WO2022239776A1 - Conductive particles, conductive material, and connection structure - Google Patents

Conductive particles, conductive material, and connection structure Download PDF

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Publication number
WO2022239776A1
WO2022239776A1 PCT/JP2022/019834 JP2022019834W WO2022239776A1 WO 2022239776 A1 WO2022239776 A1 WO 2022239776A1 JP 2022019834 W JP2022019834 W JP 2022019834W WO 2022239776 A1 WO2022239776 A1 WO 2022239776A1
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WIPO (PCT)
Prior art keywords
conductive
particles
flux
particle
conductive particles
Prior art date
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PCT/JP2022/019834
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French (fr)
Japanese (ja)
Inventor
豪 湯川
Original Assignee
積水化学工業株式会社
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Publication date
Application filed by 積水化学工業株式会社 filed Critical 積水化学工業株式会社
Priority to CN202280034394.5A priority Critical patent/CN117296109A/en
Priority to JP2022538328A priority patent/JPWO2022239776A1/ja
Priority to KR1020237026386A priority patent/KR20240006491A/en
Publication of WO2022239776A1 publication Critical patent/WO2022239776A1/en

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B5/00—Non-insulated conductors or conductive bodies characterised by their form
    • H01B5/16—Non-insulated conductors or conductive bodies characterised by their form comprising conductive material in insulating or poorly conductive material, e.g. conductive rubber
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H01B1/02—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors mainly consisting of metals or alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B1/00—Conductors or conductive bodies characterised by the conductive materials; Selection of materials as conductors
    • H01B1/20—Conductive material dispersed in non-conductive organic material
    • H01B1/22—Conductive material dispersed in non-conductive organic material the conductive material comprising metals or alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
    • H01B3/30—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances plastics; resins; waxes
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B5/00—Non-insulated conductors or conductive bodies characterised by their form
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01R—ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R11/00—Individual connecting elements providing two or more spaced connecting locations for conductive members which are, or may be, thereby interconnected, e.g. end pieces for wires or cables supported by the wire or cable and having means for facilitating electrical connection to some other wire, terminal, or conductive member, blocks of binding posts
    • H01R11/01—Individual connecting elements providing two or more spaced connecting locations for conductive members which are, or may be, thereby interconnected, e.g. end pieces for wires or cables supported by the wire or cable and having means for facilitating electrical connection to some other wire, terminal, or conductive member, blocks of binding posts characterised by the form or arrangement of the conductive interconnection between the connecting locations

Definitions

  • the present invention relates to conductive particles using flux.
  • the present invention also relates to a conductive material and a connection structure using the conductive particles.
  • Anisotropic conductive materials such as anisotropic conductive paste and anisotropic conductive film are widely known.
  • anisotropic conductive material conductive particles are dispersed in a binder resin.
  • the anisotropic conductive material is used to obtain various connection structures.
  • Examples of the connection using the anisotropic conductive material include connection between a flexible printed circuit board and a glass substrate (FOG (Film on Glass)), connection between a semiconductor chip and a flexible printed circuit board (COF (Chip on Film)), Examples include connection between a semiconductor chip and a glass substrate (COG (Chip on Glass)) and connection between a flexible printed circuit board and a glass epoxy substrate (FOB (Film on Board)).
  • an anisotropic conductive material containing conductive particles is placed on the glass epoxy board. do.
  • the flexible printed circuit board is laminated and heated and pressurized. As a result, the anisotropic conductive material is cured and the electrodes are electrically connected via the conductive particles to obtain a connection structure.
  • an oxide film may be formed on the surface of the conductive portion of the conductive particles depending on storage conditions before conductive connection. Also, an oxide film may be formed on the surface of the electrodes to be electrically connected. The presence of this oxide film causes an increase in connection resistance and a decrease in conduction reliability in a connection structure that is electrically connected. In order to remove the oxide film on the surfaces of the conductive particles and the electrodes, flux may be added to the anisotropic conductive material or placed on the surfaces of the conductive particles.
  • Patent Document 1 discloses a conductive adhesive composition containing (A) conductive particles containing a metal having a melting point of 220° C. or lower, (B) a thermosetting resin, and (C) a flux activator. It is (C) The flux activator has an average particle size of 15 ⁇ m or less.
  • Patent Document 2 discloses an anisotropic conductive film having metal particles in an insulating film.
  • the metal particles are regularly arranged in plan view, and at least one end of the metal particles on the front side of the anisotropic conductive film or the back side of the anisotropic conductive film is arranged so that the flux is in contact with or close to
  • the flux is in contact with or close to the ends of the metal particles.
  • a plurality of upper electrodes and a plurality of lower electrodes are electrically connected to form a conductive connection.
  • the conductive particles are preferably located between the top and bottom electrodes and not between adjacent lateral electrodes. It is desirable that there is no electrical connection between adjacent lateral electrodes.
  • An object of the present invention is to effectively remove the oxide film on the surface of the conductive particles and the surface of the electrodes, and to effectively increase the reliability of conduction when the electrodes are electrically connected.
  • An object of the present invention is to provide conductive particles capable of Another object of the present invention is to provide a conductive material and a connection structure using the conductive particles.
  • a conductive particle body, a plurality of flux-containing particles, and a flux film are provided, and the conductive particle body is disposed outside the substrate particles and the substrate particles. and a conductive portion, wherein the flux-containing particles are arranged outside the conductive particle body, and the flux film is arranged outside the conductive particle body.
  • the flux-containing particles contain particle bodies and flux, and the particle bodies are resin particles.
  • the material of the resin particles contains a polymerizable monomer, and the homopolymer of the polymerizable monomer has a glass transition temperature of 80° C. or higher. .
  • the flux-containing particles have a breaking point in the compression-displacement curve when a maximum test load of 3.3 mN is applied to the flux-containing particles for 10 seconds. do not do.
  • the conductive portion contains tin.
  • the ratio of the particle size of the conductive particles to the particle size of the flux-containing particles is 3 or more and 500 or less.
  • the conductive particles have a particle diameter of 1 ⁇ m or more and 50 ⁇ m or less.
  • the residual rate of flux-containing particles determined by the following formula (1) is 99% or less.
  • Remaining rate of flux-containing particles (coverage rate of flux-containing particles after ultrasonic treatment/coverage rate of flux-containing particles before ultrasonic treatment) x 100... formula (1)
  • a broad aspect of the present invention provides a conductive material containing the above-described conductive particles and a binder resin.
  • a first member to be connected having a first electrode on its surface
  • a second member to be connected having a second electrode on its surface
  • the first member to be connected a connecting portion connecting the second member to be connected, wherein the material of the connecting portion contains the conductive particles described above, and the first electrode and the second electrode are electrically conductive.
  • a connection structure is provided that is electrically connected by the particle bodies.
  • a conductive particle according to the present invention comprises a conductive particle body, a plurality of flux-containing particles, and a flux film.
  • the conductive particle main body includes a substrate particle and a conductive portion arranged outside the substrate particle.
  • the flux-containing particles are arranged outside the conductive particle body, and the flux film is arranged outside the conductive particle body. Since the conductive particles according to the present invention have the above configuration, the oxide film on the surfaces of the conductive particles and the electrodes can be effectively removed, and the electrodes are electrically connected. In this case, the conduction reliability can be effectively improved.
  • FIG. 1 is a cross-sectional view showing conductive particles according to a first embodiment of the present invention.
  • FIG. 2 is a cross-sectional view showing conductive particles according to a second embodiment of the present invention.
  • FIG. 3 is a cross-sectional view showing conductive particles according to a third embodiment of the present invention.
  • FIG. 4 is a cross-sectional view showing conductive particles according to a fourth embodiment of the present invention.
  • FIG. 5 is a cross-sectional view schematically showing a connected structure using conductive particles according to the first embodiment of the present invention.
  • a conductive particle according to the present invention includes a conductive particle body, a plurality of flux-containing particles, and a flux film.
  • the conductive particle main body includes a substrate particle and a conductive portion arranged outside the substrate particle.
  • the flux-containing particles are arranged outside the conductive particle body, and the flux film is arranged outside the conductive particle body.
  • the conductive particles according to the present invention have the above configuration, the surface of the conductive particles (specifically, the surface of the conductive portion of the conductive particles) and the oxide film on the surface of the electrode are effectively removed. When it can be removed and the electrodes are electrically connected, the reliability of conduction can be effectively improved.
  • the entire flux component is quickly activated on the surface of the conductive particles or electrodes due to heating and pressurization during conductive connection, and the flux tends to lose its activating ability early. For this reason, it may not be possible to sufficiently remove the oxide film on the surface of the conductive particles. As a result, the connection resistance between the upper and lower electrodes to be connected increases, and the reliability of conduction may decrease.
  • the oxide film on the surface of the conductive particles and the surface of the electrode is effectively removed by the flux film in the initial stage of conductive connection by heating and pressurizing at the time of conductive connection. be able to.
  • the flux gradually leaks from the flux-containing particles due to heating and pressurization at the time of conductive connection. can be removed.
  • the flux gradually leaks from the flux-containing particles even after the conductive connection, so that the oxide film on the surface of the conductive particles and the surface of the electrode can be removed. As a result, it is possible to effectively improve the reliability of conduction between the upper and lower electrodes to be connected.
  • the flux-containing particles are easily detached from the upper and lower surfaces of the conductive particle body due to the vertical mounting stress applied to the conductive particles during conductive connection. This makes it difficult for the flux-containing particles to remain between the conductive particle body and the electrode, and as a result, it is possible to effectively improve the reliability of conduction between the upper and lower electrodes to be connected.
  • the flux-containing particles are less likely to detach from the surfaces in the horizontal direction of the main body of the conductive particles. As a result, the conductive particles according to the present invention can effectively improve the insulation reliability between laterally adjacent electrodes that should not be connected.
  • the present invention since the present invention has the above configuration, it is possible to reduce the flux content compared to conventional conductive particles and conductive materials.
  • the oxide film on the surface of the conductive particles and the surface of the electrode can be effectively removed, and when the electrodes are electrically connected, the conduction reliability is effectively improved. can be increased to
  • the conductive particles are dispersed in a binder resin and are suitably used to obtain a conductive material.
  • FIG. 1 is a cross-sectional view showing conductive particles according to the first embodiment of the present invention.
  • the conductive particle 1 shown in FIG. 1 includes a conductive particle body 11, a plurality of flux-containing particles 12, and a flux film 13.
  • the conductive particle body 11 includes the base particle 21 and the conductive part 22 arranged outside the base particle 21 .
  • the flux-containing particles 12 are arranged outside the conductive particle body 11 .
  • the flux film 13 is arranged outside the conductive particle body 11 .
  • the conductive portion 22 is arranged on the surface of the substrate particle 21 and is in contact with the substrate particle 21 .
  • the flux-containing particles 12 are arranged on the surface of the conductive particle body 11 (conductive portion 22) and are in contact with the conductive particle body 11 (conductive portion 22).
  • the flux film 13 is arranged on the surface of the conductive particle body 11 (conductive portion 22) and is in contact with the conductive particle body 11 (conductive portion 22).
  • the conductive portion 22 covers the surfaces of the base particles 21 .
  • the conductive particle body 11 is a coated particle in which the surface of the base particle 21 is coated with the conductive part 22 .
  • the conductive particle body 11 has a conductive portion 22 on its surface.
  • the conductive portion 22 is a conductive layer.
  • the conductive portion 22 is a single-layer conductive layer.
  • the conductive portion may cover the entire surface of the substrate particle, or the conductive portion may cover a portion of the surface of the substrate particle.
  • the flux film 13 covers the surface of the conductive particle body 11 (the surface of the conductive portion 22 ) and the surface of the flux-containing particles 12 .
  • the conductive particles 1 can be obtained, for example, by using the conductive particle body 11 to which the flux-containing particles 12 are attached before the flux film 13 is arranged, and forming the flux film 13 by flux treatment.
  • Conductive particles 1B and 1C, which will be described later, can also be obtained in the same manner as the conductive particles 1.
  • FIG. 2 is a cross-sectional view showing conductive particles according to the second embodiment of the present invention.
  • a conductive particle 1A shown in FIG. 2 includes a conductive particle body 11A, a plurality of flux-containing particles 12A, and a flux film 13A.
  • the conductive particle main body 11A includes a base particle 21A and a conductive portion 22A arranged outside the base particle 21A.
  • the flux-containing particles 12A are arranged outside the conductive particle body 11A.
  • the flux film 13A is arranged outside the conductive particle main body 11A.
  • the conductive portion 22A is arranged on the surface of the substrate particle 21A and is in contact with the substrate particle 21A.
  • the flux-containing particles 12A are arranged on the surface of the conductive particle body 11A (conductive portion 22A) via the flux film 13A.
  • flux-containing particles 12A are arranged on the surface of flux film 13A.
  • the flux-containing particles 12A are not in contact with the conductive particle body 11A, but are in contact with the flux film 13A.
  • the flux film 13A is arranged on the surface of the conductive particle body 11A (conductive portion 22A) and is in contact with the conductive particle body 11A (conductive portion 22A).
  • the flux film 13A covers only the surface of the conductive particle body 11A (the surface of the conductive portion 22A).
  • the flux film 13A does not cover the surfaces of the flux-containing particles 12A.
  • the flux film 13A is arranged between the conductive particle body 11A and the flux-containing particles 12A.
  • the conductive particles 1 and the conductive particles 1A have different configurations of the flux-containing particles and the flux film.
  • the flux film may or may not exist between the flux-containing particles and the conductive portion.
  • the flux film may or may not cover the surface of the flux-containing particles.
  • the flux-containing particles 12A and the conductive particle main body 11A before the flux film 13A is arranged are used to form the flux film 13A by a flux treatment, and then the flux-containing particles 12A are applied to the flux film 13A. You can get it by attaching it.
  • FIG. 3 is a cross-sectional view showing conductive particles according to a third embodiment of the present invention.
  • a conductive particle 1B shown in FIG. 3 includes a conductive particle body 11B, a plurality of flux-containing particles 12B, and a flux film 13B.
  • the conductive particle main body 11B includes the base particle 21B and the conductive part 22B arranged outside the base particle 21B.
  • the flux-containing particles 12B are arranged outside the conductive particle body 11B.
  • the flux film 13B is arranged outside the conductive particle main body 11B.
  • the conductive portion 22B is arranged on the surface of the substrate particle 21B and is in contact with the substrate particle 21B.
  • the conductive portion 22B is a two-layered conductive layer.
  • the conductive portion 22B includes a first conductive portion 22BA and a second conductive portion 22BB.
  • the first conductive portions 22BA are arranged outside the base particles 21B, and the second conductive portions 22BB are arranged outside the first conductive portions 22BA.
  • the first conductive portion 22BA is laminated on the surface of the substrate particle 21B, and the second conductive portion 22BB is laminated on the surface of the first conductive portion 22BA.
  • the configuration of the conductive portion is different between the conductive particles 1 and the conductive particles 1B.
  • the conductive portion may be a single conductive layer or multiple conductive layers.
  • FIG. 4 is a cross-sectional view showing conductive particles according to the fourth embodiment of the present invention.
  • a conductive particle 1C shown in FIG. 4 includes a conductive particle body 11C, a plurality of flux-containing particles 12C, and a flux film 13C.
  • the conductive particle body 11C is composed of a base particle 21C, a conductive portion 22C arranged outside the base particle 21C, and a plurality of core substances 23C arranged outside the base particle 21C.
  • the conductive portion 22C covers the substrate particles 21C and the core substance 23C.
  • the conductive particle main body 11C has a plurality of protrusions 11Ca on the surface.
  • the core material 23C raises the surface of the conductive portion 22C, forming a plurality of projections 11Ca.
  • the conductive particles 1 and 1C differ in the presence or absence of the use of a core substance and the presence or absence of protrusions on the conductive particle body.
  • the conductive particle body may or may not have projections on the surface.
  • (meth)acrylate indicates acrylate and methacrylate.
  • (Meth)acryl indicates acryl and methacryl.
  • (Meth)acryloyl indicates acryloyl and methacryloyl.
  • the particle diameter of the conductive particles is preferably 1 ⁇ m or more, more preferably 10 ⁇ m or more, and preferably 50 ⁇ m or less, more preferably 40 ⁇ m or less.
  • the particle diameter of the conductive particles is the lower limit or more and the upper limit or less, when the electrodes are connected using the conductive particles, the contact area between the conductive particles and the electrodes is sufficiently large, In addition, it becomes difficult to form agglomerated conductive particles when forming the conductive portion. Also, the distance between the electrodes connected via the conductive particle main body does not become too large, and the conductive portion is less likely to peel off from the surface of the base particle.
  • the particle diameter of the conductive particle main body is preferably 1 ⁇ m or more, more preferably 10 ⁇ m or more, and preferably 50 ⁇ m or less, more preferably 40 ⁇ m or less.
  • the particle diameter of the conductive particle body is at least the lower limit and at most the upper limit, when the electrodes are connected using the conductive particle, the contact area between the conductive particle body and the electrode is sufficiently large.
  • the distance between the electrodes connected via the conductive particle main body does not become too large, and the conductive portion is less likely to peel off from the surface of the base particle.
  • the particle size of the conductive particles and the conductive particle main body is preferably an average particle size, and the average particle size indicates a number average particle size.
  • the particle diameters of the conductive particles and the conductive particle main body are, for example, 50 arbitrary conductive particles are observed with an electron microscope or an optical microscope, and the average particle diameter of each conductive particle and each conductive particle main body. It can be obtained by calculating the value or performing laser diffraction particle size distribution measurement.
  • the coefficient of variation (CV value) of the particle size of the conductive particles and the conductive particle main body is preferably 10% or less, more preferably 5%. It is below.
  • the coefficient of variation (CV value) can be measured as follows.
  • CV value (%) ( ⁇ /Dn) ⁇ 100 ⁇ : standard deviation of the particle size of the conductive particles or the main body of the conductive particles Dn: the average value of the particle size of the conductive particles or the main body of the conductive particles
  • the shape of the conductive particles and the main body of the conductive particles is not particularly limited.
  • the conductive particles and the conductive particle main body may have a spherical shape, a shape other than a spherical shape, or a flat shape.
  • the substrate particles include resin particles, inorganic particles other than metal particles, organic-inorganic hybrid particles, and metal particles.
  • the substrate particles are preferably substrate particles other than metal particles, and more preferably resin particles, inorganic particles other than metal particles, or organic-inorganic hybrid particles.
  • the substrate particles may be core-shell particles comprising a core and a shell arranged on the surface of the core.
  • the core may be an organic core and the shell may be an inorganic shell.
  • Materials for the resin particles include polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene, and polybutadiene; acrylic resins such as polymethyl methacrylate and polymethyl acrylate; polycarbonate, polyamide, and phenol formaldehyde.
  • polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene, and polybutadiene
  • acrylic resins such as polymethyl methacrylate and polymethyl acrylate
  • polycarbonate polyamide
  • phenol formaldehyde phenol formaldehyde
  • Resin melamine formaldehyde resin, benzoguanamine formaldehyde resin, urea formaldehyde resin, phenolic resin, melamine resin, benzoguanamine resin, urea resin, epoxy resin, unsaturated polyester resin, saturated polyester resin, polyethylene terephthalate, polysulfone, polyphenylene oxide, polyacetal, polyimide, Examples include polyamideimide, polyetheretherketone, polyethersulfone, and divinylbenzene polymer.
  • the divinylbenzene polymer may be a divinylbenzene copolymer.
  • the divinylbenzene copolymer and the like examples include a divinylbenzene-styrene copolymer and a divinylbenzene-(meth)acrylate copolymer. Since the hardness of the resin particles can be easily controlled within a suitable range, the material of the resin particles is a polymer obtained by polymerizing one or more polymerizable monomers having an ethylenically unsaturated group. is preferred.
  • the polymerizable monomer having an ethylenically unsaturated group may be a non-crosslinking monomer. and crosslinkable monomers.
  • non-crosslinkable monomers examples include styrene and styrene-based monomers such as ⁇ -methylstyrene; carboxyl group-containing monomers such as (meth)acrylic acid, maleic acid, and maleic anhydride; methyl ( meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl ( Alkyl (meth)acrylate compounds such as meth)acrylate and isobornyl (meth)acrylate; 2-hydroxyethyl (meth)acrylate, glycerol (meth)acrylate, polyoxyethylene (meth)acrylate, and glycidyl (meth)acrylate, etc.
  • carboxyl group-containing monomers
  • crosslinkable monomer examples include tetramethylolmethane tetra(meth)acrylate, tetramethylolmethane tri(meth)acrylate, tetramethylolmethane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol hexa (meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol poly(meth)acrylate, pentaerythritol tetra(meth)acrylate, glycerol tri(meth)acrylate, glycerol di(meth)acrylate, (poly)ethylene glycol Polyfunctional (meth)acrylate compounds such as di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, (poly)tetramethylene glycol di(meth)acrylate, and 1,4-butanedio
  • the crosslinkable monomers include (poly)ethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, penta Erythritol tetra(meth)acrylate or dipentaerythritol poly(meth)acrylate is preferred.
  • the resin particles can be obtained by polymerizing the polymerizable monomer having the ethylenically unsaturated group by a known method. Examples of this method include a method of suspension polymerization in the presence of a radical polymerization initiator, and a method of polymerizing by swelling a monomer together with a radical polymerization initiator using uncrosslinked seed particles.
  • the substrate particles are inorganic particles excluding metals or organic-inorganic hybrid particles
  • examples of inorganic substances for forming the substrate particles include silica, alumina, barium titanate, zirconia, and carbon black.
  • the inorganic substance is not a metal.
  • the particles formed of silica can be obtained, for example, by hydrolyzing a silicon compound having two or more hydrolyzable alkoxysilyl groups to form crosslinked polymer particles, followed by firing as necessary. particles that can be used.
  • the organic-inorganic hybrid particles include organic-inorganic hybrid particles formed from a crosslinked alkoxysilyl polymer and an acrylic resin.
  • the organic-inorganic hybrid particles are preferably core-shell type organic-inorganic hybrid particles having a core and a shell disposed on the surface of the core. It is preferred that the core is an organic core. Preferably, the shell is an inorganic shell. From the viewpoint of effectively reducing the connection resistance between electrodes, the substrate particles are preferably organic-inorganic hybrid particles having an organic core and an inorganic shell disposed on the surface of the organic core.
  • Examples of the material for the organic core include the materials for the resin particles described above.
  • the material for the inorganic shell examples include the inorganic substances listed above as the material for the substrate particles.
  • the inorganic shell material is preferably silica.
  • the inorganic shell is preferably formed by forming a metal alkoxide into a shell-like material on the surface of the core by a sol-gel method, and then firing the shell-like material.
  • the metal alkoxide is preferably silane alkoxide.
  • the inorganic shell is preferably made of silane alkoxide.
  • the substrate particles are metal particles
  • examples of metals that are materials of the metal particles include silver, copper, nickel, silicon, gold, and titanium.
  • the particle diameter of the substrate particles is preferably 0.5 ⁇ m or more, more preferably 9.5 ⁇ m or more, and preferably 49.95 ⁇ m or less, more preferably 39.95 ⁇ m or less.
  • the particle size of the substrate particles is equal to or more than the lower limit and equal to or less than the upper limit, small conductive particles can be obtained even when the distance between the electrodes is small and the thickness of the conductive portion is increased. Furthermore, it becomes difficult to aggregate when forming the conductive portion on the surface of the substrate particles, and it becomes difficult to form aggregated conductive particles.
  • the shape of the substrate particles is not particularly limited.
  • the shape of the substrate particles may be spherical, may be other than spherical, or may be flat.
  • the particle size of the substrate particles is preferably the average particle size, and the average particle size indicates the number average particle size.
  • the particle size of the substrate particles is determined using a particle size distribution analyzer or the like.
  • the particle diameter of the substrate particles is preferably determined by observing 50 arbitrary substrate particles with an electron microscope or an optical microscope and calculating the average value. When measuring the particle size of the substrate particles of the conductive particles, it can be measured, for example, as follows.
  • the conductive particle body preferably has projections on the outer surface of the conductive portion. It is preferable that the protrusion is plural.
  • an oxide film is often formed on the surface of the electrode that contacts the main body of the conductive particles.
  • the oxide film can be effectively removed by the projections at the time of conductive connection.
  • the electrode and the conductive portion can be brought into contact with each other more reliably, the contact area between the conductive particle body and the electrode can be sufficiently increased, and the connection resistance can be more effectively reduced.
  • the protrusions of the conductive particle bodies can more effectively eliminate the binder between the conductive particle bodies and the electrode. Therefore, the contact area between the conductive particle body and the electrode can be sufficiently increased, and the connection resistance can be further effectively reduced.
  • the conductive particle main body preferably has a core substance on the outside of the substrate particles.
  • the conductive particle body preferably has a core substance on the surface of the substrate particle.
  • Examples of methods for forming projections on the surface of the conductive particle body include the following methods.
  • the core substance is added to the dispersion liquid of the substrate particles, and the core substance is accumulated on the surface of the substrate particles by, for example, Van der Waals force. and a method of adding the core substance to a container containing the base particles and attaching the core substance to the surface of the base particles by mechanical action such as rotation of the container.
  • the method of accumulating and attaching the core substance to the surface of the substrate particles in the dispersion liquid is preferable because the amount of the core substance to be adhered can be easily controlled.
  • the conductive particles may have a first conductive portion on the outside of the base particles and a second conductive portion on the outside of the first conductive portion.
  • a core substance may be adhered to the surface of the first conductive portion.
  • the core substance is preferably covered with the second conductive portion.
  • the short diameter of the core substance is preferably 0.05 ⁇ m or more and preferably 0.5 ⁇ m or less.
  • the conductive particles form the first conductive portion on the surface of the substrate particle, then attach the core substance on the surface of the first conductive portion, and then the surface of the first conductive portion and the core substance It is preferably obtained by forming a second conductive portion thereon.
  • Conductive substances and non-conductive substances can be mentioned as substances that constitute the core substance.
  • the conductive substance include metals, metal oxides, conductive nonmetals such as graphite, and conductive polymers. Polyacetylene etc. are mentioned as said conductive polymer. Silica, alumina, zirconia, and the like are mentioned as the non-conductive substance. From the standpoint of enhancing conduction reliability, the substance constituting the core substance is preferably a metal.
  • the core substance is preferably metal particles.
  • metals examples include metals such as gold, silver, copper, platinum, zinc, iron, lead, tin, aluminum, cobalt, indium, nickel, chromium, titanium, antimony, bismuth, germanium and cadmium, and tin-lead. alloys, tin-copper alloys, tin-silver alloys, tin-lead-silver alloys, and alloys composed of two or more metals such as tungsten carbide. Among them, nickel, copper, silver or gold is preferable.
  • the metal forming the core substance may be the same as or different from the metal forming the conductive portion (conductive layer).
  • the shape of the core substance is not particularly limited.
  • the shape of the core substance is preferably massive.
  • the core substance includes, for example, particulate lumps, agglomerates in which a plurality of microparticles are aggregated, irregular lumps, and the like.
  • the average height of the plurality of projections is preferably 0.001 ⁇ m or more, more preferably 0.05 ⁇ m or more, preferably 0.9 ⁇ m or less, more preferably 0.2 ⁇ m or less.
  • the connection resistance between the electrodes can be effectively lowered.
  • the conductive particles have conductive portions on their surfaces.
  • the conductive portion is arranged on the surface of the substrate particle.
  • the conductive portion preferably contains a metal.
  • the metal forming the conductive portion is not particularly limited. Examples of the metals include tin, gold, silver, copper, tin, platinum, palladium, zinc, lead, aluminum, cobalt, indium, nickel, chromium, titanium, antimony, bismuth, germanium, cadmium, and alloys thereof. be done. Alternatively, tin-doped indium oxide (ITO) may be used as the metal. Only one of the above metals may be used, or two or more thereof may be used in combination.
  • ITO tin-doped indium oxide
  • the conductive portion preferably contains tin, nickel, copper or gold, more preferably tin or nickel, and still more preferably tin.
  • the conductive portion preferably contains tin as a main metal.
  • the tin content is preferably 10% by weight or more in 100% by weight of the conductive portion.
  • the content of tin in 100% by weight of the conductive portion is preferably 15% by weight or more, more preferably 20% by weight or more, further preferably 25% by weight or more, and particularly preferably 25% by weight or more. is 30% by weight or more.
  • the content of tin in 100% by weight of the conductive portion may be 100% by weight (total amount).
  • the conductive portion may be formed of one layer.
  • the conductive portion may be formed of a plurality of layers. That is, the conductive portion may have a laminated structure of two or more layers.
  • the metal constituting the outermost layer is preferably tin, nickel or gold, more preferably tin or nickel, and tin. More preferred.
  • the connection resistance between the electrodes is even lower. Further, when the metal forming the outermost layer is gold, the corrosion resistance is further enhanced.
  • the area (coverage) of the conductive portion is preferably 80% or more, more preferably 90% or more.
  • the upper limit of the coverage rate is not particularly limited. The coverage may be 99% or less. When the coverage is equal to or more than the lower limit and equal to or less than the upper limit, it is possible to further effectively improve the conduction reliability when the electrodes are electrically connected.
  • the thickness of the conductive portion is preferably 0.005 ⁇ m or more, more preferably 0.01 ⁇ m or more, and preferably 10 ⁇ m or less, more preferably 1 ⁇ m or less, and even more preferably 0.5 ⁇ m or less.
  • the thickness of the conductive portion is equal to or more than the lower limit and equal to or less than the upper limit, the reliability of conduction is further effectively improved, and the conductive particles do not become too hard, so that the conductive particles can be electrically conductive when connecting between electrodes. Particles can be sufficiently deformed.
  • the thickness of the conductive portion in the outermost layer is preferably 0.001 ⁇ m or more, more preferably 0.01 ⁇ m or more, and preferably 0.5 ⁇ m or less, and more preferably. is 0.3 ⁇ m or less.
  • the thickness of the conductive portion of the outermost layer is equal to or more than the lower limit and equal to or less than the upper limit, the conductive portion of the outermost layer is uniform, the corrosion resistance is sufficiently high, and the connection resistance between electrodes is sufficiently low. can do.
  • the thickness of the conductive portion can be measured, for example, by observing the cross section of the conductive particles using a transmission electron microscope (TEM).
  • TEM transmission electron microscope
  • the method of forming the conductive portion on the surface of the substrate particles is not particularly limited.
  • Methods for forming the conductive portion include, for example, a method by electroless plating, a method by electroplating, a method by physical collision, a method by mechanochemical reaction, a method by physical vapor deposition or physical adsorption, and metal powder or Examples thereof include a method of coating the surface of the substrate particles with a paste containing a metal powder and a binder.
  • the method of forming the conductive portion is preferably electroless plating, electroplating, or a method using physical collision. Methods such as vacuum deposition, ion plating, and ion sputtering can be used as the method by physical vapor deposition. Also, in the method using physical collision, for example, a sheeter composer (manufactured by Tokuju Kosakusho Co., Ltd.) or the like is used.
  • the conductive particles comprise flux-containing particles.
  • the flux-containing particles are arranged outside the conductive particle body.
  • the flux-containing particles are arranged on the surface of the conductive particle body.
  • the flux-containing particles are arranged on the surface of the conductive portion.
  • the flux-containing particles may be arranged on the surface of the conductive particle body or the conductive portion via a flux film or the like.
  • the flux-containing particles may be in contact with the surface of the conductive particle body, or may not be in contact with the surface of the conductive particle body.
  • the flux-containing particles may be in contact with the surface of the conductive portion, or may not be in contact with the surface of the conductive portion.
  • the flux-containing particles preferably contain a particle body and flux.
  • the particle main body examples include inorganic particles other than metal particles, resin particles, organic-inorganic hybrid particles, metal particles, and the like.
  • the particle bodies are preferably inorganic particles other than metal particles or resin particles, and more preferably resin particles.
  • inorganic particles other than the metal particles examples include silica, alumina, and titania. Porous silica etc. are mentioned as said silica.
  • Materials for the resin particles include polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene, and polybutadiene; acrylic resins such as polymethyl methacrylate and polymethyl acrylate; polycarbonate, polyamide, and phenol formaldehyde.
  • polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene, and polybutadiene
  • acrylic resins such as polymethyl methacrylate and polymethyl acrylate
  • polycarbonate polyamide
  • phenol formaldehyde phenol formaldehyde
  • Resin melamine formaldehyde resin, benzoguanamine formaldehyde resin, urea formaldehyde resin, phenolic resin, melamine resin, benzoguanamine resin, urea resin, epoxy resin, unsaturated polyester resin, saturated polyester resin, polyethylene terephthalate, polysulfone, polyphenylene oxide, polyacetal, polyimide, Examples include polyamideimide, polyetheretherketone, polyethersulfone, and divinylbenzene polymer.
  • the divinylbenzene polymer may be a divinylbenzene copolymer.
  • the divinylbenzene copolymer and the like examples include a divinylbenzene-styrene copolymer and a divinylbenzene-(meth)acrylate copolymer. Since the hardness of the resin particles can be easily controlled within a suitable range, the material of the resin particles preferably contains a polymerizable monomer. More preferably, it is a polymer obtained by polymerizing two or more kinds.
  • the polymerizable monomer having an ethylenically unsaturated group may be a non-crosslinking monomer. and crosslinkable monomers.
  • non-crosslinkable monomers examples include styrene and styrene-based monomers such as ⁇ -methylstyrene; carboxyl group-containing monomers such as (meth)acrylic acid, maleic acid, and maleic anhydride; methyl ( meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl ( Alkyl (meth)acrylate compounds such as meth)acrylate and isobornyl (meth)acrylate; 2-hydroxyethyl (meth)acrylate, glycerol (meth)acrylate, polyoxyethylene (meth)acrylate, and glycidyl (meth)acrylate, etc.
  • carboxyl group-containing monomers
  • crosslinkable monomer examples include tetramethylolmethane tetra(meth)acrylate, tetramethylolmethane tri(meth)acrylate, tetramethylolmethane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol hexa (meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol poly(meth)acrylate, pentaerythritol tetra(meth)acrylate, glycerol tri(meth)acrylate, glycerol di(meth)acrylate, (poly)ethylene glycol Polyfunctional (meth)acrylate compounds such as di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, (poly)tetramethylene glycol di(meth)acrylate, and 1,4-butanedio
  • the resin particles can be obtained by polymerizing the polymerizable monomer having the ethylenically unsaturated group by a known method. Examples of this method include a method of suspension polymerization in the presence of a radical polymerization initiator, and a method of polymerizing by swelling a monomer together with a radical polymerization initiator using uncrosslinked seed particles.
  • the glass transition temperature of the homopolymer of the polymerizable monomer is preferably 40° C. or higher, more preferably 50° C. or higher, still more preferably 80° C. or higher, and preferably 250° C. or lower, more preferably 230° C. or lower. , and more preferably 200° C. or less.
  • the glass transition temperature of the homopolymer of the polymerizable monomer is above the lower limit and below the upper limit, the flux gradually leaks out from the flux-containing particles due to heating and pressurization during conductive connection. As a result, the oxide film on the surface of the conductive particles and the surface of the electrode can be removed more effectively, and the reliability of conduction is more effectively improved when the electrodes are electrically connected. be able to.
  • the glass transition temperature of the homopolymer of the polymerizable monomer having the highest content on a weight basis is preferably at least the above lower limit, and at most the above upper limit. Preferably.
  • the above flux is not particularly limited.
  • Examples of the flux include zinc chloride, mixtures of zinc chloride and inorganic halides, mixtures of zinc chloride and inorganic acids, phosphoric acid, phosphoric acid derivatives, organic halides, hydrazine, amine compounds, molten salts, organic acids and pine resin and the like. Only one kind of the above flux may be used, or two or more kinds thereof may be used in combination.
  • amine compounds examples include cyclohexylamine, dicyclohexylamine, benzylamine, benzhydrylamine, imidazole, benzimidazole, phenylimidazole, carboxybenzimidazole, benzotriazole, carboxybenzotriazole, and the like.
  • Examples of the molten salt include ammonium chloride.
  • the flux is preferably an organic acid or rosin, more preferably rosin.
  • the above organic acid is preferably an organic acid having two or more carboxyl groups.
  • the organic acid having two or more carboxyl groups include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid.
  • the above pine resin is a rosin whose main component is abietic acid.
  • the rosins include abietic acid and acryl-modified rosins. From the standpoint of more effectively enhancing conduction reliability, the rosin is more preferably abietic acid.
  • the melting point (activation temperature) of the flux is preferably 10°C or higher, more preferably 50°C or higher, more preferably 70°C or higher, still more preferably 80°C or higher, and preferably 200°C or lower, more preferably 190°C. Below, it is more preferably 160° C. or lower, still more preferably 150° C. or lower, and even more preferably 140° C. or lower.
  • the melting point (activation temperature) of the flux is preferably 80° C. or higher and 190° C. or lower, and particularly preferably 80° C. or higher and 140° C. or lower.
  • Examples of the above-mentioned fluxes having a melting point (activation temperature) of 80° C. or more and 190° C. or less include succinic acid (melting point 186° C.), glutaric acid (melting point 96° C.), adipic acid (melting point 152° C.), pimelic acid (melting point 104° C.). °C), dicarboxylic acids such as suberic acid (melting point 142°C), benzoic acid (melting point 122°C), and malic acid (melting point 130°C).
  • the boiling point of the flux is preferably 300°C or lower.
  • the particle diameter of the flux-containing particles is preferably 100 nm or more, more preferably 200 nm or more, still more preferably 350 nm or more, and preferably 800 nm or less. , more preferably 500 nm or less, and still more preferably 400 nm or less.
  • the particle size of the flux-containing particles is the average particle size, and the average particle size indicates the volume average particle size.
  • the particle size of the flux-containing particles is determined using a particle size distribution analyzer or the like.
  • the ratio of the particle size of the conductive particles to the particle size of the flux-containing particles is preferably 3 or more, more preferably 6 or more, and still more preferably 16. or more, preferably 500 or less, more preferably 150 or less, even more preferably 100 or less, and particularly preferably 70 or less.
  • the ratio (particle diameter of the conductive particles/particle diameter of the flux-containing particles) is equal to or more than the lower limit and equal to or less than the upper limit, insulation reliability and conduction reliability are improved when the electrodes are electrically connected. can be enhanced more effectively.
  • the ratio of the particle diameter of the conductive particle main body to the particle diameter of the flux-containing particle is preferably 3 or more, more preferably 6 or more, and still more preferably. is 16 or more, preferably 500 or less, more preferably 150 or less, still more preferably 100 or less, and particularly preferably 60 or less.
  • the coefficient of variation (CV value) of the particle diameter of the flux-containing particles is preferably 20% or less.
  • the coefficient of variation (CV value) can be measured as follows.
  • CV value (%) ( ⁇ /Dn) ⁇ 100 ⁇ : standard deviation of particle size of flux-containing particles Dn: average value of particle size of flux-containing particles
  • the shape of the flux-containing particles is not particularly limited.
  • the flux-containing particles may have a spherical shape, a shape other than a spherical shape, or a flat shape. From the viewpoint of exhibiting the effects of the present invention more effectively, the flux-containing particles are preferably spherical.
  • the particle body of the flux-containing particles is a resin particle
  • the flux-containing particles preferably maintain their particulate form.
  • the flux-containing particles preferably do not have a breaking point in the compression-displacement curve when a maximum test load of 3.3 mN is applied to the flux-containing particles for 10 seconds.
  • the flux gradually leaks from the flux-containing particles due to heating and pressurization during conductive connection, so that the oxide film on the surface of the conductive particles and the surface of the electrode can be removed more effectively.
  • the reliability of conduction can be improved more effectively.
  • the flux-containing particles are compressed at 25° C. with a smooth indenter end face of a cylinder (diameter 50 ⁇ m, made of diamond) under the conditions of applying a maximum test load of 3.3 mN for 10 seconds. do.
  • the load value (N) and compression displacement (mm) at this time are measured to prepare a compression-displacement curve.
  • the microcompression tester for example, "ENT-NEXUS" manufactured by Elionix Co., Ltd. is used.
  • the flux-containing particles are preferably not microcapsules encapsulating flux.
  • the particle body in the flux-containing particles may be particles having a porous structure.
  • the porous structure means a structure having a plurality of pores (pores).
  • the distance from the surface of the flux-containing particles toward the center is divided into three equal parts, and the flux-containing particles are divided into three parts: a surface part, a center part, and an intermediate part between the surface part and the center part.
  • the flux-containing particles may contain the flux in the surface portion, the intermediate portion, or the central portion.
  • the flux-containing particles preferably contain flux in the surface portion, more preferably in the surface portion and the intermediate portion, and even more preferably in the surface portion, the intermediate portion, and the central portion. .
  • the flux gradually leaks from the flux-containing particles due to heating and pressurization during conductive connection, so that the oxide film on the surface of the conductive particles and the surface of the electrode can be removed more effectively.
  • the flux-containing particles may contain flux in the intermediate portion and the central portion.
  • the flux-containing particles preferably contain flux in the outermost surface portion having a thickness of 10 nm from the surface to the center of the flux-containing particles.
  • the residual rate of the flux-containing particles determined by the formula (1) is 99% or less.
  • Remaining rate of flux-containing particles (coverage rate of flux-containing particles after ultrasonic treatment/coverage rate of flux-containing particles before ultrasonic treatment) x 100... formula (1)
  • the coverage rate by the flux-containing particles means the total area of the portion where the flux-containing particles are arranged in 100% of the total surface area of the conductive particle body.
  • the coverage with the flux-containing particles is obtained by observing the conductive particles with an electron microscope or an optical microscope and calculating the percentage of the surface area of the portion where the flux-containing particles are arranged to the projected area of the main body of the conductive particles. Desired.
  • the coverage with the flux-containing particles is preferably determined by observing 20 arbitrary conductive particles with a scanning electron microscope (SEM), and measuring the surface area of the portion where the flux-containing particles are arranged, of the conductive particle body. It is obtained by calculating the average percentage of the projected area.
  • the residual rate of the flux-containing particles is preferably 90% or less, more preferably 70% or less, even more preferably 65% or less, and particularly preferably 60% or less.
  • the lower limit of the residual rate of the flux-containing particles is not particularly limited.
  • the residual rate of the flux-containing particles may be 0%.
  • Methods for adjusting the residual rate of the flux-containing particles to the preferred range include a method of using particles made of a material with low adhesiveness as the particle body of the flux-containing particles, and a method of using particles with a high flux content as flux-containing particles. A method of using it as a particle body of particles, and the like.
  • Examples of the method for incorporating the flux into the particle body include the following methods.
  • Examples of methods for disposing the flux-containing particles on the surface of the conductive particle body include chemical methods and physical or mechanical methods.
  • Examples of the chemical method include an interfacial polymerization method, a suspension polymerization method in the presence of particles, an emulsion polymerization method, and the like.
  • Examples of the physical or mechanical methods include spray drying, hybridization, electrostatic adhesion, atomization, dipping and vacuum deposition. From the viewpoint of more effectively improving the insulation reliability and conduction reliability when the electrodes are electrically connected, the method of arranging the flux-containing particles on the surface of the conductive particle body is an electrostatic Adhesive methods are preferred.
  • the outer surface of the conductive portion and the outer surface of the flux-containing particles may each be coated with a compound having a reactive functional group.
  • the outer surface of the conductive portion and the outer surface of the flux-containing particles may not be directly chemically bonded, but may be indirectly chemically bonded by a compound having a reactive functional group.
  • the carboxyl groups may be chemically bonded to the functional groups on the outer surface of the flux-containing particles via a polymer electrolyte such as polyethyleneimine.
  • the content of the flux-containing particles in 100% by weight of the conductive particles is preferably 1% by weight or more, more preferably 1.5% by weight or more. , more preferably 2% by weight or more, still more preferably 2.5% by weight or more, and particularly preferably 3% by weight or more.
  • the sum of the flux content in the flux-containing particles and the flux content in the flux film in 100% by weight of the conductive particles is preferably 1% by weight or more, more preferably 1.5% by weight or more, More preferably 2% by weight or more, more preferably 3% by weight or more, and particularly preferably 10% by weight or more.
  • the total flux content is at least the above lower limit, the effects of the present invention can be exhibited more effectively.
  • the flux content in the flux-containing particles is preferably 5 wt% or more, more preferably 100 wt% in total of the flux content in the flux-containing particles and the flux content in the flux film described later. It is 10% by weight or more, more preferably 15% by weight or more, still more preferably 20% by weight or more, and particularly preferably 50% by weight or more. When the flux content in the flux-containing particles is at least the above lower limit, the effects of the present invention can be exhibited more effectively.
  • the conductive particles comprise a flux film.
  • the flux film is arranged outside the conductive particle body.
  • the flux film is arranged outside the conductive portion.
  • the flux film is arranged on the surface of the conductive particle body.
  • the flux film is arranged on the surface of the conductive portion.
  • the flux film may be arranged outside the flux-containing particles, or may not be arranged outside the flux-containing particles.
  • the flux film may be arranged on the surfaces of the flux-containing particles, or may not be arranged on the surfaces of the flux-containing particles.
  • the flux in the flux film includes the above-mentioned flux.
  • the flux in the flux film may be the same as or different from the flux in the flux-containing particles.
  • the area of the flux film (coverage by the flux film) is preferably 40% or more, more preferably 50% or more.
  • the upper limit of the coverage rate is not particularly limited. The coverage may be 99% or less. When the coverage is the lower limit or more and the upper limit or less, the oxide film on the surface of the conductive particles and the surface of the electrode can be removed more effectively, and the electrodes are electrically connected. In this case, the conduction reliability can be enhanced more effectively.
  • the thickness of the flux film is preferably 0.5 nm or more, more preferably 1 nm or more, and preferably 100 nm or less, more preferably 50 nm or less, and even more preferably 25 nm or less.
  • the thickness of the flux film is equal to or more than the lower limit and equal to or less than the upper limit, the conduction reliability is more effectively improved, and the conductive particles do not become too hard, so that the electrodes can be electrically conductive at the time of connection. Particles can be sufficiently deformed.
  • a physical or mechanical method can be used as a method for arranging the flux film on the surface of the conductive particle body.
  • the physical or mechanical methods include spray drying, hybridization, electrostatic adhesion, atomization, dipping and vacuum deposition. From the viewpoint of more effectively improving the insulation reliability and conduction reliability when the electrodes are electrically connected, dipping is the method for disposing the flux film on the surface of the conductive particle body. is preferred.
  • the conductive material according to the present invention contains the conductive particles described above and a binder resin.
  • the conductive particles are preferably dispersed in a binder resin for use, and preferably dispersed in a binder resin for use as a conductive material.
  • the conductive material is preferably an anisotropic conductive material.
  • the conductive material is preferably used for electrical connection between electrodes.
  • the conductive material is preferably a conductive material for circuit connection. Since the above-described conductive particles are used in the conductive material, the reliability of insulation and reliability of conduction between electrodes can be further improved.
  • the binder resin is not particularly limited.
  • a known insulating resin is used as the binder resin.
  • the binder resin preferably contains a thermoplastic component (thermoplastic compound) or a curable component, and more preferably contains a curable component.
  • the curable component include photocurable components and thermosetting components.
  • the photocurable component preferably contains a photocurable compound and a photopolymerization initiator.
  • the thermosetting component preferably contains a thermosetting compound and a thermosetting agent.
  • binder resin examples include vinyl resins, thermoplastic resins, curable resins, thermoplastic block copolymers and elastomers. Only one kind of the binder resin may be used, or two or more kinds thereof may be used in combination.
  • Examples of the vinyl resin include vinyl acetate resin, acrylic resin and styrene resin.
  • examples of the thermoplastic resins include polyolefin resins, ethylene-vinyl acetate copolymers and polyamide resins.
  • examples of the curable resin include epoxy resin, urethane resin, polyimide resin and unsaturated polyester resin.
  • the curable resin may be a room temperature curable resin, a thermosetting resin, a photocurable resin, or a moisture curable resin.
  • the curable resin may be used in combination with a curing agent.
  • thermoplastic block copolymers examples include styrene-butadiene-styrene block copolymers, styrene-isoprene-styrene block copolymers, hydrogenated products of styrene-butadiene-styrene block copolymers, and styrene-isoprene. - hydrogenated products of styrene block copolymers;
  • the elastomer examples include styrene-butadiene copolymer rubber and acrylonitrile-styrene block copolymer rubber.
  • the conductive material includes, for example, a filler, an extender, a softener, a plasticizer, a polymerization catalyst, a curing catalyst, a coloring agent, an antioxidant, a heat stabilizer, and a light stabilizer. It may contain various additives such as agents, UV absorbers, lubricants, antistatic agents and flame retardants.
  • the method for dispersing the conductive particles in the binder resin is not particularly limited, and a conventionally known dispersing method can be used.
  • Examples of the method for dispersing the conductive particles in the binder resin include the following methods. A method of adding the conductive particles to the binder resin and then kneading and dispersing the mixture with a planetary mixer or the like. A method in which the conductive particles are uniformly dispersed in water or an organic solvent using a homogenizer or the like, then added to the binder resin, kneaded with a planetary mixer or the like, and dispersed. A method of diluting the binder resin with water, an organic solvent, or the like, adding the conductive particles, and kneading and dispersing the mixture with a planetary mixer or the like.
  • the viscosity ( ⁇ 25) of the conductive material at 25°C is preferably 30 Pa ⁇ s or more, more preferably 50 Pa ⁇ s or more, and preferably 400 Pa ⁇ s or less, more preferably 300 Pa ⁇ s or less.
  • the viscosity ( ⁇ 25) can be appropriately adjusted depending on the types and amounts of ingredients to be blended.
  • the viscosity ( ⁇ 25) can be measured, for example, using an E-type viscometer ("TVE22L” manufactured by Toki Sangyo Co., Ltd.) under conditions of 25°C and 5 rpm.
  • E-type viscometer (“TVE22L” manufactured by Toki Sangyo Co., Ltd.) under conditions of 25°C and 5 rpm.
  • the conductive material according to the present invention can be used as a conductive paste, a conductive film, and the like.
  • the conductive material according to the present invention is a conductive film
  • a film containing no conductive particles may be laminated on a conductive film containing conductive particles.
  • the conductive paste is preferably an anisotropic conductive paste.
  • the conductive film is preferably an anisotropic conductive film.
  • the content of the binder resin in 100% by weight of the conductive material is preferably 10% by weight or more, more preferably 30% by weight or more, still more preferably 50% by weight or more, and particularly preferably 70% by weight or more. is 99.99% by weight or less, more preferably 99.9% by weight or less.
  • the content of the binder resin is the lower limit or more and the upper limit or less, the conductive particles are efficiently arranged between the electrodes, and the connection reliability of the connection target members connected by the conductive material is further improved. can be done.
  • the content of the conductive particles in 100% by weight of the conductive material is preferably 0.01% by weight or more, more preferably 0.1% by weight or more, and preferably 80% by weight or less, more preferably 60% by weight. %, more preferably 40% by weight or less, particularly preferably 20% by weight or less, and most preferably 10% by weight or less.
  • the content of the conductive particles is equal to or more than the lower limit and equal to or less than the upper limit, reliability of electrical connection and reliability of insulation between electrodes can be further enhanced.
  • connection structure includes a first connection object member having a first electrode on the surface, a second connection object member having a second electrode on the surface, the first connection object member, and a connecting portion connecting the second connection target member.
  • the material of the connecting portion contains the above-described conductive particles.
  • the first electrode and the second electrode are electrically connected by the conductive particle body.
  • the material of the connecting portion is preferably conductive particles or a conductive material containing the conductive particles and a binder resin.
  • the connection structure includes a step of disposing the conductive particles or the conductive material between the first member to be connected and the second member to be connected, and a step of electrically connecting by thermocompression bonding.
  • the flux-containing particles are detached from the conductive particles during the thermocompression bonding.
  • the flux-containing particles between the conductive particle body and the electrode are detached from the conductive particles.
  • FIG. 5 is a cross-sectional view schematically showing a connection structure using conductive particles according to the first embodiment of the present invention.
  • a connection structure 81 shown in FIG. 5 includes a first connection target member 82, a second connection target member 83, and a connection portion that connects the first connection target member 82 and the second connection target member 83. 84.
  • the connecting portion 84 is made of a conductive material containing the conductive particles 1 .
  • the connecting portion 84 is preferably formed by curing a conductive material containing a plurality of conductive particles 1 .
  • the conductive particles 1 are schematically shown for convenience of illustration. Instead of the conductive particles 1, conductive particles 1A, conductive particles 1B, or conductive particles 1C 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 surface (lower surface).
  • the first electrode 82a and the second electrode 83a are electrically connected by the conductive particle body 11 of the one or more conductive particles 1 . Therefore, the first connection object member 82 and the second connection object member 83 are electrically connected by the conductive particle body 11 of the conductive particle 1 .
  • the manufacturing method of the connection structure is not particularly limited.
  • the conductive material is arranged between a first member to be connected and a second member to be connected to obtain a laminate, and then the laminate is heated and pressurized. methods and the like.
  • the pressure of the thermocompression bonding is preferably 40 MPa or higher, more preferably 60 MPa or higher, and preferably 90 MPa or lower, more preferably 70 MPa or lower.
  • the heating temperature for the thermocompression bonding is preferably 80° C. or higher, more preferably 100° C. or higher, and preferably 140° C. or lower, more preferably 120° C. or lower.
  • the flux-containing particles and the flux film can be easily removed from the surface of the conductive particles at the time of conductive connection. can further improve the reliability of electrical continuity.
  • the flux gradually leaks from the flux-containing particles when the flux-containing particles are desorbed, the oxide film on the surface of the conductive particles and the surface of the electrode can be removed more effectively.
  • the electrodes are electrically connected, the reliability of conduction can be improved more effectively.
  • the oxide film on the surfaces of the conductive particles and the electrodes after the conductive connection can be effectively removed, and the electrodes are separated.
  • the conduction reliability can be enhanced more effectively.
  • the flux-containing particles and the flux film existing between the conductive particles and the first electrode and the second electrode can be eliminated.
  • the flux-containing particles and the flux film existing between the conductive particles and the first electrode and the second electrode become conductive. It desorbs from the surface of the particle.
  • part of the flux-containing particles and the flux film are detached from the surfaces of the conductive particles, and the surfaces (conductive portions) of the conductive particles are partially exposed. I have something to do.
  • the portion where the surface (conductive portion) of the conductive particle body is exposed contacts the first electrode and the second electrode, so that the first electrode and the second electrode are connected via the conductive particle body.
  • the electrodes can be electrically connected.
  • the first member to be connected and the second member to be connected are not particularly limited.
  • the first connection target member and the second connection target member include electronic components such as semiconductor chips, semiconductor packages, LED chips, LED packages, capacitors and diodes, as well as resin films, printed circuit boards, flexible Examples include electronic components such as circuit boards such as printed boards, flexible flat cables, rigid flexible boards, glass epoxy boards and glass boards.
  • the first member to be connected and the second member to be connected are preferably electronic components.
  • the electrodes provided on the connection target members include metal electrodes such as gold electrodes, nickel electrodes, tin electrodes, aluminum electrodes, copper electrodes, molybdenum electrodes, silver electrodes, SUS electrodes, and tungsten electrodes.
  • the electrode is preferably a gold electrode, a nickel electrode, a tin electrode, a silver electrode or a copper electrode.
  • the electrode is preferably an aluminum electrode, a copper electrode, a molybdenum electrode, a silver electrode, or a tungsten electrode.
  • the electrode When the electrode is an aluminum electrode, it may be an electrode made of only aluminum, or an electrode in which an aluminum layer is laminated on the surface of a metal oxide layer.
  • materials for the metal oxide layer include indium oxide doped with a trivalent metal element and zinc oxide doped with a trivalent metal element.
  • the trivalent metal elements include Sn, Al and Ga.
  • Rosin-based flux ("KR-612" manufactured by Arakawa Chemical Industries, softening point: 82 ° C.)
  • Adipate benzylamine salt (melting point: 171°C)
  • Example 1 Production of conductive particle body (production of substrate particles) Resin particles (average particle diameter: 20 ⁇ m) formed from a copolymer of tetramethylolmethane tetraacrylate and divinylbenzene were prepared as substrate particles. After dispersing 10 parts by weight of the base particles in 100 parts by weight of an alkaline solution containing 5% by weight of the palladium catalyst solution using an ultrasonic disperser, the solution was filtered to obtain the base particles. Next, the substrate particles were added to 100 parts by weight of a solution containing 1% by weight of dimethylamine borane to activate the surfaces of the substrate particles.
  • a dispersion liquid (A) After thoroughly washing the surface-activated substrate particles with water, they were added to 500 parts by weight of distilled water and dispersed to obtain a dispersion liquid (A). Next, 1 g of a nickel particle slurry (average particle size: 100 nm) was added to the dispersion (A) over 3 minutes to obtain a suspension (A) containing substrate particles to which the core substance was attached.
  • a nickel plating solution (pH 8.5) containing 0.35 mol/L nickel sulfate, 1.38 mol/L dimethylamine borane, and 0.5 mol/L sodium citrate was prepared. While the suspension (A) was stirred at 70° C., the nickel plating solution was gradually dropped into the suspension (A) to perform electroless nickel plating. After that, the particles were taken out by filtration, washed with water, and dried to form a first conductive portion (nickel-boron layer) on the surface of the substrate particles.
  • a tin plating solution was prepared by adjusting a mixed solution containing 15 g/L of tin sulfate, 45 g/L of ethylenediaminetetraacetic acid, and 1.5 g/L of phosphinic acid to pH 8.5 with sodium hydroxide.
  • a reducing solution was prepared by adjusting the pH of a solution containing 5 g/L of sodium borohydride to 10.0 with sodium hydroxide. The tin plating solution was gradually dripped onto the substrate particles having the first conductive portions to carry out electroless tin plating, and then reduced with a reducing solution.
  • the above composition contains 1080 mmol of methyl methacrylate, 10 mmol of ethylene glycol dimethacrylate, 0.5 mmol of 4-(methacryloyloxy)phenyldimethylsulfonium methylsulfate, and 2,2′-azobis ⁇ 2-[N-(2-carboxy ethyl)amidino]propane ⁇ 0.5 mmol.
  • the reaction mixture was lyophilized to obtain resin particles (particle size: 360 nm) having sulfone groups derived from 4-(methacryloyloxy)phenyldimethylsulfonium methylsulfate on their surfaces.
  • the dispersion liquid (C) was mixed with 300 mL of ethanol in which 0.5 g of a rosin-based flux was dissolved, and the mixture was stirred for 10 minutes by ultrasonic dispersion at a temperature of 50°C. After filtration through a 3 ⁇ m mesh filter, the particles were dried to obtain conductive particles having flux-containing particles and a flux film.
  • conductive material anisotropic conductive paste 7 parts by weight of the obtained conductive particles, 25 parts by weight of bisphenol A type phenoxy resin, 4 parts by weight of fluorene type epoxy resin, and 30 parts by weight of phenol novolak type epoxy resin.
  • a conductive material anisotropic conductive paste was obtained by blending parts by weight and SI-60L (manufactured by Sanshin Chemical Industry Co., Ltd.), followed by defoaming and stirring for 3 minutes.
  • a flexible printed circuit board was prepared on which an Au electrode pattern (first electrode, electrode: Ni/Au thin film on Cu) with L/S of 200 ⁇ m/200 ⁇ m was formed on the upper surface.
  • a printed circuit board having an Au electrode pattern (second electrode, electrode: Ni/Au thin film on Cu) with L/S of 200 ⁇ m/200 ⁇ m formed on the lower surface was prepared.
  • the obtained anisotropic conductive paste was applied onto the printed circuit board so as to have a thickness of 30 ⁇ m to form an anisotropic conductive paste layer.
  • the flexible printed circuit board was laminated on the anisotropic conductive paste layer so that the electrodes faced each other. After that, while adjusting the temperature of the head so that the temperature of the anisotropic conductive paste layer becomes 100° C., a pressure heating head is placed on the upper surface of the semiconductor chip, and a pressure of 60 MPa is applied to the anisotropic conductive paste layer. It was cured at 100° C. to obtain a connected structure.
  • Example 2 When producing the particle bodies of the flux-containing particles, the amount of methyl methacrylate in the composition was changed from 1080 mmol to 180 mmol, and 900 mmol of glycidyl methacrylate was added to the composition.
  • Conductive particles, a conductive material and a connection structure were obtained in the same manner as in Example 1 except for the above changes.
  • Example 3 During the preparation of the particle body in the flux-containing particles, 840 mmol of polystyrene and 240 mmol of lauryl methacrylate were added to the composition instead of 1080 mmol of methyl methacrylate. Conductive particles, a conductive material and a connection structure were obtained in the same manner as in Example 1 except for the above changes.
  • Example 4 When producing the particle bodies of the flux-containing particles, the blending amount of methyl methacrylate in the composition was changed from 1080 mmol to 540 mmol, and 540 mmol of glycidyl methacrylate was added to the composition. Conductive particles, a conductive material and a connection structure were obtained in the same manner as in Example 1 except for the above changes.
  • Example 5 Conductive particles, a conductive material, and a connection structure were obtained in the same manner as in Example 1, except that the flux in the flux-containing particles and flux film was changed to benzylamine adipate.
  • Example 6 When forming the first conductive portion, instead of the nickel plating solution, a mixed solution of 200 g/L of copper sulfate, 150 g/L of ethylenediaminetetraacetic acid, 100 g/L of sodium gluconate, and 50 g/L of formaldehyde was used. A copper plating solution adjusted to pH 10.5 with ammonia was prepared. While the suspension (A) was stirred at 65° C., 250 ml of the copper plating solution was dropped into the suspension (A) at 10 ml/min to perform electroless copper plating. After that, the particles are taken out by filtration, washed with water, dried, and the first conductive portion is formed on the surface of the substrate particles. (copper layer, thickness 0.2 ⁇ m) was formed. A conductive particle, a conductive material, and a connection structure were obtained in the same manner as in Example 1, except that the first conductive portion was a copper layer.
  • Example 7 Example 1 except that no core substance was used and no projections were formed in the preparation of the conductive particle body, and only a tin layer (0.3 ⁇ m) was formed in the formation of the conductive portion. Conductive particles, a conductive material and a connection structure were obtained in the same manner.
  • Example 8 A conductive particle, a conductive material, and a connection structure were obtained in the same manner as in Example 1, except that only a nickel layer (0.3 ⁇ m) was formed as the conductive portion in the preparation of the conductive particle body.
  • Example 9 The substrate particles having the first conductive portion (nickel-boron layer) obtained in Example 1 were added to 100 parts by weight of distilled water and dispersed to obtain a suspension. After that, a reducing gold plating solution containing 0.03 mol/L of gold cyanide and 0.1 mol/L of hydroquinone as a reducing agent was prepared instead of the tin plating solution when forming the second conductive portion. While stirring the resulting suspension at 70° C., the reduction gold plating solution was gradually dropped into the suspension to perform reduction gold plating.
  • Example 2 After that, by filtering the suspension, the particles are taken out, washed with water, and dried to form the first conductive portion (nickel-boron layer, thickness 0.2 ⁇ m) and the second conductive portion (gold layer, thickness 0.2 ⁇ m). .25 ⁇ m) was obtained.
  • a conductive particle, a conductive material, and a connection structure were obtained in the same manner as in Example 1, except that the obtained conductive particle body was used.
  • the ratio of the particle size of the conductive particles to the particle size of the flux-containing particles was calculated.
  • Connection resistance is 0.32 ⁇ or less ⁇ : Connection resistance is over 0.32 ⁇ and 0.35 ⁇ or less ⁇ : Connection resistance is over 0.35 ⁇ and 0.41 ⁇ or less ⁇ : Connection resistance is 0 over .41 ⁇

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Abstract

Provided are conductive particles which enable effective removal of oxide films on the surfaces of the conductive particles and the surfaces of electrodes and effective improvement in conduction reliability at the time of electrical connection between the electrodes.　Conductive particles according to the present invention each comprise: a conductive particle body; a plurality of flux-containing particles; and a flux film. The conductive particle body includes a base material particle, and a conductive part disposed outside the base material particle. The flux-containing particles are arranged outside the conductive particle body, and the flux film is disposed outside the conductive particle body.

Description

導電性粒子、導電材料及び接続構造体Conductive particles, conductive materials and connecting structures
　本発明は、フラックスを用いた導電性粒子に関する。また、本発明は、上記導電性粒子を用いた導電材料及び接続構造体に関する。 The present invention relates to conductive particles using flux. The present invention also relates to a conductive material and a connection structure using the conductive particles.
　異方性導電ペースト及び異方性導電フィルム等の異方性導電材料が広く知られている。該異方性導電材料では、バインダー樹脂中に導電性粒子が分散されている。 Anisotropic conductive materials such as anisotropic conductive paste and anisotropic conductive film are widely known. In the anisotropic conductive material, conductive particles are dispersed in a binder resin.
　上記異方性導電材料は、各種の接続構造体を得るために用いられている。上記異方性導電材料を用いる接続としては、例えば、フレキシブルプリント基板とガラス基板との接続（ＦＯＧ（Ｆｉｌｍ　ｏｎ　Ｇｌａｓｓ））、半導体チップとフレキシブルプリント基板との接続（ＣＯＦ（Ｃｈｉｐ　ｏｎ　Ｆｉｌｍ））、半導体チップとガラス基板との接続（ＣＯＧ（Ｃｈｉｐ　ｏｎ　Ｇｌａｓｓ））、並びにフレキシブルプリント基板とガラスエポキシ基板との接続（ＦＯＢ（Ｆｉｌｍ　ｏｎ　Ｂｏａｒｄ））等が挙げられる。 The anisotropic conductive material is used to obtain various connection structures. Examples of the connection using the anisotropic conductive material include connection between a flexible printed circuit board and a glass substrate (FOG (Film on Glass)), connection between a semiconductor chip and a flexible printed circuit board (COF (Chip on Film)), Examples include connection between a semiconductor chip and a glass substrate (COG (Chip on Glass)) and connection between a flexible printed circuit board and a glass epoxy substrate (FOB (Film on Board)).
　上記異方性導電材料により、例えば、フレキシブルプリント基板の電極とガラスエポキシ基板の電極とを電気的に接続する際には、ガラスエポキシ基板上に、導電性粒子を含む異方性導電材料を配置する。次に、フレキシブルプリント基板を積層して、加熱及び加圧する。これにより、異方性導電材料を硬化させて、導電性粒子を介して電極間を電気的に接続して、接続構造体を得る。 For example, when electrically connecting an electrode of a flexible printed circuit board and an electrode of a glass epoxy board using the anisotropic conductive material, an anisotropic conductive material containing conductive particles is placed on the glass epoxy board. do. Next, the flexible printed circuit board is laminated and heated and pressurized. As a result, the anisotropic conductive material is cured and the electrodes are electrically connected via the conductive particles to obtain a connection structure.
　上記導電性粒子及び上記異方性導電材料では、導電接続前の保管条件等により、導電性粒子の導電部の表面に酸化被膜が形成されることがある。また、導電接続される電極の表面にも酸化被膜が形成されることがある。この酸化被膜の存在は、導電接続された接続構造体において、接続抵抗が高くなり、導通信頼性が低下する原因になる。導電性粒子及び電極の表面の酸化被膜を除去するために、異方性導電材料にフラックスを配合したり、導電性粒子の表面にフラックスを配置したりすることがある。 With the conductive particles and the anisotropic conductive material, an oxide film may be formed on the surface of the conductive portion of the conductive particles depending on storage conditions before conductive connection. Also, an oxide film may be formed on the surface of the electrodes to be electrically connected. The presence of this oxide film causes an increase in connection resistance and a decrease in conduction reliability in a connection structure that is electrically connected. In order to remove the oxide film on the surfaces of the conductive particles and the electrodes, flux may be added to the anisotropic conductive material or placed on the surfaces of the conductive particles.
　下記の特許文献１には、（Ａ）融点が２２０℃以下である金属を含む導電性粒子、（Ｂ）熱硬化性樹脂、及び（Ｃ）フラックス活性剤を含む導電性接着剤組成物が開示されている。（Ｃ）フラックス活性剤の平均粒子径は１５μｍ以下である。 Patent Document 1 below discloses a conductive adhesive composition containing (A) conductive particles containing a metal having a melting point of 220° C. or lower, (B) a thermosetting resin, and (C) a flux activator. It is (C) The flux activator has an average particle size of 15 μm or less.
　下記の特許文献２には、絶縁フィルム内に金属粒子を備えた異方性導電フィルムが開示されている。該異方性導電フィルムでは、平面視において金属粒子が規則配列されており、金属粒子の異方性導電フィルム表面側端部又は異方性導電フィルム裏面側端部の少なくともいずれか一方の端部にフラックスが接触もしくは近接するように配置されている。特許文献２の金属粒子では、金属粒子の端部においてフラックスが接触または近接している。 Patent Document 2 below discloses an anisotropic conductive film having metal particles in an insulating film. In the anisotropic conductive film, the metal particles are regularly arranged in plan view, and at least one end of the metal particles on the front side of the anisotropic conductive film or the back side of the anisotropic conductive film is arranged so that the flux is in contact with or close to In the metal particles of Patent Document 2, the flux is in contact with or close to the ends of the metal particles.
ＷＯ２０１２／１０２０７７Ａ１WO2012/102077A1 ＷＯ２０１６／１１４１６０Ａ１WO2016/114160A1
　導電性粒子を含む導電材料を用いて導電接続を行う際には、上方の複数の電極と下方の複数の電極とが電気的に接続されて、導電接続が行われる。導電性粒子は、上下の電極間に配置されることが望ましく、隣接する横方向の電極間には配置されないことが望ましい。隣接する横方向の電極間は、電気的に接続されないことが望ましい。 When conducting a conductive connection using a conductive material containing conductive particles, a plurality of upper electrodes and a plurality of lower electrodes are electrically connected to form a conductive connection. The conductive particles are preferably located between the top and bottom electrodes and not between adjacent lateral electrodes. It is desirable that there is no electrical connection between adjacent lateral electrodes.
　特許文献１，２に記載のような従来の導電材料では、導電接続時の加熱及び加圧等により、フラックスの全体が速やかに導電性粒子又は電極の表面にて活性化し、フラックスの活性能が早期に失われやすい。このため、導電性粒子の表面の酸化被膜を十分に除去することができないことがある。結果として、接続されるべき上下の電極間の接続抵抗が高くなり、導通信頼性が低下することがある。 In conventional conductive materials such as those described in Patent Documents 1 and 2, the flux as a whole is rapidly activated on the surface of the conductive particles or electrodes by heating and pressurization during conductive connection, and the activating ability of the flux is enhanced. prone to early loss. For this reason, it may not be possible to sufficiently remove the oxide film on the surface of the conductive particles. As a result, the connection resistance between the upper and lower electrodes to be connected increases, and the reliability of conduction may decrease.
　本発明の目的は、導電性粒子の表面及び電極の表面の酸化被膜を効果的に除去することができ、かつ、電極間を電気的に接続した場合に、導通信頼性を効果的に高めることができる、導電性粒子を提供することである。また、本発明の目的は、上記導電性粒子を用いた導電材料及び接続構造体を提供することである。 An object of the present invention is to effectively remove the oxide film on the surface of the conductive particles and the surface of the electrodes, and to effectively increase the reliability of conduction when the electrodes are electrically connected. An object of the present invention is to provide conductive particles capable of Another object of the present invention is to provide a conductive material and a connection structure using the conductive particles.
　本発明の広い局面によれば、導電性粒子本体と、複数のフラックス含有粒子と、フラックス膜とを備え、前記導電性粒子本体が、基材粒子と、前記基材粒子の外側に配置された導電部とを備え、前記フラックス含有粒子が、前記導電性粒子本体の外側に配置されており、前記フラックス膜が、前記導電性粒子本体の外側に配置されている、導電性粒子が提供される。 According to a broad aspect of the present invention, a conductive particle body, a plurality of flux-containing particles, and a flux film are provided, and the conductive particle body is disposed outside the substrate particles and the substrate particles. and a conductive portion, wherein the flux-containing particles are arranged outside the conductive particle body, and the flux film is arranged outside the conductive particle body. .
　本発明に係る導電性粒子のある特定の局面では、前記フラックス含有粒子が、粒子本体と、フラックスとを含み、前記粒子本体が、樹脂粒子である。 In a specific aspect of the conductive particles according to the present invention, the flux-containing particles contain particle bodies and flux, and the particle bodies are resin particles.
　本発明に係る導電性粒子のある特定の局面では、前記樹脂粒子の材料が、重合性単量体を含み、前記重合性単量体の単独重合体のガラス転移温度が、８０℃以上である。 In a specific aspect of the conductive particles according to the present invention, the material of the resin particles contains a polymerizable monomer, and the homopolymer of the polymerizable monomer has a glass transition temperature of 80° C. or higher. .
　本発明に係る導電性粒子のある特定の局面では、前記フラックス含有粒子が、前記フラックス含有粒子に最大試験荷重３．３ｍＮを１０秒かけて負荷したときの圧縮－変位曲線において、破壊点を有しない。 In a specific aspect of the conductive particles according to the present invention, the flux-containing particles have a breaking point in the compression-displacement curve when a maximum test load of 3.3 mN is applied to the flux-containing particles for 10 seconds. do not do.
　本発明に係る導電性粒子のある特定の局面では、前記導電部が、錫を含む。 In a specific aspect of the conductive particles according to the present invention, the conductive portion contains tin.
　本発明に係る導電性粒子のある特定の局面では、前記導電性粒子の粒子径の、前記フラックス含有粒子の粒子径に対する比が、３以上５００以下である。 In a specific aspect of the conductive particles according to the present invention, the ratio of the particle size of the conductive particles to the particle size of the flux-containing particles is 3 or more and 500 or less.
　本発明に係る導電性粒子のある特定の局面では、前記導電性粒子の粒子径が、１μｍ以上５０μｍ以下である。 In a specific aspect of the conductive particles according to the present invention, the conductive particles have a particle diameter of 1 μm or more and 50 μm or less.
　本発明に係る導電性粒子のある特定の局面では、エタノール１００重量部に、前記導電性粒子３重量部を添加した導電性粒子含有液を２０℃及び４０ｋＨｚの条件で５分間超音波処理したときに、下記式（１）により求められるフラックス含有粒子の残存率が９９％以下である。 In a specific aspect of the conductive particles according to the present invention, when a conductive particle-containing liquid obtained by adding 3 parts by weight of the conductive particles to 100 parts by weight of ethanol is subjected to ultrasonic treatment for 5 minutes at 20 ° C. and 40 kHz In addition, the residual rate of flux-containing particles determined by the following formula (1) is 99% or less.
　フラックス含有粒子の残存率（％）＝（超音波処理後のフラックス含有粒子による被覆率／超音波処理前のフラックス含有粒子による被覆率）×１００・・・式（１） Remaining rate of flux-containing particles (%) = (coverage rate of flux-containing particles after ultrasonic treatment/coverage rate of flux-containing particles before ultrasonic treatment) x 100... formula (1)
　本発明の広い局面によれば、上述した導電性粒子と、バインダー樹脂とを含む、導電材料が提供される。 A broad aspect of the present invention provides a conductive material containing the above-described conductive particles and a binder resin.
　本発明の広い局面によれば、第１の電極を表面に有する第１の接続対象部材と、第２の電極を表面に有する第２の接続対象部材と、前記第１の接続対象部材と、前記第２の接続対象部材を接続している接続部とを備え、前記接続部の材料が、上述した導電性粒子を含み、前記第１の電極と前記第２の電極とが、前記導電性粒子本体により電気的に接続されている、接続構造体が提供される。 According to a broad aspect of the present invention, a first member to be connected having a first electrode on its surface, a second member to be connected having a second electrode on its surface, the first member to be connected, a connecting portion connecting the second member to be connected, wherein the material of the connecting portion contains the conductive particles described above, and the first electrode and the second electrode are electrically conductive. A connection structure is provided that is electrically connected by the particle bodies.
　本発明に係る導電性粒子は、導電性粒子本体と、複数のフラックス含有粒子と、フラックス膜とを備える。本発明に係る導電性粒子では、上記導電性粒子本体が、基材粒子と、上記基材粒子の外側に配置された導電部とを備える。本発明に係る導電性粒子では、上記フラックス含有粒子が、上記導電性粒子本体の外側に配置されており、上記フラックス膜が、上記導電性粒子本体の外側に配置されている。本発明に係る導電性粒子では、上記の構成が備えられているので、導電性粒子の表面及び電極の表面の酸化被膜を効果的に除去することができ、かつ、電極間を電気的に接続した場合に、導通信頼性を効果的に高めることができる。 A conductive particle according to the present invention comprises a conductive particle body, a plurality of flux-containing particles, and a flux film. In the conductive particle according to the present invention, the conductive particle main body includes a substrate particle and a conductive portion arranged outside the substrate particle. In the conductive particles according to the present invention, the flux-containing particles are arranged outside the conductive particle body, and the flux film is arranged outside the conductive particle body. Since the conductive particles according to the present invention have the above configuration, the oxide film on the surfaces of the conductive particles and the electrodes can be effectively removed, and the electrodes are electrically connected. In this case, the conduction reliability can be effectively improved.
図１は、本発明の第１の実施形態に係る導電性粒子を示す断面図である。FIG. 1 is a cross-sectional view showing conductive particles according to a first embodiment of the present invention. 図２は、本発明の第２の実施形態に係る導電性粒子を示す断面図である。FIG. 2 is a cross-sectional view showing conductive particles according to a second embodiment of the present invention. 図３は、本発明の第３の実施形態に係る導電性粒子を示す断面図である。FIG. 3 is a cross-sectional view showing conductive particles according to a third embodiment of the present invention. 図４は、本発明の第４の実施形態に係る導電性粒子を示す断面図である。FIG. 4 is a cross-sectional view showing conductive particles according to a fourth embodiment of the present invention. 図５は、本発明の第１の実施形態に係る導電性粒子を用いた接続構造体を模式的に示す断面図である。FIG. 5 is a cross-sectional view schematically showing a connected structure using conductive particles according to the first embodiment of the present invention.
　以下、本発明の詳細を説明する。 The details of the present invention will be described below.
　（導電性粒子）
　本発明に係る導電性粒子は、導電性粒子本体と、複数のフラックス含有粒子と、フラックス膜とを備える。本発明に係る導電性粒子では、上記導電性粒子本体が、基材粒子と、上記基材粒子の外側に配置された導電部とを備える。本発明に係る導電性粒子では、上記フラックス含有粒子が、上記導電性粒子本体の外側に配置されており、上記フラックス膜が、上記導電性粒子本体の外側に配置されている。 (Conductive particles)
A conductive particle according to the present invention includes a conductive particle body, a plurality of flux-containing particles, and a flux film. In the conductive particle according to the present invention, the conductive particle main body includes a substrate particle and a conductive portion arranged outside the substrate particle. In the conductive particles according to the present invention, the flux-containing particles are arranged outside the conductive particle body, and the flux film is arranged outside the conductive particle body.
　本発明に係る導電性粒子では、上記の構成が備えられているので、導電性粒子の表面（具体的には、導電性粒子の導電部の表面）及び電極の表面の酸化被膜を効果的に除去することができ、かつ、電極間を電気的に接続した場合に、導通信頼性を効果的に高めることができる。 Since the conductive particles according to the present invention have the above configuration, the surface of the conductive particles (specifically, the surface of the conductive portion of the conductive particles) and the oxide film on the surface of the electrode are effectively removed. When it can be removed and the electrodes are electrically connected, the reliability of conduction can be effectively improved.
　従来の導電性粒子及び導電材料では、導電接続時の加熱及び加圧等によりフラックス成分の全体が速やかに導電性粒子又は電極の表面にて活性化し、フラックスの活性能が早期に失われやすい。このため、導電性粒子の表面の酸化被膜を十分に除去することができないことがある。結果として、接続されるべき上下の電極間の接続抵抗が高くなり、導通信頼性が低下することがある。 With conventional conductive particles and conductive materials, the entire flux component is quickly activated on the surface of the conductive particles or electrodes due to heating and pressurization during conductive connection, and the flux tends to lose its activating ability early. For this reason, it may not be possible to sufficiently remove the oxide film on the surface of the conductive particles. As a result, the connection resistance between the upper and lower electrodes to be connected increases, and the reliability of conduction may decrease.
　本発明者は、鋭意検討の結果、特定の構成を備える導電性粒子を用いることで、上記の課題を解決できることを見出した。本発明に係る導電性粒子では、導電接続時の初期段階で、導電接続時の加熱及び加圧等により、フラックス膜によって、導電性粒子の表面及び電極の表面の酸化被膜を効果的に除去することができる。さらに、本発明に係る導電性粒子では、導電接続時の加熱及び加圧等により、フラックス含有粒子からフラックスが徐々に漏出するので、導電性粒子の表面及び電極の表面の酸化被膜を効果的に除去することができる。また、本発明では、導電接続後にも、フラックス含有粒子からフラックスが徐々に漏出するので、導電性粒子の表面及び電極の表面の酸化被膜を除去することができる。結果として、接続されるべき上下の電極間の導通信頼性を効果的に高めることができる。 As a result of intensive studies, the inventor found that the above problems can be solved by using conductive particles having a specific configuration. In the conductive particles according to the present invention, the oxide film on the surface of the conductive particles and the surface of the electrode is effectively removed by the flux film in the initial stage of conductive connection by heating and pressurizing at the time of conductive connection. be able to. Furthermore, in the conductive particles according to the present invention, the flux gradually leaks from the flux-containing particles due to heating and pressurization at the time of conductive connection. can be removed. In addition, in the present invention, the flux gradually leaks from the flux-containing particles even after the conductive connection, so that the oxide film on the surface of the conductive particles and the surface of the electrode can be removed. As a result, it is possible to effectively improve the reliability of conduction between the upper and lower electrodes to be connected.
　また、本発明に係る導電性粒子では、導電接続時に、導電性粒子に縦方向の実装応力がかかることにより、導電性粒子本体の上部及び下部の表面からフラックス含有粒子が脱離しやすい。これにより、導電性粒子本体と電極との間に、フラックス含有粒子が残存しにくく、結果として、接続されるべき上下の電極間の導通信頼性を効果的に高めることができる。また、導電接続時に、導電性粒子に横方向の応力がかかりにくいため、導電性粒子本体の横方向の表面からフラックス含有粒子が脱離しがたい。結果として、本発明に係る導電性粒子では、接続されてはならない横方向に隣接する電極間の絶縁信頼性を効果的に高めることができる。 In addition, in the conductive particles according to the present invention, the flux-containing particles are easily detached from the upper and lower surfaces of the conductive particle body due to the vertical mounting stress applied to the conductive particles during conductive connection. This makes it difficult for the flux-containing particles to remain between the conductive particle body and the electrode, and as a result, it is possible to effectively improve the reliability of conduction between the upper and lower electrodes to be connected. In addition, since stress in the horizontal direction is less likely to be applied to the conductive particles at the time of conductive connection, the flux-containing particles are less likely to detach from the surfaces in the horizontal direction of the main body of the conductive particles. As a result, the conductive particles according to the present invention can effectively improve the insulation reliability between laterally adjacent electrodes that should not be connected.
　したがって、本発明では、電極間を電気的に接続した場合に、導通信頼性及び絶縁信頼性を効果的に高めることができる。 Therefore, in the present invention, it is possible to effectively improve conduction reliability and insulation reliability when the electrodes are electrically connected.
　さらに、本発明では、上記の構成が備えられているので、従来の導電性粒子及び導電材料に比べて、フラックスの含有量を低減することができる。本発明では、少量のフラックスで、導電性粒子の表面及び電極の表面の酸化被膜を効果的に除去することができ、かつ、電極間を電気的に接続した場合に、導通信頼性を効果的に高めることができる。 Furthermore, since the present invention has the above configuration, it is possible to reduce the flux content compared to conventional conductive particles and conductive materials. In the present invention, with a small amount of flux, the oxide film on the surface of the conductive particles and the surface of the electrode can be effectively removed, and when the electrodes are electrically connected, the conduction reliability is effectively improved. can be increased to
　上記導電性粒子は、バインダー樹脂中に分散され、導電材料を得るために好適に用いられる。 The conductive particles are dispersed in a binder resin and are suitably used to obtain a conductive material.
　以下、図面を参照しつつ、本発明の具体的な実施形態を説明する。なお、図１及び後述する図において、異なる箇所は互いに置き換え可能である。また、図１及び後述する図において、図示の便宜上、各構成要素の大きさ及び厚みは、実際の大きさ及び厚みと異なる場合がある。例えば、フラックス膜の厚みは、かなり薄い場合がある。 Specific embodiments of the present invention will be described below with reference to the drawings. In addition, in FIG. 1 and the figures described later, different parts can be replaced with each other. In addition, in FIG. 1 and the figures described later, for convenience of illustration, the size and thickness of each component may differ from the actual size and thickness. For example, the thickness of the flux film may be fairly thin.
　図１は、本発明の第１の実施形態に係る導電性粒子を示す断面図である。 FIG. 1 is a cross-sectional view showing conductive particles according to the first embodiment of the present invention.
　図１に示す導電性粒子１は、導電性粒子本体１１と、複数のフラックス含有粒子１２と、フラックス膜１３とを備える。導電性粒子１では、導電性粒子本体１１が、基材粒子２１と、基材粒子２１の外側に配置された導電部２２とを備える。導電性粒子１では、フラックス含有粒子１２が、導電性粒子本体１１の外側に配置されている。導電性粒子１では、フラックス膜１３が、導電性粒子本体１１の外側に配置されている。導電部２２は、基材粒子２１の表面上に配置されており、基材粒子２１に接している。導電性粒子１では、フラックス含有粒子１２が、導電性粒子本体１１（導電部２２）の表面上に配置されており、導電性粒子本体１１（導電部２２）と接している。導電性粒子１では、フラックス膜１３が、導電性粒子本体１１（導電部２２）の表面上に配置されており、導電性粒子本体１１（導電部２２）と接している。 The conductive particle 1 shown in FIG. 1 includes a conductive particle body 11, a plurality of flux-containing particles 12, and a flux film 13. In the conductive particle 1 , the conductive particle body 11 includes the base particle 21 and the conductive part 22 arranged outside the base particle 21 . In the conductive particles 1 , the flux-containing particles 12 are arranged outside the conductive particle body 11 . In the conductive particles 1 , the flux film 13 is arranged outside the conductive particle body 11 . The conductive portion 22 is arranged on the surface of the substrate particle 21 and is in contact with the substrate particle 21 . In the conductive particles 1, the flux-containing particles 12 are arranged on the surface of the conductive particle body 11 (conductive portion 22) and are in contact with the conductive particle body 11 (conductive portion 22). In the conductive particles 1, the flux film 13 is arranged on the surface of the conductive particle body 11 (conductive portion 22) and is in contact with the conductive particle body 11 (conductive portion 22).
　導電部２２は、基材粒子２１の表面を覆っている。導電性粒子本体１１は、基材粒子２１の表面が導電部２２により被覆された被覆粒子である。導電性粒子本体１１は、表面に導電部２２を有する。 The conductive portion 22 covers the surfaces of the base particles 21 . The conductive particle body 11 is a coated particle in which the surface of the base particle 21 is coated with the conductive part 22 . The conductive particle body 11 has a conductive portion 22 on its surface.
　導電性粒子１では、導電部２２は、導電層である。導電部２２は、単層の導電層である。上記導電性粒子では、上記導電部が上記基材粒子の表面の全体を覆っていてもよく、上記導電部が上記基材粒子の表面の一部を覆っていてもよい。 In the conductive particles 1, the conductive portion 22 is a conductive layer. The conductive portion 22 is a single-layer conductive layer. In the conductive particles, the conductive portion may cover the entire surface of the substrate particle, or the conductive portion may cover a portion of the surface of the substrate particle.
　導電性粒子１では、フラックス膜１３が、導電性粒子本体１１の表面（導電部２２の表面）と、フラックス含有粒子１２の表面とを覆っている。 In the conductive particles 1 , the flux film 13 covers the surface of the conductive particle body 11 (the surface of the conductive portion 22 ) and the surface of the flux-containing particles 12 .
　導電性粒子１は、例えば、フラックス膜１３を配置する前のフラックス含有粒子１２が付着した導電性粒子本体１１を用いて、フラックス処理によりフラックス膜１３を形成することで、得ることができる。また、後述する導電性粒子１Ｂ及び導電性粒子１Ｃも、導電性粒子１と同様にして得ることができる。 The conductive particles 1 can be obtained, for example, by using the conductive particle body 11 to which the flux-containing particles 12 are attached before the flux film 13 is arranged, and forming the flux film 13 by flux treatment. Conductive particles 1B and 1C, which will be described later, can also be obtained in the same manner as the conductive particles 1.
　図２は、本発明の第２の実施形態に係る導電性粒子を示す断面図である。 FIG. 2 is a cross-sectional view showing conductive particles according to the second embodiment of the present invention.
　図２に示す導電性粒子１Ａは、導電性粒子本体１１Ａと、複数のフラックス含有粒子１２Ａと、フラックス膜１３Ａとを備える。導電性粒子１Ａでは、導電性粒子本体１１Ａが、基材粒子２１Ａと、基材粒子２１Ａの外側に配置された導電部２２Ａとを備える。導電性粒子１Ａでは、フラックス含有粒子１２Ａが、導電性粒子本体１１Ａの外側に配置されている。導電性粒子１Ａでは、フラックス膜１３Ａが、導電性粒子本体１１Ａの外側に配置されている。導電部２２Ａは、基材粒子２１Ａの表面上に配置されており、基材粒子２１Ａに接している。導電性粒子１Ａでは、フラックス含有粒子１２Ａが、フラックス膜１３Ａを介して、導電性粒子本体１１Ａ（導電部２２Ａ）の表面上に配置されている。導電性粒子１Ａでは、フラックス含有粒子１２Ａが、フラックス膜１３Ａの表面上に配置されている。フラックス含有粒子１２Ａは、導電性粒子本体１１Ａに接しておらず、フラックス膜１３Ａに接している。導電性粒子１Ａでは、フラックス膜１３Ａが、導電性粒子本体１１Ａ（導電部２２Ａ）の表面上に配置されており、導電性粒子本体１１Ａ（導電部２２Ａ）と接している。導電性粒子１Ａでは、フラックス膜１３Ａが、導電性粒子本体１１Ａの表面（導電部２２Ａの表面）のみを覆っている。導電性粒子１Ａでは、フラックス膜１３Ａは、フラックス含有粒子１２Ａの表面を覆っていない。導電性粒子１Ａでは、フラックス膜１３Ａは、導電性粒子本体１１Ａとフラックス含有粒子１２Ａとの間に配置されている。 A conductive particle 1A shown in FIG. 2 includes a conductive particle body 11A, a plurality of flux-containing particles 12A, and a flux film 13A. In the conductive particle 1A, the conductive particle main body 11A includes a base particle 21A and a conductive portion 22A arranged outside the base particle 21A. In the conductive particles 1A, the flux-containing particles 12A are arranged outside the conductive particle body 11A. In the conductive particle 1A, the flux film 13A is arranged outside the conductive particle main body 11A. The conductive portion 22A is arranged on the surface of the substrate particle 21A and is in contact with the substrate particle 21A. In the conductive particles 1A, the flux-containing particles 12A are arranged on the surface of the conductive particle body 11A (conductive portion 22A) via the flux film 13A. In conductive particles 1A, flux-containing particles 12A are arranged on the surface of flux film 13A. The flux-containing particles 12A are not in contact with the conductive particle body 11A, but are in contact with the flux film 13A. In the conductive particles 1A, the flux film 13A is arranged on the surface of the conductive particle body 11A (conductive portion 22A) and is in contact with the conductive particle body 11A (conductive portion 22A). In the conductive particles 1A, the flux film 13A covers only the surface of the conductive particle body 11A (the surface of the conductive portion 22A). In the conductive particles 1A, the flux film 13A does not cover the surfaces of the flux-containing particles 12A. In the conductive particles 1A, the flux film 13A is arranged between the conductive particle body 11A and the flux-containing particles 12A.
　導電性粒子１と導電性粒子１Ａとでは、フラックス含有粒子及びフラックス膜の構成が異なる。上記フラックス含有粒子と上記導電部との間に、上記フラックス膜があってもよく、上記フラックス膜がなくてもよい。上記フラックス膜は、上記フラックス含有粒子の表面を覆っていてもよく、覆っていなくてもよい。 The conductive particles 1 and the conductive particles 1A have different configurations of the flux-containing particles and the flux film. The flux film may or may not exist between the flux-containing particles and the conductive portion. The flux film may or may not cover the surface of the flux-containing particles.
　導電性粒子１Ａは、例えば、フラックス含有粒子１２Ａ及びフラックス膜１３Ａを配置する前の導電性粒子本体１１Ａを用いて、フラックス処理によりフラックス膜１３Ａを形成した後、フラックス膜１３Ａにフラックス含有粒子１２Ａを付着させることで、得ることができる。 For the conductive particles 1A, for example, the flux-containing particles 12A and the conductive particle main body 11A before the flux film 13A is arranged are used to form the flux film 13A by a flux treatment, and then the flux-containing particles 12A are applied to the flux film 13A. You can get it by attaching it.
　図３は、本発明の第３の実施形態に係る導電性粒子を示す断面図である。 FIG. 3 is a cross-sectional view showing conductive particles according to a third embodiment of the present invention.
　図３に示す導電性粒子１Ｂは、導電性粒子本体１１Ｂと、複数のフラックス含有粒子１２Ｂと、フラックス膜１３Ｂとを備える。導電性粒子１Ｂでは、導電性粒子本体１１Ｂが、基材粒子２１Ｂと、基材粒子２１Ｂの外側に配置された導電部２２Ｂとを備える。導電性粒子１Ｂでは、フラックス含有粒子１２Ｂが、導電性粒子本体１１Ｂの外側に配置されている。導電性粒子１Ｂでは、フラックス膜１３Ｂが、導電性粒子本体１１Ｂの外側に配置されている。導電部２２Ｂは、基材粒子２１Ｂの表面上に配置されており、基材粒子２１Ｂに接している。導電性粒子１Ｂでは、フラックス含有粒子１２Ｂが、導電性粒子本体１１Ｂ（導電部２２Ｂ）の表面上に配置されており、導電部２２Ｂと接している。導電性粒子１Ｂでは、フラックス膜１３Ｂが、導電性粒子本体１１Ｂ（導電部２２Ｂ）の表面上に配置されており、導電性粒子本体１１Ｂ（導電部２２Ｂ）と接している。 A conductive particle 1B shown in FIG. 3 includes a conductive particle body 11B, a plurality of flux-containing particles 12B, and a flux film 13B. In the conductive particle 1B, the conductive particle main body 11B includes the base particle 21B and the conductive part 22B arranged outside the base particle 21B. In the conductive particles 1B, the flux-containing particles 12B are arranged outside the conductive particle body 11B. In the conductive particle 1B, the flux film 13B is arranged outside the conductive particle main body 11B. The conductive portion 22B is arranged on the surface of the substrate particle 21B and is in contact with the substrate particle 21B. In the conductive particles 1B, the flux-containing particles 12B are arranged on the surface of the conductive particle body 11B (conductive portion 22B) and are in contact with the conductive portion 22B. In the conductive particles 1B, the flux film 13B is arranged on the surface of the conductive particle body 11B (conductive portion 22B) and is in contact with the conductive particle body 11B (conductive portion 22B).
　導電性粒子１Ｂでは、導電部２２Ｂが、２層の導電層である。導電部２２Ｂは、第１の導電部２２ＢＡと、第２の導電部２２ＢＢとを備える。導電部２２Ｂでは、第１の導電部２２ＢＡが、基材粒子２１Ｂの外側に配置されており、第２の導電部２２ＢＢが、第１の導電部２２ＢＡの外側に配置されている。導電部２２Ｂでは、第１の導電部２２ＢＡが、基材粒子２１Ｂの表面上に積層されており、第２の導電部２２ＢＢが、第１の導電部２２ＢＡの表面上に積層されている。 In the conductive particles 1B, the conductive portion 22B is a two-layered conductive layer. The conductive portion 22B includes a first conductive portion 22BA and a second conductive portion 22BB. In the conductive portions 22B, the first conductive portions 22BA are arranged outside the base particles 21B, and the second conductive portions 22BB are arranged outside the first conductive portions 22BA. In the conductive portion 22B, the first conductive portion 22BA is laminated on the surface of the substrate particle 21B, and the second conductive portion 22BB is laminated on the surface of the first conductive portion 22BA.
　導電性粒子１と導電性粒子１Ｂとでは、導電部の構成が異なる。導電部は、単層の導電層であってもよく、多層の導電層であってもよい。 The configuration of the conductive portion is different between the conductive particles 1 and the conductive particles 1B. The conductive portion may be a single conductive layer or multiple conductive layers.
　図４は、本発明の第４の実施形態に係る導電性粒子を示す断面図である。 FIG. 4 is a cross-sectional view showing conductive particles according to the fourth embodiment of the present invention.
　図４に示す導電性粒子１Ｃは、導電性粒子本体１１Ｃと、複数のフラックス含有粒子１２Ｃと、フラックス膜１３Ｃとを備える。導電性粒子１Ｃでは、導電性粒子本体１１Ｃが、基材粒子２１Ｃと、基材粒子２１Ｃの外側に配置された導電部２２Ｃと、基材粒子２１Ｃの外側に配置された複数の芯物質２３Ｃとを備える。導電部２２Ｃは、基材粒子２１Ｃと、芯物質２３Ｃとを被覆している。芯物質２３Ｃを導電部２２Ｃが被覆していることにより、導電性粒子本体１１Ｃは表面に、複数の突起１１Ｃａを有する。芯物質２３Ｃにより導電部２２Ｃの表面が隆起されており、複数の突起１１Ｃａが形成されている。 A conductive particle 1C shown in FIG. 4 includes a conductive particle body 11C, a plurality of flux-containing particles 12C, and a flux film 13C. In the conductive particle 1C, the conductive particle body 11C is composed of a base particle 21C, a conductive portion 22C arranged outside the base particle 21C, and a plurality of core substances 23C arranged outside the base particle 21C. Prepare. The conductive portion 22C covers the substrate particles 21C and the core substance 23C. By covering the core substance 23C with the conductive portion 22C, the conductive particle main body 11C has a plurality of protrusions 11Ca on the surface. The core material 23C raises the surface of the conductive portion 22C, forming a plurality of projections 11Ca.
　導電性粒子１と導電性粒子１Ｃとでは、芯物質の使用の有無、及び導電性粒子本体における突起の有無が異なる。導電性粒子本体は表面に、突起を有していてもよく、突起を有していなくてもよい。 The conductive particles 1 and 1C differ in the presence or absence of the use of a core substance and the presence or absence of protrusions on the conductive particle body. The conductive particle body may or may not have projections on the surface.
　以下、導電性粒子の他の詳細を説明する。 Other details of the conductive particles will be described below.
　なお、本明細書において、「（メタ）アクリレート」は、アクリレートとメタクリレートとを示す。「（メタ）アクリル」は、アクリルとメタクリルとを示す。「（メタ）アクリロイル」は、アクリロイルとメタクリロイルとを示す。 In this specification, "(meth)acrylate" indicates acrylate and methacrylate. "(Meth)acryl" indicates acryl and methacryl. "(Meth)acryloyl" indicates acryloyl and methacryloyl.
　上記導電性粒子の粒子径は、好ましくは１μｍ以上、より好ましくは１０μｍ以上であり、好ましくは５０μｍ以下、より好ましくは４０μｍ以下である。上記導電性粒子の粒子径が、上記下限以上及び上記上限以下であると、上記導電性粒子を用いて電極間を接続した場合に、導電性粒子と電極との接触面積が十分に大きくなり、かつ導電部を形成する際に凝集した導電性粒子が形成され難くなる。また、導電性粒子本体を介して接続された電極間の間隔が大きくなりすぎず、かつ導電部が基材粒子の表面から剥離し難くなる。 The particle diameter of the conductive particles is preferably 1 μm or more, more preferably 10 μm or more, and preferably 50 μm or less, more preferably 40 μm or less. When the particle diameter of the conductive particles is the lower limit or more and the upper limit or less, when the electrodes are connected using the conductive particles, the contact area between the conductive particles and the electrodes is sufficiently large, In addition, it becomes difficult to form agglomerated conductive particles when forming the conductive portion. Also, the distance between the electrodes connected via the conductive particle main body does not become too large, and the conductive portion is less likely to peel off from the surface of the base particle.
　上記導電性粒子本体の粒子径は、好ましくは１μｍ以上、より好ましくは１０μｍ以上であり、好ましくは５０μｍ以下、より好ましくは４０μｍ以下である。上記導電性粒子本体の粒子径が、上記下限以上及び上記上限以下であると、上記導電性粒子を用いて電極間を接続した場合に、導電性粒子本体と電極との接触面積が十分に大きくなり、かつ導電部を形成する際に凝集した導電性粒子本体が形成され難くなる。また、導電性粒子本体を介して接続された電極間の間隔が大きくなりすぎず、かつ導電部が基材粒子の表面から剥離し難くなる。 The particle diameter of the conductive particle main body is preferably 1 µm or more, more preferably 10 µm or more, and preferably 50 µm or less, more preferably 40 µm or less. When the particle diameter of the conductive particle body is at least the lower limit and at most the upper limit, when the electrodes are connected using the conductive particle, the contact area between the conductive particle body and the electrode is sufficiently large. In addition, it becomes difficult to form an aggregated conductive particle main body when forming the conductive portion. Also, the distance between the electrodes connected via the conductive particle main body does not become too large, and the conductive portion is less likely to peel off from the surface of the base particle.
　上記導電性粒子及び上記導電性粒子本体の粒子径は、平均粒子径であることが好ましく、該平均粒子径は数平均粒子径を示す。上記導電性粒子及び上記導電性粒子本体の粒子径は、例えば、任意の導電性粒子５０個を電子顕微鏡又は光学顕微鏡にて観察し、各導電性粒子及び各導電性粒子本体の粒子径の平均値を算出することや、レーザー回折式粒度分布測定を行うことにより求められる。 The particle size of the conductive particles and the conductive particle main body is preferably an average particle size, and the average particle size indicates a number average particle size. The particle diameters of the conductive particles and the conductive particle main body are, for example, 50 arbitrary conductive particles are observed with an electron microscope or an optical microscope, and the average particle diameter of each conductive particle and each conductive particle main body. It can be obtained by calculating the value or performing laser diffraction particle size distribution measurement.
　電極間の導通信頼性をより一層効果的に高める観点からは、上記導電性粒子及び上記導電性粒子本体の粒子径の変動係数（ＣＶ値）は、好ましくは１０％以下、より好ましくは５％以下である。 From the viewpoint of more effectively increasing the reliability of conduction between electrodes, the coefficient of variation (CV value) of the particle size of the conductive particles and the conductive particle main body is preferably 10% or less, more preferably 5%. It is below.
　上記変動係数（ＣＶ値）は、以下のようにして測定できる。 The coefficient of variation (CV value) can be measured as follows.
　ＣＶ値（％）＝（ρ／Ｄｎ）×１００
　ρ：導電性粒子又は導電性粒子本体の粒子径の標準偏差
　Ｄｎ：導電性粒子又は導電性粒子本体の粒子径の平均値 CV value (%) = (ρ/Dn) × 100
ρ: standard deviation of the particle size of the conductive particles or the main body of the conductive particles Dn: the average value of the particle size of the conductive particles or the main body of the conductive particles
　上記導電性粒子及び上記導電性粒子本体の形状は特に限定されない。上記導電性粒子及び上記導電性粒子本体の形状は、球状であってもよく、球状以外の形状であってもよく、扁平状等であってもよい。 The shape of the conductive particles and the main body of the conductive particles is not particularly limited. The conductive particles and the conductive particle main body may have a spherical shape, a shape other than a spherical shape, or a flat shape.
　＜基材粒子＞
　上記基材粒子としては、樹脂粒子、金属粒子を除く無機粒子、有機無機ハイブリッド粒子及び金属粒子等が挙げられる。上記基材粒子は、金属粒子を除く基材粒子であることが好ましく、樹脂粒子、金属粒子を除く無機粒子又は有機無機ハイブリッド粒子であることがより好ましい。上記基材粒子は、コアと、該コアの表面上に配置されたシェルとを備えるコアシェル粒子であってもよい。上記コアが有機コアであってもよく、上記シェルが無機シェルであってもよい。 <Base material particles>
Examples of the substrate particles include resin particles, inorganic particles other than metal particles, organic-inorganic hybrid particles, and metal particles. The substrate particles are preferably substrate particles other than metal particles, and more preferably resin particles, inorganic particles other than metal particles, or organic-inorganic hybrid particles. The substrate particles may be core-shell particles comprising a core and a shell arranged on the surface of the core. The core may be an organic core and the shell may be an inorganic shell.
　上記樹脂粒子の材料としては、ポリエチレン、ポリプロピレン、ポリスチレン、ポリ塩化ビニル、ポリ塩化ビニリデン、ポリイソブチレン、及びポリブタジエン等のポリオレフィン樹脂；ポリメチルメタクリレート及びポリメチルアクリレート等のアクリル樹脂；ポリカーボネート、ポリアミド、フェノールホルムアルデヒド樹脂、メラミンホルムアルデヒド樹脂、ベンゾグアナミンホルムアルデヒド樹脂、尿素ホルムアルデヒド樹脂、フェノール樹脂、メラミン樹脂、ベンゾグアナミン樹脂、尿素樹脂、エポキシ樹脂、不飽和ポリエステル樹脂、飽和ポリエステル樹脂、ポリエチレンテレフタレート、ポリスルホン、ポリフェニレンオキサイド、ポリアセタール、ポリイミド、ポリアミドイミド、ポリエーテルエーテルケトン、ポリエーテルスルホン、及びジビニルベンゼン重合体等が挙げられる。上記ジビニルベンゼン重合体は、ジビニルベンゼン共重合体であってもよい。上記ジビニルベンゼン共重合体等としては、ジビニルベンゼン－スチレン共重合体及びジビニルベンゼン－（メタ）アクリル酸エステル共重合体等が挙げられる。上記樹脂粒子の硬度を好適な範囲に容易に制御できるので、上記樹脂粒子の材料は、エチレン性不飽和基を有する重合性単量体を１種又は２種以上重合させた重合体であることが好ましい。 Materials for the resin particles include polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene, and polybutadiene; acrylic resins such as polymethyl methacrylate and polymethyl acrylate; polycarbonate, polyamide, and phenol formaldehyde. Resin, melamine formaldehyde resin, benzoguanamine formaldehyde resin, urea formaldehyde resin, phenolic resin, melamine resin, benzoguanamine resin, urea resin, epoxy resin, unsaturated polyester resin, saturated polyester resin, polyethylene terephthalate, polysulfone, polyphenylene oxide, polyacetal, polyimide, Examples include polyamideimide, polyetheretherketone, polyethersulfone, and divinylbenzene polymer. The divinylbenzene polymer may be a divinylbenzene copolymer. Examples of the divinylbenzene copolymer and the like include a divinylbenzene-styrene copolymer and a divinylbenzene-(meth)acrylate copolymer. Since the hardness of the resin particles can be easily controlled within a suitable range, the material of the resin particles is a polymer obtained by polymerizing one or more polymerizable monomers having an ethylenically unsaturated group. is preferred.
　上記樹脂粒子を、エチレン性不飽和基を有する重合性単量体を重合させて得る場合には、該エチレン性不飽和基を有する重合性単量体としては、非架橋性の単量体と架橋性の単量体とが挙げられる。 When the resin particles are obtained by polymerizing a polymerizable monomer having an ethylenically unsaturated group, the polymerizable monomer having an ethylenically unsaturated group may be a non-crosslinking monomer. and crosslinkable monomers.
　上記非架橋性の単量体としては、スチレン、及びα－メチルスチレン等のスチレン系単量体；（メタ）アクリル酸、マレイン酸、及び無水マレイン酸等のカルボキシル基含有単量体；メチル（メタ）アクリレート、エチル（メタ）アクリレート、プロピル（メタ）アクリレート、ブチル（メタ）アクリレート、２－エチルヘキシル（メタ）アクリレート、ラウリル（メタ）アクリレート、セチル（メタ）アクリレート、ステアリル（メタ）アクリレート、シクロヘキシル（メタ）アクリレート、及びイソボルニル（メタ）アクリレート等のアルキル（メタ）アクリレート化合物；２－ヒドロキシエチル（メタ）アクリレート、グリセロール（メタ）アクリレート、ポリオキシエチレン（メタ）アクリレート、及びグリシジル（メタ）アクリレート等の酸素原子含有（メタ）アクリレート化合物；（メタ）アクリロニトリル等のニトリル含有単量体；メチルビニルエーテル、エチルビニルエーテル、及びプロピルビニルエーテル等のビニルエーテル化合物；酢酸ビニル、酪酸ビニル、ラウリン酸ビニル、及びステアリン酸ビニル等の酸ビニルエステル化合物；エチレン、プロピレン、イソプレン、及びブタジエン等の不飽和炭化水素；トリフルオロメチル（メタ）アクリレート、ペンタフルオロエチル（メタ）アクリレート、塩化ビニル、フッ化ビニル、及びクロルスチレン等のハロゲン含有単量体等が挙げられる。 Examples of the non-crosslinkable monomers include styrene and styrene-based monomers such as α-methylstyrene; carboxyl group-containing monomers such as (meth)acrylic acid, maleic acid, and maleic anhydride; methyl ( meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl ( Alkyl (meth)acrylate compounds such as meth)acrylate and isobornyl (meth)acrylate; 2-hydroxyethyl (meth)acrylate, glycerol (meth)acrylate, polyoxyethylene (meth)acrylate, and glycidyl (meth)acrylate, etc. Oxygen atom-containing (meth)acrylate compounds; nitrile-containing monomers such as (meth)acrylonitrile; vinyl ether compounds such as methyl vinyl ether, ethyl vinyl ether, and propyl vinyl ether; vinyl acetate, vinyl butyrate, vinyl laurate, and vinyl stearate, etc. acid vinyl ester compounds of; unsaturated hydrocarbons such as ethylene, propylene, isoprene, and butadiene; halogens such as trifluoromethyl (meth)acrylate, pentafluoroethyl (meth)acrylate, vinyl chloride, vinyl fluoride, and chlorostyrene A contained monomer etc. are mentioned.
　上記架橋性の単量体としては、テトラメチロールメタンテトラ（メタ）アクリレート、テトラメチロールメタントリ（メタ）アクリレート、テトラメチロールメタンジ（メタ）アクリレート、トリメチロールプロパントリ（メタ）アクリレート、ジペンタエリスリトールヘキサ（メタ）アクリレート、ジペンタエリスリトールペンタ（メタ）アクリレート、ジペンタエリスリトールポリ（メタ）アクリレート、ペンタエリスリトールテトラ（メタ）アクリレート、グリセロールトリ（メタ）アクリレート、グリセロールジ（メタ）アクリレート、（ポリ）エチレングリコールジ（メタ）アクリレート、（ポリ）プロピレングリコールジ（メタ）アクリレート、（ポリ）テトラメチレングリコールジ（メタ）アクリレート、及び１，４－ブタンジオールジ（メタ）アクリレート等の多官能（メタ）アクリレート化合物；トリアリル（イソ）シアヌレート、トリアリルトリメリテート、ジビニルベンゼン、ジアリルフタレート、ジアリルアクリルアミド、ジアリルエーテル、並びに、γ－（メタ）アクリロキシプロピルトリメトキシシラン、トリメトキシシリルスチレン、及びビニルトリメトキシシラン等のシラン含有単量体等が挙げられる。上記樹脂粒子のガラス転移温度においてもフラックス含有粒子が形状を保つ観点からは、上記架橋性の単量体は、（ポリ）エチレングリコールジ（メタ）アクリレート、トリメチロールプロパントリ（メタ）アクリレート、ペンタエリスリトールテトラ（メタ）アクリレート、又はジペンタエリスリトールポリ（メタ）アクリレートであることが好ましい。 Examples of the crosslinkable monomer include tetramethylolmethane tetra(meth)acrylate, tetramethylolmethane tri(meth)acrylate, tetramethylolmethane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol hexa (meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol poly(meth)acrylate, pentaerythritol tetra(meth)acrylate, glycerol tri(meth)acrylate, glycerol di(meth)acrylate, (poly)ethylene glycol Polyfunctional (meth)acrylate compounds such as di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, (poly)tetramethylene glycol di(meth)acrylate, and 1,4-butanediol di(meth)acrylate triallyl (iso) cyanurate, triallyl trimellitate, divinylbenzene, diallyl phthalate, diallyl acrylamide, diallyl ether, and γ-(meth)acryloxypropyltrimethoxysilane, trimethoxysilylstyrene, vinyltrimethoxysilane, etc. and silane-containing monomers. From the viewpoint of maintaining the shape of the flux-containing particles even at the glass transition temperature of the resin particles, the crosslinkable monomers include (poly)ethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, penta Erythritol tetra(meth)acrylate or dipentaerythritol poly(meth)acrylate is preferred.
　上記エチレン性不飽和基を有する重合性単量体を、公知の方法により重合させることで、上記樹脂粒子を得ることができる。この方法としては、例えば、ラジカル重合開始剤の存在下で懸濁重合する方法、並びに非架橋の種粒子を用いてラジカル重合開始剤とともに単量体を膨潤させて重合する方法等が挙げられる。 The resin particles can be obtained by polymerizing the polymerizable monomer having the ethylenically unsaturated group by a known method. Examples of this method include a method of suspension polymerization in the presence of a radical polymerization initiator, and a method of polymerizing by swelling a monomer together with a radical polymerization initiator using uncrosslinked seed particles.
　上記基材粒子が金属を除く無機粒子又は有機無機ハイブリッド粒子である場合には、基材粒子を形成するための無機物としては、シリカ、アルミナ、チタン酸バリウム、ジルコニア及びカーボンブラック等が挙げられる。上記無機物は、金属ではないことが好ましい。上記シリカにより形成された粒子としては、例えば、加水分解性のアルコキシシリル基を２つ以上有するケイ素化合物を加水分解して架橋重合体粒子を形成した後に、必要に応じて焼成を行うことにより得られる粒子が挙げられる。上記有機無機ハイブリッド粒子としては、例えば、架橋したアルコキシシリルポリマーとアクリル樹脂とにより形成された有機無機ハイブリッド粒子等が挙げられる。 When the substrate particles are inorganic particles excluding metals or organic-inorganic hybrid particles, examples of inorganic substances for forming the substrate particles include silica, alumina, barium titanate, zirconia, and carbon black. Preferably, the inorganic substance is not a metal. The particles formed of silica can be obtained, for example, by hydrolyzing a silicon compound having two or more hydrolyzable alkoxysilyl groups to form crosslinked polymer particles, followed by firing as necessary. particles that can be used. Examples of the organic-inorganic hybrid particles include organic-inorganic hybrid particles formed from a crosslinked alkoxysilyl polymer and an acrylic resin.
　上記有機無機ハイブリッド粒子は、コアと、該コアの表面上に配置されたシェルとを有するコアシェル型の有機無機ハイブリッド粒子であることが好ましい。上記コアが有機コアであることが好ましい。上記シェルが無機シェルであることが好ましい。電極間の接続抵抗を効果的に低くする観点からは、上記基材粒子は、有機コアと上記有機コアの表面上に配置された無機シェルとを有する有機無機ハイブリッド粒子であることが好ましい。 The organic-inorganic hybrid particles are preferably core-shell type organic-inorganic hybrid particles having a core and a shell disposed on the surface of the core. It is preferred that the core is an organic core. Preferably, the shell is an inorganic shell. From the viewpoint of effectively reducing the connection resistance between electrodes, the substrate particles are preferably organic-inorganic hybrid particles having an organic core and an inorganic shell disposed on the surface of the organic core.
　上記有機コアの材料としては、上述した樹脂粒子の材料等が挙げられる。 Examples of the material for the organic core include the materials for the resin particles described above.
　上記無機シェルの材料としては、上述した基材粒子の材料として挙げた無機物が挙げられる。上記無機シェルの材料は、シリカであることが好ましい。上記無機シェルは、上記コアの表面上で、金属アルコキシドをゾルゲル法によりシェル状物とした後、該シェル状物を焼成させることにより形成されていることが好ましい。上記金属アルコキシドはシランアルコキシドであることが好ましい。上記無機シェルはシランアルコキシドにより形成されていることが好ましい。 Examples of the material for the inorganic shell include the inorganic substances listed above as the material for the substrate particles. The inorganic shell material is preferably silica. The inorganic shell is preferably formed by forming a metal alkoxide into a shell-like material on the surface of the core by a sol-gel method, and then firing the shell-like material. The metal alkoxide is preferably silane alkoxide. The inorganic shell is preferably made of silane alkoxide.
　上記基材粒子が金属粒子である場合に、該金属粒子の材料である金属としては、銀、銅、ニッケル、ケイ素、金及びチタン等が挙げられる。 When the substrate particles are metal particles, examples of metals that are materials of the metal particles include silver, copper, nickel, silicon, gold, and titanium.
　上記基材粒子の粒子径は、好ましくは０．５μｍ以上、より好ましくは９．５μｍ以上であり、好ましくは４９．９５μｍ以下、より好ましくは３９．９５μｍ以下である。上記基材粒子の粒子径が、上記下限以上及び上記上限以下であると、電極間の間隔が小さくなり、かつ導電部の厚みを厚くしても、小さい導電性粒子が得られる。さらに基材粒子の表面に導電部を形成する際に凝集し難くなり、凝集した導電性粒子が形成され難くなる。 The particle diameter of the substrate particles is preferably 0.5 μm or more, more preferably 9.5 μm or more, and preferably 49.95 μm or less, more preferably 39.95 μm or less. When the particle size of the substrate particles is equal to or more than the lower limit and equal to or less than the upper limit, small conductive particles can be obtained even when the distance between the electrodes is small and the thickness of the conductive portion is increased. Furthermore, it becomes difficult to aggregate when forming the conductive portion on the surface of the substrate particles, and it becomes difficult to form aggregated conductive particles.
　上記基材粒子の形状は特に限定されない。上記基材粒子の形状は、球状であってもよく、球状以外の形状であってもよく、扁平状等であってもよい。 The shape of the substrate particles is not particularly limited. The shape of the substrate particles may be spherical, may be other than spherical, or may be flat.
　上記基材粒子の粒子径は、平均粒子径であることが好ましく、該平均粒子径は数平均粒子径を示す。上記基材粒子の粒子径は粒度分布測定装置等を用いて求められる。基材粒子の粒子径は、任意の基材粒子５０個を電子顕微鏡又は光学顕微鏡にて観察し、平均値を算出することにより求めることが好ましい。導電性粒子において、上記基材粒子の粒子径を測定する場合には、例えば、以下のようにして測定できる。 The particle size of the substrate particles is preferably the average particle size, and the average particle size indicates the number average particle size. The particle size of the substrate particles is determined using a particle size distribution analyzer or the like. The particle diameter of the substrate particles is preferably determined by observing 50 arbitrary substrate particles with an electron microscope or an optical microscope and calculating the average value. When measuring the particle size of the substrate particles of the conductive particles, it can be measured, for example, as follows.
　導電性粒子の含有量が３０重量％となるように、Ｋｕｌｚｅｒ社製「テクノビット４０００」に添加し、分散させて、導電性粒子を含む検査用埋め込み樹脂体を作製する。上記検査用埋め込み樹脂体中に分散した導電性粒子の中心付近を通るようにイオンミリング装置（日立ハイテクノロジーズ社製「ＩＭ４０００」）を用いて、導電性粒子の断面を切り出す。そして、電界放射型走査型電子顕微鏡（ＦＥ－ＳＥＭ）を用いて、画像倍率を２５０００倍に設定し、５０個の導電性粒子を無作為に選択し、各導電性粒子の基材粒子を観察する。各導電性粒子における基材粒子の粒子径を計測し、それらを算術平均して基材粒子の粒子径とする。 "Technovit 4000" manufactured by Kulzer is added so that the content of the conductive particles is 30% by weight, and dispersed to prepare an embedded resin body for inspection containing the conductive particles. Using an ion milling device (“IM4000” manufactured by Hitachi High-Technologies Corporation), a cross section of the conductive particles is cut out so as to pass through the vicinity of the center of the conductive particles dispersed in the embedded resin body for inspection. Then, using a field emission scanning electron microscope (FE-SEM), set the image magnification to 25000 times, randomly select 50 conductive particles, and observe the base particles of each conductive particle. do. The particle diameter of the base material particles in each conductive particle is measured, and the arithmetic mean is taken as the particle size of the base material particles.
　＜芯物質及び突起＞
　上記導電性粒子本体は、上記導電部の外表面に突起を有することが好ましい。上記突起は、複数であることが好ましい。一般に、導電性粒子本体と接触する電極の表面には、酸化被膜が形成されていることが多い。導電部の表面に突起を有する導電性粒子本体を用いた場合には、導電接続時に、突起により上記酸化被膜を効果的に排除できる。このため、電極と導電部とがより一層確実に接触し、導電性粒子本体と電極との接触面積を十分に大きくすることができ、接続抵抗をより一層効果的に低くすることができる。さらに、導電性粒子がバインダーに分散されて導電材料として用いられる場合に、導電性粒子本体の突起によって、導電性粒子本体と電極との間のバインダーをより一層効果的に排除できる。このため、導電性粒子本体と電極との接触面積を十分に大きくすることができ、接続抵抗をより一層効果的に低くすることができる。上記導電性粒子本体は、上記基材粒子の外側に、芯物質を有することが好ましい。上記導電性粒子本体は、上記基材粒子の表面上に、芯物質を有することが好ましい。 <Core substance and protrusion>
The conductive particle body preferably has projections on the outer surface of the conductive portion. It is preferable that the protrusion is plural. In general, an oxide film is often formed on the surface of the electrode that contacts the main body of the conductive particles. When a conductive particle body having projections on the surface of the conductive portion is used, the oxide film can be effectively removed by the projections at the time of conductive connection. As a result, the electrode and the conductive portion can be brought into contact with each other more reliably, the contact area between the conductive particle body and the electrode can be sufficiently increased, and the connection resistance can be more effectively reduced. Furthermore, when the conductive particles are dispersed in a binder and used as a conductive material, the protrusions of the conductive particle bodies can more effectively eliminate the binder between the conductive particle bodies and the electrode. Therefore, the contact area between the conductive particle body and the electrode can be sufficiently increased, and the connection resistance can be further effectively reduced. The conductive particle main body preferably has a core substance on the outside of the substrate particles. The conductive particle body preferably has a core substance on the surface of the substrate particle.
　導電性粒子本体の表面に突起を形成する方法としては、以下の方法等が挙げられる。基材粒子の表面に芯物質を付着させた後、無電解めっきにより導電部を形成する方法。基材粒子の表面に無電解めっきにより導電部を形成した後、芯物質を付着させ、更に無電解めっきにより導電部を形成する方法。基材粒子の表面に無電解めっきにより導電部を形成した後、さらに無電解めっきにより導電部と同じ組成の突起を形成する方法。 Examples of methods for forming projections on the surface of the conductive particle body include the following methods. A method of forming a conductive portion by electroless plating after adhering a core substance to the surface of a substrate particle. A method of forming a conductive portion on the surface of a substrate particle by electroless plating, adhering a core substance, and further forming a conductive portion by electroless plating. A method of forming a conductive portion on the surface of a substrate particle by electroless plating, and then forming projections having the same composition as the conductive portion by electroless plating.
　基材粒子の表面に芯物質を付着させる方法としては、例えば、基材粒子の分散液中に、芯物質を添加し、基材粒子の表面に芯物質を、例えば、ファンデルワールス力により集積させ、付着させる方法、並びに基材粒子を入れた容器に、芯物質を添加し、容器の回転等による機械的な作用により基材粒子の表面に芯物質を付着させる方法等が挙げられる。なかでも、付着させる芯物質の量を制御しやすいため、分散液中の基材粒子の表面に芯物質を集積させ、付着させる方法が好ましい。 As a method for attaching the core substance to the surface of the substrate particles, for example, the core substance is added to the dispersion liquid of the substrate particles, and the core substance is accumulated on the surface of the substrate particles by, for example, Van der Waals force. and a method of adding the core substance to a container containing the base particles and attaching the core substance to the surface of the base particles by mechanical action such as rotation of the container. Among them, the method of accumulating and attaching the core substance to the surface of the substrate particles in the dispersion liquid is preferable because the amount of the core substance to be adhered can be easily controlled.
　上記導電性粒子は、上記基材粒子の外側に第１の導電部を有し、かつ、第１の導電部の外側に第２の導電部を有していてもよい。この場合に、上記第１の導電部の表面に芯物質を付着させてもよい。上記芯物質は、上記第２の導電部により被覆されていることが好ましい。上記芯物質の短径は、好ましくは０．０５μｍ以上であり、好ましくは０．５μｍ以下である。導電性粒子は、基材粒子の表面上に第１の導電部を形成し、次に第１の導電部の表面上に芯物質を付着させた後、第１の導電部及び芯物質の表面上に第２の導電部を形成することにより得られていることが好ましい。 The conductive particles may have a first conductive portion on the outside of the base particles and a second conductive portion on the outside of the first conductive portion. In this case, a core substance may be adhered to the surface of the first conductive portion. The core substance is preferably covered with the second conductive portion. The short diameter of the core substance is preferably 0.05 μm or more and preferably 0.5 μm or less. The conductive particles form the first conductive portion on the surface of the substrate particle, then attach the core substance on the surface of the first conductive portion, and then the surface of the first conductive portion and the core substance It is preferably obtained by forming a second conductive portion thereon.
　上記芯物質を構成する物質としては、導電性物質及び非導電性物質が挙げられる。上記導電性物質としては、例えば、金属、金属の酸化物、黒鉛等の導電性非金属及び導電性ポリマー等が挙げられる。上記導電性ポリマーとしては、ポリアセチレン等が挙げられる。上記非導電性物質としては、シリカ、アルミナ及びジルコニア等が挙げられる。導通信頼性を高める観点からは、上記芯物質を構成する物質は、金属であることが好ましい。上記芯物質は、金属粒子であることが好ましい。 　Conductive substances and non-conductive substances can be mentioned as substances that constitute the core substance. Examples of the conductive substance include metals, metal oxides, conductive nonmetals such as graphite, and conductive polymers. Polyacetylene etc. are mentioned as said conductive polymer. Silica, alumina, zirconia, and the like are mentioned as the non-conductive substance. From the standpoint of enhancing conduction reliability, the substance constituting the core substance is preferably a metal. The core substance is preferably metal particles.
　上記金属としては、例えば、金、銀、銅、白金、亜鉛、鉄、鉛、錫、アルミニウム、コバルト、インジウム、ニッケル、クロム、チタン、アンチモン、ビスマス、ゲルマニウム及びカドミウム等の金属、並びに錫－鉛合金、錫－銅合金、錫－銀合金、錫－鉛－銀合金及び炭化タングステン等の２種類以上の金属で構成される合金等が挙げられる。なかでも、ニッケル、銅、銀又は金が好ましい。上記芯物質を構成する金属は、上記導電部（導電層）を構成する金属と同じであってもよく、異なっていてもよい。 Examples of the above metals include metals such as gold, silver, copper, platinum, zinc, iron, lead, tin, aluminum, cobalt, indium, nickel, chromium, titanium, antimony, bismuth, germanium and cadmium, and tin-lead. 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 forming the core substance may be the same as or different from the metal forming the conductive portion (conductive layer).
　上記芯物質の形状は特に限定されない。芯物質の形状は塊状であることが好ましい。芯物質としては、例えば、粒子状の塊、複数の微小粒子が凝集した凝集塊、及び不定形の塊等が挙げられる。 The shape of the core substance is not particularly limited. The shape of the core substance is preferably massive. The core substance includes, for example, particulate lumps, agglomerates in which a plurality of microparticles are aggregated, irregular lumps, and the like.
　複数の上記突起の平均高さは、好ましくは０．００１μｍ以上、より好ましくは０．０５μｍ以上、好ましくは０．９μｍ以下、より好ましくは０．２μｍ以下である。上記突起の平均高さが上記下限以上及び上記上限以下であると、電極間の接続抵抗を効果的に低くすることができる。 The average height of the plurality of projections is preferably 0.001 μm or more, more preferably 0.05 μm or more, preferably 0.9 μm or less, more preferably 0.2 μm or less. When the average height of the projections is equal to or higher than the lower limit and equal to or lower than the upper limit, the connection resistance between the electrodes can be effectively lowered.
　＜導電部＞
　本発明では、上記導電性粒子は、導電部を表面に有する。上記導電部は、上記基材粒子の表面上に配置されている。 <Conductive part>
In the present invention, the conductive particles have conductive portions on their surfaces. The conductive portion is arranged on the surface of the substrate particle.
　上記導電部は、金属を含むことが好ましい。上記導電部を構成する金属は、特に限定されない。上記金属としては、錫、金、銀、銅、錫、白金、パラジウム、亜鉛、鉛、アルミニウム、コバルト、インジウム、ニッケル、クロム、チタン、アンチモン、ビスマス、ゲルマニウム及びカドミウム、並びにこれらの合金等が挙げられる。また、上記金属として、錫ドープ酸化インジウム（ＩＴＯ）を用いてもよい。上記金属は、１種のみが用いられてもよく、２種以上が併用されてもよい。 The conductive portion preferably contains a metal. The metal forming the conductive portion is not particularly limited. Examples of the metals include tin, gold, silver, copper, tin, platinum, palladium, zinc, lead, aluminum, cobalt, indium, nickel, chromium, titanium, antimony, bismuth, germanium, cadmium, and alloys thereof. be done. Alternatively, tin-doped indium oxide (ITO) may be used as the metal. Only one of the above metals may be used, or two or more thereof may be used in combination.
　導通信頼性をより一層高める観点からは、上記導電部は、錫、ニッケル、銅又は金を含むことが好ましく、錫又はニッケルを含むことがより好ましく、錫を含むことがさらに好ましい。 From the viewpoint of further enhancing conduction reliability, the conductive portion preferably contains tin, nickel, copper or gold, more preferably tin or nickel, and still more preferably tin.
　導通信頼性をより一層高める観点からは、上記導電部は、錫を主金属として含むことが好ましい。導通信頼性をより一層高める観点からは、上記導電部１００重量％中、錫の含有量は１０重量％以上であることが好ましい。導通信頼性をより一層高める観点からは、上記導電部１００重量％中、錫の含有量は、好ましくは１５重量％以上、より好ましくは２０重量％以上、さらに好ましくは２５重量％以上、特に好ましくは３０重量％以上である。上記導電部１００重量％中、錫の含有量は、１００重量％（全量）であってもよい。 From the viewpoint of further improving conduction reliability, the conductive portion preferably contains tin as a main metal. From the viewpoint of further improving conduction reliability, the tin content is preferably 10% by weight or more in 100% by weight of the conductive portion. From the viewpoint of further improving conduction reliability, the content of tin in 100% by weight of the conductive portion is preferably 15% by weight or more, more preferably 20% by weight or more, further preferably 25% by weight or more, and particularly preferably 25% by weight or more. is 30% by weight or more. The content of tin in 100% by weight of the conductive portion may be 100% by weight (total amount).
　上記導電部は、１つの層により形成されていてもよい。上記導電部は、複数の層により形成されていてもよい。すなわち、上記導電部は、２層以上の積層構造を有していてもよい。上記導電部が複数の層により形成されている場合には、最外層を構成する金属は、錫、ニッケル又は金であることが好ましく、錫又はニッケルであることがより好ましく、錫であることがさらに好ましい。最外層を構成する金属がこれらの好ましい金属である場合には、電極間の接続抵抗がより一層低くなる。また、最外層を構成する金属が金である場合には、耐腐食性がより一層高くなる。 The conductive portion may be formed of one layer. The conductive portion may be formed of a plurality of layers. That is, the conductive portion may have a laminated structure of two or more layers. When the conductive portion is formed of a plurality of layers, the metal constituting the outermost layer is preferably tin, nickel or gold, more preferably tin or nickel, and tin. More preferred. When the metal forming the outermost layer is one of these preferred metals, the connection resistance between the electrodes is even lower. Further, when the metal forming the outermost layer is gold, the corrosion resistance is further enhanced.
　上記基材粒子の全表面積１００％中、上記導電部の面積（被覆率）は、好ましくは８０％以上、より好ましくは９０％以上である。上記被覆率の上限は特に限定されない。上記被覆率は９９％以下であってもよい。上記被覆率が、上記下限以上及び上記上限以下であると、電極間を電気的に接続した場合に、導通信頼性をより一層効果的に高めることができる。 Within 100% of the total surface area of the substrate particles, the area (coverage) of the conductive portion is preferably 80% or more, more preferably 90% or more. The upper limit of the coverage rate is not particularly limited. The coverage may be 99% or less. When the coverage is equal to or more than the lower limit and equal to or less than the upper limit, it is possible to further effectively improve the conduction reliability when the electrodes are electrically connected.
　上記導電部の厚みは、好ましくは０．００５μｍ以上、より好ましくは０．０１μｍ以上であり、好ましくは１０μｍ以下、より好ましくは１μｍ以下、さらに好ましくは０．５μｍ以下である。上記導電部の厚みが、上記下限以上及び上記上限以下であると、導通信頼性をより一層効果的に高め、かつ、導電性粒子が硬くなりすぎずに、電極間の接続の際に導電性粒子を十分に変形させることができる。 The thickness of the conductive portion is preferably 0.005 μm or more, more preferably 0.01 μm or more, and preferably 10 μm or less, more preferably 1 μm or less, and even more preferably 0.5 μm or less. When the thickness of the conductive portion is equal to or more than the lower limit and equal to or less than the upper limit, the reliability of conduction is further effectively improved, and the conductive particles do not become too hard, so that the conductive particles can be electrically conductive when connecting between electrodes. Particles can be sufficiently deformed.
　上記導電部が複数の層により形成されている場合に、最外層の導電部の厚みは、好ましくは０．００１μｍ以上、より好ましくは０．０１μｍ以上であり、好ましくは０．５μｍ以下、より好ましくは０．３μｍ以下である。上記最外層の導電部の厚みが、上記下限以上及び上記上限以下であると、最外層の導電部が均一になり、耐腐食性が十分に高くなり、かつ電極間の接続抵抗を十分に低くすることができる。 When the conductive portion is formed of a plurality of layers, the thickness of the conductive portion in the outermost layer is preferably 0.001 μm or more, more preferably 0.01 μm or more, and preferably 0.5 μm or less, and more preferably. is 0.3 μm or less. When the thickness of the conductive portion of the outermost layer is equal to or more than the lower limit and equal to or less than the upper limit, the conductive portion of the outermost layer is uniform, the corrosion resistance is sufficiently high, and the connection resistance between electrodes is sufficiently low. can do.
　上記導電部の厚みは、例えば、透過型電子顕微鏡（ＴＥＭ）を用いて、導電性粒子の断面を観察することにより測定できる。 The thickness of the conductive portion can be measured, for example, by observing the cross section of the conductive particles using a transmission electron microscope (TEM).
　上記基材粒子の表面上に導電部を形成する方法は特に限定されない。上記導電部を形成する方法としては、例えば、無電解めっきによる方法、電気めっきによる方法、物理的な衝突による方法、メカノケミカル反応による方法、物理的蒸着又は物理的吸着による方法、並びに金属粉末もしくは金属粉末とバインダーとを含むペーストを基材粒子の表面にコーティングする方法等が挙げられる。上記導電部を形成する方法は、無電解めっき、電気めっき又は物理的な衝突による方法であることが好ましい。上記物理的蒸着による方法としては、真空蒸着、イオンプレーティング及びイオンスパッタリング等の方法が挙げられる。また、上記物理的な衝突による方法では、例えば、シーターコンポーザ（徳寿工作所社製）等が用いられる。 The method of forming the conductive portion on the surface of the substrate particles is not particularly limited. Methods for forming the conductive portion include, for example, a method by electroless plating, a method by electroplating, a method by physical collision, a method by mechanochemical reaction, a method by physical vapor deposition or physical adsorption, and metal powder or Examples thereof include a method of coating the surface of the substrate particles with a paste containing a metal powder and a binder. The method of forming the conductive portion is preferably electroless plating, electroplating, or a method using physical collision. Methods such as vacuum deposition, ion plating, and ion sputtering can be used as the method by physical vapor deposition. Also, in the method using physical collision, for example, a sheeter composer (manufactured by Tokuju Kosakusho Co., Ltd.) or the like is used.
　＜フラックス含有粒子＞
　上記導電性粒子は、フラックス含有粒子を備える。上記フラックス含有粒子は、上記導電性粒子本体の外側に配置されている。上記フラックス含有粒子は、上記導電性粒子本体の表面上に配置されている。上記フラックス含有粒子は、上記導電部の表面上に配置されている。上記フラックス含有粒子は、フラックス膜などを介して、上記導電性粒子本体又は上記導電部の表面上に配置されていてもよい。上記フラックス含有粒子は、上記導電性粒子本体の表面に接していてもよく、上記導電性粒子本体の表面に接していなくてもよい。上記フラックス含有粒子は、上記導電部の表面に接していてもよく、上記導電部の表面に接していなくてもよい。 <Flux-containing particles>
The conductive particles comprise flux-containing particles. The flux-containing particles are arranged outside the conductive particle body. The flux-containing particles are arranged on the surface of the conductive particle body. The flux-containing particles are arranged on the surface of the conductive portion. The flux-containing particles may be arranged on the surface of the conductive particle body or the conductive portion via a flux film or the like. The flux-containing particles may be in contact with the surface of the conductive particle body, or may not be in contact with the surface of the conductive particle body. The flux-containing particles may be in contact with the surface of the conductive portion, or may not be in contact with the surface of the conductive portion.
　上記フラックス含有粒子は、粒子本体と、フラックスとを含むことが好ましい。 The flux-containing particles preferably contain a particle body and flux.
　上記粒子本体としては、金属粒子を除く無機粒子、樹脂粒子、有機無機ハイブリッド粒子及び金属粒子等が挙げられる。上記粒子本体は、金属粒子を除く無機粒子、又は樹脂粒子であることが好ましく、樹脂粒子であることがより好ましい。 Examples of the particle main body include inorganic particles other than metal particles, resin particles, organic-inorganic hybrid particles, metal particles, and the like. The particle bodies are preferably inorganic particles other than metal particles or resin particles, and more preferably resin particles.
　上記金属粒子を除く無機粒子としては、シリカ、アルミナ、及びチタニア等が挙げられる。上記シリカとしては、多孔質シリカ等が挙げられる。 Examples of inorganic particles other than the metal particles include silica, alumina, and titania. Porous silica etc. are mentioned as said silica.
　上記樹脂粒子の材料としては、ポリエチレン、ポリプロピレン、ポリスチレン、ポリ塩化ビニル、ポリ塩化ビニリデン、ポリイソブチレン、及びポリブタジエン等のポリオレフィン樹脂；ポリメチルメタクリレート及びポリメチルアクリレート等のアクリル樹脂；ポリカーボネート、ポリアミド、フェノールホルムアルデヒド樹脂、メラミンホルムアルデヒド樹脂、ベンゾグアナミンホルムアルデヒド樹脂、尿素ホルムアルデヒド樹脂、フェノール樹脂、メラミン樹脂、ベンゾグアナミン樹脂、尿素樹脂、エポキシ樹脂、不飽和ポリエステル樹脂、飽和ポリエステル樹脂、ポリエチレンテレフタレート、ポリスルホン、ポリフェニレンオキサイド、ポリアセタール、ポリイミド、ポリアミドイミド、ポリエーテルエーテルケトン、ポリエーテルスルホン、及びジビニルベンゼン重合体等が挙げられる。上記ジビニルベンゼン重合体は、ジビニルベンゼン共重合体であってもよい。上記ジビニルベンゼン共重合体等としては、ジビニルベンゼン－スチレン共重合体及びジビニルベンゼン－（メタ）アクリル酸エステル共重合体等が挙げられる。上記樹脂粒子の硬度を好適な範囲に容易に制御できるので、上記樹脂粒子の材料は、重合性単量体を含むことが好ましく、エチレン性不飽和基を有する重合性単量体を１種又は２種以上重合させた重合体であることがより好ましい。 Materials for the resin particles include polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene, and polybutadiene; acrylic resins such as polymethyl methacrylate and polymethyl acrylate; polycarbonate, polyamide, and phenol formaldehyde. Resin, melamine formaldehyde resin, benzoguanamine formaldehyde resin, urea formaldehyde resin, phenolic resin, melamine resin, benzoguanamine resin, urea resin, epoxy resin, unsaturated polyester resin, saturated polyester resin, polyethylene terephthalate, polysulfone, polyphenylene oxide, polyacetal, polyimide, Examples include polyamideimide, polyetheretherketone, polyethersulfone, and divinylbenzene polymer. The divinylbenzene polymer may be a divinylbenzene copolymer. Examples of the divinylbenzene copolymer and the like include a divinylbenzene-styrene copolymer and a divinylbenzene-(meth)acrylate copolymer. Since the hardness of the resin particles can be easily controlled within a suitable range, the material of the resin particles preferably contains a polymerizable monomer. More preferably, it is a polymer obtained by polymerizing two or more kinds.
　上記樹脂粒子を、エチレン性不飽和基を有する重合性単量体を重合させて得る場合には、該エチレン性不飽和基を有する重合性単量体としては、非架橋性の単量体と架橋性の単量体とが挙げられる。 When the resin particles are obtained by polymerizing a polymerizable monomer having an ethylenically unsaturated group, the polymerizable monomer having an ethylenically unsaturated group may be a non-crosslinking monomer. and crosslinkable monomers.
　上記非架橋性の単量体としては、スチレン、及びα－メチルスチレン等のスチレン系単量体；（メタ）アクリル酸、マレイン酸、及び無水マレイン酸等のカルボキシル基含有単量体；メチル（メタ）アクリレート、エチル（メタ）アクリレート、プロピル（メタ）アクリレート、ブチル（メタ）アクリレート、２－エチルヘキシル（メタ）アクリレート、ラウリル（メタ）アクリレート、セチル（メタ）アクリレート、ステアリル（メタ）アクリレート、シクロヘキシル（メタ）アクリレート、及びイソボルニル（メタ）アクリレート等のアルキル（メタ）アクリレート化合物；２－ヒドロキシエチル（メタ）アクリレート、グリセロール（メタ）アクリレート、ポリオキシエチレン（メタ）アクリレート、及びグリシジル（メタ）アクリレート等の酸素原子含有（メタ）アクリレート化合物；（メタ）アクリロニトリル等のニトリル含有単量体；メチルビニルエーテル、エチルビニルエーテル、及びプロピルビニルエーテル等のビニルエーテル化合物；酢酸ビニル、酪酸ビニル、ラウリン酸ビニル、及びステアリン酸ビニル等の酸ビニルエステル化合物；エチレン、プロピレン、イソプレン、及びブタジエン等の不飽和炭化水素；トリフルオロメチル（メタ）アクリレート、ペンタフルオロエチル（メタ）アクリレート、塩化ビニル、フッ化ビニル、及びクロルスチレン等のハロゲン含有単量体等が挙げられる。 Examples of the non-crosslinkable monomers include styrene and styrene-based monomers such as α-methylstyrene; carboxyl group-containing monomers such as (meth)acrylic acid, maleic acid, and maleic anhydride; methyl ( meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl ( Alkyl (meth)acrylate compounds such as meth)acrylate and isobornyl (meth)acrylate; 2-hydroxyethyl (meth)acrylate, glycerol (meth)acrylate, polyoxyethylene (meth)acrylate, and glycidyl (meth)acrylate, etc. Oxygen atom-containing (meth)acrylate compounds; nitrile-containing monomers such as (meth)acrylonitrile; vinyl ether compounds such as methyl vinyl ether, ethyl vinyl ether, and propyl vinyl ether; vinyl acetate, vinyl butyrate, vinyl laurate, and vinyl stearate, etc. acid vinyl ester compounds of; unsaturated hydrocarbons such as ethylene, propylene, isoprene, and butadiene; halogens such as trifluoromethyl (meth)acrylate, pentafluoroethyl (meth)acrylate, vinyl chloride, vinyl fluoride, and chlorostyrene A contained monomer etc. are mentioned.
　上記架橋性の単量体としては、テトラメチロールメタンテトラ（メタ）アクリレート、テトラメチロールメタントリ（メタ）アクリレート、テトラメチロールメタンジ（メタ）アクリレート、トリメチロールプロパントリ（メタ）アクリレート、ジペンタエリスリトールヘキサ（メタ）アクリレート、ジペンタエリスリトールペンタ（メタ）アクリレート、ジペンタエリスリトールポリ（メタ）アクリレート、ペンタエリスリトールテトラ（メタ）アクリレート、グリセロールトリ（メタ）アクリレート、グリセロールジ（メタ）アクリレート、（ポリ）エチレングリコールジ（メタ）アクリレート、（ポリ）プロピレングリコールジ（メタ）アクリレート、（ポリ）テトラメチレングリコールジ（メタ）アクリレート、及び１，４－ブタンジオールジ（メタ）アクリレート等の多官能（メタ）アクリレート化合物；トリアリル（イソ）シアヌレート、トリアリルトリメリテート、ジビニルベンゼン、ジアリルフタレート、ジアリルアクリルアミド、ジアリルエーテル、並びに、γ－（メタ）アクリロキシプロピルトリメトキシシラン、トリメトキシシリルスチレン、及びビニルトリメトキシシラン等のシラン含有単量体等が挙げられる。 Examples of the crosslinkable monomer include tetramethylolmethane tetra(meth)acrylate, tetramethylolmethane tri(meth)acrylate, tetramethylolmethane di(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol hexa (meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol poly(meth)acrylate, pentaerythritol tetra(meth)acrylate, glycerol tri(meth)acrylate, glycerol di(meth)acrylate, (poly)ethylene glycol Polyfunctional (meth)acrylate compounds such as di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, (poly)tetramethylene glycol di(meth)acrylate, and 1,4-butanediol di(meth)acrylate triallyl (iso) cyanurate, triallyl trimellitate, divinylbenzene, diallyl phthalate, diallyl acrylamide, diallyl ether, and γ-(meth)acryloxypropyltrimethoxysilane, trimethoxysilylstyrene, vinyltrimethoxysilane, etc. and silane-containing monomers.
　上記エチレン性不飽和基を有する重合性単量体を、公知の方法により重合させることで、上記樹脂粒子を得ることができる。この方法としては、例えば、ラジカル重合開始剤の存在下で懸濁重合する方法、並びに非架橋の種粒子を用いてラジカル重合開始剤とともに単量体を膨潤させて重合する方法等が挙げられる。 The resin particles can be obtained by polymerizing the polymerizable monomer having the ethylenically unsaturated group by a known method. Examples of this method include a method of suspension polymerization in the presence of a radical polymerization initiator, and a method of polymerizing by swelling a monomer together with a radical polymerization initiator using uncrosslinked seed particles.
　上記重合性単量体の単独重合体のガラス転移温度は、好ましくは４０℃以上、より好ましくは５０℃以上、さらに好ましくは８０℃以上であり、好ましくは２５０℃以下、より好ましくは２３０℃以下、さらに好ましくは２００℃以下である。上記重合性単量体の単独重合体のガラス転移温度が上記下限以上及び上記上限以下であると、導電接続時の加熱・加圧によりフラックス含有粒子からフラックスが徐々に漏出する。結果として、導電性粒子の表面及び電極の表面の酸化被膜をより一層効果的に除去することができ、かつ、電極間を電気的に接続した場合に、導通信頼性をより一層効果的に高めることができる。上記樹脂粒子の材料の重合性単量体のうち、重量基準で最も含有量の多い重合性単量体の単独重合体のガラス転移温度が、上記下限以上であることが好ましく、上記上限以下であることが好ましい。 The glass transition temperature of the homopolymer of the polymerizable monomer is preferably 40° C. or higher, more preferably 50° C. or higher, still more preferably 80° C. or higher, and preferably 250° C. or lower, more preferably 230° C. or lower. , and more preferably 200° C. or less. When the glass transition temperature of the homopolymer of the polymerizable monomer is above the lower limit and below the upper limit, the flux gradually leaks out from the flux-containing particles due to heating and pressurization during conductive connection. As a result, the oxide film on the surface of the conductive particles and the surface of the electrode can be removed more effectively, and the reliability of conduction is more effectively improved when the electrodes are electrically connected. be able to. Among the polymerizable monomers of the material of the resin particles, the glass transition temperature of the homopolymer of the polymerizable monomer having the highest content on a weight basis is preferably at least the above lower limit, and at most the above upper limit. Preferably.
　上記フラックスは、特に限定されない。上記フラックスとしては、塩化亜鉛、塩化亜鉛と無機ハロゲン化物との混合物、塩化亜鉛と無機酸との混合物、リン酸、リン酸の誘導体、有機ハロゲン化物、ヒドラジン、アミン化合物、溶融塩、有機酸及び松脂等が挙げられる。上記フラックスは、１種のみが用いられてもよく、２種以上が併用されてもよい。 The above flux is not particularly limited. Examples of the flux include zinc chloride, mixtures of zinc chloride and inorganic halides, mixtures of zinc chloride and inorganic acids, phosphoric acid, phosphoric acid derivatives, organic halides, hydrazine, amine compounds, molten salts, organic acids and pine resin and the like. Only one kind of the above flux may be used, or two or more kinds thereof may be used in combination.
　上記アミン化合物としては、シクロヘキシルアミン、ジシクロヘキシルアミン、ベンジルアミン、ベンズヒドリルアミン、イミダゾール、ベンゾイミダゾール、フェニルイミダゾール、カルボキシベンゾイミダゾール、及びベンゾトリアゾールカルボキシベンゾトリアゾール等が挙げられる。 Examples of the amine compounds include cyclohexylamine, dicyclohexylamine, benzylamine, benzhydrylamine, imidazole, benzimidazole, phenylimidazole, carboxybenzimidazole, benzotriazole, carboxybenzotriazole, and the like.
　上記溶融塩としては、塩化アンモニウム等が挙げられる。 Examples of the molten salt include ammonium chloride.
　導通信頼性をより一層効果的に高める観点からは、上記フラックスは、有機酸、又は松脂であることが好ましく、松脂であることがより好ましい。 From the standpoint of more effectively enhancing conduction reliability, the flux is preferably an organic acid or rosin, more preferably rosin.
　上記有機酸は、カルボキシル基を２個以上有する有機酸であることが好ましい。上記カルボキシル基を２個以上有する有機酸としては、コハク酸、グルタル酸、アジピン酸、ピメリン酸、スベリン酸、アゼライン酸、及びセバシン酸等が挙げられる。 The above organic acid is preferably an organic acid having two or more carboxyl groups. Examples of the organic acid having two or more carboxyl groups include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid.
　上記松脂は、アビエチン酸を主成分とするロジン類である。上記ロジン類としては、アビエチン酸、及びアクリル変性ロジン等が挙げられる。導通信頼性をより一層効果的に高める観点からは、上記ロジン類は、アビエチン酸であることがより好ましい。 The above pine resin is a rosin whose main component is abietic acid. Examples of the rosins include abietic acid and acryl-modified rosins. From the standpoint of more effectively enhancing conduction reliability, the rosin is more preferably abietic acid.
　上記フラックスの融点（活性温度）は、好ましくは１０℃以上、より好ましくは５０℃以上、より好ましくは７０℃以上、さらに好ましくは８０℃以上であり、好ましくは２００℃以下、より好ましくは１９０℃以下、より一層好ましくは１６０℃以下、さらに好ましくは１５０℃以下、さらに一層好ましくは１４０℃以下である。上記フラックスの融点が、上記下限以上及び上記上限以下であると、フラックス効果がより一層効果的に発揮され、電極上に導電性粒子がより一層効率的に配置される。上記フラックスの融点（活性温度）は８０℃以上１９０℃以下であることが好ましく、８０℃以上１４０℃以下であることが特に好ましい。 The melting point (activation temperature) of the flux is preferably 10°C or higher, more preferably 50°C or higher, more preferably 70°C or higher, still more preferably 80°C or higher, and preferably 200°C or lower, more preferably 190°C. Below, it is more preferably 160° C. or lower, still more preferably 150° C. or lower, and even more preferably 140° C. or lower. When the melting point of the flux is equal to or higher than the lower limit and equal to or lower than the upper limit, the flux effect is exhibited more effectively, and the conductive particles are arranged on the electrode even more efficiently. The melting point (activation temperature) of the flux is preferably 80° C. or higher and 190° C. or lower, and particularly preferably 80° C. or higher and 140° C. or lower.
　フラックスの融点（活性温度）が８０℃以上１９０℃以下である上記フラックスとしては、コハク酸（融点１８６℃）、グルタル酸（融点９６℃）、アジピン酸（融点１５２℃）、ピメリン酸（融点１０４℃）、スベリン酸（融点１４２℃）等のジカルボン酸、安息香酸（融点１２２℃）、並びにリンゴ酸（融点１３０℃）等が挙げられる。 Examples of the above-mentioned fluxes having a melting point (activation temperature) of 80° C. or more and 190° C. or less include succinic acid (melting point 186° C.), glutaric acid (melting point 96° C.), adipic acid (melting point 152° C.), pimelic acid (melting point 104° C.). °C), dicarboxylic acids such as suberic acid (melting point 142°C), benzoic acid (melting point 122°C), and malic acid (melting point 130°C).
　また、上記フラックスの沸点は、３００℃以下であることが好ましい。 Also, the boiling point of the flux is preferably 300°C or lower.
　フラックスの効果を高める観点からは、本発明に係る導電性粒子では、上記フラックス含有粒子の粒子径は、好ましくは１００ｎｍ以上、より好ましくは２００ｎｍ以上、さらに好ましくは３５０ｎｍ以上であり、好ましくは８００ｎｍ以下、より好ましくは５００ｎｍ以下、さらに好ましくは４００ｎｍ以下である。 From the viewpoint of enhancing the effect of the flux, in the conductive particles according to the present invention, the particle diameter of the flux-containing particles is preferably 100 nm or more, more preferably 200 nm or more, still more preferably 350 nm or more, and preferably 800 nm or less. , more preferably 500 nm or less, and still more preferably 400 nm or less.
　上記フラックス含有粒子の粒子径は、平均粒子径であり、該平均粒子径は体積平均粒子径を示す。上記フラックス含有粒子の粒子径は粒度分布測定装置等を用いて求められる。 The particle size of the flux-containing particles is the average particle size, and the average particle size indicates the volume average particle size. The particle size of the flux-containing particles is determined using a particle size distribution analyzer or the like.
　上記導電性粒子の粒子径の、上記フラックス含有粒子の粒子径に対する比（導電性粒子の粒子径／フラックス含有粒子の粒子径）は、好ましくは３以上、より好ましくは６以上、さらに好ましくは１６以上であり、好ましくは５００以下、より好ましくは１５０以下、さらに好ましくは１００以下、特に好ましくは７０以下である。上記比（導電性粒子の粒子径／フラックス含有粒子の粒子径）が、上記下限以上及び上記上限以下であると、電極間を電気的に接続した場合に、絶縁信頼性及び導通信頼性をより一層効果的に高めることができる。 The ratio of the particle size of the conductive particles to the particle size of the flux-containing particles (particle size of conductive particles/particle size of flux-containing particles) is preferably 3 or more, more preferably 6 or more, and still more preferably 16. or more, preferably 500 or less, more preferably 150 or less, even more preferably 100 or less, and particularly preferably 70 or less. When the ratio (particle diameter of the conductive particles/particle diameter of the flux-containing particles) is equal to or more than the lower limit and equal to or less than the upper limit, insulation reliability and conduction reliability are improved when the electrodes are electrically connected. can be enhanced more effectively.
　上記導電性粒子本体の粒子径の、上記フラックス含有粒子の粒子径に対する比（導電性粒子本体の粒子径／フラックス含有粒子の粒子径）は、好ましくは３以上、より好ましくは６以上、さらに好ましくは１６以上であり、好ましくは５００以下、より好ましくは１５０以下、さらに好ましくは１００以下、特に好ましくは６０以下である。上記比（導電性粒子本体の粒子径／フラックス含有粒子の粒子径）が、上記下限以上及び上記上限以下であると、電極間を電気的に接続した場合に、絶縁信頼性及び導通信頼性をより一層効果的に高めることができる。 The ratio of the particle diameter of the conductive particle main body to the particle diameter of the flux-containing particle (particle diameter of the conductive particle main body/particle diameter of the flux-containing particle) is preferably 3 or more, more preferably 6 or more, and still more preferably. is 16 or more, preferably 500 or less, more preferably 150 or less, still more preferably 100 or less, and particularly preferably 60 or less. When the above ratio (particle diameter of the conductive particle main body/particle diameter of the flux-containing particles) is equal to or more than the lower limit and equal to or less than the upper limit, insulation reliability and conduction reliability are improved when the electrodes are electrically connected. can be enhanced more effectively.
　本発明の効果をより一層効果的に発揮する観点からは、上記フラックス含有粒子の粒子径の変動係数（ＣＶ値）は、２０％以下であることが好ましい。 From the viewpoint of exhibiting the effect of the present invention more effectively, the coefficient of variation (CV value) of the particle diameter of the flux-containing particles is preferably 20% or less.
　上記変動係数（ＣＶ値）は、以下のようにして測定できる。 The coefficient of variation (CV value) can be measured as follows.
　ＣＶ値（％）＝（ρ／Ｄｎ）×１００
　ρ：フラックス含有粒子の粒子径の標準偏差
　Ｄｎ：フラックス含有粒子の粒子径の平均値 CV value (%) = (ρ/Dn) × 100
ρ: standard deviation of particle size of flux-containing particles Dn: average value of particle size of flux-containing particles
　上記フラックス含有粒子の形状は特に限定されない。上記フラックス含有粒子の形状は、球状であってもよく、球状以外の形状であってもよく、扁平状等であってもよい。本発明の効果をより一層効果的に発揮する観点からは、上記フラックス含有粒子は、球状であることが好ましい。 The shape of the flux-containing particles is not particularly limited. The flux-containing particles may have a spherical shape, a shape other than a spherical shape, or a flat shape. From the viewpoint of exhibiting the effects of the present invention more effectively, the flux-containing particles are preferably spherical.
　本発明の効果をより一層効果的に発揮する観点からは、上記フラックス含有粒子の粒子本体が樹脂粒子である場合に、該樹脂粒子の材料である重合性単量体の単独重合体のガラス転移温度において、上記フラックス含有粒子は、粒子状を維持していることが好ましい。 From the viewpoint of exhibiting the effect of the present invention more effectively, when the particle body of the flux-containing particles is a resin particle, the glass transition of the homopolymer of the polymerizable monomer that is the material of the resin particle At the temperature, the flux-containing particles preferably maintain their particulate form.
　上記フラックス含有粒子は、該フラックス含有粒子に最大試験荷重３．３ｍＮを１０秒かけて負荷したときの圧縮－変位曲線において、破壊点を有しないことが好ましい。この場合には、導電接続時の加熱及び加圧によりフラックス含有粒子からフラックスが徐々に漏出するので、導電性粒子の表面及び電極の表面の酸化被膜をより一層効果的に除去することができ、かつ、電極間を電気的に接続した場合に、導通信頼性をより一層効果的に高めることができる。具体的に、微小圧縮試験機を用いて、円柱（直径５０μｍ、ダイヤモンド製）の平滑圧子端面で、２５℃、最大試験荷重３．３ｍＮを１０秒かけて負荷する条件下でフラックス含有粒子を圧縮する。このときの荷重値（Ｎ）及び圧縮変位（ｍｍ）を測定し、圧縮－変位曲線を作製する。上記微小圧縮試験機として、例えば、エリオニクス社製「ＥＮＴ－ＮＥＸＵＳ」等が用いられる。 The flux-containing particles preferably do not have a breaking point in the compression-displacement curve when a maximum test load of 3.3 mN is applied to the flux-containing particles for 10 seconds. In this case, the flux gradually leaks from the flux-containing particles due to heating and pressurization during conductive connection, so that the oxide film on the surface of the conductive particles and the surface of the electrode can be removed more effectively. In addition, when the electrodes are electrically connected, the reliability of conduction can be improved more effectively. Specifically, using a microcompression tester, the flux-containing particles are compressed at 25° C. with a smooth indenter end face of a cylinder (diameter 50 μm, made of diamond) under the conditions of applying a maximum test load of 3.3 mN for 10 seconds. do. The load value (N) and compression displacement (mm) at this time are measured to prepare a compression-displacement curve. As the microcompression tester, for example, "ENT-NEXUS" manufactured by Elionix Co., Ltd. is used.
　また、本発明の効果をより一層効果的に発揮する観点からは、上記フラックス含有粒子は、フラックスを内包するマイクロカプセルではないことが好ましい。上記フラックス含有粒子における粒子本体は、多孔構造を有する粒子であってもよい。上記多孔構造は、複数の孔（細孔）を有する構造を意味する。 In addition, from the viewpoint of exhibiting the effects of the present invention more effectively, the flux-containing particles are preferably not microcapsules encapsulating flux. The particle body in the flux-containing particles may be particles having a porous structure. The porous structure means a structure having a plurality of pores (pores).
　上記フラックス含有粒子の表面から中心に向かって距離を３等分し、上記フラックス含有粒子を、表面部分と、中心部分と、表面部分と中心部分との間の中間部分との３つの部分に分けたときに、上記フラックス含有粒子はフラックスを、上記表面部分に含んでいてもよく、上記中間部分に含んでいてもよく、上記中心部分に含んでいてもよい。上記フラックス含有粒子はフラックスを、上記表面部分に含むことが好ましく、上記表面部分と上記中間部分とに含むことがより好ましく、上記表面部分と上記中間部分と上記中心部分とに含むことがさらに好ましい。この場合には、導電接続時の加熱及び加圧によりフラックス含有粒子からフラックスが徐々に漏出するので、導電性粒子の表面及び電極の表面の酸化被膜をより一層効果的に除去することができ、かつ、電極間を電気的に接続した場合に、導通信頼性及び絶縁信頼性をより一層効果的に高めることができる。また、上記フラックス含有粒子はフラックスを、上記中間部分と上記中心部分とに含んでいてもよい。 The distance from the surface of the flux-containing particles toward the center is divided into three equal parts, and the flux-containing particles are divided into three parts: a surface part, a center part, and an intermediate part between the surface part and the center part. In this case, the flux-containing particles may contain the flux in the surface portion, the intermediate portion, or the central portion. The flux-containing particles preferably contain flux in the surface portion, more preferably in the surface portion and the intermediate portion, and even more preferably in the surface portion, the intermediate portion, and the central portion. . In this case, the flux gradually leaks from the flux-containing particles due to heating and pressurization during conductive connection, so that the oxide film on the surface of the conductive particles and the surface of the electrode can be removed more effectively. In addition, when the electrodes are electrically connected, the reliability of conduction and the reliability of insulation can be improved more effectively. Also, the flux-containing particles may contain flux in the intermediate portion and the central portion.
　また、導通信頼性及び絶縁信頼性を効果的に高める観点からは、上記フラックス含有粒子は、フラックス含有粒子の表面から中心に向かって厚み１０ｎｍの最表面部分にフラックスを含むことが好ましい。 In addition, from the viewpoint of effectively improving conduction reliability and insulation reliability, the flux-containing particles preferably contain flux in the outermost surface portion having a thickness of 10 nm from the surface to the center of the flux-containing particles.
　導通信頼性を良好にする観点からは、エタノール１００重量部に、上記導電性粒子３重量部を添加した導電性粒子含有液を２０℃及び４０ｋＨｚの条件で５分間超音波処理したときに、下記式（１）により求められるフラックス含有粒子の残存率が、９９％以下であることが好ましい。 From the viewpoint of improving conduction reliability, when a conductive particle-containing liquid obtained by adding 3 parts by weight of the above conductive particles to 100 parts by weight of ethanol was subjected to ultrasonic treatment for 5 minutes at 20 ° C. and 40 kHz, the following It is preferable that the residual rate of the flux-containing particles determined by the formula (1) is 99% or less.
　フラックス含有粒子の残存率（％）＝（超音波処理後のフラックス含有粒子による被覆率／超音波処理前のフラックス含有粒子による被覆率）×１００・・・式（１） Remaining rate of flux-containing particles (%) = (coverage rate of flux-containing particles after ultrasonic treatment/coverage rate of flux-containing particles before ultrasonic treatment) x 100... formula (1)
　上記フラックス含有粒子による被覆率は、上記導電性粒子本体の全表面積１００％中、上記フラックス含有粒子が配置されている部分の合計の面積を意味する。上記フラックス含有粒子による被覆率は、導電性粒子を電子顕微鏡又は光学顕微鏡にて観察し、フラックス含有粒子が配置されている部分の表面積の、導電性粒子本体の投影面積に対する百分率を算出することにより求められる。上記フラックス含有粒子による被覆率は、好ましくは、任意の導電性粒子２０個を走査型電子顕微鏡（ＳＥＭ）にて観察し、フラックス含有粒子が配置されている部分の表面積の、導電性粒子本体の投影面積に対する百分率の平均値を算出することにより求められる。 The coverage rate by the flux-containing particles means the total area of the portion where the flux-containing particles are arranged in 100% of the total surface area of the conductive particle body. The coverage with the flux-containing particles is obtained by observing the conductive particles with an electron microscope or an optical microscope and calculating the percentage of the surface area of the portion where the flux-containing particles are arranged to the projected area of the main body of the conductive particles. Desired. The coverage with the flux-containing particles is preferably determined by observing 20 arbitrary conductive particles with a scanning electron microscope (SEM), and measuring the surface area of the portion where the flux-containing particles are arranged, of the conductive particle body. It is obtained by calculating the average percentage of the projected area.
　導通信頼性を良好にする観点からは、上記フラックス含有粒子の残存率は、好ましくは９０％以下、より好ましくは７０％以下、さらに好ましくは６５％以下、特に好ましくは６０％以下である。上記フラックス含有粒子の残存率の下限は、特に限定されない。上記フラックス含有粒子の残存率は、０％であってもよい。 From the viewpoint of improving conduction reliability, the residual rate of the flux-containing particles is preferably 90% or less, more preferably 70% or less, even more preferably 65% or less, and particularly preferably 60% or less. The lower limit of the residual rate of the flux-containing particles is not particularly limited. The residual rate of the flux-containing particles may be 0%.
　上記フラックス含有粒子の残存率を上記の好ましい範囲にする方法としては、接着性の低い材料で構成された粒子をフラックス含有粒子の粒子本体として使用する方法、及びフラックス含有率が高い粒子をフラックス含有粒子の粒子本体として使用する方法等が挙げられる。 Methods for adjusting the residual rate of the flux-containing particles to the preferred range include a method of using particles made of a material with low adhesiveness as the particle body of the flux-containing particles, and a method of using particles with a high flux content as flux-containing particles. A method of using it as a particle body of particles, and the like.
　上記粒子本体に上記フラックスを含有させる方法（フラックス含有粒子を形成する方法）としては、以下の方法等が挙げられる。フラックスを低濃度で含有した溶媒に粒子本体を分散しフラックス成分を吸着させる方法。フラックス成分を高濃度で含有した有機溶媒を粒子本体にスプレーしフラックスを付着させる方法。粒子作製時の溶媒にフラックスを添加し粒子本体の内部にフラックスを含有させる方法。導通信頼性を良好にする観点からは、上記粒子本体に上記フラックスを含有させる方法は、フラックスを低濃度で含有した溶媒に粒子本体を分散しフラックス成分を吸着させる方法であることが好ましい。 Examples of the method for incorporating the flux into the particle body (method for forming the flux-containing particles) include the following methods. A method in which the particles are dispersed in a solvent containing a low concentration of flux to adsorb the flux components. A method in which an organic solvent containing a high concentration of flux components is sprayed onto the particle body to adhere the flux. A method in which flux is added to the solvent during particle production to contain the flux inside the particle body. From the viewpoint of improving conduction reliability, the method of adding the flux to the particle body is preferably a method of dispersing the particle body in a solvent containing a low concentration of flux to adsorb the flux component.
　上記導電性粒子本体の表面上に上記フラックス含有粒子を配置する方法としては、化学的方法、及び物理的もしくは機械的方法等が挙げられる。上記化学的方法としては、例えば、界面重合法、粒子存在下での懸濁重合法及び乳化重合法等が挙げられる。上記物理的もしくは機械的方法としては、スプレードライ、ハイブリダイゼーション、静電付着法、噴霧法、ディッピング及び真空蒸着による方法等が挙げられる。電極間を電気的に接続した場合に、絶縁信頼性及び導通信頼性をより一層効果的に高める観点からは、上記導電性粒子本体の表面上に上記フラックス含有粒子を配置する方法は、静電付着法であることが好ましい。 Examples of methods for disposing the flux-containing particles on the surface of the conductive particle body include chemical methods and physical or mechanical methods. Examples of the chemical method include an interfacial polymerization method, a suspension polymerization method in the presence of particles, an emulsion polymerization method, and the like. Examples of the physical or mechanical methods include spray drying, hybridization, electrostatic adhesion, atomization, dipping and vacuum deposition. From the viewpoint of more effectively improving the insulation reliability and conduction reliability when the electrodes are electrically connected, the method of arranging the flux-containing particles on the surface of the conductive particle body is an electrostatic Adhesive methods are preferred.
　上記導電部の外表面、及び上記フラックス含有粒子の外表面はそれぞれ、反応性官能基を有する化合物によって被覆されていてもよい。上記導電部の外表面と上記フラックス含有粒子の外表面とは、直接化学結合していなくてもよく、反応性官能基を有する化合物によって間接的に化学結合していてもよい。上記導電部の外表面にカルボキシル基を導入した後、該カルボキシル基がポリエチレンイミン等の高分子電解質を介してフラックス含有粒子の外表面の官能基と化学結合していてもよい。 The outer surface of the conductive portion and the outer surface of the flux-containing particles may each be coated with a compound having a reactive functional group. The outer surface of the conductive portion and the outer surface of the flux-containing particles may not be directly chemically bonded, but may be indirectly chemically bonded by a compound having a reactive functional group. After introducing carboxyl groups into the outer surface of the conductive portion, the carboxyl groups may be chemically bonded to the functional groups on the outer surface of the flux-containing particles via a polymer electrolyte such as polyethyleneimine.
　本発明の効果をより一層効果的に発揮する観点からは、上記導電性粒子１００重量％中、上記フラックス含有粒子の含有量は、好ましくは１重量％以上、より好ましくは１．５重量％以上、より一層好ましくは２重量％以上、さらに好ましくは２．５重量％以上、特に好ましくは３重量％以上である。 From the viewpoint of exhibiting the effects of the present invention more effectively, the content of the flux-containing particles in 100% by weight of the conductive particles is preferably 1% by weight or more, more preferably 1.5% by weight or more. , more preferably 2% by weight or more, still more preferably 2.5% by weight or more, and particularly preferably 3% by weight or more.
　上記導電性粒子１００重量％中、上記フラックス含有粒子中のフラックスの含有量及び上記フラックス膜中のフラックスの含有量の合計は、好ましくは１重量％以上、より好ましくは１．５重量％以上、より一層好ましくは２重量％以上、さらに好ましくは３重量％以上、特に好ましくは１０重量％以上である。フラックスの含有量の合計が上記下限以上であると、本発明の効果をより一層効果的に発揮することができる。 The sum of the flux content in the flux-containing particles and the flux content in the flux film in 100% by weight of the conductive particles is preferably 1% by weight or more, more preferably 1.5% by weight or more, More preferably 2% by weight or more, more preferably 3% by weight or more, and particularly preferably 10% by weight or more. When the total flux content is at least the above lower limit, the effects of the present invention can be exhibited more effectively.
　上記フラックス含有粒子中のフラックスの含有量及び後述するフラックス膜中のフラックスの含有量の合計１００重量％中、上記フラックス含有粒子中のフラックスの含有量は、好ましくは５重量％以上、より好ましくは１０重量％以上、より一層好ましくは１５重量％以上、さらに好ましくは２０重量％以上、特に好ましくは５０重量％以上である。上記フラックス含有粒子中のフラックスの含有量が上記下限以上であると、本発明の効果をより一層効果的に発揮することができる。 The flux content in the flux-containing particles is preferably 5 wt% or more, more preferably 100 wt% in total of the flux content in the flux-containing particles and the flux content in the flux film described later. It is 10% by weight or more, more preferably 15% by weight or more, still more preferably 20% by weight or more, and particularly preferably 50% by weight or more. When the flux content in the flux-containing particles is at least the above lower limit, the effects of the present invention can be exhibited more effectively.
　＜フラックス膜＞
　上記導電性粒子は、フラックス膜を備える。上記フラックス膜は、上記導電性粒子本体の外側に配置されている。上記フラックス膜は、上記導電部の外側に配置されている。上記フラックス膜は、上記導電性粒子本体の表面上に配置されている。上記フラックス膜は、上記導電部の表面上に配置されている。上記フラックス膜は、上記フラックス含有粒子の外側に配置されていてもよく、上記フラックス含有粒子の外側に配置されていなくてもよい。上記フラックス膜は、上記フラックス含有粒子の表面上に配置されていてもよく、上記フラックス含有粒子の表面上に配置されていなくてもよい。 <Flux film>
The conductive particles comprise a flux film. The flux film is arranged outside the conductive particle body. The flux film is arranged outside the conductive portion. The flux film is arranged on the surface of the conductive particle body. The flux film is arranged on the surface of the conductive portion. The flux film may be arranged outside the flux-containing particles, or may not be arranged outside the flux-containing particles. The flux film may be arranged on the surfaces of the flux-containing particles, or may not be arranged on the surfaces of the flux-containing particles.
　上記フラックス膜中のフラックスとしては、上述したフラックスが挙げられる。上記フラックス膜中のフラックスは、上記フラックス含有粒子中のフラックスと同一であってもよく、異なっていてもよい。 The flux in the flux film includes the above-mentioned flux. The flux in the flux film may be the same as or different from the flux in the flux-containing particles.
　上記導電性粒子本体の全表面積１００％中、上記フラックス膜の面積（上記フラックス膜による被覆率）は、好ましくは４０％以上、より好ましくは５０％以上である。上記被覆率の上限は特に限定されない。上記被覆率は９９％以下であってもよい。上記被覆率が、上記下限以上及び上記上限以下であると、導電性粒子の表面及び電極の表面の酸化被膜をより一層効果的に除去することができ、かつ、電極間を電気的に接続した場合に、導通信頼性をより一層効果的に高めることができる。 Within 100% of the total surface area of the conductive particle body, the area of the flux film (coverage by the flux film) is preferably 40% or more, more preferably 50% or more. The upper limit of the coverage rate is not particularly limited. The coverage may be 99% or less. When the coverage is the lower limit or more and the upper limit or less, the oxide film on the surface of the conductive particles and the surface of the electrode can be removed more effectively, and the electrodes are electrically connected. In this case, the conduction reliability can be enhanced more effectively.
　上記フラックス膜の厚みは、好ましくは０．５ｎｍ以上、より好ましくは１ｎｍ以上であり、好ましくは１００ｎｍ以下、より好ましくは５０ｎｍ以下、さらに好ましくは２５ｎｍ以下である。上記フラックス膜の厚みが、上記下限以上及び上記上限以下であると、導通信頼性をより一層効果的に高め、かつ、導電性粒子が硬くなりすぎずに、電極間の接続の際に導電性粒子を十分に変形させることができる。 The thickness of the flux film is preferably 0.5 nm or more, more preferably 1 nm or more, and preferably 100 nm or less, more preferably 50 nm or less, and even more preferably 25 nm or less. When the thickness of the flux film is equal to or more than the lower limit and equal to or less than the upper limit, the conduction reliability is more effectively improved, and the conductive particles do not become too hard, so that the electrodes can be electrically conductive at the time of connection. Particles can be sufficiently deformed.
　上記導電性粒子本体の表面上に上記フラックス膜を配置する方法としては、物理的もしくは機械的方法等が挙げられる。上記物理的もしくは機械的方法としては、スプレードライ、ハイブリダイゼーション、静電付着法、噴霧法、ディッピング及び真空蒸着による方法等が挙げられる。電極間を電気的に接続した場合に、絶縁信頼性及び導通信頼性をより一層効果的に高める観点からは、上記導電性粒子本体の表面上に上記フラックス膜を配置する方法は、ディッピングであることが好ましい。 A physical or mechanical method can be used as a method for arranging the flux film on the surface of the conductive particle body. Examples of the physical or mechanical methods include spray drying, hybridization, electrostatic adhesion, atomization, dipping and vacuum deposition. From the viewpoint of more effectively improving the insulation reliability and conduction reliability when the electrodes are electrically connected, dipping is the method for disposing the flux film on the surface of the conductive particle body. is preferred.
　（導電材料）
　本発明に係る導電材料は、上述した導電性粒子と、バインダー樹脂とを含む。上記導電性粒子は、バインダー樹脂中に分散されて用いられることが好ましく、バインダー樹脂中に分散されて導電材料として用いられることが好ましい。上記導電材料は、異方性導電材料であることが好ましい。上記導電材料は、電極間の電気的な接続に用いられることが好ましい。上記導電材料は回路接続用導電材料であることが好ましい。上記導電材料では、上述した導電性粒子が用いられているので、電極間の絶縁信頼性及び導通信頼性をより一層高めることができる。 (Conductive material)
The conductive material according to the present invention contains the conductive particles described above and a binder resin. The conductive particles are preferably dispersed in a binder resin for use, and preferably dispersed in a binder resin for use as a conductive material. The conductive material is preferably an anisotropic conductive material. The conductive material is preferably used for electrical connection between electrodes. The conductive material is preferably a conductive material for circuit connection. Since the above-described conductive particles are used in the conductive material, the reliability of insulation and reliability of conduction between electrodes can be further improved.
　上記バインダー樹脂は特に限定されない。上記バインダー樹脂として、公知の絶縁性の樹脂が用いられる。上記バインダー樹脂は、熱可塑性成分（熱可塑性化合物）又は硬化性成分を含むことが好ましく、硬化性成分を含むことがより好ましい。上記硬化性成分としては、光硬化性成分及び熱硬化性成分が挙げられる。上記光硬化性成分は、光硬化性化合物及び光重合開始剤を含むことが好ましい。上記熱硬化性成分は、熱硬化性化合物及び熱硬化剤を含むことが好ましい。 The binder resin is not particularly limited. A known insulating resin is used as the binder resin. The binder resin preferably contains a thermoplastic component (thermoplastic compound) or a curable component, and more preferably contains a curable component. Examples of the curable component include photocurable components and thermosetting components. The photocurable component preferably contains a photocurable compound and a photopolymerization initiator. The thermosetting component preferably contains a thermosetting compound and a thermosetting agent.
　上記バインダー樹脂としては、例えば、ビニル樹脂、熱可塑性樹脂、硬化性樹脂、熱可塑性ブロック共重合体及びエラストマー等が挙げられる。上記バインダー樹脂は１種のみが用いられてもよく、２種以上が併用されてもよい。 Examples of the binder resin include vinyl resins, thermoplastic resins, curable resins, thermoplastic block copolymers and elastomers. Only one kind of the binder resin may be used, or two or more kinds thereof may be used in combination.
　上記ビニル樹脂としては、例えば、酢酸ビニル樹脂、アクリル樹脂及びスチレン樹脂等が挙げられる。上記熱可塑性樹脂としては、例えば、ポリオレフィン樹脂、エチレン－酢酸ビニル共重合体及びポリアミド樹脂等が挙げられる。上記硬化性樹脂としては、例えば、エポキシ樹脂、ウレタン樹脂、ポリイミド樹脂及び不飽和ポリエステル樹脂等が挙げられる。なお、上記硬化性樹脂は、常温硬化型樹脂、熱硬化型樹脂、光硬化型樹脂又は湿気硬化型樹脂であってもよい。上記硬化性樹脂は、硬化剤と併用されてもよい。上記熱可塑性ブロック共重合体としては、例えば、スチレン－ブタジエン－スチレンブロック共重合体、スチレン－イソプレン－スチレンブロック共重合体、スチレン－ブタジエン－スチレンブロック共重合体の水素添加物、及びスチレン－イソプレン－スチレンブロック共重合体の水素添加物等が挙げられる。上記エラストマーとしては、例えば、スチレン－ブタジエン共重合ゴム、及びアクリロニトリル－スチレンブロック共重合ゴム等が挙げられる。 Examples of the vinyl resin include vinyl acetate resin, acrylic resin and styrene resin. Examples of the thermoplastic resins include polyolefin resins, ethylene-vinyl acetate copolymers and polyamide resins. Examples of the curable resin include epoxy resin, urethane resin, polyimide resin and unsaturated polyester resin. The curable resin may be a room temperature curable resin, a thermosetting resin, a photocurable resin, or a moisture curable resin. The curable resin may be used in combination with a curing agent. Examples of the thermoplastic block copolymers include styrene-butadiene-styrene block copolymers, styrene-isoprene-styrene block copolymers, hydrogenated products of styrene-butadiene-styrene block copolymers, and styrene-isoprene. - hydrogenated products of styrene block copolymers; Examples of the elastomer include styrene-butadiene copolymer rubber and acrylonitrile-styrene block copolymer rubber.
　上記導電材料は、上記導電性粒子及び上記バインダー樹脂の他に、例えば、充填剤、増量剤、軟化剤、可塑剤、重合触媒、硬化触媒、着色剤、酸化防止剤、熱安定剤、光安定剤、紫外線吸収剤、滑剤、帯電防止剤及び難燃剤等の各種添加剤を含んでいてもよい。 In addition to the conductive particles and the binder resin, the conductive material includes, for example, a filler, an extender, a softener, a plasticizer, a polymerization catalyst, a curing catalyst, a coloring agent, an antioxidant, a heat stabilizer, and a light stabilizer. It may contain various additives such as agents, UV absorbers, lubricants, antistatic agents and flame retardants.
　上記バインダー樹脂中に上記導電性粒子を分散させる方法は、従来公知の分散方法を用いることができ、特に限定されない。上記バインダー樹脂中に上記導電性粒子を分散させる方法としては、例えば、以下の方法等が挙げられる。上記バインダー樹脂中に上記導電性粒子を添加した後、プラネタリーミキサー等で混練して分散させる方法。上記導電性粒子を水又は有機溶剤中にホモジナイザー等を用いて均一に分散させた後、上記バインダー樹脂中に添加し、プラネタリーミキサー等で混練して分散させる方法。上記バインダー樹脂を水又は有機溶剤等で希釈した後、上記導電性粒子を添加し、プラネタリーミキサー等で混練して分散させる方法。 The method for dispersing the conductive particles in the binder resin is not particularly limited, and a conventionally known dispersing method can be used. Examples of the method for dispersing the conductive particles in the binder resin include the following methods. A method of adding the conductive particles to the binder resin and then kneading and dispersing the mixture with a planetary mixer or the like. A method in which the conductive particles are uniformly dispersed in water or an organic solvent using a homogenizer or the like, then added to the binder resin, kneaded with a planetary mixer or the like, and dispersed. A method of diluting the binder resin with water, an organic solvent, or the like, adding the conductive particles, and kneading and dispersing the mixture with a planetary mixer or the like.
　上記導電材料の２５℃での粘度（η２５）は、好ましくは３０Ｐａ・ｓ以上、より好ましくは５０Ｐａ・ｓ以上であり、好ましくは４００Ｐａ・ｓ以下、より好ましくは３００Ｐａ・ｓ以下である。上記導電材料の２５℃での粘度が、上記下限以上及び上記上限以下であると、電極間の絶縁信頼性をより一層効果的に高めることができ、電極間の導通信頼性をより一層効果的に高めることができる。上記粘度（η２５）は、配合成分の種類及び配合量により適宜調整することができる。 The viscosity (η25) of the conductive material at 25°C is preferably 30 Pa·s or more, more preferably 50 Pa·s or more, and preferably 400 Pa·s or less, more preferably 300 Pa·s or less. When the viscosity of the conductive material at 25 ° C. is at least the lower limit and at most the upper limit, the insulation reliability between the electrodes can be more effectively improved, and the conduction reliability between the electrodes can be more effectively improved. can be increased to The viscosity (η25) can be appropriately adjusted depending on the types and amounts of ingredients to be blended.
　上記粘度（η２５）は、例えば、Ｅ型粘度計（東機産業社製「ＴＶＥ２２Ｌ」）等を用いて、２５℃及び５ｒｐｍの条件で測定することができる。 The viscosity (η25) can be measured, for example, using an E-type viscometer ("TVE22L" manufactured by Toki Sangyo Co., Ltd.) under conditions of 25°C and 5 rpm.
　本発明に係る導電材料は、導電ペースト及び導電フィルム等として使用され得る。本発明に係る導電材料が、導電フィルムである場合には、導電性粒子を含む導電フィルムに、導電性粒子を含まないフィルムが積層されていてもよい。上記導電ペーストは、異方性導電ペーストであることが好ましい。上記導電フィルムは、異方性導電フィルムであることが好ましい。 The conductive material according to the present invention can be used as a conductive paste, a conductive film, and the like. When the conductive material according to the present invention is a conductive film, a film containing no conductive particles may be laminated on a conductive film containing conductive particles. The conductive paste is preferably an anisotropic conductive paste. The conductive film is preferably an anisotropic conductive film.
　上記導電材料１００重量％中、上記バインダー樹脂の含有量は、好ましくは１０重量％以上、より好ましくは３０重量％以上、さらに好ましくは５０重量％以上、特に好ましくは７０重量％以上であり、好ましくは９９．９９重量％以下、より好ましくは９９．９重量％以下である。上記バインダー樹脂の含有量が、上記下限以上及び上記上限以下であると、電極間に導電性粒子が効率的に配置され、導電材料により接続された接続対象部材の接続信頼性をより一層高めることができる。 The content of the binder resin in 100% by weight of the conductive material is preferably 10% by weight or more, more preferably 30% by weight or more, still more preferably 50% by weight or more, and particularly preferably 70% by weight or more. is 99.99% by weight or less, more preferably 99.9% by weight or less. When the content of the binder resin is the lower limit or more and the upper limit or less, the conductive particles are efficiently arranged between the electrodes, and the connection reliability of the connection target members connected by the conductive material is further improved. can be done.
　上記導電材料１００重量％中、上記導電性粒子の含有量は、好ましくは０．０１重量％以上、より好ましくは０．１重量％以上であり、好ましくは８０重量％以下、より好ましくは６０重量％以下、さらに好ましくは４０重量％以下、特に好ましくは２０重量％以下、最も好ましくは１０重量％以下である。上記導電性粒子の含有量が、上記下限以上及び上記上限以下であると、電極間の導通信頼性及び絶縁信頼性をより一層高めることができる。 The content of the conductive particles in 100% by weight of the conductive material is preferably 0.01% by weight or more, more preferably 0.1% by weight or more, and preferably 80% by weight or less, more preferably 60% by weight. %, more preferably 40% by weight or less, particularly preferably 20% by weight or less, and most preferably 10% by weight or less. When the content of the conductive particles is equal to or more than the lower limit and equal to or less than the upper limit, reliability of electrical connection and reliability of insulation between electrodes can be further enhanced.
　（接続構造体）
　本発明に係る接続構造体は、第１の電極を表面に有する第１の接続対象部材と、第２の電極を表面に有する第２の接続対象部材と、上記第１の接続対象部材と、上記第２の接続対象部材を接続している接続部とを備える。本発明に係る接続構造体では、上記接続部の材料が、上述した導電性粒子を含む。本発明に係る接続構造体では、上記第１の電極と上記第２の電極とが、上記導電性粒子本体により電気的に接続されている。上記接続部の材料は、導電性粒子であるか、又は上記導電性粒子とバインダー樹脂とを含む導電材料であることが好ましい。 (connection structure)
A connection structure according to the present invention includes a first connection object member having a first electrode on the surface, a second connection object member having a second electrode on the surface, the first connection object member, and a connecting portion connecting the second connection target member. In the bonded structure according to the present invention, the material of the connecting portion contains the above-described conductive particles. In the connection structure according to the present invention, the first electrode and the second electrode are electrically connected by the conductive particle body. The material of the connecting portion is preferably conductive particles or a conductive material containing the conductive particles and a binder resin.
　上記接続構造体は、上記第１の接続対象部材と上記第２の接続対象部材との間に、上記導電性粒子又は上記導電材料を配置する工程と、熱圧着することにより、導電接続する工程とを経て、得ることができる。上記熱圧着時に、上記フラックス含有粒子が上記導電性粒子から脱離することが好ましい。特に、導電性粒子本体と電極との間の上記フラックス含有粒子が上記導電性粒子から脱離することが好ましい。 The connection structure includes a step of disposing the conductive particles or the conductive material between the first member to be connected and the second member to be connected, and a step of electrically connecting by thermocompression bonding. can be obtained through It is preferable that the flux-containing particles are detached from the conductive particles during the thermocompression bonding. In particular, it is preferable that the flux-containing particles between the conductive particle body and the electrode are detached from the conductive particles.
　図５は、本発明の第１の実施形態に係る導電性粒子を用いた接続構造体を模式的に示す断面図である。 FIG. 5 is a cross-sectional view schematically showing a connection structure using conductive particles according to the first embodiment of the present invention.
　図５に示す接続構造体８１は、第１の接続対象部材８２と、第２の接続対象部材８３と、第１の接続対象部材８２及び第２の接続対象部材８３を接続している接続部８４とを備える。接続部８４は、導電性粒子１を含む導電材料により形成されている。接続部８４は、導電性粒子１を複数含む導電材料を硬化させることにより形成されていることが好ましい。なお、図５では、導電性粒子１は、図示の便宜上、略図的に示されている。導電性粒子１に代えて、導電性粒子１Ａ、導電性粒子１Ｂ、又は導電性粒子１Ｃが用いられてもよい。 A connection structure 81 shown in FIG. 5 includes a first connection target member 82, a second connection target member 83, and a connection portion that connects the first connection target member 82 and the second connection target member 83. 84. The connecting portion 84 is made of a conductive material containing the conductive particles 1 . The connecting portion 84 is preferably formed by curing a conductive material containing a plurality of conductive particles 1 . In addition, in FIG. 5, the conductive particles 1 are schematically shown for convenience of illustration. Instead of the conductive particles 1, conductive particles 1A, conductive particles 1B, or conductive particles 1C may be used.
　第１の接続対象部材８２は表面（上面）に、複数の第１の電極８２ａを有する。第２の接続対象部材８３は表面（下面）に、複数の第２の電極８３ａを有する。第１の電極８２ａと第２の電極８３ａとが、１つ又は複数の導電性粒子１における導電性粒子本体１１により電気的に接続されている。従って、第１の接続対象部材８２及び第２の接続対象部材８３が導電性粒子１における導電性粒子本体１１により電気的に接続されている。 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 surface (lower surface). The first electrode 82a and the second electrode 83a are electrically connected by the conductive particle body 11 of the one or more conductive particles 1 . Therefore, the first connection object member 82 and the second connection object member 83 are electrically connected by the conductive particle body 11 of the conductive particle 1 .
　上記接続構造体の製造方法は特に限定されない。接続構造体の製造方法の一例としては、第１の接続対象部材と第２の接続対象部材との間に上記導電材料を配置し、積層体を得た後、該積層体を加熱及び加圧する方法等が挙げられる。上記熱圧着の圧力は好ましくは４０ＭＰａ以上、より好ましくは６０ＭＰａ以上であり、好ましくは９０ＭＰａ以下、より好ましくは７０ＭＰａ以下である。上記熱圧着の加熱の温度は、好ましくは８０℃以上、より好ましくは１００℃以上であり、好ましくは１４０℃以下、より好ましくは１２０℃以下である。上記熱圧着の圧力及び加熱の温度が、上記下限以上及び上記上限以下であると、導電接続時に導電性粒子の表面から上記フラックス含有粒子及び上記フラックス膜を容易に排除することができ、電極間の導通信頼性をより一層高めることができる。また、上記フラックス含有粒子が脱離する際に、上記フラックス含有粒子からフラックスが徐々に漏出するので、導電性粒子の表面及び電極の表面の酸化被膜をより一層効果的に除去することができ、かつ、電極間を電気的に接続した場合に、導通信頼性をより一層効果的に高めることができる。さらに、導電接続後にも上記フラックス含有粒子からフラックスが徐々に漏出するので、導電接続後の導電性粒子の表面及び電極の表面の酸化被膜も効果的に除去することができ、かつ、電極間を電気的に接続した場合に、導通信頼性をより一層効果的に高めることができる。 The manufacturing method of the connection structure is not particularly limited. As an example of a method for manufacturing a connected structure, the conductive material is arranged between a first member to be connected and a second member to be connected to obtain a laminate, and then the laminate is heated and pressurized. methods and the like. The pressure of the thermocompression bonding is preferably 40 MPa or higher, more preferably 60 MPa or higher, and preferably 90 MPa or lower, more preferably 70 MPa or lower. The heating temperature for the thermocompression bonding is preferably 80° C. or higher, more preferably 100° C. or higher, and preferably 140° C. or lower, more preferably 120° C. or lower. When the pressure and heating temperature of the thermocompression bonding are equal to or higher than the lower limit and equal to or lower than the upper limit, the flux-containing particles and the flux film can be easily removed from the surface of the conductive particles at the time of conductive connection. can further improve the reliability of electrical continuity. In addition, since the flux gradually leaks from the flux-containing particles when the flux-containing particles are desorbed, the oxide film on the surface of the conductive particles and the surface of the electrode can be removed more effectively. In addition, when the electrodes are electrically connected, the reliability of conduction can be improved more effectively. Furthermore, since the flux gradually leaks from the flux-containing particles even after the conductive connection, the oxide film on the surfaces of the conductive particles and the electrodes after the conductive connection can be effectively removed, and the electrodes are separated. When electrically connected, the conduction reliability can be enhanced more effectively.
　上記積層体を加熱及び加圧する際に、上記導電性粒子と、上記第１の電極及び上記第２の電極との間に存在している上記フラックス含有粒子及び上記フラックス膜を排除することができる。例えば、上記加熱及び加圧の際には、上記導電性粒子と、上記第１の電極及び上記第２の電極との間に存在している上記フラックス含有粒子及び上記フラックス膜が、上記導電性粒子の表面から脱離する。なお、上記加熱及び加圧の際には、上記導電性粒子の表面から一部の上記フラックス含有粒子及びフラックス膜が脱離して、上記導電性粒子本体の表面（導電部）が部分的に露出することがある。上記導電性粒子本体の表面（導電部）が露出した部分が、上記第１の電極及び上記第２の電極に接触することにより、上記導電性粒子本体を介して第１の電極と第２の電極とを電気的に接続することができる。 When heating and pressurizing the laminate, the flux-containing particles and the flux film existing between the conductive particles and the first electrode and the second electrode can be eliminated. . For example, during the heating and pressurization, the flux-containing particles and the flux film existing between the conductive particles and the first electrode and the second electrode become conductive. It desorbs from the surface of the particle. During the heating and pressurization, part of the flux-containing particles and the flux film are detached from the surfaces of the conductive particles, and the surfaces (conductive portions) of the conductive particles are partially exposed. I have something to do. The portion where the surface (conductive portion) of the conductive particle body is exposed contacts the first electrode and the second electrode, so that the first electrode and the second electrode are connected via the conductive particle body. The electrodes can be electrically connected.
　上記第１の接続対象部材及び第２の接続対象部材は、特に限定されない。上記第１の接続対象部材及び第２の接続対象部材としては、具体的には、半導体チップ、半導体パッケージ、ＬＥＤチップ、ＬＥＤパッケージ、コンデンサ及びダイオード等の電子部品、並びに樹脂フィルム、プリント基板、フレキシブルプリント基板、フレキシブルフラットケーブル、リジッドフレキシブル基板、ガラスエポキシ基板及びガラス基板等の回路基板等の電子部品等が挙げられる。上記第１の接続対象部材及び第２の接続対象部材は、電子部品であることが好ましい。 The first member to be connected and the second member to be connected are not particularly limited. Specifically, the first connection target member and the second connection target member include electronic components such as semiconductor chips, semiconductor packages, LED chips, LED packages, capacitors and diodes, as well as resin films, printed circuit boards, flexible Examples include electronic components such as circuit boards such as printed boards, flexible flat cables, rigid flexible boards, glass epoxy boards and glass boards. The first member to be connected and the second member to be connected are preferably electronic components.
　上記接続対象部材に設けられている電極としては、金電極、ニッケル電極、錫電極、アルミニウム電極、銅電極、モリブデン電極、銀電極、ＳＵＳ電極、及びタングステン電極等の金属電極が挙げられる。上記接続対象部材がフレキシブルプリント基板である場合には、上記電極は金電極、ニッケル電極、錫電極、銀電極又は銅電極であることが好ましい。上記接続対象部材がガラス基板である場合には、上記電極はアルミニウム電極、銅電極、モリブデン電極、銀電極又はタングステン電極であることが好ましい。なお、上記電極がアルミニウム電極である場合には、アルミニウムのみで形成された電極であってもよく、金属酸化物層の表面にアルミニウム層が積層された電極であってもよい。上記金属酸化物層の材料としては、３価の金属元素がドープされた酸化インジウム及び３価の金属元素がドープされた酸化亜鉛等が挙げられる。上記３価の金属元素としては、Ｓｎ、Ａｌ及びＧａ等が挙げられる。 Examples of the electrodes provided on the connection target members include metal electrodes such as gold electrodes, nickel electrodes, tin electrodes, aluminum electrodes, copper electrodes, molybdenum electrodes, silver electrodes, SUS electrodes, and tungsten electrodes. When the member to be connected is a flexible printed circuit board, the electrode is preferably a gold electrode, a nickel electrode, a tin electrode, a silver electrode or a copper electrode. When the member to be connected is a glass substrate, the electrode is preferably an aluminum electrode, a copper electrode, a molybdenum electrode, a silver electrode, or a tungsten electrode. When the electrode is an aluminum electrode, it may be an electrode made of only aluminum, or an electrode in which an aluminum layer is laminated on the surface of a metal oxide layer. Examples of materials for 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 elements include Sn, Al and Ga.
　以下、実施例及び比較例を挙げて、本発明を具体的に説明する。本発明は、以下の実施例のみに限定されない。 The present invention will be specifically described below with reference to examples and comparative examples. The invention is not limited only to the following examples.
　以下の材料を用意した。 "I prepared the following materials."
　フラックス：
　ロジン系フラックス（荒川化学工業社製「ＫＲ－６１２」、軟化点：８２℃）
　アジピン酸ベンジルアミン塩（融点：１７１℃） flux:
Rosin-based flux ("KR-612" manufactured by Arakawa Chemical Industries, softening point: 82 ° C.)
Adipate benzylamine salt (melting point: 171°C)
　（実施例１）
　（１）導電性粒子本体の作製
　（基材粒子の作製）
　基材粒子として、テトラメチロールメタンテトラアクリレートとジビニルベンゼンとの共重合体により形成された樹脂粒子（平均粒子径２０μｍ）を用意した。パラジウム触媒液を５重量％含むアルカリ溶液１００重量部に、基材粒子１０重量部を、超音波分散器を用いて分散させた後、溶液をろ過することにより、基材粒子を取り出した。次いで、ジメチルアミンボランを１重量％含む溶液１００重量部に基材粒子を添加し、基材粒子の表面を活性化させた。表面が活性化された基材粒子を十分に水洗した後、蒸留水５００重量部に加え、分散させることにより、分散液（Ａ）を得た。次に、分散液（Ａ）に、ニッケル粒子スラリー（平均粒子径１００ｎｍ）１ｇを３分間かけて添加し、芯物質が付着された基材粒子を含む懸濁液（Ａ）を得た。 (Example 1)
(1) Production of conductive particle body (production of substrate particles)
Resin particles (average particle diameter: 20 μm) formed from a copolymer of tetramethylolmethane tetraacrylate and divinylbenzene were prepared as substrate particles. After dispersing 10 parts by weight of the base particles in 100 parts by weight of an alkaline solution containing 5% by weight of the palladium catalyst solution using an ultrasonic disperser, the solution was filtered to obtain the base particles. Next, the substrate particles were added to 100 parts by weight of a solution containing 1% by weight of dimethylamine borane to activate the surfaces of the substrate particles. After thoroughly washing the surface-activated substrate particles with water, they were added to 500 parts by weight of distilled water and dispersed to obtain a dispersion liquid (A). Next, 1 g of a nickel particle slurry (average particle size: 100 nm) was added to the dispersion (A) over 3 minutes to obtain a suspension (A) containing substrate particles to which the core substance was attached.
　（導電部の形成）
　硫酸ニッケル０．３５ｍｏｌ／Ｌ、ジメチルアミンボラン１．３８ｍｏｌ／Ｌ及びクエン酸ナトリウム０．５ｍｏｌ／Ｌを含むニッケルめっき液（ｐＨ８．５）を用意した。懸濁液（Ａ）を７０℃にて撹拌しながら、ニッケルめっき液を懸濁液（Ａ）に徐々に滴下し、無電解ニッケルめっきを行った。その後、ろ過することにより、粒子を取り出し、水洗し、乾燥させて、基材粒子の表面上に第１の導電部（ニッケル－ボロン層）を形成した。次に、硫酸錫１５ｇ／Ｌ、エチレンジアミン四酢酸４５ｇ／Ｌ及びホスフィン酸１．５ｇ／Ｌを含む混合液を、水酸化ナトリウムにてｐＨ８．５に調整した錫めっき液を用意した。また、水素化ホウ素ナトリウム５ｇ／Ｌを含む溶液を、水酸化ナトリウムにてｐＨ１０．０に調整した還元液を用意した。錫めっき液を、第１の導電部を有する基材粒子に徐々に滴下し、無電解錫めっきを行った後、還元液により還元させた。その後、ろ過することにより、粒子を取り出し、水洗し、乾燥させて、第１の導電部（ニッケル－ボロン層、厚み０．２μｍ）及び第２の導電部（錫層、厚み０．２５μｍ）を有する導電性粒子本体を得た。 (Formation of conductive portion)
A nickel plating solution (pH 8.5) containing 0.35 mol/L nickel sulfate, 1.38 mol/L dimethylamine borane, and 0.5 mol/L sodium citrate was prepared. While the suspension (A) was stirred at 70° C., the nickel plating solution was gradually dropped into the suspension (A) to perform electroless nickel plating. After that, the particles were taken out by filtration, washed with water, and dried to form a first conductive portion (nickel-boron layer) on the surface of the substrate particles. Next, a tin plating solution was prepared by adjusting a mixed solution containing 15 g/L of tin sulfate, 45 g/L of ethylenediaminetetraacetic acid, and 1.5 g/L of phosphinic acid to pH 8.5 with sodium hydroxide. A reducing solution was prepared by adjusting the pH of a solution containing 5 g/L of sodium borohydride to 10.0 with sodium hydroxide. The tin plating solution was gradually dripped onto the substrate particles having the first conductive portions to carry out electroless tin plating, and then reduced with a reducing solution. After that, the particles are taken out by filtering, washed with water, and dried to form the first conductive portion (nickel-boron layer, thickness 0.2 μm) and the second conductive portion (tin layer, thickness 0.25 μm). A conductive particle body having
　（２）導電性粒子の作製
　（フラックス含有粒子における粒子本体（樹脂粒子）の作製）
　４つ口セパラブルカバー、撹拌翼、三方コック、冷却管及び温度プローブを取り付けた２０００ｍＬセパラブルフラスコに、下記の組成物を入れた後、固形分が１０重量％となるように蒸留水を添加して、１２０ｒｐｍで撹拌し、窒素雰囲気下５０℃で５時間重合を行った。上記組成物は、メタクリル酸メチル１０８０ｍｍｏｌ、ジメタクリル酸エチレングリコール１０ｍｍｏｌ、４－（メタクリロイルオキシ）フェニルジメチルスルホニウムメチルスルフェート０．５ｍｍｏｌ、及び２，２’－アゾビス｛２－［Ｎ－（２－カルボキシエチル）アミジノ］プロパン｝０．５ｍｍｏｌを含む。反応終了後、凍結乾燥して、４－（メタクリロイルオキシ）フェニルジメチルスルホニウムメチルスルフェートに由来するスルホン基を表面に有する樹脂粒子（粒子径３６０ｎｍ）を得た。 (2) Preparation of conductive particles (Preparation of particle bodies (resin particles) in flux-containing particles)
After adding the following composition to a 2000 mL separable flask equipped with a 4-neck separable cover, a stirring blade, a three-way cock, a cooling tube and a temperature probe, distilled water is added so that the solid content becomes 10% by weight. Then, the mixture was stirred at 120 rpm and polymerized at 50° C. for 5 hours under a nitrogen atmosphere. The above composition contains 1080 mmol of methyl methacrylate, 10 mmol of ethylene glycol dimethacrylate, 0.5 mmol of 4-(methacryloyloxy)phenyldimethylsulfonium methylsulfate, and 2,2′-azobis{2-[N-(2-carboxy ethyl)amidino]propane}0.5 mmol. After completion of the reaction, the reaction mixture was lyophilized to obtain resin particles (particle size: 360 nm) having sulfone groups derived from 4-(methacryloyloxy)phenyldimethylsulfonium methylsulfate on their surfaces.
　（フラックス含有粒子及びフラックス膜を備える導電性粒子の作製）
　得られた樹脂粒子を超音波照射下で蒸留水に分散させ、樹脂粒子の１０重量％水分散液（Ｂ）を得た。（１）で得られた導電性粒子本体１０ｇを蒸留水５００ｍＬに分散させた後、分散液（Ｂ）１ｇを添加し、室温で８時間撹拌した。３μｍのメッシュフィルターでろ過した後、メタノールで洗浄、乾燥させて、粒子本体（樹脂粒子）付き導電性粒子を得た。得られた粒子本体付き導電性粒子を、エタノール２００ｍＬに分散させ、分散液（Ｃ）を得た。その後、分散液（Ｃ）と、ロジン系フラックス０．５ｇを溶解させたエタノール３００ｍＬとを混合し、温度５０℃で、超音波分散にて１０分撹拌した。３μｍのメッシュフィルターでろ過した後、乾燥させることにより、フラックス含有粒子及びフラックス膜を備える導電性粒子を得た。 (Preparation of Conductive Particles Equipped with Flux-Containing Particles and Flux Film)
The obtained resin particles were dispersed in distilled water under ultrasonic irradiation to obtain a 10% by weight aqueous dispersion (B) of resin particles. After dispersing 10 g of the conductive particle main body obtained in (1) in 500 mL of distilled water, 1 g of dispersion liquid (B) was added and stirred at room temperature for 8 hours. After filtration through a 3 μm mesh filter, the particles were washed with methanol and dried to obtain conductive particles with particle bodies (resin particles). The obtained conductive particles with particle bodies were dispersed in 200 mL of ethanol to obtain a dispersion (C). Thereafter, the dispersion liquid (C) was mixed with 300 mL of ethanol in which 0.5 g of a rosin-based flux was dissolved, and the mixture was stirred for 10 minutes by ultrasonic dispersion at a temperature of 50°C. After filtration through a 3 μm mesh filter, the particles were dried to obtain conductive particles having flux-containing particles and a flux film.
　（３）導電材料（異方性導電ペースト）の作製
　得られた導電性粒子７重量部と、ビスフェノールＡ型フェノキシ樹脂２５重量部と、フルオレン型エポキシ樹脂４重量部と、フェノールノボラック型エポキシ樹脂３０重量部と、ＳＩ－６０Ｌ（三新化学工業社製）とを配合して、３分間脱泡及び撹拌することで、導電材料（異方性導電ペースト）を得た。 (3) Preparation of conductive material (anisotropic conductive paste) 7 parts by weight of the obtained conductive particles, 25 parts by weight of bisphenol A type phenoxy resin, 4 parts by weight of fluorene type epoxy resin, and 30 parts by weight of phenol novolak type epoxy resin. A conductive material (anisotropic conductive paste) was obtained by blending parts by weight and SI-60L (manufactured by Sanshin Chemical Industry Co., Ltd.), followed by defoaming and stirring for 3 minutes.
　（４）接続構造体の作製
　Ｌ／Ｓが２００μｍ／２００μｍであるＡｕ電極パターン（第１の電極、電極：Ｃｕ上にＮｉ／Ａｕ薄膜）が上面に形成されたフレキシブルプリント基板を用意した。また、Ｌ／Ｓが２００μｍ／２００μｍであるＡｕ電極パターン（第２の電極、電極：Ｃｕ上にＮｉ／Ａｕ薄膜）が下面に形成されたプリント基板を用意した。 (4) Fabrication of Connection Structure A flexible printed circuit board was prepared on which an Au electrode pattern (first electrode, electrode: Ni/Au thin film on Cu) with L/S of 200 μm/200 μm was formed on the upper surface. In addition, a printed circuit board having an Au electrode pattern (second electrode, electrode: Ni/Au thin film on Cu) with L/S of 200 μm/200 μm formed on the lower surface was prepared.
　上記プリント基板上に、得られた異方性導電ペーストを厚さ３０μｍとなるように塗工し、異方性導電ペースト層を形成した。次に、異方性導電ペースト層上に上記フレキシブルプリント基板を、電極同士が対向するように積層した。その後、異方性導電ペースト層の温度が１００℃となるようにヘッドの温度を調整しながら、半導体チップの上面に加圧加熱ヘッドを載せ、６０ＭＰａの圧力をかけて異方性導電ペースト層を１００℃で硬化させ、接続構造体を得た。 The obtained anisotropic conductive paste was applied onto the printed circuit board so as to have a thickness of 30 μm to form an anisotropic conductive paste layer. Next, the flexible printed circuit board was laminated on the anisotropic conductive paste layer so that the electrodes faced each other. After that, while adjusting the temperature of the head so that the temperature of the anisotropic conductive paste layer becomes 100° C., a pressure heating head is placed on the upper surface of the semiconductor chip, and a pressure of 60 MPa is applied to the anisotropic conductive paste layer. It was cured at 100° C. to obtain a connected structure.
　（実施例２）
　フラックス含有粒子における粒子本体の作製の際に、組成物中のメタクリル酸メチルの配合量を１０８０ｍｍｏｌから１８０ｍｍｏｌに変更し、さらに組成物中にメタクリル酸グリシジル９００ｍｍｏｌを添加した。上記の変更以外は、実施例１と同様にして、導電性粒子、導電材料及び接続構造体を得た。 (Example 2)
When producing the particle bodies of the flux-containing particles, the amount of methyl methacrylate in the composition was changed from 1080 mmol to 180 mmol, and 900 mmol of glycidyl methacrylate was added to the composition. Conductive particles, a conductive material and a connection structure were obtained in the same manner as in Example 1 except for the above changes.
　（実施例３）
　フラックス含有粒子における粒子本体の作製の際に、組成物中にメタクリル酸メチル１０８０ｍｍоｌの代りに、ポリスチレン８４０ｍｍｏｌ及びメタクリル酸ラウリル２４０ｍｍｏｌを添加した。上記の変更以外は、実施例１と同様にして、導電性粒子、導電材料及び接続構造体を得た。 (Example 3)
During the preparation of the particle body in the flux-containing particles, 840 mmol of polystyrene and 240 mmol of lauryl methacrylate were added to the composition instead of 1080 mmol of methyl methacrylate. Conductive particles, a conductive material and a connection structure were obtained in the same manner as in Example 1 except for the above changes.
　（実施例４）
　フラックス含有粒子における粒子本体の作製の際に、組成物中のメタクリル酸メチルの配合量を１０８０ｍｍｏｌから５４０ｍｍｏｌに変更し、さらに組成物中にメタクリル酸グリシジル５４０ｍｍｏｌを添加した。上記の変更以外は、実施例１と同様にして、導電性粒子、導電材料及び接続構造体を得た。 (Example 4)
When producing the particle bodies of the flux-containing particles, the blending amount of methyl methacrylate in the composition was changed from 1080 mmol to 540 mmol, and 540 mmol of glycidyl methacrylate was added to the composition. Conductive particles, a conductive material and a connection structure were obtained in the same manner as in Example 1 except for the above changes.
　（実施例５）
　フラックス含有粒子及びフラックス膜におけるフラックスを、アジピン酸ベンジルアミン塩に変更したこと以外は、実施例１と同様にして、導電性粒子、導電材料及び接続構造体を得た。 (Example 5)
Conductive particles, a conductive material, and a connection structure were obtained in the same manner as in Example 1, except that the flux in the flux-containing particles and flux film was changed to benzylamine adipate.
　（実施例６）
　第１の導電部の形成の際に、ニッケルめっき液の代りに、硫酸銅２００ｇ／Ｌと、エチレンジアミン四酢酸１５０ｇ／Ｌと、グルコン酸ナトリウム１００ｇ／Ｌと、ホルムアルデヒド５０ｇ／Ｌとの混合液を、アンモニアにてｐＨ１０．５に調整した銅めっき液を用意した。懸濁液（Ａ）を６５℃にて撹拌しながら、銅めっき液を懸濁液（Ａ）に２５０ｍｌを１０ｍｌ／分で滴下し、無電解銅めっきを行った。その後、ｐＨが安定するまで撹拌し、水素の発泡が停止するのを確認した後、ろ過することにより、粒子を取り出し、水洗し、乾燥させて、基材粒子の表面上に第１の導電部（銅層、厚み０．２μｍ）を形成した。第１の導電部を銅層としたこと以外は、実施例１と同様にして、導電性粒子、導電材料及び接続構造体を得た。 (Example 6)
When forming the first conductive portion, instead of the nickel plating solution, a mixed solution of 200 g/L of copper sulfate, 150 g/L of ethylenediaminetetraacetic acid, 100 g/L of sodium gluconate, and 50 g/L of formaldehyde was used. A copper plating solution adjusted to pH 10.5 with ammonia was prepared. While the suspension (A) was stirred at 65° C., 250 ml of the copper plating solution was dropped into the suspension (A) at 10 ml/min to perform electroless copper plating. After that, the particles are taken out by filtration, washed with water, dried, and the first conductive portion is formed on the surface of the substrate particles. (copper layer, thickness 0.2 μm) was formed. A conductive particle, a conductive material, and a connection structure were obtained in the same manner as in Example 1, except that the first conductive portion was a copper layer.
　（実施例７）
　導電性粒子本体の作製において、芯物質を用いず、突起を形成しなかったこと、及び、導電部の形成の際に、錫層（０．３μｍ）のみを形成したこと以外は、実施例１と同様にして、導電性粒子、導電材料及び接続構造体を得た。 (Example 7)
Example 1 except that no core substance was used and no projections were formed in the preparation of the conductive particle body, and only a tin layer (0.3 μm) was formed in the formation of the conductive portion. Conductive particles, a conductive material and a connection structure were obtained in the same manner.
　（実施例８）
　導電性粒子本体の作製において、導電部として、ニッケル層（０．３μｍ）のみを形成したこと以外は、実施例１と同様にして、導電性粒子、導電材料及び接続構造体を得た。 (Example 8)
A conductive particle, a conductive material, and a connection structure were obtained in the same manner as in Example 1, except that only a nickel layer (0.3 μm) was formed as the conductive portion in the preparation of the conductive particle body.
　（実施例９）
　実施例１で得られた第１の導電部（ニッケル－ボロン層）を有する基材粒子を、蒸留水１００重量部に添加し、分散させることにより、懸濁液を得た。その後、第２の導電部の形成の際に、錫めっき液の代りに、シアン化金０．０３ｍｏｌ／Ｌと、還元剤としてヒドロキノン０．１ｍｏｌ／Ｌとを含む還元金めっき液を用意した。得られた懸濁液を７０℃にて撹拌しながら、還元金めっき液を懸濁液に徐々に滴下し、還元金めっきを行った。その後、懸濁液をろ過することにより、粒子を取り出し、水洗し、乾燥させて、第１の導電部（ニッケル－ボロン層、厚み０．２μｍ）及び第２の導電部（金層、厚み０．２５μｍ）を有する導電性粒子本体を得た。得られた導電性粒子本体を用いたこと以外は、実施例１と同様にして、導電性粒子、導電材料及び接続構造体を得た。 (Example 9)
The substrate particles having the first conductive portion (nickel-boron layer) obtained in Example 1 were added to 100 parts by weight of distilled water and dispersed to obtain a suspension. After that, a reducing gold plating solution containing 0.03 mol/L of gold cyanide and 0.1 mol/L of hydroquinone as a reducing agent was prepared instead of the tin plating solution when forming the second conductive portion. While stirring the resulting suspension at 70° C., the reduction gold plating solution was gradually dropped into the suspension to perform reduction gold plating. After that, by filtering the suspension, the particles are taken out, washed with water, and dried to form the first conductive portion (nickel-boron layer, thickness 0.2 μm) and the second conductive portion (gold layer, thickness 0.2 μm). .25 μm) was obtained. A conductive particle, a conductive material, and a connection structure were obtained in the same manner as in Example 1, except that the obtained conductive particle body was used.
　（比較例１）
　導電性粒子本体の表面上にフラックス含有粒子を配置しなかったこと以外は、実施例１と同様にして、導電性粒子、導電材料及び接続構造体を得た。 (Comparative example 1)
Conductive particles, a conductive material, and a connection structure were obtained in the same manner as in Example 1, except that the flux-containing particles were not arranged on the surface of the conductive particle body.
　（比較例２）
　導電性粒子本体の表面上にフラックス含有粒子を配置しなかったこと以外は、実施例８と同様にして、導電性粒子、導電材料及び接続構造体を得た。 (Comparative example 2)
Conductive particles, a conductive material, and a connection structure were obtained in the same manner as in Example 8, except that the flux-containing particles were not placed on the surface of the conductive particle body.
　（比較例３）
　導電性粒子本体の表面上にフラックス含有粒子を配置しなかったこと以外は、実施例９と同様にして、導電性粒子、導電材料及び接続構造体を得た。 (Comparative Example 3)
Conductive particles, a conductive material, and a connection structure were obtained in the same manner as in Example 9, except that the flux-containing particles were not placed on the surface of the conductive particle body.
　（比較例４）
　導電性粒子本体の表面上にフラックス膜を配置しなかったこと以外は、実施例１と同様にして、導電性粒子、導電材料及び接続構造体を得た。 (Comparative Example 4)
Conductive particles, a conductive material, and a connection structure were obtained in the same manner as in Example 1, except that no flux film was placed on the surface of the conductive particle body.
　（評価）
　（１）基材粒子、フラックス含有粒子、及び導電性粒子の粒子径、導電部及びフラックス膜の厚み
　得られた導電性粒子について、基材粒子、フラックス含有粒子、及び導電性粒子の粒子径、導電部及びフラックス膜の厚みを、上述した方法で測定した。なお、各粒子径は、２０個の測定結果を平均することにより算出した。 (evaluation)
(1) Particle diameters of base particles, flux-containing particles, and conductive particles, thickness of conductive portion and flux film The thickness of the conductive portion and the flux film were measured by the method described above. Each particle size was calculated by averaging 20 measurement results.
　また、導電性粒子の粒子径の、フラックス含有粒子の粒子径に対する比（導電性粒子の粒子径／フラックス含有粒子の粒子径）を算出した。 Also, the ratio of the particle size of the conductive particles to the particle size of the flux-containing particles (particle size of the conductive particles/particle size of the flux-containing particles) was calculated.
　（２）圧縮－変位曲線における破壊点の有無
　微小圧縮試験機（エリオニクス社製「ＥＮＴ－ＮＥＸＵＳ」）を用いて、円柱（直径５０μｍ、ダイヤモンド製）の平滑圧子端面で、２５℃、最大試験荷重３．３ｍＮを１０秒かけて負荷する条件下でフラックス含有粒子を圧縮した。このときの荷重値（Ｎ）及び圧縮変位（ｍｍ）を測定し、圧縮－変位曲線を作製し、破壊点の有無を確認した。 (2) Presence or absence of rupture point in compression-displacement curve Using a microcompression tester ("ENT-NEXUS" manufactured by Elionix), a cylinder (diameter 50 μm, made of diamond) was applied at a smooth indenter end face at 25 ° C., maximum test load. The flux-containing particles were compressed under the condition of loading 3.3 mN for 10 seconds. The load value (N) and compression displacement (mm) at this time were measured, a compression-displacement curve was prepared, and the presence or absence of breaking points was confirmed.
　（３）フラックス含有粒子の残存率
　得られた導電性粒子について、上述した方法で、フラックス含有粒子の残存率（％）を測定した。 (3) Remaining Percentage of Flux-Containing Particles The residual percentage (%) of flux-containing particles of the obtained conductive particles was measured by the method described above.
　（４）酸化被膜の除去性
　得られた導電材料について、導電性粒子を１重量％硫酸水溶液でＣｕ板上に散布した。その後、ホットプレートにて２５０℃で１分加熱し、加熱後十分に冷却し粒子を除去した。酸化被膜の除去性を、下記の基準（Ｃｕ板の色）で判定した。 (4) Removability of Oxide Film With respect to the obtained conductive material, conductive particles were dispersed on a Cu plate with a 1% by weight sulfuric acid aqueous solution. After that, it was heated on a hot plate at 250° C. for 1 minute, and after the heating, it was sufficiently cooled to remove the particles. The removability of the oxide film was judged according to the following criteria (color of Cu plate).
　［酸化被膜の除去性の判定基準］
　○○○：Ｃｕ板が橙色である
　○○：Ｃｕ板が赤橙色である
　○：Ｃｕ板が紫色である
　×：Ｃｕ板が銀・緑色である [Criteria for removability of oxide film]
○○○: The Cu plate is orange ○○: The Cu plate is reddish orange ○: The Cu plate is purple ×: The Cu plate is silver and green
　（５）導通信頼性（上下の電極間）
　得られた２０個の接続構造体の上下の電極間の接続抵抗をそれぞれ、４端子法により測定した。なお、電圧＝電流×抵抗の関係から、一定の電流を流した時の電圧を測定することにより接続抵抗を求めることができる。導通信頼性を下記の基準で判定した。 (5) Continuity reliability (between upper and lower electrodes)
The connection resistance between the upper and lower electrodes of the obtained 20 connection structures was measured by the 4-probe method. From the relationship of voltage=current×resistance, the connection resistance can be obtained by measuring the voltage when a constant current flows. Conductivity reliability was determined according to the following criteria.
　［導通信頼性の判定基準］
　○○○：接続抵抗が、０．３２Ω以下
　○○：接続抵抗が、０．３２Ωを超え０．３５Ω以下
　○：接続抵抗が、０．３５Ωを超え０．４１Ω以下
　×：接続抵抗が、０．４１Ωを超える [Continuity Reliability Judgment Criteria]
○○○: Connection resistance is 0.32 Ω or less ○○: Connection resistance is over 0.32 Ω and 0.35 Ω or less ○: Connection resistance is over 0.35 Ω and 0.41 Ω or less ×: Connection resistance is 0 over .41Ω
　結果を下記の表１～３に示す。 The results are shown in Tables 1 to 3 below.
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000001
Figure JPOXMLDOC01-appb-T000002
Figure JPOXMLDOC01-appb-T000002
Figure JPOXMLDOC01-appb-T000003
Figure JPOXMLDOC01-appb-T000003
　１，１Ａ，１Ｂ，１Ｃ…導電性粒子
　１１，１１Ａ，１１Ｂ，１１Ｃ…導電性粒子本体
　１１Ｃａ…突起
　１２，１２Ａ，１２Ｂ，１２Ｃ…フラックス含有粒子
　１３，１３Ａ，１３Ｂ，１３Ｃ…フラックス膜
　２１，２１Ａ，２１Ｂ，２１Ｃ…基材粒子
　２２，２２Ａ，２２Ｂ，２２Ｃ…導電部
　２２ＢＡ…第１の導電部
　２２ＢＢ…第２の導電部
　２３Ｃ…芯物質
　８１…接続構造体
　８２…第１の接続対象部材
　８２ａ…第１の電極
　８３…第２の接続対象部材
　８３ａ…第２の電極
　８４…接続部 1, 1A, 1B, 1C... Conductive particles 11, 11A, 11B, 11C... Conductive particle body 11Ca... Protrusions 12, 12A, 12B, 12C... Flux-containing particles 13, 13A, 13B, 13C... Flux films 21, 21A , 21B, 21C... Base material particles 22, 22A, 22B, 22C... Conductive part 22BA... First conductive part 22BB... Second conductive part 23C... Core substance 81... Connection structure 82... First connection target member 82a ... 1st electrode 83 ... 2nd connection object member 83a ... 2nd electrode 84 ... connection part

Claims (10)

  1. 　導電性粒子本体と、複数のフラックス含有粒子と、フラックス膜とを備え、
    　前記導電性粒子本体が、基材粒子と、前記基材粒子の外側に配置された導電部とを備え、
    　前記フラックス含有粒子が、前記導電性粒子本体の外側に配置されており、
    　前記フラックス膜が、前記導電性粒子本体の外側に配置されている、導電性粒子。     A conductive particle body, a plurality of flux-containing particles, and a flux film,
    The conductive particle body comprises a base particle and a conductive portion arranged outside the base particle,
    The flux-containing particles are arranged outside the conductive particle body,
    Conductive particles, wherein the flux film is disposed outside the conductive particle body.
  2. 　前記フラックス含有粒子が、粒子本体と、フラックスとを含み、
    　前記粒子本体が、樹脂粒子である、請求項１に記載の導電性粒子。     the flux-containing particles comprise a particle body and a flux,
    2. The conductive particles according to claim 1, wherein the particle bodies are resin particles.
  3. 　前記樹脂粒子の材料が、重合性単量体を含み、
    　前記重合性単量体の単独重合体のガラス転移温度が、８０℃以上である、請求項２に記載の導電性粒子。     the material of the resin particles contains a polymerizable monomer,
    3. The conductive particles according to claim 2, wherein the homopolymer of the polymerizable monomer has a glass transition temperature of 80[deg.] C. or higher.
  4. 　前記フラックス含有粒子が、前記フラックス含有粒子に最大試験荷重３．３ｍＮを１０秒かけて負荷したときの圧縮－変位曲線において、破壊点を有しない、請求項１～３のいずれか１項に記載の導電性粒子。 4. The flux-containing particles according to any one of claims 1 to 3, wherein the flux-containing particles do not have a breaking point in a compression-displacement curve when a maximum test load of 3.3 mN is applied to the flux-containing particles for 10 seconds. conductive particles.
  5. 　前記導電部が、錫を含む、請求項１～４のいずれか１項に記載の導電性粒子。 The conductive particles according to any one of claims 1 to 4, wherein the conductive portion contains tin.
  6. 　前記導電性粒子の粒子径の、前記フラックス含有粒子の粒子径に対する比が、３以上５００以下である、請求項１～５のいずれか１項に記載の導電性粒子。 The conductive particles according to any one of claims 1 to 5, wherein the ratio of the particle size of the conductive particles to the particle size of the flux-containing particles is 3 or more and 500 or less.
  7. 　前記導電性粒子の粒子径が、１μｍ以上５０μｍ以下である、請求項１～６のいずれか１項に記載の導電性粒子。 The conductive particles according to any one of claims 1 to 6, wherein the conductive particles have a particle diameter of 1 µm or more and 50 µm or less.
  8. 　エタノール１００重量部に、前記導電性粒子３重量部を添加した導電性粒子含有液を２０℃及び４０ｋＨｚの条件で５分間超音波処理したときに、下記式（１）により求められるフラックス含有粒子の残存率が９９％以下である、請求項１～７のいずれか１項に記載の導電性粒子。
    　フラックス含有粒子の残存率（％）＝（超音波処理後のフラックス含有粒子による被覆率／超音波処理前のフラックス含有粒子による被覆率）×１００・・・式（１）     When a conductive particle-containing liquid obtained by adding 3 parts by weight of the conductive particles to 100 parts by weight of ethanol is subjected to ultrasonic treatment for 5 minutes at 20° C. and 40 kHz, the number of flux-containing particles obtained by the following formula (1) is The conductive particles according to any one of claims 1 to 7, which have a residual rate of 99% or less.
    Remaining rate of flux-containing particles (%)=(coverage ratio of flux-containing particles after ultrasonic treatment/coverage ratio of flux-containing particles before ultrasonic treatment)×100 Equation (1)
  9. 　請求項１～８のいずれか１項に記載の導電性粒子と、バインダー樹脂とを含む、導電材料。 A conductive material comprising the conductive particles according to any one of claims 1 to 8 and a binder resin.
  10. 　第１の電極を表面に有する第１の接続対象部材と、
    　第２の電極を表面に有する第２の接続対象部材と、
    　前記第１の接続対象部材と、前記第２の接続対象部材を接続している接続部とを備え、
    　前記接続部の材料が、請求項１～８のいずれか１項に記載の導電性粒子を含み、
    　前記第１の電極と前記第２の電極とが、前記導電性粒子本体により電気的に接続されている、接続構造体。     a first connection target member having a first electrode on its surface;
    a second connection target member having a second electrode on its surface;
    comprising the first connection target member and a connection portion connecting the second connection target member,
    The material of the connection portion contains the conductive particles according to any one of claims 1 to 8,
    A connection structure in which the first electrode and the second electrode are electrically connected by the conductive particle body.
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