KR20140106385A - Conductive particles, conductive material, and connection structure - Google Patents

Abstract

The present invention provides a conductive particle capable of lowering the connection resistance between electrodes and suppressing an increase in connection resistance under high temperature and high humidity when the connection structure is obtained by connecting the electrodes. The conductive particles (1) according to the present invention have base particles (2) and conductive layers (3) arranged on the surface of the base particles (2). The conductive layer 3 comprises at least one metal component selected from the group consisting of nickel, tungsten and molybdenum. The content of nickel in the entire 100 wt% of the conductive layer 3 is 60 wt% or more. The total content of tungsten and molybdenum in 100 wt% of the conductive layer portion 5 nm thick inward from the outer surface of the conductive layer 3 in the thickness direction exceeds 5 wt%.

Description

TECHNICAL FIELD [0001] The present invention relates to conductive particles, conductive materials, and connection structures,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to conductive particles in which conductive layers are disposed on the surface of base particles, and more particularly to conductive particles which can be used for electrical connection between electrodes, for example. The present invention also relates to a conductive material and a connection structure using the conductive particles.

Anisotropic conductive paste such as anisotropic conductive paste and anisotropic conductive film are widely known. In the anisotropic conductive material, the conductive particles are dispersed in the binder resin.

The anisotropic conductive material is used for connection between the IC chip and the flexible printed circuit board and for connection between the IC chip and the circuit board having the ITO electrode. For example, after the anisotropic conductive material is disposed between the electrodes of the IC chip and the electrodes of the circuit board, these electrodes can be electrically connected by heating and pressing.

As an example of the above conductive particles, Patent Document 1 below discloses a conductive particle in which a nickel conductive layer or a nickel alloy conductive layer is formed on the surface of spherical base particles having an average particle diameter of 1 to 20 占 퐉 by electroless plating, . The conductive particles have minute projections of 0.05 to 4 占 퐉 in the outermost layer of the conductive layer. The conductive layer and the protrusions are connected substantially continuously.

Japanese Patent Application Laid-Open No. 2000-243132

When the electrodes are connected using the conductive particles described in Patent Document 1, the connection resistance between the electrodes may be increased. In the embodiment of Patent Document 1, a conductive layer including nickel and phosphorus is formed. There are many cases where an oxide film is formed on the surface of the conductive layer of the electrode and the conductive particles which are connected by the conductive particles. When the electrodes are connected using the conductive particles having a conductive layer containing nickel and phosphorus, since the conductive layer containing nickel and phosphorus is relatively soft, it is possible to sufficiently remove the oxide film on the surfaces of the electrodes and the conductive particles There is a case where the connection resistance is increased.

Further, in order to lower the connection resistance, if the thickness of the conductive layer including nickel and phosphorus as described in Patent Document 1 is made thick, the member to be connected or the substrate may be scratched by the conductive particles.

In addition, the connection structure in which the electrodes are connected by the conductive particles may be exposed under high temperature and high humidity. In the conventional conductive particles as described in Patent Document 1, the conductive layer is denatured under the influence of an acid or the like under high temperature and high humidity, and the connection resistance between the electrodes is increased in some cases. That is, when the connection structure is exposed under high temperature and high humidity, the connection resistance between the electrodes may be increased, and a low connection resistance may not be maintained for a long period of time.

An object of the present invention is to provide a conductive particle capable of lowering the connection resistance between electrodes when the connection structure is obtained by connecting the electrodes to each other and further suppressing an increase in connection resistance under high temperature and high humidity, And to provide a conductive material and a connection structure which are used.

According to a broad aspect of the present invention, there is provided a semiconductor device comprising: base particles; and a conductive layer disposed on a surface of the base particles, wherein the conductive layer includes at least one metal component selected from the group consisting of nickel, tungsten, and molybdenum, Wherein the total content of tungsten and molybdenum in 100 wt% of the conductive layer portion having a thickness of 5 nm from the outer surface of the conductive layer toward the inner side in the thickness direction is 5 wt% % ≪ / RTI >

In a specific aspect of the conductive particles according to the present invention, the total content of tungsten and molybdenum in 100 wt% of the conductive layer portion having a thickness of 5 nm inward from the outer surface of the conductive layer in the thickness direction is 10 wt% or more .

In another specific aspect of the conductive particle according to the present invention, at least one of the metal components of nickel, tungsten, and molybdenum is localized in the thickness direction of the conductive layer, and the outer portion of the conductive layer is located inside the conductive layer Part of the metal component.

In another specific aspect of the conductive particles according to the present invention, the total content of tungsten and molybdenum in the total 100 wt% of the conductive layer exceeds 5 wt%.

It is preferable that the nickel ion concentration eluted when immersing 10 parts by weight of the plurality of conductive particles according to the present invention in 100 parts by weight of 5 wt% citric acid aqueous solution at 25 캜 for 1 minute is not more than 100 ppm / cm 2 per unit surface area of the conductive particles.

In another specific aspect of the conductive particles according to the present invention, the conductive layer is formed by electroless nickel plating using a reducing agent, and the conductive layer does not contain a component derived from the reducing agent, And the content of the component derived from the reducing agent in the entire 100 wt% of the conductive layer is 5 wt% or less.

In another specific aspect of the conductive particles according to the present invention, the conductive layer comprises boron. The content of boron in 100 wt% of the entire conductive layer is preferably 0.05 wt% or more and 4 wt% or less.

In another specific aspect of the conductive particles according to the present invention, the conductive layer does not contain phosphorus, or the conductive layer contains phosphorus and the content of phosphorus in the entire 100 wt% of the conductive layer is less than 0.5 wt%.

In another specific aspect of the conductive particles according to the present invention, the conductive layer has projections on the outer surface.

The conductive material according to the present invention includes the above-described conductive particles and a binder resin.

The connecting structure according to the present invention includes a first connecting object member, a second connecting object member, and a connecting portion connecting the first and second connecting object members, wherein the connecting portion is formed by the above- Or formed of a conductive material containing the conductive particles and a binder resin.

In the conductive particle according to the present invention, the conductive layer is disposed on the surface of the base particle, and the conductive layer contains at least one metal component selected from the group consisting of nickel, tungsten, and molybdenum, The content of nickel is 60% by weight or more and the total content of tungsten and molybdenum in 100% by weight of the conductive layer portion having a thickness of 5 nm inward from the outer surface of the conductive layer in the thickness direction exceeds 5% by weight , And when the connection structure is obtained by connecting the electrodes using the conductive particles according to the present invention, the connection resistance between the electrodes can be reduced. Further, even if the connection structure is exposed under high temperature and high humidity, the connection resistance is difficult to increase.

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

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

The conductive particles according to the present invention have base particles and a conductive layer disposed on the surface of the base particles. The conductive layer includes at least one metal component selected from the group consisting of nickel, tungsten, and molybdenum. The content of nickel in 100 wt% of the entire conductive layer is 60 wt% or more. The total content of tungsten and molybdenum in 100 wt% of the conductive layer portion having a thickness of 5 nm inward from the outer surface of the conductive layer in the thickness direction exceeds 5 wt%.

In the conductive particles according to the present invention, since the conductive layer has the above specific composition, when the conductive particles according to the present invention are used for connection between the electrodes, the connection resistance between the electrodes can be reduced. In addition, the conductive layer having a specific composition described above is relatively hard. Therefore, even when the electrodes and the oxide film on the surfaces of the conductive particles can be effectively removed at the time of connection between the electrodes, the connection resistance between the electrodes becomes low.

Further, in the conductive particle according to the present invention, the total content of tungsten and molybdenum in the vicinity of the outer surface is relatively large. For this reason, for example, the acid resistance of the conductive layer becomes high. Therefore, even if the connection structure is exposed under high temperature and high humidity, the influence of the acid or the like is reduced. As a result, the connection resistance between the electrodes hardly rises, and a low connection resistance can be maintained for a long period of time.

In contrast, if the content of tungsten and molybdenum in the total of 100 wt% of the conductive layer portion 5 nm in thickness from the outer surface of the conductive layer toward the inner side in the thickness direction is 5 wt% or less, When exposed, the connection resistance between the electrodes gradually increases.

The total content of tungsten and molybdenum in 100 wt% of the conductive layer portion having a thickness of 5 nm from the outer surface of the conductive layer toward the inside in the thickness direction is the more the better. Therefore, the total content of tungsten and molybdenum in 100 wt% of the conductive layer portion having a thickness of 5 nm from the outer surface of the conductive layer toward the inside in the thickness direction is preferably at least 10 wt%, more preferably at least 15 wt% More preferably not less than 20% by weight, particularly preferably not less than 25% by weight, and most preferably not less than 30% by weight. From the viewpoint of further lowering the initial connection resistance, the total content of tungsten and molybdenum in 100 wt% of the conductive layer portion having a thickness of 5 nm inward from the outer surface of the conductive layer in the thickness direction is preferably 60 wt% Or less, more preferably 50 wt% or less, and further preferably 40 wt% or less.

It is preferable that at least one of the metal components of nickel, tungsten and molybdenum is localized in the thickness direction of the conductive layer and that the outer portion of the conductive layer contains a larger amount of the metal component than the inner portion of the conductive layer . In this case, the initial connection resistance between the electrodes can be effectively lowered, and the rise of the connection resistance under high temperature and high humidity can be further effectively suppressed. The outer portion of the conductive layer is preferably a conductive layer portion having a thickness of 5 nm from the outer surface of the conductive layer inward in the thickness direction. The inner portion of the conductive layer is preferably an inner portion of the conductive layer portion having a thickness of 5 nm inward from the outer surface of the conductive layer in the thickness direction. In the conductive particles according to the present invention, the content of the metal component may not have a concentration gradient in the entire conductive layer. In the entire conductive layer, the content of the metal component may be substantially uniform. Therefore, the total content of tungsten and molybdenum may exceed 5 wt% in all the conductive layer portions.

It is preferable that the nickel ion concentration eluted when immersing 10 parts by weight of the plurality of conductive particles according to the present invention in 100 parts by weight of 5 wt% citric acid aqueous solution at 25 캜 for 1 minute is 100 ppm / cm 2 or less per unit surface area of the conductive particles. In this case, the connection resistance between the electrodes is effectively lowered, and the current capacity capable of withstanding the conductive particles in contact with the electrodes is further increased.

Wherein the conductive layer is formed by electroless nickel plating using a reducing agent and the conductive layer does not contain a component derived from the reducing agent or contains a component derived from the reducing agent, The content of the component derived from the reducing agent is preferably 5% by weight or less. In this case, the connection resistance between the electrodes can be effectively lowered, and the rise of the connection resistance under high temperature and high humidity can be effectively suppressed. The content of the component derived from the reducing agent in 100 wt% of the total of the conductive layer is more preferably 4 wt% or less, still more preferably 3 wt% or less, still more preferably 1 wt% By weight or less, most preferably 0.1% by weight or less.

Examples of the component derived from the reducing agent include phosphorus and boron. The reducing agent is preferably a phosphorus-containing reducing agent or a boron-containing reducing agent, and more preferably a boron-containing reducing agent. The component derived from the reducing agent is preferably phosphorus or boron, and more preferably boron.

Hereinafter, the present invention will be clarified by explaining specific embodiments and examples of the present invention with reference to the drawings.

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

As shown in Fig. 1, the conductive particles 1 have base particles 2, a conductive layer 3, a plurality of core materials 4, and a plurality of insulating materials 5.

The conductive layer 3 is disposed on the surface of the base particle 2. The conductive particle (1) is a coated particle in which the surface of the base particle (2) is covered with the conductive layer (3).

)되어 있다. 코어 물질 (4)는 돌기 (1a,3a)의 내측에 배치되어 있다. 도전층 (3)은 복수의 코어 물질 (4)를 피복하고 있다. 복수의 코어 물질 (4)에 의해 도전층 (3)의 외표면이 융기되어 있고, 돌기 (1a,3a)가 형성되어 있다.The conductive particles (1) have a plurality of projections (1a) on its surface. The conductive layer 3 has a plurality of projections 3a on its outer surface. A plurality of core materials (4) are arranged on the surface of the base particles (2). The plurality of core materials 4 are embedded in the conductive layer 3

). The core material 4 is disposed inside the projections 1a and 3a. The conductive layer 3 covers a plurality of core materials 4. The outer surface of the conductive layer 3 is raised by the plurality of core materials 4 and the projections 1a and 3a are formed.

The conductive particles (1) have an insulating material (5) arranged on the outer surface of the conductive layer (3). At least a part of the outer surface of the conductive layer (3) is covered with an insulating material (5). The insulating material 5 is formed of a material having an insulating property and is insulating particles. As such, the conductive particles according to the present invention may have an insulating material disposed on the outer surface of the conductive layer. However, the conductive particles according to the present invention may not necessarily contain an insulating material.

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

The conductive particles 11 shown in Fig. 2 include base particles 2, a second conductive layer 12 (another conductive layer), a conductive layer 13 (first conductive layer), a plurality of core materials 4 , And a plurality of insulating materials (5).

In the conductive particles (1) and the conductive particles (11), only the conductive layer is different. That is, in the conductive particles 1, a conductive layer having a one-layer structure is formed, whereas in the conductive particles 11, a second conductive layer 12 and a conductive layer 13 having a two-layer structure are formed.

The conductive layer 13 is disposed on the surface of the base particle 2. And a second conductive layer 12 (another conductive layer) is disposed between the base particles 2 and the conductive layer 13. [ Therefore, the second conductive layer 12 is disposed on the surface of the substrate particle 2, and the conductive layer 13 is disposed on the surface of the second conductive layer 12. The conductive layer 13 has a plurality of projections 13a on its outer surface. The conductive particles 11 have a plurality of projections 11a on their surfaces.

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

The conductive particles 21 shown in Fig. 3 have the base particles 2 and the conductive layer 22. The conductive layer 22 is disposed on the surface of the base particle 2.

The conductive particles 21 do not have a core material. The conductive particles 21 have no projections on the surface. The conductive particles 21 are spherical. The conductive layer 22 has no projections on its surface. As described above, the conductive particles according to the present invention may not have protrusions or may be spherical. Further, the conductive particles 21 have no insulating material. However, the conductive particles 21 may have an insulating material disposed on the surface of the conductive layer 22.

[Substrate Particle]

Examples of the base particles include resin particles, inorganic particles other than metals, organic-inorganic hybrid particles and metal particles. The base particles are preferably base particles excluding metal particles, more preferably resin particles, inorganic particles other than metal, or organic-inorganic hybrid particles.

The base particles are preferably resin particles formed by a resin. When the electrodes are connected using the conductive particles, the conductive particles are disposed between the electrodes and then compressed to compress the conductive particles. When the base particles are resin particles, the conductive particles are liable to be deformed at the time of pressing, and the contact area between the conductive particles and the electrode is increased. Therefore, the conduction reliability between the electrodes is improved.

As the resin for forming the resin particles, various organic materials are preferably used. Examples of the resin for forming the resin particles include polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polypropylene, polyisobutylene, and polybutadiene; Acrylic resins such as polymethyl methacrylate and polymethyl acrylate; But are not limited to, polyalkylene terephthalate, polycarbonate, polyamide, phenol formaldehyde resin, melamine formaldehyde resin, benzoguanamine formaldehyde resin, urea formaldehyde resin, phenol resin, melamine resin, benzoguanamine resin, urea resin, A variety of polymerizable monomers having an epoxy resin, an unsaturated polyester resin, a saturated polyester resin, polysulfone, polyphenylene oxide, polyacetal, polyimide, polyamideimide, polyetheretherketone, polyether sulfone, , And polymers obtained by polymerizing two or more of them. It is possible to design and synthesize resin particles having physical properties at the time of compression appropriate for the conductive material and to control the hardness of the base particles to a desired range with ease. Therefore, the resin for forming the resin particles is preferably an ethylenically unsaturated Is preferably a polymer obtained by polymerizing one or more polymerizable monomers having a plurality of groups.

When the resin particles are obtained by polymerizing a monomer having an ethylenic unsaturated group, examples of the monomer having an ethylenic unsaturated group include a monomer which is incompatible with the monomer and a monomer which is crosslinkable.

Examples of the non-crosslinkable monomer include styrene-based monomers such as styrene and? -Methylstyrene; Carboxyl group-containing monomers such as (meth) acrylic acid, maleic acid, and maleic anhydride; (Meth) acrylate, ethyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl Alkyl (meth) acrylates such as acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate and isobornyl (meth) acrylate; (Meth) acrylates such as 2-hydroxyethyl (meth) acrylate, glycerol (meth) acrylate, polyoxyethylene (meth) acrylate and glycidyl (meth) acrylate; Nitrile-containing monomers such as (meth) acrylonitrile; Vinyl ethers such as methyl vinyl ether, ethyl vinyl ether and propyl vinyl ether; Acid vinyl esters such as vinyl acetate, vinyl butyrate, vinyl laurate and vinyl stearate; Unsaturated hydrocarbons such as ethylene, propylene, isoprene and butadiene; Halogen-containing monomers such as trifluoromethyl (meth) acrylate, pentafluoroethyl (meth) acrylate, vinyl chloride, vinyl fluoride and chlorostyrene.

Examples of the crosslinkable monomer include tetramethylolmethane tetra (meth) acrylate, tetramethylol methane tri (meth) acrylate, tetramethylol methane di (meth) acrylate, trimethylolpropane tri (meth) (Meth) acrylate, dipentaerythritol penta (meth) acrylate, glycerol tri (meth) acrylate, glycerol di (meth) acrylate, (poly) ethylene glycol di Polyfunctional (meth) acrylates such as (poly) propylene glycol di (meth) acrylate, (poly) tetramethylene di (meth) acrylate and 1,4-butanediol di (meth) acrylate; (Meth) acryloxypropyltrimethoxysilane, trimethoxysilylstyrene, trimethylolpropane trimethoxysilane, triallyl trimellitate, divinyl benzene, diallyl phthalate, diallyl acrylamide, diallyl ether, , Silane-containing monomers such as vinyltrimethoxysilane, and the like.

The above-mentioned resin particles can be obtained by polymerizing the above-mentioned polymerizable monomer having an ethylenic unsaturated group by a known method. This method includes, for example, suspension polymerization in the presence of a radical polymerization initiator, and polymerization in which monomer is swollen together with radical polymerization initiator using non-crosslinked seed particles.

When the base particles are inorganic particles other than metal particles or organic-inorganic hybrid particles, examples of inorganic substances for forming the base particles include silica and carbon black. The particles formed by the silica are not particularly limited. For example, particles obtained by hydrolyzing a silicon compound having two or more hydrolyzable alkoxysilyl groups to form cross-linked polymer particles, followed by baking if necessary, . Examples of the organic-inorganic hybrid particles include organic-inorganic hybrid particles formed by a crosslinked alkoxysilyl polymer and an acrylic resin.

When the base particles are metal particles, examples of the metal for forming the metal particles include silver, copper, nickel, silicon, gold and titanium. However, it is preferable that the base particles are not metal particles.

The particle diameter of the base particles is preferably 0.1 μm or more, more preferably 0.5 μm or more, still more preferably 1 μm or more, still more preferably 1.5 μm or more, particularly preferably 2 μm or more, More preferably not more than 500 mu m, still more preferably not more than 300 mu m, further preferably not more than 50 mu m, further preferably not more than 30 mu m, particularly preferably not more than 5 mu m, 3 탆 or less. When the particle size of the base particles is not lower than the lower limit described above, the contact area between the conductive particles and the electrode becomes larger, so that the reliability of the conduction between the electrodes becomes further higher and the connection resistance between the electrodes connected via the conductive particles becomes further lower. Further, when the conductive layer is formed on the surface of the base particles by electroless plating, it is difficult to coagulate and the coagulated conductive particles are hardly formed. When the particle diameter is less than the upper limit, the conductive particles are easily compressed sufficiently, the connection resistance between the electrodes is further lowered, and the interval between the electrodes becomes smaller. The particle size of the base particles indicates a diameter when base particles are spherical, and indicates a maximum diameter when base particles are not spherical.

Particularly preferably, the particle size of the base particles is 0.1 占 퐉 or more and 5 占 퐉 or less. If the particle diameter of the base particles is within the range of 0.1 to 5 占 퐉, the distance between the electrodes becomes small, and even if the thickness of the conductive layer is increased, small conductive particles can be obtained. The particle size of the base particles is preferably 0.5 占 퐉 or more, more preferably 2 占 퐉 or more, more preferably 2 占 퐉 or more from the viewpoint of obtaining even smaller conductive particles even when the distance between the electrodes is further reduced or the thickness of the conductive layer is increased. , Preferably not more than 3 mu m.

[Conductive layer]

The conductive particles according to the present invention have a conductive layer disposed on the surface of the base particle. The conductive layer includes at least one metal component selected from the group consisting of nickel, tungsten, and molybdenum. Hereinafter, a conductive layer containing nickel and at least one metal component of tungsten and molybdenum may be referred to as a conductive layer X in some cases. The content of nickel in the entire 100 wt% of the conductive layer X is 60 wt% or more. The total content of tungsten and molybdenum in 100 wt% of the conductive layer portion having a thickness of 5 nm inward from the outer surface of the conductive layer X in the thickness direction exceeds 5 wt%.

The conductive layer X may be directly laminated on the surface of the base particle, or may be disposed on the surface of the base particle through another conductive layer or the like. Further, another conductive layer may be disposed on the surface of the conductive layer X. And the outer surface of the conductive particles is preferably the conductive layer X. By connecting the electrodes with the conductive particles having the conductive layer X on the outer surface, the connection resistance is sufficiently low.

From the viewpoint of effectively lowering the initial connection resistance between the electrodes, the content of the nickel in the entire 100 wt% of the conductive layer X is preferably as large as possible. Therefore, the content of the nickel in the entire 100 wt% of the conductive layer X is preferably 65 wt% or more, more preferably 70 wt% or more, still more preferably 75 wt% or more, still more preferably 80 wt% , Still more preferably not less than 85 wt%, particularly preferably not less than 90 wt%, and most preferably not less than 95 wt%. The content of nickel in the entire 100 wt% of the conductive layer X may be 97 wt% or more, 97.5 wt% or more, or 98 wt% or more.

The upper limit of the nickel content can be appropriately changed depending on the content of tungsten, molybdenum, boron, and the like. The content of nickel in the entire 100 wt% of the conductive layer X is preferably 99.85 wt% or less, more preferably 99.7 wt% or less, and still more preferably less than 99.45 wt%. When the content of nickel is lower than the lower limit, the connection resistance between the electrodes is further lowered. Further, when the surface of the electrode or the conductive layer has a small amount of the oxide film, the connection resistance between the electrodes tends to decrease as the content of nickel increases.

The conductive layer X includes at least one metal component selected from tungsten and molybdenum in addition to nickel. That is, the conductive layer X is a nickel-tungsten / molybdenum conductive layer containing at least one metal component selected from the group consisting of nickel, tungsten, and molybdenum. In the conductive layer X, nickel, at least one metal component of tungsten or molybdenum may be alloyed. In addition to tungsten and molybdenum, chromium and cyborgium may be used in the conductive layer X.

In the conductive particles having no conductive layer containing neither tungsten nor molybdenum, the nickel conductive layer containing neither tungsten nor molybdenum tends to have relatively low hardness at the initial stage of compression. Therefore, at the time of connection between the electrodes, the effect of excluding the oxide film on the surfaces of the electrodes and the conductive particles is reduced, and the connection resistance tends to be lowered.

On the other hand, if the thickness of the nickel electroconductive layer which does not include both tungsten and molybdenum is increased in order to further attain the effect of lowering the connection resistance or suitable for applications in which a large current flows, The substrate tends to be easily scratched. As a result, the reliability of conduction between the electrodes in the connection structure tends to be lowered.

On the other hand, by having the conductive particles X in the conductive particles, the connection resistance between the electrodes is effectively lowered. In addition, it is easy to cause the conductive layer X to have an appropriate crack. Cracks are generated when they are appropriately compressed, so that damage to the electrodes is less likely to occur, and thus the connection resistance between the electrodes is further lowered.

Further, since the conductive layer X has appropriate hardness, when the conductive particles are compressed to connect the electrodes, an appropriate indentation can be formed on the electrode. The indentations formed on the electrodes are concave portions of the electrodes generated by pressing the electrodes with the conductive particles.

The content (metal content) of tungsten and molybdenum in the entire 100 wt% of the conductive layer X is preferably 0.01 wt% or more, more preferably 0.1 wt% or more, still more preferably 0.2 wt% or more More preferably at least 0.5% by weight, even more preferably at least 1% by weight, particularly preferably at least 5% by weight and most preferably at least 10% by weight. When the total content of tungsten and molybdenum exceeds the above lower limit, the hardness of the outer surface of the conductive layer becomes higher. Therefore, when the oxide film is formed on the surface of the electrode or the conductive layer, it is possible to effectively eliminate the oxide film on the surface of the electrode and the conductive particle, to lower the connection resistance, and to increase the impact resistance of the resulting connection structure . If the total content of tungsten and molybdenum exceeds the lower limit described above, the magnetic properties of the outer surface of the conductive layer become weak, and the conductive particles become difficult to aggregate. Therefore, the short circuit between the electrodes can be effectively suppressed.

The upper limit of the total content of tungsten and molybdenum in the entire 100 wt% of the conductive layer X can be appropriately changed depending on the content of nickel, boron, and the like. The total content of tungsten and molybdenum in the entire 100 wt% of the conductive layer X is preferably 40 wt% or less, more preferably 30 wt% or less, further preferably 25 wt% or less, particularly preferably 20 wt% By weight or less.

The conductive layer X preferably contains boron in addition to nickel. The conductive layer X preferably includes at least one of nickel, tungsten, and molybdenum, and boron. That is, the conductive layer X is preferably a nickel-tungsten / molybdenum-boron conductive layer containing nickel, at least one of tungsten and molybdenum, and boron. In the conductive layer X, nickel and boron may be alloyed, or at least one of tungsten and molybdenum may be alloyed with boron. Further, in the conductive layer X, in addition to tungsten, molybdenum, and boron, chromium and cyborgium may be used.

Further, in the conductive particles having a nickel conductive layer not containing boron, the nickel conductive layer containing no boron is relatively soft in the initial stage of compression, and an oxide film on the surfaces of the electrodes and the conductive particles is eliminated at the time of connection between the electrodes The effect becomes smaller, and the effect of lowering the connection resistance tends to be smaller. Further, the conductive layer may contain phosphorus other than boron. In the conductive particles having a conductive layer containing nickel and phosphorus, the effect of excluding the oxide film on the surfaces of the electrodes and the conductive particles is reduced, and the effect of lowering the connection resistance tends to become smaller.

On the other hand, in order to further attain the effect of lowering the connection resistance or to increase the thickness of the conductive layer containing no boron or the thickness of the conductive layer containing nickel and phosphorus , The member to be connected or the substrate tends to be easily scratched by the conductive particles. As a result, the reliability of conduction between the electrodes in the connection structure tends to be lowered.

On the other hand, when the conductive layer X contains boron, since the conductive layer has appropriate hardness, damage to the electrode is less likely to occur, and thus the connection resistance between the electrodes is further reduced.

When the conductive layer X is a nickel-tungsten / molybdenum-boron conductive layer, the nickel-tungsten / molybdenum-boron conductive layer has appropriate hardness. Therefore, when the conductive particles are compressed to connect the electrodes, An appropriate indentation can be formed. The indentations formed on the electrodes are concave portions of the electrodes generated by pressing the electrodes with the conductive particles.

The content of boron in the entire 100 wt% of the conductive layer X is preferably 0.01 wt% or more, more preferably 0.05 wt% or more, further preferably 0.1 wt% or more, preferably 5 wt% By weight, preferably not more than 4% by weight, more preferably not more than 3% by weight, particularly preferably not more than 2.5% by weight, most preferably not more than 2% by weight. If the boron content is lower than the lower limit described above, the conductive layer X becomes harder, and the oxide film on the surface of the electrode and the conductive particles can be removed more effectively, and the connection resistance between the electrodes is further lowered. If the content of boron is not more than the upper limit, the content of nickel, tungsten, molybdenum and the like becomes relatively large, so that the connection resistance between the electrodes is further lowered.

Further, since the conductive layer X contains boron, the conductive layer is considerably hardened, so that even if an impact is applied to the connection structure in which the electrodes are connected by the conductive particles, the conduction defect is less likely to occur. That is, the impact resistance of the connection structure can be increased.

The surface of the conductive layer including nickel and boron has a high magnetic property and tends to be easily connected to adjacent electrodes in the transverse direction due to the influence of the conductive particles agglomerated by magnetism when the electrodes are electrically connected to each other . Since the conductive layer X contains at least one of nickel, tungsten, and molybdenum and boron, the magnetic properties of the surface of the conductive layer X are significantly lowered. Therefore, aggregation of a plurality of conductive particles can be suppressed. Therefore, when the electrodes are electrically connected to each other, it is possible to suppress the connection between the adjacent electrodes in the transverse direction due to the agglomerated conductive particles. That is, it is possible to further prevent a short circuit between adjacent electrodes.

It is preferable that the conductive layer X does not contain phosphorus or that the conductive layer X includes phosphorus and the content of phosphorus in the entire 100 wt% of the conductive layer X is less than 0.5 wt%. The content of phosphorus in the entire 100 wt% of the conductive layer X is more preferably 0.3 wt% or less, and further preferably 0.1 wt% or less. It is particularly preferable that the conductive layer X does not contain phosphorus.

Various methods of measuring the respective contents of nickel, tungsten, molybdenum, boron and phosphorus in the conductive layer X can be used, and are not particularly limited. As the above measuring method, there can be mentioned an absorption analysis method or a spectrum analysis method. In the absorption analysis method, a frame absorption spectrophotometer and an electric heating spectrophotometer can be used. Examples of the spectrum analysis include plasma emission analysis and plasma ion mass spectrometry.

When measuring the content of nickel, tungsten, molybdenum, boron and phosphorus in the conductive layer X, it is preferable to use an ICP emission spectrometer. Commercially available products of the ICP emission spectrometer include ICP emission spectrometers manufactured by Horiba.

An FE-TEM device is preferably used when measuring the respective contents of nickel, tungsten, molybdenum, boron and phosphorus in the thickness direction of the conductive layer X. As a commercial product of the FE-TEM device, JEM-2010 manufactured by Nihon Denshi Co., Ltd. and the like can be mentioned.

The metal for forming the other conductive layer (second conductive layer) is not particularly limited. Examples of the metal include gold, silver, copper, palladium, platinum, zinc, iron, tin, lead, aluminum, cobalt, indium, nickel, chromium, titanium, antimony, bismuth, thallium, germanium, cadmium, , Molybdenum, alloys thereof, and the like. Examples of the metal include indium tin oxide (ITO) and solder. Among them, an alloy containing tin, nickel, palladium, copper or gold is preferable, and nickel or palladium is more preferable because the connection resistance between the electrodes is further lowered. The metal constituting the conductive layer preferably includes nickel.

The method for forming the conductive layer (the other conductive layer and the conductive layer X) on the surface of the base particles is not particularly limited. As a method for forming the conductive layer, for example, a method of electroless plating, a method of electroplating, a method of physical vapor deposition, and a method of forming a paste containing metal powder or metal powder and a binder, And a method of coating on the surface. Among them, the electroless plating method is preferable because the formation of the conductive layer is simple. Examples of the physical deposition method include vacuum deposition, ion plating and ion sputtering.

The particle diameter of the conductive particles is preferably 0.11 占 퐉 or more, more preferably 0.5 占 퐉 or more, further preferably 0.51 占 퐉 or more, particularly preferably 1 占 퐉 or more, preferably 100 占 퐉 or less, more preferably 20 占Mu m or less, more preferably 5.6 mu m or less, particularly preferably 3.6 mu m or less. When the particle diameter of the conductive particles is not less than the lower limit and not more than the upper limit, the contact area between the conductive particles and the electrode becomes sufficiently large when the electrodes are connected using the conductive particles, and when the conductive particles are formed, . Further, the distance between the electrodes connected via the conductive particles is not excessively large, and the conductive layer becomes difficult to peel off from the surface of the base particles.

The particle diameter of the conductive particles indicates the diameter when the conductive particles are spherical, and the maximum diameter when the conductive particles are not spherical.

The thickness of the conductive layer X is preferably 0.005 占 퐉 or more, more preferably 0.01 占 퐉 or more, further preferably 0.05 占 퐉 or more, preferably 1 占 퐉 or less, more preferably 0.3 占 퐉 or less. When the thickness of the conductive layer X is not less than the lower limit and not more than the upper limit, sufficient conductivity is obtained, the conductive particles are not too hard, and the conductive particles are sufficiently deformed at the time of connection between the electrodes.

In the case where the conductive layer is a laminate structure of two or more layers, the thickness of the conductive layer X is preferably 0.001 m or more, more preferably 0.01 m or more, still more preferably 0.05 m or more, preferably 0.5 m or less Is not more than 0.3 mu m, and more preferably not more than 0.1 mu m. If the thickness of the conductive layer X is not less than the lower limit and not more than the upper limit, the covering by the conductive layer X can be made uniform, and the connection resistance between the electrodes becomes sufficiently low.

When the conductive layer is a laminate structure of two or more layers, the thickness of the entire conductive layer is preferably 0.001 m or more, more preferably 0.01 m or more, still more preferably 0.05 m or more, particularly preferably 0.1 m or more Is not more than 1 mu m, more preferably not more than 0.5 mu m, still more preferably not more than 0.3 mu m, further preferably not more than 0.1 mu m. When the total thickness of the conductive layer is not less than the lower limit and not more than the upper limit, the covering by the whole conductive layer can be made uniform, and the connection resistance between the electrodes becomes sufficiently low.

The thickness of the conductive layer X is particularly preferably 0.05 mu m or more and 0.3 mu m or less. (More preferably not less than 0.5 占 퐉, more preferably not less than 2 占 퐉) and not more than 5 占 퐉 (more preferably not more than 3 占 퐉), and the thickness of the conductive layer X is 0.05 Mu] m or more and 0.3 [mu] m or less. The thickness of the entire conductive layer is particularly preferably 0.05 mu m or more and 0.3 mu m or less. (More preferably, not less than 0.5 占 퐉, and more preferably not less than 2 占 퐉) and not more than 5 占 퐉 (more preferably not more than 3 占 퐉), and the total thickness of the conductive layer is 0.05 Mu] m or more and 0.3 [mu] m or less. In these cases, the conductive particles can be suitably used depending on applications in which large current flows. In addition, when the conductive particles are compressed to connect the electrodes, it is possible to further suppress damage to the electrodes.

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

Examples of the method for controlling the respective contents of nickel, tungsten, molybdenum and boron in the conductive layer X include a method of controlling the pH of the nickel plating solution when forming the conductive layer X by electroless nickel plating, A method of adjusting the concentration of boron-containing reducing agent when forming the conductive layer X by plating, a method of adjusting the concentration of tungsten in the nickel plating solution, a method of adjusting the concentration of molybdenum in the nickel plating solution and a method of adjusting the concentration of nickel salt in the nickel plating solution And the like.

As a method of making the concentration gradient of nickel, tungsten, molybdenum or boron in the conductive layer X, there is a method of adjusting the compounding amount of the compounding component including nickel, tungsten, molybdenum or boron depending on the formation time of the electroless nickel plating And the like.

As a method of forming by electroless plating, generally a catalytic process and an electroless plating process are performed. An example of a method of forming an alloy plating layer containing nickel, at least one of tungsten and molybdenum, and boron on the surface of resin particles by electroless plating will be described below.

In the catalytic process, a catalyst serving as a starting point for forming a plating layer by electroless plating is formed on the surface of the resin particles.

As a method for forming the catalyst on the surface of the resin particles, for example, resin particles are added to a solution containing palladium chloride and tin chloride, the surface of the resin particles is activated by an acid solution or an alkali solution, And a method in which resin particles are added to a solution containing palladium sulfate and aminopyridine and then the surface of the resin particles is activated by a solution containing a reducing agent to precipitate palladium on the surface of the resin particles And the like. As the reducing agent, a boron-containing reducing agent is preferably used. However, a phosphorus-containing reducing agent such as sodium hypophosphite may be used as the reducing agent.

In the electroless plating step, a nickel plating bath containing nickel salt, at least one of a tungsten-containing compound and a molybdenum-containing compound, and the boron-containing reducing agent is used. By immersing the resin particles in the nickel plating bath, nickel can be deposited on the surface of the resin particles formed on the surface of the catalyst, and a conductive layer containing at least one of nickel, tungsten, and molybdenum and boron can be formed.

Examples of the tungsten-containing compound include tungsten boride and sodium tungstate.

Examples of the molybdenum-containing compound include molybdenum boride and sodium molybdate.

Examples of the boron-containing reducing agent include dimethylamine borane, sodium borohydride, and potassium borohydride.

The conductive particles according to the present invention preferably have projections on the surface. It is preferable that the conductive layer has a projection on the outer surface. In many cases, an oxide film is formed on the surface of an electrode connected by conductive particles. In many cases, an oxide film is formed on the surface of the conductive layer of the conductive particles. By using the conductive particles having projections, conductive particles are disposed between the electrodes and then pressed, whereby the oxide film is effectively removed by the projections. Therefore, the electrode and the conductive particle can be brought into contact more reliably, and the connection resistance between the electrodes can be reduced. Further, when the conductive particles have an insulating material on the surface or when the conductive particles are dispersed in the resin and used as a conductive material, the insulating material or resin between the conductive particles and the electrode can be effectively removed by the protrusions of the conductive particles have. Therefore, the conduction reliability between the electrodes can be improved.

It is preferable that the projections are plural. The protrusions on the outer surface of the conductive layer per one conductive particle are preferably three or more, more preferably five or more. The upper limit of the number of the projections is not particularly limited. The upper limit of the number of the projections can be appropriately selected in consideration of the particle diameter of the conductive particles and the like.

The average height of the plurality of projections is preferably 0.001 m or more, more preferably 0.05 m or more, preferably 0.9 m or less, and more preferably 0.2 m or less. When the average height of the projections is not less than the lower limit and not more than the upper limit, the connection resistance between the electrodes can be effectively lowered.

[Core material]

Since the core material is embedded in the conductive layer, it is easy for the conductive layer to have a plurality of projections on the outer surface. However, in order to form projections on the surfaces of the conductive particles and the conductive layer, the core material may not necessarily be used.

Examples of the method of forming the projections include a method in which a core material is attached to the surface of base particles and then a conductive layer is formed by electroless plating and a method in which a conductive layer is formed on the surface of base particles by electroless plating, A method in which a substance is adhered and a conductive layer is further formed by electroless plating.

Examples of the method for disposing the core material on the surface of the base particles include a method in which a core material is added to a dispersion of the base particles and the core material is accumulated and adhered to the surface of the base particles by Van der Waals force A method in which a core material is added to a container containing base particles and a core material is adhered to the surface of the base particles by a mechanical action by rotating the container or the like. Among them, a method of integrating and adhering the core material on the surface of the base particles in the dispersion is preferable because it is easy to control the amount of the core material to be adhered.

Examples of the material constituting the core material include a conductive material and a non-conductive material. Examples of the conductive material include metals, oxides of metals, conductive nonmetals such as graphite, and conductive polymers. Examples of the conductive polymer include polyacetylene. Examples of the non-conductive material include silica, alumina, barium titanate, and zirconia. Among them, a metal is preferable because the conductivity can be increased and the connection resistance can be further effectively lowered. The core material is preferably a metal particle.

Examples of the metal include metals such as gold, silver, copper, platinum, zinc, iron, lead, tin, aluminum, cobalt, indium, nickel, chromium, titanium, antimony, bismuth, germanium and cadmium, Alloys, tin-copper alloys, tin-silver alloys, tin-lead-silver alloys, and alloys composed of two or more metals such as tungsten carbide. Among them, nickel, copper, silver or gold is preferable. The metal constituting the core material may be the same as or different from the metal constituting the conductive layer. The metal constituting the core material preferably includes a metal constituting the conductive layer. The metal constituting the core material preferably includes nickel. The metal constituting the core material preferably includes nickel.

The shape of the core material is not particularly limited. The shape of the core material is preferably agglomerated. Examples of the core material include a lump of particles, an agglomerated mass agglomerated by a plurality of minute particles, and a lump of an irregular shape.

The average diameter (average particle diameter) of the core material is preferably 0.001 占 퐉 or more, more preferably 0.05 占 퐉 or more, preferably 0.9 占 퐉 or less, and more preferably 0.2 占 퐉 or less. When the average diameter of the core material is not less than the lower limit and not more than the upper limit, the connection resistance between the electrodes can be effectively lowered.

The " average diameter (average particle diameter) " of the core material represents a number average diameter (number average particle diameter). The average diameter of the core material is obtained by observing 50 of any core material with an electron microscope or an optical microscope to calculate an average value.

The inorganic particles may be disposed on the surface of the core material. It is preferable that the number of the inorganic particles disposed on the surface of the core material is plural. An inorganic particle may be attached to the surface of the core material. Composite particles having such an inorganic particle and a core material may be used. The size (average diameter) of the inorganic particles is preferably smaller than the size (average diameter) of the core material, and the inorganic particles are preferably inorganic fine particles.

(MoS hardness of 9 to 9), tungsten carbide (MoS hardness of 9), alumina (Mohs hardness of 9 to 9), zirconia (Moh's hardness of 8 to 9) And diamond (Mohs hardness 10). The inorganic particles are preferably silica, zirconia, alumina, tungsten carbide or diamond, and silica, zirconia, alumina or diamond is also preferable. The Mohs hardness of the inorganic particles is preferably 5 or more, and more preferably 6 or more. The Mohs hardness of the inorganic particles is preferably larger than the Mohs hardness of the conductive layer. The Mohs hardness of the inorganic particles is preferably larger than the Mohs hardness of the second conductive layer. The absolute value of the difference between the Mohs hardness of the inorganic particles and the Mohs hardness of the conductive layer and the difference between the Mohs hardness of the inorganic particles and the Mohs hardness of the second conductive layer is preferably 0.1 or more, 0.2 or more, more preferably 0.5 or more, particularly preferably 1 or more. When the conductive layer is formed of a plurality of layers, the effect of reducing the connection resistance is more effectively exhibited when the inorganic particles are harder than all the metals constituting the plurality of layers.

The average particle diameter of the inorganic particles is preferably 0.0001 占 퐉 or more, more preferably 0.005 占 퐉 or more, preferably 0.5 占 퐉 or less, and more preferably 0.1 占 퐉 or less. When the average particle diameter of the inorganic particles is not less than the lower limit and not more than the upper limit, the connection resistance between the electrodes can be effectively lowered.

The " average particle diameter " of the inorganic particles indicates the number average particle diameter. The average particle diameter of the inorganic particles is obtained by observing 50 arbitrary inorganic particles with an electron microscope or an optical microscope and calculating an average value.

In the case of using the composite particles in which the inorganic particles are disposed on the surface of the core material, the average diameter (average particle diameter) of the composite particles is preferably 0.0012 占 퐉 or more, more preferably 0.0502 占 퐉 or more, Mu m or less, and more preferably 1.2 mu m or less. When the average diameter of the composite particles is not less than the lower limit and not more than the upper limit, the connection resistance between the electrodes can be effectively lowered.

The " mean diameter (average particle diameter) " of the composite particles represents the number average diameter (number average particle diameter). The average diameter of the composite particles is determined by observing 50 arbitrary composite particles with an electron microscope or an optical microscope and calculating an average value.

[Insulating material]

The conductive particles according to the present invention preferably include an insulating material disposed on the surface of the conductive layer. In this case, if the conductive particles are used for connection between the electrodes, a short circuit between the adjacent electrodes can be prevented. Specifically, when a plurality of conductive particles are brought into contact with each other, an insulating material exists between the plurality of electrodes, so that a short circuit can be prevented between the adjacent electrodes in the transverse direction, not between the upper and lower electrodes. Further, at the time of connection between the electrodes, the conductive particles of the conductive particles can be easily excluded from the insulating material between the electrodes by pressing the conductive particles with the two electrodes. Since the conductive particles have a plurality of protrusions on the outer surface of the conductive layer, the insulating material between the conductive layer of the conductive particles and the electrode can be easily removed.

It is preferable that the insulating material is an insulating particle since the insulating material can be more easily removed at the time of pressing between the electrodes.

Specific examples of the insulating resin as a material of the insulating material include polyolefins, (meth) acrylate polymers, (meth) acrylate copolymers, block polymers, crosslinked products of thermoplastic resins, thermoplastic resins, thermosetting resins and water- have.

Examples of the polyolefins include polyethylene, ethylene-vinyl acetate copolymer, and ethylene-acrylic acid ester copolymer. Examples of the (meth) acrylate polymer include polymethyl (meth) acrylate, polyethyl (meth) acrylate, and polybutyl (meth) acrylate. Examples of the block polymer include polystyrene, styrene-acrylic acid ester copolymer, SB-type styrene-butadiene block copolymer, SBS-type styrene-butadiene block copolymer, and hydrogenated products thereof. Examples of the thermoplastic resin include vinyl polymers and vinyl copolymers. Examples of the thermosetting resin include an epoxy resin, a phenol resin, and a melamine resin. Examples of the water-soluble resin include polyvinyl alcohol, polyacrylic acid, polyacrylamide, polyvinylpyrrolidone, polyethylene oxide, methylcellulose and the like. Among them, a water-soluble resin is preferable, and polyvinyl alcohol is more preferable.

Methods for disposing the insulating material on the surface of the conductive layer include a chemical method and a physical or mechanical method. Examples of the chemical method include an interfacial polymerization method, a suspension polymerization method in the presence of particles, and an emulsion polymerization method. Examples of physical or mechanical methods include spray drying, hybridization, electrostatic deposition, spraying, dipping, and vacuum deposition. Among them, a method of disposing the insulating material on the surface of the conductive layer through chemical bonding is preferable in that the insulating material is difficult to desorb.

The average diameter (average particle diameter) of the insulating material can be appropriately selected depending on the particle diameter of the conductive particles and the use of the conductive particles. The average diameter (average particle diameter) of the insulating material is preferably 0.005 占 퐉 or more, more preferably 0.01 占 퐉 or more, preferably 1 占 퐉 or less, and more preferably 0.5 占 퐉 or less. When the average diameter of the insulating material is not less than the lower limit described above, the conductive layers in the plurality of conductive particles are less likely to contact each other when the conductive particles are dispersed in the binder resin. When the average diameter of the insulating particles is less than the upper limit, it is not necessary to excessively increase the pressure in order to exclude the insulating material between the electrodes and the conductive particles at the time of connection between the electrodes, and it is unnecessary to heat the electrodes at a high temperature.

The " average diameter (average particle diameter) " of the insulating material indicates a number average diameter (number average particle diameter). The average diameter of the insulating material is obtained by using a particle size distribution measuring device or the like.

(Conductive material)

The conductive material according to the present invention includes the above-described conductive particles and a binder resin. The conductive particles are preferably dispersed in the binder resin and used as a conductive material. The conductive material is preferably an anisotropic conductive material.

The binder resin is not particularly limited. As the binder resin, a known insulating resin is used.

Examples of the binder resin include a vinyl resin, a thermoplastic resin, a curable resin, a thermoplastic block copolymer and an elastomer. The binder resin may be used alone or in combination of two or more.

Examples of the vinyl resin include vinyl acetate resin, acrylic resin and styrene resin. Examples of the thermoplastic resin include a polyolefin resin, an ethylene-vinyl acetate copolymer, and a polyamide resin. Examples of the curable resin include an epoxy resin, a urethane resin, a polyimide resin and an unsaturated polyester resin. The curable resin may be a room temperature curable resin, a thermosetting resin, a photo-curable resin or a moisture-curable resin. The curable resin may be used in combination with a curing agent. Examples of the thermoplastic block copolymer include styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, hydrogenation product of styrene-butadiene-styrene block copolymer, and styrene-isoprene- Hydrogenated products, and the like. Examples of the elastomer include styrene-butadiene copolymer rubber, and acrylonitrile-styrene block copolymer rubber.

The conductive material may contain, in addition to the conductive particles and the binder resin, a filler, an extender, a softener, a plasticizer, a polymerization catalyst, a curing catalyst, a colorant, an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, And the like.

As the method of dispersing the conductive particles in the binder resin, conventionally known dispersion methods can be used and there is no particular limitation. Examples of the method for dispersing the conductive particles in the binder resin include a method in which the conductive particles are added to the binder resin and then kneaded and dispersed with a planetary mixer or the like; a method in which the conductive particles are homogeneously dispersed in water or an organic solvent A method in which the binder resin is uniformly dispersed in a binder resin and then added to the binder resin and kneaded and dispersed by a planetary mixer or the like; and a method in which the binder resin is diluted with water or an organic solvent, Followed by kneading with a planetary mixer or the like and dispersing the mixture.

The conductive material according to the present invention can be used as a conductive paste and a conductive film. When the conductive material according to the present invention is a conductive film, a film not containing conductive particles may be laminated on the conductive film containing conductive particles. The conductive paste is preferably an anisotropic conductive paste. The conductive film is preferably an anisotropic conductive film.

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

The content of the conductive particles in 100 wt% of the conductive material is preferably 0.01 wt% or more, more preferably 0.1 wt% or more, preferably 40 wt% or less, more preferably 20 wt% or less, Is not more than 10% by weight. When the content of the conductive particles is not less than the lower limit and not more than the upper limit, the reliability of the conduction between the electrodes is further increased.

(Connection structure)

The connection structure can be obtained by connecting the members to be connected using the conductive particles of the present invention or by using the conductive particles and the conductive material containing the binder resin.

Wherein the connection structure includes a first connection target member, a second connection target member, and a connection portion connecting the first and second connection target members, wherein the connection portion is formed by the conductive particles of the present invention, or And is preferably a connection structure formed by a conductive material (anisotropic conductive material or the like) including the conductive particles and a binder resin. In the case where conductive particles are used, the connection itself is a conductive particle. That is, the first and second connection target members are connected by the conductive particles.

4 is a front sectional view schematically showing a connection structure using conductive particles according to a first embodiment of the present invention.

The connection structure 51 shown in Fig. 4 includes a connection member 54 connecting the first connection object member 52, the second connection object member 53 and the first and second connection object members 52 and 53 . The connecting portion 54 is formed by curing a conductive material containing the conductive particles 1. [ In Fig. 4, the conductive particles 1 are schematically shown for convenience of illustration.

The first connection target member 52 has a plurality of electrodes 52b on its upper surface 52a (surface). The second connection target member 53 has a plurality of electrodes 53b on the lower surface 53a (surface). And the electrode 52b and the electrode 53b are electrically connected to each other by one or a plurality of 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 connection structure is not particularly limited. As an example of a manufacturing method of the connection structure, there is a method of arranging the conductive material between the first connection target member and the second connection target member to obtain a laminate, and then heating and pressing the laminate.

The pressure of the pressurization is about 9.8 x 10 ⁴ to 4.9 x 10 ⁶ Pa. The temperature of the heating is about 120 to 220 占 폚.

Specifically, examples of the member to be connected include electronic parts such as semiconductor chips, condensers and diodes, and electronic parts such as printed boards, flexible printed boards and circuit boards such as glass boards. The connection target member is preferably an electronic component. The conductive particles are preferably used for electrical connection of electrodes in an electronic component.

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

Hereinafter, the present invention will be described in detail with reference to examples and comparative examples. The present invention is not limited to the following examples.

(Example 1)

Divinylbenzene copolymer resin particles (Micropearl SP-203, manufactured by Sekisui Chemical Co., Ltd.) having a particle size of 3.0 占 퐉 were prepared.

10 parts by weight of the resin particles were dispersed by using an ultrasonic dispersing machine in 100 parts by weight of an alkali solution containing 5% by weight of a palladium catalyst solution, and then the solution was filtered to take out the resin particles. Subsequently, the resin particles were added to 100 parts by weight of a 1 wt% solution of dimethylamine borane to activate the surface of the resin particles. The surface-activated resin particles were sufficiently washed with water and then added to 500 parts by weight of distilled water, followed by dispersion to obtain a suspension.

Further, a nickel plating solution (pH 8.5) containing 0.23 mol / L of nickel sulfate, 0.92 mol / L of dimethylamine borane, 0.5 mol / L of sodium citrate and 0.01 mol / L of sodium tungstate was prepared. While stirring the obtained suspension at 60 占 폚, the nickel plating solution was gradually dropped into the suspension, and an electroless plating electrical process was performed.

Subsequently, a plating solution (pH 11.0) containing 0.92 mol / L of dimethylamine borane and 0.01 mol / L of sodium tungstate was slowly added dropwise to carry out a later electroless plating step. Thereafter, the suspension was filtered to take out the particles, washed with water and dried to obtain conductive particles having a nickel-tungsten-boron conductive layer (thickness: 0.1 mu m) disposed on the surface of the resin particles.

(Example 2)

In the same manner as in Example 1 except that the concentration of sodium tungstate was changed to 0.12 mol / L in the electrical process and the latter process, the conductivity (in which the nickel-tungsten-boron conductive layer Particles were obtained.

(Example 3)

In the same manner as in Example 1 except that the concentration of sodium tungstate was changed to 0.23 mol / L in the electric process and the latter process, the conductivity (in which the nickel-tungsten-boron conductive layer Particles were obtained.

(Example 4)

In the same manner as in Example 1 except that the concentration of sodium tungstate was changed to 0.35 mol / L in the electric process and the latter process, the conductivity (in which the nickel-tungsten-boron conductive layer Particles were obtained.

(Example 5)

In the same manner as in Example 1 except that the concentration of dimethylamine borane was changed to 2.76 mol / L and the concentration of sodium tungstate was changed to 0.35 mol / L in the electric and late processes, nickel -Tungsten-boron conductive layer (having a thickness of 0.1 mu m).

(Example 6)

(1) palladium deposition process

And a divinylbenzene resin particle (Micropearl SP-205, manufactured by Sekisui Chemical Co., Ltd.) having a particle size of 5.0 mu m was prepared. The resin particles were etched and washed with water. Next, resin particles were added to 100 mL of a palladium catalyzed solution containing 8 wt% of palladium catalyst and stirred. Thereafter, it was filtered and washed. Resin particles were added to a 0.5 wt% dimethylamine borane solution having a pH of 6 to obtain resin particles having palladium attached thereto.

(2) Core material deposition process

The resin particles having palladium attached thereto were stirred and dispersed in 300 mL of ion-exchanged water for 3 minutes to obtain a dispersion. Subsequently, 1 g of metallic nickel particle slurry (average particle diameter 100 nm) was added to the above dispersion for 3 minutes to obtain resin particles having a core material attached thereto.

(3) Electroless nickel plating process

In the same manner as in Example 1, conductive particles having a nickel-tungsten-boron conductive layer (thickness of 0.1 mu m) disposed on the surface of the resin particles were obtained.

(Example 7)

In the same manner as in Example 6 except that the concentration of sodium tungstate was changed to 0.35 mol / L in the electrical process and the latter process, conductivity (in which the thickness of 0.1 탆 of nickel-tungsten-boron conductive layer) Particles were obtained.

(Example 8)

(1) Preparation of insulating particles

100 mmol of methyl methacrylate and 100 mmol of N, N, N-trimethyl-N-2-methacryloxypropyltrimethoxysilane were added to a 1000-mL separable flask equipped with a four-necked separable cover, stirrer, three-way cock, A monomer composition comprising 1 mmol of roile oxyethylammonium chloride and 1 mmol of 2,2'-azobis (2-amidinopropane) dihydrochloride was weighed into ion-exchange water so that the solids content would be 5% by weight ), The mixture was stirred at 200 rpm, and polymerization was carried out at 70 캜 for 24 hours in a nitrogen atmosphere. After completion of the reaction, the resultant was lyophilized to obtain insulating particles having an ammonium group on the surface and an average particle diameter of 220 nm and a CV value of 10%.

The insulating particles were dispersed in ion-exchanged water under ultrasonic irradiation to obtain a 10 wt% aqueous dispersion of insulating particles.

10 g of the conductive particles obtained in Example 6 were dispersed in 500 mL of ion-exchanged water, 4 g of an aqueous dispersion of insulating particles was added, and the mixture was stirred at room temperature for 6 hours. The mixture was filtered with a 3 탆 mesh filter, then washed with methanol, and dried to obtain conductive particles having insulating particles adhered thereto.

As a result of observation by a scanning electron microscope (SEM), only one coating layer composed of insulating particles was formed on the surface of the conductive particles. The coated area of the insulating particles (i.e., the projected area of the particle diameter of the insulating particles) from the center of the conductive particles to the area of 2.5 占 퐉 was calculated by image analysis, and the coating rate was 30%.

(Example 9)

In the same manner as in Example 1 except that the concentration of sodium tungstate was changed to 0.46 mol / L in the electrical process and the latter process, conductivity (in which the nickel-tungsten-boron conductive layer Particles were obtained.

(Example 10)

A nickel-tungsten-boron conductive layer (thickness of about 0.1 mu m) was disposed on the surface of the resin particles in the same manner as in Example 3 except that the concentration of dimethylamine borane was changed to 4.60 mol / L in the electric and late processes Conductive particles were obtained.

(Comparative Example 1)

In the electric process, nickel, tungsten and phosphorus were contained on the surface of the resin particles in the same manner as in Example 1, except that 0.92 mol / L of dimethylamine borane in the nickel plating solution was changed to 0.5 mol / L of sodium hypophosphite (Thickness: 0.1 mu m) was disposed on the surface of the conductive particles.

(Comparative Example 2)

In the same manner as in Example 1 except that 0.01 mol / L of sodium tungstate in the nickel plating solution was not used in the electrical process and the later process, a conductive layer containing nickel and boron (having a thickness of 0.1 mu m ) Was disposed on the conductive particles.

(Example 11)

Divinylbenzene copolymer resin particles (Micropearl SP-203, manufactured by Sekisui Chemical Co., Ltd.) having a particle size of 3.0 占 퐉 were prepared.

10 parts by weight of the resin particles were dispersed by using an ultrasonic dispersing machine in 100 parts by weight of an alkali solution containing 5% by weight of a palladium catalyst solution, and then the solution was filtered to take out the resin particles. Subsequently, the resin particles were added to 100 parts by weight of a 1 wt% solution of dimethylamine borane to activate the surface of the resin particles. The surface-activated resin particles were thoroughly washed with water and then added to 500 parts by weight of distilled water to disperse the suspension to obtain a suspension.

A nickel plating solution (pH 8.5) containing 0.23 mol / L of nickel sulfate, 0.92 mol / L of dimethylamine borane, 0.5 mol / L of sodium citrate and 0.01 mol / L of sodium molybdate was prepared.

While stirring the obtained suspension at 60 占 폚, the nickel plating solution was gradually dropped into the suspension, and an electroless plating electrical process was performed.

Subsequently, a plating solution (pH 11.0) containing 0.92 mol / L of dimethylamine borane and 0.01 mol / L of sodium molybdate was slowly added dropwise, and a later electroless plating step was carried out. Thereafter, the suspension was filtered to take out the particles, washed with water and dried to obtain conductive particles having a nickel-molybdenum-boron conductive layer (thickness: 0.1 mu m) disposed on the surface of the resin particles.

(Example 12)

In the same manner as in Example 11 except that the concentration of sodium molybdate was changed to 0.12 mol / L in the electric process and the latter process, a conductive (nickel-molybdenum-boron) Particles were obtained.

(Example 13)

In the same manner as in Example 11 except that the sodium molybdate concentration was changed to 0.23 mol / L in the electric and late processes, the conductive particles (0.1 m in thickness) in which the nickel-molybdenum-boron conductive layer Particles were obtained.

(Example 14)

In the same manner as in Example 11 except that the concentration of sodium molybdate was changed to 0.35 mol / L in the electrical process and the latter process, the conductivity (in which the nickel-molybdenum-boron conductive layer Particles were obtained.

(Example 15)

In the same manner as in Example 11 except that the concentration of dimethylamine borane was changed to 2.76 mol / L and the concentration of sodium molybdate was changed to 0.35 mol / L in the electric and late processes, nickel -Molybdenum-boron conductive layer (having a thickness of 0.1 mu m) was disposed.

(Example 16)

(1) palladium deposition process

And a divinylbenzene resin particle (Micropearl SP-205, manufactured by Sekisui Chemical Co., Ltd.) having a particle size of 5.0 mu m was prepared. The resin particles were etched and washed with water. Next, resin particles were added to 100 mL of a palladium catalyzed solution containing 8 wt% of palladium catalyst and stirred. Thereafter, it was filtered and washed. Resin particles were added to a 0.5 wt% dimethylamine borane solution having a pH of 6 to obtain resin particles having palladium attached thereto.

(2) Core material deposition process

The resin particles having palladium attached thereto were stirred and dispersed in 300 mL of ion-exchanged water for 3 minutes to obtain a dispersion. Next, 1 g of a metallic nickel particle slurry (average particle diameter 100 nm) was added to the above dispersion for 3 minutes to obtain a resin particle having a core material attached thereto.

(3) Electroless nickel plating process

Conductive particles in which a nickel-molybdenum-boron conductive layer (thickness: 0.1 mu m) was disposed on the surface of the resin particles were obtained in the same manner as in Example 11.

(Example 17)

In the same manner as in Example 16 except that the concentration of sodium molybdate was changed to 0.35 mol / L in the electrical process and the latter process, the conductivity (in which the nickel-molybdenum-boron conductive layer Particles were obtained.

(Example 18)

(1) Preparation of insulating particles

100 mmol of methyl methacrylate and 100 mmol of N, N, N-trimethyl-N-2-methacryloxypropyltrimethoxysilane were added to a 1000-mL separable flask equipped with a four-necked separable cover, stirrer, three- A monomer composition comprising 1 mmol of monooxyethylammonium chloride and 1 mmol of 2,2'-azobis (2-amidinopropane) dihydrochloride was weighed into ion-exchange water so that the solid content was 5% by weight, Thereafter, the mixture was stirred at 200 rpm, and polymerization was carried out at 70 캜 for 24 hours in a nitrogen atmosphere. After completion of the reaction, the resultant was lyophilized to obtain insulating particles having an ammonium group on the surface and an average particle diameter of 220 nm and a CV value of 10%.

The insulating particles were dispersed in ion-exchanged water under ultrasonic irradiation to obtain a 10 wt% aqueous dispersion of insulating particles.

10 g of the conductive particles obtained in Example 16 was dispersed in 500 mL of ion-exchanged water, 4 g of an aqueous dispersion of insulating particles was added, and the mixture was stirred at room temperature for 6 hours. The mixture was filtered with a 3 탆 mesh filter, then washed with methanol, and dried to obtain conductive particles having insulating particles adhered thereto.

As a result of observation by a scanning electron microscope (SEM), only one coating layer composed of insulating particles was formed on the surface of the conductive particles. The coated area of the insulating particles (i.e., the projected area of the particle diameter of the insulating particles) from the center of the conductive particles to the area of 2.5 占 퐉 was calculated by image analysis, and the coating rate was 30%.

(Example 19)

In the same manner as in Example 11, except that the concentration of sodium molybdate was changed to 0.46 mol / L in the electric and late processes, the conductive particles (0.1 mu m in thickness) in which nickel-molybdenum- Particles were obtained.

(Example 20)

A nickel-molybdenum-boron conductive layer (thickness of about 0.1 mu m) was disposed on the surface of the resin particles in the same manner as in Example 13, except that the concentration of dimethylamine borane was changed to 4.60 mol / L in the electric and late processes Conductive particles were obtained.

(Comparative Example 3)

A conductive layer containing nickel, molybdenum and phosphorus (having a thickness of 10 nm) was formed on the surface of the resin particle in the same manner as in Example 11 except that 0.92 mol / L of dimethylamine borane in the nickel plating solution was changed to 0.5 mol / L of sodium hypophosphite 0.1 mu m) was disposed on the conductive particles.

(Example 21)

A nickel-tungsten-molybdenum-boron conductive layer (thickness of about 0.1 mu m) was disposed on the surface of the resin particles in the same manner as in Example 6, except that 0.01 mol / L of sodium molybdate was added in the electrical process and the later process Conductive particles were obtained.

(Comparative Example 4)

A nickel-tungsten-molybdenum-boron conductive layer (thickness of about 0.1 mu m) was disposed on the surface of the resin particles in the same manner as in Comparative Example 1, except that 0.01 mol / L of sodium molybdate was added in the electrical process and the later process Conductive particles were obtained.

(evaluation)

(1) Content of nickel, boron, tungsten, and molybdenum in 100 wt% of the entire conductive layer

5 g of conductive particles was added to a mixture of 5 mL of 60% nitric acid and 10 mL of 37% hydrochloric acid to completely dissolve the conductive layer to obtain a solution. Using the obtained solution, the contents of nickel, boron, tungsten and molybdenum were analyzed by an ICP-MS analyzer (manufactured by Hitachi, Ltd.). In addition, the conductive layer in the conductive particles of the examples did not contain phosphorus.

(2) the total content of tungsten and molybdenum in the thickness direction of the conductive layer

And the distribution of the content of each component in the thickness direction of the conductive layer was measured. The respective contents of nickel, boron, tungsten and molybdenum were evaluated in a portion of the conductive layer having a thickness of 5 nm inward from the outer surface of the conductive layer in the thickness direction.

The content distribution of each component in the thickness direction of the conductive layer (the content of each component in the conductive layer portion having a thickness of 5 nm inward from the outer surface of the conductive layer in the thickness direction) was evaluated as follows Respectively.

Using the focused ion beam, thin film segments of the obtained conductive particles were produced. The respective contents of nickel, boron, tungsten, and molybdenum in the conductive layer were measured by an energy dispersive X-ray analyzer (EDS) using a transmission electron microscope FE-TEM ("JEM-2010 FEF" Were measured.

(3) Eluted nickel ion concentration

10 parts by weight of a plurality of conductive particles were immersed in 100 parts by weight of 5 wt% citric acid aqueous solution at 25 캜 for 1 minute. The concentration of nickel ions eluted into the liquid after immersion was measured using an ICP emission spectrometer ("Ultima 2" manufactured by Horiba, Ltd.). And the eluted nickel ion concentration (ppm / cm 2) per unit surface area of the conductive particles was determined.

(4) Plating condition

The plating state of the obtained 50 conductive particles was observed by a scanning electron microscope. And the presence or absence of plating unevenness such as plating cracking or plating peeling was observed. &Quot; Good " when no plating unevenness was observed, and " Bad " when there were five or more conductive particles whose plating unevenness was confirmed.

(5) Coagulation state

10 parts by weight of a bisphenol A type epoxy resin ("Epikote 1009" manufactured by Mitsubishi Chemical Corporation), 40 parts by weight of an acrylic rubber (weight average molecular weight: about 800,000), 200 parts by weight of methyl ethyl ketone, , And 2 parts by weight of a silane coupling agent (" SH6040 ", manufactured by Toray Dow Corning Silicone Co., Ltd.) were mixed and dispersed to prepare a conductive particle having a content of 3 wt% An anisotropic conductive material was obtained.

The obtained anisotropic conductive material was stored at 25 DEG C for 72 hours. After storage, it was evaluated whether or not the agglomerated conductive particles in the anisotropic conductive material were precipitated. &Quot; Good " when the agglomerated conductive particles were not precipitated, and " Bad " when the agglomerated conductive particles were precipitated.

(6) Initial connection resistance

Preparation of the connection structure:

10 parts by weight of a bisphenol A type epoxy resin ("Epikote 1009" manufactured by Mitsubishi Chemical Corporation), 40 parts by weight of an acrylic rubber (weight average molecular weight: about 800,000), 200 parts by weight of methyl ethyl ketone, , And 2 parts by weight of a silane coupling agent (" SH6040 ", manufactured by Toray Dow Corning Silicone Co., Ltd.) were mixed and dispersed to prepare a conductive particle having a content of 3 wt% To obtain a resin composition.

The obtained resin composition was applied to a PET (polyethylene terephthalate) film having a thickness of 50 占 퐉 on one side of which had been subjected to release treatment and dried for 5 minutes by hot air at 70 占 폚 to prepare an anisotropic conductive film. The thickness of the resulting anisotropic conductive film was 12 占 퐉.

The obtained anisotropic conductive film was cut into a size of 5 mm x 5 mm. The cut anisotropic conductive film was placed on the aluminum electrode side of a glass substrate (width 3 cm, length 3 cm) having an aluminum electrode (height 0.2 μm, L / S = 20 μm / 20 μm) In the middle. Subsequently, a two-layer flexible printed substrate (2 cm wide, 1 cm long) having the same aluminum electrode was positioned and aligned so that the electrodes overlapped with each other. The laminate of the glass substrate and the two-layer flexible printed substrate was subjected to thermocompression bonding under conditions of 10 N, 180 占 폚 and 20 seconds to obtain a connection structure. Further, a two-layer flexible printed substrate having an aluminum electrode directly formed on a polyimide film was used.

Measurement of connection resistance:

The connection resistance between the opposing electrodes of the resulting connection structure was measured by the four-terminal method. The initial connection resistance was determined based on the following criteria.

[Evaluation Criteria of Initial Connection Resistance]

○○: Connection resistance is 2.0Ω or less

○: Connection resistance is more than 2.0Ω and less than 3.0Ω

?: Connection resistance is more than 3.0? 5.0?

×: Connection resistance exceeded 5.0Ω

(7) Connection resistance after high temperature and high humidity test

(6) The connection structure obtained in the evaluation of the initial connection resistance was allowed to stand at 85 캜 and 85% humidity for 100 hours. The connection resistance between the electrodes of the connection structure after being left standing was measured by a division method, and the obtained measured value was regarded as a connection resistance after the high temperature and high humidity test. Also, the connection resistance after the high temperature and high humidity test was judged by the following criteria.

[Evaluation Criteria of Connection Resistance after High Temperature and Humidity Test]

○○: Connection resistance is 2.0Ω or less

○: Connection resistance is more than 2.0Ω and less than 3.0Ω

?: Connection resistance is more than 3.0? 5.0?

×: Connection resistance exceeded 5.0Ω

(8) Impact resistance

The impact resistance was evaluated by confirming continuity by dropping the connection structure obtained in the evaluation of the initial connection resistance (6) at a height of 70 cm. The case where the rising rate of the resistance value from the initial resistance value was 50% or less was judged as " good ", and the case where the rising rate of the resistance value from the initial resistance value was more than 50% was judged as " defective ".

(9) presence or absence of indentation

The electrode provided on the glass substrate was observed on the side of the glass substrate of the connection structure obtained in the production of the connection structure evaluated in the above (6) using a differential interference microscope, and the presence or absence of the indentation of the electrode, And evaluated according to the following criteria. The presence or absence of indentation of the electrode was observed with a differential interference microscope so that the electrode area was 0.02 mm 2, and the number of indentations per 0.02 mm 2 of the electrode was calculated. 10 arbitrary points were observed with a differential interference microscope to calculate an average value of the number of indentations per 0.02 mm 2 of the electrode.

[Criteria for judging presence or absence of indentation]

○○: 25 or more indentations per 0.02 ㎟ of electrode

○: Indentations per electrode 0.02 ㎟ exceed 20 but less than 25

△: Indentation per 0.02 ㎟ of electrode is 5 or more and less than 20

X: Less than five indentations per 0.02 mm2 of electrode

The results are shown in Tables 1 to 3 below. In the following Tables 1 to 3, the 5 nm-thick conductive layer portion shows a 5-nm-thick conductive layer portion inward from the outer surface of the conductive layer in the thickness direction. The eluted nickel ion concentration represents the nickel ion concentration eluted per unit surface area of the conductive particles.

One… Conductive particle
1a ... spin
2… Base particles
3 ... Conductive layer
3a ... spin
4… Core material
5 ... Insulating material
11 ... Conductive particle
11a ... spin
12 ... The second conductive layer
13 ... Conductive layer
13a ... spin
21 ... Conductive particle
22 ... Conductive layer
51 ... Connection structure
52 ... The first connection object member
52a ... Top surface
52b ... electrode
53 ... The second connection object member
53a ... if
53b ... electrode
54 ... Connection

Claims (12)

A base particle and a conductive layer disposed on a surface of the base particle,
Wherein the conductive layer comprises at least one metal component selected from the group consisting of nickel, tungsten, and molybdenum,
Wherein the content of nickel in the entire 100 wt% of the conductive layer is 60 wt%
Wherein the total content of tungsten and molybdenum in the conductive layer portion is 5% by weight or more and 100% by weight in the thickness of 5 nm inward from the outer surface of the conductive layer in the thickness direction. The conductive particle according to claim 1, wherein the total content of tungsten and molybdenum in the conductive layer portion of 5 nm in thickness from the outer surface of the conductive layer toward the inner side in the thickness direction is 10% by weight or more. The method according to claim 1 or 2, wherein at least one of the metal components of nickel, tungsten, and molybdenum is localized in the thickness direction of the conductive layer,
Wherein an outer portion of the conductive layer contains a larger amount of the metal component than an inner portion of the conductive layer. The conductive particle according to any one of claims 1 to 3, wherein the total content of tungsten and molybdenum in the total of 100 wt% of the conductive layer exceeds 5 wt%. The method for producing a conductive particle according to any one of claims 1 to 4, wherein 10 parts by weight of a plurality of conductive particles are immersed in 100 parts by weight of a 5 wt% citric acid aqueous solution at 25 캜 for 1 minute, Conductive particles having an electric conductivity of not more than 100 ppm / cm 2. 6. The semiconductor device according to any one of claims 1 to 5, wherein the conductive layer is formed by electroless nickel plating using a reducing agent,
Wherein the conductive layer does not contain a component derived from the reducing agent, or contains a component derived from the reducing agent, and the content of the component derived from the reducing agent in the entire 100 wt% of the conductive layer is 5 wt% or less. 7. The conductive particle according to any one of claims 1 to 6, wherein the conductive layer comprises boron. The conductive particle according to claim 7, wherein the content of boron in the entire 100 wt% of the conductive layer is 0.05 wt% or more and 4 wt% or less. 9. A method according to any one of claims 1 to 8, wherein the conductive layer does not comprise phosphorus, or the conductive layer comprises phosphorus and the content of phosphorus in the total 100% by weight of the conductive layer is less than 0.5% particle. 10. The conductive particle according to any one of claims 1 to 9, wherein the conductive layer has protrusions on the outer surface. A conductive material comprising the conductive particles according to any one of claims 1 to 10 and a binder resin. A first connecting object member, a second connecting object member, and a connecting portion connecting the first and second connecting object members,
Wherein the connecting portion is formed by the conductive particles according to any one of claims 1 to 10 or formed by a conductive material including the conductive particles and the binder resin.

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