TWI703584B - Conductive particles, conductive materials, and connection structures - Google Patents

Abstract

The present invention provides a conductive particle capable of inhibiting corrosion of a conductive layer containing nickel in the presence of either acid or alkali. The conductive particle of the present invention includes a substrate particle and a conductive layer containing nickel arranged on the surface of the substrate particle, and the conductive layer containing nickel is an alloy layer containing at least one of nickel and tin and indium. The total average content of tin and indium in 100% by weight of the area from the outer surface toward the inner side to the thickness 1/2 of the conductive layer containing nickel is less than 5% by weight.

Description

Conductive particles, conductive materials, and connection structures

The present invention relates to a conductive particle in which a conductive layer containing nickel 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 these anisotropic conductive materials, conductive particles are dispersed in the binder resin. The above-mentioned anisotropic conductive materials are, for example, used for the connection of flexible printed substrates and glass substrates (FOG (Film on Glass)), the connection of semiconductor chips and flexible printed substrates (COF (Chip on Film)), and the connection of semiconductor chips and glass substrates. (COG (Chip on Glass)), and the connection of flexible printed circuit board and epoxy glass substrate (FOB (Film on Board)), etc., to obtain various connection structures. For example, when the electrode of a semiconductor wafer and the electrode of a glass substrate are electrically connected using the above-mentioned anisotropic conductive material, an anisotropic conductive material containing conductive particles is arranged on the glass substrate. Next, the semiconductor wafers are stacked, and heated and pressurized. Thereby, the anisotropic conductive material is cured, and the electrodes are electrically connected via the conductive particles to obtain a connected structure. As an example of the above-mentioned conductive particle, in the following patent document 1, the conductive particle which has a substrate particle and the conductive metal layer which coat|covers the surface of this substrate particle is disclosed. Specific examples of the metal constituting the conductive metal layer include nickel, nickel alloys (Ni-Au, Ni-Pd, Ni-Pd-Au, Ni-Ag, Ni-P, Ni-B, Ni-Zn , Ni-Sn, Ni-W, Ni-Co, Ni-Ti); copper, copper alloy (Cu and selected from Fe, Co, Ni, Zn, Sn, In, Ga, Tl, Zr, W, Mo, Rh , Ru, Ir, Ag, Au, Bi, Al, Mn, Mg, P, B is composed of at least one metal element alloy, preferably with Ag, Ni, Sn, Zn alloy); , Silver alloy (Ag and selected from Fe, Co, Ni, Zn, Sn, In, Ga, Tl, Zr, W, Mo, Rh, Ru, Ir, Au, Bi, Al, Mn, Mg, P, B The alloy of at least one metal element in the composition group, preferably Ag-Ni, Ag-Sn, Ag-Zn); tin, tin alloy (such as Sn-Ag, Sn-Cu, Sn-Cu-Ag, Sn -Zn, Sn-Sb, Sn-Bi-Ag, Sn-Bi-In, Sn-Au, Sn-Pb, etc.). Patent Document 2 below discloses conductive particles in which a metal coating layer is formed on the surface of resin particles. The metal coating layer is formed by an electroless nickel plating step using a boron compound and a hypophosphorous acid compound as a reducing agent. In Patent Document 2, it is described that the above-mentioned metal coating layer may contain other metals that eutectoid with nickel in addition to nickel, boron, and phosphorus. Examples of other metals that are eutected with nickel include cobalt, copper, zinc, iron, manganese, chromium, vanadium, molybdenum, palladium, tin, indium, tungsten, and rhenium. In the following Patent Document 3, conductive particles provided with substrate particles and a conductive layer containing nickel arranged on the surface of the substrate particles are disclosed. The conductive layer includes an alloy layer of nickel and tin. The average content of tin in the entire 100% by weight of the conductive layer is 5% by weight or more and 50% by weight or less. [Prior Art Document] [Technical Document] [Patent Document 1] Japanese Patent Laid-open No. 2013-125649 [Patent Document 2] Japanese Patent Laid-Open No. 2008-41671 [Patent Document 3] Japanese Patent Laid-Open No. 2015-130328 Bulletin

[Problem to be Solved by the Invention] If the previous conductive particles as described in Patent Documents 1 and 2 are exposed to the presence of acid, corrosion of the conductive layer containing nickel may occur. In addition, if the previous conductive particles described in Patent Documents 1 to 3 are exposed to the presence of alkali, corrosion of the conductive layer containing nickel may occur. In addition, in the case of obtaining a connected structure by connecting the electrodes using the conventional conductive particles, when the connecting structure is exposed to the presence of acid or alkali, the connection resistance between the electrodes may increase. Furthermore, if the average content of tin in the conductive layer containing nickel increases, the specific resistance of the conductive layer tends to increase, and the conductive layer tends to become brittle. Therefore, it is likely to be caused by compression when connecting the electrodes Cracks in the conductive layer occur. The object of the present invention is to provide a conductive particle capable of suppressing corrosion of a conductive layer containing nickel in the presence of either acid or alkali. Moreover, the object of the present invention is also to provide a conductive material and a connection structure using the above-mentioned conductive particles. [Technical Means for Solving the Problem] According to a broad aspect of the present invention, there is provided a conductive particle comprising a substrate particle and a conductive layer containing nickel disposed on the surface of the substrate particle, and the above-mentioned nickel-containing conductive layer The conductive layer includes nickel, and an alloy layer of at least one of tin and indium. The total of tin and indium in 100% by weight of the area from the outer surface toward the inner side to the thickness 1/2 of the above-mentioned conductive layer including nickel The average content is less than 5% by weight. In a specific aspect of the conductive particles of the present invention, the total average content of tin and indium in the region from the outer surface toward the inner side to the thickness of 1/4 of the conductive layer containing nickel is higher than that of the above-mentioned nickel-containing conductive layer. The conductive layer has a large average content of tin and indium in the region from the position of the thickness 1/4 to the position of the thickness 1/2 of the thickness from the outer surface toward the inner side. In a specific aspect of the conductive particles of the present invention, the total content of tin and indium is the largest in 100% by weight of the region from the outer surface to the inner side of the thickness 1/4 of the conductive layer containing nickel The value is 50% by weight or less. In a specific aspect of the conductive particles of the present invention, the conductive layer containing nickel has protrusions on the outer surface. In a specific aspect of the conductive particles of the present invention, the volume resistivity is 0.003 Ω·cm or less. In a specific aspect of the conductive particles of the present invention, the total average content of tin and indium in 100% by weight of the region from the inner surface to the outside to the thickness 1/2 of the conductive layer containing nickel is not Up to 5% by weight. In a specific aspect of the conductive particle of the present invention, the conductive particle further includes an insulating substance arranged on the outer surface of the conductive layer containing nickel. 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. According to a broad aspect of the present invention, there is provided a connection structure including: a first connection object member; a second connection object member; and a connecting portion that connects the first connection object member and the second connection object member ; And the material of the connecting portion is the conductive particles, or a conductive material containing the conductive particles and a binder resin. [Effects of the invention] In the conductive particles of the present invention, a substrate particle and a conductive layer containing nickel are arranged on the surface of the substrate particle, and the conductive layer containing nickel includes nickel, tin, and In an alloy layer of at least one type of indium, the total average content of tin and indium is less than 5% by weight in 100% by weight of the area from the outer surface of the conductive layer containing nickel to the inner side to the thickness 1/2. Therefore, the corrosion of the conductive layer containing nickel can be suppressed in the presence of either acid or alkali.

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[表3]

Hereinafter, the details of the present invention will be described. (Electroconductive particle) The electroconductive particle of this invention is equipped with the electrically conductive layer which arrange|positions on the surface of this substrate particle and nickel which is a substrate particle. In addition, in the conductive particles of the present invention, the conductive layer containing nickel includes nickel and an alloy layer of at least one of tin and indium. In the conductive particles of the present invention, the total average content of tin and indium is less than 5% by weight in 100% by weight of the region from the outer surface toward the inner side to the thickness 1/2 of the conductive layer containing nickel. The conductive particles may be exposed to acid or alkali conditions due to acidic gas or alkaline gas in the atmosphere, or acidic or alkaline components other than the conductive particles contained in the conductive material. By adopting the above-mentioned structure in the conductive particles of the present invention, corrosion of the conductive layer containing nickel can be suppressed in the presence of either acid or alkali. Even if the above-mentioned conductive particles are exposed to the presence of acid or alkali, corrosion of the conductive layer containing nickel is not likely to occur, so the performance as conductive particles can be maintained high. In the present invention, even in the presence of acid, corrosion of the conductive layer containing nickel can be suppressed, and further, the corrosion of the conductive layer containing nickel in the presence of alkali can be suppressed. In addition, since the corrosion of the conductive layer containing nickel can be suppressed, when the conductive particles of the present invention are used to electrically connect the electrodes to obtain a connected structure, even if the conductive particles before connecting the electrodes are exposed to acid Or in the presence of alkali, the connection resistance can be kept low. In addition, since corrosion of the conductive layer containing nickel can be suppressed, even if the connection structure is exposed to the presence of acid or alkali, the connection resistance can be maintained low. Furthermore, by adopting the above-mentioned structure in the conductive particles of the present invention, the connection reliability between electrodes under high humidity can also be improved. Furthermore, by adopting the above-mentioned constitution in the conductive particles of the present invention, it is possible to suppress aggregation of the conductive particles. By suppressing aggregation of conductive particles, the connection resistance between electrodes can also be effectively reduced. Furthermore, in the conductive particles of the present invention, since the conductive layer containing nickel contains at least one of tin and indium, the strong magnetic properties of nickel can be suppressed, and the effect of suppressing aggregation due to magnetism can be obtained. Therefore, a plurality of conductive particles can be efficiently arranged on the electrode. Therefore, when the electrodes are electrically connected, the connection reliability and conduction reliability between the electrodes can be further improved. Furthermore, it is possible to prevent electrical connection between electrodes adjacent to each other in the lateral direction that cannot be connected, and to further improve insulation reliability. In addition, the conductive particles of the present invention are conductive because the total average content of tin and indium in 100% by weight of the region from the outer surface toward the inner side to the thickness 1/2 of the conductive layer containing nickel is less than 5% by weight. The layer is not easy to become brittle, and it is not easy to cause corrosion of the conductive layer in the presence of acid or alkali, so it can also inhibit the aggregation of conductive particles accompanying the corrosion reaction of the conductive layer. From the viewpoint of further improving the reliability of the connection between the electrodes, the total average content of tin and indium in 100% by weight of the entire conductive layer containing nickel is preferably 1% by weight or more, more preferably 2% by weight or more , And preferably less than 5% by weight, more preferably less than 5% by weight. In addition, when the total average content of tin and indium is less than 5% by weight in the total 100% by weight of the conductive layer containing nickel, the conductive layer tends to be less brittle. Therefore, when the total average content of tin and indium in the total 100% by weight of the conductive layer containing nickel is less than 5% by weight, the corrosion of the conductive layer in the presence of acid or alkali is less likely to occur, and the conductive layer can be more Effectively maintain low connection resistance after exposure to acid or alkali. In addition, when the total average content of tin and indium is less than 5% by weight in the total 100% by weight of the conductive layer containing nickel, the specific resistance of the conductive layer tends not to rise easily, and it is not easy to cause The rupture of the conductive layer caused by the compression during the indirect connection can effectively keep the connection resistance low. From the viewpoint of further improving the adhesion between the substrate particles and the conductive layer containing nickel, and further improving the connection reliability between the electrodes, the conductive layer containing nickel is from the inner surface toward the outside to the thickness of 1/2 In 100% by weight of the region (R1), the total average content of tin and indium is preferably 5% by weight or less, more preferably less than 5% by weight, still more preferably 3% by weight or less, and particularly preferably 2% by weight the following. The above-mentioned area (R1) is the area on the inner side of the conductive layer 3 containing nickel than the dotted line L1 in FIG. 4(a). In 100% by weight of the area (R2) from the outer surface to the inner side of the thickness 1/2 of the conductive layer containing nickel, the total average content of tin and indium is less than 5% by weight. From the viewpoint of further improving the reliability of the connection between the electrodes, in the total 100% by weight of the conductive layer containing nickel, the conductive layer containing nickel extends from the outer surface toward the inner side to the region (R2) of thickness 1/2 In 100% by weight, the total average content of tin and indium is preferably 3% by weight or less, more preferably 2% by weight or less. The above-mentioned area (R2) is the area outside the dotted line L1 of the conductive layer 3 containing nickel in FIG. 4(a). The total average content of tin and indium in the above-mentioned region (R1) may be less than the total average content of tin and indium in the above-mentioned region (R2), or it may be equal to the total of tin and indium in the above-mentioned region (R2) The average content is the same, and may be more than the total average content of tin and indium in the above-mentioned region (R2). From the viewpoint of further improving the adhesion between the substrate particles and the conductive layer containing nickel, further improving the connection reliability between the electrodes, and further suppressing the corrosion of the conductive particles due to acid or alkali, it is preferably The total average content of tin and indium in the above region (R1) is less than the total average content of tin and indium in the above region (R2). From the viewpoint of further improving the adhesion between the substrate particles and the conductive layer containing nickel, and further improving the connection reliability between the electrodes, the conductive layer containing nickel is from the outer surface toward the inner side to a thickness of 1/4 In 100% by weight of the region (R3), the total average content of tin and indium is preferably 20% by weight or less, more preferably 10% by weight or less. The above-mentioned area (R3) is an area outside the dotted line L2 of the conductive layer 3 containing nickel in FIG. 4(b). From the viewpoint of further improving the adhesion between the substrate particles and the conductive layer containing nickel, and further improving the connection reliability between the electrodes, the conductive layer containing nickel is 1/4 of the thickness from the outer surface toward the inner side The total average content of tin and indium in 100% by weight of the region (R4) between the position and the thickness 1/2 position is preferably 10% by weight or less, more preferably 1% by weight or less. The above-mentioned area (R4) is the area between the dotted line L1 and the dotted line L2 of the conductive layer 3 containing nickel in FIG. 4(b). From the viewpoint of further improving the adhesion between the substrate particles and the conductive layer containing nickel, further improving the connection reliability between the electrodes, and further suppressing the corrosion of the conductive particles due to acid or alkali, it is preferably The total average content of tin and indium in the aforementioned region (R3) is greater than the total average content of tin and indium in the aforementioned region (R4). In the region (R3), when the region (R3) is viewed as a whole, tin and indium may be unevenly distributed. The above-mentioned region (R3) may have a portion where the total content of tin and indium is relatively large and a portion where the total content of tin and indium is relatively small. In the aforementioned region (R3), unevenness may be observed in the total content of tin and indium. In terms of further improving the adhesion between the substrate particles and the conductive layer containing nickel, further improving the connection reliability between the electrodes, and further suppressing the corrosion of the conductive particles due to acid or alkali, the above-mentioned area ( In R3) 100% by weight, the maximum of the total content of tin and indium is preferably 5% by weight or more, more preferably 10% by weight or more, and preferably 50% by weight or less, and more preferably 45% by weight or less . The maximum value of the total content of tin and indium indicates the content in the position where the total content of tin and indium in the region (R3) is the largest. The maximum value of the total content of tin and indium in 100% by weight of the above region (R3) can be measured as follows. Using a focused ion beam, a thin film slice of the obtained conductive particles is made. Using an electric field radiation type transmission electron microscope ("JEM-2010FEF" manufactured by JEOL Ltd.), using an energy dispersive X-ray analyzer (EDS) to analyze the thickness of nickel, tin and indium of the conductive layer containing nickel The content is measured to obtain the distribution result of the content of nickel, tin, and indium in the thickness direction of the conductive layer containing nickel. According to this result, the maximum value of the total content of tin and indium in 100% by weight of the region (R3) can be obtained. In the conductive particles of the present invention, it is preferable that the melting point of the conductive layer containing nickel is 300°C or higher. The conductive layer with a melting point of 300°C or higher and containing nickel generally has a lower average content of tin, so it is different from the solder layer that is usually called solder, and is different from the solder layer with a lower melting point. The upper limit of the melting point of the conductive layer containing nickel is not particularly limited. The melting point of the conductive layer containing nickel may be 3000°C or lower, 2000°C or lower, or 1000°C or lower. The melting point of the conductive layer containing nickel may be 400°C or higher, or 500°C or higher. From the viewpoint of further reducing the connection resistance and further improving the connection reliability between the electrodes, the compressive elastic modulus (10% K value) when the conductive particles are compressed by 10% is preferably 10 N/mm ² Above, it is more preferably 50 N/mm ² or more, and more preferably 4000 N/mm ² or less, and more preferably 3000 N/mm ² or less. The compression modulus (10% K value) in the conductive particles can be measured as follows. Using a micro-compression tester, the conductive particles are compressed with a cylindrical (50 μm diameter, diamond-made) smooth indenter end surface at 25°C and a maximum test load of 90 mN for 30 seconds. Measure the load value (N) and compression displacement (mm) at this time. The compressive elastic modulus can be obtained from the obtained measured value by the following formula. As the aforementioned micro-compression tester, for example, "Fischerscope H-100" manufactured by Fischer, etc. is used. K value (N/mm ² )=(3/2 ^1/2 )・F・S ^-3/2・R ^-1/2 F: Load value when conductive particles compress and deform 10% (N) S: Conductive Compression displacement (mm) when the conductive particle is compressed and deformed by 10% R: the radius of the conductive particle (mm) The above-mentioned compression elastic modulus generally and quantitatively indicates the hardness of the conductive particle. By using the above-mentioned compression elastic modulus, it is possible to quantitatively and uniquely express the hardness of the conductive particles. From the viewpoint of further suppressing aggregation of conductive particles and reducing the connection resistance between electrodes more effectively, the volume resistivity of the conductive particles is preferably 0.003 Ω·cm or less. Hereinafter, the present invention will be described in detail while referring 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 the base particle 2 and the conductive layer 3 containing nickel. The conductive layer 3 is disposed on the surface of the substrate particle 2. In the first embodiment, the conductive layer 3 is in contact with the surface of the substrate particle 2. The conductive particle 1 is a coating particle in which the surface of the substrate particle 2 is coated with the conductive layer 3. In the conductive particle 1, the conductive layer 3 containing nickel is a single-layer conductive layer. In the conductive particles 1, the conductive layer 3 containing nickel is an alloy layer containing at least one of nickel and tin and indium. The total average content of tin and indium in the 100% by weight of the area from the outer surface toward the inner side to the thickness 1/2 of the conductive layer 3 containing nickel is less than 5% by weight. 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 layer 3 has no 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 layer 3. In this case, a conductive layer containing no nickel may be arranged between the conductive layer 3 and the insulating material. In the conductive particle 1, the base particle 2 is in contact with the conductive layer 3 containing nickel. A conductive layer containing no nickel can be arranged between the substrate particles and the conductive layer containing nickel, or a conductive layer containing no nickel can be arranged on the outer surface of the conductive layer containing nickel. Fig. 2 shows a cross-sectional view of conductive particles according to a second embodiment of the present invention. The conductive particle 11 shown in FIG. 2 has a base particle 2, a conductive layer 12 containing nickel, a plurality of core materials 13, and a plurality of insulating materials 14. The conductive layer 12 containing nickel is arranged on the surface of the substrate particle 2 in a manner in contact with the substrate particle 2. In the conductive particles 11, the conductive layer 12 containing nickel is a single-layer conductive layer. In the conductive particles 11, the conductive layer 12 containing nickel is an alloy layer containing at least one of nickel and tin and indium. The total average content of tin and indium in 100% by weight of the area from the outer surface toward the inner side to the thickness 1/2 of the conductive layer 12 containing nickel is less than 5% by weight. The conductive particle 11 has a plurality of protrusions 11a on the conductive surface. The conductive layer 12 containing nickel 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 layer 12 containing nickel. The core material 13 is arranged inside the protrusions 11a and 12a. The conductive layer 12 containing nickel coats a plurality of core materials 13. The outer surface of the conductive layer 12 containing nickel is raised by a plurality of core materials 13, thereby forming protrusions 11a and 12a. The conductive particles 11 have an insulating substance 14 arranged on the outer surface of the conductive layer 12 containing nickel. At least a part of the area of the outer surface of the conductive layer 12 containing nickel is covered by the 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 layer. However, the conductive particles of the present invention may not necessarily have an insulating substance. 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 base particle 2, a conductive layer 22 containing nickel, a plurality of core materials 13, and a plurality of insulating materials 14. As a whole, the conductive layer 22 containing nickel has a first conductive layer 22A on the side of the substrate particle 2 and a second conductive layer 22B on the side opposite to the side of the substrate particle 2. In the conductive particles 11 and the conductive particles 21, only the conductive layer is different. That is, in the conductive particle 11, the conductive layer 12 of a one-layer structure is formed, and in contrast to this, in the conductive particle 21, the 1st conductive layer 22A and the 2nd conductive layer 22B of a two-layer structure are formed. The first conductive layer 22A and the second conductive layer 22B are formed as different conductive layers. The first conductive layer 22A is arranged on the surface of the substrate particle 2. The first conductive layer 22A is arranged between the substrate particles 2 and the second conductive layer 22B. The first conductive layer 22A is in contact with the substrate particles 2. The second conductive layer 22B is in contact with the first conductive layer 22A. Therefore, the first conductive layer 22A is arranged on the surface of the substrate particle 2, and the second conductive layer 22B is arranged on the surface of the first conductive layer 22A. The conductive particle 21 has a plurality of protrusions 21a on the conductive surface. The conductive layer 22 has a plurality of protrusions 22a on the outer surface. The first conductive layer 22A has a plurality of protrusions 22Aa on the outer surface. The second conductive layer 22B has a plurality of protrusions 22Ba on the outer surface. In the conductive particles 21, the conductive layer 22 containing nickel is a two-layer conductive layer. In the conductive particles 21, the conductive layer 22 containing nickel is an alloy layer containing at least one of nickel and tin and indium. Therefore, each of the first conductive layer 22A and the second conductive layer 22B is an alloy layer containing at least one of nickel and tin and indium. The total average content of tin and indium in 100% by weight of the area from the outer surface toward the inner side to the thickness 1/2 of the conductive layer 22 containing nickel is less than 5% by weight. Hereinafter, other details of the conductive particles will be described. (Substrate particles) Examples of the above-mentioned substrate particles include resin particles, inorganic particles other than metal particles, organic-inorganic hybrid particles, metal particles, and the like. The substrate particles are preferably substrate particles other than metal particles, and more preferably resin particles, inorganic particles other than metal particles, or organic-inorganic hybrid particles. The aforementioned substrate particles may have a core and a shell arranged on the surface of the core, or may be core-shell particles. The core may be an organic core, and the shell may be an inorganic shell. The aforementioned substrate particles are more preferably resin particles or organic-inorganic hybrid particles, and may be resin particles or organic-inorganic hybrid particles. When connecting the electrodes using the conductive particles, after the conductive particles are arranged between the electrodes, the conductive particles are compressed by pressure bonding. If the substrate particles are resin particles or organic-inorganic mixed particles, the conductive particles are easily deformed during the pressure bonding, and the contact area between the conductive particles and the electrode becomes larger. Therefore, the reliability of conduction between the electrodes can be further improved. As the resin for forming the above-mentioned resin particles, various organic substances can be suitably used. Examples of resins used to form the resin particles include polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene, and polybutadiene; polymethacrylic acid Acrylic resins such as methyl and polymethyl acrylate; polycarbonate, polyamide, phenolic 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, polyether, polyphenylene ether, polyacetal, polyimide, polyamide Amine, polyether ether ketone, polyether agglomerate, divinylbenzene polymer, and divinylbenzene copolymer, etc. As said divinylbenzene copolymer etc., a divinylbenzene-styrene copolymer, a divinylbenzene-(meth)acrylate copolymer, etc. are mentioned. Since it is easy to control the hardness of the resin particles in an appropriate range, the resin used to form the resin particles is preferably polymerized by polymerizing one or more polymerizable monomers with ethylenically unsaturated groups Things. When polymerizing a polymerizable monomer having an ethylenically unsaturated group to obtain the resin particles, examples of the polymerizable monomer having an ethylenically unsaturated group include non-crosslinkable monomers and crosslinkable monomers. body. Examples of the above-mentioned non-crosslinkable monomers include: styrene-based monomers such as styrene and α-methylstyrene; carboxyl group-containing monomers such as (meth)acrylic acid, maleic acid, and maleic anhydride. Monomers; methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (methyl) ) Lauryl acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, iso-(meth)acrylate, etc. (meth) ) Alkyl acrylate compounds; 2-hydroxyethyl (meth)acrylate, glycerol (meth)acrylate, polyoxyethylene (meth)acrylate, glycidyl (meth)acrylate and other oxygen atoms ( Meth)acrylate compounds; (meth)acrylonitrile and other nitrile-containing monomers; vinyl ether compounds such as methyl vinyl ether, ethyl vinyl ether, and propyl vinyl ether; vinyl acetate, vinyl butyrate , Vinyl laurate, vinyl stearate and other acid vinyl ester compounds; ethylene, propylene, isoprene, butadiene and other unsaturated hydrocarbons; (meth)acrylic acid trifluoromethyl, (meth)acrylic acid five Halogen-containing monomers such as ethyl fluoride, vinyl chloride, vinyl fluoride, chlorostyrene, etc. Examples of the above-mentioned crosslinkable monomers include tetramethylolmethane tetra(meth)acrylate, tetramethylolmethane tri(meth)acrylate, and tetramethylolmethane di(meth)acrylate. , Trimethylolpropane tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate, glycerol tri(meth)acrylate, glycerol tri(meth)acrylate Meth) acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, (poly)butylene glycol di(meth)acrylate, 1,4 -Multifunctional (meth)acrylate compounds such as butanediol di(meth)acrylate; triallyl (iso)cyanurate, triallyl trimellitate, divinylbenzene, diphthalate Allyl ester, diallyl acrylamide, diallyl ether, γ-(meth) acryloxypropyl trimethoxysilane, trimethoxysilyl styrene, vinyl trimethoxysilane, etc. The monomer of silane, etc. The above-mentioned resin particles can be obtained by polymerizing the above-mentioned polymerizable monomer having an ethylenically unsaturated group by a known method. Examples of the method include: suspension polymerization in the presence of a radical polymerization initiator, and the use of non-crosslinked seed particles to swell the monomer and the radical polymerization initiator together. Methods of aggregation, etc. When the above-mentioned substrate particles are inorganic particles or organic-inorganic mixed particles other than metals, examples of the inorganic substances used to form the substrate particles include: silica, alumina, barium titanate, zirconia, carbon black, etc. . The above-mentioned inorganic substance is preferably not a metal. The above-mentioned particles formed of silicon oxide are not particularly limited. Examples include particles obtained by hydrolyzing a silicon compound having two or more hydrolyzable alkoxysilyl groups to form crosslinks. After polymer particles are fired as necessary. Examples of the organic-inorganic hybrid particles include organic-inorganic hybrid particles formed of a crosslinked alkoxysilyl polymer and an acrylic resin. The aforementioned organic-inorganic hybrid particles are preferably core-shell organic-inorganic hybrid particles having a core and a shell arranged on the surface of the core. The aforementioned core is preferably an organic core. The aforementioned shell is preferably an inorganic shell. From the viewpoint of effectively reducing the connection resistance between the electrodes, the substrate particle is preferably an organic-inorganic hybrid particle having an organic core and an inorganic shell arranged on the surface of the organic core. Examples of the material used to form the organic core include the resin used to form the resin particles described above. Examples of the material for forming the above-mentioned inorganic shell include the above-mentioned inorganic substances for forming the substrate particles. The material used to form the above-mentioned inorganic shell is preferably silicon oxide. The 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 sintering the shell. The aforementioned metal alkoxide is preferably silane alkoxide. The above-mentioned inorganic shell is preferably formed of a silanate. The particle diameter of the above-mentioned core is preferably 0.5 μm or more, more preferably 1 μm or more, and preferably 500 μm or less, more preferably 100 μm or less, still more preferably 50 μm or less, particularly preferably 20 μm or less, most preferably It is preferably 10 μm or less. If the particle diameter of the above-mentioned core is more than the above-mentioned lower limit and below the above-mentioned upper limit, conductive particles more suitable for electrical connection between electrodes can be obtained, and the substrate particles can be preferably used for the purpose of conductive particles. For example, if the particle size of the core is more than the lower limit and less than the upper limit, when the conductive particles are used to connect the electrodes, the contact area between the conductive particles and the electrode is sufficiently increased, and the conductive portion can be formed It is not easy to form agglomerated conductive particles. In addition, the gap between the electrodes connected via conductive particles does not become too large, and it is possible to make it difficult to peel off the conductive portion from the surface of the substrate particle. The particle size of the nucleus refers to the diameter when the nucleus is a true spherical shape, and refers to the maximum diameter when the nucleus is a shape other than the true spherical shape. In addition, the particle diameter of the core refers to the average particle diameter obtained by measuring the core with any particle diameter measuring device. For example, a particle size distribution measuring machine using the principles of laser light scattering, resistance change, image analysis after shooting, etc. can be used. The thickness of the above-mentioned shell is preferably 100 nm or more, more preferably 200 nm or more, and preferably 5 μm or less, and more preferably 3 μm or less. If the thickness of the shell is at least the above lower limit and below the above upper limit, conductive particles more suitable for electrical connection between electrodes can be obtained, and the substrate particles can be preferably used for the purpose of conductive particles. The thickness of the aforementioned shell is the average thickness per one substrate particle. Through the control of the sol-gel method, the thickness of the shell can be controlled. In the case where the aforementioned substrate particles are metal particles, the metal used as the material of the metal particles includes silver, copper, nickel, silicon, gold, and titanium. However, it is preferable that the aforementioned substrate particles are not metal particles, and it is preferable that they are not copper particles. The particle size of the substrate particles is preferably 0.1 μm or more, more preferably 1 μm or more, still more preferably 1.5 μm or more, particularly preferably 2 μm or more, and preferably 1000 μm or less, more preferably 500 μm or less , Further more preferably 300 μm or less, still more preferably 50 μm or less, still more preferably 30 μm or less, particularly preferably 5 μm or less, and most preferably 3 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 gap between the electrodes connected via the conductive particles can be further reduced. Connect resistance. Furthermore, when a conductive layer is formed on the surface of the substrate particle by electroless plating, it is possible to hardly 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 interval between the electrodes can be made smaller. The particle diameter of the aforementioned substrate particle indicates the diameter when the substrate particle is a true spherical shape, and indicates the maximum diameter when the substrate particle is not a true spherical shape. The particle diameter of the substrate particles is particularly preferably 2 μm or more and 5 μm or less. If the particle size of the substrate particles is in the range of 2 to 5 μm, the gap between the electrodes can be made smaller, and even if the thickness of the conductive layer is thickened, smaller conductive particles can be obtained. (Conductive layer) The conductive particle of the present invention includes a substrate particle and a conductive layer containing nickel arranged on the surface of the substrate particle. The conductive layer containing nickel contains at least one of nickel, and tin and indium. The total average content of tin and indium in the 100% by weight of the region from the outer surface toward the inner side to the thickness 1/2 of the conductive layer containing nickel is less than 5% by weight. Regarding the conductive layer containing nickel, the conductive layer containing nickel may be described as the conductive layer X in the column of (conductive layer) below. In the above-mentioned conductive layer X, the conductive layer not containing nickel is not included, and the conductive layer portion not containing nickel is not included. From the viewpoint of effectively improving the conductivity, in 100% by weight of the entire conductive layer X, the higher the average content of nickel, the better. Therefore, in the entire 100% by weight of the conductive layer X, the average content of nickel is preferably 50% by weight or more, more preferably 65% by weight or more, still more preferably 70% by weight or more, and still more preferably 80% by weight or more , And more preferably 85% by weight or more, particularly preferably 90% by weight or more, and most preferably 95% by weight or more. In 100% by weight of the entire conductive layer X, the average content of nickel is preferably 99% by weight or less, more preferably 98% by weight or less, and still more preferably 97% by weight or less. If the average content of nickel is more than the above lower limit, the connection resistance between the electrodes can be further reduced. In addition, when there is less oxide film on the surface of the electrode or the conductive layer, the higher the average content of nickel, the lower the connection resistance between the electrodes. The method for measuring the contents of nickel, tin, and indium in the conductive layer containing nickel (conductive layer X) can use various known analysis methods, and is not particularly limited. It can be measured using a high-frequency inductively coupled plasma emission spectrometer ("ICP-AES" manufactured by Horiba), or a fluorescent X-ray analyzer ("EDX-800HS" manufactured by Shimadzu). The contents of nickel, tin, and indium in each region in the thickness direction of the conductive layer X can be measured using an electric field radiation type transmission electron microscope ("JEM-2010FEF" manufactured by JEOL Ltd.). The thickness of the entire conductive layer X is preferably 0.005 μm or more, more preferably 0.01 μm or more, still more preferably 0.05 μm or more, and preferably 1 μm or less, and more preferably 0.3 μm or less. If the thickness of the entire conductive layer X is greater than or equal to the aforementioned lower limit and less than or equal to the aforementioned 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. The thickness of the entire conductive layer X is particularly preferably 0.05 μm or more and 0.3 μm or less. More preferably, the particle size of the substrate particles is 2 μm or more and 5 μm or less, and the thickness of the entire conductive layer X is 0.05 μm or more and 0.3 μm or less. In this case, the conductive particles can be better used for the purpose of flowing a larger current. Furthermore, when the conductive particles are compressed and the electrodes are connected, damage to the electrodes can be further suppressed. The thickness of the conductive layer X can be measured by observation of the cross-section of the conductive particles, for example, using a transmission electron microscope ("JEM-2100" manufactured by JEOL Ltd.). The conductive layer X may also include metals other than nickel, tin, and indium. Examples of metals other than nickel, tin, and indium in the conductive layer X include gold, silver, copper, platinum, zinc, iron, lead, aluminum, cobalt, palladium, chromium, titanium, antimony, and bismuth. , Thallium, germanium, cadmium, silicon, tungsten and molybdenum. These metals may use only 1 type, and may use 2 or more types together. In the case where multiple metals are included in the conductive layer X, multiple metals may also be alloyed. The method of forming the conductive layer X on the surface of the substrate particle is not particularly limited. As a method of forming a conductive layer, for example, a method using electroless plating, a method using electroplating, a method using physical vapor deposition, and coating metal powder or solder paste containing metal powder and a binder on the substrate particles or Other surface methods of conductive layer, etc. Since the formation of the conductive layer is relatively simple, it is preferable to use an electroless plating method. Examples of the method using physical vapor deposition include methods such as vacuum vapor deposition, ion plating, and ion sputtering. The particle size of the conductive particles is preferably 0.5 μm or more, more preferably 1 μm or more, and preferably 100 μm or less, more preferably 20 μm or less, still more preferably 5 μm or less, and particularly preferably 3 μm or less . If the particle size of the conductive particles is more than the above lower limit and below the upper limit, when the above conductive particles are used to connect the electrodes, the contact area between the conductive particles and the electrode can be sufficiently increased, and when the conductive layer is formed, Can not easily form agglomerated conductive particles. In addition, the gap between the electrodes connected via the conductive particles does not become too large, and it is possible to prevent the conductive layer from peeling off the surface of the substrate particles. The particle diameter of the above-mentioned conductive particle represents the diameter when the conductive particle is a true spherical shape, and represents the maximum diameter when the conductive particle is not a true spherical shape. The conductive layer X may be formed of one layer, or may be formed of a plurality of layers. That is, the said conductive layer X may have a laminated structure of 2 or more layers. In addition to the conductive layer X, the conductive particles may include a gold layer, a nickel layer, a palladium layer, a copper layer, a silver layer, or an alloy layer containing tin and silver as the outermost layer. As a method of controlling the contents and average contents of nickel, tin, and indium in each region of the conductive layer X, for example, a method of controlling the pH of the nickel plating solution when the conductive layer X is formed by electroless nickel plating, The method of adjusting the concentration of tin and indium in the nickel plating solution and the method of adjusting the concentration of nickel in the nickel plating solution, etc. In the method of forming by electroless plating, a catalytic step and an electroless plating step are generally performed. Hereinafter, an example of a method of forming a plating layer containing nickel on the surface of a resin particle by electroless plating will be described. In the above-mentioned catalystization step, a catalyst used as a starting point for forming a plating layer by electroless plating is formed on the surface of the resin particles. As a method of forming the above-mentioned catalyst on the surface of the resin particle, for example, the following method can be cited: after adding the resin particle to a solution containing palladium chloride and tin chloride, the surface of the resin particle is treated with an acid solution or an alkali solution. Activation is to precipitate palladium on the surface of the resin particles; and after adding the resin particles to the solution containing palladium sulfate, the surface of the resin particles is activated by the solution containing a reducing agent to precipitate palladium on the surface of the resin particles. In the above electroless plating step, a nickel plating bath containing at least one of a compound containing nickel, the reducing agent, a complexing agent, and a compound containing tin and a compound containing indium is suitably used. By impregnating the resin particles in the nickel plating bath, nickel can be deposited on the surface of the resin particles on which the catalyst is formed, and the above-mentioned conductive layer X can be formed. In addition, when nickel is deposited, at least one of tin and indium is made to eutectoid, thereby forming an alloy plating layer containing nickel and at least one of tin and indium. Examples of the nickel-containing compound include nickel sulfate and nickel chloride. The above-mentioned nickel-containing compound is preferably a nickel salt. As said reducing agent, sodium hypophosphite, dimethylamine borane, sodium borohydride, potassium borohydride, hydrazine monohydrate, hydrazine sulfate, titanium (III) chloride, etc. are mentioned. Examples of the tin-containing compounds include sodium stannate trihydrate, potassium stannate trihydrate, tin sulfate (II), tin chloride (IV) pentahydrate, tin chloride (II) dihydrate, etc. . Examples of the above-mentioned indium-containing compounds include indium acetate (III), indium sulfate (III) trihydrate, indium chloride (III), indium hydroxide (III), and indium nitrate (III). The above-mentioned complexing agents include: monocarboxylic acid complexing agents such as sodium acetate and sodium propionate; dicarboxylic acid complexing agents such as disodium malonate; tricarboxylic acid complexing agents such as disodium succinate; lactic acid, DL-apple Acid, sodium tartrate, sodium citrate, sodium gluconate and other hydroxy acid complexing agents; glycine, EDTA (ethylenediamine tetraacetic acid, ethylenediamine tetraacetic acid) and other amino acid complexing agents; ethylenediamine and other amine complexing agents Mixtures; organic acid complexing agents such as maleic acid; and salts of these. It is preferable to use at least one complexing agent selected from the group consisting of the complexing agents listed here. (Core material) The above-mentioned conductive particles preferably have protrusions on the conductive surface. The aforementioned conductive layer preferably has protrusions on the outer surface. The above-mentioned protrusions are preferably plural. Many oxide films are formed on the surfaces of the electrodes connected by the above-mentioned conductive particles. Furthermore, many oxide films are formed on the surface of the conductive layer of the said electroconductive particle. By using the above-mentioned conductive particles having protrusions, after the conductive particles are arranged between the electrodes, they are pressure-bonded, thereby effectively removing the oxide film by the protrusions. Therefore, the electrode and the conductive particle can be brought into contact with each other more reliably, and the connection resistance between the electrodes can be reduced. Furthermore, when the conductive particles have an insulating substance on the surface, or when the conductive particles are dispersed in a binder resin and used as a conductive material, the protrusions of the conductive particles effectively eliminate the conductivity Insulating material or binder resin between particles and electrodes. Therefore, the reliability of conduction between the electrodes can be improved. In addition, if the conductive particles have protrusions on the outer surface of the conductive layer, the area where the conductive particles contact each other can be reduced. Therefore, aggregation of a plurality of the above-mentioned conductive particles can be suppressed. Therefore, it is possible to prevent electrical connection between unconnectable electrodes, and to further improve insulation reliability. By embedding the core material in the conductive layer, it is easy to make the conductive layer have a plurality of protrusions on the outer surface. However, it is not necessary to use a core material to form protrusions on the outer surface of the conductive particles and the conductive layer. It is preferable not to use a core material. The conductive particles preferably do not have an outer surface for forming the conductive layer. The core material of the uplift. However, the said electroconductive particle may have a core substance which bulges the outer surface of the said electroconductive layer. When the above-mentioned core material is used, it is preferable that the above-mentioned core material is disposed inside or inside the conductive layer. As a method of forming the above-mentioned protrusions, a method of forming a conductive layer by electroless plating after the core material is attached to the surface of the substrate particle; after forming a conductive layer on the surface of the substrate particle by electroless plating, using A method of attaching a core material to form a conductive layer by electroless plating; and a method of adding a core material in the middle of forming a conductive layer on the surface of the substrate particle by electroless plating. As a method of disposing the core material on the surface of the substrate particles, for example, adding the core material to the dispersion of the substrate particles, for example, the core material is gathered and attached to the substrate particles by Van der Waals force. Surface method; and a method of adding a core material to a container with a substrate particle, and attaching the core material to the surface of the substrate particle by using the mechanical action generated by the rotation of the container. In order to easily control the amount of the core material attached, a method of accumulating and attaching the core material to the surface of the substrate particles in the dispersion is preferred. Examples of the material of the aforementioned core material include conductive materials and non-conductive materials. Examples of the above-mentioned conductive substance include conductive non-metals and conductive polymers such as metals, metal oxides, and graphite. As said conductive polymer, polyacetylene etc. are mentioned. Examples of the above-mentioned non-conductive material include silicon oxide, aluminum oxide, barium titanate, and zirconium oxide. In order to effectively remove the oxide film, the core material is preferably harder. Metals are preferred because they can improve conductivity and can effectively reduce connection resistance. The aforementioned core material is preferably metal particles. Regarding the metal as the material of the above-mentioned core substance, the metals listed above as the material of the conductive layer can be suitably used. Specific examples of the material of the aforementioned core material include: barium titanate (Mohs hardness 4.5), nickel (Mohs hardness 5), silicon oxide (silica dioxide, Mohs hardness 6-7), titanium oxide (Mohs hardness 6-7) Hardness 7), zirconia (Mohs hardness 8-9), alumina (Mohs hardness 9), tungsten carbide (Mohs hardness 9), diamond (Mohs hardness 10), etc. The above-mentioned inorganic particles are preferably nickel, silicon oxide, titanium oxide, zirconium oxide, aluminum oxide, tungsten carbide or diamond, more preferably silicon oxide, titanium oxide, zirconium oxide, aluminum oxide, tungsten carbide or diamond, and more preferably oxide Titanium, zirconia, alumina, tungsten carbide or diamond, particularly preferably zirconia, alumina, tungsten carbide or diamond. The Mohs hardness of the material of the core material is preferably 5 or more, more preferably 6 or more, still more preferably 7 or more, and particularly preferably 7.5 or more. 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 alloys, tin-silver alloys, tin-lead-silver alloys and tungsten carbide alloys containing two or more metals. Preferably, it is nickel, copper, silver or gold. The metal used to form the core substance may be the same as or different from the metal used to form the conductive portion. The metal used to form the core material preferably includes a metal used to form the conductive portion. The metal used to form the aforementioned core material preferably contains nickel. The shape of the aforementioned core material is not particularly limited. The shape of the aforementioned core material is preferably a block shape. As the core material, for example, a granular block, agglomerate formed by agglomerating a plurality of fine particles, and an amorphous block are mentioned. The average diameter (average particle diameter) of the above-mentioned core material is preferably 0.001 μm or more, more preferably 0.05 μm or more, and preferably 0.9 μm or less, and more preferably 0.2 μm or less. If the average diameter of the core material is greater than or equal to the lower limit and less than the upper limit, the connection resistance between the electrodes can be effectively reduced. The "average diameter (average particle diameter)" of the above-mentioned core material means the number average diameter (number average particle diameter). The average diameter of the core material is obtained by observing 50 arbitrary core materials with an electron microscope or an optical microscope, and calculating the average value. 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 size of the conductive particles, etc. The average height of the plurality of the protrusions is preferably 0.001 μm or more, more preferably 0.05 μm or more, and preferably 0.9 μm or less, and more preferably 0.2 μm or less. If the average height of the protrusions is more than the lower limit and less than the upper limit, the connection resistance between the electrodes can be effectively reduced. (Insulating material) The conductive particles preferably include an insulating material arranged on the surface of the conductive layer. In this case, if the above-mentioned conductive particles are used for the connection between electrodes, it is possible to further prevent short circuits between adjacent electrodes. Specifically, when a plurality of conductive particles are in contact, since an insulating material exists between the plurality of electrodes, it is possible to prevent short circuits between the electrodes adjacent in the lateral direction instead of 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 layer of the conductive particles and the electrodes can be easily removed. When the conductive particle has a plurality of protrusions on the outer surface of the conductive layer, the insulating material between the conductive layer and the electrode of the conductive particle can be eliminated more easily. In terms of making it easier to remove the insulating material when crimping between electrodes, the insulating material is preferably insulating particles. Specific examples of the insulating resin as the material of the above-mentioned insulating substance include: polyolefin compounds, (meth)acrylate polymers, (meth)acrylate copolymers, block polymers, thermoplastic resins, and thermoplastics Cross-linked resins, thermosetting resins, water-soluble resins, etc. As said polyolefin compound, polyethylene, an ethylene-vinyl acetate copolymer, an ethylene-acrylate copolymer, etc. are mentioned. As said (meth)acrylate polymer, polymethyl (meth)acrylate, polyethyl (meth)acrylate, polybutyl (meth)acrylate, etc. are mentioned. As the above-mentioned block polymer, polystyrene, styrene-acrylate copolymer, SB type styrene-butadiene block copolymer, SBS type styrene-butadiene block copolymer, and the Hydride and so on. As said thermoplastic resin, a vinyl polymer, a vinyl copolymer, etc. are mentioned. As said thermosetting resin, epoxy resin, phenol resin, melamine resin, etc. are mentioned. As said water-soluble resin, polyvinyl alcohol, polyacrylic acid, polyacrylamide, polyvinylpyrrolidone, polyethylene oxide, methyl cellulose, etc. are mentioned. Preferably, it is a water-soluble resin, and more preferably is polyvinyl alcohol. As a method of disposing an insulating substance on the outer surface of the conductive layer, a chemical method, a physical or mechanical method, etc. can be cited. Examples of the above-mentioned chemical methods include interfacial polymerization, suspension polymerization in the presence of particles, and emulsion polymerization. Examples of the above-mentioned physical or mechanical methods include methods using spray drying, mixing, electrostatic adhesion, spraying, dipping, and vacuum deposition. As far as the insulating material is not easily removed, it is preferable to arrange the insulating material on the surface of the conductive layer via a chemical bond. The outer surface of the conductive layer and the surface of the insulating particles may be respectively coated with a compound having a reactive functional group. The outer surface of the conductive layer and the surface of the insulating particle may not be directly chemically bonded, or may be chemically bonded indirectly by a compound having a reactive functional group. After introducing the carboxyl group to the outer surface of the conductive layer, the carboxyl group can also be chemically bonded to the functional group on the surface of the insulating particle via a polymer electrolyte such as polyethyleneimine. The average diameter (average particle diameter) of the insulating material can be appropriately selected according to the particle diameter and use of the conductive particles. The average diameter (average particle diameter) of the insulating material is preferably 0.005 μm or more, more preferably 0.01 μm or more, and preferably 1 μm or less, and more preferably 0.5 μm or less. If the average diameter of the insulating material is greater than or equal to the lower limit, when the conductive particles are dispersed in the binder resin, it is difficult to make the conductive layers of the conductive particles contact each other. If the average diameter of the insulating particles is equal to or less than the above upper limit, the pressure may not be too high when the electrodes are connected, and the insulating particles between the electrodes and the conductive particles may not be heated to a high temperature. The "average diameter (average particle diameter)" of the above-mentioned insulating material means the number average diameter (number average particle diameter). The average diameter of the insulating material is determined using a particle size distribution measuring device or the like. (Conductive material) The conductive material of the present invention contains the aforementioned conductive particles and a binder resin. The above-mentioned conductive particles are preferably dispersed in a binder resin and used as a conductive material. The aforementioned conductive material is preferably an anisotropic conductive material. The conductive particles and the conductive material are preferably used for electrical connection between electrodes, respectively. The aforementioned conductive material is preferably a material for circuit connection. The above-mentioned binder resin is not particularly limited. A well-known insulating resin can be used as the above-mentioned binder resin. 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, for example. As said thermoplastic resin, polyolefin resin, an ethylene-vinyl acetate copolymer, a polyamide resin, etc. are mentioned, for example. As said curable resin, epoxy resin, urethane resin, polyimide resin, unsaturated polyester resin, etc. are mentioned, for example. In addition, 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, and styrene-butadiene-styrene block copolymers. The hydrogenated product of block copolymer, and the hydrogenated product of styrene-isoprene-styrene block copolymer, etc. As said elastomer, a styrene-butadiene copolymer rubber, an acrylonitrile-styrene block copolymer rubber, etc. are mentioned, for example. The conductive material and the binder resin preferably contain a thermoplastic component or a thermosetting component. The conductive material and the binder resin may include a thermoplastic component or a thermosetting component. The conductive material and the binder resin preferably contain a thermosetting component. The above-mentioned thermosetting component preferably contains a curable compound that can be hardened by heating and a thermosetting agent. The thermal hardening agent is preferably a thermal cationic hardening initiator. The above-mentioned curable compound which can be hardened by heating and the above-mentioned thermosetting agent are used in an appropriate mixing ratio in such a way that the above-mentioned binder resin is hardened. If the above-mentioned binder resin contains a thermal cationic curing initiator, it is easy to contain an acid in the cured product. However, by using the conductive particles of the present invention, the connection resistance between the electrodes can be maintained low. In addition to the conductive particles and the binder resin, the conductive material may also include fillers, extenders, softeners, plasticizers, polymerization catalysts, curing catalysts, colorants, antioxidants, and heat stabilizers. , Light stabilizers, UV absorbers, lubricants, antistatic agents and flame retardants and other additives. The aforementioned conductive materials can be used as conductive pastes, conductive films, and the like. When the above-mentioned conductive material is a conductive film, a film containing no conductive particles may be laminated on the conductive film containing 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 It is 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, the conductive particles can be efficiently arranged between the electrodes, and the connection reliability of the connection object members 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, and preferably 80% by weight or less, more preferably 60% by weight or less, and more preferably It is 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 reliability of conduction between electrodes can be further improved. (Connection structure) A connection structure can be obtained by connecting the connection object member using the said electroconductive particle, or the said electroconductive material containing the said electroconductive particle and a binder resin. The above-mentioned connection structure is preferably a connection structure comprising a first connection object member, a second connection object member, and a connecting portion connecting the first and second connection object members, and the material of the connection portion is the present invention Or the conductive material of the present invention comprising the conductive particles and a binder resin. The above-mentioned connection part is preferably formed of the conductive particles of the present invention or formed of the conductive material of the present invention containing the conductive particles and a binder resin. In the case of using conductive particles, the connection portion itself is conductive particles. That is, the first and second connection target members are connected by the above-mentioned conductive particles. In Fig. 5, a front cross-sectional view schematically shows 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, the conductive particles 11, 21, etc. 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 a method of manufacturing the above-mentioned connection structure, a method of disposing the conductive material between the first connection object member and the second connection object member to obtain a laminate, and then heating the laminate And pressurization. The above-mentioned pressurization pressure is about 9.8×10 ⁴ to 4.9×10 ⁶ Pa. The above heating temperature is about 120-220°C. Specific examples of the connection target member include electronic components such as semiconductor wafers, capacitors, and diodes; and circuit boards such as printed circuit boards, flexible printed circuit boards, epoxy glass substrates, and glass substrates. The connection target member is preferably an electronic component. The above-mentioned conductive particles are preferably used for electrical connection of electrodes in electronic parts. Examples of the electrodes provided on the above-mentioned connection target member include metals such as gold electrodes, nickel electrodes, tin electrodes, aluminum electrodes, copper electrodes, silver electrodes, SUS (Steel Use Stainless, Japanese stainless steel standards) electrodes, molybdenum electrodes, and tungsten electrodes. electrode. When the connection object member is a flexible printed circuit board, the electrode is preferably a gold electrode, a nickel electrode, a tin 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, or a tungsten electrode. Furthermore, when the above-mentioned electrode is an aluminum electrode, it may be an electrode formed only of aluminum, or may be an electrode in which aluminum is laminated on the surface of a metal oxide layer. Examples of the material of the metal oxide layer include indium oxide doped with trivalent metal elements, zinc oxide doped with trivalent metal elements, and the like. 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) Divinylbenzene copolymer resin particles (base material particle A, "Micropearl SP-203" manufactured by Sekisui Chemical Industry Co., Ltd.) having a particle diameter of 3.0 μm were prepared. An ultrasonic disperser was used to disperse 10 parts by weight of the above-mentioned substrate particles A in 100 parts by weight of an alkali solution containing 5% by weight of a palladium catalyst solution, and then the substrate particles A were taken out by filtering the solution. Then, the substrate particle A was added to 100 parts by weight of a 1% by weight solution of dimethylamine borane to activate the surface of the substrate particle A. After the substrate particle A whose surface has been activated is sufficiently washed with water, it is added to 500 parts by weight of distilled water to disperse it, thereby obtaining a dispersion. Next, it took 3 minutes to add 2 g of Ni particle slurry (average particle size 150 nm) to the above dispersion to obtain a suspension (0) containing substrate particles with attached core material. Also, prepare a nickel plating solution (1) (pH 8.5) containing 0.14 mol/L of nickel sulfate, 0.46 mol/L of dimethylamine borane and 0.2 mol/L of sodium citrate as the nickel plating solution (1) . While stirring the obtained suspension (0) at 60°C, the above-mentioned nickel plating solution (1) was gradually added dropwise to the suspension to perform electroless nickel-boron alloy plating, thereby obtaining a suspension (1). Prepare a nickel plating solution containing 0.14 mol/L nickel sulfate, 0.03 mol/L sodium stannate trihydrate, 0.60 mol/L titanium chloride (III), and 0.15 mol/L sodium gluconate (2) (pH8.0) as the nickel plating solution (2). The temperature of the suspension (1) was set to 70°C, and the nickel plating solution (2) was gradually added dropwise to the suspension (1) to perform electroless nickel-tin alloy plating to obtain a suspension (2) . After that, the particles were taken out by filtering the suspension (2), washed with water, and dried, thereby disposing a conductive layer (thickness 0.1 μm) containing nickel on the surface of the substrate particle A, thereby obtaining a conductive layer on the surface The conductive particles. (Example 2) The 0.03 mol/L sodium stannate trihydrate of the nickel plating solution (2) was changed to 0.04 mol/L indium (III) acetate, except that it was obtained in the same manner as in Example 1 Conductive particles. (Example 3) Except having changed the Ni particle slurry to the alumina particle slurry, it carried out similarly to Example 1, and obtained electroconductive particle. (Example 4) For the formation of protrusions, the Ni particle paste was not used, and adjustments were made by partially changing the precipitation amount when forming the conductive part to form protrusions. Except for this, the conductivity was obtained in the same manner as in Example 1. Sex particles. (Example 5) The 0.60 mol/L titanium chloride (III) of the nickel plating solution (2) was changed to 0.46 mol/L dimethylamine borane, except that it was obtained in the same manner as in Example 1 Conductive particles. (Example 6) The 0.46 mol/L dimethylamine borane of the nickel plating solution (1) was changed to 1.40 mol/L sodium hypophosphite, and the nickel plating solution (2) was chlorinated at 0.60 mol/L Except that titanium (III) was changed to 1.40 mol/L sodium hypophosphite, conductive particles were obtained in the same manner as in Example 1. (Example 7) The 0.46 mol/L dimethylamine borane of the nickel plating solution (1) was changed to 0.60 mol/L titanium(III) chloride, except that it was obtained in the same manner as in Example 1 Conductive particles. (Example 8) To the nickel plating solution (1), 0.02 mol/L of sodium stannate trihydrate and 0.10 mol/L of sodium gluconate were added, except that the conductivity was obtained in the same manner as in Example 1 particle. (Example 9) To the nickel plating solution (1), 0.04 mol/L of sodium stannate trihydrate and 0.20 mol/L of sodium gluconate were added, except that conductive particles were obtained in the same manner as in Example 1. . (Example 10) The addition amount of sodium stannate trihydrate in the nickel plating solution (2) was changed from 0.03 mol/L to 0.05 mol/L, and the addition amount of sodium gluconate in the nickel plating solution (2) was changed from Except for changing 0.15 mol/L to 0.25 mol/L, conductive particles were obtained in the same manner as in Example 1. (Example 11) Add 0.04 mol/L of sodium stannate trihydrate and 0.20 mol/L of sodium gluconate to nickel plating solution (1), and combine the sodium stannate trihydrate of nickel plating solution (2) The addition amount was changed from 0.03 mol/L to 0.05 mol/L, and the addition amount of sodium gluconate in the nickel plating solution (2) was changed from 0.15 mol/L to 0.25 mol/L. Otherwise, the same as in Example 1. In the same way, conductive particles are obtained. (Example 12) The addition amount of sodium stannate trihydrate in the nickel plating solution (2) was changed from 0.03 mol/L to 0.02 mol/L, and 0.02 mol/L of acetic acid was added to the nickel plating solution (2) Except for indium (III), conductive particles were obtained in the same manner as in Example 1. (Example 13) The composition of the nickel plating solution (1) (pH 8.5) was changed to 0.18 mol/L nickel sulfate, 0.66 mol/L dimethylamine borane, and 0.25 mol/L sodium citrate. The composition of the nickel plating bath (2) (pH 8.0) is changed to 0.18 mol/L nickel sulfate, 0.04 mol/L sodium stannate trihydrate, 0.75 mol/L titanium(III) chloride, and 0.19 mol /L of sodium gluconate, and the thickness of the conductive layer was changed from 0.1 μm to 0.15 μm, except that the conductive particles were obtained in the same manner as in Example 1. (Example 14) The composition of the nickel plating solution (1) (pH 8.5) was changed to 0.07 mol/L nickel sulfate, 0.23 mol/L dimethylamine borane, and 0.10 mol/L sodium citrate. The composition of the nickel plating bath (2) (pH 8.0) was changed to 0.07 mol/L nickel sulfate, 0.02 mol/L sodium stannate trihydrate, 0.3 mol/L titanium(III) chloride, and 0.10 mol /L of sodium gluconate, and the thickness of the conductive layer was changed from 0.1 μm to 0.06 μm, except that the conductive particles were obtained in the same manner as in Example 1. (Example 15) Only the particle diameter is different from the above-mentioned substrate particle A, and the substrate particle B having a particle diameter of 2.2 μm was prepared. Except having changed the said substrate particle A into the said substrate particle B, it carried out similarly to Example 1, and obtained electroconductive particle. (Example 16) Only the particle diameter is different from the above-mentioned substrate particle A, and the substrate particle C having a particle diameter of 10.0 μm was prepared. Except having changed the said substrate particle A into the said substrate particle C, it carried out similarly to Example 1, and obtained electroconductive particle. (Example 17) Into a 500 mL reaction vessel equipped with a stirrer and a thermometer, 300 g of 0.13 wt% ammonia solution was placed. Secondly, slowly add 4.1 g of methyl trimethoxysilane, 19.2 g of vinyl trimethoxysilane, and 0.7 g of silicone alkoxy oligomer (manufactured by Shin-Etsu Chemical Co., Ltd.) to the ammonia solution in the reaction vessel. "X-41-1053") mixture. After stirring on one side, hydrolysis and condensation reaction on the other side, add 2.4 mL of 25 wt% ammonia solution, and then separate the particles from the ammonia solution. The obtained oxygen partial pressure is 10 ^-17 atm and 350℃. The particles were calcined for 2 hours to obtain organic-inorganic mixed particles (base material particles D) with a particle diameter of 3.0 μm. Except having changed the said substrate particle A into the said substrate particle D, it carried out similarly to Example 3, and obtained electroconductive particle. (Example 18) In 100% of the total surface area of the outer surface of the conductive part, the surface area of the part with protrusions was changed from 70% to 25%, except that the conductive particles were obtained in the same manner as in Example 1. (Example 19) In a 1000 mL separable flask equipped with a four-port separable cap, a stirring blade, a three-way stopcock, a cooling tube, and a temperature probe, the solid content ratio became 5 wt%. Contains 100 mmol of methyl methacrylate, 1 mmol of N,N,N-trimethyl-N-2-methacryloxyethyl ammonium chloride, and 1 mmol of 2,2'-azo The monomer composition of bis(2-amidinopropane) dihydrochloride is weighed into ion exchange water. Thereafter, stirring was carried out at 200 rpm, and polymerization was carried out at 70°C for 24 hours in a nitrogen atmosphere. After the reaction is completed, freeze-drying is performed to obtain insulating particles with an ammonium group on the surface, an average particle diameter of 220 nm and a CV value of 10%. Disperse the insulating particles in ion-exchanged water under ultrasonic irradiation to obtain a 10% by weight aqueous dispersion of insulating particles. Disperse 10 g of the conductive particles obtained in Example 1 in 500 mL of ion-exchange water, and add 4 g of an aqueous dispersion of insulating particles, and stir at room temperature for 6 hours. After filtering with a 3 μm mesh filter, it was further washed with methanol and dried to obtain conductive particles with insulating particles attached. Observation using a scanning electron microscope (SEM) showed that only one coating layer of insulating particles was formed on the surface of the conductive particles. The coverage area of the insulating particles with respect to the area of 2.5 μm from the center of the conductive particles (that is, the projected area of the particle diameter of the insulating particles) was calculated by image analysis. As a result, the coverage rate was 30%. (Comparative Example 1) The addition amount of sodium stannate trihydrate in the nickel plating solution (2) was changed from 0.03 mol/L to 0.10 mol/L, and the addition amount of sodium gluconate in the nickel plating solution (2) was changed from Except for changing 0.15 mol/L to 0.35 mol/L, in the same manner as in Example 1, conductive particles were obtained. (Comparative Example 2) Add 0.04 mol/L of sodium stannate trihydrate and 0.20 mol/L of sodium gluconate to the nickel plating solution (1), except that the conductivity was obtained in the same manner as in Comparative Example 1 particle. (Evaluation) (1) The average content of nickel, tin, and indium in the entire conductive layer containing nickel Add 5 g of conductive particles to a mixture of 5 mL of 60% nitric acid and 10 mL of 37% hydrochloric acid to make The conductive layer is completely dissolved and a solution is obtained. Using the obtained solution, a high-frequency inductively coupled plasma ion source mass spectrometer (“ICP-MS” manufactured by Hitachi, Ltd.) was used to analyze the contents of nickel, tin, and indium. Furthermore, the content other than nickel, tin and indium is phosphorus or boron. (2) The average content of nickel, tin, and indium in the thickness direction of the conductive layer containing nickel is measured for the distribution of the content of nickel, tin, and indium in the thickness direction of the conductive layer containing nickel. Using a focused ion beam, a thin film slice of the obtained conductive particles is made. Using an electric field radiation type transmission electron microscope ("JEM-2010FEF" manufactured by JEOL Ltd.), using an energy dispersive X-ray analyzer (EDS) to analyze the thickness of nickel, tin and indium of the conductive layer containing nickel The content is determined. Based on the results, the above-mentioned region (R1) of the thickness of 1/2 from the inner surface of the conductive layer containing nickel to the outside (the region of thickness 50% on the inner surface side), and the outer surface of the conductive layer containing nickel The above-mentioned region (R2) from the inner side to the thickness of 1/2 (the region of 50% thickness on the outer surface side), and the above-mentioned region (R3) from the outer surface to the inner side of the thickness 1/4 of the conductive layer containing nickel ( The area of 25% thickness on the outer surface side), and the above-mentioned area (R4) between the position of the thickness 1/4 from the outer surface to the inner side of the conductive layer containing nickel and the position of the thickness 1/2 (from the outer The surface side is the average content of nickel, tin, and indium in the area from the position of 25% thickness to the position of 50% thickness. Furthermore, the content other than nickel, tin and indium is phosphorus or boron. In addition, by the above measurement, the distribution results of the contents of nickel, tin, and indium in the thickness direction of the conductive layer containing nickel are obtained. Based on this result, the maximum value of the total content of tin and indium in the above region (R3) is obtained. (3) The melting point of the conductive layer of the conductive particles was measured using a differential scanning calorimeter ("DSC-6300" manufactured by Yamato Scientific). As a result, the melting point of the conductive layer in the example was 300°C or higher. (4) 10% K value of conductive particles The 10% K value of the obtained conductive particles was measured using a micro compression tester ("Fischerscope H-100" manufactured by Fischer). (5) The volume resistivity of the conductive particles was measured using the "Powder Resistivity Measurement System" manufactured by Mitsubishi Chemical Corporation to measure the volume resistivity of the obtained conductive particles. (6) Connection resistance A (initial stage) Connection structure production: 20 parts by weight of epoxy compound ("EP-3300P" manufactured by Nagase chemteX Corporation.) as a thermosetting compound, and 15 parts by weight as thermosetting Epoxy compound ("EPICLON HP-4032D" manufactured by DIC), 5 parts by weight of thermal cation generator (San-Aid "SI-60" manufactured by Sanshin Chemical Company) as a thermal hardening agent, and 20 parts by weight of silica as filler (average particle size 0.25 μm), and then add the obtained conductive particles so that the content in 100% by weight of the formulation becomes 10% by weight, and then stir at 2000 rpm with a planetary mixer 5 minutes, thereby obtaining an anisotropic conductive paste. Prepare a glass substrate with an Al-Ti 4% electrode pattern (Al-Ti 4% electrode thickness of 1 μm) with L/S of 20 μm/20 μm on the upper surface. In addition, a semiconductor wafer having a gold electrode pattern (gold electrode thickness 20 μm) with L/S of 20 μm/20 μm on the lower surface was prepared. The anisotropic conductive paste immediately after production was applied to the upper surface of the glass substrate to form a thickness of 20 μm to form an anisotropic conductive material layer. Next, the above-mentioned semiconductor wafer is laminated on the upper surface of the anisotropic conductive material layer with the electrodes facing each other. After that, while adjusting the temperature of the head so that the temperature of the anisotropic conductive material layer becomes 170°C, the pressure heating head is placed on the upper surface of the semiconductor wafer, and a pressure of 2.5 MPa is applied at 170°C. The anisotropic conductive material layer is hardened to obtain a connection structure. Measurement of connection resistance: Use the four-terminal method to measure the connection resistance A between the opposite electrodes of the obtained connection structure. In addition, the connection resistance A was determined based on the following criteria. [Evaluation criteria for connection resistance A] 〇〇〇: Connection resistance A is 2.0 Ω or less 〇〇〇: Connection resistance A exceeds 2.0 Ω and is 3.0 Ω or less 〇: Connection resistance A exceeds 3.0 Ω and is 5.0 Ω or less △: Connection resistance A exceeds 5.0 Ω and is 10 Ω or less ×: Connection resistance A exceeds 10 Ω (7) Connection resistance B (after the influence of acid) Immerse the obtained conductive particles in a 5% sulfuric acid aqueous solution for 30 minutes. After that, the particles were taken out by filtration, washed with water, and replaced with ethanol, and allowed to stand for 10 minutes to dry the particles, thereby obtaining conductive particles exposed to acid. Using the obtained conductive particles, a connection structure was produced in the same manner as in (6) above, and the connection resistance B was measured in the same manner as the connection resistance A. In addition, the connection resistance B was determined based on the following criteria. [Evaluation criteria for connection resistance B] 〇〇〇: Connection resistance B is more than 1 time and less than 1.5 times the connection resistance A 〇〇: Connection resistance B is more than 1.5 times and less than 2 times the connection resistance A 〇: Connection Resistance B is more than 2 times and less than 5 times the connecting resistance A △: Connecting resistance B is more than 5 times and less than 10 times the connecting resistance A ×: Connecting resistance B is more than 10 times the connecting resistance A (8) Connection Resistance C (after the influence of alkali) The obtained conductive particles are immersed in a 5% sodium hydroxide aqueous solution for 30 minutes. After that, the particles were taken out by filtration, washed with water, and replaced with ethanol and allowed to stand for 10 minutes to dry the particles, thereby obtaining conductive particles exposed to alkali. Using the obtained conductive particles, a connection structure was produced in the same manner as in (6) above, and the connection resistance C was measured in the same manner as the connection resistance A. In addition, the connection resistance C was determined based on the following criteria. [Evaluation criteria for connection resistance C] 〇〇〇: Connection resistance C is more than 1 time and less than 1.5 times the connection resistance A 〇〇: Connection resistance C is more than 1.5 times and less than 2 times the connection resistance A 〇: Connection Resistance C is more than 2 times and less than 5 times the connection resistance A △: Connection resistance C is more than 5 times and less than 10 times the connection resistance A ×: Connection resistance C is more than 10 times the connection resistance A (9) Condensation State: 10 parts by weight of bisphenol A epoxy resin ("Epikote 1009" manufactured by Mitsubishi Chemical Corporation), 40 parts by weight of acrylic rubber (weight average molecular weight approximately 800,000), and 200 parts by weight of methyl ethyl ketone , 50 parts by weight of microcapsule hardener ("HX3941HP" manufactured by Asahi Kasei Chemical Co., Ltd.), and 2 parts by weight of silane coupling agent ("SH6040" manufactured by Toray Dow Corning Polysiloxane) are mixed, and the content becomes 3 weight Add conductive particles and disperse them to obtain an anisotropic conductive material. In addition, as the conductive particles, particles of the three conditions used in connection resistance A, connection resistance B, and connection resistance C were used to produce three types of anisotropic conductive materials. The three anisotropic conductive materials obtained were stored at 25°C for 72 hours. After storage, it was evaluated whether or not the conductive particles aggregated in the anisotropic conductive material had precipitated. Determine the aggregation state according to the following criteria. [Criteria for determination of aggregation state] ○: In all three anisotropic conductive materials, the aggregated conductive particles are not precipitated △: Only in one anisotropic conductive material, the aggregated conductive particles are precipitated ×: In In two or more anisotropic conductive materials, the aggregated conductive particles precipitated. The results are shown in Tables 1 to 3 below. [Table 1]

[Table 2]

[table 3]

1‧‧‧Conductive particles 2‧‧‧Substrate particles 3‧‧‧Conductive layer containing nickel 11‧‧‧Conductive particles 11a‧‧‧Protrusion 12‧‧‧Conductive layer containing nickel 12a‧‧‧Protrusion 13 ‧‧‧Core material 14‧‧‧Insulating material 21‧‧‧Conductive particle 21a‧‧‧Protrusion 22‧‧‧Conductive layer 22a‧‧‧Containing nickel 22A‧‧‧Protrusion 22A‧‧‧First conductive layer 22Aa‧‧‧ Protrusion 22B‧‧‧Second conductive layer 22Ba‧‧‧Protrusion 51‧‧‧Connection structure 52‧‧‧First connection object member 52a‧‧‧First electrode 53‧‧‧Second connection object member 53a‧‧‧ The second electrode 54‧‧‧Connecting part L1‧‧‧Dotted line L2‧‧‧Dotted line R1‧‧‧Region R2‧‧‧Region R3‧‧‧Region R4‧‧‧Region

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. 4(a) and (b) are schematic diagrams for explaining each area where the total average content of tin and indium in a conductive layer containing nickel is obtained. 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.

1‧‧‧Conductive particles

2‧‧‧Substrate particles

3‧‧‧Conducting layer containing nickel

Claims (9)

A conductive particle comprising a substrate particle and a conductive layer containing nickel arranged on the surface of the substrate particle, and the conductive layer containing nickel is an alloy containing at least one of nickel and tin and indium Layer, in 100% by weight of the area from the outer surface of the conductive layer containing nickel to the inner side to the thickness 1/2, the total average content of tin and indium is less than 5% by weight. The conductive particle of claim 1, wherein the total average content of tin and indium in the region from the outer surface of the conductive layer containing nickel to the inner side to the thickness of 1/4 is greater than the distance of the conductive layer containing nickel The total average content of tin and indium in the region from the position where the thickness is 1/4 to the position where the thickness is 1/2 toward the inner surface is large. The conductive particles according to claim 1 or 2, wherein the maximum value of the total content of tin and indium in 100% by weight of the area from the outer surface to the inner side of the thickness 1/4 of the thickness of the conductive layer containing nickel is 50 Weight% or less. The conductive particle of claim 1 or 2, wherein the conductive layer containing nickel has protrusions on the outer surface. For example, the conductive particles of claim 1 or 2 have a volume resistivity of 0.003 Ω·cm or less. The conductive particles of claim 1 or 2, wherein the total average content of tin and indium in 100% by weight of the area from the inner surface to the outside of the thickness 1/2 of the conductive layer containing nickel is less than 5 weight %. The conductive particles according to claim 1 or 2, further comprising an insulating substance arranged on the outer surface of the conductive layer containing nickel. A conductive material comprising the conductive particles according to any one of claims 1 to 7 and a binder resin. A connection structure comprising: a first connection object member; a second connection object member; and a connecting portion that connects the first connection object member and the second connection object member; and the material of the connection portion is as requested The conductive particles of any one of items 1 to 7, or a conductive material containing the conductive particles and a binder resin.

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