (B) (Area Array Substrate) The conductive material (anisotropic conductive paste) immediately after production is coated so as to have a thickness of 10 μm, and the conductive material (anisometric conductivity) is coated. The first connection structure (B) was produced in the same manner as the first connection structure (A) except that the paste) layer was formed and then left as it was for 12 hours before laminating the semiconductor chips.

(4) Preparation of Second Connection Structure (A) (Peripheral Substrate) As a first connection target member, on the surface of a glass epoxy substrate main body (size 20 mm × 20 mm, thickness 1.2 mm, material FR-4), A glass epoxy substrate was prepared in which copper electrodes having a pitch of 100 μm and 50 μm were arranged (peripheral) on the outer periphery of the chip, and a solder resist film was formed in a region where the copper electrodes were not arranged. The step between the surface of the copper electrode and the surface of the solder resist film is 15 μm, and the solder resist film protrudes from the copper electrode.

As the second connection target member, copper electrodes are arranged on the surface of the semiconductor chip body (size 5 mm × 5 mm, thickness 0.4 mm) so as to have the same pattern as the electrodes of the first connection target member. A semiconductor chip having a passivation film (polyimide, thickness 5 μm, electrode opening diameter 200 μm) formed on the outermost surface was prepared. The number of copper electrodes is 10 per semiconductor chip x 4 sides, for a total of 36.

A conductive material (anisotropic conductive paste) immediately after production was applied to the peripheral portion on the upper surface of the glass epoxy substrate so as to have a thickness of 10 μm to form a conductive material (anisotropic conductive paste) layer. Next, semiconductor chips were laminated on the upper surface of the conductive material (anisotropic conductive paste) layer so that the electrodes face each other. The weight of the semiconductor chip is added to the conductive material (anisometric conductive paste) layer. From that state, the temperature of the conductive material (anisotropic conductive paste) layer was heated so as to reach the melting point of the solder 5 seconds after the start of temperature rise. Further, 15 seconds after the start of temperature rise, the conductive material (anisometric conductive paste) layer is heated to 160 ° C. to cure the conductive material (anisotropic conductive paste), and the second connection structure is formed. Body (A) was obtained. No pressurization was performed during heating.

(5) Preparation of Second Connection Structure (B) (Peripheral Substrate) The conductive material (anisotropic conductive paste) immediately after production is coated so as to have a thickness of 10 μm, and the conductive material (anisotropic conductive paste) is applied. The second connection structure (B) was produced in the same manner as the second connection structure (A) except that the layer was left as it was for 12 hours before the semiconductor chips were laminated.

(Evaluation)
(1) Viscosity of conductive material at 25 ° C (η25)
A conductive material (anisotropic conductive paste) immediately after production was prepared. The viscosity (η25) of the conductive material at 25 ° C. was measured using an E-type viscometer (“TVE22L” manufactured by Toki Sangyo Co., Ltd.) under the conditions of 25 ° C. and 5 rpm.

(2) Viscosity of conductive material at 60 ° C (η60)
The viscosity of the conductive material (anisotropic conductive paste) immediately after production is measured by using STRESSTECH (manufactured by REOLOGICA) with strain control of 1 rad, frequency of 1 Hz, heating rate of 20 ° C./min, and measurement temperature range of 25 ° C. to 200 ° C. Measured under conditions. In this measurement, the viscosity at 60 ° C. was read and used as the viscosity of the conductive material (anisometric conductive paste) at 60 ° C.

(3) Placement accuracy of solder on electrodes In the obtained first and second connection structures (A) (20 pieces each), the first electrode, the connection portion, and the second electrode are laminated in the stacking direction. When looking at the facing portions of the first electrode and the second electrode, the solder portion in the connecting portion is arranged in 100% of the area of the facing portions of the first electrode and the second electrode. The ratio (A) of the area to be soldered was evaluated. The area ratio (A) was calculated by averaging 20 values. From the area ratio (A), the accuracy of solder placement on the electrodes was determined according to the following criteria.

[Criteria for determining the accuracy of solder placement on electrodes]
○○: Ratio (A) is 70% or more ○: Ratio (A) is 60% or more and less than 70% Δ: Ratio (A) is 50% or more and less than 60% ×: Ratio (A) is less than 50%

(4) Conductivity reliability between the upper and lower electrodes In the obtained first and second connection structures (A) (20 pieces each), the connection resistance between the upper and lower electrodes was measured by the 4-terminal method. The average value of the connection resistance was calculated. From the relationship of voltage = current x resistance, the connection resistance can be obtained by measuring the voltage when a constant current is passed. The continuity reliability was judged according to the following criteria.

[Criteria for conduction reliability]
○ ○: Average value of connection resistance is 8.0Ω or less ○: Average value of connection resistance is more than 8.0Ω and 10.0Ω or less △: Mean value of connection resistance is more than 10.0Ω and 15.0Ω or less ×: Connection Average resistance exceeds 15.0Ω

(5) Insulation reliability between adjacent electrodes In the obtained first and second connection structures (A) (20 pieces each), after being left in an atmosphere at a temperature of 85 ° C. and a humidity of 85% for 100 hours, 5V was applied between the adjacent electrodes, and the resistance value was measured at 25 points. The average value of the connection resistance was obtained by averaging 20 values. The insulation reliability was judged according to the following criteria.

[Criteria for insulation reliability]
○○: Connection average value of the resistance is 10 ⁷ Omega more ○: Connection average of less than 10 ⁶ Omega least 10 ⁷ Omega resistor △: average value of connection resistance 10 ⁵ Omega least 10 less than ⁶ Omega ×: the connection resistance the average value is less than 10 ⁵ Ω

(6) Maintainability of placement accuracy In the obtained first and second connection structures (B) (20 pieces each), the first electrode in the stacking direction of the first electrode, the connection portion, and the second electrode. When looking at the parts facing each other with the second electrode, the area where the solder part in the connecting part is arranged in 100% of the area of the parts facing each other between the first electrode and the second electrode. The ratio (B) of was evaluated. The area ratio (B) was calculated by averaging 20 values. The placement accuracy maintainability was evaluated from the area ratio (B). The placement accuracy maintainability was judged according to the following criteria.

[Criteria for maintaining placement accuracy]
○○: Ratio (B) is 70% or more ○: Ratio (B) is 60% or more and less than 70% Δ: Ratio (B) is 50% or more and less than 60% ×: Ratio (B) is less than 50%

(7) Positional deviation when the members to be connected are arranged When the first and second connection structures (A) (20 pieces each) are manufactured, the second member to be connected (semiconductor chip) is made of a conductive material. It was confirmed whether or not it was accurately placed in a predetermined place on the surface. The misalignment of the members to be connected when arranged was determined according to the following criteria.

[Criteria for determining misalignment when arranging members to be connected]
○○: The number of connection structures in which the second connection target member (semiconductor chip) is accurately arranged at a predetermined position on the surface of the conductive material is 100%.
◯: The number of connection structures in which the second connection target member (semiconductor chip) is accurately arranged at a predetermined position on the surface of the conductive material is 90% or more and less than 100% Δ: The second connection target member ( The number of connection structures in which the semiconductor chip) is accurately arranged at a predetermined position on the surface of the conductive material is 50% or more and less than 90% ×: The second connection target member (semiconductor chip) is on the surface of the conductive material. Less than 50% of connected structures are accurately placed in place in

(8) Contact angle of conductive material with respect to non-alkali glass substrate Using the obtained conductive material, screen mesh BS500-16CAL is placed on a non-alkali glass substrate (“EAGLEXG 50 × 0.7-25” manufactured by Corning Inc.). Then, screen printing was performed under the following conditions so that the width was 100 μm, the length was 200 μm, and the thickness was 10 μm. The above conditions are a temperature of 25 ° C., a clearance of 1.5 mm, a squeegee angle of 70 °, a squeegee printing pressure of 0.15 MPa, and a squeegee speed of 60 mm / s. The contact angle of the conductive material with respect to the non-alkali glass substrate was measured using a contact angle measuring device (“DMo-601” manufactured by KYOUWA). The contact angle of the conductive material with respect to the non-alkali glass substrate was calculated by averaging the contact angles of 10 points of the conductive material screen-printed.

The results are shown in Table 1 below.

The same tendency was observed when a flexible printed circuit board, a resin film, a flexible flat cable, and a rigid flexible substrate were used.

1,1X ... Connection structure 2 ... First connection target member 2a ... First electrode 3 ... Second connection target member 3a ... Second electrode 4,4X ... Connection part 4A, 4XA ... Solder part 4B, 4XB … Hardened part 11… Conductive material 11A… Solder particles (conductive particles)
11B ... Thermosetting component 21 ... Conductive particles 31 ... Conductive particles 32 ... Base particles 33 ... Conductive part 33A ... Second conductive part 33B ... First conductive part (solder part)
41 ... Conductive particles 42 ... Conductive part

Claims (9)

A conductive material containing a thermosetting component and a plurality of conductive particles.
A screen mesh BS500-16CAL is placed on a non-alkali glass substrate, and using the conductive material, the temperature is 25 ° C., the clearance is 1.5 mm, and the squeegee angle is 70 ° so that the width is 100 μm, the length is 200 μm, and the thickness is 10 μm. , A conductive material in which the contact angle of the conductive material with respect to the non-alkali glass substrate is 20 ° or more when screen printing is performed under the conditions of a squeegee printing pressure of 0.15 MPa and a squeegee speed of 60 mm / s. The conductive material according to claim 1, which comprises a plurality of rubber particles. The thermosetting component contains an epoxy compound and contains
The conductive material according to claim 1 or 2, wherein the epoxy equivalent of the epoxy compound is 100 g / eq or more and 1000 g / eq or less. The conductive material according to any one of claims 1 to 3, wherein the conductive particles are solder particles. The conductive material contains a coupling agent and contains
The conductive material according to any one of claims 1 to 4, wherein the coupling agent is contained in 100% by weight or less of the conductive material in an amount of 3% by weight or less. The conductive material according to any one of claims 1 to 5, wherein the viscosity of the conductive material at 25 ° C. is 1 Pa · s or more and 200 Pa · s or less. The conductive material according to any one of claims 1 to 6, wherein the viscosity of the conductive material at 60 ° C. is 0.01 Pa · s or more and 50 Pa · s or less. The conductive material according to any one of claims 1 to 7, which is a conductive paste. A first connection target member having a first electrode on its surface,
A second connection target member having a second electrode on the surface,
A connecting portion connecting the first connection target member and the second connection target member is provided.
The material of the connecting portion is the conductive material according to any one of claims 1 to 8.
A connection structure in which the first electrode and the second electrode are electrically connected by the conductive particles.

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