KR20150028224A - Conductive particles with insulating particles, conductive material, and connection structure - Google Patents

Abstract

The present invention provides an insulating particle-attached conductive particle capable of increasing both conduction reliability and insulation reliability when electrodes are connected to each other. The insulating particle-attached conductive particle (1) according to the present invention comprises conductive particles (2) having at least a conductive part (12) on at least a surface and a plurality of first insulating particles (3) disposed on the surface of the conductive particle ) And a plurality of second insulating particles (4) arranged on the surface of the conductive particles (2). The average particle diameter of the second insulating particles (4) is smaller than the average particle diameter of the first insulating particles (3). The covering ratio which is the total area of the portion of the entire surface area of the conductive particles 2 covered with the first insulating particles 3 and the second insulating particles 4 exceeds 50%.

Description

FIELD OF THE INVENTION [0001] The present invention relates to conductive particles, conductive materials, and connection structures for insulating particles,

The present invention relates to, for example, conductive particles with insulating particles which can be used for electrical connection between electrodes. The present invention also relates to a conductive material and a connection structure using the insulating particle-adhering conductive particles.

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

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

As an example of the conductive particles, the following Patent Document 1 discloses an insulating particle-adhering conductive particle comprising particles having a conductive metal surface and insulating particles covering the surface of the particles having the conductive metal surface . Patent Document 1 discloses that two or more kinds of insulating particles having different particle diameters are used in combination to introduce small insulating particles into a gap covered by large insulating particles to improve coating density.

Japanese Patent Laid-Open No. 2005-44773

In the insulating particle-attached conductive particle described in Patent Document 1, since the conductive metal surface is covered with the insulating particles, it is possible to suppress the electrical connection between the adjacent electrodes in the transverse direction which should not be connected after the upper and lower conductive connections . That is, the insulation reliability in the conductive connection-connected structure can be improved. In addition, by using two or more kinds of insulating particles having different particle diameters in combination and introducing small insulating particles into the gap covered by the large insulating particles, the coating density becomes high, and as a result, insulation reliability can be improved. However, in Patent Document 1, it is preferable to set the covering ratio of the insulating particles to 5 to 50%, that is, the area of the portion covered by the insulating particles occupying the entire surface area of the metal surface particles is 5 to 50% Is only described.

On the other hand, in recent years, miniaturization of electronic parts is progressing. As a result, in the wiring connected by the conductive particles in the electronic component, the L / S representing the width of the line L in which the wiring is formed and the width of the space S in which no wiring is formed is reduced . In the case where such fine wiring is formed, it is difficult to sufficiently secure the insulation reliability by conducting the conductive connection using the conventional insulating particle-attached conductive particles.

In addition, when conductive connection is performed using the insulating particle-adhered conductive particles, it is required that the insulating particles between the electrode and the conductive particle are sufficiently removed, and high reliability of conduction is also demanded.

In addition, in the conventional insulating particle-attached conductive particles, before the conductive connection, the insulating particles tend to be inadvertently removed from the surface of the conductive particles. For example, when the insulating particle-adhering conductive particles are dispersed in the binder resin, the insulating particles easily detach from the surface of the conductive particles, and the surface of the conductive particles may be exposed. As a result, there is a problem that insulation reliability is lowered.

An object of the present invention is to provide an insulating particle-attached conductive particle which can increase both conduction reliability and insulation reliability when electrodes are connected, and a conductive material and a connection structure using the insulating particle-attached conductive particle.

A limiting object of the present invention is to provide an insulated particle attachment conductive particle which is unlikely to inadvertently detach insulative particles from the surface of the conductive particle even if an impact is applied to the conductive connection before, Structure.

According to a broad aspect of the present invention, there is provided a conductive particle comprising a conductive particle having at least a conductive portion on at least a surface thereof, a plurality of first insulating particles disposed on a surface of the conductive particle, and a plurality of second insulating particles Wherein an average particle diameter of the second insulating particles is smaller than an average particle diameter of the first insulating particles and is covered with the first insulating particles and the second insulating particles which occupy the entire surface area of the conductive particles Wherein the coating area of the conductive particles is in the range of 50% or more.

In a specific aspect of the insulating particle-adhered conductive particles according to the present invention, at least 20% of the total number of the second insulating particles is disposed on the surface of the conductive particles so as to contact the first insulating particles.

In a specific aspect of the insulating particle-adhered conductive particles according to the present invention, at least 50% of the total number of the second insulating particles is disposed on the surface of the conductive particles so as to contact the first insulating particles.

In a specific aspect of the conductive particle with insulating particles according to the present invention, it is preferable that at least 10% of the total number of the second insulating particles is in contact with the conductive particles so as not to contact the first insulating particles, And is disposed on the surface.

In one specific aspect of the conductive particle with insulating particle according to the present invention, the first insulating particle is attached to the surface of the conductive particle through chemical bonding.

In a specific aspect of the insulating particle-adhered conductive particles according to the present invention, the first insulating particles and the second insulating particles are not respectively disposed on the surfaces of the conductive particles by a hybridization method .

In a specific aspect of the conductive particle with insulating particle according to the present invention, the conductive particle has a protrusion on the outer surface of the conductive portion.

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

According to a broad aspect of the present invention, there is provided a liquid crystal display device including a first connection target member having a first electrode on a surface thereof, a second connection target member having a second electrode on a surface thereof, And the connecting portion is formed by the conductive particles having the insulating particle attachment conductive particles or the conductive material including the insulating particle attachment conductive particles and the binder resin, Wherein the electrode and the second electrode are electrically connected by the conductive particles in the insulating particle-attached conductive particle.

The insulating particle-attached conductive particle according to the present invention includes conductive particles having at least a conductive portion on at least a surface thereof, a plurality of first insulating particles disposed on the surface of the conductive particle, and a second insulating material Wherein the first insulating particles and the second insulating particles each having an average particle diameter smaller than an average particle diameter of the first insulating particles and occupying the entire surface area of the conductive particles When the electrodes are connected using the insulating particle-adhering conductive particles according to the present invention, the covering reliability, which is the total area of the covered portions, exceeds 50%, thereby improving the conduction reliability and insulation reliability.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view showing an insulating particle-adhering conductive particle according to a first embodiment of the present invention. Fig.
2 is a cross-sectional view showing an insulating particle-adhering conductive particle according to a second embodiment of the present invention.
3 is a cross-sectional view showing an insulating particle-adhered conductive particle according to a third embodiment of the present invention.
Fig. 4 is a front sectional view schematically showing a connection structure using the insulating particle-adhering conductive particles shown in Fig. 1. Fig.
5 is a schematic diagram for explaining a method of evaluating the coating rate.

Best Mode for Carrying Out the Invention Hereinafter, the present invention will be clarified by explaining specific embodiments and examples of the present invention with reference to the drawings.

(Conductive particles with insulating particles)

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

The insulating particle-attached conductive particle 1 shown in Fig. 1 comprises conductive particles 2, a plurality of first insulating particles 3, and a plurality of second insulating particles 4.

The conductive particles (2) have at least a conductive portion (12) on the surface. The first insulating particles (3) are disposed on the surface of the conductive particles (2). The second insulating particles (4) are disposed on the surface of the conductive particles (2).

The covering ratio which is the total area of the portion of the entire surface area of the conductive particles 2 covered with the first insulating particles 3 and the second insulating particles 4 exceeds 50%.

The plurality of first insulating particles 3 are in contact with the surface of the conductive particles 2 and attached to the surface of the conductive particles 2. [ The plurality of first insulating particles 3 are in contact with the outer surface of the conductive part 12 of the conductive particles 2 and attached to the outer surface of the conductive part 12. The plurality of second insulating particles 4 are in contact with the surface of the conductive particles 2 and attached to the surfaces of the conductive particles 2. [ The plurality of second insulating particles 4 are in contact with the outer surface of the conductive part 12 of the conductive particles 2 and attached to the outer surface of the conductive part 12.

The conductive particles 2 have base particles 11 and conductive portions 12 disposed on the surface of the base particles 11. [ The conductive portion 12 is a conductive layer. The conductive portion 12 covers the surface of the base particle 11. The conductive particles (2) are coated particles in which the surface of the base particles (11) is covered with the conductive parts (12). The conductive particles (2) have conductive portions (12) on their surfaces.

The first insulating particles 3 and the second insulating particles 4 are each formed of a material having an insulating property. The average particle diameter of the second insulating particles (4) is smaller than the average particle diameter of the first insulating particles (3).

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

The insulating particle-adhering conductive particles 21 shown in Fig. 2 include conductive particles 22, a plurality of first insulating particles 3, and a plurality of second insulating particles 4.

The conductive particles 22 have at least a conductive portion 26 on the surface. The first insulating particles (3) are disposed on the surface of the conductive particles (22). The second insulating particles (4) are disposed on the surface of the conductive particles (22).

The covering ratio which is the total area of the portions of the entire surface area of the conductive particles 22 covered with the first insulating particles 3 and the second insulating particles 4 exceeds 50%.

The insulating particle attachment conductive particles 1 and the insulating particle attachment conductive particles 21 differ only in the conductive particles 2 and 22. The conductive particles 22 have base particles 11 and conductive portions 26 disposed on the surface of the base particles 11. [ The conductive particles (22) have a plurality of core materials (27) on the surface of the base particles (11). The conductive portion 26 covers the base particle 11 and the core material 27. [ Since the conductive material 26 covers the core material 27, the conductive particles 22 have a plurality of projections 28 on their surfaces. The surface of the conductive portion 26 is raised by the core material 27 and a plurality of projections 28 are formed.

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

The insulating particle-adhering conductive particles 31 shown in Fig. 3 include conductive particles 32, a plurality of first insulating particles 3, and a plurality of second insulating particles 4.

The conductive particles 32 have conductive portions 36 at least on their surfaces. The first insulating particles (3) are disposed on the surface of the conductive particles (32). The second insulating particles (4) are disposed on the surface of the conductive particles (32).

The covering ratio which is the total area of the portions covered by the first insulating particles 3 and the second insulating particles 4 in the entire surface area of the conductive particles 32 exceeds 50%.

The insulating particle-adhering conductive particles 1 and the insulating particle-adhering conductive particles 31 differ only in the conductive particles 2 and 32. The conductive particles 32 have base particles 11 and a conductive portion 36 disposed on the surface of the base particles 11. The conductive particles 22 have a core material 27, but the conductive particles 32 do not have a core material. The conductive portion 36 has a first portion and a second portion that is thicker than the first portion. The conductive particles 32 have a plurality of projections 37 on the surface. And the portion excluding the plurality of projections 37 is the first portion of the conductive portion 36. [ The plurality of protrusions 37 are the second portions of the conductive portions 36 having a large thickness.

In the insulating particle-adhered conductive particles 1, 21 and 31, the average particle diameter of the second insulating particles 4 is smaller than the average particle diameter of the first insulating particles 3 and the average particle diameter of the conductive particles 2, 22, Which is the total area of the portion covered by the first insulating particles 3 and the second insulating particles 4 in the entire surface area of the first insulating particles 3 exceeds 50%. As a result, when the upper and lower electrodes are electrically connected to each other by using the insulating particle-attached conductive particles (1, 21, 31), the upper and lower electrodes to be connected can be electrically connected to each other, It is possible to suppress the electrical connection between the electrodes. That is, conduction reliability and insulation reliability can be enhanced. In addition, at the time of normal conductive connection, a large force is exerted to affect the desorption of the first and second insulating particles 3 and 4, so that the first and second insulating particles 3 and 4 are desorbed, (2, 22, 32) are brought into contact with the electrode.

It is also possible to effectively prevent the relatively large first insulating particles from being inadvertently released from the surface of the conductive particles due to the impact before the conductive connection. For example, when the insulating particle-adhering conductive particles are dispersed in the binder resin, it is possible to prevent the first insulating particles from desorbing from the surface of the conductive particles. Further, when a plurality of insulating particle-adhering conductive particles are brought into contact with each other, it is difficult for the first insulating particles to detach from the surface of the conductive particles due to impact at the time of contact. In addition, by using the insulating particle-attached conductive particles to electrically connect the upper and lower electrodes to obtain a connection structure, unintentional desorption of the first insulating particles is suppressed even when an impact is applied to the connection structure, It is possible to suppress the connection, and sufficient insulation reliability can be ensured.

From the viewpoint of further enhancing the insulation reliability and the insulation reliability against impact, the covering ratio Z, which is the total area of the portions covered by the first insulating particles and the second insulating particles in the entire surface area of the conductive particles, is preferably Is preferably 51% or more, more preferably 55% or more, still more preferably 60% or more, particularly preferably 70% or more, and most preferably 80% or more. From the viewpoint of further improving insulation reliability and insulation reliability against impact, the covering rate Z is preferably 85% or less. The coating rate Z may be less than 81% or less than 80%.

The covering ratio which is the total area of the first insulating particles and the portion covered by the second insulating particles in the entire surface area of the conductive particles is obtained as follows.

20 insulating particle attachment conductive particles were observed by observation with a scanning electron microscope (SEM), and the coating rate Z (%) of the conductive particles in the insulating particle attachment conductive particles (also referred to as adhesion rate Z (%)) . The covering ratio is the total area (projected area) of the portion covered by the first and second insulating particles in the surface area of the conductive particle.

Specifically, when the insulating particle-attached electroconductive particles are observed from one direction by a scanning electron microscope (SEM), the covering ratio is preferably set to a value within a range of (The hatched portion in FIG. 5 (b)) of the first and second insulating particles in the periphery of the outer peripheral portion of the conductive particles, it means.

The average particle diameter of the second insulating particles is preferably not more than 9/10 of the average particle diameter of the first insulating particles, and more preferably not more than 4/5 of the average particle diameter of the first insulating particles, from the viewpoint of further improving the insulation reliability, More preferably 2/3 or less, and particularly preferably 1/2 or less. The average particle diameter of the second insulating particles is preferably 1/30 or more of the average particle diameter of the first insulating particles, more preferably 1/20 or more, and further preferably 1/10 or more.

The " average particle diameter " of the first and second insulating particles respectively indicate the number average particle diameter. The average particle diameter of the first and second insulating particles is obtained by observing 50 arbitrary conductive particles with an electron microscope or an optical microscope and calculating an average value.

From the viewpoint of further enhancing conduction reliability, it is preferable that at least a part of the second insulating particles are disposed on the surface of the conductive particles so as to be in contact with the first insulating particles. From the viewpoint of further enhancing the conduction reliability, the number of the second insulating particles disposed on the surface of the conductive particles is preferably larger so as to contact the first insulating particles. From the viewpoint of further enhancing the conduction reliability, it is preferable that 10% or more of the total number of the second insulating particles is disposed on the surface of the conductive particles so as to be in contact with the first insulating particles. The number ratio X1 of the second insulating particles disposed on the surface of the conductive particles so as to contact the first insulating particles is more preferably 20% or more, still more preferably 30% or more, still more preferably 40% or more , Even more preferably more than 50%, particularly preferably more than 50%, most preferably more than 80%. When the first insulating particles are in contact with the second insulating particles, the second insulating particles in contact with the first insulating particles tend to desorb as the first insulating particles separate from each other during the conductive connection. As a result, conduction reliability is further enhanced. The total number of the second insulating particles indicates the number of the second insulating particles contained in one conductive particle. The number of the second insulating particles disposed on the surface of the conductive particles so as to come into contact with the first insulating particles includes the number of the second insulating particles in contact with the conductive particles and the number of the second insulating particles in contact with the conductive particles Both of the number of particles are included.

Examples of the method of bringing the second insulating particles into contact with the first insulating particles include a method of surface-treating the first insulating particles so that the second insulating particles are easily adhered, a method of treating the surface of the second insulating particles to facilitate attachment of the first insulating particles And a method in which the second insulating particles are attached to the surface of the first insulating particles and then the first insulating particles having the second insulating particles attached thereto are adhered to the surface of the conductive particles.

It is preferable that at least a part of the second insulating particles are disposed on the surface of the conductive particles so as not to contact the first insulating particles from the viewpoint of further improving insulation reliability and insulation reliability against impact. The number of the second insulating particles disposed on the surface of the conductive particles is preferably larger so as not to contact the first insulating particles from the viewpoint of further improving insulation reliability and insulation reliability against impact. It is preferable that at least 10% of the total number of the second insulating particles is disposed on the surface of the conductive particles so as not to contact the first insulating particles. The number ratio X2 of the second insulating particles disposed on the surface of the conductive particles so as not to contact the first insulating particles is more preferably 20% or more, still more preferably 30% or more, particularly preferably 40% or more , And most preferably 50% or more. The total number of the second insulating particles indicates the number of the second insulating particles contained in one conductive particle. The number of the second insulating particles disposed on the surface of the conductive particles so as not to contact the first insulating particles includes the number of the second insulating particles in contact with the conductive particles and the number of the second insulating particles in contact with the conductive particles, And the number of insulating particles.

It is preferable that 10% or more of the total number of the second insulating particles is disposed on the surface of the conductive particles so as to contact the conductive particles so as not to contact the first insulating particles in order to improve insulation reliability and insulation reliability against impact desirable. The number ratio X3 of the second insulating particles disposed on the surface of the conductive particles so as not to come in contact with the first insulating particles and in contact with the conductive particles is more preferably 10% or more, still more preferably 15% , Particularly preferably not less than 20%, preferably not more than 100%, more preferably not more than 80%, further preferably not more than 60%, particularly preferably not more than 50%. The total number of the second insulating particles indicates the number of the second insulating particles contained in one conductive particle.

Examples of a method of not contacting the first insulating particles with the second insulating particles include a method of surface-treating the first insulating particles so that the second insulating particles are less likely to adhere, a method of forming the second insulating particles on the surface A method of treating the surface of the second insulating particles so that the second insulating particles are more likely to adhere to the conductive particles than the first insulating particles, and the like.

From the viewpoint of further improving the reliability of conduction, insulation reliability and insulation reliability against impact, the average number Y1 of the first insulating particles arranged on the surface of the conductive particles per one conductive particle is preferably 1 More preferably 2 or more, still more preferably 3 or more, particularly preferably 5 or more, most preferably 10 or more, preferably 100 or less, more preferably 50 or less Preferably 20 or less. The average number Y1 may be less than 10. The average number of the first insulating particles disposed on the surface of the conductive particles per one conductive particle is an average of the number of the first insulating particles contained in one conductive particle.

The average number Y2 of the second insulating particles disposed on the surface of the conductive particles per one of the conductive particles is preferably 1 or more from the viewpoint of further improving the reliability of conduction, More preferably 4 or more, more preferably 6 or more, particularly preferably 10 or more, most preferably 20 or more, preferably 1000 or less, more preferably 500 or less Preferably 100 or less. The average number of the second insulating particles disposed on the surface of the conductive particles per one conductive particle is an average of the number of the second insulating particles contained in one conductive particle.

In the conductive particle according to the present invention, the average number Y1 of the first insulating particles disposed on the surface of the conductive particle per one conductive particle, of the conductive particles per surface of the conductive particle, (Average number Y1 / average number Y2) to the average number Y2 of the second insulating particles disposed in the second insulating layer is preferably 0.001 or more, more preferably 0.005 or more, still more preferably 0.05 or more, 1 or less, more preferably 0.5 or less. The ratio (average number Y1 / average number Y2) may exceed 0.5. The number of the first and second insulating particles disposed on the surface of the conductive particles also includes the number of the first and second insulating particles that are not in contact with the conductive particles.

From the viewpoint of further enhancing insulation reliability and insulation reliability against impact, it is preferable that the second insulating particles are attached to the surfaces of the conductive particles through chemical bonding.

From the viewpoint of further suppressing the inadvertent desorption of the first insulating particles from the surface of the conductive particles by the impact, it is preferable that the first insulating particles are attached to the surface of the conductive particles through chemical bonding Do. Further, when the first insulating particles are attached to the surfaces of the conductive particles through chemical bonding, the insulation reliability of the connection structure is further enhanced.

From the viewpoint of improving conduction reliability between the electrodes, it is preferable that the conductive particles have projections on the outer surface of the conductive portion. Generally, in conductive particles having protrusions on the outer surface of the conductive portion, the larger the protrusions, the lower the insulation reliability tends to be. In the insulating particle-attached conductive particle according to the present invention, since the first and second insulating particles are provided, even if the projection is large, the insulation reliability can be sufficiently secured.

From the viewpoint of further improving conduction reliability, insulation reliability and insulation reliability against impact, the degree of crosslinking of the first insulating particles is preferably 5 wt% or more. The degree of crosslinking means the weight ratio of the crosslinking component to the total weight of the polymerizable monomer.

Hereinafter, the details of the conductive particles, the first insulating particles and the second insulating particles in the insulating particle-attached conductive particles will be described.

[Conductive particle]

The conductive particles may have conductive parts at least on their surfaces. The conductive portion is preferably a conductive layer. The conductive particles may be base particles and conductive particles having a conductive layer disposed on the surface of the base particles, and may be metal particles whose entirety is a conductive portion. Among them, conductive particles having a base particle and a conductive portion disposed on the surface of the base particle are preferable from the viewpoint of reducing the cost, increasing the flexibility of the conductive particle, and enhancing the reliability of conduction between the electrodes.

Examples of the base particles include resin particles, inorganic particles other than metal particles, organic-inorganic hybrid particles and metal particles. The base particles may be core shell particles. Among them, the base particles are preferably base particles excluding metal particles, more preferably resin particles, inorganic particles other than metal particles, or organic-inorganic hybrid particles.

The base particles are preferably resin particles formed by a resin. When the electrodes are connected using the insulating particle-attached conductive particles, the insulating particle-attached conductive particles are disposed between the electrodes, and then pressed to compress the insulating particle-attached conductive particles. When the base particles are resin particles, the conductive particles tend to be deformed at the time of pressing, and the contact area between the conductive particles and the electrode becomes large. As a result, the reliability of conduction between the electrodes is further enhanced.

As the resin for forming the resin particles, various organic materials are suitably used. Examples of the resin for forming the resin particles include polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene, and polybutadiene; Acrylic resins such as polymethyl methacrylate and polymethyl acrylate; 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, Various polymerizable monomers having an epoxy resin, an unsaturated polyester resin, a saturated polyester resin, a polysulfone, a polyphenylene oxide, a polyacetal, a polyimide, a polyamideimide, a polyetheretherketone, a polyether sulfone and an ethylenic unsaturated group And polymers obtained by polymerization of one kind or two or more kinds. It is preferable that the resin for forming the resin particles is a polymer obtained by polymerizing at least one polymerizable monomer having an ethylenic unsaturated group.

When the resin particle is obtained by polymerizing a monomer having an ethylenic unsaturated group, examples of the monomer having an ethylenic unsaturated group include a monomer that is incompatible with the monomer and a monomer that 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. Examples of the method include suspension polymerization in the presence of, for example, a radical polymerization initiator, and polymerization by swelling the monomer together with the radical polymerization initiator using non-crosslinked seed particles.

When the base particles are inorganic particles other than metals 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 crosslinked polymer particles, and then firing if necessary, . Examples of the organic-inorganic hybrid particles include organic-inorganic hybrid particles formed of 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 metal for forming the conductive part is not particularly limited. When the conductive particles are metal particles as a whole, the metal for forming the metal particles is not particularly limited. Examples of the metal include gold, silver, palladium, copper, platinum, zinc, iron, tin, lead, aluminum, cobalt, indium, nickel, chromium, titanium, antimony, bismuth, thallium, germanium, cadmium, And the like. Examples of the metal include tin-doped indium oxide (ITO) and solder. Among them, an alloy including tin, nickel, palladium, copper or gold is preferable, and nickel or palladium is preferable because the connection resistance between the electrodes becomes further lower. The melting point of the conductive portion is preferably 300 占 폚 or higher, and more preferably 450 占 폚 or higher. The conductive portion may be a conductive portion instead of solder.

In many cases, hydroxyl groups are present on the surface of the conductive part by oxidation. Generally, on the surface of the conductive part formed by nickel, a hydroxyl group is present due to oxidation. The first insulating particles can be attached to the surface of the conductive portion having the hydroxyl group (the surface of the conductive particle) through chemical bonding. In addition, the second insulating particles may be attached to the surface of the conductive part having the hydroxyl group (the surface of the conductive particle) through chemical bonding.

The conductive layer may be formed by one layer. The conductive layer may be formed by a plurality of layers. That is, the conductive layer may have a laminated structure of two or more layers. When the conductive layer is formed of a plurality of layers, it is preferable that the outermost layer is a gold layer, a nickel layer, a palladium layer, a copper layer, or an alloy layer containing tin and silver, more preferably a gold layer. When the outermost layer is the preferable conductive layer, the connection resistance between the electrodes is further lowered. Further, when the outermost layer is a gold layer, corrosion resistance is further increased.

The method of forming the conductive layer on the surface of the base particles is not particularly limited. Examples of the method of forming the conductive layer include a method of electroless plating, a method of electroplating, a method of physical vapor deposition, and a method of coating a surface of base particles with a paste containing metal powder or metal powder and a binder And the like. 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 average particle diameter of the conductive particles is preferably 0.5 占 퐉 or more, more preferably 1 占 퐉 or more, preferably 500 占 퐉 or less, more preferably 100 占 퐉 or less, further preferably 50 占 퐉 or less, Mu] m or less. When the average particle diameter of the conductive particles is equal to or more than the lower limit and the upper limit, the contact area between the conductive particles and the electrode becomes sufficiently large when the electrodes are connected using the insulating particle-adhering conductive particles, The coagulated conductive particles are hardly formed. Further, the distance between the electrodes connected via the conductive particles does not become excessively large, and the conductive layer becomes difficult to peel off from the surface of the substrate particles.

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

The thickness of the conductive layer is preferably at least 0.005 탆, more preferably at least 0.01 탆, preferably at most 10 탆, more preferably at most 1 탆, further preferably at most 0.3 탆. When the thickness of the conductive layer is not less than the lower limit and not more than the upper limit, sufficient conductivity is obtained and the conductive particles are not excessively hardened and the conductive particles are sufficiently deformed at the time of connection between the electrodes.

In the case where the conductive layer is formed of a plurality of layers, the thickness of the outermost layer of the conductive layer is preferably 0.001 mu m or more, more preferably 0.01 mu m or more , Preferably not more than 0.5 mu m, and more preferably not more than 0.1 mu m. If the thickness of the conductive layer in the outermost layer is not less than the lower limit and not more than the upper limit, the coating of the outermost conductive layer becomes uniform, the corrosion resistance becomes sufficiently high, and the connection resistance between the electrodes becomes sufficiently low. Further, the thinner the thickness of the gold layer when the outermost layer is a gold layer, the lower the cost.

The thickness of the conductive layer can be measured by observing the cross section of the conductive particles or the insulating particle-attached conductive particles using, for example, a transmission electron microscope (TEM).

It is preferable that the conductive particles have protrusions on the outer surface of the conductive portion, and it is preferable that the protrusions have a plurality of protrusions. In many cases, an oxide film is formed on the surface of the electrode connected by the insulating particle-attached conductive particles. In the case of using the insulating particle-adhering conductive particles having protrusions on the surface of the conductive portion, the oxide particles can be effectively removed by projections by disposing the conductive particles with insulating particles between the electrodes and pressing them. As a result, the electrode and the conductive portion come into more reliable contact with each other, and the connection resistance between the electrodes is further lowered. Further, at the time of connection between the electrodes, the protrusions of the conductive particles can effectively remove the insulating particles between the conductive particles and the electrodes. As a result, the reliability of conduction between the electrodes is further enhanced.

Examples of the method for forming protrusions on the surface of the conductive particles 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; A method in which a core material is disposed on the first conductive layer after the layer is formed and then a second conductive layer is formed by electroless plating or the like and a method in which a conductive layer is formed on the surface of the base particle And a method of adding a core material.

As a method for attaching the core material to the surface of the base particles, for example, a method in which a core material is added to a dispersion of the base particles and the core material is accumulated on the surface of the base particles, for example, by Van der Waals force And a method in which a core material is added to a container containing base particles and the core material is adhered to the surface of the base particles by mechanical action by rotation of 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.

The conductive particles may have a first conductive layer on the surface of the base particle and a second conductive layer on the first conductive layer. In this case, the core material may be attached to the surface of the first conductive layer. The core material is preferably covered by the second conductive layer. The thickness of the first conductive layer is preferably 0.05 占 퐉 or more, and preferably 0.5 占 퐉 or less. The conductive particles are formed by forming a first conductive layer on the surface of the base particle and then adhering the core material on the surface of the first conductive layer and then forming a second conductive layer on the surface of the first conductive layer and the core material, Is preferably formed.

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 base metals such as graphite, and conductive polymers. Examples of the conductive polymer include polyacetylene. Examples of the non-conductive material include silica, alumina, and zirconia. Among them, a metal is preferable because the conductivity is high.

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 portion (conductive layer).

The shape of the core material is not particularly limited. The shape of the core material is preferably massive. As the core material, for example, a lump of particles, an agglomerated mass aggregating a plurality of minute particles, and a lump of an amorphous substance can be given.

The average diameter (average particle diameter) of the core material is preferably 0.001 탆 or more, more preferably 0.05 탆 or more, preferably 0.9 탆 or less, and more preferably 0.2 탆 or less. If 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 is effectively lowered.

The " average diameter (average particle diameter) " of the core material indicates a number average diameter (number average particle diameter). The average diameter of the core material is obtained by observing 50 pieces of any core material with an electron microscope or an optical microscope and calculating an average value.

The number of the protrusions per one conductive particle is preferably 3 or more, and more preferably 5 or more. The upper limit of the number of projections is not particularly limited. The upper limit of the number of protrusions can be appropriately selected in consideration of the particle diameter of the conductive particles and the like.

From the viewpoint of further improving insulation reliability and insulation reliability against impact, the average particle diameter of the second insulating particles is preferably 0.7 times or more, more preferably 1 time or more, 5 times or less, and more preferably 3 times or less.

The average height of the protrusions represents an average value of the plurality of protrusions, and the height of the protrusions is determined by assuming that there is no protrusions on the line connecting the center of the conductive particles and the tip of the protrusions (broken line L1 shown in Fig. 2) (The broken line L2 shown in Fig. 2) (on the outer surface of the spherical conductive particles when it is assumed that there is no projection) to the tip of the projection. 2, the distance from the intersection of the broken line L1 to the broken line L2 to the tip of the projection is shown.

(First and second insulating particles)

The first and second insulating particles are insulating particles. The first and second insulating particles are each smaller than the conductive particles. When the electrodes are connected to each other by using the insulating particle-attached conductive particles, shorting between adjacent electrodes can be prevented by the first and second insulating particles. Specifically, when a plurality of insulating particle-adhering conductive particles are brought into contact with each other, since the first and second insulating particles are present between the conductive particles in the plurality of insulating particle-attached conductive particles, the insulating particles are not located between the upper and lower electrodes, It is possible to prevent a short circuit between the electrodes. Further, when connecting the electrodes, the first and second insulating particles between the conductive portion and the electrode can be easily removed by pressing the insulating particle-adhering conductive particles with the two electrodes. When the projections are formed on the surface of the conductive particles, the first and second insulating particles between the conductive portion and the electrode can be more easily excluded.

Examples of the material constituting the first and second insulating particles include an insulating resin and an insulating inorganic material. Examples of the insulating resin include the resins exemplified as the resin for forming the resin particles which can be used as the base particles. Examples of the insulating inorganic material include the inorganic materials exemplified as the inorganic material for forming the inorganic particles usable as the base particles.

Specific examples of the insulating resin that is the material of the first and second insulating particles include a polyolefin, a (meth) acrylate polymer, a (meth) acrylate copolymer, a block polymer, a thermoplastic resin, a crosslinked product of a thermoplastic resin, And water-soluble resins.

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 and SBS-type styrene-butadiene block copolymer, and hydrogenated products thereof. Examples of the thermoplastic resin include a vinyl polymer and a vinyl copolymer. 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.

From the viewpoint of further increasing the releasability of the first and second insulating particles at the time of compression, the first and second insulating particles are preferably inorganic particles, and are preferably silica particles.

Examples of the inorganic particles include Siras particles, hydroxyapatite particles, magnesia particles, zirconium oxide particles and silica particles. Examples of the silica particles include pulverized silica and spherical silica. It is preferable to use spherical silica. The silica particles preferably have a functional group capable of chemically bonding to the surface, for example, a carboxyl group or a hydroxyl group, and more preferably a hydroxyl group. The inorganic particles are relatively hard, and in particular, the silica particles are relatively hard. In the case of using the insulating particle-adhering conductive particles having such hard insulating particles, when the insulating particle-attached conductive particles and the binder resin are kneaded, the hard insulating particles tends to separate from the surface of the conductive particles. In contrast, in the case of using the insulating particle-adhering conductive particles according to the present invention, it is possible to prevent the first insulating particles from being desorbed by the second insulating particles at the time of kneading even if hard first insulating particles are used . The second insulating particles serve to impart cushioning, for example. In addition, even if the first insulating particles are removed during the kneading, the second insulating particles remain, so that the insulation reliability can be secured.

It is preferable that the second insulating particles are attached to the surface of the first insulating particles through chemical bonding. It is preferable that the first insulating particles are attached to the surfaces of the conductive particles through chemical bonding. These chemical bonds include covalent bonds, hydrogen bonds, ionic bonds, coordination bonds, and the like. Among them, covalent bonding is preferable, and chemical bonding using a reactive functional group is preferable.

Examples of the reactive functional group forming the chemical bond include a vinyl group, (meth) acryloyl group, silane group, silanol group, carboxyl group, amino group, ammonium group, nitro group, hydroxyl group, carbonyl group, thiol group, sulfonic acid group, , A boric acid group, an oxazoline group, a pyrrolidone group, a phosphoric acid group and a nitrile group. Among them, a vinyl group and a (meth) acryloyl group are preferable.

From the viewpoint of further suppressing the desorption of the first insulating particles and further enhancing the insulation reliability in the connecting structure, it is preferable to use insulating particles having a reactive functional group on the surface thereof as the first insulating particles. From the viewpoint of further suppressing the desorption of the insulating particles and further enhancing the insulation reliability in the connecting structure, it is preferable to use the first insulating particles surface-treated with the compound having a reactive functional group as the first insulating particles desirable. From the viewpoint of further enhancing insulation reliability, it is preferable to use insulating particles having a reactive functional group on the surface thereof as the second insulating particles. From the viewpoint of further improving the insulation reliability, it is preferable to use the second insulating particles surface-treated with the compound having a reactive functional group as the second insulating particles.

Examples of the reactive functional group that can be introduced into the surface of the first and second insulating particles include a (meth) acryloyl group, a glycidyl group, a hydroxyl group, a vinyl group, and an amino group. The reactive functional group of the first and second insulating particles on the surface is preferably at least one reactive functional group selected from the group consisting of a (meth) acryloyl group, a glycidyl group, a hydroxyl group, a vinyl group and an amino group.

Examples of the compound (surface treatment substance) for introducing the reactive functional group include a compound having a (meth) acryloyl group, a compound having an epoxy group, and a compound having a vinyl group.

Examples of the compound (surface treatment substance) for introducing a vinyl group include a silane compound having a vinyl group, a titanium compound having a vinyl group, and a phosphoric acid compound having a vinyl group. The surface treatment material is preferably a silane compound having a vinyl group. Examples of the silane compound having a vinyl group include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, and vinyltriisopropoxysilane.

Examples of the compound (surface treatment substance) for introducing a (meth) acryloyl group include a silane compound having a (meth) acryloyl group, a titanium compound having a (meth) acryloyl group, and a phosphate compound having a (meth) acryloyl group And the like. It is also preferable that the surface treatment substance is a silane compound having a (meth) acryloyl group. Examples of the silane compound having a (meth) acryloyl group include (meth) acryloxypropyltriethoxysilane, (meth) acryloxypropyltrimethoxysilane and (meth) acryloxypropyltrimethoxysilane .

Examples of a method for attaching the first and second insulating particles to the surfaces of the conductive particles and the conductive portion include a chemical method and a physical or mechanical method. Examples of the chemical method include an interfacial polymerization method, a suspension polymerization method in the presence of particles, and an emulsion polymerization method. Examples of the physical or mechanical method include spray drying, hybridization, electrostatic deposition, spraying, dipping and vacuum deposition. However, in the hybridization method, since the first and second insulating particles tend to be easily removed, the method of disposing the first and second insulating particles is preferably a method other than the hybridization method . It is preferable that the first insulating particles are not disposed on the surface of the conductive particles by a hybridization method. It is preferable that the second insulating particles are not disposed on the surface of the conductive particles by the hybridization method. A method of disposing the first insulating particles through chemical bonding on the surface of the conductive particles is preferable because the first insulating particles become more difficult to be desorbed. A method of disposing the second insulating particles on the surface of the conductive particles through chemical bonding is preferable because the second insulating particles are more difficult to be desorbed.

Examples of a method for attaching the first and second insulating particles to the surfaces of the conductive particles and the surface of the conductive portion include the following methods.

First, conductive particles are put into 3 L of a solvent such as water, and the first and second insulating particles are gradually added while stirring. After sufficiently stirring, the insulating particle-adhering conductive particles are separated and dried by a vacuum drier or the like to obtain conductive particles with insulating particles.

It is preferable that the conductive part has a reactive functional group capable of reacting with the first insulating particles on the surface. It is preferable that the first insulating particles have a reactive functional group capable of reacting with the conductive portion on the surface. By introducing the chemical bond by the reactive functional group, the first insulating particles are unlikely to be desorbed from the surfaces of the conductive particles unintentionally. In addition, insulation reliability and insulation reliability against impact are further increased. It is preferable that the conductive portion has a reactive functional group capable of reacting with the second insulating particles on the surface. It is preferable that the second insulating particles have a reactive functional group capable of reacting with the conductive portion on the surface. By introducing the chemical bond by this reactive functional group, the second insulating particles are unlikely to be desorbed from the surface of the conductive particles unintentionally. In addition, insulation reliability and insulation reliability against impact are further increased.

As the reactive functional group, a suitable group is selected in consideration of reactivity. Examples of the reactive functional group include a hydroxyl group, a vinyl group, and an amino group. Since the reactivity is excellent, the reactive functional group is preferably a hydroxyl group. The conductive particles preferably have a hydroxyl group on their surface. The conductive portion preferably has a hydroxyl group on its surface. It is preferable that the insulating particles have a hydroxyl group on their surface.

When there is a hydroxyl group on the surface of the insulating particles and on the surface of the conductive particles, the adhesion between the first and second insulating particles and the conductive particles is suitably increased by the dehydration reaction.

Examples of the compound having a hydroxyl group include a P-OH group-containing compound and a Si-OH group-containing compound. Examples of the compound having a hydroxyl group for introducing a hydroxyl group to the surface of the insulating particles include a P-OH group-containing compound and a Si-OH group-containing compound.

Specific examples of the P-OH group-containing compound include acid phosphoxyethyl methacrylate, acid phosphoxypropyl methacrylate, acid phosphoxypolyoxyethylene glycol monomethacrylate, and acid phosphoxypolyoxypropylene glycol Monomethacrylate, and the like. The P-OH group-containing compound may be used alone, or two or more thereof may be used in combination.

Specific examples of the Si-OH group-containing compound include vinyl trihydroxysilane and 3-methacryloxypropyl trihydroxysilane. The Si-OH group-containing compound may be used alone, or two or more of them may be used in combination.

For example, the insulating particles having a hydroxyl group on the surface can be obtained by a treatment using a silane coupling agent. As the silane coupling agent, for example, hydroxytrimethoxysilane and the like can be given.

(Conductive material)

The conductive material according to the present invention includes the insulating particle-adhering conductive particles according to the present invention and a binder resin. When dispersing the conductive particle with insulating particles according to the present invention in the binder resin, it is difficult for the first and second insulating particles to separate from the surface of the conductive particle. The conductive particle with insulating particle according to the present invention is preferably dispersed in a binder resin and can be 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, an insulating resin is generally 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 a styrene-butadiene-styrene block copolymer, a styrene-isoprene-styrene block copolymer, a hydrogenated product of a styrene-butadiene-styrene block copolymer and a hydrogenated product of a styrene- Additives 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 insulating particle-containing 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 antistatic agent and a flame retardant.

As a method for dispersing the insulating particle-adhering 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 insulating particle-adhering conductive particles in the binder resin include a method of adding the insulating particle-adhered conductive particles to the binder resin and then kneading and dispersing the mixture with a planer mixer or the like; A method of homogeneously dispersing in an organic solvent using a homogenizer or the like and then adding it to the binder resin and kneading the mixture with a planer mixer or the like and a method of diluting the binder resin with water or an organic solvent, A method in which the conductive particles are added and kneaded by a planetary mixer or the like to disperse the particles.

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 conductive material according to the present invention is preferably a conductive paste. The conductive paste is excellent in handling property and circuit filling property. When a conductive paste is obtained, a relatively large force is applied to the conductive particles with insulating particles, but it is possible to prevent the insulating particles from being separated from the surface of the conductive particles by the presence of the second insulating particles.

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 insulating particle-adhering conductive particles are efficiently arranged between the electrodes, and the conduction reliability of the member to be connected connected by the conductive material is further enhanced.

The content of the insulating particle-adhering conductive particles in 100 wt% of the conductive material is preferably at least 0.01 wt%, more preferably at least 0.1 wt%, preferably at most 40 wt%, more preferably at most 20 wt% By weight, more preferably not more than 15% by weight. When the content of the insulating particle-adhering 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 connecting structure can be obtained by using the above-mentioned insulating particle-attached conductive particles or by connecting a member to be connected by using a conductive material containing the insulating particle-attached conductive particles and a binder resin.

The connection structure includes a first connection object member, a second connection object member, and a connection portion connecting the first connection object member and the second connection object member, and the connection portion is connected to the above- , Or a connection structure formed by a conductive material (anisotropic conductive material or the like) including the insulating particle-attached conductive particles and a binder resin. The first connection target member preferably has a first electrode on its surface. The second connection target member preferably has a second electrode on its surface. It is preferable that the first electrode and the second electrode are electrically connected by the conductive particles in the insulating particle-attached conductive particle. In the case of using the above-described insulating particle-adhering conductive particles, the connection itself is formed by the insulating particle-attached conductive particles. That is, the first and second connection target members are electrically connected by the conductive particles in the insulating particle-attached conductive particles.

4 is a cross-sectional view schematically showing a connection structure using the insulating particle-adhering conductive particles 1 shown in Fig.

The connection structure 81 shown in Fig. 4 has the first connection target member 82, the second connection target member 83, the first connection target member 82 and the second connection target member 83 And a connecting portion 84 connected thereto. The connecting portion 84 is formed of a conductive material including the insulating particle-attached conductive particles 1 and a binder resin. In Fig. 4, for convenience of illustration, the insulating particle-adhering conductive particles 1 are schematically shown. Instead of the insulating particle-attached conductive particles 1, the insulating particle-attached conductive particles 21 and 31 may be used.

The first connection target member 82 has a plurality of first electrodes 82a on its surface (upper surface). The second connection target member 83 has a plurality of second electrodes 83a on its front surface (lower surface). The first electrode 82a and the second electrode 83a are electrically connected to each other by the conductive particles 2 in one or a plurality of the insulating particle attachment conductive particles 1. [ Therefore, the first and second connection target members 82 and 83 are electrically connected by the conductive particles 2 in the insulating particle-adhering conductive particles 1.

The manufacturing method of the connection structure is not particularly limited. As an example of the manufacturing method of the connection structure, there can be mentioned a method of arranging the conductive material between the first connection target member and the second connection target member, obtaining a laminate, heating and pressing the laminate, and the like. The pressing pressure is about 9.8 × 10 ⁴ to 4.9 × 10 ⁶ Pa. The heating temperature is about 120 to 220 占 폚.

The first and second insulating particles 3 and 4 existing between the conductive particles 2 and the first and second electrodes 82a and 83a can be excluded when heating and pressing the laminate. The first and second insulating particles 3 and 4 existing between the conductive particles 2 and the first and second electrodes 82a and 83a are melted or deformed when heated and pressed, The surface of the conductive particles 2 is partially exposed. Part of the first and second insulating particles 3 and 4 are desorbed from the surface of the conductive particles 2 and the surface of the conductive particles 2 is partially removed from the surface of the conductive particles 2. [ It is also exposed. The first and second electrodes 82a and 83a can be electrically connected to each other through the conductive particles 2 by contacting the exposed portions of the surfaces of the conductive particles 2 with the first and second electrodes 82a and 83a have.

Specifically, examples of the member to be connected include electronic parts such as a semiconductor chip, a capacitor and a diode, and electronic parts such as a printed circuit board, a flexible printed circuit board, a glass epoxy substrate and a circuit board such as a glass substrate. It is preferable that the conductive material is a paste and is applied on the member to be connected in a paste state. It is preferable that the insulating particle-adhering conductive particles and the conductive material are used for connection of the member to be connected which is an electronic part. The connection target member is preferably an electronic component. The insulating particle-adhering conductive particles are preferably used for electrical connection of electrodes in an electronic component.

The conductive particle with insulating particles according to the present invention is suitably used for FOG, in particular, a COG using a glass substrate and a semiconductor chip as members to be connected, or a FOG using a glass substrate and a flexible printed substrate (FPC) as members to be connected. The conductive particle with insulating particle according to the present invention may be used for COG or FOG. In the connection structure according to the present invention, it is preferable that the first and second connection target members are a glass substrate and a semiconductor chip, or a glass substrate and a flexible printed substrate. The first and second connection target members may be a glass substrate and a semiconductor chip, or may be a glass substrate and a flexible printed substrate.

It is preferable that the semiconductor chip used in the COG having the glass substrate and the semiconductor chip as members to be connected be provided with bumps. The bump size is preferably in the electrode area of less than ² 1000㎛ 10000㎛ ^2. The electrode space in the semiconductor chip provided with the bumps (electrodes) is preferably 30 占 퐉 or less, more preferably 20 占 퐉 or less, and further preferably 10 占 퐉 or less. For such COG applications, the conductive particles with insulating particles according to the present invention are suitably used. In an FPC used in a FOG in which a glass substrate and a flexible printed circuit board are members to be connected, the electrode space is preferably 30 mu m or less, more preferably 20 mu m or less.

Examples of the electrode provided on the member to be connected include a metal electrode 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 circuit 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)

(Electroless plating pretreatment step)

10 g of the resin particles (average particle diameter 3 탆) formed by the copolymer resin of tetramethylolmethane tetraacrylate and divinylbenzene were subjected to alkali degreasing with an aqueous solution of sodium hydroxide, acid neutralization, a sensor in a tin dichloride solution Ting was performed.

The resin particles were treated with an ion adsorbing agent for 5 minutes and then added to an aqueous palladium sulfate solution. Thereafter, dimethylamine borane was added, followed by reduction treatment, filtration, and washing, whereby resin particles having palladium attached thereto were obtained.

(Core material compounding process)

10 g of the resin particles to which the palladium catalyst was added were dispersed in 300 ml of ion-exchanged water to prepare a dispersion. 1 g of metallic nickel particles (average particle diameter 50 nm) was added to the dispersion over 3 minutes to prepare resin particles having metallic nickel particles adhered thereto.

(Electroless nickel plating process)

Subsequently, a 1 wt% solution of sodium succinate in which sodium succinate was dissolved in 500 mL of ion-exchanged water was prepared. To this solution, 10 g of metallic nickel particles and resin particles having palladium attached thereto were added and mixed to prepare a slurry. Sulfuric acid was added to the slurry and the pH of the slurry was adjusted to 5.

An electrolytic nickel plating solution containing 10% by weight of nickel sulfate, 10% by weight of sodium hypophosphite, 4% by weight of sodium hydroxide and 20% by weight of sodium succinate was prepared as a nickel plating solution. After the slurry adjusted to pH 5 was heated to 80 ° C, an electroplating solution was continuously dropped into the slurry and stirred for 20 minutes to proceed the plating reaction. It was confirmed that no hydrogen was generated, and the plating reaction was terminated.

Subsequently, a late nickel plating solution containing 20% by weight of nickel sulfate, 5% by weight of dimethylamine borane and 5% by weight of sodium hydroxide was prepared. To the solution in which the plating reaction by the electric nickel plating solution was completed, the later nickel plating solution was continuously added dropwise and stirred for 1 hour to proceed the plating reaction. Thus, a nickel layer was formed on the surface of the resin particles to obtain conductive particles A. The thickness of the nickel layer was 0.1 mu m.

(Manufacturing process of insulating particles)

In a 1000 mL separable flask equipped with a four-neck separable cover, a stirring blade, a three-way cock, a cooling tube and a temperature probe, 45 mmol of glycidyl methacrylate, 380 mmol of methyl methacrylate, 13 mmol of dimethacrylic acid ethylene glycol, 0.5 mmol of polyoxyethylene glycol methacrylate, and 1 mmol of 2,2'-azobis {2- [N- (2-carboxyethyl) amidino] propane}. Distilled water was added to the monomer composition so that the solid content became 10% by weight, and the mixture was stirred at 150 rpm, and polymerization was carried out at 60 캜 for 24 hours under a nitrogen atmosphere. After completion of the reaction, the resultant was lyophilized to obtain first insulating particles (average particle diameter: 400 nm) having a P-OH group derived from acid phosphoxypolyoxyethylene glycol methacrylate on its surface.

Further, second insulating particles (average particle diameter 180 nm) were obtained in the same manner as above except that the stirring speed was changed to 300 rpm and the polymerization temperature was changed to 80 캜.

(Manufacturing process of conductive particles with insulating particles)

The insulating particles obtained above were each dispersed in distilled water under ultrasonic irradiation to obtain a 10 wt% aqueous dispersion of insulating particles. 10 g of the obtained conductive particle A was dispersed in 500 mL of distilled water, 3 g of the aqueous dispersion of the first insulating particles was added, and the mixture was stirred at room temperature for 30 minutes. Further, 2 g of the aqueous dispersion of the second 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, and further washed with methanol, followed by drying to obtain conductive particles with insulating particles.

As observed by a scanning electron microscope (SEM), the insulating particle-adhering conductive particles had a coating layer formed of insulating particles on the surface of the conductive particles having protrusions.

(Examples 2 to 4 and Comparative Examples 1 to 4)

The conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the amounts of the first and second insulating particles were changed to those shown in Table 1 below.

(evaluation)

(1) Coverage Z, which is the total area of the portion covered by the first and second insulating particles in the entire surface area of the conductive particle

By observing with SEM, 20 pieces of insulating particle attachment conductive particles were observed. The covering ratio which is the total projected area of the portions covered by the first and second insulating particles in the entire surface area of the conductive particles was determined. The average value of 20 coverage rates was called coverage rate Z.

(2) the total number of the second insulating particles, the number ratio of the second conductive particles arranged on the surface of the conductive particles so as to be in contact with the first insulating particles X1

In the obtained insulating-particle-adhering conductive particles, the number ratio X1 (%) of the second insulating particles disposed on the surface of the first insulating particles so as to be in contact with the conductive particles among the total number of the second insulating particles was determined. And the ratio X1 of the number was determined based on the following criteria.

[Determination Criteria of Number Ratio X1 of Second Insulating Particles Arranged on the Surface of First Insulating Particle to Contact First Insulating Particle Among Total Number of Second Insulating Particles]

A: The ratio X1 of the number is 50% or more

B: The ratio X1 is more than 30% and less than 50%

C: ratio of number X1 is 20% or more and less than 30%

D: ratio of number X1 is less than 20%

(3) The total number of the second insulating particles is set so that the number ratio of the second conductive particles X3 arranged on the surface of the conductive particles to contact the conductive particles so as not to contact the first insulating particles

In the obtained insulating-particle-adhering conductive particles, the total number of the second insulating particles is set so that the number ratio of the second insulating particles disposed on the surface of the conductive particles X 3 (%). The ratio X3 of the number was determined based on the following criteria.

[Judgment Criteria of Number Ratio X3 of Second Insulating Particles Arranged on the Surface of Electrically Conductive Particles so as not to Contact the First Insulating Particles and to Contact Conductive Particles] Among the total number of the second insulating particles,

A: The ratio X3 is 20% or more and less than 50%

B: ratio of number X3 is 10% or more and less than 20%

C: the ratio X3 is less than 10%

(4) The average number of the first insulating particles arranged on the surface of the conductive particles per one conductive particle Y1

The average number Y1 of the first insulating particles disposed on the surface of the conductive particles per one conductive particle in the obtained insulating particle-adhered conductive particle was determined. The average number Y1 was determined based on the following criteria.

[Judgment Criteria of Average Number Y1 of First Insulating Particles Arranged on the Surface of Conductive Particles per Conductive Particle]

A: The average number Y1 is 10 or more and 100 or less

B: Average number Y1 is 3 or more and less than 10

C: Average number Y1 is less than 3

(5) The average number of the second insulating particles arranged on the surface of the conductive particles per one conductive particle Y2

The average number Y2 of the second insulating particles arranged on the surface of the conductive particles per one conductive particle in the obtained insulating particle-attached conductive particle was determined. And the average number Y2 thereof was judged based on the following criteria.

[Judgment standard for the average number Y2 of the second insulating particles arranged on the surface of the conductive particles per one conductive particle]

A: The average number Y2 is 20 or more and 1000 or less

B: Average number Y2 is 6 or more and less than 20

C: Average number Y2 is less than 6

(6) The average number Y1 of the first insulating particles disposed on the surface of the conductive particles per one conductive particle, the average number of the second insulating particles disposed on the surface of the conductive particle per one conductive particle The ratio (average number Y1 / average number Y2) to Y2

In the obtained insulating particle-adhering conductive particles, the average number Y1 of the first insulating particles disposed on the surface of the conductive particles per one conductive particle, 2 (the average number Y1 / the average number Y2) with respect to the average number Y2 of the insulating particles. The above ratio (average number Y1 / average number Y2) was determined based on the following criteria.

[Judgment criteria of average number Y1 / average number Y2]

A: The ratio of the ratio (average number Y1 / average number Y2) is 0.005 or more and 0.5 or less

B: ratio (average number Y1 / average number Y2) of not less than 0.5 and not more than 1

C: ratio (average number Y1 / average number Y2) exceeds 1

(7) Conductivity (between upper and lower electrodes)

The resulting insulating particle-adhering conductive particles were added to " Strast Bond XN-5A " made by Mitsui Chemicals Co., Ltd. so that the content became 10% by weight and dispersed to obtain an anisotropic conductive paste.

A transparent glass substrate on which an ITO electrode pattern with L / S of 30 mu m / 30 mu m was formed on the upper surface was prepared. Further, a semiconductor chip in which a copper electrode pattern having L / S of 30 mu m / 30 mu m was formed on the bottom was prepared.

The resultant anisotropic conductive paste was coated on the transparent glass substrate so as to have a thickness of 30 mu m to form an anisotropic conductive paste layer. Subsequently, the semiconductor chips were stacked on the anisotropic conductive paste layer so that the electrodes were opposed to each other. Thereafter, while the temperature of the head was adjusted so that the temperature of the anisotropic conductive paste layer was 185 DEG C, a pressure heating head was placed on the upper surface of the semiconductor chip, and a pressure of 1 MPa was applied to harden the anisotropic conductive paste layer at 185 DEG C, Structure was obtained.

The connection resistances between the upper and lower electrodes of the obtained 20 connecting structures were measured by the four-terminal method, respectively. From the relationship of voltage = current x resistance, the connection resistance can be obtained by measuring the voltage when a constant current is passed. The continuity was judged based on the following criteria.

[Judgment criteria for continuity]

○○: The ratio of the number of connection structures having a resistance value of 5 or less is 90% or more

?: The number of connection structures having a resistance value of 5? Or less is 80% or more and less than 90%

?: Number of connection structures having a resistance value of 5? Or less is 60% or more and less than 80%

X: The number of connection structures having a resistance value of 5 or less is less than 60%

(8) Insulation (between adjacent electrodes in the transverse direction)

In the 20 connection structures obtained in the above (7) evaluation of continuity, the presence or absence of leakage between adjacent electrodes was evaluated by measuring the resistance with a tester. The insulation was judged based on the following criteria.

[Judgment Criteria of Insulation]

?: The number of connection structures having a resistance value of 10 ⁸ ? Or more is 80% or more

?: The number of connection structures having a resistance value of 10 ⁸ ? Or more is 60% or more and less than 80%

X: The number of connection structures having a resistance value of 10 ⁸ Ω or more is less than 60%

The results are shown in Table 1 below. In Examples 1 to 3, the ratio X1 of the numbers exceeded 50%.

1 Insulating particle attachment conductive particle
2 conductive particles
3 First insulating particles
4 Second insulating particles
11 Base particles
12 conductive parts
21 Insulating Particle-Attached Conductive Particles
22 conductive particles
26 conductive parts
27 core material
28 projection
31 Insulation Particle Attachment Conductive Particle
32 conductive particles
36 conductive parts
37 protrusion
81 connection structure
82 First object to be connected
82a first electrode
83 Second connected object member
83a second electrode
84 connection

Claims (9)

Conductive particles having at least a conductive portion on the surface,
A plurality of first insulating particles disposed on the surface of the conductive particles,
And a plurality of second insulating particles disposed on the surface of the conductive particles,
The average particle diameter of the second insulating particles is smaller than the average particle diameter of the first insulating particles,
Wherein the total coverage of the first insulating particles and the portion covered by the second insulating particles in the entire surface area of the conductive particles exceeds 50%. The insulating particle-adhering conductive particle according to claim 1, wherein 20% or more of the total number of the second insulating particles is disposed on the surface of the conductive particles so as to be in contact with the first insulating particles. The insulating particle-adhering conductive particle according to claim 1, wherein at least 50% of the total number of the second insulating particles is disposed on the surface of the conductive particles so as to contact the first insulating particles. The conductive particle according to any one of claims 1 to 3, wherein at least 10% of the total number of the second insulating particles is in contact with the conductive particles so as not to contact the first insulating particles, And the conductive particle is an insulating particle. The insulating particle-adhering conductive particle according to any one of claims 1 to 4, wherein the first insulating particles are attached to the surface of the conductive particles through a chemical bond. The conductive particles according to any one of claims 1 to 5, wherein the first insulating particles and the second insulating particles are respectively disposed on the surfaces of the conductive particles by a hybridization method, Conductive particles with insulating particles. The insulating particle-attached conductive particle according to any one of claims 1 to 6, wherein the conductive particles have protrusions on the outer surface of the conductive portion. A conductive material comprising the insulating particle-adhering conductive particles according to any one of claims 1 to 7 and a binder resin. A first connection target member having a first electrode on its surface,
A second connection target member having a second electrode on its surface,
And a connecting portion connecting the first connection target member and the second connection target member,
Wherein the connection portion is formed by the conductive particles having the insulating particle according to any one of Claims 1 to 7 or formed of a conductive material including the conductive particle having the insulating particle and the binder resin,
Wherein the first electrode and the second electrode are electrically connected by the conductive particles in the insulating particle-attached conductive particle.

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