TW202044283A - Conductive particles, conductive material, and connection structure - Google Patents

Abstract

Provided are conductive particles with which it is possible to effectively reduce the connection resistance between electrodes and to effectively prevent the conductive particles from aggregating together. The conductive particles each comprise a base particle and a conductive portion disposed on the surface of the base particle, wherein the base particle contains a conductive metal inside the base particle.

Description

Conductive particles, conductive materials, and connection structures

The present invention relates to a conductive particle in which a conductive part is arranged on the surface of a substrate particle. In addition, the present invention relates to a conductive material and a connection structure using the above-mentioned conductive particles.

Anisotropic conductive materials such as anisotropic conductive paste and anisotropic conductive film are widely known. In this anisotropic conductive material, conductive particles are dispersed in a binder resin. Moreover, as electroconductive particle, the electroconductive particle which has a base particle and the electroconductive part arrange|positioned on the surface of this base particle may be used.

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

As an example of the above-mentioned conductive particle, the following patent document 1 discloses a conductive particle provided with a nickel layer and a gold layer formed on this nickel layer. The average film thickness of the above-mentioned gold layer is less than 300 Å. In this conductive particle, the above-mentioned gold layer is the outermost layer. In addition, in the conductive particles, the elemental composition ratio (Ni/Au) of nickel and gold on the surface of the conductive particles obtained by X-ray photoelectron spectroscopy analysis is 0.4 or less.

The following Patent Document 2 discloses a conductive particle provided with core particles, a Ni plating layer, a precious metal plating layer, and a rust preventive film. The Ni plating layer coats the core particles. The noble metal plating layer coats at least a part of the Ni plating layer. The noble metal plating layer includes at least any one of Au and Pd. The anticorrosive film coats at least any one of the Ni plating layer and the noble metal plating layer. The above-mentioned anti-rust film contains an organic compound. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2009-102731 [Patent Document 2] Japanese Patent Laid-Open No. 2013-20721

[The problem to be solved by the invention]

In recent years, in conductive materials containing conductive particles, the particle size of conductive particles has been reduced by the fine pitch of wiring and connectors in printed wiring boards and the like.

In order to sufficiently reduce the connection resistance between the electrodes in the vertical direction when manufacturing a connection structure by using conductive particles with a small particle diameter to connect the electrodes, the thickness of the conductive part in the conductive particles may be increased. However, if the thickness of the conductive part is increased, when the conductive part is formed by plating, the conductive particles may aggregate. When agglomeration of conductive particles occurs, the electrodes adjacent to each other in the lateral direction are often easily connected, and it may be difficult to improve the insulation reliability between the electrodes adjacent in the lateral direction.

In addition, if the thickness of the conductive part is made thin to suppress the aggregation of conductive particles, when the conductive part is formed by plating, although the aggregation of the conductive particles can be suppressed, it is difficult to sufficiently reduce the connection between the electrodes in the vertical direction resistance. In the conventional conductive particles, it is difficult to balance the reduction of the connection resistance between the electrodes and the suppression of the aggregation of the conductive particles.

The object of the present invention is to provide conductive particles that can effectively reduce the connection resistance between electrodes and can effectively suppress the occurrence of aggregation of conductive particles. In addition, an object of the present invention is to provide a conductive material and a connection structure using the above-mentioned conductive particles. [Technical means to solve the problem]

According to a broad aspect of the present invention, there is provided a conductive particle including a substrate particle and a conductive portion arranged on the surface of the substrate particle, the substrate particle containing a conductive metal inside the substrate particle .

In a specific aspect of the conductive particles of the present invention, the porosity of the substrate particles is 10% or more.

In a specific aspect of the conductive particles of the present invention, the conductive metal includes nickel, gold, palladium, silver, or copper.

In a specific aspect of the conductive particle of the present invention, the conductive portion includes nickel, gold, palladium, silver, or copper.

In a specific aspect of the conductive particles of the present invention, the 10% K value of the conductive particles is 100 N/mm ² or more and 25000 N/mm ² or less.

In a specific aspect of the conductive particle of the present invention, the 30% K value of the conductive particle is 100 N/mm ² or more and 15000 N/mm ² or less.

In a specific aspect of the conductive particles of the present invention, the ratio of the 10% K value of the conductive particles to the 30% K value of the conductive particles is 1.5 or more and 5 or less.

In a specific aspect of the conductive particle of the present invention, the particle size of the conductive particle is 0.1 μm or more and 1000 μm or less.

In a specific aspect of the conductive particles of the present invention, in 100% by volume of the conductive particles, the content of the conductive metal contained in the base particles is from 0.1% by volume to 30% by volume.

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

In a specific aspect of the conductive particle of the present invention, the conductive particle includes an insulating substance arranged on the outer surface of the conductive part.

According to a broad aspect of the present invention, a conductive material is provided, which includes the above-mentioned conductive particles and a binder resin.

In a specific aspect of the conductive material of the present invention, the conductive material includes a plurality of the conductive particles, and the distance from the outer surface of the substrate particle toward the center is 1/2 of the particle diameter of the substrate particle When the region of is referred to as region R1, in 100% of the total number of conductive particles, the ratio of the number of conductive particles of the conductive metal present in the region R1 of the substrate particle is 50% or more.

In a specific aspect of the conductive material of the present invention, the conductive material includes a plurality of the conductive particles, and the distance from the center of the substrate particle toward the outer surface is 1/2 of the particle diameter of the substrate particle When the region of is referred to as region R2, in 100% of the total number of conductive particles, the ratio of the number of conductive particles of the conductive metal present in the region R2 of the substrate particle is 5% or more.

According to a broad aspect of the present invention, there is provided a connection structure including: a first connection object member having a first electrode on the surface; a second connection object member having a second electrode on the surface; and a connection portion, It connects the first connection object member and the second connection object member; the material of the connection portion is the conductive particles, or a conductive material containing the conductive particles and a binder resin, the first electrode and the second The electrodes are electrically connected by the above-mentioned conductive particles. [Effects of Invention]

The electroconductive particle of this invention is equipped with the conductive part arrange|positioned on the surface of the base particle and the said base particle. In the conductive particle of the present invention, the substrate particle contains a conductive metal in the interior of the substrate particle. Since the conductive particles of the present invention have the above-mentioned structure, the connection resistance between the electrodes can be effectively reduced, and the occurrence of aggregation of the conductive particles can be effectively suppressed.

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

(Conductive particles) The electroconductive particle of this invention is equipped with the conductive part arrange|positioned on the surface of the base particle and the said base particle. In the conductive particle of the present invention, the substrate particle contains a conductive metal in the interior of the substrate particle.

Since the conductive particles of the present invention have the above-mentioned structure, the connection resistance between the electrodes can be effectively reduced, and the occurrence of aggregation of the conductive particles can be effectively suppressed.

In order to sufficiently reduce the connection resistance between the electrodes in the vertical direction when manufacturing a connection structure by using conductive particles with a small particle diameter to connect the electrodes, the thickness of the conductive part in the conductive particles may be increased. However, if the thickness of the conductive part is increased, when the conductive part is formed by plating, the conductive particles may aggregate. When agglomeration of conductive particles occurs, the electrodes adjacent to each other in the lateral direction are often easily connected, and it may be difficult to improve the insulation reliability between the electrodes adjacent in the lateral direction.

In addition, if the thickness of the conductive part is made thin to suppress the aggregation of conductive particles, when the conductive part is formed by plating, although the aggregation of the conductive particles can be suppressed, it is difficult to sufficiently reduce the connection between the electrodes in the vertical direction resistance. In the conventional conductive particles, it is difficult to balance the reduction of the connection resistance between the electrodes and the suppression of the aggregation of the conductive particles.

The inventors of the present invention found that by using specific conductive particles, both the reduction of the connection resistance between the electrodes and the suppression of the aggregation of conductive particles can be achieved. In the present invention, when the electrodes in the vertical direction are connected, the conductive particles are compressed, thereby not only forming a conduction path on the surface (conductive part) of the conductive particle, but also in the interior of the conductive particle (conductive part). Metal) forms a conduction path. In addition, even if the conductive metal inside the conductive particles does not form a complete conduction path, it is very helpful to reduce the connection resistance. As a result, even when the thickness of the conductive portion is relatively thin, the connection resistance between the electrodes in the vertical direction can be sufficiently reduced. In addition, since the thickness of the conductive portion is relatively thin, the occurrence of aggregation of conductive particles can be suppressed, and the insulation reliability between adjacent electrodes in the lateral direction that should not be connected can be effectively improved. In the present invention, since the above-mentioned structure is provided, the connection resistance between the electrodes can be effectively reduced, and the occurrence of aggregation of conductive particles can be effectively suppressed. Furthermore, in the present invention, a conductive path (conductive portion) is formed not only on the surface of the substrate particle, but also inside the substrate particle, and the conductive path (conductive portion) can enter the interior of the substrate particle. As a result, the adhesion of the conductive part in the conductive particle can be effectively improved, and the occurrence of peeling of the conductive part in the conductive particle can be effectively suppressed.

In the present invention, in order to obtain the above-mentioned effects, the use of specific conductive particles is of great help.

The 10% K value (compression modulus of elasticity when compressed by 10%) of the aforementioned conductive particles is preferably 100 N/mm ² or more, more preferably 1000 N/mm ² or more, and preferably 25000 N/mm ² or less, More preferably, it is 20,000 N/mm ² or less. If the 10% K value of the conductive particles is above the above lower limit and below the above upper limit, the connection resistance between the electrodes can be further effectively reduced, the occurrence of cracking of the conductive particles can be further effectively suppressed, and the occurrence of the conductive particles can be further effectively reduced Ground improves the reliability of the connection between the electrodes.

The 30% K value (compression modulus of elasticity when compressed by 30%) of the above conductive particles is preferably 100 N/mm ² or more, more preferably 1000 N/mm ² or more, and preferably 15000 N/mm ² or less, More preferably, it is 10000 N/mm ² or less. If the 30% K value of the conductive particles is above the above lower limit and below the above upper limit, the connection resistance between the electrodes can be further effectively reduced, and the occurrence of cracking of the conductive particles can be further effectively suppressed, which can be more effective Ground improves the reliability of the connection between the electrodes.

The ratio of the 10% K value of the conductive particles to the 30% K value of the conductive particles (10% K value of the conductive particles/30% K value of the conductive particles) is preferably 1.5 or more, more preferably 1.55 or more, preferably 5 or less, more preferably 4.5 or less. If the above ratio (10% K value of conductive particles/30% K value of conductive particles) is above the above lower limit and below the above upper limit, the connection resistance between the electrodes can be further effectively reduced, and the resistance can be further effectively suppressed The occurrence of cracking of the conductive particles can further effectively improve the reliability of the connection between the electrodes.

The 10% K value and the 30% K value in the conductive particles can be measured as follows.

Using a micro-compression tester, compress a conductive particle on the end face of a cylindrical (100 μm diameter, manufactured by DIAMOND) smooth indenter at 25°C, a compression speed of 0.3 mN/sec, and a maximum test load of 20 mN . Measure the load value (N) and compression displacement (mm) at this time. The above-mentioned compression modulus (10% K value and 30% K value) can be obtained from the measured value obtained according to the following formula. As the above-mentioned micro-compression tester, "Fischerscope H-100" manufactured by Fischer Corporation or the like is used. The 10% K value and the 30% K value in the conductive particles are preferably calculated by arithmetic average of the 10% K value and 30% K value of 50 arbitrarily selected conductive particles.

10%K value and 30%K value (N/mm ² )=(3/2 ^1/2 )・F・S ^-3/2・R ^-1/2 F: Conductive particle compression deformation 10% or 30% Load value at time (N) S: Compression displacement when conductive particle is compressed and deformed by 10% or 30% (mm) R: Radius of conductive particle (mm)

The above-mentioned compression elastic modulus generally and quantitatively indicates the hardness of the conductive particles. By using the above-mentioned compression modulus, the hardness of the conductive particles can be quantitatively and uniquely expressed. In addition, the above ratio (10% K value of conductive particles/30% K value of conductive particles) can quantitatively and uniquely indicate the physical properties of the conductive particles at the time of initial compression.

The particle size of the conductive particles is preferably 0.1 μm or more, more preferably 1 μm or more, preferably 1000 μm or less, and more preferably 10 μm or less. If the particle size of the conductive particles is greater than or equal to the above lower limit and less than or equal to the above upper limit, when the conductive particles are used to connect the electrodes, the contact area between the conductive particles and the electrode becomes sufficiently large and the conductive portion is formed It is not easy to form agglomerated conductive particles. In addition, the gap between the electrodes connected via the conductive particles does not become too large, and the conductive portion is not easily peeled off from the surface of the substrate particle.

The particle diameter of the conductive particles is preferably an average particle diameter, and more preferably a number average particle diameter. The particle size of the above-mentioned conductive particles is obtained by observing any 50 conductive particles with an electron microscope or an optical microscope, and calculating the average value of the particle sizes of each conductive particle, or using a particle size distribution measuring device. In observation with an electron microscope or an optical microscope, the particle size per conductive particle is calculated as the particle size in terms of equivalent circle diameter. In observation with an electron microscope or an optical microscope, the average particle diameter in terms of circle equivalent diameter of any 50 conductive particles is approximately the same as the average particle diameter in terms of spherical equivalent diameter. In the particle size distribution measuring device, the particle size per conductive particle is calculated as the particle size based on the equivalent diameter of the sphere. The average particle size of the conductive particles is preferably calculated using a particle size distribution measuring device.

The coefficient of variation (CV value) of the particle diameter of the conductive particles is preferably 10% or less, more preferably 5% or less. If the coefficient of variation of the particle diameter of the conductive particles is equal to or less than the upper limit, the conduction reliability and insulation reliability between electrodes can be further effectively improved.

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

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

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

Hereinafter, the present invention will be specifically described with reference to the drawings.

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

The conductive particle 1 shown in FIG. 1 has a base particle 2 and a conductive part 3. The conductive part 3 is arranged on the surface of the substrate particle 2. In the first embodiment, the conductive portion 3 is in contact with the surface of the substrate particle 2. The conductive particle 1 is a coated particle in which the surface of the substrate particle 2 is covered with the conductive portion 3.

In the conductive particle 1, the conductive part 3 is a single-layer conductive layer. In the conductive particle 1, the substrate particle 2 contains a conductive metal inside the substrate particle 2. In the conductive particles, the conductive portion may cover the entire surface of the substrate particle, and the conductive portion may cover a part of the surface of the substrate particle. In the above-mentioned conductive particles, the above-mentioned conductive part may be a single-layer conductive layer, or may be a multilayer conductive layer including two or more layers.

The conductive particle 1 is different from the following conductive particles 11 and 21 and does not have a core material. The conductive particle 1 does not have protrusions on the surface. The conductive particles 1 are spherical. The conductive part 3 does not have protrusions on the outer surface. In this way, the conductive particles of the present invention may not have protrusions on the conductive surface, or may be spherical. In addition, the conductive particle 1 is different from the following conductive particles 11 and 21 in that it does not have an insulating substance. However, the conductive particles 1 may have an insulating substance arranged on the outer surface of the conductive part 3.

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

The conductive particle 11 shown in FIG. 2 has a substrate particle 2, a conductive portion 12, a plurality of core materials 13, and a plurality of insulating materials 14. The conductive portion 12 is arranged on the surface of the substrate particle 2 so as to be in contact with the substrate particle 2.

In the conductive particles 11, the conductive portion 12 is a single-layer conductive layer. In the conductive particle 11, the substrate particle 2 contains a conductive metal inside the substrate particle 2. In the conductive particles, the conductive portion may cover the entire surface of the substrate particle, and the conductive portion may cover a part of the surface of the substrate particle. In the above-mentioned conductive particles, the above-mentioned conductive part may be a single-layer conductive layer, or may be a multilayer conductive layer including two or more layers.

The conductive particle 11 has a plurality of protrusions 11a on the conductive surface. The conductive portion 12 has a plurality of protrusions 12a on the outer surface. A plurality of core materials 13 are arranged on the surface of the substrate particle 2. A plurality of core materials 13 are embedded in the conductive part 12. The core material 13 is arranged inside the protrusions 11a and 12a. The conductive part 12 covers a plurality of core materials 13. The outer surface of the conductive portion 12 is raised by a plurality of core materials 13 to form protrusions 11a and 12a.

The conductive particles 11 have an insulating substance 14 arranged on the outer surface of the conductive part 12. At least a part of the outer surface of the conductive portion 12 is covered with an insulating material 14. The insulating substance 14 is formed of an insulating material and is an insulating particle. In this way, the conductive particle of the present invention may have an insulating substance arranged on the outer surface of the conductive part. However, the conductive particles of the present invention may not necessarily have insulating materials.

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

The conductive particle 21 shown in FIG. 3 has a substrate particle 2, a conductive portion 22, a plurality of core materials 13, and a plurality of insulating materials 14. The entire conductive portion 22 has a first conductive portion 22A on the side of the substrate particle 2 and a second conductive portion 22B on the side opposite to the side of the substrate particle 2.

In the conductive particle 11 and the conductive particle 21, only a conductive part is different. That is, in the conductive particle 11, the conductive part 12 of a 1-layer structure is formed, and in contrast to this, in the conductive particle 21, the 1st conductive part 22A and the 2nd conductive part 22B of a 2-layer structure are formed. The first conductive portion 22A and the second conductive portion 22B are formed as different conductive portions.

The first conductive portion 22A is arranged on the surface of the substrate particle 2. The first conductive portion 22A is arranged between the substrate particle 2 and the second conductive portion 22B. The first conductive portion 22A is in contact with the substrate particle 2. The second conductive portion 22B is in contact with the first conductive portion 22A. Therefore, the first conductive portion 22A is arranged on the surface of the substrate particle 2, and the second conductive portion 22B is arranged on the surface of the first conductive portion 22A. The conductive particle 21 has a plurality of protrusions 21a on the conductive surface. The conductive portion 22 has a plurality of protrusions 22a on the outer surface. The first conductive portion 22A has a plurality of protrusions 22Aa on the outer surface. The second conductive portion 22B has a plurality of protrusions 22Ba on the outer surface.

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

(Substrate particles) The material of the aforementioned substrate particles is not particularly limited. The material of the aforementioned substrate particles may be organic materials or inorganic materials. Examples of substrate particles made of only the above-mentioned organic materials include resin particles. Examples of substrate particles made of only the above-mentioned inorganic materials include inorganic particles other than metals. Examples of substrate particles formed of both the above-mentioned organic material and the above-mentioned inorganic material include organic-inorganic hybrid particles. From the viewpoint of further improving the compression characteristics of the substrate particles, the substrate particles are preferably resin particles or organic-inorganic hybrid particles, and more preferably resin particles.

Examples of the above-mentioned organic materials include polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene, and polybutadiene; polymethyl methacrylate and polymethyl acrylate Acrylic resins such as esters; polycarbonate, polyamide, phenol-formaldehyde resin, melamine-formaldehyde resin, benzoguanamine-formaldehyde resin, urea-formaldehyde resin, phenolic resin, melamine resin, benzoguanamine resin, Urea resin, epoxy resin, unsaturated polyester resin, saturated polyester resin, polyethylene terephthalate, polysulfide, polyphenylene ether, polyacetal, polyimide, polyimide imide, Polyether ether ketone, polyether clump, divinylbenzene polymer, and divinylbenzene copolymer, etc. As said divinylbenzene copolymer etc., a divinylbenzene-styrene copolymer, a divinylbenzene-(meth)acrylate copolymer, etc. are mentioned. Since the compression characteristics of the substrate particles can be easily controlled to a preferable range, the material of the substrate particles is preferably formed by polymerizing one or more polymerizable monomers having ethylenically unsaturated groups polymer.

In the case of polymerizing a polymerizable monomer having an ethylenically unsaturated group to obtain the substrate particles, examples of the polymerizable monomer having an ethylenically unsaturated group include non-crosslinkable monomers and crosslinking The monomer of sex.

Examples of the above-mentioned non-crosslinkable monomers include: vinyl compounds such as styrene monomers such as styrene, α-methylstyrene, and chlorostyrene; methyl vinyl ether, ethyl vinyl ether, acrylic Vinyl ether compounds such as vinyl ether; vinyl acetate, vinyl butyrate, vinyl laurate, and vinyl stearate; halogen-containing monomers such as vinyl chloride and vinyl fluoride; as (methyl ) Acrylic compounds of 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, cyclohexyl (meth)acrylate, iso-(meth)acrylate and other alkyl (meth)acrylates Ester compound; (meth)acrylic acid containing oxygen atoms such as 2-hydroxyethyl (meth)acrylate, glycerol (meth)acrylate, polyoxyethylene (meth)acrylate, glycidyl (meth)acrylate, etc. Ester compound; nitrile-containing monomers such as (meth)acrylonitrile; halogen-containing (meth)acrylate compounds such as methyl trifluoro(meth)acrylate and ethyl pentafluoro(meth)acrylate; as α-olefin compounds Diisobutylene, isobutylene, Linealene, ethylene, propylene and other olefin compounds; as conjugated diene compounds, isoprene, butadiene, etc.

Examples of the above-mentioned crosslinkable monomers include: vinyl monomers such as divinylbenzene, 1,4-divinyloxybutane, and divinyl sulfonate as vinyl compounds; as (meth)acrylic compounds Tetramethylolmethane tetra(meth)acrylate, polytetramethylene glycol diacrylate, tetramethylolmethane tri(meth)acrylate, tetramethylolmethane di(meth)acrylate , Trimethylolpropane tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate, glycerol tri(meth)acrylate, glycerol di(meth)acrylate Ester, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, 1,4-butanediol bis(methyl) ) Polyfunctional (meth)acrylate compounds such as acrylates; triallyl isocyanurate, triallyl trimellitate, diallyl phthalate, diallyl as allyl compounds Acrylamide, diallyl ether; tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyl trisane as silane compounds Ethoxysilane, isopropyltrimethoxysilane, isobutyltrimethoxysilane, cyclohexyltrimethoxysilane, n-hexyltrimethoxysilane, n-octyltriethoxysilane, n-decyltrimethoxysilane Silane, phenyltrimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diisopropyldimethoxysilane, trimethoxysilylstyrene, γ-(methyl ) Silane alkoxides such as acryloxypropyltrimethoxysilane, 1,3-divinyltetramethyldisiloxane, methylphenyldimethoxysilane, and diphenyldimethoxysilane Compounds; vinyl trimethoxy silane, vinyl triethoxy silane, dimethoxy methyl vinyl silane, dimethoxy ethyl vinyl silane, diethoxy methyl vinyl silane, diethoxy Base ethyl vinyl silane, ethyl methyl divinyl silane, methyl vinyl dimethoxy silane, ethyl vinyl dimethoxy silane, methyl vinyl diethoxy silane, ethyl vinyl Diethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3- Methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, etc. contain polymerizable double bonds Silane alkoxides; Cyclic siloxanes such as decamethylcyclopentasiloxane; Modified polysiloxane oil at one end, polysiloxane oil at both ends, side chain polysiloxane oil, etc. (reactive ) Polysiloxane oil; (meth)acrylic acid, maleic acid, maleic anhydride and other carboxyl-containing monomers.

The substrate particles can be obtained by polymerizing the polymerizable monomer having the ethylenically unsaturated group. The polymerization method is not particularly limited, and examples include known methods such as radical polymerization, ionic polymerization, polycondensation (condensation polymerization, condensation polymerization), addition condensation, living polymerization, and living radical polymerization. Furthermore, as another polymerization method, suspension polymerization in the presence of a radical polymerization initiator can be cited.

Examples of the above-mentioned inorganic materials include silicon dioxide, aluminum oxide, barium titanate, zirconium oxide, carbon black, silicate glass, borosilicate glass, lead glass, soda lime glass, and aluminosilicate glass.

The aforementioned substrate particles may be organic-inorganic hybrid particles. The aforementioned substrate particles may be core-shell particles. When the substrate particle is an organic-inorganic hybrid particle, the inorganic substance of the material of the substrate particle includes silica, alumina, barium titanate, zirconia, carbon black, and the like. The above-mentioned inorganic substance is preferably not a metal. The substrate particles formed of the above-mentioned silicon dioxide are not particularly limited, and examples thereof include crosslinked polymer particles formed by hydrolyzing a silicide having two or more hydrolyzable alkoxysilyl groups and then calcining as necessary. The obtained substrate particles. Examples of the organic-inorganic hybrid particles include organic-inorganic hybrid particles formed of a crosslinked alkoxysilyl polymer and acrylic resin.

The organic-inorganic hybrid particles are preferably core-shell type organic-inorganic hybrid particles having a core and a shell arranged on the surface of the core. The aforementioned core is preferably an organic core. The aforementioned shell is preferably an inorganic shell. 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.

Examples of the above-mentioned organic core material include the above-mentioned organic materials.

As the material of the above-mentioned inorganic shell, the inorganic substances exemplified above as the material of the substrate particles can be cited. The material of the aforementioned inorganic shell is preferably silicon dioxide. The above-mentioned inorganic shell is preferably formed by forming a metal alkoxide on the surface of the core by a sol-gel method into a shell, and then calcining the shell. The above-mentioned metal alkoxide is preferably a silane alkoxide. The above-mentioned inorganic shell is preferably formed of silane alkoxide.

The BET (Brunauer-Emmett-Teller) specific surface area of the substrate particles is preferably 8 m ² /g or more, more preferably 12 m ² /g or more, preferably 1200 m ² /g or less, more It is preferably 1000 m ² /g or less. If the BET specific surface area is greater than or equal to the aforementioned lower limit and less than or equal to the aforementioned upper limit, the conductive metal can be contained in the substrate particles more easily. If the BET specific surface area is greater than or equal to the aforementioned lower limit and less than or equal to the aforementioned upper limit, the connection resistance between the electrodes can be further effectively reduced, and the occurrence of aggregation of conductive particles can be further effectively suppressed. Moreover, if the BET specific surface area is greater than or equal to the lower limit and less than or equal to the upper limit, the insulation reliability between the electrodes can be further effectively improved. In addition, if the BET specific surface area is more than the lower limit and less than the upper limit, the adhesion of the conductive part in the conductive particle can be further effectively improved, and the occurrence of peeling of the conductive part in the conductive particle can be further effectively suppressed .

The BET specific surface area of the substrate particles can be measured from the adsorption isotherm of nitrogen according to the BET method. As an apparatus for measuring the BET specific surface area of the substrate particles, "NOVA4200e" manufactured by Quantachrome Instruments, etc. can be cited.

The total pore volume of the substrate particles is preferably 0.01 cm ³ /g or more, more preferably 0.1 cm ³ /g or more, preferably 3 cm ³ /g or less, and more preferably 1.5 cm ³ /g or less. If the total pore volume is greater than or equal to the aforementioned lower limit and less than or equal to the aforementioned upper limit, the conductive metal can be contained in the substrate particles more easily. If the total pore volume is greater than or equal to the aforementioned lower limit and less than or equal to the aforementioned upper limit, the connection resistance between the electrodes can be further effectively reduced, and the occurrence of aggregation of conductive particles can be further effectively suppressed. In addition, if the total pore volume is greater than or equal to the lower limit and less than or equal to the upper limit, the insulation reliability between electrodes can be further effectively improved. In addition, if the total pore volume is greater than or equal to the above lower limit and less than or equal to the above upper limit, the adhesion of the conductive parts in the conductive particles can be further effectively improved, and peeling of the conductive parts in the conductive particles can be further effectively suppressed occur.

The total pore volume of the above-mentioned substrate particles can be measured from the nitrogen adsorption isotherm according to the BJH (Barrett-Joyner-Halenda, Barrett-Joyner-Halenda) method. As an apparatus for measuring the total pore volume of the substrate particles, "NOVA4200e" manufactured by Quantachrome Instruments, etc. can be cited.

The average pore diameter of the substrate particles is preferably 10 nm or less, more preferably 5 nm or less. The lower limit of the average pore diameter of the substrate particles is not particularly limited. The average pore diameter of the substrate particles may be 1 nm or more. If the average pore diameter is greater than or equal to the aforementioned lower limit and less than or equal to the aforementioned upper limit, the conductive metal can be contained in the substrate particles more easily. If the average pore diameter is greater than or equal to the aforementioned lower limit and less than or equal to the aforementioned upper limit, the connection resistance between electrodes can be reduced more effectively, and the occurrence of aggregation of conductive particles can be more effectively suppressed. In addition, if the average pore diameter is greater than or equal to the lower limit and less than or equal to the upper limit, the insulation reliability between the electrodes can be further effectively improved. Moreover, if the average pore diameter is more than the lower limit and less than the upper limit, the adhesion of the conductive part in the conductive particle can be further effectively improved, and the occurrence of peeling of the conductive part in the conductive particle can be further effectively suppressed .

The average pore diameter of the substrate particles can be measured from the adsorption isotherm of nitrogen according to the BJH method. As an apparatus for measuring the average pore diameter of the substrate particles, "NOVA4200e" manufactured by Quantachrome Instruments, etc. can be cited.

The porosity of the substrate particles is preferably 5% or more, more preferably 10% or more, preferably 90% or less, and more preferably 70% or less. If the porosity is equal to or higher than the lower limit and equal to or lower than the upper limit, the conductive metal can be contained in the substrate particles more easily. If the porosity is greater than or equal to the aforementioned lower limit and less than or equal to the aforementioned upper limit, the connection resistance between electrodes can be further effectively reduced, and the occurrence of aggregation of conductive particles can be further effectively suppressed. In addition, if the porosity is greater than or equal to the lower limit and less than or equal to the upper limit, the insulation reliability between electrodes can be further effectively improved. In addition, if the porosity is greater than or equal to the lower limit and less than or equal to the upper limit, the adhesion of the conductive portion in the conductive particle can be further effectively improved, and the occurrence of peeling of the conductive portion in the conductive particle can be further effectively suppressed.

The porosity of the substrate particles can be calculated by measuring the cumulative infiltration amount of mercury with respect to the pressure applied by the mercury permeation method. As a measuring device for the porosity of the substrate particles, a mercury porosimeter "PoreMaster 60" manufactured by Quantachrome Instruments can be cited.

The substrate particles satisfying the preferable ranges of the above-mentioned BET specific surface area and the above-mentioned porosity can be obtained, for example, by a method for producing substrate particles having the following steps. The step of mixing a polymerizable monomer and an organic solvent that does not react with the above-mentioned polymerizable monomer to adjust the polymerizable monomer solution. The step of adding the above-mentioned polymerizable monomer solution and an anionic dispersion stabilizer to a polar solvent to emulsify it to obtain an emulsion. The step of adding the above-mentioned emulsion several times to make the seed particles absorb the monomer to obtain a suspension containing the seed particles swelled by the monomer. The step of polymerizing the above-mentioned polymerizable monomer to obtain substrate particles. As said polymerizable monomer, a monofunctional monomer, a polyfunctional monomer, etc. are mentioned. The organic solvent that does not react with the above-mentioned polymerizable monomer is not particularly limited as long as it is incompatible with a polar solvent such as water as a polymerization medium. As said organic solvent, cyclohexane, toluene, xylene, ethyl acetate, butyl acetate, allyl acetate, propyl acetate, chloroform, methyl cyclohexane, methyl ethyl ketone, etc. are mentioned. The addition amount of the organic solvent is preferably 105 parts by weight to 215 parts by weight, and more preferably 110 parts by weight to 210 parts by weight with respect to 100 parts by weight of the polymerizable monomer components. If the addition amount of the organic solvent is in the above-mentioned preferable range, the BET specific surface area, porosity, etc. can be controlled to a still more preferable range, and it is easy to obtain dense pores inside the particles.

The substrate particles satisfying the preferred ranges of the above-mentioned BET specific surface area and the above-mentioned porosity have relatively many voids inside the substrate particles. Therefore, when a conductive portion is formed on the surface of the substrate particle, the conductive portion enters the substrate particle In the fine voids inside, conductive metal can be easily contained in the substrate particles. Furthermore, in the above-mentioned conductive particles, it is preferable that when the electrodes in the vertical direction are connected, the conductive particles are compressed, whereby the conductive metals in the base particles are brought into contact with each other, thereby forming a conduction path. In the above-mentioned conductive particles, a conductive path is formed not only in the surface (conductive portion) of the conductive particle, but also in the interior (conductive metal) of the conductive particle. As a result, even when the thickness of the conductive portion is relatively thin, the connection resistance between the electrodes in the vertical direction can be sufficiently reduced. In addition, since the thickness of the conductive portion is relatively thin, the occurrence of aggregation of conductive particles can be suppressed, and the insulation reliability between adjacent electrodes in the lateral direction that should not be connected can be effectively improved. Moreover, in the above-mentioned conductive particles, when the conductive part is formed on the surface of the substrate particle, the conductive part enters the fine voids inside the substrate particle, so that the adhesion of the conductive part in the conductive particle can be effectively improved , Can effectively suppress the occurrence of peeling of the conductive part in the conductive particles.

The particle diameter of the aforementioned substrate particles is preferably 0.1 μm or more, more preferably 1 μm or more. The particle size of the substrate particles is preferably 1000 μm or less, more preferably 500 μm or less, still more preferably 300 μm or less, still more preferably 50 μm or less, and still more preferably 10 μm or less. If the particle size of the substrate particles is greater than or equal to the above lower limit, the contact area between the conductive particles and the electrode becomes larger. Therefore, the reliability of conduction between the electrodes can be further improved, and the number of electrodes connected via the conductive particles can be further reduced. The connection resistance between. Furthermore, when the conductive part is formed on the surface of the substrate particle by electroless plating, it is difficult to form agglomerated conductive particles. If the particle size of the substrate particles is equal to or less than the above upper limit, the conductive particles can be easily compressed sufficiently, the connection resistance between the electrodes can be further reduced, and the gap between the electrodes can be further reduced.

The particle size of the substrate particles is particularly preferably 1 μm or more and 3 μm or less. If the particle size of the substrate particle is within the range of 1 μm or more and 3 μm or less, it is unlikely that agglomeration will occur when the conductive portion is formed on the surface of the substrate particle, and agglomerated conductive particles will not easily form.

The particle size of the above-mentioned substrate particles means the number average particle size. The particle size of the above-mentioned substrate particles is obtained by observing any 50 substrate particles with an electron microscope or an optical microscope, and calculating the average value of the particle size of each substrate particle, or using a particle size distribution measuring device. In observation with an electron microscope or an optical microscope, the particle size per substrate particle is calculated as the particle size in terms of equivalent circle diameter. In observation with an electron microscope or an optical microscope, the average particle diameter in terms of circle equivalent diameter of any 50 substrate particles is approximately the same as the average particle diameter in terms of spherical equivalent diameter. In the particle size distribution measuring device, the particle size per substrate particle is calculated as the particle size calculated as the equivalent diameter of the sphere. The average particle size of the substrate particles is preferably calculated using a particle size distribution measuring device. In the case of measuring the particle diameter of the above-mentioned substrate particles in the conductive particles, for example, the measurement can be performed as follows.

The conductive particles were added to "Technovit 4000" manufactured by Kulzer Corporation so that the content of the conductive particles became 30% by weight, and dispersed to prepare embedded resin for conductive particle inspection. The cross-section of the conductive particles was cut out using an ion milling device ("IM4000" manufactured by Hitachi High-Technologies) to pass the vicinity of the center of the conductive particles dispersed in the embedded resin for inspection. Then, using a field emission scanning electron microscope (FE-SEM), the image magnification was set to 25000 times, 50 conductive particles were randomly selected, and the substrate particles of each conductive particle were observed. The particle diameter of the substrate particle in each conductive particle is measured, and the arithmetic average of these is used as the particle diameter of the substrate particle.

(Conductive part and conductive metal) The electroconductive particle of this invention is equipped with the conductive part arrange|positioned on the surface of the base particle and the said base particle. In the conductive particle of the present invention, the substrate particle contains a conductive metal in the interior of the substrate particle. The aforementioned conductive portion preferably contains metal. The metal constituting the aforementioned conductive portion is not particularly limited. The aforementioned conductive metal is not particularly limited. The metal constituting the conductive portion and the conductive metal may be the same metal or different metals. The metal contained most in the conductive portion and the metal contained most in the conductive metal are preferably the same.

Examples of the metal constituting the conductive portion and the conductive metal include gold, silver, palladium, copper, platinum, zinc, iron, tin, lead, aluminum, cobalt, indium, nickel, chromium, titanium, antimony, bismuth, Thallium, germanium, cadmium, silicon, tungsten, molybdenum and their alloys, etc. In addition, examples of the metal constituting the conductive portion and the conductive metal include tin-doped indium oxide (ITO), solder, and the like. The metal constituting the conductive portion and the conductive metal may be used alone or in combination of two or more.

From the viewpoint of further effectively reducing the connection resistance between the electrodes, the conductive portion preferably includes nickel, gold, palladium, silver, or copper, and more preferably includes nickel, gold, or palladium.

The content of nickel in 100% by weight of the conductive portion containing nickel is preferably 10% by weight or more, more preferably 50% by weight or more, still more preferably 60% by weight or more, and still more preferably 70% by weight or more, particularly More than 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.

Furthermore, on the surface of the conductive part, hydroxyl groups are present due to oxidation in most cases. Generally speaking, on the surface of the conductive part formed of nickel, hydroxyl groups are present due to oxidation. An insulating substance can be arranged on the surface of such a conductive part having a hydroxyl group (the surface of the conductive particle) through chemical bonding.

The above-mentioned conductive portion may be formed in one layer. The above-mentioned conductive part may be formed of a plurality of layers. That is, the said conductive part may have a laminated structure of two or more layers. In the case where the above-mentioned conductive part is formed of a plurality of layers, the metal constituting the outermost layer preferably includes gold, nickel, palladium, copper, or an alloy of tin and silver, and more preferably gold. When the metal constituting the outermost layer is the better metal, the connection resistance between the electrodes is further reduced. In addition, when the metal constituting the outermost layer is gold, the corrosion resistance is further improved.

The method of forming a conductive part on the surface of the said base material particle is not specifically limited. As the method of forming the above-mentioned conductive part, there can be mentioned: the method of electroless plating, the method of electroplating, the method of physical collision, the method of mechanochemical reaction, the method of physical vapor deposition or physical adsorption, and the method of metal The method of coating powder or paste containing metal powder and adhesive on the surface of substrate particles, etc. The method of forming the aforementioned conductive portion is preferably a method using electroless plating, electroplating, or physical collision. As the method using the physical vapor deposition described above, methods such as vacuum vapor deposition, ion plating, and ion sputtering can be cited. In addition, as a method of utilizing physical collision as described above, Thetacomposer (manufactured by Tokuju Works Co., Ltd.) or the like is used.

The method of making the inside of the said base material particle contain a conductive metal is not specifically limited. As a method of containing a conductive metal in the above-mentioned substrate particles, there may be mentioned: a method of electroless plating using a substrate particle (substrate particle body) as a porous particle, and the use of a substrate as a porous particle The method of electroplating the particles (substrate particle body), etc. The substrate particles (substrate particle body) as porous particles have relatively many voids inside the substrate particles. Therefore, when the conductive portion is formed on the surface of the substrate particle, the conductive portion forming material (plating solution Etc.) Into the fine voids inside the substrate particles. By precipitating the conductive metal from the conductive part forming material that enters the substrate particle, the conductive metal can be easily contained in the substrate particle. Examples of the substrate particles of the porous particles include substrate particles that satisfy the above-mentioned BET specific surface area, the above-mentioned porosity, and the like.

The thickness of the conductive portion is preferably 0.005 μm or more, more preferably 0.01 μm or more, preferably 10 μm or less, more preferably 1 μm or less, and still more preferably 0.3 μm or less. When the conductive portion is a multilayer, the thickness of the conductive portion is the thickness of the entire conductive portion. If the thickness of the conductive part is greater than or equal to the above lower limit and less than or equal to the above upper limit, sufficient conductivity can be obtained, the conductive particles will not become too hard, and the conductive particles can be sufficiently deformed when the electrodes are connected.

When the above-mentioned conductive portion is formed of multiple layers, the thickness of the conductive portion of the outermost layer is preferably 0.001 μm or more, more preferably 0.01 μm or more, preferably 0.5 μm or less, and more preferably 0.1 μm or less. If the thickness of the conductive portion of the outermost layer is more than the lower limit and less than the upper limit, the coating by the conductive portion of the outermost layer becomes uniform, the corrosion resistance becomes sufficiently high, and the connection resistance between the electrodes can be sufficiently reduced. Moreover, when the metal constituting the outermost layer is gold, the thinner the thickness of the outermost layer, the more cost can be reduced.

The thickness of the said conductive part can be measured by observing the cross section of a conductive particle using a transmission electron microscope (TEM), for example. Regarding the thickness of the above-mentioned conductive part, it is preferable to calculate the average value of the thickness of 5 parts of any conductive part as the thickness of the conductive part of one conductive particle, and it is more preferable to calculate the average thickness of the whole conductive part as one The thickness of the conductive part of the conductive particle. It is preferable that the thickness of the said electroconductive part is calculated|required by calculating the average value of the thickness of the electroconductive part of each electroconductive particle for arbitrary 10 electroconductive particles.

In 100% by volume of the conductive particles, the content of the conductive metal is preferably 5% by volume or more, more preferably 10% by volume or more, preferably 70% by volume or less, and more preferably 50% by volume or less. If the content of the conductive metal is not less than the above lower limit and not more than the above upper limit, the connection resistance between the electrodes can be further effectively reduced, and the occurrence of aggregation of conductive particles can be further effectively suppressed. Moreover, if the content of the conductive metal is greater than or equal to the aforementioned lower limit and less than or equal to the aforementioned upper limit, the insulation reliability between electrodes can be further effectively improved. In addition, if the content of the conductive metal is more than the lower limit and less than the upper limit, the adhesion of the conductive part in the conductive particle can be further effectively improved, and the peeling of the conductive part in the conductive particle can be further effectively suppressed It happened. From the viewpoint of further improving the compression characteristics of the conductive particles, the content of the conductive metal in 100% by volume of the conductive particles is preferably 5% by volume or more, more preferably 10% by volume or more, and more preferably 50% by volume % Or less, more preferably 40 volume% or less. From the viewpoint of further effectively reducing the connection resistance between electrodes, the content of the conductive metal in 100% by volume of the conductive particles is preferably 10% by volume or more, more preferably 20% by volume or more, and more preferably 50% by volume. The volume% or less, more preferably 40 volume% or less. In 100% by volume of the conductive particles, the content of the conductive metal is particularly preferably 10% by volume or more and 40% by volume or less. If the content of the conductive metal is within the range of 10% by volume to 40% by volume, both the improvement of the compression properties of the conductive particles and the reduction of the connection resistance between the electrodes can be achieved at a higher level. In addition, the content of the conductive metal means the total content of the metal constituting the conductive portion and the conductive metal contained in the substrate particles. Whether or not a conductive metal is contained in the substrate particles is preferably determined based on the following first ratio and second ratio.

The content of the conductive metal can be calculated as follows.

The content of conductive metal (vol%) = D×M/Dmetal×100 D: Specific gravity of conductive particles M: Metallization rate of conductive particles Dmetal: Specific gravity of conductive metal

Furthermore, the metallization rate of the conductive particles can be calculated by ICP (Inductively Coupled Plasma) luminescence analysis or the like, and the specific gravity of the conductive particles can be measured using a true hydrometer or the like. In addition, the specific gravity of the conductive metal can be calculated using the value inherent to the metal. Furthermore, the metallization rate of conductive particles refers to the ratio of the content (g) of conductive metal contained in 1 g of conductive particles, that is, the content of conductive metal contained in 1 g of conductive particles ( g)/ 1 g of conductive particles.

In 100% by volume of the conductive particles, the content of the conductive metal contained in the substrate particles is preferably 0.1% by volume or more, more preferably 1% by volume or more, preferably 30% by volume or less, and more preferably 20% by volume or less. If the content of the conductive metal is not less than the above lower limit and not more than the above upper limit, the connection resistance between the electrodes can be further effectively reduced, and the occurrence of aggregation of conductive particles can be further effectively suppressed. In addition, if the content of the conductive metal is more than the lower limit and less than the upper limit, the adhesion of the conductive part in the conductive particle can be further effectively improved, and the peeling of the conductive part in the conductive particle can be further effectively suppressed It happened.

From the viewpoint of further improving the compression characteristics of conductive particles, the content of the conductive metal contained in the conductive portion in 100% by volume of the conductive particles is preferably 0.1% by volume or more, more preferably 1 volume % Or more, preferably 30% by volume or less, more preferably 20% by volume or less. From the viewpoint of further effectively reducing the connection resistance between electrodes, the content of the conductive metal contained in the conductive portion in 100% by volume of the conductive particles is preferably 0.1% by volume or more, more preferably 1 The volume% or more, preferably 30 volume% or less, more preferably 20 volume% or less.

(Core material) The conductive particles preferably have protrusions on the outer surface of the conductive portion. The conductive particles preferably have protrusions on the conductive surface. The above-mentioned protrusions are preferably plural. An oxide film is formed on the surface of the electrode connected by conductive particles in many cases. In the case of using conductive particles having protrusions on the surface of the conductive portion, the oxide film can be effectively removed by the protrusions by arranging the conductive particles between the electrodes and pressing them together. Therefore, the electrode and the conductive part are in more reliable contact, and the connection resistance between the electrodes is further reduced. Furthermore, when the conductive particles are provided with an insulating material, or when the conductive particles are dispersed in a binder resin and used as a conductive material, the protrusions of the conductive particles can further effectively reduce the conductivity. Eliminate insulating materials or binder resin between particles and electrodes. Therefore, the connection resistance between the electrodes can be further reduced.

When the core material is formed of metal and the core material is present in the conductive part, the core material is regarded as a part of the conductive part.

As a method of forming the above-mentioned protrusions, a method of forming a conductive portion by electroless plating after the core material is attached to the surface of the substrate particle; and forming the conductive portion by electroless plating on the surface of the substrate particle Then, the core material is attached to it, and then the conductive part is formed by electroless plating. Moreover, in order to form the said protrusion, the said core material may not be used.

As another method of forming the above-mentioned protrusions, a method of adding a core material in the middle of forming a conductive portion on the surface of a substrate particle, etc. can be cited. In addition, in order to form the protrusions, the following method may also be used: instead of using the above-mentioned core material, after forming the conductive part by electroless plating on the substrate particles, the plating is deposited on the surface of the conductive part in the form of protrusions, and then by The conductive part is formed by electroless plating.

As a method of attaching the core material to the surface of the substrate particle, there can be mentioned: adding the core material to the dispersion of the substrate particle, and using the Van der Waals force to gather the core material and attach it to the surface of the substrate particle; And the method of adding the core material to the container containing the substrate particle, and attaching the core material to the surface of the substrate particle by the mechanical action generated by the rotation of the container, etc. From the viewpoint of controlling the amount of the core substance attached, the method of attaching the core substance to the surface of the substrate particle is preferably a method of accumulating the core substance and attaching to the surface of the substrate particle in the dispersion.

Examples of the material constituting the core material include conductive materials and non-conductive materials. Examples of the above-mentioned conductive substance include conductive non-metals such as metals, metal oxides, and graphite, and conductive polymers. As said conductive polymer, polyacetylene etc. are mentioned. Examples of the aforementioned non-conductive substance include silica, alumina, and zirconia. From the viewpoint of further effectively removing the oxide film, the above-mentioned core material is preferably harder. From the viewpoint of further effectively reducing the connection resistance between the electrodes, the above-mentioned core material is preferably a metal.

The above metal is not particularly limited. Examples of the above metal include: gold, silver, copper, platinum, zinc, iron, lead, tin, aluminum, cobalt, indium, nickel, chromium, titanium, antimony, bismuth, germanium, and cadmium; and tin-lead alloys , Tin-copper alloy, tin-silver alloy, tin-lead-silver alloy and tungsten carbide alloys containing two or more metals. From the viewpoint of further effectively reducing the connection resistance between the electrodes, the metal is preferably nickel, copper, silver or gold. The metal may be the same as or different from the metal constituting the conductive portion (conductive layer).

The shape of the aforementioned core material is not particularly limited. The shape of the core material is preferably a block shape. Examples of the core material include particulate lumps, agglomerates formed by agglomeration of a plurality of fine particles, and amorphous lumps.

The particle diameter of the above-mentioned core material is preferably 0.001 μm or more, more preferably 0.05 μm or more, preferably 0.9 μm or less, and more preferably 0.2 μm or less. If the particle size of the core material is above the lower limit and below the upper limit, the connection resistance between the electrodes can be further effectively reduced.

The particle diameter of the core material is preferably an average particle diameter, more preferably a number average particle diameter. The particle size of the core material is obtained by observing any 50 core materials with an electron microscope or an optical microscope, and calculating the average value of the particle size of each core material, or using a particle size distribution measuring device. In observation with an electron microscope or an optical microscope, the particle size per core material is calculated as the particle size in terms of equivalent circle diameter. In observation with an electron microscope or an optical microscope, the average particle diameter of any 50 core materials in terms of circle equivalent diameter is approximately equal to the average particle diameter of sphere equivalent diameter. In the particle size distribution measuring device, the particle size per core material is calculated as the particle size based on the equivalent diameter of the sphere. The average particle size of the core material is preferably calculated using a particle size distribution measuring device.

The number of the protrusions per one of the conductive particles is preferably 3 or more, more preferably 5 or more. The upper limit of the number of the aforementioned protrusions is not particularly limited. The upper limit of the number of the above-mentioned protrusions can be appropriately selected in consideration of the particle diameter of the conductive particles and the like. If the number of the protrusions is more than the lower limit, the connection resistance between the electrodes can be further effectively reduced.

The number of the protrusions can be calculated by observing arbitrary conductive particles with an electron microscope or an optical microscope. The number of the above-mentioned protrusions is preferably obtained by observing any 50 conductive particles with an electron microscope or an optical microscope, and calculating the average value of the number of protrusions in each conductive particle.

The height of the protrusions is preferably 0.001 μm or more, more preferably 0.05 μm or more, preferably 0.9 μm or less, and more preferably 0.2 μm or less. If the height of the protrusion is greater than or equal to the aforementioned lower limit and less than the aforementioned upper limit, the connection resistance between the electrodes can be further effectively reduced.

The height of the protrusion can be calculated by observing the protrusion in any conductive particle with an electron microscope or an optical microscope. It is preferable that the height of the said protrusion is calculated as the height of the protrusion of 1 electroconductive particle as the average value of the height of all protrusions per electroconductive particle. It is preferable that the height of the said protrusion is calculated|required by calculating the average value of the height of the protrusion of each electroconductive particle for arbitrary 50 electroconductive particles.

(Insulating substance) The conductive particles preferably include an insulating substance arranged on the outer surface of the conductive portion. In this case, if the above-mentioned conductive particles are used for the connection between the electrodes, the short circuit between adjacent electrodes can be further effectively prevented. Specifically, when a plurality of conductive particles are in contact with each other, an insulating substance exists between the plurality of electrodes, and therefore, it is possible to prevent a short circuit between the electrodes adjacent in the lateral direction rather than between the upper and lower electrodes. In addition, when connecting the electrodes, by pressing the conductive particles with two electrodes, the insulating material between the conductive part of the conductive particles and the electrodes can be easily removed. Furthermore, in the case of conductive particles having protrusions on the outer surface of the conductive part, the insulating material between the conductive part of the conductive particles and the electrode can be removed more easily.

The above-mentioned insulating material is preferably an insulating particle in terms of allowing the above-mentioned insulating material to be removed more easily during pressure bonding between electrodes.

As a material of the said insulating substance, the said organic material, the said inorganic material, and the said inorganic substance etc. mentioned as a material of a base material particle, etc. are mentioned. The material of the insulating substance is preferably the organic material.

Examples of other materials for the above-mentioned insulating material include polyolefin compounds, (meth)acrylate polymers, (meth)acrylate copolymers, block polymers, thermoplastic resins, cross-linked products of thermoplastic resins, and heat Curable resin and water-soluble resin, etc. As for the material of the said insulating substance, only 1 type may be used, and 2 or more types may be used together.

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, polydodecyl (meth)acrylate, polystearyl (meth)acrylate, etc. are mentioned. As the above-mentioned block polymer, polystyrene, styrene-acrylate copolymer, SB (Styrene-Butadiene, styrene-butadiene) type styrene-butadiene block copolymer, and SBS ( Styrene-Butadiene-Styrene, styrene-butadiene-styrene) type styrene-butadiene block copolymer, and its hydrogenated products. As said thermoplastic resin, an ethylene-type polymer, an ethylene-type copolymer, etc. are mentioned. As said thermosetting resin, epoxy resin, phenol resin, melamine resin, etc. are mentioned. Examples of the crosslinked product of the above-mentioned thermoplastic resin include introduction of polyethylene glycol methacrylate, alkoxylated trimethylolpropane methacrylate, alkoxylated pentaerythritol methacrylate, and the like. As said water-soluble resin, polyvinyl alcohol, polyacrylic acid, polyacrylamide, polyvinylpyrrolidone, polyethylene oxide, methyl cellulose, etc. are mentioned. In addition, a chain transfer agent can also be used to adjust the degree of polymerization. As a chain transfer agent, mercaptans, carbon tetrachloride, etc. are mentioned.

As a method of arranging the insulating substance on the surface of the conductive portion, a chemical method, a physical or mechanical method, etc. can be cited. Examples of the above-mentioned chemical method include interfacial polymerization, suspension polymerization in the presence of particles, and emulsion polymerization. Examples of the above-mentioned physical or mechanical methods include spray drying, mixing, electrostatic adhesion, spraying, dipping, and vacuum deposition methods. In the case of electrically connecting electrodes, from the viewpoint of further effectively improving insulation reliability and conduction reliability, the method of arranging the insulating material on the surface of the conductive portion is preferably a physical method.

The outer surface of the conductive portion and the outer surface of the insulating substance 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 substance may be directly chemically bonded, or may be chemically bonded indirectly by a compound having a reactive functional group. After the carboxyl group is introduced to the outer surface of the conductive portion, the carboxyl group may be chemically bonded to the functional group on the outer surface of the insulating material via a polymer electrolyte such as polyethyleneimine.

When the insulating material is an insulating particle, the particle diameter of the insulating particle can be appropriately selected according to the particle diameter of the conductive particle and the purpose of the conductive particle. The particle diameter of the above-mentioned insulating particles is preferably 10 nm or more, more preferably 100 nm or more, still more preferably 300 nm or more, particularly preferably 500 nm or more, preferably 4000 nm or less, more preferably 2000 nm or less, It is more preferably 1500 nm or less, and particularly preferably 1000 nm or less. If the particle diameter of the insulating particles is greater than or equal to the above lower limit, when the conductive particles are dispersed in the binder resin, the conductive portions in the plurality of conductive particles will not easily contact each other. If the particle diameter of the insulating particles is less than the above upper limit, it is not necessary to make the pressure too high when connecting the electrodes, nor to heat to a high temperature to remove the insulating particles between the electrode and the conductive particles.

The particle diameter of the insulating particles is preferably an average particle diameter, and more preferably a number average particle diameter. The particle size of the insulating particles is obtained by observing any 50 insulating particles with an electron microscope or an optical microscope, and calculating the average value of the particle size of each insulating particle, or using a particle size distribution measuring device. In observation with an electron microscope or an optical microscope, the particle diameter per insulating particle is calculated as the particle diameter in terms of the equivalent circle diameter. In observation with an electron microscope or an optical microscope, the average particle diameter in terms of circle equivalent diameter of any 50 insulating particles is approximately the same as the average particle diameter in terms of spherical equivalent diameter. In the particle size distribution measuring device, the particle size per insulating particle is calculated as the particle size based on the equivalent diameter of the sphere. The average particle diameter of the insulating particles is preferably calculated using a particle size distribution measuring device. In the above-mentioned conductive particles, when the particle diameter of the above-mentioned insulating particles is measured, the measurement can be carried out as follows, for example.

The conductive particles were added to "Technovit 4000" manufactured by Kulzer Corporation so that the content was 30% by weight, and dispersed, to prepare embedded resin for conductive particle inspection. The cross section of the conductive particles was cut out using an ion milling device ("IM4000" manufactured by Hitachi High-Technologies) so as to pass the vicinity of the center of the conductive particles dispersed in the embedded resin for inspection. Then, using a field emission scanning electron microscope (FE-SEM), the image magnification was set to 50,000 times, 50 conductive particles were randomly selected, and the insulating particles of each conductive particle were observed. The particle diameter of the insulating particle in each conductive particle is measured, and the arithmetic average of these particles is used as the particle diameter of the insulating particle.

The ratio of the particle diameter of the conductive particles to the particle diameter of the insulating particles (the particle diameter of the conductive particles/the particle diameter of the insulating particles) is preferably 4 or more, more preferably 8 or more, and preferably 200 or less , More preferably 100 or less. If the above ratio (particle size of conductive particles/particle size of insulating particles) is above the above lower limit and below the above upper limit, when the electrodes are electrically connected, the insulation reliability and conduction can be further effectively improved reliability.

(Conductive material) The conductive material of the present invention includes the above-mentioned conductive particles and a binder resin. The above-mentioned conductive particles are preferably dispersed in a binder resin and used, and preferably dispersed in a binder resin and used as a conductive material. The aforementioned conductive material is preferably an anisotropic conductive material. The aforementioned conductive material is preferably used for electrical connection between electrodes. The aforementioned conductive material is preferably a conductive material for circuit connection. In the above-mentioned conductive material, the above-mentioned conductive particles are used. Therefore, the connection resistance between the electrodes can be further effectively reduced, and the occurrence of aggregation of conductive particles can be further effectively suppressed. In the above-mentioned conductive material, the above-mentioned conductive particles are used, and therefore, the insulation reliability between the electrodes can be further effectively improved.

The conductive material preferably includes a plurality of conductive particles. When the region from the outer surface of the substrate particle toward the center that is a distance of 1/2 of the particle diameter of the substrate particle is defined as region R1, in 100% of the total number of the conductive particles, of the substrate particle The ratio of the number of conductive particles in which the conductive metal is present in the region R1 (hereinafter, sometimes referred to as the first ratio) is preferably 50% or more, and more preferably 60% or more. The upper limit of the above-mentioned first ratio is not particularly limited. The aforementioned first ratio may be 100% or less. If the said 1st ratio is more than the said lower limit, the connection resistance between electrodes can be reduced more effectively, and the generation of aggregation of conductive particles can be suppressed more effectively. In addition, if the first ratio is greater than or equal to the lower limit, the insulation reliability between the electrodes can be further effectively improved. In addition, if the first ratio is greater than or equal to the lower limit and less than the upper limit, the adhesion of the conductive part in the conductive particle can be further effectively improved, and the occurrence of peeling of the conductive part in the conductive particle can be further effectively suppressed . If the above-mentioned first ratio exceeds 0%, it can be judged that a conductive metal is contained inside the substrate particles. The above-mentioned region R1 is a region on the outer side of the broken line L1 of the base particle 2 in FIG. 4. The region R1 is an outer surface portion of the substrate particle. The region R1 is a region different from the central part of the substrate particle.

When the region from the center of the substrate particle toward the outer surface that is a distance of 1/2 of the particle diameter of the substrate particle is defined as the region R2, in 100% of the total number of the conductive particles, of the substrate particle The ratio of the number of conductive particles in which the conductive metal is present in the region R2 (hereinafter, may be referred to as the second ratio) is preferably 5% or more, more preferably 10% or more. The upper limit of the above-mentioned second ratio is not particularly limited. The aforementioned second ratio may be 100% or less. If the second ratio is greater than or equal to the lower limit, the connection resistance between the electrodes can be reduced more effectively, and the occurrence of aggregation of conductive particles can be more effectively suppressed. In addition, if the second ratio is greater than or equal to the lower limit, the insulation reliability between the electrodes can be further effectively improved. In addition, if the second ratio is greater than or equal to the above lower limit and less than or equal to the above upper limit, the adhesion of the conductive portion in the conductive particle can be further effectively improved, and the occurrence of peeling of the conductive portion in the conductive particle can be further effectively suppressed . If the above-mentioned second ratio exceeds 0%, it can be judged that the substrate particle contains a conductive metal. The above-mentioned region R2 is a region on the inner side of the dotted line L1 of the base particle 2 in FIG. 4. The region R2 is the central part of the substrate particle. The region R2 is a region different from the outer surface portion of the substrate particle.

The first ratio and the second ratio can be calculated as follows.

The conductive particles are recovered from the conductive material by filtration or the like. The collected conductive particles were added to "Technovit 4000" manufactured by Kulzer Corporation so that the content of the conductive particles became 30% by weight, and dispersed to prepare embedded resin for conductive particle inspection. An ion milling device ("IM4000" manufactured by Hitachi High-Technologies) was used to cut out a cross section of one conductive particle by passing the vicinity of the center of the conductive particle dispersed in the embedded resin for inspection. Then, using a field emission type transmission electron microscope ("JEM-2010FEF" manufactured by JEOL Ltd.), the presence or absence of conductive metal on the cross section of the substrate particle was measured by an energy dispersive X-ray analyzer (EDS), In this way, the distribution result of the conductive metal in the particle size direction of the substrate particles is obtained. The above-mentioned first ratio and the above-mentioned second ratio can be calculated from the distribution result of the conductive metal in 20 arbitrarily selected conductive particles.

The above-mentioned binder resin is not particularly limited. As the above-mentioned binder resin, a known insulating resin is used. The aforementioned 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. The above-mentioned photocurable component preferably contains a photocurable compound and a photopolymerization initiator. It is preferable that the said thermosetting component contains a thermosetting compound and a thermosetting agent.

Examples of the above-mentioned binder resin include vinyl resins, thermoplastic resins, curable resins, thermoplastic block copolymers, and elastomers. The said binder resin may use only 1 type, and may use 2 or more types together.

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

In addition to the conductive particles and the binder resin, the conductive material may also include, for example, fillers, extenders, softeners, plasticizers, polymerization catalysts, hardening catalysts, colorants, antioxidants, and heat stabilizers. , Light stabilizers, UV absorbers, lubricants, antistatic agents and flame retardants and other additives.

The method for dispersing the conductive particles in the binder resin can use a conventionally known dispersion method, and is not particularly limited. As a method of dispersing the conductive particles in the binder resin, the following methods and the like can be cited. A method of adding the above-mentioned conductive particles to the above-mentioned binder resin, and then kneading and dispersing them with a planetary mixer. A method of uniformly dispersing the conductive particles in water or an organic solvent using a homogenizer or the like, adding them to the binder resin, and kneading and dispersing them using a planetary mixer or the like. A method of diluting the above-mentioned binder resin with water, an organic solvent, etc., adding the above-mentioned conductive particles, and kneading and dispersing them with a planetary mixer or the like.

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

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

The conductive material of the present invention can be used as conductive paste and conductive film. When the conductive material of the present invention is a conductive film, a film that does not include conductive particles may be laminated on the conductive film including conductive particles. The aforementioned conductive paste is preferably an 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 10% by weight or more, more preferably 30% by weight or more, still more preferably 50% by weight or more, particularly preferably 70% by weight or more, and more preferably 99.99% by weight or less, more preferably 99.9% by weight or less. If the content of the binder resin is greater than or equal to the aforementioned lower limit and less than or equal to the aforementioned upper limit, conductive particles can be efficiently arranged between the electrodes, and the connection reliability of the connection target member connected by the conductive material can be further improved.

In 100% by weight of the conductive material, the content of the conductive particles is preferably 0.01% by weight or more, more preferably 0.1% by weight or more, preferably 80% by weight or less, more preferably 60% by weight or less, and still more preferably 40% by weight or less, particularly preferably 20% by weight or less, and most preferably 10% by weight or less. If the content of the conductive particles is greater than or equal to the aforementioned lower limit and less than or equal to the aforementioned upper limit, the connection resistance between electrodes can be further effectively reduced. If the content of the conductive particles is greater than or equal to the aforementioned lower limit and less than or equal to the aforementioned upper limit, the reliability of conduction and insulation between electrodes can be further improved.

(Connected structure) The connection structure of the present invention includes: a first connection object member having a first electrode on the surface; a second connection object member having a second electrode on the surface; and a connection portion that connects the first connection object member and the The second connection object member is connected. In the connection structure of the present invention, the material of the connection portion is the conductive particles, or a conductive material containing the conductive particles and a binder resin. In the connection structure of the present invention, the first electrode and the second electrode are electrically connected by the conductive particles.

The connection structure can be obtained by the steps of arranging the conductive particles or the conductive material between the first connection object member and the second connection object member, and conductive connection by thermal compression bonding step. When the conductive particles have the insulating material, it is preferable that the insulating material is detached from the conductive particles during the thermocompression bonding.

When the above-mentioned conductive particles are used alone, the connection portion itself is conductive particles. That is, the said 1st connection object member and the said 2nd connection object member are connected by the said electroconductive particle. The conductive material used to obtain the connection structure is preferably an anisotropic conductive material.

Fig. 5 schematically shows a front cross-sectional view of a connected structure using conductive particles according to the first embodiment of the present invention.

The connection structure 51 shown in FIG. 5 includes a first connection object member 52, a second connection object member 53, and a connection portion 54 that connects the first and second connection object members 52 and 53. The connection portion 54 is formed by curing a conductive material containing the conductive particles 1. In addition, in FIG. 5, the electroconductive particle 1 is shown as a schematic diagram for the convenience of illustration. Instead of the conductive particles 1, other conductive particles such as the conductive particles 11 and 21 may be used.

The first connection object member 52 has a plurality of first electrodes 52a on the surface (upper surface). The second connection object member 53 has a plurality of second electrodes 53a on the surface (lower surface). The first electrode 52a and the second electrode 53a are electrically connected by one or more conductive particles 1. Therefore, the first and second connection target members 52 and 53 are electrically connected by the conductive particles 1.

The manufacturing method of the said connection structure is not specifically limited. As an example of the manufacturing method of the connection structure, the following method can be cited: the conductive material is arranged between the first connection object member and the second connection object member to obtain a laminate, and then the laminate is heated and pressurized . The pressure of the above-mentioned thermocompression bonding is preferably 40 MPa or more, more preferably 60 MPa or more, preferably 90 MPa or less, and more preferably 70 MPa or less. The heating temperature of the thermal compression bonding is preferably 80°C or higher, more preferably 100°C or higher, preferably 140°C or lower, and more preferably 120°C or lower. If the pressure and temperature of the thermocompression bonding are above the above lower limit and below the above upper limit, the reliability of conduction and insulation between the electrodes can be further improved. In addition, when the conductive particles have the insulating particles, the insulating particles can be easily detached from the surface of the conductive particles during conductive connection.

When the conductive particles have the insulating particles, when the laminate is heated and pressurized, the conductive particles and the insulating particles existing between the first electrode and the second electrode may be combined exclude. For example, when the heating and pressurization are performed, the conductive particles and the insulating particles existing between the first electrode and the second electrode are easily detached from the surface of the conductive particles. Furthermore, during the heating and pressurization, a part of the insulating particles may be detached from the surface of the conductive particle, and the surface of the conductive portion may be partially exposed. By contacting the exposed portion of the surface of the conductive portion with the first electrode and the second electrode, the first electrode and the second electrode can be electrically connected via the conductive particles.

Furthermore, in the connection structure of the present invention, since the conductive particles are used, the conductive particles are compressed during the heating and pressurization, thereby forming a conductive path not only on the surface (conductive portion) of the conductive particles , And the conductive metals inside the conductive particles contact each other, thereby forming a conductive path. As a result, even when the thickness of the conductive portion is relatively thin, the connection resistance between the electrodes in the vertical direction can be sufficiently reduced. In addition, since the thickness of the conductive portion is relatively thin, the occurrence of aggregation of conductive particles can be suppressed, and the insulation reliability between adjacent electrodes in the lateral direction that should not be connected can be effectively improved.

The above-mentioned first connection target member and second connection target member are not particularly limited. Specific examples of the first connection target member and the second connection target member include semiconductor wafers, semiconductor packages, LED (Light Emitting Diode) wafers, LED packages, capacitors, and diodes. Electronic parts such as resin films, printed circuit boards, flexible printed circuit boards, flexible flat cables, rigid flexible substrates, glass epoxy substrates, and circuit boards such as glass substrates. The first connection target member and the second connection target member are preferably electronic components.

Examples of the electrode provided on the connection target member include metal electrodes such as gold electrodes, nickel electrodes, tin electrodes, aluminum electrodes, copper electrodes, molybdenum electrodes, silver electrodes, SUS (Steel Use Stainless) electrodes, and tungsten electrodes. When the connection object member 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 connection object member is a glass substrate, the electrode is preferably an aluminum electrode, a copper electrode, a molybdenum electrode, a silver electrode, or a tungsten electrode. Furthermore, when the above-mentioned electrode is an aluminum electrode, it may be an electrode formed only of aluminum, or an electrode with an aluminum layer on the surface area of the metal oxide layer. As the material of the metal oxide layer, indium oxide doped with trivalent metal element, zinc oxide doped with trivalent metal element, and the like can be cited. As said trivalent metal element, Sn, Al, Ga, etc. are mentioned.

Hereinafter, examples and comparative examples are given to specifically describe the present invention. The present invention is not limited to the following examples.

(Example 1) (1) Production of substrate particles Prepare polystyrene particles with an average particle diameter of 0.5 μm as seed particles. 3.9 parts by weight of the above-mentioned polystyrene particles, 500 parts by weight of ion-exchange water, and 120 parts by weight of 5% by weight polyvinyl alcohol aqueous solution were mixed to prepare a mixed solution. After dispersing the above-mentioned mixed liquid by ultrasonic waves, it is placed in a separable flask and stirred uniformly.

Next, 150 parts by weight of divinylbenzene (monomer component), 2 parts by weight of 2,2'-azobis(methyl isobutyrate) ("V-601" manufactured by Wako Pure Chemical Industries, Ltd.), and 2 parts by weight of benzoyl oxide ("Nyper BW" manufactured by NOF Corporation) were mixed. Furthermore, 9 parts by weight of triethanolamine lauryl sulfate, 50 parts by weight of toluene (solvent), and 1,100 parts by weight of ion-exchange water were added to prepare an emulsion.

Add the emulsified liquid to the mixed liquid in the separable flask several times and stir for 12 hours to allow the seed particles to absorb the monomer to obtain a suspension containing the seed particles swelled by the monomer.

After that, 490 parts by weight of a 5 wt% polyvinyl alcohol aqueous solution was added, heating was started, and the reaction was performed at 85° C. for 9 hours to obtain substrate particles with a particle diameter of 2.0 μm.

(2) Production of conductive particles After the obtained substrate particles are washed and dried, 10 parts by weight of the substrate particles are dispersed in 1000 parts by weight of an alkaline solution containing 5% by weight palladium catalyst solution using an ultrasonic disperser, and then the solution is filtered. This takes out the substrate particles. Then, the substrate particles are added to 100 parts by weight of the dimethylamine borane 1% by weight solution to activate the surface of the substrate particles. After sufficiently washing the surface of the substrate particles with activated water, they were added to 500 parts by weight of distilled water and dispersed to obtain a dispersion. Next, it took 3 minutes to add 1 g of the nickel particle slurry (average particle size 100 nm) to the above dispersion to obtain a suspension containing the substrate particles with the core material attached.

Also, prepare 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.

While stirring the obtained suspension at 60°C, 300 parts by weight of the above-mentioned nickel plating solution was gradually dropped into the suspension to perform electroless nickel plating. Thereafter, by filtering the suspension, the particles are taken out, washed with water, and dried, thereby forming a nickel-boron conductive layer on the surface of the substrate particles, thereby obtaining conductive particles having conductive portions on the surface.

(3) Production of conductive materials (anisotropic conductive paste) 7 parts by weight of the obtained conductive particles, 25 parts by weight of bisphenol A type phenoxy resin, 4 parts by weight of sulphur type epoxy resin, 30 parts by weight of phenol novolak type epoxy resin, and SI-60L (three New Chemical Industry Co., Ltd.) was mixed together, defoamed and stirred for 3 minutes to obtain a conductive material (anisotropic conductive paste).

(4) Production of connecting structure Prepare a transparent glass substrate with an IZO (Indium Zinc Oxide) electrode pattern with an L/S of 10 μm/10 μm (the first electrode, the Vickers hardness of the metal on the electrode surface is 100 Hv) formed on the upper surface. Also, prepare a semiconductor wafer in which an Au electrode pattern (the second electrode, the Vickers hardness of the metal on the electrode surface is 50 Hv) with an L/S of 10 μm/10 μm is formed on the bottom surface. On the above-mentioned transparent glass substrate, the obtained anisotropic conductive paste was applied so that the thickness became 30 μm to form an anisotropic conductive paste layer. Next, the semiconductor wafer is laminated on the anisotropic conductive paste layer so that the electrodes face each other. After that, while adjusting the temperature of the head so that the temperature of the anisotropic conductive paste layer becomes 100°C, a pressure heating head is placed on the upper surface of the semiconductor wafer, and a pressure of 85 MPa is applied at 100°C to make the anisotropy The conductive paste layer is hardened to obtain a connection structure.

(Example 2) When the substrate particles were produced, except that the blending amount of the solvent was 10 parts by weight, the same procedure as in Example 1 was carried out to obtain conductive particles, a conductive material, and a connection structure.

(Example 3) When the base particles were produced, except that the blending amount of the solvent was 70 parts by weight, the same procedure as in Example 1 was carried out to obtain conductive particles, a conductive material, and a connection structure.

(Example 4) When producing conductive particles, except that the blending amount of the substrate particles was 5 parts by weight, the same procedure as in Example 1 was carried out to obtain a conductive material and a connection structure.

(Example 5) When producing conductive particles, except that the blending amount of the substrate particles was 2.5 parts by weight, the same procedure as in Example 1 was carried out to obtain a conductive material and a connection structure.

(Example 6) The conductive particles obtained in Example 1 were prepared. Furthermore, 5 g of potassium gold cyanide was added to 500 g of a solution containing 10 g/L sodium ethylenediaminetetraacetate and 10 g/L sodium citrate to prepare a gold plating solution. 10 parts by weight of the conductive particles obtained in Example 1 were put into 500 parts by weight of the gold plating solution and immersed at 70° C. for 30 minutes to perform electroless gold plating. After that, by filtering the suspension, the particles are taken out, washed with water, and dried, thereby forming a nickel-boron-gold conductive layer on the surface of the substrate particles, thereby obtaining conductive particles having conductive portions on the surface. Except having used the obtained electroconductive particle, it carried out similarly to Example 1, and obtained the electroconductive material and connection structure.

(Example 7) 10 parts by weight of the conductive particles obtained in Example 1 were added to 200 parts by weight of distilled water and dispersed to obtain a suspension. In addition, prepare a palladium plating solution containing 10 g/L ethylenediamine, 3.0 g/L palladium sulfate, and 5.0 g/L sodium formate. After heating the suspension to 70°C, 700 parts by weight of the palladium plating solution was dropped over 10 minutes to perform electroless palladium plating. Thereafter, by filtering the suspension, the particles are taken out, washed with water, and dried, thereby forming a nickel-boron-palladium conductive layer on the surface of the substrate particles, thereby obtaining conductive particles having conductive portions on the surface. Except having used the obtained electroconductive particle, it carried out similarly to Example 1, and obtained the electroconductive material and connection structure.

(Example 8) 10 parts by weight of the conductive particles obtained in Example 1 were added to 200 parts by weight of distilled water and dispersed to obtain a suspension. In addition, prepare a silver plating solution, which will contain 10 g/L potassium silver cyanide, 80 g/L potassium cyanide, 5 g/L ethylenediaminetetraacetic acid, and 20 g/L using sodium hydroxide. Adjust the pH of the sodium hydroxide mixture to 6. After heating the suspension to 50°C, 700 parts by weight of the silver plating solution was dropped over 30 minutes to perform electroless silver plating. Thereafter, by filtering the suspension, the particles are taken out, washed with water, and dried, thereby forming a nickel-boron-silver conductive layer on the surface of the substrate particle, thereby obtaining conductive particles having conductive portions on the surface. Except having used the obtained electroconductive particle, it carried out similarly to Example 1, and obtained the electroconductive material and connection structure.

(Example 9) When producing the substrate particles, by changing the seed particle diameter, substrate particles with a particle diameter of 1.0 μm are obtained. Except having used the obtained substrate particle and changing the addition amount of the obtained substrate particle to 5 weight part, it carried out similarly to Example 1, and obtained electroconductive particle, a conductive material, and a connection structure.

(Example 10) When producing the substrate particles, by changing the seed particle diameter, substrate particles with a particle diameter of 2.5 μm are obtained. Except having used the obtained substrate particles and changing the addition amount of the obtained substrate particles to 12.5 parts by weight, the same procedure as in Example 1 was carried out to obtain conductive particles, a conductive material, and a connection structure.

(Example 11) When producing the substrate particles, by changing the seed particle diameter, substrate particles with a particle diameter of 3.0 μm are obtained. Except having used the obtained substrate particles and changing the addition amount of the obtained substrate particles to 15 parts by weight, the same procedure as in Example 1 was carried out to obtain conductive particles, a conductive material, and a connection structure.

(Example 12) When the substrate particles were produced, the diameter of the seed particles was changed to obtain substrate particles with a particle diameter of 5.0 μm. Except having used the obtained substrate particles and changing the addition amount of the obtained substrate particles to 25 parts by weight, the same procedure as in Example 1 was carried out to obtain conductive particles, a conductive material, and a connection structure.

(Example 13) When the substrate particles were produced, the diameter of the seed particles was changed to obtain substrate particles with a particle diameter of 10.0 μm. Except having used the obtained substrate particles and changing the addition amount of the obtained substrate particles to 50 parts by weight, the same procedure as in Example 1 was carried out to obtain conductive particles, a conductive material, and a connection structure.

(Example 14) (1) Production of insulating particles After adding the following monomer composition to a 1000 mL separable flask equipped with a four-port separable cap, stirring blade, three-way cock, cooling tube and temperature probe, the solid component of the following monomer composition Distilled water was put in so as to be 10% by weight, stirred at 200 rpm, and polymerization was performed at 60°C for 24 hours in a nitrogen atmosphere. The above-mentioned monomer composition comprises 360 mmol of methyl methacrylate, 45 mmol of glycidyl methacrylate, 20 mmol of p-styryl diethyl phosphine, 13 mmol of ethylene glycol dimethacrylate, and polyvinylpyrrolidone 0.5 mmol, and 2,2'-azobis{2-[N-(2-carboxyethyl)amidino]propane} 1 mmol. After completion of the reaction, it was freeze-dried to obtain insulating particles (particle size 360 nm) having phosphorus atoms derived from p-styryl diethyl phosphine on the surface.

(2) Production of conductive particles with insulating particles The insulating particles obtained in (1) above were dispersed in distilled water under ultrasonic irradiation to obtain a 10% by weight aqueous dispersion of insulating particles. 10 g of the conductive particles obtained in Example 1 were dispersed in 500 mL of distilled water, and 1 g of a 10% by weight aqueous dispersion of insulating particles was added, and the mixture was stirred at room temperature for 8 hours. After filtering with a 3 μm mesh filter, it was further washed with methanol and dried to obtain conductive particles with insulating particles. A conductive material and a connection structure were obtained in the same manner as in Example 1 except that the obtained conductive particles with insulating particles were used.

(Example 15) When producing conductive particles, except that the nickel particle slurry (average particle diameter 100 nm) was not used, the same procedure as in Example 1 was carried out to obtain conductive particles, a conductive material, and a connection structure.

(Example 16) When producing conductive particles, except that the amount of the catalyst liquid was changed to 200 parts by weight, the same procedure as in Example 1 was carried out to obtain conductive particles, a conductive material, and a connection structure.

(Example 17) When producing conductive particles, except that the amount of the catalyst liquid was changed to 500 parts by weight, in the same manner as in Example 1, conductive particles, conductive materials, and connection structures were obtained.

(Example 18) The conductive particles obtained in Example 15 were prepared. Using the conductive particles obtained in Example 15, conductive particles with insulating particles were obtained in the same manner as in Example 14. A conductive material and a connection structure were obtained in the same manner as in Example 1 except that the obtained conductive particles with insulating particles were used.

(Comparative example 1) When the substrate particles were produced, except that the solvent was changed from toluene to ethanol, in the same manner as in Example 1, conductive particles, conductive materials, and connection structures were obtained.

(Comparative example 2) When producing conductive particles, except that the blending amount of the base particles was 5 parts by weight, the same procedure as in Comparative Example 1 was carried out to obtain conductive particles, a conductive material, and a connection structure.

(Comparative example 3) The conductive particles obtained in Comparative Example 2 were prepared. Using the conductive particles obtained in Comparative Example 2, in the same manner as in Example 14, conductive particles with insulating particles were obtained. A conductive material and a connection structure were obtained in the same manner as in Example 1 except that the obtained conductive particles with insulating particles were used.

(Comparative Example 4) When producing conductive particles, except that the blending amount of the substrate particles was 20 parts by weight, the same procedure as in Comparative Example 1 was carried out to obtain conductive particles, a conductive material, and a connection structure.

(Evaluation) (1) Particle size of substrate particles and conductive particles With respect to the obtained substrate particles and conductive particles, the particle diameters of the substrate particles and conductive particles were calculated using a particle size distribution measuring device ("Multisizer 4" manufactured by Beckman Coulter). Specifically, it is determined by measuring the particle size of approximately 100,000 substrate particles or conductive particles, and calculating the average value.

(2) BET specific surface area of substrate particles For the obtained substrate particles, the nitrogen adsorption isotherm was measured using "NOVA4200e" manufactured by Quantachrome Instruments. According to the BET method, the specific surface area of the substrate particles is calculated from the measurement results.

(3) Total pore volume of substrate particles With respect to the obtained substrate particles, the adsorption isotherm of nitrogen was measured using "NOVA4200e" of Quantachrome Instruments. According to the BJH method, the total pore volume of the substrate particles is calculated from the measurement results.

(4) Average pore diameter of substrate particles With respect to the obtained substrate particles, the adsorption isotherm of nitrogen was measured using "NOVA4200e" of Quantachrome Instruments. According to the BJH method, the total pore volume of the substrate particles is calculated from the measurement results.

(5) Porosity of substrate particles For the obtained substrate particles, a mercury porosimeter "PoreMaster 60" manufactured by Quantachrome Instruments was used to measure the cumulative infiltration amount of mercury relative to the pressure applied by the mercury permeation method. From the measurement results, the porosity of the substrate particles was calculated.

(6) The content of conductive metal in 100% by volume of conductive particles For the obtained conductive particles, the content of the conductive metal in 100% by volume of the conductive particles was calculated as follows.

The content of conductive metal in 100% by volume of conductive particles (vol%) = D×M/Dmetal×100 D: Specific gravity of conductive particles M: Metallization rate of conductive particles Dmetal: Specific gravity of conductive metal

In addition, the metallization rate of the conductive particles was calculated using an ICP emission analyzer ("ICP-AES" manufactured by Horiba Manufacturing Co., Ltd.). The specific gravity of the conductive particles was measured using a true hydrometer ("AccuPyc" manufactured by Shimadzu Corporation). In addition, the specific gravity of the conductive metal is calculated using the value inherent to the metal.

(7) The content of the conductive metal contained in the substrate particle in 100% by volume of the conductive particles and the content of the conductive metal contained in the conductive part in 100% by volume of the conductive particles For the obtained conductive particles, the content of the conductive metal contained in the conductive portion in 100% by volume of the conductive particles was calculated as follows.

The content of the conductive metal contained in the conductive part in 100% by volume of the conductive particles (vol%) = D×M ₁ /Dmetal×100 M ₁ : Metallization rate of the conductive part Dmetal: Specific gravity of the conductive metal

Furthermore, the metallization rate M _{1 of the} conductive part refers to the ratio of the content (g) of the conductive metal contained in the conductive part contained in the conductive particle 1 g, that is, it is the ratio expressed in 1 g of the conductive particle The content of the conductive metal in the conductive part contained (g)/conductive particle 1 g.

In addition, the metallization ratio M ₁ of the conductive part is calculated using the following two relational expressions. A=[(r＋t) ³ －r ³ ]d ₁ /r ³ d ₂ (1) A=M ₁ /(1－M ₁ ) (2) r: radius of substrate particle t: thickness of conductive part d ₁ : Specific gravity of conductive metal d ₂ : Specific gravity of substrate particles M ₁ : Metallization rate of conductive part

Next, with respect to the obtained conductive particles, the content of the conductive metal contained in the base particles in 100% by volume of the conductive particles is calculated as follows.

The content of the conductive metal contained in the substrate particles in 100% by volume of the conductive particles (vol%) = the content of the conductive metal in 100% by volume of the conductive particles (% by volume)-100% by volume of the conductive particles The content of the conductive metal contained in the conductive part (vol%) = D×M/Dmetal×100－D×M ₁ /Dmetal×100=D×(M－M ₁ )/Dmetal×100 D: conductivity Specific gravity of particles M: Metallization rate of conductive particles M ₁ : Metallization rate of conductive parts Dmetal: Specific gravity of conductive metal

(8) The ratio of the number of conductive particles with conductive metal (the first ratio and the second ratio) When the obtained conductive material is used and the region from the outer surface of the substrate particle toward the center that is a distance of 1/2 of the particle diameter of the substrate particle as the region R1, the total of the conductive particles is calculated as follows The ratio of the number of conductive particles of the conductive metal present in the region R1 of the substrate particles in the number of 100% (first ratio). Also, when the obtained conductive material is used, and the region from the center of the substrate particle toward the outer surface that is a distance of 1/2 of the particle diameter of the substrate particle as the region R2, the conductive particle is calculated as follows The ratio of the number of conductive particles of the conductive metal present in the region R2 of the substrate particles in 100% of the total number (the second ratio).

The conductive particles are collected by filtering the obtained conductive material. It was added to "Technovit 4000" manufactured by Kulzer Corporation so that the content of the recovered conductive particles became 30% by weight, and dispersed to prepare embedded resin for conductive particle inspection. An ion milling device ("IM4000" manufactured by Hitachi High-Technologies) was used to cut out a cross section of one conductive particle by passing the vicinity of the center of the conductive particle dispersed in the embedded resin for inspection. Then, using a field emission type transmission electron microscope ("JEM-2010FEF" manufactured by JEOL Ltd.), the presence or absence of conductive metal on the cross section of the substrate particle was measured by an energy dispersive X-ray analyzer (EDS), In this way, the distribution result of the conductive metal in the particle size direction of the substrate particles is obtained. The above-mentioned first ratio and the above-mentioned second ratio are calculated from the distribution result of the conductive metal in 20 arbitrarily selected conductive particles.

(9) Compression modulus of conductive particles For the obtained conductive particles, the above-mentioned compression modulus (10% K value and 30% K value) was measured using a micro compression tester ("Fischerscope H-100" manufactured by Fischer Corporation) by the above method. Calculate the 10% K value and 30% K value from the measurement results.

(10) Aggregation of conductive particles Observe the obtained conductive material to confirm whether agglomeration of conductive particles has occurred. The aggregation of conductive particles was judged under the following conditions.

[Criteria for judging the aggregation of conductive particles] ○: No aggregation of conductive particles occurred △: Aggregation of conductive particles slightly occurred ×: Aggregation of conductive particles has occurred

(11) Adhesion of conductive parts in conductive particles Put 1.0 g of the obtained conductive particles and 50 g of zirconia beads with a diameter of 1 mm into a 100 mL mayonnaise bottle. Furthermore, 10 mL of toluene was added to the mayonnaise bottle. Use a blender (Trinity Motor) to stir in the mayonnaise bottle at 300 rpm for 10 minutes. After stirring, the conductive particles and the zirconia beads were classified, and the conductive particles were observed using a scanning electron microscope (SEM) to confirm whether or not the conductive part in the conductive particles peeled off. The adhesion of the conductive part in the conductive particle was judged under the following conditions.

[Criteria for judging the adhesion of conductive parts in conductive particles] ○: The conductive part of the conductive particles did not peel off ×: The conductive part of the conductive particles peeled off

(12) Connection resistance (between upper and lower electrodes) The connection resistance between the upper and lower electrodes of the 20 connection structures obtained was measured by the four-terminal method. Calculate the average value of the connection resistance. Furthermore, the connection resistance can be obtained from the relationship of voltage=current×resistance by measuring the voltage when a certain current flows. Determine the connection resistance based on the following criteria.

[Judgment criteria for connected resistance] ○○○: The average value of the connection resistance is 1.5 Ω or less ○ ○: The average value of the connection resistance exceeds 1.5 Ω and is 2.0 Ω or less ○: The average value of the connection resistance exceeds 2.0 Ω and is below 5.0 Ω △: The average value of connection resistance exceeds 5.0 Ω and is less than 10 Ω ×: The average value of connection resistance exceeds 10 Ω

(13) Insulation reliability (between adjacent electrodes in the lateral direction) Regarding the 20 connection structures obtained in the above-mentioned (12) connection reliability evaluation, the resistance value was measured with a tester to evaluate the presence or absence of leakage between adjacent electrodes. The insulation reliability was evaluated based on the following criteria.

[Criteria for Insulation Reliability] ○○○: The number of connection structures with a resistance value of 10 ⁸ Ω or more is 20 ○ ○: The number of connection structures with a resistance value of 10 ⁸ Ω or more is 18 or more And less than 20 ○: The number of connected structures with a resistance of 10 ⁸ Ω or more is 15 or more and less than 18 △: The number of connected structures with a resistance of 10 ⁸ Ω or more is 10 or more And less than 15 ×: The number of connected structures with a resistance value of 10 ⁸ Ω or more is less than 10

The results are shown in Tables 1 to 4 below.

[Table 1] Example 1 Example 2 Example 3 Example 4 Example 5 Substrate particles Particle size (μm) 2.0 2.0 2.0 2.0 2.0 BET specific surface area (m ² /g) 310 95 490 310 310 Total pore volume (cm ³ /g) 0.26 0.15 0.58 0.26 0.26 Average pore size (nm) 2.1 1.5 4.2 2.1 2.1 Porosity (%) 33 11 55 33 33 Conductive particles Prominence Have Have Have Have Have Existence of insulating material no no no no no Conductive part Ni-B Ni-B Ni-B Ni-B Ni-B Thickness of conductive part (nm) 52 85 30 70 85 Particle size (μm) 2.1 2.2 2.1 2.1 2.3 10%K value (N/mm ² ) 6250 8840 13830 9830 12500 30%K value (N/mm ² ) 3950 4920 8660 4220 7520 10%K value/30%K value 1.58 1.80 1.60 2.33 1.66 The content of conductive metal in 100% by volume of conductive particles (vol%) 35 34 35 32 35 The content of the conductive metal contained in the base particles in 100% by volume of the conductive particles (vol%) 15 twenty three 10 18 20 The content of conductive metal contained in the conductive part in 100% by volume of conductive particles (vol%) 20 11 25 14 15 The first ratio (%) 80 55 80 65 70 The second ratio (%) 40 20 80 75 50 Cohesion ○ ○ ○ ○ ○ Adhesion of conductive part ○ ○ ○ ○ ○ Connection structure Connection resistance ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Insulation reliability ○ ○ ○ ○ ○ ○ ○ ○ ○

[Table 2] Example 6 Example 7 Example 8 Example 9 Example 10 Substrate particles Particle size (μm) 2.0 2.0 2.0 1.0 2.5 BET specific surface area (m ² /g) 310 310 310 320 330 Total pore volume (cm ³ /g) 0.26 0.26 0.26 0.32 0.27 Average pore size (nm) 2.1 2.1 2.1 2.3 2.5 Porosity (%) 33 33 33 36 34 Conductive particles Prominence Have Have Have Have Have Existence of insulating material no no no no no Conductive part Ni/Au Ni/Pd Ni/Ag Ni-B Ni-B Thickness of conductive part (nm) 55 65 65 52 53 Particle size (μm) 2.2 2.2 2.2 1.2 2.6 10%K value (N/mm ² ) 6530 7560 8520 13530 4320 30%K value (N/mm ² ) 3750 4050 5220 6530 2400 10%K value/30%K value 1.74 1.87 1.63 2.07 1.80 The content of conductive metal in 100% by volume of conductive particles (vol%) 33 33 32 45 34 The content of the conductive metal contained in the base particles in 100% by volume of the conductive particles (vol%) 15 16 16 20 17 The content of conductive metal contained in the conductive part in 100% by volume of conductive particles (vol%) 18 17 16 25 17 The first ratio (%) 75 80 85 85 80 The second ratio (%) 60 65 55 80 60 Cohesion ○ ○ ○ ○ ○ Adhesion of conductive part ○ ○ ○ ○ ○ Connection structure Connection resistance ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Insulation reliability ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

[table 3] Example 11 Example 12 Example 13 Example 14 Example 15 Example 16 Substrate particles Particle size (μm) 3.0 5.0 10.0 2.0 2.0 2.0 BET specific surface area (m ² /g) 315 320 330 310 310 310 Total pore volume (cm ³ /g) 0.28 0.32 0.35 0.26 0.26 0.26 Average pore size (nm) 2.3 2.5 2.4 2.1 2.1 2.1 Porosity (%) 33 31 33 33 33 33 Conductive particles Prominence Have Have Have Have no Have Existence of insulating material no no no Have no no Conductive part Ni-B Ni-B Ni-B Ni-B Ni-B Ni-B Thickness of conductive part (nm) 53 55 52 52 52 105 Particle size (μm) 3.1 5.2 10.2 2.2 2.2 2.1 10%K value (N/mm ² ) 6530 4200 1580 6320 5520 4720 30%K value (N/mm ² ) 2780 2350 750 3850 3250 1150 10%K value/30%K value 2.35 1.79 2.11 1.64 1.70 4.10 The content of conductive metal in 100% by volume of conductive particles (vol%) twenty three 18 13 35 30 35 The content of the conductive metal contained in the base particles in 100% by volume of the conductive particles (vol%) 15 13 11 17 17 26 The content of conductive metal contained in the conductive part in 100% by volume of conductive particles (vol%) 8 5 2 18 13 9 The first ratio (%) 60 80 80 65 70 90 The second ratio (%) 30 20 15 35 40 10 Cohesion ○ ○ ○ ○ ○ ○ Adhesion of conductive part ○ ○ ○ ○ ○ ○ Connection structure Connection resistance ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Insulation reliability ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○

[Table 4] Example 17 Example 18 Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Substrate particles Particle size (μm) 2.0 2.0 2.0 2.0 2.0 2.0 BET specific surface area (m ² /g) 310 310 1.8 1.8 1.8 1.8 Total pore volume (cm ³ /g) 0.26 0.26 0 0 0 0 Average pore size (nm) 2.1 2.1 0 0 0 0 Porosity (%) 33 33 0 0 0 0 Conductive particles Prominence Have no Have Have Have Have Existence of insulating material no Have no no Have no Conductive part Ni-B Ni-B Ni-B Ni-B Ni-B Ni-B Thickness of conductive part (nm) 85 52 150 300 300 75 Particle size (μm) 2.1 2.2 2.3 2.6 2.6 2.1 10%K value (N/mm ² ) 5380 5520 12500 12550 13,600 10320 30%K value (N/mm ² ) 1710 3050 9790 9730 10280 7850 10%K value/30%K value 3.15 1.81 1.28 1.29 1.32 1.31 The content of conductive metal in 100% by volume of conductive particles (vol%) 35 35 33 35 36 34 The content of the conductive metal contained in the base particles in 100% by volume of the conductive particles (vol%) twenty one 17 33 35 36 34 The content of conductive metal contained in the conductive part in 100% by volume of conductive particles (vol%) 14 18 0 0 0 0 The first ratio (%) 85 60 0 0 0 0 The second ratio (%) 15 30 0 0 0 0 Cohesion ○ ○ × × × ○ Adhesion of conductive part ○ ○ × × × × Connection structure Connection resistance ○ ○ ○ ○ ○ ○ × Insulation reliability ○ ○ ○ ○ ○ × × × ○

1: Conductive particles 2: Substrate particles 3: conductive part 11: Conductive particles 11a: protrusion 12: Conductive part 12a: protrusion 13: core material 14: Insulating substance 21: Conductive particles 21a: protrusion 22: Conductive part 22a: protrusion 22A: The first conductive part 22Aa: protrusion 22B: The second conductive part 22Ba: protrusion 51: Connection structure 52: The first connection object member 52a: first electrode 53: The second connection object member 53a: 2nd electrode 54: connecting part R1: area R2: area

Fig. 1 is a cross-sectional view showing conductive particles according to the first embodiment of the present invention. Fig. 2 is a cross-sectional view showing conductive particles according to a second embodiment of the present invention. Fig. 3 is a cross-sectional view showing conductive particles according to a third embodiment of the present invention. FIG. 4 is a schematic diagram for explaining each area in the substrate particle where the presence or absence of conductive metal is confirmed. Fig. 5 is a front cross-sectional view schematically showing a connection structure using conductive particles according to the first embodiment of the present invention.

Claims (15)

A conductive particle comprising a substrate particle and a conductive part arranged on the surface of the substrate particle, The substrate particle contains a conductive metal in the interior of the substrate particle. The conductive particle according to claim 1, wherein the porosity of the substrate particle is 10% or more. The conductive particle of claim 1 or 2, wherein the conductive metal includes nickel, gold, palladium, silver, or copper. The conductive particle according to claim 1 or 2, wherein the conductive part contains nickel, gold, palladium, silver, or copper. The conductive particle of claim 1 or 2, wherein the 10% K value of the conductive particle is 100 N/mm ² or more and 25000 N/mm ² or less. The conductive particle of claim 1 or 2, wherein the 30% K value of the conductive particle is 100 N/mm ² or more and 15000 N/mm ² or less. The conductive particle of claim 1 or 2, wherein the ratio of the 10% K value of the conductive particle to the 30% K value of the conductive particle is 1.5 or more and 5 or less. The conductive particle of claim 1 or 2, wherein the particle diameter of the conductive particle is 0.1 μm or more and 1000 μm or less. The conductive particle according to claim 1 or 2, wherein in 100% by volume of the conductive particle, the content of the conductive metal contained in the substrate particle is 0.1% by volume to 30% by volume. The conductive particle according to claim 1 or 2, which has protrusions on the outer surface of the conductive portion. The conductive particle of claim 1 or 2, which includes an insulating substance arranged on the outer surface of the conductive part. A conductive material comprising the conductive particles according to any one of claims 1 to 11, and a binder resin. Such as the conductive material of claim 12, which contains a plurality of the above-mentioned conductive particles, When the region from the outer surface of the substrate particle toward the center that is a distance of 1/2 of the particle diameter of the substrate particle is defined as region R1, in 100% of the total number of the conductive particles, of the substrate particle The ratio of the number of conductive particles in which the conductive metal is present in the region R1 is 50% or more. Such as the conductive material of claim 12 or 13, which contains a plurality of the above-mentioned conductive particles, When the region from the center of the substrate particle toward the outer surface that is a distance of 1/2 of the particle diameter of the substrate particle is defined as the region R2, in 100% of the total number of the conductive particles, of the substrate particle The ratio of the number of conductive particles in which the conductive metal is present in the region R2 is 5% or more. A connection structure comprising: a first connection object member having a first electrode on the surface; A second connection object member having a second electrode on the surface; and A connecting portion that connects the first connection object member and the second connection object member; The material of the connection part is the conductive particles according to any one of claims 1 to 11, or a conductive material containing the conductive particles and a binder resin, The first electrode and the second electrode are electrically connected by the conductive particles.

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