TWI381037B - An electrically conductive particles having an insulating particle, an anisotropic conductive material, and a connecting structure - Google Patents

Description

Conductive particles with an insulating particle, an anisotropic conductive material, and a connection structure

The present invention relates to a conductive particle coated with insulating particles and a method for producing the conductive particle with the insulating particle, which can be used for electrical connection between electrodes, and a conductive method using the insulating particle An anisotropic conductive material of a particle and a bonded structure.

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

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

In one example of the above-mentioned conductive particles, the following Patent Document 1 discloses conductive particles having insulating particles, which are provided with conductive particles and are fixed to the surface of the conductive particles and have a fixing property. Insulating particles. The insulating particles have hard particles and a polymer resin layer covering the surface of the hard particles. Here, in order to fix the insulating particles on the surface of the conductive particles, a physical/mechanical mixing method can be used as the immobilization method.

Patent Document 2 discloses an electrically conductive particle having insulating particles, which has conductive particles having a polar group on at least a part of the surface, at least a part of a surface covering the conductive particles, and includes insulation. Insulating material for particles. The insulating material specifically includes a polymer electrolyte that can be adsorbed to the polar group and inorganic oxide particles that can be adsorbed to the polymer electrolyte. The inorganic oxide particles are insulating particles.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2007-537570

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2008-120990

In the conductive particles having insulating particles attached as described in Patent Documents 1 and 2, at least a part of the conductive layer is exposed. Therefore, rust is easily generated on the surface of the conductive layer due to a corrosive gas in the atmosphere or a corrosive substance in the anisotropic conductive material. Therefore, there is a phenomenon that the high conductivity cannot be sufficiently maintained over a long period of time. In addition, when the conductive particles are used to form rust-attached conductive particles with insulating particles and the electrodes are connected to each other, the electrodes are not reliably electrically connected to each other, or the connection resistance between the electrodes is increased.

Further, in the conductive particles having the insulating particles described above, the insulating particles are easily detached from the surface of the conductive particles. For example, when the conductive particles having the insulating particles are dispersed in the binder resin, the insulating particles are likely to be detached from the surface of the conductive particles.

In particular, as described in Patent Document 1, when the insulating particles are fixed to the surface of the conductive particles and a physical/mechanical mixing method is used, the insulating particles are likely to be detached from the surface of the conductive particles.

Further, when a physical/mechanical hybrid method is used, there is a problem that the polymer resin layer of the insulating particles adheres to a portion other than the portion of the surface of the conductive particles to which the insulating particles are adhered. Conductivity is easily impaired after the electrodes are connected.

An object of the present invention is to provide a conductive particle-attached conductive material which is difficult to generate rust in a conductive layer and can maintain high electrical conductivity over a long period of time, and thus can be used for connection between electrodes. The method for producing the particles and the conductive particles with the insulating particles, and the anisotropic conductive material and the bonded structure using the conductive particles with the insulating particles.

A limited object of the present invention is to provide an insulating particle-attached conductive particle in which insulating particles are hardly detached from the surface of the conductive particle, and a method for producing the conductive particle with the insulating particle, and the method of using the same An anisotropic conductive material having a conductive particle of an insulating particle and a bonded structure.

According to a broader aspect of the present invention, there is provided a conductive particle having insulating particles, comprising: a conductive particle body having insulating particles; and having conductive particles having a conductive layer at least on a surface thereof, and An insulating particle attached to the surface of the conductive particle; a film covering the surface of the conductive particle body with the insulating particles; and the coating film is composed of a compound having an alkyl group having 6 to 22 carbon atoms. form.

In a specific aspect of the conductive particles with insulating particles of the present invention, the insulating particles comprise inorganic particles.

In another specific aspect of the conductive particles with insulating particles of the present invention, the compound having an alkyl group having 6 to 22 carbon atoms is selected from the group consisting of phosphates or salts thereof, phosphites or salts thereof, At least one selected from the group consisting of alkoxy decane, alkyl thiol and dialkyl disulfide.

In still another specific aspect of the conductive particles with insulating particles of the present invention, the insulating particles have an insulating particle body and at least a portion of a surface covering the surface of the insulating particle body and are composed of a polymer compound. The layer formed.

In another specific aspect of the conductive particles with insulating particles of the present invention, the polymer compound is not adhered to a portion other than the portion of the conductive particles to which the insulating particles are adhered.

In another specific aspect of the conductive particles with insulating particles of the present invention, the polymer compound has at least one reaction selected from the group consisting of a (meth) acrylonitrile group, a glycidyl group, and a vinyl group. Sex functional group.

In another specific aspect of the conductive particles with insulating particles of the present invention, the insulating particles are not attached to the surface of the conductive particles by a mixing method.

In another specific aspect of the conductive particles with insulating particles of the present invention, the conductive particles coated with insulating particles are treated with a 5% by weight aqueous solution of citric acid to remove the film. After the treatment liquid containing the peeled coating film, the treatment liquid is filtered, and the obtained filtration liquid contains 50 to 10000 ppm of a phosphorus element or a lanthanum element.

In another specific aspect of the conductive particles with insulating particles of the present invention, the conductive particles coated with insulating particles are treated with a 5% by weight aqueous solution of citric acid to remove the coating film. After the treatment liquid containing the peeled film is obtained, the treatment liquid is filtered to obtain a phosphorus content of 50 to 10,000 ppm.

Further, according to a broader aspect of the present invention, there is provided a conductive particle having insulating particles, comprising: a conductive particle body having insulating particles, and having conductive particles having a conductive layer at least on a surface thereof And an insulating particle attached to the surface of the conductive particle; a film attached to the surface of the conductive particle body with the insulating particles; and an insulating particle attached by a 5% by weight aqueous solution of citric acid After the conductive particles are treated to peel off the coating film to obtain a treatment liquid containing the peeled coating film, the filtration liquid obtained by filtering the treatment liquid contains 50 to 10,000 ppm of a phosphorus element or a lanthanum element. In this case, it is preferred that the coating film is peeled off by treating the conductive particles coated with the insulating particles with a 5% by weight aqueous citric acid solution to obtain a treatment liquid containing the peeled coating film. The filtrate obtained by filtering the treatment liquid contains 50 to 10,000 ppm of phosphorus.

The connection structure according to the present invention includes: a first connection target member, a second connection target member, and a connection portion that connects the first and second connection target members; and the connection portion is made of an insulating particle according to the present invention. The conductive particles are formed or formed of an anisotropic conductive material containing the conductive particles with insulating particles and a binder resin.

Further, according to a broader aspect of the present invention, there is provided a method for producing conductive particles having insulating particles, comprising: conductive particles having a conductive layer at least on a surface thereof, and adhesion to a surface of the conductive particles The surface of the main body of the conductive particles with insulating particles attached to the insulating particles is a method of coating the surface of the conductive particle body with the insulating particles described above by using a compound having an alkyl group having 6 to 22 carbon atoms. Form a film.

In a specific aspect of the method for producing conductive particles with insulating particles according to the present invention, the conductive particles having the insulating particles have a hydroxyl group in at least a part of the surface, and the insulating layer is insulated. The hydroxyl group on the surface of the conductive particle body of the particles is reacted with a compound having a hydroxyl group having an alkyl group having 6 to 22 carbon atoms, and is formed to cover the surface of the conductive particle body having the insulating particles. membrane.

The anisotropic conductive material of the present invention comprises conductive particles having an insulating particle formed according to the present invention, a binder resin, or a method comprising the production method of the conductive particles with insulating particles of the present invention. Conductive particles with insulating particles and binder resin. The anisotropic conductive material of the present invention is preferably an anisotropic conductive paste.

In the conductive particles with insulating particles of the present invention, the surface of the conductive particles having the insulating particles is coated with a film, and the film is composed of a compound having an alkyl group having 6 to 22 carbon atoms. Formed, so it is difficult to produce rust on the conductive layer.

In the method for producing conductive particles with insulating particles according to the present invention, a compound having an alkyl group having 6 to 22 carbon atoms is used on the surface of the conductive particles having the insulating particles to coat the above. Since the coating film is formed so as to attach the surface of the conductive particles to the insulating particles, conductive particles having insulating particles which are less likely to cause rust in the conductive layer can be obtained.

Therefore, the conductive particles with insulating particles of the present invention or the conductive particles with insulating particles obtained by the method for producing conductive particles with insulating particles of the present invention are used. When the connection is made between, the conduction reliability between the electrodes can be improved.

Further, the conductive particles with insulating particles of the present invention have a coating adhered to the surface of the conductive particle body having the insulating particles, and are further insulated by a 5% by weight aqueous solution of citric acid. After the conductive particles of the particles are treated, the coating film is peeled off to obtain a treatment liquid containing the peeled coating film, and the filtration liquid obtained by filtering the treatment liquid contains 50 to 10000 ppm of a phosphorus element or a lanthanum element. In the case, it is also difficult to generate rust on the conductive layer. Therefore, when the conductive particles having the insulating particles of the present invention are used to connect the electrodes, the conduction reliability between the electrodes can be improved.

The invention will be clarified by the following description of specific embodiments and examples of the invention.

(The conductive particle body with insulating particles)

In Fig. 1, the conductive particles with insulating particles according to the first embodiment of the present invention are shown in cross section.

The conductive particles 1 with insulating particles shown in FIG. 1 include a conductive particle body 2 with insulating particles, and a film 3 covering the surface of the conductive particle body 2 with insulating particles. The film 3 is attached to the surface of the conductive particle body 2 to which the insulating particles are attached. The film 3 covers the entire surface of the conductive particle body 2 to which the insulating particles are attached.

The conductive particle main body 2 with insulating particles includes conductive particles 11 and a plurality of insulating particles 15 attached to the surface of the conductive particles 11. The insulating particles 15 are formed of a material having an insulating property.

The film 3 covers the surface of the conductive particles 11 and the surface of the insulating particles 15. The portion of the film 3 covering the surface of the conductive particles 11 is connected to the portion of the film 3 covering the surface of the insulating particles 15.

The conductive particles 11 have substrate particles 12 and a conductive layer 13 provided on the surface of the substrate particles 12. The conductive layer 13 covers the surface of the substrate particles 12. The conductive particles 11 are coated particles in which the surface of the substrate particles 12 is coated with the conductive layer 13 . The conductive particles 11 have a conductive layer 13 on the surface.

In Fig. 2, conductive particles with insulating particles according to a second embodiment of the present invention are shown in cross section.

The conductive particles 21 with insulating particles shown in FIG. 2 include a conductive particle body 22 with insulating particles and a coating film 23 covering the surface of the conductive particle body 22 with insulating particles. The film 23 is attached to the surface of the conductive particle body 22 to which the insulating particles are attached.

The conductive particle main body 22 with insulating particles includes conductive particles 31 and a plurality of insulating particles 15 attached to the surface of the conductive particles 31.

The film 23 covers the surface of the conductive particles 31 and the surface of the insulating particles 15. The portion of the film 23 covering the surface of the conductive particles 31 is connected to the portion of the film 23 covering the surface of the insulating particles 15.

The conductive particles 31 have a substrate particle 12 and a conductive layer 32 provided on the surface of the substrate particle 12. The conductive particles 31 have a plurality of core materials 33 on the surface of the substrate particles 12. The conductive layer 32 covers the substrate particles 12 and the core material 33. Since the conductive layer 32 covers the core material 33, the conductive particles 31 have a plurality of protrusions 34 on the surface. The surface of the conductive layer 32 is embossed by the core material 33, and a plurality of protrusions 34 are formed.

In Fig. 3, conductive particles with insulating particles according to a third embodiment of the present invention are shown in cross section.

The conductive particles 41 with insulating particles shown in FIG. 3 include a conductive particle body 42 with insulating particles and a film 3 covering the surface of the conductive particle body 42 with insulating particles.

The conductive particle main body 42 with insulating particles includes conductive particles 11 and a plurality of insulating particles 45 attached to the surface of the conductive particles 11. In other words, the conductive particles 41 with the insulating particles are formed in the same manner as the conductive particles 1 with the insulating particles, and the conductive particles body 42 with the insulating particles and the insulating layer are provided. The conductive particle body 2 of the particles is configured in the same manner.

The insulating particles 45 have an insulating particle body 45a and a layer 45b formed of a polymer compound covering the surface of the insulating particle body 45a. Due to the presence of the layer 45b, the adhesion of the insulating particles 45 to the conductive particles 11 can be appropriately improved.

The layer 45b covers the entire surface of the insulating particle body 45a. Therefore, the layer 45b is disposed between the conductive particles 11 and the insulating particle body 45a. The layer 45b may be present so as to cover at least a part of the surface of the insulating particle body, or may not cover the entire surface of the insulating particle body. Preferably, the layer 45b is disposed between the conductive particles and the insulating particle body.

In Fig. 4, conductive particles with insulating particles according to a fourth embodiment of the present invention are shown in cross section.

The conductive particles 61 with insulating particles shown in FIG. 4 include an insulating particle body 62 and a coating film 23 covering the surface of the conductive particle body 62 with insulating particles. The film 23 is attached to the surface of the conductive particle body 62 to which the insulating particles are attached.

The conductive particle body 62 with insulating particles includes conductive particles 71 and a plurality of insulating particles 15 attached to the surface of the conductive particles 71.

The conductive particles 71 have substrate particles 12 and a conductive layer 76 provided on the surface of the substrate particles 12. The conductive layer 76 has a first conductive layer 76a provided on the surface of the substrate particle 12, and a second conductive layer 76b provided on the surface of the first conductive layer 76a. The conductive particles 71 have a plurality of core materials 33 on the surface of the first conductive layer 76a. The second conductive layer 76b covers the first conductive layer 76a and the core material 33. The substrate particles 12 and the core material 33 are arranged at intervals. The first conductive layer 76a is present between the substrate particles 12 and the core material 33. Since the second conductive layer 76b covers the core material 33, the conductive particles 71 have a plurality of protrusions 77 on the surface. The surface of the conductive layer 76 and the second conductive layer 76b is embossed by the core material 33, and a plurality of protrusions 77 are formed.

Preferably, the surface of the conductive particle bodies 2, 22, 42, 62 to which the insulating particles are attached is covered with a film 3, 23 made of an alkyl group having a carbon number of 6-22. Formed by the compound. Thereby, it becomes difficult to generate rust on the conductive layers 13, 32, and 76 among the conductive particles 1, 21, 41, and 61 to which the insulating particles are attached. The coatings 3 and 23 impart an anti-rust effect. Therefore, the conductivity of the conductive particles in the conductive particles with the insulating particles is increased, and high conductivity can be maintained over a long period of time. Therefore, when the electrodes are connected using the conductive particles 1 , 21 , 41 , and 61 with the insulating particles, the conduction reliability can be improved.

Further, it is preferable that the conductive particles 1, 21, 41, and 61 with insulating particles are treated with a 5% by weight aqueous citric acid solution to peel off the coatings 3 and 23 to obtain a peeled coating. After the treatment liquid of the membranes 3 and 23, the treatment liquid is filtered, and the obtained filtrate contains 50 to 10,000 ppm of a phosphorus element or a lanthanum element. Thereby, it becomes difficult to generate rust on the conductive layers 13, 32, and 76 of the conductive particles 1, 21, 41, and 61 to which the insulating particles are attached. Therefore, the conductivity of the conductive particles in the conductive particles with the insulating particles is increased, and high conductivity can be maintained over a long period of time. Therefore, when the electrodes are connected using the conductive particles 1 , 21 , 41 , and 61 with the insulating particles, the conduction reliability can be improved.

Further, from the viewpoint that it is further difficult to generate rust in the conductive layer, it is preferred to treat the conductive particles 1, 21, 41, and 61 with insulating particles in a 5% by weight aqueous solution of citric acid. After the coating films 3 and 23 are peeled off, and the treatment liquid containing the peeled coatings 3 and 23 is obtained, the filtration liquid obtained by filtering the treatment liquid contains 50 to 10,000 ppm of phosphorus element. From the viewpoint of further making it difficult to generate rust in the conductive layer, it is preferred to coat the conductive particles 1, 21, 41, and 61 with insulating particles in a 5% by weight aqueous solution of citric acid. 3 and 23 are peeled off, and the treatment liquid containing the peeled coatings 3 and 23 is obtained, and the obtained liquid is filtered, and the obtained filtrate contains 50 to 10000 ppm of cerium element. The content of the lanthanum element or the phosphorus element in the above filtrate is more preferably 100 ppm or more, more preferably 5,000 ppm or less, still more preferably 1,000 ppm or less.

The content of the above phosphorus element and cerium element can be measured using an ICP luminescence analyzer. As a commercial item of the ICP luminescence analyzer, "ULTIMA2" manufactured by Horiba, Ltd., and the like can be cited.

In the case of the conductive particles 1, 21, 41, and 61 having the insulating particles coated with the coatings 3 and 23, the content of the phosphorus element and the cerium element is usually determined by the coatings 3 and 23. That is, the content of the phosphorus element and the above-mentioned lanthanum element indicates the ratio of the phosphorus element and the lanthanum element in the coating films 3 and 23.

It is preferable that the coating films 3 and 23 are attached to the surfaces of the conductive particle bodies 2, 22, 42, 62 to which the insulating particles are attached. In the conductive particles 1, 21, 41, and 61 with insulating particles, it is preferable that the coatings 3 and 23 cover the entire surface of the conductive particles 2, 22, 42, and 62 to which the insulating particles are attached.

Further, it is not necessary for the coating films 3 and 23 to cover the entire surface of the conductive particle bodies 2, 22, 42, and 62 to which the insulating particles are attached. Since the coatings 3, 23 cover at least a part of the surface of the conductive layers 13, 32, 76, the rust of the conductive layers 23, 32, 76 can be suppressed in the portions where the coatings 3, 23 are formed.

Further, in the conductive particles 1, 21, 41, and 61 in which the insulating particles are provided, the insulating particles 15 and 45 become difficult to form from the surfaces of the conductive particles 11, 31, and 71 due to the presence of the coating films 3 and 23. Get rid of. For example, when the conductive particles 1, 21, 41, and 61 with the insulating particles are added to the binder resin and kneaded, the insulating particles 15 and 45 are less likely to be detached from the surfaces of the conductive particles 11, 31, and 71. Further, when a plurality of conductive particles 1, 21, 41, and 61 having insulating particles are in contact with each other, the insulating particles 15 and 45 are less likely to be detached from the surfaces of the conductive particles 11, 31, and 71 due to the impact at the time of contact. Therefore, when the conductive particles 1, 21, 41, and 61 with the insulating particles are used for the connection between the electrodes, the insulating particles 15 and 45 are present between the adjacent conductive particles 11, 31, and 71. It is difficult to electrically connect between adjacent electrodes that cannot be connected.

Hereinafter, the details of the coatings 3 and 23 and the details of the conductive particles main bodies 2, 22, 42, and 62 to which the insulating particles are attached will be described.

[filming]

In order to make it difficult to generate rust in the conductive layer, it is preferred that the film be formed of a compound having an alkyl group having 6 to 22 carbon atoms (hereinafter also referred to as Compound A). If the carbon number of the above alkyl group is less than 6, it becomes easy to generate rust on the surface of the conductive layer. When the carbon number of the alkyl group exceeds 22, the conductivity of the conductive particles with the insulating particles is lowered. From the viewpoint of further improving the conductivity of the conductive particles with insulating particles, it is preferred that the number of carbon atoms of the alkyl group in the compound A is 16 or less. The above alkyl group may have a linear structure or a branched structure. It is preferred that the above alkyl group has a linear structure.

The above compound A is not particularly limited as long as it has an alkyl group having 6 to 22 carbon atoms. The above compound A is preferably selected from the group consisting of a phosphate having a carbon number of 6 to 22 or a salt thereof, a phosphite having an alkyl group having 6 to 22 carbon atoms or a salt thereof, and having a carbon number of 6~ At least a group of 22 alkyl alkoxy decane, an alkyl thiol having an alkyl group having 6 to 22 carbon atoms, and a dialkyl disulfide having an alkyl group having 6 to 22 carbon atoms 1 species. That is, the above compound A having an alkyl group having 6 to 22 carbon atoms is preferably selected from the group consisting of a phosphate ester or a salt thereof, a phosphite or a salt thereof, an alkoxydecane, an alkylthiol and a dialkyl group. At least one of the group consisting of thioethers. By using these preferred compounds A, it is further difficult to produce rust on the conductive layer. The compound A is preferably at least one selected from the group consisting of the above-mentioned phosphate or a salt thereof, a phosphite or a salt thereof, and an alkoxydecane, and more preferably At least one of the above phosphate ester or a salt thereof and a phosphite ester or a salt thereof. The above-mentioned compound A may be used alone or in combination of two or more.

It is preferred that the above compound A has a reactive functional group reactive with conductive particles. It is preferred that the above compound A has a reactive functional group reactive with insulating particles. Preferably, the film is chemically bonded to the conductive particles having the insulating particles attached thereto. Preferably, the film is chemically bonded to the conductive particles. Preferably, the film is chemically bonded to the insulating particles. More preferably, the film is chemically bonded to the conductive particles and the insulating particles. Due to the presence of the above reactive functional groups and due to the above chemical bonding, it becomes difficult to cause peeling of the film. As a result, it is further difficult to generate rust on the conductive layer, and unexpectedly, the insulating particles are more difficult to be detached from the surface of the conductive particles.

Examples of the phosphate or a salt thereof having an alkyl group having 6 to 22 carbon atoms include hexyl phosphate, heptyl phosphate, monooctyl phosphate, monodecyl phosphate, monodecyl phosphate, and Monoundecyl phosphate, monododecyl phosphate, monotridecyl phosphate, monotetradecyl phosphate, monopentadecyl phosphate, monohexyl phosphate monophosphate, phosphate Heptyl monoester monosodium salt, monooctyl phosphate monosodium salt, monodecyl phosphate monosodium salt, monodecyl phosphate monosodium salt, monoundecyl phosphate monosodium salt, monododecyl phosphate A monosodium salt of a monoester, a monosodium salt of monotridecyl phosphate, a monosodium salt of monotetradecyl phosphate, and a monosodium salt of monopentadecyl phosphate. The potassium salt of the above phosphate can also be used.

Examples of the phosphite having a C 6-22 alkyl group or a salt thereof include hexyl phosphite, heptyl phosphite, monooctyl phosphite, monodecyl phosphite, and phosphorous acid. Monodecyl ester, monoundecyl phosphite, monododecyl phosphite, monotridecyl phosphite, monotetradecyl phosphite, monopentadecyl phosphite, Monohexyl phosphite monosodium salt, monoheptyl phosphite monosodium salt, monooctyl phosphite monosodium salt, monodecyl phosphite monosodium salt, monodecyl phosphite monosodium salt, sub Monodecyl phosphate monosodium salt, monododecyl phosphite monosodium salt, monotridecyl phosphite monosodium salt, monotetradecyl phosphite monosodium salt and phosphite single Pentadecyl ester monosodium salt and the like. The potassium salt of the above phosphite may also be used.

Examples of the alkoxydecane having an alkyl group having 6 to 22 carbon atoms include hexyltrimethoxydecane, hexyltriethoxydecane, heptyltrimethoxynonane, heptyltriethoxydecane, and octyl. Trimethoxy decane, octyl triethoxy decane, decyl trimethoxy decane, decyl triethoxy decane, decyl trimethoxy decane, decyl triethoxy decane, undecyl trimethoxy Basear, undecyltriethoxydecane, dodecyltrimethoxydecane, dodecyltriethoxydecane,tridecyltrimethoxydecane,tridecyltriethoxydecane , tetradecyl trimethoxy decane, tetradecyl triethoxy decane, pentadecyl trimethoxy decane, pentadecyl triethoxy decane, and the like.

Examples of the alkylthiol having an alkyl group having 6 to 22 carbon atoms include hexyl mercaptan, heptyl mercaptan, octyl mercaptan, mercapto mercaptan, mercapto mercaptan, and undecyl sulfur. Alcohol, dodecyl mercaptan, tridecyl mercaptan, tetradecyl mercaptan, pentadecyl mercaptan and cetyl mercaptan. The above alkylthiol preferably has a mercapto group at the end of the alkyl chain.

Examples of the dialkyl disulfide having an alkyl group having 6 to 22 carbon atoms include dihexyl disulfide, diheptyl disulfide, dioctyl disulfide, and dimercapto disulfide. Dimercapto disulfide, di-undecyl disulfide, di-dodecyl disulfide, di-tridecyl disulfide, di-tetradecyl disulfide, di-ten Pentaalkyl disulfide and di-hexadecyl disulfide.

[Electromagnetic particle body with insulating particles]

The conductive particles may have a conductive layer at least on the surface. The conductive particles may be conductive particles having a substrate particle and a conductive layer provided on the surface of the substrate particle, or may be metal particles having a conductive layer as a whole. Among them, from the viewpoint of reducing the cost, improving the flexibility of the conductive particles, and improving the conduction reliability between the electrodes, it is preferable to have the substrate particles and the conductive particles provided on the surface of the substrate particles. .

Examples of the substrate particles include resin particles, inorganic particles, organic-inorganic hybrid particles, and metal particles.

The substrate particles are preferably resin particles formed of a resin. When the electrodes are connected by using the conductive particles with the insulating particles, the conductive particles with the insulating particles are placed between the electrodes, and then the conductive particles with the insulating particles are bonded by pressure bonding. compression. When the base material particles are resin particles, the conductive particles are easily deformed at the time of the pressure bonding, and the contact area between the conductive particles and the electrode can be increased. Therefore, the conduction reliability between the electrodes can be improved.

Examples of the resin for forming the above resin particles include a polyolefin resin, an acrylic resin, a phenol resin, a melamine resin, a benzoguanamine resin, a urea resin, an epoxy resin, an unsaturated polyester resin, a saturated polyester resin, and a poly Ethylene terephthalate, polyfluorene, polyphenylene ether, polyacetal, polyimide, polyamidoximine, polyetheretherketone, and polyether oxime. In order to easily control the hardness of the substrate particles to a suitable range, the resin for forming the resin particles is preferably obtained by polymerizing one or two or more kinds of polymerizable monomers having an ethylenically unsaturated group. The polymer.

Examples of the inorganic material for forming the inorganic particles include cerium oxide, carbon black, and the like. Examples of the organic-inorganic hybrid particles include organic-inorganic hybrid particles formed by crosslinking an alkoxysilane alkyl polymer and an acrylic resin.

In the case where the substrate particles are metal particles, examples of the metal for forming the metal particles include silver, copper, nickel, rhodium, gold, titanium, and the like.

The metal for forming the above conductive layer is not particularly limited. Further, in the case where the entire conductive particles are metal particles of the conductive layer, the metal for forming the metal particles is not particularly limited. Examples of the metal include gold, silver, palladium, copper, platinum, palladium, zinc, iron, tin, lead, aluminum, cobalt, indium, nickel, chromium, titanium, ruthenium, osmium, iridium, osmium, cadmium, and antimony. And such alloys and the like. Further, examples of the metal include tin-doped indium oxide (ITO), solder, and the like. Among them, in order to further reduce the connection resistance between the electrodes, an alloy containing tin, nickel, palladium, copper or gold is preferred, and nickel or palladium is preferred.

When rust is more likely to occur in the metal constituting the above-mentioned conductive layer, the coating effect of the above-mentioned film is more remarkable. In the conductive layer formed of nickel, copper or tin, rust is more likely to occur on the surface of the conductive layer. By coating the surface of such a conductive layer with a film, rust can be effectively suppressed from occurring on the surface of the conductive layer. In order to effectively obtain the coating effect of the above film, the above conductive layer may also contain nickel, copper or tin.

Further, on the surface of the conductive layer, hydroxide is often present due to oxidation. In general, on the surface of the conductive layer formed of nickel, hydroxide is present due to oxidation. Such a conductive layer having a hydroxide is chemically bonded to the coating.

The above conductive layer is formed of one layer. The conductive layer may also be formed of a plurality of layers. That is, the conductive layer may have a laminated structure of two or more layers. In the case where the conductive layer is formed of a plurality of layers, the outermost layer is preferably a gold layer, a nickel layer, a palladium layer, a copper layer or an alloy layer containing tin and silver, more preferably a gold layer. In the case where the outermost layer is such a preferred conductive layer, the connection resistance between the electrodes can be further reduced. Further, when the outermost layer is a gold layer, the corrosion resistance can be further improved.

The method of forming the conductive layer on the surface of the substrate particles is not particularly limited. Examples of the method for forming the conductive layer include a method of electroless plating, a method using electroplating, a method using physical vapor deposition, and a method of applying a metal powder or a solder paste containing a metal powder and a binder to a substrate particle. Surface method, etc. Among them, in order to form the conductive layer simply, it is preferable to use an electroless plating method. Examples of the method using physical vapor deposition include vacuum vapor deposition, ion plating, and ion sputtering.

The average particle diameter of the above conductive particles is preferably in the range of 0.5 to 100 μm. The average particle diameter of the conductive particles is more preferably 1 μm or more, and still more preferably 20 μm or less. When the average particle diameter of the conductive particles is not less than the above lower limit and not more than the above upper limit, when the electrodes are connected by using the conductive particles with insulating particles, the contact between the conductive particles and the electrodes can be sufficiently increased. The area becomes too small to form agglomerated conductive particles when the conductive layer is formed. Moreover, the interval between the electrodes connected via the conductive particles is not excessively large, and the conductive layer is less likely to be peeled off from the surface of the substrate particles.

The "average particle diameter" of the above conductive particles means an arithmetic mean particle diameter. The average particle diameter of the conductive particles was determined by observing 50 arbitrary conductive particles by an electron microscope or an optical microscope, and calculating an average value.

The thickness of the above conductive layer is preferably in the range of 0.005 to 1 μm. The thickness of the conductive layer is more preferably 0.01 μm or more, and more preferably 0.3 μm or less. When the thickness of the conductive layer is not less than the above lower limit and not more than the above upper limit, sufficient conductivity can be obtained, and the conductive particles are not sufficiently hardened to sufficiently deform the conductive particles at the time of connection between the electrodes.

When the conductive layer is formed of a plurality of layers, the thickness of the outermost conductive layer, particularly when the outermost layer is a gold layer, is preferably in the range of 0.001 to 0.5 μm. A more preferred lower limit of the thickness of the outermost conductive layer is 0.01 μm, and a more preferred upper limit is 0.1 μm. When the thickness of the outermost conductive layer is not less than the above lower limit and not more than the above upper limit, the coating of the outermost conductive layer can be made uniform, the corrosion resistance can be sufficiently improved, and the connection resistance between the electrodes can be sufficiently reduced. Further, the thinner the thickness of the gold layer in the case where the outermost layer is a gold layer, the lower the cost.

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

The conductive particles preferably have protrusions on the surface of the conductive layer, and it is preferable that the plurality of protrusions are plural. An oxide film is often formed on the surface of the electrode to which the conductive particles having the insulating particles are attached. In the case where the conductive particles are provided on the surface of the conductive layer with the conductive particles coated with the insulating particles, the conductive particles are disposed between the electrodes, and the oxide film can be effectively removed by the protrusions. Therefore, the electrode can be further reliably contacted with the conductive layer, and the connection resistance between the electrodes can be reduced. Further, at the time of connection between the electrodes, the insulating particles between the conductive particles and the electrodes can be effectively removed by the protrusions of the conductive particles. Therefore, the conduction reliability between the electrodes can be improved.

The method of forming a protrusion on the surface of the conductive particle includes a method of forming a conductive layer by electroless plating after attaching a core substance to a surface of the substrate particle, and a surface of the substrate particle by electroless plating. After the conductive layer is formed, a core material is attached thereto, and a conductive layer is formed by electroless plating.

As a method of attaching a core material to the surface of the base material particle, for example, a conductive material which is a core material is added to the dispersion liquid of the base material particles, and the core material is deposited and adhered by, for example, van der Waals force. a method of coating the surface of the substrate particles; and adding a conductive material to be a core material to the container in which the substrate particles are placed, and attaching the core material to the surface of the substrate particles by mechanical action such as rotation of the container Method etc. Among them, in order to easily control the amount of the core material to be attached, a method of adhering the core material to the surface of the substrate particles in the dispersion liquid is preferred.

The conductive particles may have a first conductive layer on the surface of the substrate particles and a second conductive layer on the first conductive layer. In this case, the core substance may be attached to the surface of the first conductive layer. The core material is preferably coated with a second conductive layer. The thickness of the first conductive layer is preferably in the range of 0.05 to 0.5 μm. The conductive particles are preferably obtained by forming a first conductive layer on the surface of the substrate particles, and secondly attaching the core material to the surface of the first conductive layer, and then forming the first conductive layer and the core. A second conductive layer is formed on the surface of the substance.

Examples of the conductive material constituting the core material include a metal, a metal oxide, a conductive non-metal such as graphite, and a conductive polymer. Examples of the conductive polymer include polyacetylene and the like. Among them, in order to improve conductivity, a metal is preferred.

Examples of the metal include metals such as gold, silver, copper, platinum, zinc, iron, lead, tin, aluminum, cobalt, indium, nickel, chromium, titanium, ruthenium, osmium, iridium, and cadmium, and tin-lead alloys. An alloy composed of two or more kinds of metals, such as a tin-copper alloy, a tin-silver alloy, and a tin-lead-silver alloy. Preferred among these are nickel, copper, silver or gold. The metal constituting the core material may be the same as or different from the metal constituting the above-mentioned conductive layer.

The shape of the above core material is not particularly limited. The shape of the core material is preferably a block shape. Examples of the core material include a particulate block, agglomerates in which a plurality of fine particles are aggregated, and an amorphous block.

The insulating particles are insulating particles. The insulating particles are smaller than the conductive particles. When the electrodes are connected by using the conductive particles with the insulating particles, the short-circuit between the adjacent electrodes can be prevented by the insulating particles. Specifically, when a plurality of conductive particles having insulating particles are in contact with each other, insulating particles are present between the plurality of conductive particles having insulating particles with insulating particles, so that electrodes that are not up and down can be prevented. In between, it is a short circuit between adjacent electrodes in the lateral direction. Further, when the electrodes are connected to each other, the conductive particles having the insulating particles attached thereto are pressed by the two electrodes, whereby the insulating particles between the conductive layer and the electrodes can be easily removed. When the protrusions are provided on the surface of the conductive particles, the insulating particles between the conductive layer and the electrodes can be more easily removed.

Examples of the material constituting the insulating particles include an insulating resin and an insulating inorganic material. The above-mentioned resin which is exemplified as a resin for forming resin particles which can be used as the substrate particles is exemplified as the insulating resin. The above-mentioned inorganic substance exemplified as an inorganic substance for forming inorganic particles which can be used as the substrate particles is exemplified as the insulating inorganic material.

Specific examples of the insulating resin as the material of the insulating particles include a polyolefin, a (meth) acrylate polymer, a (meth) acrylate copolymer, a block polymer, a thermoplastic resin, and a thermoplastic resin. A crosslinked product, a thermosetting resin, a water-soluble resin, or the like.

Examples of the polyolefins include polyethylene, an ethylene-vinyl acetate copolymer, and an ethylene-acrylate copolymer. Examples of the (meth) acrylate polymer include poly(methyl) acrylate, poly(ethyl) acrylate, and poly(meth) acrylate. Examples of the block polymer include polystyrene, a styrene-acrylate copolymer, an SB-type styrene-butadiene block copolymer, and an SBS-type styrene-butadiene block copolymer, and Such as hydrides and the like. Examples of the thermoplastic resin include a vinyl polymer and an ethylene copolymer. Examples of the thermosetting resin include an epoxy resin, a phenol resin, and a melamine resin. Examples of the water-soluble resin include polyvinyl alcohol, polyacrylic acid, polypropylene decylamine, polyvinylpyrrolidone, polyethylene oxide, and methyl cellulose. Among them, a water-soluble resin is preferred, and polyvinyl alcohol is more preferred.

From the viewpoint of further improving the detachability of the insulating particles during thermocompression bonding, it is preferred that the insulating particles contain inorganic particles, preferably cerium oxide particles. In the case where the insulating particles do not have a layer formed of the above polymer compound on the surface, it is preferred that the insulating particles are inorganic particles, and preferably cerium oxide particles. In the case where the insulating particles of the layer formed of the above polymer compound are coated on the surface of the insulating particle body, it is preferred that the insulating particles are inorganic particles, and preferably cerium oxide particles. Examples of the inorganic particles include white sand particles, hydroxyphosphorus lime particles, magnesium oxide particles, zirconium oxide particles, and cerium oxide particles. From the viewpoint of further improving the detachment property of the insulating particles during thermocompression bonding, it is preferred that the insulating particles contain inorganic particles, and it is preferable that the inorganic particles are cerium oxide particles. Examples of the cerium oxide particles include pulverized cerium oxide and spherical cerium oxide, and spherical cerium oxide is preferably used. Further, the cerium oxide particles preferably have a functional group capable of chemically bonding, for example, a carboxyl group or a hydroxyl group on the surface, and more preferably have a hydroxyl group. The inorganic particles are relatively hard, especially the cerium oxide particles are relatively hard. In the case of using a conductive particle body having such insulating particles as the insulating particles, when the conductive particle body with the insulating particles and the binder resin are kneaded, the hard insulating particles are easy. Detach from the surface of the conductive particles. However, when the conductive particles with insulating particles of the present invention are used, even if hard insulating particles are used, the hard insulating particles can be prevented from being detached from the film during the kneading. The layer formed by the above polymer compound functions, for example, as a soft layer.

The polymer compound in the layer formed of the polymer compound or the compound which becomes the polymer compound by polymerization or the like is preferably a compound having a polymerizable reactive functional group. The polymerizable reactive functional group is preferably an unsaturated double bond. For example, a compound having an unsaturated double bond (a compound which is a polymer compound) may be polymerized on the surface of the insulating particle body, and a reactive functional group of the polymer compound and the surface of the insulating particle body may be used. reaction. Examples of the polymer compound or a compound which is the polymer compound include a compound having a (meth)acryl fluorenyl group, a compound having an epoxy group, and a compound having a vinyl group. When the conductive particles having the insulating particles are dispersed, the polymer compound or the compound which is the polymer compound is preferably selected from the viewpoint of suppressing the separation of the insulating particles from the surface of the conductive particles. At least one reactive functional group of a group consisting of a free (meth) acrylonitrile group, a glycidyl group, and a vinyl group. In particular, it is preferable that the polymer compound or the compound which is the polymer compound has a (meth) acrylonitrile group from the viewpoint of further suppressing the detachment of the insulating particles.

Specific examples of the compound having a (meth)acryl fluorenyl group include methacrylic acid, hydroxyethyl acrylate, and ethylene glycol dimethacrylate.

Specific examples of the epoxy compound include a bisphenol A type epoxy resin and resorcinol glycidyl ether.

Specific examples of the compound having a vinyl group include styrene and vinyl acetate.

The weight average molecular weight of the above polymer compound is preferably 1,000 or more. The upper limit of the weight average molecular weight of the polymer compound is not particularly limited, and it is preferred that the polymer compound has a weight average molecular weight of 20,000 or less. The weight average molecular weight represents a value in terms of polystyrene measured by gel permeation chromatography (GPC).

A method of forming a layer formed of the above polymer compound on the surface of the insulating particles is not particularly limited. It is preferable to form a layer formed of a polymer compound by using a polymer compound or a compound which is a polymer compound so as to cover at least a part of the surface of the surface of the insulating particle body, thereby obtaining insulating particles. An example of a method for forming a layer formed of the polymer compound is an insulating particle body having a surface of a compound having a reactive double bond and a hydroxyl group and an insulating particle having a reactive functional group such as a vinyl group. A method of performing polymerization on the surface or the like. However, methods other than the formation method can also be used.

Preferably, the insulating particle body is chemically bonded to the layer. The chemical bond includes a covalent bond, a hydrogen bond, an ionic bond, a coordinate bond, and the like. Among them, a covalent bond is preferred, and a chemical bond of a reactive functional group is preferably used.

Examples of the reactive functional group forming the above chemical bond include a vinyl group, a (meth)acryl fluorenyl group, a decyl group, a decyl group, a carboxyl group, an amine group, an ammonium group, a nitro group, a hydroxyl group, a carbonyl group, a decyl group, and a sulfonic acid group. A group, a thiol group, a boronic acid group, an oxazoline group, a pyrrolidinone group, a phosphate group, a nitrile group, and the like. Among them, a vinyl group or a (meth) acrylonitrile group is preferred.

The insulating particle body is preferably used as an insulating particle body having a reactive functional group on its surface, from the viewpoint of further suppressing the detachment of the insulating particles and further improving the insulation reliability of the bonded structure. From the viewpoint of further suppressing the detachment of the insulating particles and further improving the insulation reliability of the bonded structure, it is preferred that the insulating particle body is surface-treated using a compound having a reactive functional group. Insulating particle body. From the viewpoint of further suppressing the detachment of the insulating particles and further improving the insulation reliability of the bonded structure, it is preferable to use the insulating particle body and the polymer compound having a reactive functional group on the surface or to be high. a compound of a molecular compound, wherein a layer formed by the polymer compound is chemically bonded to a reactive functional group on a surface of the insulating particle body, thereby obtaining the insulating material in which the insulating particle body and the layer are chemically bonded Sex particles.

Examples of the reactive functional group which the insulating particle body has on the surface include a (meth)acryl fluorenyl group, a glycidyl group, a hydroxyl group, a vinyl group, and an amine group. The reactive functional group on the surface of the insulating particles is preferably at least one reactive group selected from the group consisting of a (meth) acryl group, a glycidyl group, a hydroxyl group, a vinyl group, and an amine group. Functional group.

Examples of the compound (surface-treating substance) for introducing the reactive functional group on the surface of the insulating particle main body include a compound having a (meth)acryl fluorenyl group, a compound having an epoxy group, and a compound having a vinyl group. Wait.

Examples of the compound (surface-treating material) for introducing a vinyl group as the reactive functional group on the surface of the insulating particle body include a vinyl decane compound, a vinyl compound having a vinyl group, and a vinyl group. Phosphoric acid compounds and the like. The above surface treatment substance is preferably a decane compound having a vinyl group. Examples of the vinyl group-containing decane compound include vinyl trimethoxy decane, vinyl triethoxy decane, vinyl triethoxy decane, and vinyl triisopropoxy decane.

The compound (surface-treating substance) for introducing a (meth)acryl fluorenyl group as the reactive functional group on the surface of the insulating particle body, a decane compound having a (meth) acrylonitrile group, and A (meth)acryloyl group-based titanium compound, a (meth)acryloyl group-containing phosphate compound, and the like. The surface treatment material is preferably a decane compound having a (meth) acrylonitrile group. Examples of the decane compound having a (meth)acryl fluorenyl group include (meth)acryloxypropyltriethoxydecane, (meth)acryloxypropyltrimethoxydecane, and (methyl). Propylene methoxypropyl dimethoxy decane, and the like.

It is preferable that the insulating particles are formed not by friction generated by mixing the main body of the insulating particles with a polymer compound or a compound which is a polymer compound. Further, it is preferable that the surface of the insulating particle body is not covered by the layer by a mixing method. When the insulating particles are formed by friction or mixing by mixing, the layer is easily detached from the surface of the insulating particle body. Moreover, it becomes easy to attach a fragment of the layer formed at the time of kneading on the surface of the insulating particle. Therefore, there is a tendency that the detached layer or the fragment of the layer is adhered to the surface of the conductive layer on which the conductive particles of the insulating particles are attached, and the conduction reliability of the bonded structure is likely to be lowered. Therefore, from the viewpoint of further suppressing the detachment of the insulating particles and further improving the insulation reliability and the conduction reliability of the connection structure, it is preferable that the insulating particles are not formed by the friction generated by the mixing. The best is that the blending method is not used.

When the insulating particles are obtained, the polymer compound or the compound which is the polymer is preferably used in an amount of 30 parts by weight or more, more preferably 50 parts by weight or more, based on 100 parts by weight of the insulating particles. It is preferably 500 parts by weight or less, more preferably 300 parts by weight or less. When the amount of the polymer compound used is at least the above lower limit and not more than the above upper limit, a favorable layer can be formed.

Examples of specific production conditions of the layer formed by the above polymer compound include the following production conditions.

First, in an amount of 100 to 500 parts by weight of a solvent such as water, 1 to 3 parts by weight of an insulating particle body having a reactive functional group on the surface, and 0.1 to 20 parts by weight of a compound having a reactive double bond and a hydroxyl group (preferably 0.1 to 1 part by weight), 0.01 to 5 parts by weight of the crosslinking agent (preferably 0.01 to 1 part by weight), 0.1 to 5 parts by weight of the dispersing agent (preferably 0.1 to 3 parts by weight), and thermal polymerization. The starting agent is 0.1 to 5 parts by weight (preferably 0.1 to 3 parts by weight). Next, the temperature was raised to the reaction temperature of the thermal polymerization initiator in an oil bath while stirring by a tri-motor, polymerization was started, and the reaction was carried out for 5 hours or more. Thereafter, the unreacted compound was removed using a centrifugal separator to obtain insulating particles covering the surface of the insulating particle body with the above layer.

Examples of the method of attaching the insulating particles to the surface of the conductive particles and the conductive layer include a chemical method, a physical or mechanical method, and the like. Examples of the above chemical method include an interfacial polymerization method, a suspension polymerization method in the presence of particles, and an emulsion polymerization method. Examples of the physical or mechanical method include a method of spray drying, mixing, electrostatic adhesion, spraying, dipping, and vacuum evaporation. Among them, in the hybrid method, there is a tendency that the insulating particles are likely to be detached. Therefore, a method of adhering the insulating particles to the surface of the conductive particles and the conductive layer is preferably a method other than the mixing method. Among them, from the viewpoint that the insulating particles are hard to be separated, a method of adhering the insulating particles to the surface of the conductive layer via a chemical bond is preferred.

In the conductive particles with insulating particles of the present invention, it is preferred that the insulating particles are not adhered to the surface of the conductive particles by a mixing method.

Further, as shown in Fig. 6, in the conductive particles 101 with the insulating particles previously attached by the hybrid method, the portion 102b other than the portion 102a of the insulating particles 103 is adhered to the surface of the conductive particles 102. A polymer compound 104 is also attached. This is because, in the hybrid method, a compressive shear force is applied to repeatedly cause adhesion and detachment of the insulating particles, and the insulating particles are gradually adhered. The layer formed of the polymer compound is peeled off by the compressive shear force, and the peeled polymer compound adheres to a portion other than the portion of the conductive particle to which the insulating particle adheres. The polymer compound adhering to a portion of the surface of the conductive particle to which the insulating particle is adhered can increase the volume resistivity of the conductive particle and reduce the connection resistance between the electrodes. Further, even when the surface of the conductive particles 101 with insulating particles shown in FIG. 6 is coated by a film, the conductivity is also lowered, and the connection resistance between the electrodes is also likely to be low.

An example of a method of adhering the insulating particles to the surface of the conductive particles and the conductive layer is as follows.

First, conductive particles are placed in 3 L of a solvent such as water, and the insulating particles are gradually added while stirring. After sufficiently stirring, the conductive particles with the insulating particles are separated and dried by a vacuum dryer or the like to obtain conductive particles with insulating particles.

The conductive layer preferably has a reactive functional group capable of reacting with the insulating particles on the surface, and preferably has a reactive functional group reactive with the coating film. The insulating particles preferably have a reactive functional group capable of reacting with the conductive layer on the surface, and preferably have a reactive functional group reactive with the coating. The coating film preferably has a reactive functional group capable of reacting with the conductive layer on the surface, and preferably has a functional group reactive with the insulating particles. Due to these reactive functional groups, the insulating particles are unexpectedly difficult to be detached from the surface of the conductive particles, and the film is less likely to be peeled off from the surface of the conductive particles and the surface of the insulating particles. Further, the surface of the conductive layer can be sufficiently covered by the film, and the surface of the insulating particles can be sufficiently covered by the film.

As the above reactive functional group, a suitable group can be selected in consideration of reactivity. Examples of the reactive functional group include a hydroxyl group, a vinyl group, and an amine group. In order to make the reactivity excellent, the above reactive functional group is preferably a hydroxyl group. It is preferable that the conductive particles having the insulating particles have a hydroxyl group in at least a part of the surface of the surface. It is preferred that the conductive particles have a hydroxyl group on the surface. It is preferred that the insulating particles have a hydroxyl group on the surface. It is preferred that the above film has a hydroxyl group on the surface.

When the surface of the insulating particles and the surface of the conductive particles have a hydroxyl group, the adhesion between the insulating particles and the conductive particles is moderately increased by the dehydration reaction.

The compound having a hydroxyl group may, for example, be a compound containing a P-OH group or a compound containing a Si-OH group. Examples of the compound having a hydroxyl group to introduce a hydroxyl group into the surface of the insulating particles include a compound containing a P-OH group and a compound containing a Si-OH group.

Specific examples of the P-OH group-containing compound include acid phosphoxy ethyl methacrylate, dihydrogen propyl methacrylate, and dihydrogen phosphate. Alcohol monomethacrylate and dihydrogen phosphate polypropylene glycol monomethacrylate. The compound containing a P-OH group may be used alone or in combination of two or more.

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

For example, insulating particles having a hydroxyl group on the surface can be obtained by treatment with a decane coupling agent. Examples of the decane coupling agent include hydroxytrimethoxydecane and the like.

(Manufacturing method of conductive particles with insulating particles)

In the method for producing conductive particles with insulating particles according to the present invention, a compound having a carbon number of 6 to 22 (compound A) is used on the surface of the conductive particle body to which the insulating particles are attached. The coating film is formed so as to coat the surface of the conductive particle body to which the insulating particles are attached.

The method of forming a coating film on the surface of the conductive particle body with the insulating particles by using the above-mentioned compound A is not particularly limited, and the solution containing the compound A described above is adhered to the conductivity with insulating particles. The method of the surface of the particle body, etc.

The solvent in the solution containing the above compound A is preferably water. The solvent in the solution containing the above compound A may also contain an organic solvent such as tetrahydrofuran or an alcohol such as methanol, ethanol or propanol. After the solution is attached to the surface of the conductive particle body to which the insulating particles are attached, the solvent is removed as needed.

The content of the above compound A in the solution containing the above compound A can be appropriately adjusted to obtain a desired film. In 100% by weight of the solution containing the above compound A, it is preferred that the content of the above compound A is in the range of 0.5 to 3% by weight.

For example, when a reactive functional group reactive with the above compound A is present on the surface of the conductive layer or the surface of the insulating particle, the reactive functional group may be reacted with the above compound A to chemically bond the above compound A to the above. The surface of the conductive layer and the surface of the insulating particles.

It is preferable that the conductive particles having the insulating particles have a hydroxyl group in at least a part of the surface of the surface, and a compound having a hydroxyl group having an alkyl group having 6 to 22 carbon atoms (hereinafter also referred to as a compound A1) is attached thereto. The hydroxyl group on the surface of the conductive particle body of the insulating particles reacts to form a coating film so as to coat the surface of the conductive particle body with the insulating particles. Further, it is preferable that the conductive particles have a hydroxyl group on the surface, and the compound A1 reacts with the hydroxyl group on the surface of the conductive particles to form a coating film so as to coat the surface of the conductive particle body to which the insulating particles are attached. It is preferable that the insulating particles have a hydroxyl group on the surface, and the compound A1 reacts with the hydroxyl group on the surface of the insulating particles to form a coating film so as to coat the surface of the conductive particle body with the insulating particles. Further, it is preferable that the surface of the conductive particles and the surface of the insulating particles each have a hydroxyl group, and the compound A1 reacts with the surface of the conductive particles and the hydroxyl group on the surface of the insulating particles to coat the insulating particles. A film is formed in such a manner as to form a surface of the conductive particle body. By forming the film in such a preferred manner, the surface of the conductive layer can be sufficiently covered by the film, and the surface of the insulating particles can be sufficiently covered by the film. Therefore, it is further difficult to generate rust on the conductive layer, and the film becomes difficult to peel off, and the insulating particles are unexpectedly difficult to be detached.

(Anisotropic conductive material)

The anisotropic conductive material of the present invention comprises the conductive particles and the binder resin with insulating particles of the present invention, or the insulating property obtained by the method for producing the conductive particles with insulating particles of the present invention. Conductive particles of particles and binder resin.

When the conductive particles having the insulating particles are used, the surface of the insulating particles and the conductive particles are coated with the coating film. Therefore, when the conductive particles with the insulating particles are dispersed in the adhesive resin, The insulating particles are less likely to be detached from the surface of the conductive particles.

The above binder resin is not particularly limited. As the above-mentioned binder resin, an insulating resin is usually used. Examples of the above-mentioned binder resin include an ethylene resin, a thermoplastic resin, a curable resin, a thermoplastic block copolymer, and an elastomer. The above-mentioned adhesive resin may be used alone or in combination of two or more.

Examples of the vinyl resin include a vinyl acetate resin, an acrylic resin, and a styrene resin. Examples of the thermoplastic resin include a polyolefin resin, an ethylene-vinyl acetate copolymer, and a polyamide resin. Examples of the curable resin include an epoxy resin, an amine ester resin, a polyimide resin, and an unsaturated polyester resin. Further, the curable resin may be a room temperature curing resin, a thermosetting resin, a photocurable resin or a moisture curing resin. The curable resin may be used in combination with a curing agent. Examples of the above thermoplastic block copolymer include a styrene-butadiene-styrene block copolymer, a styrene-isoprene-styrene block copolymer, and a styrene-butadiene-styrene block. a hydride of a segment copolymer, a hydride of a styrene-isoprene-styrene block copolymer, and the like. Examples of the elastomer include styrene-butadiene copolymer gum and acrylonitrile-styrene block copolymer gum.

The anisotropic conductive material may contain, for example, a filler, a bulking agent, a softening agent, a plasticizer, a polymerization catalyst, a curing catalyst, and a coloring, in addition to the conductive particles with insulating particles and the above-mentioned binder resin. Various additives such as agents, antioxidants, heat stabilizers, light stabilizers, ultraviolet absorbers, lubricants, static inhibitors, and flame retardants.

The method of dispersing the above-mentioned conductive particles containing the insulating particles in the above-mentioned binder resin can be carried out by a conventionally known dispersion method, and is not particularly limited. In the method of dispersing the conductive particles with the insulating particles in the binder resin, for example, the conductive particles having the insulating particles added to the binder resin are kneaded by a planetary mixer or the like. The method of dispersing the conductive particles with insulating particles uniformly dispersed in water or an organic solvent using a homogenizer or the like, and then adding them to the binder resin, and kneading them by a planetary mixer or the like to disperse them. And a method in which the binder resin is diluted with water or an organic solvent, and the conductive particles with insulating particles are added and kneaded by a planetary mixer or the like to be dispersed.

The anisotropic conductive material of the present invention can be used as an anisotropic conductive paste or an anisotropic conductive film. When the anisotropic conductive material of the present invention is used as an anisotropic conductive film, a film containing no conductive particles may be laminated on the anisotropic conductive film containing the conductive particles.

The anisotropic conductive material of the present invention is preferably an anisotropic conductive paste. The anisotropic conductive paste is excellent in usability and circuit filling property. When the anisotropic conductive paste is obtained, although the conductive particles having the insulating particles are relatively large, the insulating particles are prevented from being detached from the surface of the conductive particles by the presence of the coating.

The content of the above-mentioned binder resin is preferably in the range of 10 to 99.99% by weight based on 100% by weight of the anisotropic conductive material. The content of the binder resin is more preferably 30% by weight or more, still more preferably 50% by weight or more, particularly preferably 70% by weight or more, and more preferably 99.9% by weight or more. When the content of the binder resin is not less than the above lower limit and not more than the above upper limit, the conductive particles having the insulating particles can be efficiently disposed between the electrodes, and the connecting member to be connected by the anisotropic conductive material can be further improved. Continuity reliability.

In 100% by weight of the anisotropic conductive material, the content of the conductive particles with insulating particles is preferably in the range of 0.01 to 20% by weight. The content of the conductive particles having the insulating particles thereon is more preferably 0.1% by weight or more, still more preferably 20% by weight or less, and still more preferably 15% by weight or less. When the content of the conductive particles with the insulating particles is not less than the above lower limit and not more than the above upper limit, the conduction reliability between the electrodes can be further improved.

(connection structure)

The connection member can be connected by using the conductive particles with insulating particles of the present invention or by using an anisotropic conductive material containing the conductive particles with insulating particles and an adhesive resin, thereby obtaining a connection structure. body. Further, the conductive particles with insulating particles obtained by the method for producing conductive particles with insulating particles of the present invention or the conductive particles containing the insulating particles and the adhesive resin are used. The conductive material is connected to the connection target member, whereby the connection structure can be obtained.

The connection structure includes a first connection target member, a second connection target member, and a connection portion that electrically connects the first and second connection target members. Preferably, the connection portion is provided with the insulating particles described above. The conductive particles are formed or a connection structure formed of the anisotropic conductive material containing the conductive particles with insulating particles and the binder resin. In the case of using conductive particles with insulating particles, the connecting portion itself is formed of conductive particles with insulating particles. In other words, the first and second connection target members are electrically connected by the conductive particles in the conductive particles with the insulating particles.

Fig. 5 is a cross-sectional view schematically showing a connection structure in which the conductive particles 1 with insulating particles shown in Fig. 1 are used.

The connection structure 51 shown in FIG. 5 includes a first connection target member 52, a second connection target member 53, and a connection portion 54 that connects the first and second connection target members 52 and 53. The connecting portion 54 is formed of an anisotropic conductive material containing conductive particles 1 with insulating particles and a binder resin. In FIG. 5, for the convenience of illustration, the conductive particles 1 with insulating particles are shown in a schematic manner. In addition to the conductive particles 1 with insulating particles, conductive particles 21, 41, and 61 with insulating particles may be used.

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

The method for producing the above-described connection structure is not particularly limited. An example of the manufacturing method of the connection structure is that the anisotropic conductive material is disposed between the first connection target member and the second connection target member, and after the laminate is obtained, the laminate is heated and pressurized. Method, etc. The pressure of the above pressurization is about 9.8 × 10 ⁴ to 4.9 × 10 ⁶ Pa. The heating temperature is about 120 to 220 °C.

When the laminated body is heated and pressurized, the insulating particles 15 existing between the conductive particles 11 and the electrodes 52b and 53b can be excluded. For example, during the heating and pressurization, the insulating particles 15 existing between the conductive particles 11 and the electrodes 52b and 53b are melted and deformed, and the surface of the conductive particles 11 is partially exposed. Further, since a large force is applied during the heating and pressurization, a part of the insulating particles 15 are peeled off from the surface of the conductive particles 11, and the surface of the conductive particles 11 is partially exposed. Since the exposed portion of the surface of the conductive particles 11 is in contact with the electrodes 52b and 53b, the electrodes 52b and 53b can be electrically connected via the conductive particles 11.

Specific examples of the connection target member include electronic components such as a semiconductor wafer, a capacitor, and a diode, and electronic components such as a printed circuit board, a flexible printed circuit board, and a circuit board such as a glass substrate. It is preferable that the anisotropic conductive material is in the form of a paste and is applied to the member to be joined in the state of a paste. The conductive particles and the anisotropic conductive material with the insulating particles are preferably used for connection as a connection target member of the electronic component.

In particular, the conductive particles with insulating particles of the present invention can be suitably used for a COG in which a glass substrate and a semiconductor wafer are connected to each other, or a FOG in which a glass substrate and a flexible printed circuit (FPC) are connected components. in. The conductive particles with insulating particles of the present invention can be used in COG or in FOG. In the connection structure of the present invention, the first and second connection target members are preferably a glass substrate and a semiconductor wafer, or a glass substrate and a flexible printed circuit board. The first and second connection target members may be a glass substrate or a semiconductor wafer, or may be a glass substrate or a flexible printed circuit board.

It is preferable to provide a bump in a semiconductor wafer used in a COG in which a glass substrate and a semiconductor wafer are connected components. The bump size is preferably an electrode area of 1000 μm ² or more and 10000 μm ² or less. The electrode space in the semiconductor wafer provided with the bump (electrode) is preferably 30 μm or less, more preferably 20 μm or less, and still more preferably 10 μm or less. In such a COG use, the conductive particles with insulating particles of the present invention can be suitably used. In the FPC used for the FOG in which the glass substrate and the flexible printed circuit board are connected to each other, the electrode space is preferably 30 μm or less, and more preferably 20 μm or less.

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

Hereinafter, the present invention will be specifically described by way of examples and comparative examples. The invention is not limited to the following examples.

(Example 1)

Conductive particles having a metal layer on which a nickel plating layer was formed on the surface of the divinylbenzene resin particles (having an average particle diameter of 3.01 μm and a thickness of the conductive layer of 0.2 μm) were prepared.

Further, the surface of the cerium oxide particles (having an average particle diameter of 200 nm) prepared by a sol-gel method was coated with hydroxytriethoxydecane to obtain insulating particles having a hydroxyl group on the surface. This insulating particle was dispersed in 30 mL of pure water to obtain a dispersion liquid containing insulating particles.

250 mL of pure water, 50 mL of ethanol, and 15 parts by weight of the above-mentioned conductive particles were placed in a 1 L separable flask and sufficiently stirred to obtain a liquid containing conductive particles. In the liquid containing the conductive particles, a dispersion containing insulating particles was dropped over 10 minutes while applying ultrasonic waves. Thereafter, the mixture was filtered, and dried at 100 ° C for 8 hours by a vacuum dryer to obtain a conductive particle body with insulating particles.

10 parts by weight of the above-mentioned electrically conductive particle body with insulating particles and 0.5 part by weight of monohexyl phosphate were placed in a mixture of 25 g of pure water and 25 g of ethanol, and the mixture was stirred at 50 ° C for 1 hour. Thereafter, the mixture was filtered, and dried at 100 ° C for 8 hours in a vacuum dryer to obtain a coating having a film formed of the above-mentioned monohexyl phosphate on the surface of the conductive particle body having the insulating particles. Conductive particles having insulating particles. The coating film covers the surface of the conductive particles and the surface of the insulating particles. The coating portion covering the surface of the conductive particles is connected to the coating portion covering the surface of the insulating particles.

(Example 2)

The same conductive particles as in Example 1 (having an average particle diameter of 3.01 μm and a thickness of the conductive layer of 0.2 μm) were prepared.

Further, a surface of a cerium oxide particle (having an average particle diameter of 200 nm) prepared by a sol-gel method was coated with vinyl triethoxysilane, and an insulating particle having a vinyl group on the surface was obtained as an insulating particle. Ontology.

One part by weight of the above-mentioned insulating particle body, 0.22 parts by weight of methacrylic acid, 0.05 parts by weight of ethylene glycol dimethacrylate, and an initiator (Wako Pure Chemicals) were sufficiently stirred by a three-one motor in 200 mL of water. 0.5 parts by weight of "V-50" manufactured by Industrial Co., Ltd. was heated to 70 ° C while being heated at 70 ° C for 6 hours to polymerize the above monomers.

Thereafter, the mixture was cooled, and subjected to solid-liquid separation twice by a centrifugal separator, and excess monomer was removed by washing to obtain insulating particles coated with a polymer compound on the entire surface. Next, the obtained insulating particles were dispersed in 30 mL of pure water to obtain a dispersion of insulating particles.

250 mL of pure water, 50 mL of ethanol, and 15 parts by weight of the above-mentioned conductive particles were placed in a 1 L separable flask and sufficiently stirred to obtain a liquid containing conductive particles. In the liquid containing the conductive particles, the dispersion of the insulating particles was dropped on the surface for 10 minutes while applying ultrasonic waves, and the mixture was heated to 40 ° C and stirred for 1 hour. Thereafter, the mixture was filtered, and dried at 100 ° C for 8 hours by a vacuum dryer to obtain a conductive particle body with insulating particles.

Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the obtained conductive particles having the insulating particles were used. The coating film covers the surface of the conductive particles and the surface of the insulating particles. The coating portion covering the surface of the conductive particles is connected to the coating portion covering the surface of the insulating particles.

(Example 3)

10 g of the resin particles were etched and then washed with water. Next, palladium sulfate is added to the resin particles to adsorb palladium ions on the resin particles. The resin particles to which palladium adhered were stirred in 300 mL of ion-exchanged water for 3 minutes, and dispersed to obtain a dispersion. Then, 1 g of a metal nickel particle slurry ("2020SUS" manufactured by Mitsui Metals Co., Ltd., average particle diameter: 200 nm) was added to the dispersion liquid for 3 minutes to obtain resin particles to which a core substance adhered. On the surface of the resin particles to which the core material is attached, a nickel layer is formed by electroless nickel plating. In this way, the core particles are adhered to the surface of the resin particles, and the conductive particles are coated with the nickel particles on the surface of the resin particles and the core material. The conductive particles had an average particle diameter of 3.02 μm and the conductive layer had a thickness of 0.2 μm. The conductive particles have protrusions on the surface.

Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the obtained conductive particles were used.

(Example 4)

Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the monohexyl phosphate was changed to the monooctyl phosphate.

(Example 5)

Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the monohexyl phosphate was changed to monododecyl phosphate.

(Example 6)

Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the monohexyl phosphate was changed to monohexadecyl phosphate.

(Example 7)

Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the monohexyl phosphate was changed to hexyltriethoxydecane.

(Example 8)

Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the monohexyl phosphate was changed to octyltriethoxydecane.

(Example 9)

Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the monohexyl phosphate was changed to dodecyltriethoxydecane.

(Embodiment 10)

Production of insulating particles:

The surface of the cerium oxide particles (having an average particle diameter of 200 nm) prepared by a sol-gel method is coated with vinyl triethoxy decane to obtain insulating particles having a reactive functional group, that is, a vinyl group. As the insulating particle body. Specifically, 10 parts by weight of cerium oxide particles were dispersed in 400 mL of a liquid obtained by mixing water and ethanol in a weight ratio of 1:9 using a tri-motor to obtain a first dispersion liquid. Next, 0.1 part by weight of vinyltriethoxysilane was dispersed in 100 mL of a liquid obtained by mixing water and ethanol in a weight ratio of 1:9 to obtain a second dispersion. Thereafter, the second dispersion liquid was added dropwise to the first dispersion liquid over 10 minutes to obtain a mixed liquid. After the dropwise addition, the resulting mixture was stirred for 30 minutes. Thereafter, the mixed solution was filtered, dried at 100 ° C for 2 hours, and then sieved through a sieve to obtain an insulating particle body.

1 part by weight of the above-mentioned insulating particles, 2 parts by weight of methacrylic acid as a compound of a polymer compound, and 1 part by weight of ethylene glycol dimethacrylate as a compound of a polymer compound were added to 200 mL of water. 0.5 parts by weight of the initiator ("V-50" manufactured by Wako Pure Chemical Industries, Ltd.), and 1 part by weight of polyoxyethylene lauryl ether ("EMULGEN 106" manufactured by Kao Corporation) as an emulsifier, using an ultrasonic irradiation machine Make it fully emulsified. Thereafter, the mixture was heated to 70 ° C while being sufficiently stirred by a tri-motor, and kept at 70 ° C for 6 hours to polymerize the above monomers.

Thereafter, the mixture was cooled, and subjected to solid-liquid separation twice by a centrifugal separator, and the excess monomer was removed by washing to obtain insulating particles coated with the polymer compound on the entire surface. Next, the obtained insulating particles were dispersed in 30 mL of pure water to obtain a dispersion liquid containing insulating particles. Further, in the state of the dispersion of the insulating particles, the average particle diameter of the insulating particles coated with the polymer compound was 324 nm.

Production of conductive particles with insulating particles:

Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the dispersion liquid containing the obtained insulating particles was used as the dispersion liquid containing the insulating particles.

(Example 11)

A dispersion liquid containing insulating particles was obtained in the same manner as in Example 10 except that the compound of the polymer compound was changed to 2.5 parts by weight of methacrylic acid and 1.2 parts by weight of divinylbenzene. Further, in the state of the dispersion of the insulating particles, the insulating particles coated with the polymer compound have an average particle diameter of 335 nm.

Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the dispersion liquid containing the obtained insulating particles was used as the dispersion liquid containing the insulating particles.

(Embodiment 12)

The surface of the cerium oxide particles is coated with methacryloxypropyltriethoxy decane to obtain insulating particles having a methacryl fluorenyl group on the surface as an insulating particle body, and a compound to be a polymer compound. A dispersion liquid containing insulating particles was obtained in the same manner as in Example 10 except that the amount was changed to 2.2 parts by weight of vinyl acetate and 1.0 part by weight of N,N-methylenebisacrylamide.

In addition, in the case of obtaining the main body of the insulating particles, 10 parts by weight of cerium oxide particles and 0.1 parts by weight of methacryloxypropyltriethoxy decane were used, except that the same method as in Example 10 was used. The insulating particle body is obtained. Further, in the state of the dispersion of the insulating particles, the average particle diameter of the insulating particles coated with the polymer compound was 326 nm.

Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the dispersion liquid containing the obtained insulating particles was used as the dispersion liquid containing the insulating particles.

(Example 13)

As the conductive particles, nickel powder (100 nm) as a core material is adhered to the surface of the divinylbenzene resin particles, and a nickel plating layer is formed on the surface of the divinylbenzene particles to which the nickel powder is adhered. Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the conductive particles (the average particle diameter of 3.03 μm and the thickness of the conductive layer were 0.21 μm) were used.

(Example 14)

A dispersion liquid containing insulating particles was obtained in the same manner as in Example 10 except that the compound of the polymer compound was changed to 0.4 parts by weight of methacrylic acid and 0.05 parts by weight of ethylene glycol dimethacrylate.

Further, in the state of the dispersion of the insulating particles, the average particle diameter of the insulating particles coated with the polymer compound was 248 nm.

Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the dispersion liquid containing the obtained insulating particles was used as the dispersion liquid containing the insulating particles.

(Example 15)

Conductive particles with insulating particles were obtained in the same manner as in Example 2 except that the main body of the conductive particles having the insulating particles was obtained by the mixing method.

(Comparative Example 1)

Conductive particles with insulating particles attached to the main body of the conductive particles with insulating particles obtained in Example 1. That is, in Comparative Example 1, the coating film was not formed on the main body of the conductive particles having the insulating particles obtained in Example 1, and the conductive particle body with the insulating particles obtained in Example 1 was obtained. The following was used as the conductive particles with insulating particles.

(Comparative Example 2)

Conductive particles with insulating particles attached to the main body of the conductive particles with insulating particles obtained in Example 2. That is, in Comparative Example 2, the coating film was not formed on the main body of the conductive particles having the insulating particles obtained in Example 2, and the conductive particle body with the insulating particles obtained in Example 2 was obtained. The following was used as the conductive particles with insulating particles.

(Comparative Example 3)

Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the monohexyl phosphate was changed to monopentyl phosphate (the carbon number of the alkyl group was 5).

(Comparative Example 4)

Conductive particles with insulating particles were obtained in the same manner as in Example 1 except that the monohexyl phosphate was changed to the mono-trisyl phosphate (the carbon number of the alkyl group was 23).

(Evaluation)

(1) Evaluation of the content of phosphorus or antimony in conductive particles with insulating particles

1 part by weight of the conductive particles with insulating particles of the examples and the comparative examples was placed in a 5% by weight aqueous solution of citric acid (a liquid in which 5% by weight of citric acid was dissolved in 95% by weight of water) 100 parts by weight Thereafter, the mixture was stirred at 40 ° C for 30 minutes, and after obtaining a treatment liquid, the treatment liquid was filtered through a filter paper to obtain a filtrate. In the conductive particles with insulating particles of Examples 1 to 9, after the treatment with the citric acid aqueous solution, the film adhered to the surface of the conductive particle body with the insulating particles is peeled off.

The content of the phosphorus element or the lanthanum element in the obtained filtrate was measured using an ICP luminescence analyzer ("ULTIMA2" manufactured by Horiba, Ltd.).

(2) Production of connection structure

The electrically conductive particles with the insulating particles of the examples and the comparative examples were added to "STRUCTBOND XN-5A" manufactured by Mitsui Chemicals Co., Ltd. at a content of 10% by weight, and dispersed to obtain anisotropic conductivity. paste.

A transparent glass substrate having an ITO electrode pattern of L/S of 30 μm/30 μm was formed on the upper surface. Further, a semiconductor wafer having a copper electrode pattern having an L/S of 30 μm/30 μm was formed on the lower surface.

The obtained anisotropic conductive paste was applied onto the above transparent glass substrate to have a thickness of 30 μm to form an anisotropic conductive paste layer. Next, the semiconductor wafer is laminated on the anisotropic conductive paste layer so that the electrodes face each other. Thereafter, the temperature of the head was adjusted so that the temperature of the anisotropic conductive paste layer was 185 ° C, and a pressure heating head was placed on the upper surface of the semiconductor wafer, and a pressure of 1 MPa was applied to make the anisotropic conductive paste layer. It was completely hardened at 185 ° C to obtain a joined structure.

(3) Conduction evaluation (between upper and lower electrodes)

The connection resistance between the lower electrodes on the obtained connection structure was measured by a four-terminal method. Calculate the average of the two connection resistances. Furthermore, the connection resistance can be obtained by measuring the voltage at which a fixed current flows in accordance with the relationship of voltage=current×resistance. The average value of the connection resistance is 2.0 Ω or less, and the case where the polymer compound is not adhered to the portion other than the portion where the insulating particles adhere to the surface of the conductive particle is referred to as “○”; 2 Ω or less, in the case where the portion where the insulating particles are adhered to the surface of the conductive particles is present, the case where the polymer compound is adhered is referred to as "Δ"; and the average value of the connection resistance exceeds 2 Ω. For "X", the results are shown in Table 1 below.

(4) Insulation evaluation (between electrodes adjacent in the lateral direction)

In the obtained connected structure, the presence or absence of electric leakage between adjacent electrodes was evaluated by measuring resistance with a tester. When the resistance exceeds 500 MΩ, it is judged that there is no leakage, and the result is indicated as "○". When the resistance is 500 MΩ or less, it is judged that there is leakage and the result is indicated as "x", as shown in Table 1 below. in.

(5) Rust prevention evaluation

The connection structure produced in the above insulation evaluation was placed under conditions of 85 ° C and a relative humidity of 85%. The connection resistance between the electrodes was measured by a four-terminal method in the same manner as described above after the start of the standing. Compared with the average value of the connection resistance (before placement) in the above-mentioned conduction evaluation, the case where the average value of the connection resistance (after placement) is less than 150% is referred to as "○", and the connection resistance (after placement) is used. The case where the average value was increased by 150% or more was referred to as "x", and the results are shown in Table 1 below.

The results are shown in Table 1 below.

As shown in the above Table 1, in the rust-proof evaluation using the conductive particles with insulating particles of Comparative Examples 1 and 2, the resistance value increased by 150% or more. The reason is that rust is generated on the surface of the conductive layer.

Further, in the conductive particles having the insulating particles in the examples 1 to 14, it was confirmed that the polymer compound was not adhered to the portion other than the portion where the insulating particles adhered to the surface of the conductive particles. In addition, in the fifteenth embodiment, since the physical/mechanical compounding method is used, a portion other than the portion where the insulating particles are adhered to the surface of the conductive particles is where the polymer compound adheres. As described above, when a polymer compound is adhered to a portion other than the portion where the insulating particles are adhered to the surface of the conductive particles, the conduction reliability may be lowered depending on the case.

(6) Disengagement of insulating particles

Moreover, in the anisotropic conductive paste obtained by the insulation evaluation, it was observed whether the insulating particles were detached from the surface of the conductive particles.

As a result, in the anisotropic conductive pastes using the conductive particles of the insulating particles of Examples 1 to 15, the anisotropic conductive particles using the conductive particles with insulating particles of Comparative Examples 1 and 2 were used. In comparison with the paste, the ratio of the insulating particles which are separated from the surface of the conductive particles is extremely small. In particular, in the anisotropic conductive paste using the conductive particles with insulating particles of Example 1, compared with the anisotropic conductive paste using the conductive particles with insulating particles of Comparative Example 1 The proportion of insulating particles that are detached from the surface of the conductive particles is extremely small. Further, in the anisotropic conductive paste using the conductive particles with insulating particles of Example 2, compared with the anisotropic conductive paste using the conductive particles with insulating particles of Comparative Example 2 The proportion of insulating particles that are detached from the surface of the conductive particles is extremely small. The reason for this is considered to be that the coating film is formed in the conductive particles having the insulating particles in Examples 1 to 15, and thus the separation of the insulating particles is suppressed.

Further, in the anisotropic conductive paste using the conductive particles with insulating particles of Example 2, the anisotropic conductive paste using the conductive particles with insulating particles of Example 1 is used. The proportion of insulating particles that are detached from the surface of the conductive particles is small. The reason for this is considered to be that, in the insulating particles of the second embodiment, since the surface of the insulating particles is coated with a soft layer formed of a polymer compound, the separation of the insulating particles is suppressed.

1, 21, 41, 61, 101. . . Conductive particles with insulating particles

2, 22, 42, 62. . . Conductive particle body with insulating particles

3, 23. . . Laminating

11, 31, 71, 102. . . Conductive particles

12. . . Substrate particle

13, 32, 76. . . Conductive layer

15, 35, 45, 103. . . Insulating particles

33. . . Core material

34, 77. . . Protrusion

45a. . . Insulating particle body

45b. . . Floor

51. . . Connection structure

52. . . First connection object part

52a. . . Upper surface

52b, 53b. . . electrode

53. . . Second connection object part

53a. . . lower surface

54. . . Connection

76a. . . First conductive layer

76b. . . Second conductive layer

102a. . . a portion of the surface of the conductive particle 102 to which the insulating particle 103 is attached

102b. . . A portion other than the portion 102a of the insulating particles 103 adhered to the surface of the conductive particles 102

104. . . Polymer compound

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

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

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

Fig. 4 is a cross-sectional view showing conductive particles with insulating particles according to a fourth embodiment of the present invention.

Fig. 5 is a front cross-sectional view schematically showing a connection structure in which conductive particles having insulating particles shown in Fig. 1 are used.

Fig. 6 is a cross-sectional view showing conductive particles with insulating particles attached previously using a hybrid method.

1. . . Conductive particles with insulating particles

2. . . Conductive particle body with insulating particles

3. . . Laminating

11. . . Conductive particles

12. . . Substrate particle

13. . . Conductive layer

15. . . Insulating particles

Claims (10)

A conductive particle having insulating particles, comprising: a conductive particle body having insulating particles; the conductive particles having a conductive layer at least on a surface thereof; and insulating particles attached to a surface of the conductive particle And a film covering the surface of the main body of the conductive particles having the insulating particles; the film is formed of a compound having an alkyl group having 6 to 22 carbon atoms; and the insulating particles are bonded to each other via chemical bonding a surface of the conductive layer; the coating film comprising a coating portion covering the surface of the conductive particle and a coating portion covering the surface of the insulating particle; and a coating portion covering the surface of the conductive particle and covering the surface of the insulating particle The film portions are connected. The conductive particles of the insulating material according to claim 1, wherein the insulating particles comprise inorganic particles. The electroconductive particle which has the insulating particle attached to Claim 1 or 2, wherein the said compound which has the alkyl group of C6-22 is selected from the phosphate ester or its salt, a phosphite or its salt, and an alkoxy group. At least one of the group consisting of decane, alkyl mercaptan and dialkyl disulfide. The conductive particles according to claim 1 or 2, wherein the insulating particles have an insulating particle body and a layer formed of a polymer compound covering at least a part of a surface of the insulating particle body. . In the conductive particles in which the insulating particles are attached, the polymer compound is not adhered to a portion other than the portion of the conductive particles on which the insulating particles are adhered. The conductive particle according to claim 4, wherein the polymer compound has at least one reactive functional group selected from the group consisting of a (meth) acrylonitrile group, a glycidyl group, and a vinyl group. . The conductive particles with insulating particles attached to claim 1 or 2, wherein the insulating particles are not attached to the surface of the conductive particles by a mixing method. An anisotropic conductive material comprising: the conductive particles with insulating particles according to any one of claims 1 to 7, and a binder resin. An anisotropic conductive material according to claim 8, which is an anisotropic conductive paste. A connection structure comprising: a first connection target member, a second connection target member, and a connection portion that connects the first and second connection target members; wherein the connection portion is any one of claims 1 to 7 It is formed of conductive particles with insulating particles or an anisotropic conductive material containing the conductive particles with insulating particles and a binder resin.