JPWO2020009238A1 - Conductive particles with insulating particles, conductive materials and connecting structures - Google Patents

Abstract

Provided are conductive particles with insulating particles capable of effectively increasing conduction reliability and further effectively increasing insulation reliability when the electrodes are electrically connected. The conductive particles with insulating particles according to the present invention include conductive particles having a conductive portion at least on the surface and a plurality of insulating particles arranged on the surface of the conductive particles, and are the insulating particles. The particle size is 500 nm or more and 1500 nm or less, and the storage elastic coefficient of the insulating particles at 60 ° C. is 100 MPa or more and 1000 MPa or less.

Description

The present invention relates to conductive particles with insulating particles in which insulating particles are arranged on the surface of the conductive particles. The present invention also relates to a conductive material and a connecting structure using the conductive particles with insulating particles.

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 resin. Further, as the conductive particles, conductive particles having an insulating treatment on the surface of the conductive layer may be used.

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 the like. Examples thereof include a connection between a semiconductor 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)).

Further, as the conductive particles, conductive particles with insulating particles in which insulating particles are arranged on the surface of the conductive particles may be used. Further, coated conductive particles in which an insulating layer is arranged on the surface of the conductive layer may be used.

As an example of the conductive particles with insulating particles, Patent Document 1 below includes insulating particles having a conductive layer on the surface and insulating particles adhering to the surface of the conductive particles. Conductive particles with particles are disclosed. In the conductive particles with insulating particles, the insulating particles have a hydroxyl group directly bonded to a phosphorus atom or a hydroxyl group directly bonded to a silicon atom on the surface.

In Patent Document 2 below, conductive particles having a conductive portion at least on the surface, and a main body of conductive particles with insulating particles having a plurality of insulating particles arranged on the surface of the conductive particles, and the above-mentioned insulation. Conductive particles with insulating particles Conductive particles with insulating particles include a coating covering the surface of the main body of the conductive particles with insulating particles. In the conductive particles with insulating particles, the coating film has a first coating portion covering the conductive particles and a second coating portion covering the surface of the insulating particles. In the conductive particles with insulating particles, the thickness of the first coating portion is ½ or less of the average particle size of the insulating particles.

WO2011 / 030715A1 Japanese Unexamined Patent Publication No. 2013-175453

When making a conductive connection using a conductive material containing conductive particles, the plurality of electrodes on the upper side and the plurality of electrodes on the lower side are electrically connected to perform the conductive connection. 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 the adjacent lateral electrodes are not electrically connected.

In conventional conductive particles with insulating particles, although the conductive surface is covered with insulating particles, laterally adjacent electrodes that must not be connected after the conductive connection between the upper and lower electrodes to be connected. It can be difficult to suppress the electrical connections between them. In particular, when conductive particles having a relatively large particle size are used, it may be difficult to sufficiently improve the insulation reliability between adjacent lateral electrodes in the conductively connected connection structure.

Further, in the conventional conductive particles with insulating particles, the insulating particles may be arranged on the surface of the conductive particles by using a coating film such as an organic compound or an inorganic oxide. When the insulating particles are arranged on the surface of the conductive particles using the above coating, the insulating particles may not easily come off from the surface of the conductive particles at the time of conductive connection, and between the upper and lower electrodes to be connected. It may be difficult to sufficiently improve the continuity reliability of the particles. With conventional conductive particles with insulating particles, it is difficult to effectively improve the conduction reliability between the upper and lower electrodes to be connected and the insulation reliability between the laterally adjacent electrodes that should not be connected. There is.

An object of the present invention is to provide conductive particles with insulating particles that can effectively improve conduction reliability and further improve insulation reliability when the electrodes are electrically connected. To provide. Another object of the present invention is to provide a conductive material and a connecting structure using the conductive particles with insulating particles.

According to a broad aspect of the present invention, conductive particles having at least a conductive portion on the surface and a plurality of insulating particles arranged on the surface of the conductive particles are provided, and the particle size of the insulating particles is determined. Provided are conductive particles with insulating particles having a storage elastic coefficient of 500 nm or more and 1500 nm or less and the insulating particles at 60 ° C. of 100 MPa or more and 1000 MPa or less.

In a specific aspect of the conductive particles with insulating particles according to the present invention, the conductive particles have protrusions on the outer surface of the conductive portion.

In a specific aspect of the conductive particles with insulating particles according to the present invention, the ratio of the particle size of the conductive particles to the particle size of the insulating particles is 3 or more and 100 or less.

In a specific aspect of the conductive particles with insulating particles according to the present invention, the swelling ratio of the insulating particles is 1 or more and 2.5 or less.

In a specific aspect of the conductive particles with insulating particles according to the present invention, the conductive particles are arranged so that 10% or more of the total number of the insulating particles does not come into contact with the other insulating particles. Arranged on the surface.

In a specific aspect of the conductive particles with insulating particles according to the present invention, the particle size of the conductive particles is 1 μm or more and 50 μm or less.

According to a broad aspect of the present invention, there is provided a conductive material including the above-mentioned conductive particles with insulating particles and a binder resin.

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. It is provided with a connecting portion connecting the second connection target member, and the material of the connecting portion is the above-mentioned conductive particles with insulating particles, or the conductive particles with insulating particles and a binder resin. Provided is a connecting structure comprising the above, wherein the first electrode and the second electrode are electrically connected by the conductive portion of the conductive particles with insulating particles. ..

The conductive particles with insulating particles according to the present invention include conductive particles having a conductive portion at least on the surface, and a plurality of insulating particles arranged on the surface of the conductive particles. In the conductive particles with insulating particles according to the present invention, the particle size of the insulating particles is 500 nm or more and 1500 nm or less. In the conductive particles with insulating particles according to the present invention, the storage elastic modulus of the insulating particles at 60 ° C. is 100 MPa or more and 1000 MPa or less. Since the conductive particles with insulating particles according to the present invention have the above-mentioned configuration, the conduction reliability can be effectively improved when the electrodes are electrically connected, and the insulation reliability can be further improved. Sex can be effectively enhanced.

FIG. 1 is a cross-sectional view showing conductive particles with insulating particles according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view showing conductive particles with insulating particles according to a second embodiment of the present invention. FIG. 3 is a cross-sectional view showing conductive particles with insulating particles according to a third embodiment of the present invention. FIG. 4 is a cross-sectional view schematically showing a connection structure using conductive particles with insulating particles according to the first embodiment of the present invention.

The details of the present invention will be described below.

(Conductive particles with insulating particles)
The conductive particles with insulating particles according to the present invention include conductive particles having a conductive portion at least on the surface, and a plurality of insulating particles arranged on the surface of the conductive particles. In the conductive particles with insulating particles according to the present invention, the particle size of the insulating particles is 500 nm or more and 1500 nm or less. In the conductive particles with insulating particles according to the present invention, the storage elastic modulus of the insulating particles at 60 ° C. is 100 MPa or more and 1000 MPa or less.

Since the conductive particles with insulating particles according to the present invention have the above-mentioned configuration, the conduction reliability can be effectively improved when the electrodes are electrically connected, and the insulation reliability can be further improved. Sex can be effectively enhanced.

In conventional conductive particles with insulating particles, although the conductive surface is covered with insulating particles, laterally adjacent electrodes that must not be connected after the conductive connection between the upper and lower electrodes to be connected. It can be difficult to suppress the electrical connections between them. In particular, when conductive particles having a relatively large particle size are used, there is a problem that the insulation reliability between adjacent lateral electrodes in the conductively connected connection structure cannot be sufficiently improved.

As a result of diligent studies to solve the above problems, the present inventors have found that the above problems can be solved by using specific insulating particles. In the present invention, since the specific insulating particles are used, the insulation reliability between the adjacent lateral electrodes in the conductively connected connection structure can be effectively enhanced.

Further, in the present invention, since the insulating particles can be effectively arranged on the surface of the conductive particles by using the specific insulating particles, it is necessary to use a coating such as an organic compound or an inorganic oxide. do not have. As a result, the insulating particles are likely to come off from the surface of the conductive particles at the time of conductive connection, and the conduction reliability between the upper and lower electrodes to be connected can be effectively improved. In the present invention, it is possible to effectively improve the conduction reliability between the upper and lower electrodes to be connected and the insulation reliability between the horizontally adjacent electrodes that should not be connected.

In the present invention, the use of specific insulating particles greatly contributes to obtaining the above-mentioned effects.

From the viewpoint of further effectively enhancing the conduction reliability and insulation reliability between the electrodes, the coefficient of variation (CV value) of the particle size of the conductive particles with insulating particles is preferably 10% or less, more preferably 10% or less. It is 5% or less.

The coefficient of variation (CV value) can be measured as follows.

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

The shape of the conductive particles with insulating particles is not particularly limited. The shape of the conductive particles with insulating particles may be spherical, non-spherical, flat or the like.

The conductive particles with insulating particles are dispersed in the binder resin and are suitably used for obtaining a conductive material.

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

FIG. 1 is a cross-sectional view showing conductive particles with insulating particles according to the first embodiment of the present invention.

The conductive particles 1 with insulating particles shown in FIG. 1 include the conductive particles 2 and a plurality of insulating particles 3 arranged on the surface of the conductive particles 2. The insulating particles 3 are formed of an insulating material.

The conductive particles 2 have a base particle 11 and a conductive portion 12 arranged on the surface of the base particle 11. In the conductive particles 1 with insulating particles, the conductive portion 12 is a conductive layer. The conductive portion 12 covers the surface of the base particle 11. The conductive particles 2 are coated particles in which the surface of the base particle 11 is coated with the conductive portion 12. The conductive particles 2 have a conductive portion 12 on the surface. In the conductive particles, the conductive portion may cover the entire surface of the base material particles, or the conductive portion may cover a part of the surface of the base material particles. In the conductive particles with insulating particles, it is preferable that the insulating particles are arranged on the surface of the conductive portion.

FIG. 2 is a cross-sectional view showing conductive particles with insulating particles according to a second embodiment of the present invention.

The conductive particles 21 with insulating particles shown in FIG. 2 include the conductive particles 22 and a plurality of insulating particles 3 arranged on the surface of the conductive particles 22.

The conductive particles 22 have a base particle 11 and a conductive portion 31 arranged on the surface of the base particle 11. In the conductive particles 21 with insulating particles, the conductive portion 31 is a conductive layer. The conductive particles 22 have a plurality of core substances 32 on the surface of the base particles 11. The conductive portion 31 covers the base material particles 11 and the core material 32. Since the core material 32 is covered with the conductive portion 31, the conductive particles 22 have a plurality of protrusions 33 on the surface. In the conductive particles 22, the surface of the conductive portion 31 is raised by the core substance 32, and a plurality of protrusions 33 are formed. In the conductive particles, the conductive portion may cover the entire surface of the base material particles, or the conductive portion may cover a part of the surface of the base material particles. In the conductive particles with insulating particles, it is preferable that the insulating particles are arranged on the surface of the conductive portion.

FIG. 3 is a cross-sectional view showing conductive particles with insulating particles according to a third embodiment of the present invention.

The conductive particles 41 with insulating particles shown in FIG. 3 include conductive particles 42 and a plurality of insulating particles 3 arranged on the surface of the conductive particles 42.

The conductive particles 42 have a base particle 11 and a conductive portion 51 arranged on the surface of the base particle 11. In the conductive particles 41 with insulating particles, the conductive portion 51 is a conductive layer. The conductive particles 42 do not have a core substance like the conductive particles 22. The conductive portion 51 has a first portion and a second portion that is thicker than the first portion. The conductive particles 42 have a plurality of protrusions 52 on the surface. The portion excluding the plurality of protrusions 52 is the first portion of the conductive portion 51. The plurality of protrusions 52 are the second portion where the conductive portion 51 is thick. In the conductive particles, the conductive portion may cover the entire surface of the base material particles, or the conductive portion may cover a part of the surface of the base material particles. In the conductive particles with insulating particles, it is preferable that the insulating particles are arranged on the surface of the conductive portion.

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

Conductive particles:
The conductive particles preferably have a base material particles and a conductive portion arranged on the surface of the base material particles. The conductive portion may have a single-layer structure or a multi-layer structure having two or more layers.

The particle size of the conductive particles is preferably 1 μm or more, more preferably 10 μm or more, preferably 50 μm or less, and more preferably 40 μm or less. When the particle size 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 contact area between the conductive particles and the electrodes becomes sufficiently large when the electrodes are connected using the conductive particles. Moreover, it becomes difficult to form agglomerated conductive particles when forming the conductive portion. In addition, the distance between the electrodes connected via the conductive particles does not become too large, and the conductive portion does not easily peel off from the surface of the substrate particles.

The particle size of the conductive particles is preferably an average particle size, and more preferably a number average particle size. The particle size of the conductive particles can be determined by, for example, observing 50 arbitrary conductive particles with an electron microscope or an optical microscope, calculating the average value of the particle size of each conductive particle, or measuring the particle size distribution by laser diffraction. Is required by doing. When measuring the particle size of the conductive particles by a method of observing 50 arbitrary conductive particles with an electron microscope or an optical microscope, for example, it can be measured 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 each conductive particle is observed. The equivalent circle diameter of each conductive particle is measured as the particle diameter, and they are arithmetically averaged to obtain the particle diameter of the conductive particle. Instead of the embedded resin for conducting conductive particle inspection, an embedded resin for conducting conductive particle inspection with insulating particles may be prepared.

The coefficient of variation (CV value) of the particle size of the conductive particles is preferably 10% or less, more preferably 5% or less. When the coefficient of variation of the particle size of the conductive particles is not more than the above upper limit, the conduction reliability and the insulation reliability between the electrodes can be further effectively improved.

The coefficient of variation (CV value) can be measured as follows.

CV value (%) = (ρ / Dn) × 100
ρ: Standard deviation of particle size of conductive particles Dn: Average 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, non-spherical, flat or the like.

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 base particle other than the inorganic particle. 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.

Various organic substances 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; polycarbonate, polyamide, and the like. 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, polyethylene terephthalate, polysulfone, polyphenylene oxide, polyacetal, Examples thereof include polyimides, polyamideimides, polyether ether ketones, polyether sulfones, divinylbenzene polymers, and divinylbenzene-based copolymers. Examples of the divinylbenzene-based copolymer and the like include a divinylbenzene-styrene copolymer and a divinylbenzene- (meth) acrylic acid ester copolymer. Since the hardness of the resin particles can be easily controlled within a suitable range, the material of the resin particles must be a polymer obtained by polymerizing one or more polymerizable monomers having an ethylenically unsaturated group. Is preferable.

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; and carboxyl group-containing monomers such as (meth) acrylic acid, maleic acid, and maleic anhydride; Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, Alkyl (meth) acrylate compounds such as cyclohexyl (meth) acrylate and isobornyl (meth) acrylate; 2-hydroxyethyl (meth) acrylate, glycerol (meth) acrylate, polyoxyethylene (meth) acrylate, and glycidyl (meth) acrylate. Oxylate atom-containing (meth) acrylate compounds such as (meth) acrylonitrile and the like; nitrile-containing monomers such as (meth) acrylonitrile; vinyl ether compounds such as methyl vinyl ether, ethyl vinyl ether, and propyl vinyl ether; vinyl acetate, vinyl butyrate, vinyl laurate, and stearic acid. Acid vinyl ester compounds such as vinyl; unsaturated hydrocarbons such as ethylene, propylene, isoprene, and butadiene; trifluoromethyl (meth) acrylate, pentafluoroethyl (meth) acrylate, vinyl chloride, vinyl fluoride, chlorostyrene, etc. Halogen-containing monomers and the like 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, and 1,4-butanediol di (meth) acrylates; triallyl (iso) cyanurate, triallyl trimellitate, divinylbenzene. , Dialyl phthalate, diallyl acrylamide, diallyl ether, and silane-containing monomers such as γ- (meth) acryloxypropyltrimethoxysilane, trimethoxysilylstyrene, and vinyltrimethoxysilane.

The term "(meth) acrylate" refers to acrylate and methacrylate. The term "(meth) acrylic" refers to acrylic and methacrylic. The term "(meth) acryloyl" refers to acryloyl and methacryloyl.

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 for forming the base material particles include silica, alumina, barium titanate, zirconia, and carbon black. .. The inorganic substance is preferably 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 effectively reducing 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 for the organic core include the above-mentioned material for resin particles.

Examples of the material of the inorganic shell include the above-mentioned inorganic substances as the material of 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 silver, copper, nickel, silicon, gold, and titanium.

The particle size of the base particles is preferably 0.6 μm or more, more preferably 0.8 μm or more, preferably 49.8 μm or less, and more preferably 49.6 μm or less. When the particle size of the base material particles is not less than the above lower limit and not more than the above upper limit, small conductive particles can be obtained even if the distance between the electrodes is small and the thickness of the conductive portion (conductive layer or the like) is increased. Be done. 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.

The particle size of the base particles is particularly preferably 0.9 μm or more and 49.9 μm or less. When the particle size of the base material particles is within the range of 0.9 μm or more and 49.9 μm or less, it becomes difficult to agglomerate when forming a conductive portion on the surface of the base material particles, and agglomerated conductive particles are formed. It becomes difficult.

The particle size of the base particle indicates a number average particle size. The particle size of the base particle is determined by using a particle size distribution measuring device or the like. As for the particle size of the base particle, 50 arbitrary base particles are observed with an electron microscope or an optical microscope, the average value of the particle size of each base particle is calculated, and the laser diffraction type particle size distribution measurement is performed. It is preferable to obtain the results. When measuring the particle size of the base particle by a method of observing 50 arbitrary base particles with an electron microscope or an optical microscope in the conductive particles, for example, it can be measured 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. do. The circle-equivalent diameter of the base material particles in each conductive particle is measured as the particle size, and they are arithmetically averaged to obtain the particle size of the base material particles. Instead of the embedded resin for conducting conductive particle inspection, an embedded resin for conducting conductive particle inspection with insulating particles may be prepared.

Conductive part:
In the present invention, the conductive particles have a conductive portion at least on the surface. The conductive portion preferably contains a metal. The metal constituting the 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. From the viewpoint of further lowering the connection resistance between the electrodes, an alloy containing tin, nickel, palladium, copper or gold is preferable, and nickel or palladium is more preferable.

Further, from the viewpoint of effectively enhancing the conduction reliability, it is preferable that the conductive portion and the outer surface portion of the conductive portion contain nickel. The content of nickel in 100% by weight of the conductive portion containing nickel is preferably 10% by weight or more, more preferably 50% by weight or more, still more preferably 60% by weight or more, still more preferably 70% by weight or more, particularly preferably. Is 90% by weight or more. The content of nickel in 100% by weight of the conductive portion containing nickel may be 97% by weight or more, 97.5% by weight or more, or 98% by weight or more.

In addition, hydroxyl groups are often present on the surface of the conductive portion due to oxidation. Generally, a hydroxyl group is present on the surface of a conductive portion formed of nickel due to oxidation. Insulating particles can be arranged on the surface of the conductive portion having such a hydroxyl group (the surface of the conductive particles) via a chemical bond.

The conductive portion may be formed by one layer. The conductive portion may be formed of a plurality of layers. That is, the conductive portion may have a laminated structure of two or more layers. When the conductive portion is formed of a plurality of layers, the metal constituting the outermost layer is preferably gold, nickel, palladium, copper or an alloy containing tin and silver, and is preferably gold. More preferred. When the metal constituting the outermost layer is these preferred metals, the connection resistance between the electrodes becomes even lower. Further, when the metal constituting the outermost layer is gold, the corrosion resistance is further enhanced.

The method of forming the conductive portion on the surface of the base particle is not particularly limited. Examples of the method for forming the conductive portion include a method by electroless plating, a method by electroplating, a method by physical collision, a method by mechanochemical reaction, a method by physical vapor deposition or physical adsorption, and a metal powder or Examples thereof include a method of coating the surface of the substrate particles with a paste containing a metal powder and a binder. The method for forming the 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 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 thickness of the 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, still more preferably 0.3 μm or less. When the thickness of the conductive portion is not less than the above lower limit and not more than the above upper limit, sufficient conductivity can be obtained, and the conductive particles do not become too hard, and the conductive particles are sufficiently formed at the time of connection between the electrodes. It can be transformed.

When the conductive portion is formed of a plurality of layers, the thickness of the conductive portion of the outermost layer is preferably 0.001 μm or more, more preferably 0.01 μm or more, preferably 0.5 μm or less, more preferably. Is 0.1 μm or less. When the thickness of the conductive portion of the outermost layer is equal to or higher than the lower limit and lower than the upper limit, the conductive portion of the outermost layer becomes uniform, the corrosion resistance becomes sufficiently high, and the connection resistance between the electrodes is sufficiently low. can do.

The thickness of the conductive portion can be measured by observing the cross section of the conductive particles using, for example, a transmission electron microscope (TEM).

Core material:
The conductive particles preferably have a plurality of protrusions on the outer surface of the conductive portion. An oxide film is often formed on the surface of the electrode connected by the conductive particles with insulating particles. When conductive particles with insulating particles having protrusions on the surface of the conductive portion are used, the above-mentioned oxide film is effectively formed by the protrusions by arranging the conductive particles with insulating particles between the electrodes and crimping them. Can be eliminated. Therefore, the electrodes and the conductive portion come into contact with each other more reliably, and the connection resistance between the electrodes becomes even lower. Further, when the electrodes are connected, the protrusions of the conductive particles can effectively eliminate the insulating particles between the conductive particles and the electrodes. Therefore, the continuity reliability between the electrodes is further increased.

As a method of forming the above-mentioned protrusions, a method of forming a conductive portion by electroless plating after adhering a core substance to the surface of the base material particles, and a method of forming a conductive portion by electroless plating on the surface of the base material particles. After that, a method of adhering a core substance and further forming a conductive portion by electroless plating can be mentioned. As another method for forming the protrusions, after forming the first conductive portion on the surface of the base particle, the core substance is arranged on the first conductive portion, and then the second conductive portion is formed. And a method of adding a core substance in the middle of forming a conductive portion (first conductive portion, second conductive portion, etc.) on the surface of the base particle. Further, in order to form protrusions, a conductive portion is formed on the base material particles by electroless plating without using the above-mentioned core substance, and then plating is deposited in a protrusion shape on the surface of the conductive portion, and further electroless plating is performed. A method of forming a conductive portion by means of a plating method or the like may be used.

As a method of adhering the core substance to the surface of the base particle, for example, the core substance is added to the dispersion liquid of the base particle, and the core substance is accumulated on the surface of the base particle by van der Waals force. Examples thereof include a method of adhering the core substance to a container containing the base material particles, and a method of adding the core substance to the surface of the base material particles by a mechanical action such as rotation of the container. From the viewpoint of controlling the amount of the core substance to be adhered, the method of adhering the core substance to the surface of the base material particles is a method of accumulating and adhering the core substance to the surface of the base material particles in the dispersion liquid. preferable.

Examples of the substance constituting the core substance include a conductive substance and a non-conductive substance. Examples of the conductive substance include metals, metal oxides, conductive non-metals such as graphite, and conductive polymers. Examples of the conductive polymer include polyacetylene and the like. Examples of the non-conductive substance include silica, alumina and zirconia. From the viewpoint of further enhancing the conduction reliability between the electrodes, it is preferable that the core material is a metal.

The metal is not particularly limited. Examples of the metal include metals such as gold, silver, copper, platinum, zinc, iron, lead, tin, aluminum, cobalt, indium, nickel, chromium, titanium, antimony, bismuth, germanium and cadmium, and tin-lead. Examples thereof include alloys composed of two or more kinds of metals such as alloys, tin-copper alloys, tin-silver alloys, tin-lead-silver alloys and tungsten carbide. From the viewpoint of further enhancing the conduction reliability between the electrodes, the metal is preferably nickel, copper, silver or gold. The metal may be the same as or different from the metal constituting the conductive portion (conductive layer).

The shape of the core substance is not particularly limited. The shape of the core material is preferably lumpy. Examples of the core material include a particulate mass, an agglomerated mass in which a plurality of fine particles are aggregated, an amorphous mass, and the like.

The particle size (average particle size) of the core substance is preferably 0.001 μm or more, more preferably 0.05 μm or more, preferably 0.9 μm or less, and more preferably 0.2 μm or less. When the particle size of the core substance is not less than the above lower limit and not more than the upper limit, the connection resistance between the electrodes can be effectively reduced.

The particle size of the core material is preferably an average particle size, and more preferably a number average particle size. For the particle size of the core material, for example, observe 50 arbitrary core materials with an electron microscope or an optical microscope, calculate the average value of the particle size of each core material, or perform laser diffraction type particle size distribution measurement. Demanded by. When measuring the particle size of the core substance by a method of observing 50 arbitrary core substances with an electron microscope or an optical microscope in the conductive particles, the particle size of the core substance can be measured as follows, for example.

Conductive particles are added to "Technobit 4000" manufactured by Kulzer so as to have a content of 30% by weight and dispersed to prepare an embedded resin for conducting conductive particle inspection. 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 200,000 times, 50 conductive particles are randomly selected, and the core substance of the conductive particles is observed. The circle-equivalent diameter of the core material in each conductive particle is measured as the particle diameter, and they are arithmetically averaged to obtain the particle diameter of the core material. Instead of the embedded resin for conducting conductive particle inspection, an embedded resin for conducting conductive particle inspection with insulating particles may be prepared.

Insulating particles:
The conductive particles with insulating particles according to the present invention include a plurality of insulating particles arranged on the surface of the conductive particles. In this case, if the conductive particles with insulating particles are used for the connection between the electrodes, a short circuit between adjacent electrodes can be prevented. Specifically, when a plurality of conductive particles with insulating particles come into contact with each other, the insulating particles are present between the plurality of electrodes, so that short-circuiting between the electrodes adjacent to each other in the lateral direction rather than between the upper and lower electrodes is prevented. can. By pressurizing the conductive particles with insulating particles with the two electrodes at the time of connection between the electrodes, the insulating particles between the conductive portion of the conductive particles and the electrodes can be easily eliminated. Further, in the case of conductive particles having a plurality of protrusions on the outer surface of the conductive portion, the insulating particles between the conductive portion and the electrode of the conductive portion can be more easily eliminated.

In the conductive particles with insulating particles according to the present invention, the particle size of the insulating particles is 500 nm or more and 1500 nm or less. In the conductive particles with insulating particles according to the present invention, the insulating particles are relatively large. Therefore, even when conductive particles having a relatively large particle size are used, the insulation reliability between the adjacent lateral electrodes in the conductively connected connection structure can be further effectively enhanced. ..

The particle size of the insulating particles can be appropriately selected depending on the particle size of the conductive particles with insulating particles, the intended use of the conductive particles with insulating particles, and the like. The particle size of the insulating particles preferably exceeds 540 nm, more preferably 550 nm or more, further preferably 700 nm or more, particularly preferably 800 nm or more, preferably 1500 nm or less, more preferably 1200 nm or less, still more preferably. It is less than 1000 nm, more preferably 900 nm or less, and even more preferably 850 nm or less. When the particle size of the insulating particles satisfies the lower limit, when the conductive particles with insulating particles are dispersed in the binder resin, the conductive portions of the plurality of conductive particles with insulating particles come into contact with each other. It becomes difficult to do. When the particle size of the insulating particles satisfies the upper limit, it is not necessary to increase the pressure too high in order to eliminate the insulating particles between the electrodes and the conductive particles when connecting the electrodes. There is no need to heat to high temperature. When the particle size of the insulating particles satisfies the lower limit and the upper limit, the insulation reliability can be further effectively improved when the electrodes are electrically connected.

The particle size of the insulating particles is preferably an average particle size, and preferably a number average particle size. The particle size of the insulating particles can be determined by using a particle size distribution measuring device or the like. The particle size of the insulating particles is preferably determined by observing 50 arbitrary insulating particles with an electron microscope or an optical microscope, calculating an average value, or performing a laser diffraction type particle size distribution measurement. In the conductive particles with insulating particles, when measuring the particle size of the insulating particles by a method of observing 50 arbitrary insulating particles with an electron microscope or an optical microscope, for example, as follows. Can be measured.

Conductive particles with insulating particles are added to "Technobit 4000" manufactured by Kulzer so as to have a content of 30% by weight and dispersed to prepare an embedded resin for conducting conductive particle inspection. Using an ion milling device (“IM4000” manufactured by Hitachi High-Technologies Corporation) so as to pass near the center of the dispersed conductive particles with insulating particles in the embedded resin for inspection, the cross section of the conductive particles with insulating particles is formed. break the ice. Then, using an electric field radiation scanning electron microscope (FE-SEM), the image magnification was set to 50,000 times, 50 conductive particles with insulating particles were randomly selected, and each conductive particle with insulating particles was selected. Observe the insulating particles of the sex particles. The circle-equivalent diameter of the insulating particles in each conductive particle with insulating particles is measured as the particle diameter, and they are arithmetically averaged to obtain the particle diameter of the insulating particles.

The ratio of the particle size of the conductive particles to the particle size of the insulating particles (particle size of the conductive particles / particle size of the insulating particles) is preferably 3 or more, more preferably 6 or more, still more preferably 16. It is more than that, preferably 100 or less, more preferably 55 or less, still more preferably 30 or less. When the above ratio (particle size of conductive particles / particle size of insulating particles) is equal to or more than the above lower limit and less than or equal to the above upper limit, the insulation reliability and conduction reliability are further improved when the electrodes are electrically connected. It can be enhanced more effectively.

In the conductive particles with insulating particles according to the present invention, the storage elastic modulus of the insulating particles at 60 ° C. is 100 MPa or more and 1000 MPa or less. The storage elastic modulus of the insulating particles at 60 ° C. is preferably 300 MPa or more, more preferably 500 MPa or more, preferably 950 MPa or less, and more preferably 900 MPa or less. When the storage elastic modulus of the insulating particles at 60 ° C. is equal to or higher than the lower limit and lower than the upper limit, the insulating reliability and conduction reliability can be further effectively enhanced when the electrodes are electrically connected. Can be done.

The storage elastic modulus of the insulating particles at 60 ° C. can be measured by a dynamic viscoelasticity measuring device (“RSA3” manufactured by TA Instruments). The measurement by the above dynamic viscoelasticity measuring device uses a measurement sample having a length of 10 mm, a width of 1 mm to 10 mm, and a thickness of 15 mm to 50 mm, and has a frequency of 10 Hz, a strain of 1%, a temperature of -10 ° C to 210 ° C, and a temperature rise rate. The condition is 5 ° C./min. From the measurement result, the storage elastic modulus at 60 ° C. is calculated. The measurement sample is prepared using the same raw material (material constituting the insulating particles) as the insulating particles.

When the storage elastic modulus of the insulating particles at 60 ° C. is 100 MPa or more and 1000 MPa or less, the insulating particles exhibit a flexible property at 60 ° C. When the storage elastic modulus of the insulating particles at 60 ° C. is in the above-mentioned preferable range, the insulating particles exhibit a very flexible property at 60 ° C. Further, since the temperature at which the insulating particles are arranged on the surface of the conductive particles is about 60 ° C., when the insulating particles are arranged on the surface of the conductive particles, the insulating properties are obtained. The particles become very flexible and can be easily placed on the surface of the conductive particles. Further, since the insulating particles can be easily arranged on the surface of the conductive particles, it is not necessary to use a coating such as an organic compound or an inorganic oxide. Therefore, at the time of conductive connection, the insulating particles are easily detached from the surface of the conductive particles, and the conduction reliability between the upper and lower electrodes to be connected can be effectively improved.

Examples of the method for adjusting the storage elastic modulus of the insulating particles at 60 ° C. to 100 MPa or more and 1000 MPa or less include the following methods. A method for producing insulating particles by adjusting the glass transition temperature of a monomer. A method for producing insulating particles by mixing a main monomer and a monomer having a glass transition temperature different from the glass transition temperature of the main monomer. A method for reducing the addition rate of a cross-linking agent to a main monomer. A method in which a cross-linking agent having a small functional number is used when producing insulating particles. A method using insulating particles having a porous structure. A method using insulating particles having a hollow structure. A method using insulating particles formed of an organic compound different from both ceramics and silica. Methods other than these may be used.

Further, from the viewpoint of setting the storage elastic modulus of the insulating particles at 60 ° C. in the above preferable range, the insulating particles are preferably obtained by polymerizing a polymerizable compound. Examples of the polymerizable compound include the above-mentioned materials for resin particles. The side chain of the polymerizable compound is preferably long. Since the side chain of the polymerizable compound is long, insulating particles exhibiting even more flexible properties can be obtained. Further, as described above, the insulating particles are relatively large. In order to obtain insulating particles having a large particle size, it is preferable that the side chain of the polymerizable compound is short. Insulating particles having a large particle size can be easily obtained by polymerizing a polymerizable compound having a short side chain, but insulating particles obtained from a polymerizable compound having a short side chain exhibit flexible properties. It is difficult to make them. Therefore, as a method of imparting flexible properties to the insulating particles obtained by the polymerizable compound having a short side chain, the polymerizable compound having a short side chain is not involved in the polymerization of the polymerizable compound and has an epoxy group or the like. Examples thereof include a method of introducing a reactive functional group having reactivity with. By introducing the above-mentioned reactive functional group into a polymerizable compound having a short side chain, a polymerizable compound having a short side chain is polymerized to obtain insulating particles, and then the above-mentioned reactive functional group and a compound having a long chain length are combined. By reacting with, it is possible to impart flexible properties to the insulating particles. As a result, the insulating particles can be easily arranged on the surface of the conductive particles.

The swelling ratio of the insulating particles is preferably 1 or more, more preferably 1.2 or more, preferably 2.5 or less, and more preferably 2 or less. When the swelling ratio is equal to or higher than the lower limit, the insulating particles can be more easily arranged on the surface of the conductive particles. When the swelling ratio is not more than the above upper limit, the insulation reliability and the conduction reliability can be further effectively improved when the electrodes are electrically connected.

The swelling ratio is an index of the flexibility of the insulating particles. The higher the swelling ratio, the more flexible the insulating particles are.

The swelling ratio can be measured as follows.

Using the same raw material (material constituting the insulating particles) as the insulating particles, a measurement sample having a length of 10 mm, a width of 5 mm, and a thickness of 0.5 mm is prepared. The weight of the obtained measurement sample is weighed and immersed in 100 g of toluene at 25 ° C. for 20 hours. Then, the measurement sample is taken out, dried at 160 ° C. for 30 minutes, and the weight of the measurement sample after drying is measured. The swelling ratio can be calculated by the following formula (1) from the weight change of the measurement sample before and after immersion in toluene.

Swelling ratio = [Weight of measurement sample after immersion in toluene (g) / Weight of measurement sample before immersion in toluene (g)] ・ ・ ・ Equation (1)

From the viewpoint of further effectively enhancing the insulation reliability and conduction reliability when the electrodes are electrically connected, 10% or more of the total number of the insulating particles is the other insulating particles. It is preferable that the conductive particles are arranged on the surface of the conductive particles so as not to come into contact with the particles. From the viewpoint of further effectively enhancing the insulation reliability and conduction reliability when the electrodes are electrically connected, 30% or more of the total number of the insulating particles is the other insulating particles. It is more preferable that the conductive particles are arranged on the surface of the conductive particles so as not to come into contact with the particles.

The ratio of the number of insulating particles that are not in contact with other insulating particles is preferably calculated by observing 20 conductive particles with insulating particles with a scanning electron microscope (SEM). Specifically, the conductive particles with insulating particles are observed from one direction with a scanning electron microscope (SEM), and the number of insulating particles in each conductive particle with insulating particles and contact with other insulating particles. It is preferable to calculate the number of non-insulating particles and calculate the average value.

Examples of the material constituting the insulating particles include an insulating resin and the like. Examples of the insulating resin include a resin particle material that can be used as a base particle.

Specific examples of the insulating resin that is the material of the insulating particles include a polyolefin compound, a (meth) acrylate polymer, a (meth) acrylate copolymer, a block polymer, a thermoplastic resin, a crosslinked product of a thermoplastic resin, and heat. Examples thereof include curable resins and water-soluble resins.

Examples of the polyolefin compound include polyethylene, ethylene-vinyl acetate copolymer and ethylene-acrylic acid ester copolymer. Examples of the (meth) acrylate polymer include polymethyl (meth) acrylate, polyethyl (meth) acrylate, and polybutyl (meth) acrylate. Examples of the block polymer include polystyrene, styrene-acrylic acid ester copolymer, SB type styrene-butadiene block copolymer, SBS type styrene-butadiene block copolymer, and hydrogenated products thereof. Examples of the thermoplastic resin include vinyl polymers and vinyl copolymers. Examples of the thermosetting resin include epoxy resin, phenol resin, melamine resin and the like. Examples of the water-soluble resin include polyvinyl alcohol, polyacrylic acid, polyacrylamide, polyvinylpyrrolidone, polyethylene oxide, methyl cellulose and the like.

When the storage elastic modulus of the insulating particles at 60 ° C. is adjusted by a cross-linking agent, it is preferable that the material constituting the insulating particles contains a cross-linking agent. From the viewpoint of adjusting the storage elastic modulus at 60 ° C. to 100 MPa or more and 1000 MPa or less, the cross-linking agent is preferably a bifunctional to hexa-functional cross-linking agent. The bifunctional to hexafunctional cross-linking agent is preferably a bifunctional to hexafunctional (meth) acrylate monomer, more preferably a bifunctional to tetrafunctional (meth) acrylate monomer, and 2 More preferably, it is a monomer of a functional (meth) acrylate. As the bifunctional to hexafunctional (meth) acrylate monomer, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate or dimethacrylate ethylene glycol is preferable, and dimethacrylate ethylene glycol is more preferable.

From the viewpoint of easily adjusting the storage elastic modulus of the insulating particles at 60 ° C. to 100 MPa or more and 1000 MPa or less, the cross-linking agent is contained in 100 parts by weight of the material having the highest content among the materials constituting the insulating particles. The amount is preferably 0.001 part by weight or more, more preferably 0.01 part by weight or more, and further preferably 0.1 part by weight or more. From the viewpoint of easily adjusting the storage elastic modulus of the insulating particles at 60 ° C. to 100 MPa or more and 1000 MPa or less, the cross-linking agent is contained in 100 parts by weight of the material having the highest content among the materials constituting the insulating particles. The amount is preferably 20 parts by weight or less, more preferably 10 parts by weight or less, still more preferably 6 parts by weight or less.

Examples of the method for arranging the insulating particles on the surface of the conductive portion include a chemical method and a physical or mechanical method. Examples of the chemical method include an interfacial polymerization method, a suspension polymerization method in the presence of particles, and an emulsion polymerization method. Examples of the physical or mechanical method include spray drying, hybridization, electrostatic adhesion method, spraying method, dipping and vacuum deposition methods. From the viewpoint of further effectively enhancing the insulation reliability and the conduction reliability when the electrodes are electrically connected, the method of arranging the insulating particles on the surface of the conductive portion is a physical method. It is preferable to have.

The outer surface of the conductive portion and the outer surface of the insulating particles may each be coated with a compound having a reactive functional group. The outer surface of the conductive portion and the outer surface of the insulating particles may not be directly chemically bonded, or may be indirectly chemically bonded by a compound having a reactive functional group. After introducing a carboxyl group into the outer surface of the conductive portion, the carboxyl group may be chemically bonded to a functional group on the outer surface of the insulating particles via a polymer electrolyte such as polyethyleneimine.

In the conductive particles with insulating particles according to the present invention, two or more kinds of insulating particles having different particle diameters may be used in combination. By using two or more kinds of insulating particles having different particle diameters in combination, the insulating particles having a small particle size enter into the gaps covered with the insulating particles having a large particle size, and the above-mentioned covering ratio is made more effective. Can be enhanced.

The coefficient of variation (CV value) of the particle size of the insulating particles is preferably 20% or less. When the fluctuation coefficient of the particle size of the insulating particles is not more than the above upper limit, the thickness of the portion of the obtained conductive particles with insulating particles covered with the insulating particles becomes more uniform, and at the time of conductive connection, The pressure can be applied uniformly more easily, and the connection resistance between the electrodes can be further reduced.

The coefficient of variation (CV value) can be measured as follows.

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

The shape of the insulating particles is not particularly limited. The shape of the insulating particles may be spherical, non-spherical, flat or the like.

(Conductive material)
The conductive material according to the present invention includes the above-mentioned conductive particles with insulating particles and a binder resin. The conductive particles with insulating particles are preferably dispersed in a binder resin and used, and preferably dispersed in a binder resin and used as a conductive material. The conductive material is preferably an anisotropic conductive material. The conductive material is preferably used for electrical connection between electrodes. The conductive material is preferably a conductive material for circuit connection. Since the above-mentioned conductive particles with insulating particles are used in the above-mentioned conductive material, the insulation reliability and conduction reliability between the electrodes can be further improved.

The binder resin is not particularly limited. As the binder resin, a known insulating resin is used. The binder resin preferably contains a thermoplastic component (thermoplastic compound) or a curable component, and more preferably contains a curable component. Examples of the curable component include a photocurable component and a thermosetting component. The photocurable component preferably contains a photocurable compound and a photopolymerization initiator. The thermosetting component preferably contains a thermosetting compound and a thermosetting agent.

Examples of the binder resin include vinyl resins, thermoplastic resins, curable resins, thermoplastic block copolymers, and elastomers. Only one kind of the binder resin may be used, or two or more kinds may be used in combination.

Examples of the vinyl resin include vinyl acetate resin, acrylic resin, styrene resin and the like. Examples of the thermoplastic resin include polyolefin resins, ethylene-vinyl acetate copolymers, and polyamide resins. Examples of the curable resin include epoxy resin, urethane resin, polyimide resin, unsaturated polyester resin and the like. The curable resin may be a room temperature curable resin, a thermosetting resin, a photocurable resin, or a moisture curable resin. The curable resin may be used in combination with a curing agent. Examples of the thermoplastic block copolymer include a styrene-butadiene-styrene block copolymer, a styrene-isoprene-styrene block copolymer, a hydrogenated additive of a styrene-butadiene-styrene block copolymer, and a styrene-isoprene. -Hydrogen additives for styrene block copolymers and the like can be mentioned. Examples of the elastomer include styrene-butadiene copolymer rubber and acrylonitrile-styrene block copolymer rubber.

In addition to the conductive particles with insulating particles and the binder resin, the conductive material includes, for example, a filler, a bulking agent, a softener, a plasticizer, a polymerization catalyst, a curing catalyst, a colorant, an antioxidant, and a heat stabilizer. It may contain various additives such as an agent, a light stabilizer, an ultraviolet absorber, a lubricant, an antistatic agent and a flame retardant.

As a method for dispersing the conductive particles with insulating particles in the binder resin, a conventionally known dispersion method can be used and is not particularly limited. Examples of the method for dispersing the conductive particles with insulating particles in the binder resin include the following methods. A method in which the conductive particles with insulating particles are added to the binder resin and then kneaded and dispersed with a planetary mixer or the like. A method in which the conductive particles with insulating particles are uniformly dispersed in water or an organic solvent using a homogenizer or the like, added to the binder resin, and kneaded and dispersed by a planetary mixer or the like. A method in which the binder resin is diluted with water or an organic solvent, the conductive particles with insulating particles are added, and the binder resin is kneaded and dispersed with a planetary mixer or the like.

The viscosity (η25) of the conductive material at 25 ° C. is preferably 30 Pa · s or more, more preferably 50 Pa · s or more, preferably 400 Pa · s or less, and more preferably 300 Pa · s or less. When the viscosity of the conductive material at 25 ° C. 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 is further effective. Can be enhanced to. The viscosity (η25) can be appropriately adjusted depending on the type and amount of the compounding component.

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 conductive material according to the present invention can be used as a conductive paste, a conductive film, or the like. When the conductive material according to the present invention is a conductive film, a film containing no conductive particles may be laminated on the conductive film containing the conductive particles. The conductive paste is preferably an anisotropic conductive paste. The conductive film is preferably an anisotropic conductive film.

The content of the binder resin in 100% by weight of the conductive material is preferably 10% by weight or more, more preferably 30% by weight or more, still more preferably 50% by weight or more, and particularly preferably 70% by weight or more. Is 99.99% by weight or less, more preferably 99.9% by weight or less. When the content of the binder resin is not less than the above lower limit and not more than the above upper limit, the conductive particles are efficiently arranged between the electrodes, and the connection reliability of the connection target member connected by the conductive material is further enhanced. Can be done.

The content of the conductive particles with insulating particles in 100% by weight of the conductive material is preferably 0.01% by weight or more, more preferably 0.1% by weight or more, and preferably 80% by weight or less. It is preferably 60% by weight or less, more preferably 40% by weight or less, particularly preferably 20% by weight or less, and most preferably 10% by weight or less. When the content of the conductive particles with insulating particles is not less than the above lower limit and not more than the above upper limit, the conduction reliability and the insulation reliability between the electrodes can be further improved.

(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 is provided with a connecting portion for connecting 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 particles with insulating particles, or the conductive material containing the above-mentioned conductive particles with insulating particles and a binder resin. In the connection structure according to the present invention, the first electrode and the second electrode are electrically connected by the conductive portion of the conductive particles with insulating particles.

The connection structure is formed by thermocompression bonding with a step of arranging the conductive particles with insulating particles or the conductive material between the first connection target member and the second connection target member. It can be obtained through a step of conducting conductive connection. At the time of thermocompression bonding, it is preferable that the insulating particles are separated from the conductive particles with insulating particles.

FIG. 4 is a cross-sectional view schematically showing a connection structure using conductive particles with insulating particles according to the first embodiment of the present invention.

The connection structure 81 shown in FIG. 4 is a connection portion connecting the first connection target member 82, the second connection target member 83, the first connection target member 82, and the second connection target member 83. It is equipped with 84. The connecting portion 84 is formed of a conductive material containing the conductive particles 1 with insulating particles. The connecting portion 84 is preferably formed by curing a conductive material containing a plurality of conductive particles 1 with insulating particles. In FIG. 4, the conductive particles 1 with insulating particles are shown schematically for convenience of illustration. Instead of the conductive particles 1 with insulating particles, the conductive particles 21 or 41 with insulating particles may be used.

The first connection target member 82 has a plurality of first electrodes 82a on the surface (upper surface). The second connection target member 83 has a plurality of second electrodes 83a on the surface (lower surface). The first electrode 82a and the second electrode 83a are electrically connected by the conductive particles 2 in the conductive particles 1 with one or more insulating particles. Therefore, the first connection target member 82 and the second connection target member 83 are electrically connected by the conductive portion of the conductive particles 1 with insulating particles.

The method for manufacturing the connection structure is not particularly limited. As an example of a method for manufacturing a connection structure, the conductive material is arranged between a first connection target member and a second connection target member, and after obtaining a laminate, the laminate is heated and pressurized. The method and the like can be mentioned. The thermocompression bonding pressure is preferably 40 MPa or more, more preferably 60 MPa or more, preferably 90 MPa or less, and more preferably 70 MPa or less. The heating temperature of the thermocompression bonding is preferably 80 ° C. or higher, more preferably 100 ° C. or higher, preferably 140 ° C. or lower, and more preferably 120 ° C. or lower. When the pressure and temperature of the thermocompression bonding are equal to or higher than the lower limit and lower than the upper limit, the insulating particles can be easily separated from the surface of the conductive particles with insulating particles at the time of conductive connection, and the conduction reliability between the electrodes can be improved. It can be further enhanced.

When the laminate is heated and pressurized, the insulating particles existing between the conductive particles and the first electrode and the second electrode can be eliminated. For example, during the heating and pressurization, the insulating particles existing between the conductive particles and the first electrode and the second electrode are conductive with the insulating particles. Easily detached from the surface of the particles. At the time of heating and pressurizing, some of the insulating particles may be separated from the surface of the conductive particles with insulating particles, and the surface of the conductive portion may be partially exposed. When the exposed surface of the conductive portion comes into contact with the first electrode and the second electrode, the first electrode and the second electrode are electrically connected via the conductive particles. can do.

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

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 member to be connected 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 electrode is preferably an aluminum electrode, a copper electrode, a molybdenum electrode, a silver electrode, or a tungsten electrode. 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.

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.

(Example 1)
(1) Preparation of Conductive Particles Resin particles (particle size 20 μm) formed of a copolymer resin of tetramethylolmethane tetraacrylate and divinylbenzene were prepared. 10 parts by weight of the base material particles were dispersed in 100 parts by weight of an alkaline solution containing 5% by weight of the palladium catalyst solution using an ultrasonic disperser, and then the base material particles were taken out by filtering the solution. Next, the base material particles were added to 100 parts by weight of a 1% by weight solution of dimethylamine borane to activate the surface of the base material particles. After thoroughly washing the surface-activated substrate particles with water, the particles were added to 500 parts by weight of distilled water and dispersed to obtain a dispersion liquid. Next, 1 g of a nickel particle slurry (average particle size 100 nm) was added to the dispersion over 3 minutes to obtain a suspension containing base particles to which a core substance was attached.

Further, a nickel plating solution (pH 8.5) containing nickel sulfate 0.35 mol / L, dimethylamine borane 1.38 mol / L and sodium citrate 0.5 mol / L was prepared.

While stirring the obtained suspension at 70 ° C., the nickel plating solution was gradually added dropwise to the suspension to perform electroless nickel plating. Then, the suspension is filtered to take out the particles, washed with water, and dried to obtain particles having a first conductive portion (nickel-boron layer, thickness 200 nm) formed on the surface of the substrate particles. rice field.

A suspension was obtained by adding 10 parts by weight of the particles on which the first conductive part was formed to 100 parts by weight of distilled water and dispersing them. Further, a reduced gold plating solution containing 0.03 mol / L of gold cyanide and 0.1 mol / L of hydroquinone as a reducing agent was prepared. While stirring the obtained suspension at 70 ° C., the reduced gold plating solution was gradually added dropwise to the suspension to perform reduced gold plating. Then, the suspension was filtered to take out the particles, washed with water, and dried to obtain conductive particles. In the obtained conductive particles, a second conductive portion (gold layer, thickness 35 nm) was formed on the outer surface of the first conductive portion.

(2) Preparation of Insulating Particles After putting the following composition in a 2000 mL separable flask equipped with a four-mouth separable cover, a stirring blade, a three-way cock, a cooling tube and a temperature probe, the above composition is added to the solid content. Distilled water was added so as to be 10% by weight, the mixture was stirred at 120 rpm, and polymerization was carried out at 50 ° C. for 5 hours under a nitrogen atmosphere. The composition comprises 1080 mmol of methyl methacrylate, 10 mmol of ethylene glycol dimethacrylate (crosslinking agent), 0.5 mmol of 4- (methacrylicloyloxy) phenyldimethylsulfonium methylsulfate, and 2,2'-azobis {2- [N-]. (2-carboxyethyl) amidino] propane} contains 0.5 mmol. After completion of the reaction, the reaction was freeze-dried to obtain insulating particles (particle size 540 nm) having a sulfone group derived from 4- (methacryloyloxy) phenyldimethylsulfonium methylsulfate on the surface.

(3) Preparation of Conductive Particles with Insulating Particles The insulating particles obtained above were dispersed in distilled water under ultrasonic irradiation to obtain a 10 wt% aqueous dispersion of insulating particles. 10 g of the obtained conductive particles were dispersed in 500 mL of distilled water, 1 g of a 10 wt% aqueous dispersion of insulating particles was added, and the mixture was stirred at room temperature for 8 hours. After filtering with a 3 μm mesh filter, the mixture was further washed with methanol and dried to obtain conductive particles with insulating particles.

(4) Preparation of Conductive Material (Anisically Conductive Paste) 7 parts by weight of the obtained conductive particles, 25 parts by weight of bisphenol A type phenoxy resin, 4 parts by weight of fluorene type epoxy resin, and 30 parts by weight of phenol novolac type epoxy resin. A conductive material (anisotropic conductive paste) was obtained by blending a part by weight and SI-60L (manufactured by Sanshin Chemical Industry Co., Ltd.), defoaming and stirring for 3 minutes.

(5) Preparation of Connection Structure A transparent glass substrate having an IZO electrode pattern (first electrode, Vickers hardness of metal on the electrode surface of 100 Hv) having an L / S of 10 μm / 10 μm formed on the upper surface was prepared. Further, a semiconductor chip having an Au electrode pattern (second electrode, Vickers hardness of metal on the electrode surface 50 Hv) having an L / S of 10 μm / 10 μm formed on the lower surface was prepared.

The obtained anisotropic conductive paste was coated on the transparent glass substrate so as to have a thickness of 30 μm to form an anisotropic conductive paste layer. Next, the semiconductor chips were laminated on the anisotropic conductive paste layer so that the electrodes face each other. After that, while adjusting the temperature of the head so that the temperature of the anisotropic conductive paste layer becomes 100 ° C., the pressure heating head is placed on the upper surface of the semiconductor chip, and a pressure of 60 MPa is applied to form the anisotropic conductive paste layer. It was cured at 100 ° C. to obtain a connecting structure.

(Example 2)
At the time of preparing the insulating particles, the blending amount of methyl methacrylate in the composition was changed from 1080 mmol to 540 mmol, and 540 mmol of glycidyl methacrylate was added to the composition. Further, when the insulating particles were produced, the particle size of the insulating particles was changed to 750 nm. Except for the above changes, conductive particles, conductive particles with insulating particles, a conductive material, and a connecting structure were obtained in the same manner as in Example 1.

(Example 3)
At the time of preparing the insulating particles, the blending amount of methyl methacrylate in the composition was changed from 1080 mmol to 540 mmol, and 540 mmol of glycidyl methacrylate was added to the composition. Further, when the insulating particles were produced, the particle size of the insulating particles was changed to 800 nm. Except for the above changes, conductive particles, conductive particles with insulating particles, a conductive material, and a connecting structure were obtained in the same manner as in Example 1.

(Example 4)
At the time of preparing the insulating particles, the blending amount of methyl methacrylate in the composition was changed from 1080 mmol to 540 mmol, and 540 mmol of glycidyl methacrylate was added to the composition. Further, when the insulating particles were produced, the particle size of the insulating particles was changed to 1400 nm. Except for the above changes, conductive particles, conductive particles with insulating particles, a conductive material, and a connecting structure were obtained in the same manner as in Example 1.

(Example 5)
When the conductive particles were produced, the thickness of the first conductive portion (nickel-boron layer) was changed to 250 nm, and the second conductive portion (gold layer, thickness 35 nm) was not formed. In the same manner as in Example 3, conductive particles, conductive particles with insulating particles, a conductive material, and a connecting structure were obtained.

(Example 6)
Conductive particles, conductive particles with insulating particles, conductive material, and connecting structure, as in Example 3, except that a nickel particle slurry (average particle diameter of 100 nm) was not used in the production of the conductive particles. I got a body.

(Example 7)
Conductive particles and insulating properties are the same as in Example 3, except that a nickel particle slurry (average particle size 250 nm) is used instead of the nickel particle slurry (average particle size 100 nm) when producing the conductive particles. Conductive particles with particles, conductive materials and connecting structures were obtained.

(Example 8)
Conductive particles and insulating properties are the same as in Example 3, except that a nickel particle slurry (average particle size 450 nm) is used instead of the nickel particle slurry (average particle size 100 nm) when producing the conductive particles. Conductive particles with particles, conductive materials and connecting structures were obtained.

(Example 9)
In the production of conductive particles, instead of the resin particles (particle size 20 μm) formed by the copolymer resin of tetramethylolmethanetetraacrylate and divinylbenzene, the copolymer resin of tetramethylolmethanetetraacrylate and divinylbenzene. Resin particles (particle size 3 μm) formed by the above were used. Except for the above changes, conductive particles, conductive particles with insulating particles, a conductive material, and a connecting structure were obtained in the same manner as in Example 3.

(Example 10)
At the time of producing the conductive particles, the thickness of the first conductive portion (nickel-boron layer) was changed to 250 nm, and the second conductive portion (gold layer, thickness 35 nm) was not formed. Further, in the production of the conductive particles, instead of the resin particles (particle size 20 μm) formed by the copolymer resin of tetramethylolmethanetetraacrylate and divinylbenzene, the tetramethylolmethanetetraacrylate and divinylbenzene are used together. Resin particles (particle size 3 μm) formed of a polymer resin were used. Except for the above changes, conductive particles, conductive particles with insulating particles, a conductive material, and a connecting structure were obtained in the same manner as in Example 3.

(Example 11)
In the production of conductive particles, instead of the resin particles (particle size 20 μm) formed by the copolymer resin of tetramethylolmethanetetraacrylate and divinylbenzene, the copolymer resin of tetramethylolmethanetetraacrylate and divinylbenzene. Resin particles (particle size 10 μm) formed by the above were used. Except for the above changes, conductive particles, conductive particles with insulating particles, a conductive material, and a connecting structure were obtained in the same manner as in Example 3.

(Example 12)
In the production of conductive particles, instead of the resin particles (particle size 20 μm) formed by the copolymer resin of tetramethylolmethanetetraacrylate and divinylbenzene, the copolymer resin of tetramethylolmethanetetraacrylate and divinylbenzene. Resin particles (particle size 35 μm) formed by the above were used. Except for the above changes, conductive particles, conductive particles with insulating particles, a conductive material, and a connecting structure were obtained in the same manner as in Example 3.

(Example 13)
In the production of conductive particles, instead of the resin particles (particle size 20 μm) formed by the copolymer resin of tetramethylolmethanetetraacrylate and divinylbenzene, the copolymer resin of tetramethylolmethanetetraacrylate and divinylbenzene. Resin particles (particle size 50 μm) formed by the above were used. Except for the above changes, conductive particles, conductive particles with insulating particles, a conductive material, and a connecting structure were obtained in the same manner as in Example 3.

(Example 14)
In the preparation of the insulating particles, the amount of methyl methacrylate in the composition was changed from 1080 mmol to 80 mmol, and 1000 mmol of glycidyl methacrylate was added to the composition. Similarly, conductive particles, conductive particles with insulating particles, conductive materials and connecting structures were obtained.

(Example 15)
In the preparation of the insulating particles, the amount of methyl methacrylate in the composition was changed from 1080 mmol to 680 mmol, and 400 mmol of glycidyl methacrylate was added to the composition. Similarly, conductive particles, conductive particles with insulating particles, conductive materials and connecting structures were obtained.

(Example 16)
Conductive particles and conductive particles with insulating particles are the same as in Example 3 except that the blending amount of ethylene glycol dimethacrylate in the above composition was changed from 10 mmol to 15 mmol when the insulating particles were produced. Particles, conductive materials and connecting structures were obtained.

(Example 17)
Conductive particles and conductive particles with insulating particles are the same as in Example 3, except that the blending amount of ethylene glycol dimethacrylate in the above composition was changed from 10 mmol to 20 mmol when the insulating particles were produced. Particles, conductive materials and connecting structures were obtained.

(Comparative Example 1)
Similar to Example 1, conductive particles, conductive particles with insulating particles, conductive materials, and connecting structures are used, except that the particle size of the insulating particles is changed to 450 nm when the insulating particles are produced. Obtained.

(Comparative Example 2)
Similar to Example 3, conductive particles, conductive particles with insulating particles, conductive materials, and connecting structures are used, except that the particle size of the insulating particles is changed to 450 nm when the insulating particles are produced. Obtained.

(Comparative Example 3)
Similar to Example 3, conductive particles, conductive particles with insulating particles, conductive materials, and connecting structures are used, except that the particle size of the insulating particles is changed to 360 nm when the insulating particles are produced. Obtained.

(Comparative Example 4)
At the time of preparing the insulating particles, the blending amount of methyl methacrylate in the composition was changed from 1080 mmol to 540 mmol, and 540 mmol of glycidyl methacrylate was added to the composition. Further, when the insulating particles were produced, the particle size of the insulating particles was changed to 2500 nm. Except for the above changes, conductive particles, conductive particles with insulating particles, a conductive material, and a connecting structure were obtained in the same manner as in Example 1.

(Comparative Example 5)
During the preparation of the insulating particles, 100 mmоl of dipentaerythritol hexaacrylate was added to the above composition. Further, when the insulating particles were produced, the particle size of the insulating particles was changed to 800 nm. Except for the above changes, conductive particles, conductive particles with insulating particles, a conductive material, and a connecting structure were obtained in the same manner as in Example 1.

(Comparative Example 6)
In the preparation of the insulating particles, 1080 mmоl of 2-ethylhexyl methacrylate was added to the above composition instead of 1080 mmol of methyl methacrylate. Further, when the insulating particles were produced, the particle size of the insulating particles was changed to 800 nm. Except for the above changes, conductive particles, conductive particles with insulating particles, a conductive material, and a connecting structure were obtained in the same manner as in Example 1.

(evaluation)
(1) Particle size of insulating particles The particle size of the obtained insulating particles was determined by observing 50 arbitrary insulating particles with an electron microscope and calculating an average value.

(2) Storage elastic modulus of insulating particles at 60 ° C. Measurement of length 10 mm, width 1 mm to 10 mm, thickness 15 mm to 50 mm using the same raw material (material constituting the insulating particles) as the obtained insulating particles. A sample was prepared. Using a dynamic viscoelasticity measuring device (“RSA3” manufactured by TA Instruments), the storage elastic modulus of the above measurement sample at 60 ° C. was measured at a frequency of 10 Hz, a strain of 1%, a temperature of -10 ° C. to 210 ° C., and a heating rate. The measurement was performed under the condition of 5 ° C./min. From the measurement results, the storage elastic modulus at 60 ° C. was calculated.

The measurement sample was prepared as follows. A 30 mm × 40 mm silicone rubber having a hollowed-out center was prepared in the shape of the size of the measurement sample (length 10 mm, width 1 mm to 10 mm, thickness 15 mm to 50 mm). The silicone rubber was placed on a 30 mm × 40 mm glass section. The same raw material (material constituting the insulating particles) as the insulating particles was poured into the hollowed out portion of the silicone rubber on the glass section. A laminate was obtained by covering the silicone rubber into which the same raw material as the insulating particles was poured with a glass section having a size of 30 mm × 40 mm and fixing the mixture with a clip. The obtained laminate was placed in an oven and reacted at 50 ° C. for 5 hours in a nitrogen atmosphere. After the reaction, the clip was removed and the measurement sample was taken out.

(3) Expansion Ratio of Insulating Particles Using the same raw material as the obtained insulating particles, a measurement sample having a length of 10 mm, a width of 5 mm, and a thickness of 0.5 mm was prepared. The weight of the obtained measurement sample was weighed and immersed in 100 g of toluene at 25 ° C. for 20 hours. Then, the measurement sample was taken out and dried at 160 ° C. for 30 minutes, and the weight of the measurement sample after drying was measured. The swelling ratio was calculated by the following formula (1) from the weight change of the measurement sample before and after immersion in toluene.

Swelling ratio = [Weight of measurement sample after immersion in toluene (g) / Weight of measurement sample before immersion in toluene (g)] ・ ・ ・ Equation (1)

(4) Percentage of the total number of insulating particles arranged on the surface of the conductive particles so as not to come into contact with other insulating particles X
The obtained conductive particles with insulating particles were observed with a scanning electron microscope (SEM), and the number of insulating particles in the 20 conductive particles with insulating particles and the contact with other insulating particles were observed. The number of non-insulating particles was calculated respectively. From the obtained results, the ratio X of the number of insulating particles arranged on the surface of the conductive particles so as not to come into contact with other insulating particles among the total number of insulating particles is set to 20. It was calculated as the average value of conductive particles with insulating particles. The ratio X of the above number was determined according to the following criteria.

[Criteria for determining the ratio X of the number of insulating particles arranged on the surface of the conductive particles so as not to come into contact with other insulating particles among the total number of insulating particles]
AA: Number ratio X is 50% or more A: Number ratio X is 30% or more and less than 50% B: Number ratio X is 10% or more and less than 30% C: Number ratio X is less than 10%

(5) Particle Size of Conductive Particles The particle size of the obtained conductive particles was measured using a "laser diffraction type particle size distribution measuring device" manufactured by HORIBA, Ltd. The particle size of the conductive particles was calculated by averaging the results of 20 measurements.

Further, the ratio of the particle size of the conductive particles to the particle size of the insulating particles was calculated from the measurement results of the particle size of the insulating particles and the particle size of the conductive particles.

(6) Conduction reliability (between the upper and lower electrodes)
The connection resistance between the upper and lower electrodes of the obtained 20 connection structures was measured by the 4-terminal method, respectively. 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]
○ ○ ○: Connection resistance is 2.0Ω or less ○ ○: Connection resistance is more than 2.0Ω and 5.0Ω or less ○: Connection resistance is more than 5.0Ω and 10Ω or less ×: Connection resistance is more than 10Ω

(7) Insulation reliability (between adjacent electrodes in the horizontal direction)
In the 20 connection structures obtained in the above (6) Evaluation of conduction reliability, the presence or absence of leakage between adjacent electrodes was evaluated by measuring the resistance value with a tester. Insulation reliability was evaluated according to the following criteria.

[Criteria for insulation reliability]
○○○: number of resistance 10 ⁸ Omega more connections structures, 18 or more ○○: the number of resistance 10 ⁸ Omega more connection structure is less than 18 15 or more ○: resistance There number of 10 ⁸ Omega more connections structures, 10 or more 15 than ×: number of resistance 10 ⁸ Omega more connection structure is less than 10

The results are shown in Tables 1 to 3 below.

1 ... Conductive particles with insulating particles 2 ... Conductive particles 3 ... Insulating particles 11 ... Base particles 12 ... Conductive parts 21 ... Conductive particles with insulating particles 22 ... Conductive particles 31 ... Conductive parts 32 ... Core material 33 ... Projection 41 ... Conductive particle with insulating particles 42 ... Conductive particle 51 ... Conductive part 52 ... Projection 81 ... Connection structure 82 ... First connection target member 82a ... First electrode 83 ... Second connection target Member 83a ... Second electrode 84 ... Connection

Claims (8)

With conductive particles that have at least a conductive part on the surface,
With a plurality of insulating particles arranged on the surface of the conductive particles,
The particle size of the insulating particles is 500 nm or more and 1500 nm or less.
Conductive particles with insulating particles having a storage elastic modulus of the insulating particles at 60 ° C. of 100 MPa or more and 1000 MPa or less. The conductive particles with insulating particles according to claim 1, wherein the conductive particles have protrusions on the outer surface of the conductive portion. The conductive particle with insulating particles according to claim 1 or 2, wherein the ratio of the particle size of the conductive particles to the particle size of the insulating particles is 3 or more and 100 or less. The conductive particle with insulating particles according to any one of claims 1 to 3, wherein the swelling ratio of the insulating particles is 1 or more and 2.5 or less. Any one of claims 1 to 4, wherein 10% or more of the total number of the insulating particles is arranged on the surface of the conductive particles so as not to come into contact with the other insulating particles. Conductive particles with insulating particles according to. The conductive particle with insulating particles according to any one of claims 1 to 5, wherein the conductive particles have a particle size of 1 μm or more and 50 μm or less. A conductive material containing the conductive particles with insulating particles according to any one of claims 1 to 6 and a binder resin. A first connection target member having a first electrode on its surface,
A second connection target member having a second electrode on the surface,
The first connection target member and the connection portion connecting the second connection target member are provided.
The material of the connecting portion is the conductive particles with insulating particles according to any one of claims 1 to 6, or is a conductive material containing the conductive particles with insulating particles and a binder resin. ,
A connection structure in which the first electrode and the second electrode are electrically connected by the conductive portion of the conductive particles with insulating particles.

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