TWI807064B - Conductive particles with insulating particles, conductive material and connection structure - Google Patents

Abstract

The present invention provides conductive particles with insulating particles that can effectively improve conduction reliability and further effectively improve insulation reliability when electrodes are electrically connected. The conductive particle with insulating particles of the present invention includes at least conductive particles having a conductive portion on the surface, and a plurality of insulating particles arranged on the surface of the conductive particles, and the particle diameter of the insulating particles is 500 nm to 1500 nm, and the storage elastic modulus at 60° C. of the insulating particles is 100 MPa to 1000 MPa.

Description

Conductive particles with insulating particles, conductive material and connection structure

The present invention relates to a conductive particle with insulating particles arranged on the surface of the conductive particle. Also, the present invention relates to a conductive material and a connection structure using the above-mentioned conductive particles with insulating particles.

Anisotropic conductive materials such as anisotropic conductive paste and anisotropic conductive film are widely known. Conductive particles are dispersed in the binder resin in the anisotropic conductive material. Moreover, as electroconductive particle, the electroconductive particle which gave the surface of a conductive layer the insulation process may be used.

The aforementioned anisotropic conductive materials are used to obtain various connection structures. Examples of connection using the above-mentioned anisotropic conductive material include: connection between a flexible printed substrate and a glass substrate (FOG (Film on Glass, coated glass)), connection between a semiconductor chip and a flexible printed substrate (COF (Chip on Film, chip on film)), connection between a semiconductor chip and a glass substrate (COG (Chip on Glass, chip on glass)), and connection between a flexible printed substrate and a glass epoxy substrate (FOB (Film on Board, coated board)), etc. .

Moreover, as said electroconductive particle, the electroconductive particle with insulating particle which arrange|positioned the insulating particle on the surface of electroconductive particle may be used. Furthermore, it may use the coated electroconductive particle which arrange|positioned the insulating layer on the surface of a conductive layer.

As an example of the conductive particle with insulating particle mentioned above, the following patent document 1 discloses the conductive particle with insulating particle which has: the conductive particle which has a conductive layer on the surface, and the insulating particle adhered to the surface of the said conductive particle. In the above-mentioned conductive particle with insulating particle, the above-mentioned insulating particle has a hydroxyl group directly bonded to a phosphorus atom or a hydroxyl group directly bonded to a silicon atom on the surface.

The following Patent Document 2 discloses a conductive particle with insulating particles, which includes: a conductive particle body with insulating particles having conductive particles having at least a conductive portion on the surface and a plurality of insulating particles arranged on the surface of the conductive particle, and a film covering the surface of the conductive particle body with insulating particles. In the electroconductive particle with insulating particle mentioned above, the said coating has the 1st coating part which covers the said electroconductive particle, and the 2nd coating part which covers the surface of the said insulating particle. In the conductive particle with insulating particle mentioned above, the thickness of the said 1st coating part is 1/2 or less of the average particle diameter of the said insulating particle. [Prior Art Literature] [Patent Document]

[Patent Document 1] WO2011/030715A1 [Patent Document 2] Japanese Patent Laid-Open No. 2013-175453

[Problem to be solved by the invention]

When conducting conductive connection using a conductive material containing conductive particles, a plurality of electrodes on the upper side are electrically connected to a plurality of electrodes on the lower side to perform conductive connection. It is preferable that electroconductive particle is arrange|positioned between the upper and lower electrodes, and it is more preferable that it is not arrange|positioned between the electrodes of the adjacent horizontal direction. Preferably, there is no electrical connection between adjacent electrodes in the horizontal direction.

In the conventional conductive particles with insulating particles, although the conductive surface is covered with insulating particles, it is difficult to suppress the electrical connection between electrodes adjacent to the horizontal direction that should not be connected after the conductive connection between the upper and lower electrodes that should be connected. Especially when using the electroconductive particle with a relatively large particle diameter, it may be difficult to fully improve the insulation reliability between the adjacent horizontal direction electrodes in the connection structure connected electrically.

Moreover, the conventional electroconductive particle with insulating particle used the coating film, such as an organic compound or an inorganic oxide, and the insulating particle was arrange|positioned on the surface of electroconductive particle in some cases. If the above coating is used to arrange insulating particles on the surface of the conductive particles, it may be difficult for the insulating particles to detach from the surface of the conductive particles during conductive connection, and it may be difficult to sufficiently improve the conduction reliability between the upper and lower electrodes to be connected. In the conventional conductive particles with insulating particles, it is difficult to effectively improve the conduction reliability between the upper and lower electrodes that should be connected and the insulation reliability between electrodes adjacent to the horizontal direction that should not be connected.

The object of the present invention is to provide conductive particles with insulating particles that can effectively improve conduction reliability and further effectively improve insulation reliability when electrodes are electrically connected. Moreover, the object of this invention is to provide the electrically-conductive material and connection structure using the said electroconductive particle with insulating particle. [Technical means to solve the problem]

According to a broader aspect of the present invention, there is provided a conductive particle with insulating particles, which has at least a conductive particle having a conductive portion on the surface and a plurality of insulating particles arranged on the surface of the conductive particle, and the particle diameter of the insulating particle is 500 nm to 1500 nm, and the storage modulus of elasticity at 60° C. of the insulating particle is 100 MPa to 1000 MPa.

In a specific aspect of the conductive particle with insulating particle of this invention, the said conductive particle has a processus|protrusion on the outer surface of the said conductive part.

In a specific aspect of the electroconductive particle with insulating particle of this invention, the ratio of the particle diameter of the said electroconductive particle with respect to the particle diameter of the said insulating particle is 3 or more and 100 or less.

In a specific aspect of the conductive particle with insulating particle of this invention, the expansion ratio of the said insulating particle is 1 or more and 2.5 or less.

In a specific aspect of the conductive particles with insulating particles of the present invention, 10% or more of the total number of the insulating particles are arranged on the surface of the conductive particles so as not to be in contact with other insulating particles.

In a specific aspect of the conductive particle with insulating particle of this invention, the particle diameter of the said conductive particle is 1 micrometer or more and 50 micrometers or less.

According to a wider 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 broader aspect of the present invention, there is provided a connection structure comprising a first connection object member having a first electrode on its surface, a second connection object member having a second electrode on its surface, and a connection portion connecting the first connection object member to the second connection object member, and the material of the connection portion is the conductive particle with insulating particles, or a conductive material including the conductive particle with insulating particles and a binder resin. The above-mentioned conductive parts are electrically connected. [Effect of Invention]

The electroconductive particle with insulating particle of this invention is provided with the electroconductive particle which has an electroconductive part in the surface at least, and the some insulating particle arrange|positioned on the surface of the said electroconductive particle. In the electroconductive particle with insulating particle of this invention, the particle diameter of the said insulating particle is 500 nm or more and 1500 nm or less. In the electroconductive particle with insulating particle of this invention, the storage elastic modulus in 60 degreeC of the said insulating particle is 100 MPa or more and 1000 MPa or less. In the conductive particle with insulating particle of this invention, since it has the said structure, when electrically connecting between electrodes, conduction reliability can be effectively improved, and furthermore, insulation reliability can be effectively improved.

Hereinafter, the details of the present invention will be described.

(conductive particles with insulating particles) The electroconductive particle with insulating particle of this invention is provided with the electroconductive particle which has an electroconductive part in the surface at least, and the some insulating particle arrange|positioned on the surface of the said electroconductive particle. In the electroconductive particle with insulating particle of this invention, the particle diameter of the said insulating particle is 500 nm or more and 1500 nm or less. In the electroconductive particle with insulating particle of this invention, the storage elastic modulus in 60 degreeC of the said insulating particle is 100 MPa or more and 1000 MPa or less.

In the conductive particle with insulating particle of this invention, since it has the said structure, when electrically connecting between electrodes, conduction reliability can be effectively improved, and furthermore, insulation reliability can be effectively improved.

In the conventional conductive particles with insulating particles, although the conductive surface is covered with insulating particles, it is difficult to suppress the electrical connection between electrodes adjacent to the horizontal direction that should not be connected after the conductive connection between the upper and lower electrodes that should be connected. In particular, when using conductive particles with relatively large particle diameters, there is a problem that the insulation reliability between adjacent electrodes in the horizontal direction in a conductively connected connection structure cannot be sufficiently improved.

As a result of earnest research by the present inventors to solve the above-mentioned problems, it was found that the above-mentioned problems can be solved by using specific insulating particles. In the present invention, since the specific insulating particles are used, the insulation reliability between adjacent electrodes in the horizontal direction in the conductively connected connection structure can be effectively improved.

In addition, in the present invention, by using specific insulating particles, the insulating particles can be effectively arranged on the surface of the conductive particles, so that it is not necessary to use coatings such as organic compounds or inorganic oxides. As a result, during the conductive connection, the insulating particles are easily detached from the surface of the conductive particles, which can effectively improve the conduction reliability between the upper and lower electrodes to be connected. In the present invention, the conduction reliability between the upper and lower electrodes that should be connected and the insulation reliability between the electrodes that should not be connected in the lateral direction can be effectively improved.

In the present invention, in order to obtain the above-mentioned effects, it is very important to use specific insulating particles.

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

The said 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 particle size of conductive particles with insulating particles

The shape of the above-mentioned conductive particles with insulating particles is not particularly limited. The shape of the electroconductive particle with insulating particle mentioned above may be spherical, a shape other than spherical, flat, etc. may be sufficient.

The aforementioned conductive particles with insulating particles dispersed in a binder resin are preferably used to obtain 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 electroconductive particle 1 with an insulating particle shown in FIG. 1 is equipped with the electroconductive particle 2 and the some insulating particle 3 arrange|positioned on the surface of the electroconductive particle 2. As shown in FIG. The insulating particles 3 are formed of an insulating material.

The electroconductive particle 2 has the electroconductive part 12 arrange|positioned on the surface of the base material particle 11 and the base material particle 11. In the conductive particle 1 with insulating particle, the conductive part 12 is a conductive layer. The conductive part 12 covers the surface of the substrate particle 11 . The electroconductive particle 2 is the coated particle which covered the surface of the base material particle 11 with the electroconductive part 12. The electroconductive particle 2 has the electroconductive part 12 on the surface. In the said electroconductive particle, the said electroconductive part may cover the whole surface of the said base material particle, and the said electroconductive part may cover a part of the surface of the said base material particle. In the conductive particle with insulating particle mentioned above, it is preferable that the said insulating particle is arrange|positioned on the surface of the said conductive part.

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

The electroconductive particle 21 with an insulating particle shown in FIG. 2 is equipped with the electroconductive particle 22 and the some insulating particle 3 arrange|positioned on the surface of the electroconductive particle 22. As shown in FIG.

The electroconductive particle 22 has the electroconductive part 31 arrange|positioned on the surface of the base material particle 11 and the base material particle 11. In the conductive particle 21 with insulating particle, the conductive part 31 is a conductive layer. The conductive particle 22 has a plurality of core substances 32 on the surface of the substrate particle 11 . The conductive part 31 covers the base material particle 11 and the core substance 32 . By coating the core material 32 with the conductive part 31, the conductive particle 22 has a plurality of protrusions 33 on the surface. In the electroconductive particle 22, the surface of the electroconductive part 31 is raised by the core substance 32, and the some protrusion 33 is formed. In the said electroconductive particle, the said electroconductive part may cover the whole surface of the said base material particle, and the said electroconductive part may cover a part of the surface of the said base material particle. In the conductive particle with insulating particle mentioned above, it is preferable that the said insulating particle is arrange|positioned on the surface of the said conductive part.

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

The electroconductive particle 41 with insulating particle shown in FIG.

The electroconductive particle 42 has the electroconductive part 51 arrange|positioned on the surface of the base material particle 11 and the base material particle 11. In the conductive particle 41 with insulating particle, the conductive part 51 is a conductive layer. The electroconductive particle 42 does not have a core substance like the electroconductive particle 22 . The conductive part 51 has a 1st part and a 2nd part thicker than this 1st part. The conductive particle 42 has a plurality of protrusions 52 on the surface. The portion other than the plurality of protrusions 52 is the above-mentioned first portion of the conductive portion 51 . The plurality of protrusions 52 are the above-mentioned second portion where the thickness of the conductive portion 51 is relatively thick. In the said electroconductive particle, the said electroconductive part may cover the whole surface of the said base material particle, and the said electroconductive part may cover a part of the surface of the said base material particle. In the conductive particle with insulating particle mentioned above, it is preferable that the said insulating particle is arrange|positioned on the surface of the said conductive part.

Hereinafter, other details of the electroconductive particle with insulating particle are demonstrated.

Conductive Particles: It is preferable that the said electroconductive particle has a base material particle, and the electroconductive part arrange|positioned on the surface of the said base material particle. The above-mentioned conductive portion may have a single-layer structure, or may have a multi-layer structure of two or more layers.

The particle size of the conductive particles is preferably at least 1 μm, more preferably at least 10 μm, and preferably at most 50 μm, more preferably at most 40 μm. When the particle diameter of the said electroconductive particle is more than the said minimum and below the said upper limit, when connecting between electrodes using the said electroconductive particle, the contact area of electroconductive particle and an electrode becomes large enough, and it is difficult to form the electroconductive particle aggregated at the time of forming a conductive part. Moreover, the distance between the electrodes connected via electroconductive particle does not become too large, and it becomes difficult for a conductive part to peel off from the surface of a base material particle.

The particle size of the above-mentioned conductive particles is preferably an average particle size, more preferably a number average particle size. The particle diameter of electroconductive particle can be calculated|required by observing arbitrary 50 electroconductive particles with an electron microscope or an optical microscope, calculating the average value of the particle diameter of each electroconductive particle, or performing a laser diffraction particle size distribution measurement, for example. When measuring the particle diameter of the said electroconductive particle by the method of observing arbitrary 50 electroconductive particles among electroconductive particles with an electron microscope or an optical microscope, it can measure as follows, for example.

This was added and dispersed to "Technovit 4000" manufactured by Kulzer Corporation so that the content of the conductive particles would be 30% by weight, to prepare an embedding resin for conductive particle inspection. The cross section of the conductive particle was cut out using an ion mill ("IM4000" manufactured by Hitachi High-Technologies Co., Ltd.) so as to pass through the vicinity of the center of the conductive particle in the embedded resin for inspection. Then, using a field emission scanning electron microscope (FE-SEM), the image magnification was set to 25000 times, 50 electroconductive particles were randomly selected, and each electroconductive particle was observed. The circle-equivalent diameter of each electroconductive particle was measured as a particle diameter, and the arithmetic mean was made into the particle diameter of electroconductive particle. Instead of the embedded resin for conductive particle inspection, the embedded resin for conductive particle inspection with insulating particles can be produced.

The coefficient of variation (CV value) of the particle diameter of the said electroconductive particle becomes like this. Preferably it is 10% or less, More preferably, it is 5% or less. The conduction reliability and insulation reliability between electrodes can be improved more effectively as the variation coefficient of the particle diameter of the said electroconductive particle is below the said upper limit.

The said 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: The average value of the particle diameter of conductive particles

The shape of the said electroconductive particle is not specifically limited. The shape of the said electroconductive particle may be spherical, the shape other than spherical, flat shape, etc. may be sufficient as it.

Substrate particles: Examples of the substrate particles include resin particles, inorganic particles other than metal particles, organic-inorganic hybrid particles, metal particles, and the like. The aforementioned substrate particles are preferably substrate particles other than metal particles, more preferably resin particles, inorganic particles other than metal particles, or organic-inorganic hybrid particles. The aforementioned substrate particles may be substrate particles other than inorganic particles. The aforementioned substrate particle may also be a core-shell particle having a core and a shell arranged on the surface of the core. The aforementioned core may be an organic core, and the aforementioned shell may be an inorganic shell.

Various organic substances can be preferably used as the material of the above-mentioned resin particles. Examples of materials for the resin particles include polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene, and polybutadiene; acrylic resins such as polymethyl methacrylate and polymethyl acrylate; polycarbonate, polyamide, phenol-formaldehyde resin, melamine-formaldehyde resin, benzoguanamine-formaldehyde resin, urea-formaldehyde resin, phenol resin, melamine resin, benzoguanamine resin, urea resin, epoxy resin, and unsaturated polyester. Resin, saturated polyester resin, polyethylene terephthalate, polyethylene, polyphenylene oxide, polyacetal, polyimide, polyamideimide, polyether ether ketone, polyether ketone, divinylbenzene polymer, and divinylbenzene copolymer, etc. As said divinylbenzene type copolymer etc., a divinylbenzene-styrene copolymer, a divinylbenzene-(meth)acrylate copolymer, etc. are mentioned. Since the hardness of the resin particles can be easily controlled within a preferred range, the material of the resin particles is preferably a polymer obtained by polymerizing one or more polymerizable monomers having ethylenically unsaturated groups.

When polymerizing a polymerizable monomer having an ethylenically unsaturated group to obtain the above-mentioned resin particles, examples of the polymerizable monomer having an ethylenically unsaturated group include non-crosslinkable monomers and crosslinkable monomers.

Examples of non-crosslinkable monomers include: styrene-based monomers such as styrene and α-methylstyrene; 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, and cyclohexyl (meth)acrylate Alkyl (meth)acrylate compounds such as (meth)acrylic acid isomethacrylate; (meth)acrylate compounds containing oxygen atoms such as 2-hydroxyethyl (meth)acrylate, glycerol (meth)acrylate, polyoxyethylene (meth)acrylate, and glycidyl (meth)acrylate; 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 vinyl stearate Compounds; unsaturated hydrocarbons such as ethylene, propylene, isoprene, and butadiene; halogen-containing monomers such as trifluoromethyl (meth)acrylate, pentafluoroethyl (meth)acrylate, vinyl chloride, vinyl fluoride, and chlorostyrene, etc.

Examples of the crosslinkable monomer include tetramethylolmethane tetra(meth)acrylate, tetramethylolmethane tri(meth)acrylate, tetramethylolmethane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate, glycerin tri(meth)acrylate, glycerin di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate ) acrylate, (poly)tetramethylene glycol di(meth)acrylate, and 1,4-butanediol di(meth)acrylate and other polyfunctional (meth)acrylate compounds; (iso)triallyl cyanurate, triallyl trimellitate, divinylbenzene, diallyl phthalate, diallyl acrylamide, diallyl ether, and γ-(meth)acryloxypropyltrimethoxysilane, trimethoxysilylstyrene, and Vinyltrimethoxysilane and other silane-containing monomers, etc.

The term "(meth)acrylate" means acrylate and methacrylate. The term "(meth)acrylic acid" means acrylic acid and methacrylic acid. The term "(meth)acryl" means acryl and methacryl.

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

When the above-mentioned substrate particles are inorganic particles or organic-inorganic hybrid particles other than metal particles, examples of inorganic substances used to form the substrate particles include silicon oxide, aluminum oxide, barium titanate, zirconium oxide, and carbon black. The above-mentioned inorganic substances are preferably not metals. The particles formed from the above-mentioned silicon oxide are not particularly limited, and examples thereof include particles obtained by hydrolyzing a silicon compound having two or more hydrolyzable alkoxysilyl groups to form crosslinked polymer particles, and then calcining as necessary. Examples of the above-mentioned organic-inorganic hybrid particles include organic-inorganic hybrid particles formed of a crosslinked alkoxysilyl polymer and an acrylic resin.

The above-mentioned 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. The aforementioned core is preferably an organic core. The aforementioned shell is preferably an inorganic shell. From the viewpoint of effectively reducing the connection resistance between electrodes, the substrate particle is preferably an organic-inorganic hybrid particle having an organic core and an inorganic shell arranged on the surface of the organic core.

As a material of the said organic core, the material of the said resin particle etc. are mentioned.

Examples of the material of the above-mentioned inorganic shell include the inorganic substances listed as the material of the above-mentioned substrate particle. The material of the above-mentioned inorganic shell is preferably silicon oxide. The above-mentioned inorganic shell is preferably formed by forming a shell-like material from a metal alkoxide on the surface of the above-mentioned core by a sol-gel method, and then calcining the shell-like material. The aforementioned metal alkoxide is preferably a silane alkoxide. The above-mentioned inorganic shell is preferably formed by silane alkoxide.

When the above-mentioned substrate particle is a metal particle, silver, copper, nickel, silicon, gold, titanium, etc. are mentioned as the metal which is a material of this metal particle.

The particle size of the substrate particles is preferably not less than 0.6 μm, more preferably not less than 0.8 μm, and is preferably not more than 49.8 μm, more preferably not more than 49.6 μm. If the particle diameter of the said base material particle is more than the said minimum and below the said upper limit, the gap between electrodes will become small, and even if it increases the thickness of a conductive part (conductive layer etc.), small electroconductive particle can be obtained. Furthermore, when forming an electroconductive part on the surface of a base material particle, it becomes difficult to aggregate, and it becomes difficult to form aggregated electroconductive particle.

The particle diameter of the above-mentioned substrate particles is preferably not less than 0.9 μm and not more than 49.9 μm. When the particle size of the substrate particle is in the range of 0.9 μm to 49.9 μm, it is difficult to aggregate when forming the conductive portion on the surface of the substrate particle, and it is difficult to form aggregated conductive particles.

The particle diameter of the above-mentioned substrate particles represents a number average particle diameter. The particle diameter of the above-mentioned substrate particles is determined using a particle size distribution measuring device or the like. The particle diameter of the substrate particles is preferably obtained by observing arbitrary 50 substrate particles with an electron microscope or an optical microscope, calculating the average particle diameter of each substrate particle, or performing a laser diffraction particle size distribution measurement. When measuring the particle diameter of the said base material particle by the method of observing arbitrary 50 base material particles among electroconductive particles with an electron microscope or an optical microscope, it can measure as follows, for example.

This was added and dispersed to "Technovit 4000" manufactured by Kulzer Corporation so that the content of the conductive particles would be 30% by weight, to prepare an embedding resin for conductive particle inspection. The cross section of the conductive particle was cut out using an ion mill ("IM4000" manufactured by Hitachi High-Technologies Co., Ltd.) so as to pass through the vicinity of the center of the conductive particle in the embedded resin for inspection. Then, using a field emission scanning electron microscope (FE-SEM), the image magnification was set to 25000 times, 50 electroconductive particles were randomly selected, and the substrate particle of each electroconductive particle was observed. The circle-equivalent diameter of the substrate particle in each electroconductive particle was measured as a particle diameter, and the arithmetic mean of these was made into the particle diameter of a substrate particle. Instead of the embedded resin for conductive particle inspection, the embedded resin for conductive particle inspection with insulating particles can be produced.

Conductive part: In this invention, the said electroconductive particle has an electroconductive part in the surface at least. It is preferable that the said conductive part contains metal. The metal constituting the above-mentioned 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. Moreover, tin-doped indium oxide (ITO) can also be used as said metal. The said metal may use only 1 type, and may use 2 or more types together. From the viewpoint of further reducing connection resistance between electrodes, an alloy containing tin, nickel, palladium, copper, or gold is preferable, and nickel or palladium is more preferable.

Also, from the viewpoint of effectively improving 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 part containing nickel is preferably at least 10% by weight, more preferably at least 50% by weight, further preferably at least 60% by weight, still more preferably at least 70% by weight, and most preferably at least 90% by weight. 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 often exist on the surface of the conductive part due to oxidation. Usually, hydroxyl groups exist on the surface of the conductive portion formed of nickel due to oxidation. Insulating particles can be arranged on the surface of the conductive portion (surface of the conductive particle) having such a hydroxyl group via a chemical bond.

The said conductive part can be formed with 1 layer. The above-mentioned conductive part may also be formed by a plurality of layers. That is, the above-mentioned conductive portion may have a laminated structure of two or more layers. In the case where the above-mentioned conductive portion is formed by multiple layers, the metal constituting the outermost layer is preferably gold, nickel, palladium, copper or an alloy including tin and silver, more preferably gold. In the case where the metal constituting the outermost layer is such a preferable metal, the connection resistance between electrodes is further reduced. Also, when the metal constituting the outermost layer is gold, the corrosion resistance is further improved.

The method for forming the conductive portion on the surface of the substrate particle is not particularly limited. As a method of forming the above-mentioned conductive portion, for example, a method using electroless plating, a method using electroplating, a method using physical collision, a method using mechanochemical reaction, a method using physical vapor deposition or physical adsorption, and a method of coating metal powder or a paste containing metal powder and a binder on the surface of the substrate particle, etc. The method of forming the above-mentioned conductive part is preferably a method utilizing electroless plating, electroplating or physical collision. Examples of the method utilizing physical vapor deposition include methods such as vacuum vapor deposition, ion plating, and ion sputtering. In addition, in the above-mentioned method using physical collision, for example, Theta Composer (manufactured by Tokusu Works Co., Ltd.) or the like is used.

The thickness of the conductive portion is preferably at least 0.005 μm, more preferably at least 0.01 μm, more preferably at most 10 μm, more preferably at most 1 μm, and still more preferably at most 0.3 μm. Sufficient electroconductivity is acquired as the thickness of the said electroconductive part is more than the said minimum and below the said upper limit, and electroconductive particle can fully deform|transform electroconductive particle at the time of connection between electrodes, without becoming hard too much.

When the above-mentioned conductive portion is formed by multiple layers, the thickness of the conductive portion of the outermost layer is preferably at least 0.001 μm, more preferably at least 0.01 μm, and is preferably at most 0.5 μm, more preferably at most 0.1 μm. When the thickness of the conductive part of the outermost layer is more than the above-mentioned lower limit and not more than the above-mentioned upper limit, the conductive part of the outermost layer becomes uniform, the corrosion resistance is sufficiently improved, and the connection resistance between electrodes can be sufficiently reduced.

The thickness of the said electroconductive part can be measured by observing the cross-section of electroconductive particle using a transmission electron microscope (TEM), for example.

Core substance: It is preferable that the said electroconductive particle has several protrusions on the outer surface of the said conductive part. An oxide film is often formed on the surface of electrodes connected by conductive particles with insulating particles. In the case of using conductive particles with insulating particles having protrusions on the surface of the conductive part, the above-mentioned oxide film can be effectively removed by the protrusions by arranging the conductive particles with insulating particles between electrodes and performing pressure bonding. Therefore, the electrodes and the conductive parts are brought into more reliable contact, and the connection resistance between the electrodes is further reduced. Furthermore, at the time of connection between electrodes, the protrusion of electroconductive particle can effectively exclude the insulating particle between electroconductive particle and an electrode. Therefore, the conduction reliability between electrodes is further improved.

As a method of forming the above-mentioned protrusions, there may be mentioned: a method of forming a conductive part by electroless plating after attaching a core substance to the surface of the base particle; As another method of forming the above-mentioned protrusions, a method of forming a first conductive portion on the surface of a substrate particle, then disposing a core substance on the first conductive portion, and then forming a second conductive portion; and a method of adding a core substance in the middle of forming a conductive portion (first conductive portion or second conductive portion, etc.) on the surface of a substrate particle, etc. In addition, the following method can also be used: in order to form the protrusions, the above-mentioned core substance is not used, and after the conductive part is formed on the substrate particle by electroless plating, the plating layer is deposited in the shape of a protrusion on the surface of the conductive part, and then the conductive part is formed by electroless plating.

As a method of attaching the core substance to the surface of the substrate particle, for example, a method of adding the core substance to the dispersion of the substrate particle, accumulating and adhering the core substance to the surface of the substrate particle by van der Waals force, adding the core substance into a container containing the substrate particle, and attaching the core substance to the surface of the substrate particle by utilizing mechanical action such as rotation of the container, etc. From the viewpoint of controlling the amount of the adhered core substance, the method of adhering the core substance to the surface of the substrate particle is preferably a method of accumulating and adhering the core substance on the surface of the substrate particle in the dispersion.

As a substance which comprises the said core substance, a conductive substance and a nonconductive substance are mentioned. Examples of the conductive substance include conductive nonmetals such as metals, metal oxides, and graphite, and conductive polymers. Polyacetylene etc. are mentioned as said electroconductive polymer. Examples of the above-mentioned non-conductive substance include silicon oxide, aluminum oxide, and zirconium oxide. From the viewpoint of further improving conduction reliability between electrodes, it is preferable that the core material is metal.

The aforementioned metals are not particularly limited. Examples of the aforementioned metals include metals such as gold, silver, copper, platinum, zinc, iron, lead, tin, aluminum, cobalt, indium, nickel, chromium, titanium, antimony, bismuth, germanium, and cadmium, and alloys containing two or more metals such as tin-lead alloys, tin-copper alloys, tin-silver alloys, tin-lead-silver alloys, and tungsten carbide. From the viewpoint of further improving conduction reliability between electrodes, the above-mentioned metal is preferably nickel, copper, silver or gold. The said metal may be the same as the metal which comprises the said conductive part (conductive layer), and may differ from the metal which comprises the said conductive part (conductive layer).

The shape of the above-mentioned core substance is not particularly limited. The shape of the core substance is preferably block. Examples of the core substance include granular lumps, aggregated lumps in which a plurality of fine particles are aggregated, amorphous lumps, and the like.

The particle size (average particle size) of the core substance is preferably at least 0.001 μm, more preferably at least 0.05 μm, and is preferably at most 0.9 μm, more preferably at most 0.2 μm. The connection resistance between electrodes can be effectively reduced as the particle diameter of the said core substance is more than the said minimum and below the upper limit.

The particle diameter of the aforementioned core substance is preferably an average particle diameter, more preferably a number average particle diameter. The particle diameter of the core substance is obtained by observing 50 arbitrary core substances with an electron microscope or an optical microscope, calculating the average value of the particle diameter of each core substance, or performing a laser diffraction particle size distribution measurement. When measuring the particle diameter of the said core substance by the method of observing arbitrary 50 core substances in electroconductive particle with an electron microscope or an optical microscope, it can measure as follows, for example.

The electroconductive particle was added and dispersed in "Technovit 4000" manufactured by Kulzer company so that the content might become 30 weight%, and it manufactured the embedding resin for electroconductive particle inspection. The cross section of the conductive particle was cut out using an ion mill ("IM4000" manufactured by Hitachi High-Technologies Co., Ltd.) so as to pass through the vicinity of the center of the conductive particle in the embedding resin for inspection. Then, using a field emission scanning electron microscope (FE-SEM), the image magnification was set to 200,000 times, 50 conductive particles were randomly selected, and the core substance of the conductive particles was observed. The circle-equivalent diameter of the core substance in each electroconductive particle was measured as a particle diameter, and the arithmetic mean was made into the particle diameter of the core substance. Instead of the embedded resin for conductive particle inspection, the embedded resin for conductive particle inspection with insulating particles can be produced.

Insulating particles: The electroconductive particle with insulating particle of this invention is equipped with the several insulating particle arrange|positioned on the surface of the said electroconductive particle. In this case, if the electroconductive particle with the said insulating particle is used for connection between electrodes, the short circuit between adjacent electrodes can be prevented. Specifically, when a plurality of conductive particles with insulating particles are in contact, insulating particles exist between a plurality of electrodes, so short-circuiting between electrodes adjacent to the horizontal direction rather than between electrodes up and down can be prevented. In addition, at the time of connection between electrodes, the conductive particle with insulating particle is pressurized by two electrodes, and the insulating particle between the conductive part of a conductive particle and an electrode can be easily excluded by this. Furthermore, in the case of the electroconductive particle which has several protrusions on the outer surface of an electroconductive part, the insulating particle between the electroconductive part of electroconductive particle and an electrode can be excluded more easily.

In the electroconductive particle with insulating particle of this invention, the particle diameter of the said insulating particle is 500 nm or more and 1500 nm or less. In the electroconductive particle with insulating particle of this invention, the said insulating particle is relatively large. Therefore, even in the case of using conductive particles with relatively large particle diameters, the insulation reliability between adjacent electrodes in the horizontal direction in the conductively connected connection structure can be further effectively improved.

The particle diameter of the said insulating particle can be suitably selected according to the particle diameter of the said electroconductive particle with insulating particle, the use, etc. of the said electroconductive particle with insulating particle. The particle size of the insulating particles is preferably more than 540 nm, more preferably 550 nm or more, more preferably 700 nm or more, especially preferably 800 nm or more, and preferably 1500 nm or less, more preferably 1200 nm or less, further preferably less than 1000 nm, further preferably 900 nm or less, and even more preferably 850 nm or less. When the particle size of the insulating particles satisfies the above-mentioned lower limit, when the conductive particles with insulating particles are dispersed in the binder resin, the conductive parts in the plurality of conductive particles with insulating particles are less likely to contact each other. If the particle size of the insulating particles satisfies the above upper limit, it is not necessary to excessively increase the pressure or heat to a high temperature in order to remove the insulating particles between the electrodes and the conductive particles during connection between electrodes. If the particle size of the insulating particles satisfies the above-mentioned lower limit and the above-mentioned upper limit, when electrically connecting between electrodes, the insulation reliability can be further effectively improved.

The particle diameter of the insulating particles is preferably an average particle diameter, more preferably a number average particle diameter. The particle diameter of the said insulating particle is calculated|required using a particle size distribution measuring apparatus etc. The particle size of the insulating particles is preferably obtained by observing arbitrary 50 insulating particles with an electron microscope or an optical microscope, calculating an average value, or performing a laser diffraction particle size distribution measurement. When measuring the particle diameter of the said insulating particle by the method of observing arbitrary 50 insulating particles among the said conductive particle with insulating particle with an electron microscope or an optical microscope, it can measure as follows, for example.

Conductive particles with insulating particles were added to and dispersed in "Technovit 4000" manufactured by Kulzer Corporation so that the content would be 30% by weight, to prepare an embedding resin for conductive particle inspection. The cross section of the conductive particles with insulating particles was cut out using an ion milling device ("IM4000" manufactured by Hitachi High-Technologies Co., Ltd.) so as to pass through the vicinity of the center of the conductive particles with insulating particles in the embedding resin for inspection. Then, using a field emission scanning electron microscope (FE-SEM), set the image magnification to 50,000 times, randomly select 50 conductive particles with insulating particles, and observe the insulating particles of each conductive particle with insulating particles. The circle-equivalent diameter of the insulating particles among the conductive particles with insulating particles was measured as the particle diameter, and the arithmetic mean was taken as the particle diameter of the insulating particles.

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

In the electroconductive particle with insulating particle of this invention, the storage elastic modulus in 60 degreeC of the said insulating particle is 100 MPa or more and 1000 MPa or less. The storage elastic modulus at 60° C. of the insulating particles is preferably at least 300 MPa, more preferably at least 500 MPa, and is preferably at most 950 MPa, more preferably at most 900 MPa. When the storage elastic modulus at 60° C. of the insulating particles is not less than the above-mentioned lower limit and not more than the above-mentioned upper limit, insulation reliability and conduction reliability can be further effectively improved when electrodes are electrically connected.

The storage elastic modulus in 60 degreeC of the said insulating particle|grains can be measured with the dynamic viscoelasticity measuring apparatus ("RSA3" by TA Instruments company). The above-mentioned measurement using the dynamic viscoelasticity measuring device uses a measurement sample with a length of 10 mm, a width of 1 mm to 10 mm, and a thickness of 15 mm to 50 mm, under the conditions of a frequency of 10 Hz, a strain of 1%, a temperature of -10°C to 210°C, and a heating rate of 5°C/min. The storage elastic modulus at 60°C was calculated from the measurement results. In addition, the said measurement sample was produced using the same raw material (material which comprises an insulating particle) as the said insulating particle.

When the storage elastic modulus at 60°C of the insulating particles is 100 MPa or more and 1000 MPa or less, the insulating particles exhibit a soft property at 60°C. If the storage elastic modulus at 60° C. of the insulating particles is within the above-mentioned preferred range, the insulating particles will exhibit very soft properties at 60° C. Also, since the temperature at the time of disposing the insulating particles on the surface of the conductive particles is about 60° C., when the insulating particles are disposed on the surface of the conductive particles, the insulating particles become very soft and can be easily disposed on the surface of the conductive particles. Moreover, since the said insulating particle can be arrange|positioned easily on the surface of the said electroconductive particle, it does not need to use coating, such as an organic compound or an inorganic oxide. Therefore, during conductive connection, the insulating particles are easily detached from the surface of the conductive particles, which can effectively improve the conduction reliability between the upper and lower electrodes to be connected.

As a method of adjusting the storage elastic modulus in 60 degreeC of the said insulating particle to 100 MPa or more and 1000 MPa or less, the following method is mentioned. A method of producing insulating particles by adjusting the glass transition temperature of a monomer. A method of producing insulating particles by mixing a main monomer with a monomer having a glass transition temperature different from that of the main monomer. A method to reduce the addition rate of the crosslinking agent relative to the main monomer. A method of using a cross-linking agent with a small functional number when making 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 from an organic compound different from both ceramics and silicon oxide. Methods other than these may also be used.

Moreover, it is preferable that the said insulating particle is obtained by polymerizing a polymeric compound from a viewpoint of making the storage elastic modulus in 60 degreeC of the said insulating particle into the said preferable range. As said polymeric compound, the material of the said resin particle etc. are mentioned. It is preferable that the side chain of the said polymeric compound is long. By making the side chain of the above-mentioned polymerizable compound longer, it is possible to obtain insulating particles exhibiting a more flexible property. Also, as described above, the insulating particles are relatively large. In order to obtain insulating particles with a large particle size, it is preferable that the side chain of the above-mentioned polymerizable compound is short. By polymerizing a polymerizable compound with a short side chain, insulating particles with a large particle size can be easily obtained, but it is difficult for insulating particles obtained from a polymerizable compound with a short side chain to exhibit soft properties. Therefore, as a method of imparting soft properties to insulating particles obtained from a polymerizable compound with a short side chain, a method of introducing a reactive functional group that does not participate in the polymerization of the polymerizable compound and has reactivity with epoxy groups and the like to a polymerizable compound with a short side chain, etc. By introducing the above-mentioned reactive functional group into a polymerizable compound with a short side chain, after the polymerizable compound with a short side chain is polymerized to obtain insulating particles, the above-mentioned reactive functional group is reacted with a compound with a long chain length, thereby imparting soft properties to the insulating particles. As a result, insulating particles can be easily arranged on the surface of the above-mentioned conductive particles.

The swelling ratio of the insulating particles is preferably at least 1, more preferably at least 1.2, and is preferably at most 2.5, more preferably at most 2. The said insulating particle can be arrange|positioned more easily on the surface of the said electroconductive particle that the said swelling ratio is more than the said minimum. When the said swelling ratio is below the said upper limit, when electrically connecting between electrodes, insulation reliability and conduction reliability can be improved more effectively.

The above swelling ratio is an indicator of the flexibility of insulating particles. The higher the swelling ratio, the softer the insulating particles are.

The above swelling ratio can be measured as follows.

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

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

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

The ratio of the number of insulating particles 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, it is preferably obtained by observing conductive particles with insulating particles from one direction with a scanning electron microscope (SEM), counting the number of insulating particles in each conductive particle with insulating particles, and the number of insulating particles that are not in contact with other insulating particles, and calculating the average value.

As a material which comprises the said insulating particle, an insulating resin etc. are mentioned. As said insulating resin, the material etc. which can be used as the resin particle of a base material particle are mentioned.

Specific examples of the insulating resin as a material of the insulating particles include polyolefin compounds, (meth)acrylate polymers, (meth)acrylate copolymers, block polymers, thermoplastic resins, cross-linked thermoplastic resins, thermosetting resins, and water-soluble resins.

As said polyolefin compound, polyethylene, an ethylene-vinyl acetate copolymer, an ethylene-acrylate copolymer, etc. are mentioned. As said (meth)acrylate polymer, polymethyl (meth)acrylate, polyethyl (meth)acrylate, polybutyl (meth)acrylate, etc. are mentioned. Examples of the block polymer include polystyrene, styrene-acrylate copolymers, SB-type styrene-butadiene block copolymers, SBS-type styrene-butadiene block copolymers, and hydrogenated products thereof. As said thermoplastic resin, a vinyl polymer, a vinyl copolymer, etc. are mentioned. As said thermosetting resin, an epoxy resin, a phenol resin, a melamine resin, etc. are mentioned. Examples of the water-soluble resin include polyvinyl alcohol, polyacrylic acid, polyacrylamide, polyvinylpyrrolidone, polyethylene oxide, and methylcellulose.

When adjusting the storage modulus of elasticity at 60° C. of insulating particles with a crosslinking agent, it is preferable that the material constituting the insulating particles include a crosslinking agent. From the viewpoint of adjusting the storage elastic modulus at 60° C. to 100 MPa or more and 1000 MPa or less, the above-mentioned crosslinking agent is preferably a bifunctional to hexafunctional crosslinking agent. The bifunctional to hexafunctional crosslinking agent is preferably a bifunctional to hexafunctional (meth)acrylate monomer, more preferably a bifunctional to tetrafunctional (meth)acrylate monomer, and even more preferably a bifunctional (meth)acrylate monomer. As a monomer of the bifunctional to hexafunctional (meth)acrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate or ethylene glycol dimethacrylate are preferable, and ethylene glycol dimethacrylate is more preferable.

The content of the crosslinking agent is preferably at least 0.001 parts by weight, more preferably at least 0.01 parts by weight, and still more preferably at least 0.1 parts by weight, from the viewpoint of easily adjusting the storage modulus of elasticity at 60°C of the insulating particles to 100 MPa to 1000 MPa. The content of the crosslinking agent is preferably 20 parts by weight or less, more preferably 10 parts by weight or less, and still more preferably 6 parts by weight or less, with respect to 100 parts by weight of the most abundant material among the materials constituting the insulating particles, from the viewpoint of easily adjusting the storage elastic modulus at 60°C of the insulating particles to 100 MPa or more and 1000 MPa or less.

As a method of arranging the said insulating particle on the surface of the said electroconductive part, a chemical method, and a physical or mechanical method etc. are mentioned. As said chemical method, the interfacial polymerization method, the suspension polymerization method in particle presence, the emulsion polymerization method etc. are mentioned, for example. Examples of the above-mentioned physical or mechanical methods include spray drying, hybridization, electrostatic adhesion, spraying, immersion, and methods using vacuum evaporation. The method of arranging the insulating particles on the surface of the conductive portion is preferably a physical method from the viewpoint of further effectively improving insulation reliability and conduction reliability when electrically connecting electrodes.

The outer surface of the conductive part and the outer surface of the insulating particle may be respectively coated with a compound having a reactive functional group. The outer surface of the conductive portion and the outer surface of the insulating particle may not be chemically bonded directly, but may be chemically bonded indirectly via a compound having a reactive functional group. After carboxyl groups are introduced into the outer surface of the above-mentioned conductive part, the carboxyl groups may be chemically bonded to the functional groups on the outer surface of the insulating particles via a polymer electrolyte such as polyethyleneimine.

In the electroconductive particle with insulating particle of this invention, the insulating particle of 2 or more types from which a particle diameter differs can also be used together. By using together two or more types of insulating particles with different particle diameters, the insulating particles with smaller particle diameters can enter the gaps covered with the insulating particles with larger particle diameters, and the above-mentioned coverage can be further effectively increased.

The coefficient of variation (CV value) of the particle diameter of the insulating particles is preferably 20% or less. If the coefficient of variation of the particle diameter of the above-mentioned insulating particles is below the above-mentioned upper limit, the thickness of the portion covered by the insulating particles of the obtained conductive particles with insulating particles becomes more uniform, and it is easier to apply pressure uniformly during conductive connection, and the connection resistance between electrodes can be further reduced.

The said 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 particle size of insulating particles

The shape of the above-mentioned insulating particles is not particularly limited. The shape of the above-mentioned insulating particles may be spherical, may be other than spherical, or may be flat or the like.

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

The above-mentioned binder resin is not particularly limited. As the binder resin, known insulating resins can be used. The above-mentioned binder resin preferably contains a thermoplastic component (thermoplastic compound) or a curable component, and more preferably contains a curable component. As said curable component, a photocurable component and a thermosetting component are mentioned. It is preferable that the said photocurable component contains a photocurable compound and a photoinitiator. The above-mentioned thermosetting component preferably contains a thermosetting compound and a thermosetting agent.

As said binder resin, a vinyl resin, a thermoplastic resin, curable resin, a thermoplastic block copolymer, an elastomer, etc. are mentioned, for example. The said binder resin may use only 1 type, and may use 2 or more types together.

As said vinyl resin, a vinyl acetate resin, an acrylic resin, a styrene resin, etc. are mentioned, for example. As said thermoplastic resin, a polyolefin resin, an ethylene-vinyl acetate copolymer, a polyamide resin, etc. are mentioned, for example. Examples of the curable resin include epoxy resins, urethane resins, polyimide resins, and unsaturated polyester resins. Furthermore, the above curable resin may also be a room temperature curable resin, a thermosetting resin, a photocurable resin or a moisture curable resin. The above curable resins may also be used in combination with a curing agent. Examples of the thermoplastic block copolymer include styrene-butadiene-styrene block copolymers, styrene-isoprene-styrene block copolymers, hydrogenated styrene-butadiene-styrene block copolymers, and hydrogenated styrene-isoprene-styrene block copolymers. As said elastomer, a styrene-butadiene copolymer rubber, an acrylonitrile-styrene block copolymer rubber, etc. are mentioned, for example.

In addition to the above-mentioned conductive particles with insulating particles and the above-mentioned binder resin, various additives such as fillers, extenders, softeners, plasticizers, polymerization catalysts, hardening catalysts, colorants, antioxidants, heat stabilizers, light stabilizers, ultraviolet absorbers, lubricants, antistatic agents, and flame retardants may also be included in the above-mentioned conductive material.

As a method for dispersing the conductive particles with insulating particles in the binder resin, a conventionally known dispersion method can be used, and it is not particularly limited. As a method of dispersing the electroconductive particle with the said insulating particle in the said binder resin, the following method etc. are mentioned, for example. A method in which the above-mentioned conductive particles with insulating particles are added to the above-mentioned binder resin, and then kneaded by a planetary mixer or the like to disperse them. A method in which the above-mentioned conductive particles with insulating particles are uniformly dispersed in water or an organic solvent using a homogenizer, etc., then added to the above-mentioned binder resin, and kneaded by a planetary mixer to disperse them. A method in which the above-mentioned binder resin is diluted with water or an organic solvent, then the above-mentioned conductive particles with insulating particles are added, and kneaded by a planetary mixer to disperse them.

The viscosity (η25) at 25°C of the conductive material is preferably at least 30 Pa·s, more preferably at least 50 Pa·s, and is preferably at most 400 Pa·s, more preferably at most 300 Pa·s. If the viscosity at 25° C. of the above-mentioned conductive material is more than the above-mentioned lower limit and below the above-mentioned upper limit, the insulation reliability between electrodes can be further effectively improved, and the conduction reliability between electrodes can be further effectively improved. The above-mentioned viscosity (η25) can be appropriately adjusted by the type and amount of the compounded ingredients.

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

The conductive material of the present invention can be used as a conductive paste, a conductive film, and the like. When the conductive material of the present invention is a conductive film, a film not containing conductive particles may be laminated on a conductive film containing conductive particles. The above-mentioned conductive paste is preferably anisotropic conductive paste. The above-mentioned conductive film is preferably an anisotropic conductive film.

In 100% by weight of the conductive material, the content of the binder resin is preferably at least 10% by weight, more preferably at least 30% by weight, further preferably at least 50% by weight, especially preferably at least 70% by weight, and is preferably at most 99.99% by weight, more preferably at most 99.9% by weight. When content of the said binder resin is more than the said minimum and below the said upper limit, electroconductive particle can be efficiently arrange|positioned between electrodes, and the connection reliability of the connection object member connected by a conductive material can be further improved.

In 100% by weight of the conductive material, the content of the conductive particles with insulating particles is preferably at least 0.01% by weight, more preferably at least 0.1% by weight, and is preferably at most 80% by weight, more preferably at most 60% by weight, further preferably at most 40% by weight, especially preferably at most 20% by weight, and most preferably at most 10% by weight. The conduction reliability and insulation reliability between electrodes can be further improved that content of the said electroconductive particle with insulating particle is more than the said minimum and below the said upper limit.

(connection structure) The connection structure of the present invention includes: a first connection object member having a first electrode on its surface, a second connection object member having a second electrode on its surface, and a connection portion connecting the first connection object member and the second connection object member. In the connection structure of this invention, the material of the said connection part is the said conductive particle with insulating particle, or is the conductive material containing the said conductive particle with insulating particle and binder resin. In the connection structure of this invention, the said 1st electrode and the said 2nd electrode are electrically connected by the said electroconductive part in the said electroconductive particle with insulating particle.

The connection structure can be obtained through the steps of arranging the conductive particles with insulating particles or the conductive material between the first member to be connected and the second member to be connected, and performing conductive connection by thermocompression bonding. It is preferable that the insulating particles are detached from the conductive particles with insulating particles during the thermocompression bonding.

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 equipped with the 1st connection object member 82, the 2nd connection object member 83, and the connection part 84 which connects the 1st connection object member 82 and the 2nd connection object member 83. The connection portion 84 is formed of a conductive material including the conductive particles 1 with insulating particles. The connection part 84 is preferably formed by hardening the conductive material including the conductive particles 1 with insulating particles. In addition, in FIG. 4, for convenience of illustration, the electroconductive particle 1 with insulating particle is shown schematically. In addition to the electroconductive particle 1 with an insulating particle, the electroconductive particle 21 or 41 with an insulating particle can also be used.

The first connection object member 82 has a plurality of first electrodes 82a on the surface (upper surface). The 2nd connection object member 83 has the some 2nd electrode 83a on the surface (lower surface). The 1st electrode 82a and the 2nd electrode 83a are electrically connected by the electroconductive particle 2 in the electroconductive particle 1 with one or plural insulating particles. Therefore, the 1st connection object member 82 and the 2nd connection object member 83 are electrically connected by the electroconductive part in the electroconductive particle 1 with insulating particle.

The manufacturing method of the said connection structure is not specifically limited. As an example of the method of manufacturing the connection structure, a method of arranging the above-mentioned conductive material between the first member to be connected and the second member to be connected to obtain a laminate, and then heating and pressurizing the laminate can be mentioned. The pressure of the thermocompression bonding is preferably at least 40 MPa, more preferably at least 60 MPa, and is preferably at most 90 MPa, more preferably at most 70 MPa. The heating temperature for the thermocompression bonding is preferably 80°C or higher, more preferably 100°C or higher, and preferably 140°C or lower, more preferably 120°C or lower. If the pressure and temperature of the thermocompression bonding are above the above-mentioned lower limit and below the above-mentioned upper limit, the insulating particles can be easily detached from the surface of the conductive particles with insulating particles during conductive connection, and the conduction reliability between electrodes can be further improved.

When heating and pressurizing the said laminated body, the said insulating particle which exists between the said electroconductive particle, the said 1st electrode, and the said 2nd electrode can be excluded. For example, during the heating and pressurization, the insulating particles present between the conductive particles, the first electrode, and the second electrode are easily detached from the surface of the conductive particle with insulating particles. In addition, at the time of the said heating and pressurization, a part of the said insulating particle|grains may detach from the surface of the said electroconductive particle with insulating particle|grains, and the surface part of the said electroconductive part may be exposed. The exposed portion of the surface of the conductive portion is in contact with the first electrode and the second electrode, whereby the first electrode and the second electrode can be electrically connected via the conductive particles.

The said 1st connection object member and the 2nd connection object member are not specifically limited. Specific examples of the first connection object member and the second connection object member include electronic components such as semiconductor wafers, semiconductor packages, LED (light-emitting diode) chips, LED packages, capacitors, and diodes, and electronic components such as circuit boards such as resin films, printed circuit boards, flexible printed circuit boards, flexible flat cables, rigid flexible substrates, glass epoxy substrates, and glass substrates. It is preferable that the said 1st connection object member and the 2nd connection object member are electronic components.

Examples of electrodes provided on the member to be connected 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 circuit board, the electrode is preferably a gold electrode, a nickel electrode, a tin electrode, a silver electrode or a copper electrode. When the member to be connected is a glass substrate, the electrode is preferably an aluminum electrode, a copper electrode, a molybdenum electrode, a silver electrode, or a tungsten electrode. Furthermore, when the above-mentioned electrode is an aluminum electrode, it may be an electrode formed only of aluminum, or an electrode formed by laminating an aluminum layer on the surface of a metal oxide layer. Examples of the material for the metal oxide layer include indium oxide doped with a trivalent metal element, zinc oxide doped with a trivalent metal element, and the like. Sn, Al, Ga, etc. are mentioned as said trivalent metal element.

Hereinafter, an Example and a comparative example are given, and this invention is demonstrated concretely. The present invention is not limited to the following examples.

(Example 1) (1) Production of conductive particles Resin particles (particle diameter: 20 μm) formed by copolymerizing tetramethylolmethane tetraacrylate and divinylbenzene were prepared. Using an ultrasonic disperser, 10 parts by weight of the substrate particles were dispersed in 100 parts by weight of an alkali solution containing 5% by weight of a palladium catalyst solution, and the solution was filtered to take out the substrate particles. Next, the substrate particles were added to 100 parts by weight of a 1% by weight solution of dimethylamine borane to activate the surface of the substrate particles. After sufficiently washing the surface-activated substrate particles with water, they were added to 500 parts by weight of distilled water and dispersed to obtain a dispersion. Next, 1 g of nickel particle slurry (average particle diameter: 100 nm) was added to the dispersion liquid over 3 minutes to obtain a suspension containing substrate particles to which the core substance was attached.

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

While stirring the resulting suspension at 70°C, the above nickel plating solution was slowly added dropwise to the suspension to perform electroless nickel plating. Thereafter, the particles were taken out by filtering the suspension, washed with water, and dried to obtain particles in which the first conductive portion (nickel-boron layer, thickness 200 nm) was formed on the surface of the substrate particle.

A suspension was obtained by adding and dispersing 10 parts by weight of particles on which the first conductive portion was formed to 100 parts by weight of distilled water. Also, 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 resulting suspension at 70° C., the reduction gold plating solution was slowly added dropwise to the suspension to perform reduction gold plating. Thereafter, the particles were taken out by filtering the suspension, washed with water, and dried to obtain conductive particles. In the obtained electroconductive particle, the 2nd electroconductive part (gold layer, thickness 35 nm) was formed in the outer surface of the said 1st electroconductive part.

(2) Production of insulating particles After adding the following composition to 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, distilled water was added to the above composition so that the solid content became 10% by weight, stirred at 120 rpm, and polymerized at 50° C. for 5 hours under a nitrogen atmosphere. The above-mentioned composition contained 1080 mmol of methyl methacrylate, 10 mmol of ethylene glycol dimethacrylate (crosslinking agent), 0.5 mmol of 4-(methacryloxy)phenyldimethyl perulium methosulfate, and 0.5 mmol of 2,2'-azobis{2-[N-(2-carboxyethyl)amidino]propane}. After the reaction was completed, freeze-drying was carried out to obtain insulating particles (particle diameter: 540 nm) having a pyl group derived from 4-(methacryloyloxy)phenyldimethylconium methosulfate on the surface.

(3) Production of conductive particles with insulating particles The insulating particles obtained above were dispersed in distilled water under ultrasonic irradiation to obtain a 10% by weight 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% by weight aqueous dispersion of insulating particles was added, and stirred at room temperature for 8 hours. After filtering with a 3 μm mesh filter, it was washed with methanol and dried to obtain conductive particles with insulating particles.

(4) Production of conductive materials (anisotropic conductive paste) 7 parts by weight of the conductive particles obtained, 25 parts by weight of bisphenol A-type phenoxy resin, 4 parts by weight of fennel-type epoxy resin, 30 parts by weight of phenol novolac-type epoxy resin, and SI-60L (manufactured by Sanshin Chemical Industry Co., Ltd.) were prepared, defoamed and stirred for 3 minutes, thereby obtaining a conductive material (anisotropic conductive paste).

(5) Fabrication of connection structures A transparent glass substrate with an IZO electrode pattern (1st electrode, Vickers hardness of the metal on the electrode surface: 100 Hv) formed on the upper surface with an L/S of 10 μm/10 μm was prepared. Also, a semiconductor wafer was prepared in which an Au electrode pattern (second electrode, Vickers hardness of the metal on the electrode surface: 50 Hv) was formed on the lower surface with an L/S of 10 μm/10 μm.

The obtained anisotropic conductive paste was applied on the above-mentioned transparent glass substrate so as to have a thickness of 30 μm to form an anisotropic conductive paste layer. Next, the above-mentioned semiconductor wafer was laminated on the anisotropic conductive paste layer so that the electrodes faced each other. Thereafter, while adjusting the temperature of the head so that the temperature of the anisotropic conductive paste layer becomes 100°C, a pressure heating head was placed on the upper surface of the semiconductor wafer, and a pressure of 60 MPa was applied to harden the anisotropic conductive paste layer at 100°C to obtain a connection structure.

(Example 2) When preparing insulating particles, the amount of methyl methacrylate in the above composition was changed from 1080 mmol to 540 mmol, and 540 mmol of glycidyl methacrylate was added to the above composition. In addition, the particle size of the insulating particles was changed to 750 nm when producing the insulating particles. Except for the said change, it carried out similarly to Example 1, and obtained the electroconductive particle, the electroconductive particle with insulating particle, a conductive material, and a connection structure.

(Example 3) When preparing insulating particles, the amount of methyl methacrylate in the above composition was changed from 1080 mmol to 540 mmol, and 540 mmol of glycidyl methacrylate was added to the above composition. In addition, the particle size of the insulating particles was changed to 800 nm during production of the insulating particles. Except for the said change, it carried out similarly to Example 1, and obtained the electroconductive particle, the electroconductive particle with insulating particle, a conductive material, and a connection structure.

(Example 4) When preparing insulating particles, the amount of methyl methacrylate in the above composition was changed from 1080 mmol to 540 mmol, and 540 mmol of glycidyl methacrylate was added to the above composition. Moreover, the particle diameter of the insulating particle was changed to 1400 nm at the time of preparation of the insulating particle. Except the above-mentioned change, it carried out similarly to Example 1, and obtained the electroconductive particle, the electroconductive particle with insulating particle, a conductive material, and a connection structure.

(Example 5) When making conductive particles, the thickness of the first conductive part (nickel-boron layer) was changed to 250 nm, and the second conductive part (gold layer, thickness 35 nm) was not formed. Except for this, conductive particles, conductive particles with insulating particles, conductive materials, and connection structures were obtained in the same manner as in Example 3.

(Example 6) Conductive particles, conductive particles with insulating particles, conductive material, and connection structure were obtained in the same manner as in Example 3 except that the nickel particle slurry (average particle diameter: 100 nm) was not used in the production of conductive particles.

(Example 7) In the production of conductive particles, except that nickel particle slurry (average particle diameter 250 nm) was used instead of nickel particle slurry (average particle diameter 100 nm), conductive particles, conductive particles with insulating particles, conductive materials, and connection structures were obtained in the same manner as in Example 3.

(Embodiment 8) In the production of conductive particles, except that nickel particle slurry (average particle diameter 450 nm) was used instead of nickel particle slurry (average particle diameter 100 nm), conductive particles, conductive particles with insulating particles, conductive materials, and connection structures were obtained in the same manner as in Example 3.

(Example 9) In the production of conductive particles, resin particles (particle diameter: 3 μm) formed by copolymerizing resin of tetramethylolmethane tetraacrylate and divinylbenzene were used instead of resin particles (particle diameter: 20 μm) formed by copolymerizing resin of tetramethylolmethane tetraacrylate and divinylbenzene. Except for the said change, it carried out similarly to Example 3, and obtained the electroconductive particle, the electroconductive particle with insulating particle, a conductive material, and a connection structure.

(Example 10) When producing conductive particles, the thickness of the first conductive part (nickel-boron layer) was changed to 250 nm, and the second conductive part (gold layer, thickness 35 nm) was not formed. In addition, when producing conductive particles, resin particles (particle diameter: 3 μm) formed by copolymerizing resin of tetramethylolmethane tetraacrylate and divinylbenzene were used instead of resin particles (particle diameter: 20 μm) formed by copolymerizing resin of tetramethylolmethane tetraacrylate and divinylbenzene. Except for the said change, it carried out similarly to Example 3, and obtained the electroconductive particle, the electroconductive particle with insulating particle, a conductive material, and a connection structure.

(Example 11) In the production of conductive particles, resin particles (particle diameter: 10 μm) formed by copolymerizing resin of tetramethylolmethane tetraacrylate and divinylbenzene were used instead of resin particles (particle diameter: 20 μm) formed by copolymerizing resin of tetramethylolmethane tetraacrylate and divinylbenzene. Except for the said change, it carried out similarly to Example 3, and obtained the electroconductive particle, the electroconductive particle with insulating particle, a conductive material, and a connection structure.

(Example 12) In the production of conductive particles, resin particles (particle diameter: 35 μm) formed by copolymerizing resin of tetramethylolmethane tetraacrylate and divinylbenzene were used instead of resin particles (particle diameter: 20 μm) formed by copolymerizing resin of tetramethylolmethane tetraacrylate and divinylbenzene. Except for the said change, it carried out similarly to Example 3, and obtained the electroconductive particle, the electroconductive particle with insulating particle, a conductive material, and a connection structure.

(Example 13) In the production of conductive particles, resin particles (particle diameter: 50 μm) formed by copolymerizing resin of tetramethylolmethane tetraacrylate and divinylbenzene were used instead of resin particles (particle diameter: 20 μm) formed by copolymerizing resin of tetramethylolmethane tetraacrylate and divinylbenzene. Except for the said change, it carried out similarly to Example 3, and obtained the electroconductive particle, the electroconductive particle with insulating particle, a conductive material, and a connection structure.

(Example 14) In the preparation of insulating particles, except that the compounding amount of methyl methacrylate in the above composition was changed from 1080 mmol to 80 mmol, and 1000 mmol of glycidyl methacrylate was added to the above composition, conductive particles, conductive particles with insulating particles, conductive materials, and connection structures were obtained in the same manner as in Example 3.

(Example 15) In the preparation of insulating particles, the amount of methyl methacrylate in the above composition was changed from 1080 mmol to 680 mmol, and 400 mmol of glycidyl methacrylate was added to the above composition. Conductive particles, conductive particles with insulating particles, conductive materials, and connection structures were obtained in the same manner as in Example 3.

(Example 16) In the preparation of insulating particles, except that the blending amount of ethylene glycol dimethacrylate in the above composition was changed from 10 mmol to 15 mmol, conductive particles, conductive particles with insulating particles, conductive materials, and connection structures were obtained in the same manner as in Example 3.

(Example 17) In the preparation of insulating particles, except that the blending amount of ethylene glycol dimethacrylate in the above composition was changed from 10 mmol to 20 mmol, conductive particles, conductive particles with insulating particles, conductive materials, and connection structures were obtained in the same manner as in Example 3.

(comparative example 1) In the preparation of the insulating particles, except that the particle diameter of the insulating particles was changed to 450 nm, the conductive particles, the conductive particles with insulating particles, the conductive material, and the connection structure were obtained in the same manner as in Example 1.

(comparative example 2) In the preparation of the insulating particles, except that the particle diameter of the insulating particles was changed to 450 nm, it was carried out in the same manner as in Example 3 to obtain conductive particles, conductive particles with insulating particles, a conductive material, and a connection structure.

(comparative example 3) In the preparation of the insulating particles, except that the particle diameter of the insulating particles was changed to 360 nm, it was carried out in the same manner as in Example 3 to obtain conductive particles, conductive particles with insulating particles, a conductive material, and a connection structure.

(comparative example 4) When preparing insulating particles, the amount of methyl methacrylate in the above composition was changed from 1080 mmol to 540 mmol, and 540 mmol of glycidyl methacrylate was added to the above composition. In addition, the particle size of the insulating particles was changed to 2500 nm when producing the insulating particles. Except for the said change, it carried out similarly to Example 1, and obtained the electroconductive particle, the electroconductive particle with insulating particle, a conductive material, and a connection structure.

(comparative example 5) In the preparation of insulating particles, 100 mmol of dipentaerythritol hexaacrylate was added to the above composition. In addition, the particle size of the insulating particles was changed to 800 nm when producing the insulating particles. Except the above-mentioned change, it carried out similarly to Example 1, and obtained the electroconductive particle, the electroconductive particle with insulating particle, a conductive material, and a connection structure.

(comparative example 6) In preparation of insulating particles, 1080 mmol of 2-ethylhexyl methacrylate was added to the above composition instead of 1080 mmol of methyl methacrylate. In addition, the particle size of the insulating particles was changed to 800 nm when producing the insulating particles. Except the above-mentioned change, it carried out similarly to Example 1, and obtained the electroconductive particle, the electroconductive particle with insulating particle, a conductive material, and a connection structure.

(evaluate) (1) Particle size of insulating particles Arbitrary 50 insulating particles were observed with an electron microscope, and the average value was calculated to determine the particle diameter of the obtained insulating particles.

(2) Storage elastic modulus of insulating particles at 60°C Using the same raw material (material constituting the insulating particles) as the obtained insulating particles, a measurement sample with a length of 10 mm, a width of 1 mm to 10 mm, and a thickness of 15 mm to 50 mm was produced. Using a dynamic viscoelasticity measuring device ("RSA3" manufactured by TA Instruments Co., Ltd.), the storage modulus of elasticity at 60°C of the above-mentioned measurement sample was measured under the conditions of a frequency of 10 Hz, a strain of 1%, a temperature of -10°C to 210°C, and a heating rate of 5°C/min. The storage elastic modulus at 60°C was calculated from the measurement results.

In addition, the measurement sample was produced as follows. Prepare a polysiloxane rubber of 30 mm x 40 mm, which is hollowed out in the center into the shape of the measurement sample (length 10 mm, width 1 mm-10 mm, thickness 15 mm-50 mm). The polysiloxane rubber was placed on a glass slice of 30 mm×40 mm. The same raw material as that of the insulating particles (the material constituting the insulating particles) was poured into the hollowed out portion of the silicone rubber on the glass slice. A 30mm×40mm glass slice was placed on the polysiloxane rubber in which the same raw material as the insulating particles had flowed in, and fixed with a jig to obtain a laminate. The obtained laminate was put into an oven, and reacted at 50° C. for 5 hours under a nitrogen atmosphere. After the reaction, the jig was removed, and the measurement sample was taken out.

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

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

(4) Ratio X of the number of insulating particles arranged on the surface of the conductive particles without contacting other insulating particles in the total number of insulating particles The obtained conductive particles with insulating particles were observed with a scanning electron microscope (SEM), and the number of insulating particles among the 20 conductive particles with insulating particles and the number of insulating particles that were not in contact with other insulating particles were calculated. Based on the obtained results, the ratio X of the number of insulating particles arranged on the surface of the conductive particles in a manner not to contact with other insulating particles in the total number of insulating particles was calculated as the average value of 20 conductive particles with insulating particles. The ratio X of the above-mentioned numbers was determined on the basis of the following.

[Criteria for judging the ratio X of the number of insulating particles arranged on the surface of conductive particles without contacting other insulating particles in the total number of insulating particles] AA: The ratio X of the number is more than 50% A: The ratio X of the number is more than 30% and less than 50% B: The ratio X of the number is more than 10% and less than 30% C: The ratio X of the number is less than 10%

(5) Particle size of conductive particles The particle diameter of the obtained electroconductive particle was measured using the "laser diffraction type particle size distribution measuring apparatus" manufactured by Horiba Seisakusho. Moreover, the particle diameter of electroconductive particle calculated by averaging the measurement result of 20 times.

Moreover, the ratio of the particle diameter of electroconductive particle with respect to the particle diameter of insulating particle was calculated from the measurement result of the particle diameter of insulating particle and the particle diameter of electroconductive particle.

(6) Conduction reliability (between the upper and lower electrodes) The connection resistances between the upper and lower electrodes of the obtained 20 connection structures were measured by the 4-terminal method. Furthermore, according to the relationship of voltage=current×resistance, the connection resistance can be obtained by measuring the voltage when a certain current is passed through. Conduction reliability was judged according to the following criteria.

[Criteria for judging conduction reliability] ○○○: The connection resistance is 2.0 Ω or less ○○: The connection resistance exceeds 2.0 Ω and is 5.0 Ω or less ○: The connection resistance exceeds 5.0 Ω and is 10 Ω or less ×: Connection resistance exceeds 10 Ω

(7) Insulation reliability (between electrodes adjacent in the horizontal direction) Among 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. The insulation reliability was evaluated according to the following criteria.

[Criteria for judging insulation reliability] ○○○: The number of connection structures with a resistance value of 10 ⁸ Ω or more is 18 or more ○○: The number of connection structures with a resistance value of 10 ⁸ Ω or more is 15 or more and less than 18 ○: The number of connection structures with a resistance value of 10 ⁸ Ω or more is 10 or more and less than 15 ×: The number of connection structures with a resistance value of 10 ⁸ Ω or more is less than 10

The results are shown in Tables 1 to 3 below.

[Table 1]

[Table 2]

[table 3]

1: Conductive particles with insulating particles 2: Conductive particles 3: insulating particles 11: Substrate particles 12: Conductive part 21: Conductive particles with insulating particles 22: Conductive particles 31: Conductive part 32: core substance 33:Protrusion 41: Conductive particles with insulating particles 42: Conductive particles 51: Conductive part 52: Protrusion 81: Connection Construct 82: The first connection object member 82a: 1st electrode 83: The second connection target member 83a: 2nd electrode 84: connection part

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.

Claims (8)

A conductive particle with insulating particles, comprising: 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, and the particle diameter of the insulating particles is 500nm to 1500nm, and the storage modulus of elasticity at 60°C of the insulating particles is 100MPa to 1000MPa. The conductive particle with insulating particles according to claim 1, wherein the conductive particle has protrusions on the outer surface of the conductive part. The conductive particles 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. Conductive particles with insulating particles as claimed in claim 1 or 2, wherein the swelling ratio of the insulating particles calculated by the following formula (1) is 1 to 2.5, swelling ratio = [the weight of the measurement sample after toluene immersion (g) / the weight of the measurement sample before toluene immersion (g)]‧‧‧‧Equation (1) The weight of the measurement sample before toluene immersion (g): use the same raw material as the above insulating particles to make 10mm x 5mm, thickness 0 .5mm weight of the measurement sample Weight of the measurement sample after dipping in toluene (g): The above measurement sample was immersed in 100g of toluene at 25°C for 20 hours, then the measurement sample was taken out and dried at 160°C for 30 minutes. weight. The conductive particles with insulating particles according to claim 1 or 2, wherein more than 10% of the total number of the insulating particles are arranged on the surface of the conductive particles so as not to be in contact with other insulating particles. The conductive particles with insulating particles according to claim 1 or 2, wherein the particle diameter of the above-mentioned conductive particles is not less than 1 μm and not more than 50 μm. A conductive material comprising conductive particles with insulating particles according to any one of claims 1 to 6, and a binder resin. A connection structure comprising: a first connection object member having a first electrode on its surface, a second connection object member having a second electrode on its surface, and a connection portion connecting the first connection object member to the second connection object member, and the material of the connection portion is conductive particles with insulating particles according to any one of claims 1 to 6, or a conductive material including the conductive particles with insulating particles and a binder resin, and the first electrode and the second electrode are connected by the conductive particles with insulating particles The above-mentioned conductive parts are electrically connected.