JP2013125858A - Connection method, connection structure, anisotropic conductive film and method for producing the anisotropic conductive film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a connection method achieving excellent repairability and connection reliability; a connection structure comprising a substrate and an electronic component connected by the connection method; and an anisotropic conductive film and a method for producing the anisotropic conductive film.SOLUTION: In an anisotropic conductive film 1, an insulating adhesive layer 13 includes insulating particles 13b projecting from a surface thereof. A ratio of a length (projecting ratio) projecting from the surface of the insulating adhesive layer 13 in each insulating particle 13b relative to an average particle size of the insulating particles 13b is in a range of 30-60%, and a 10% K value of each of the insulating particles 13b is 4,000 N/mmor less. The surface from which the insulating particles 13b in the insulating adhesive layer 13 project and a connection surface where a wiring electrode 15 on a glass substrate 14 is formed are confronted with each other to temporally stick the anisotropic conductive film 1 on the glass substrate 14.

Description

  The present invention relates to a connection method for connecting a substrate and an electronic component, a connection structure connected by the connection method, an anisotropic conductive film used for the connection method, and a method for manufacturing the same.

  Conventionally, there is a method of connecting a connection surface on which a wiring electrode of a substrate is formed and a connection surface on which a terminal electrode (bump) of an electronic component is formed through an anisotropic conductive film (ACF). . In the connection method using the anisotropic conductive film, the anisotropic conductive film is temporarily attached on the connection surface of the substrate, and the anisotropic conductive film and the connection surface of the electronic component are opposed to each other on the anisotropic conductive film. An electronic component is placed on and heat-pressed. Thereby, the electroconductive particle in an anisotropic conductive film is inserted | pinched between the terminal electrode of an electronic component, and the wiring electrode of a board | substrate, and is crushed. As a result, the terminal electrode of the electronic component and the wiring electrode of the substrate are electrically connected via the conductive particles.

  Conductive particles that are not between the terminal electrode and the wiring electrode exist in the insulating adhesive composition of the anisotropic conductive film, and maintain an electrically insulated state. That is, electrical continuity is achieved only between the terminal electrode and the wiring electrode.

  In the connection method using such an anisotropic conductive film, the process which temporarily sticks an anisotropic conductive film to a board | substrate is normally performed. And when the malfunction has arisen in the position state of the anisotropic conductive film after temporary sticking, the repair process which removes an anisotropic conductive film and temporarily sticks again is performed.

  Various methods for imparting repair properties to anisotropic conductive films have been proposed. For example, in Patent Document 1, when an acrylic particle is added to an adhesive to provide repair properties and the adhesive adhered to the circuit board is removed, a solvent having an SP value of 8 to 12 is applied to the adhesive. This describes a technique for removing adhesive residues by causing acrylic particles to swell or dissolve.

  For example, Patent Document 2 includes a conductive particle-containing layer in which conductive particles are included in the insulating adhesive composition, and an insulating adhesive layer in which the conductive adhesive particles are not included in the insulating adhesive composition. A laminated anisotropic conductive film having a two-layer structure is described, and it is described that repairability is imparted by adjusting a component of a base resin of the anisotropic conductive film.

Japanese Patent Application No. 7-73922 Japanese Patent Application No. 2004-47228

  Thus, even if it is the anisotropic conductive film which provided the repair property, it is necessary to ensure high connection reliability. However, the repair property and adhesiveness of the anisotropic conductive film are contradictory properties. For this reason, when using the anisotropic conductive film which provided repair property, it was difficult to express sufficient connection reliability.

  In particular, with recent miniaturization and higher performance of electrical devices, the fine pitch of electrodes has been promoted in electronic components and substrates, but good connection reliability is also achieved in the fine pitch connection between electronic components and substrates. It is demanded to obtain high connection reliability while ensuring high reliability. In the case of fine pitch connection, since the connection area is extremely small, it was necessary to increase the number of conductive particles in the anisotropic conductive film in order to ensure good connection reliability.

  However, when the conductive particles are increased, a large number of conductive particles move with the flow of the insulating adhesive composition at the time of thermal pressurization, so that between the adjacent wiring electrodes and between the adjacent terminal electrodes. There was a possibility that the conductive particles aggregated, thereby causing a short circuit. In order to maintain good insulation reliability by suppressing the occurrence of short circuit due to the aggregation of such conductive particles, to suppress the movement of conductive particles during thermal pressurization, in order to ensure excellent conduction reliability Therefore, it was necessary to improve the particle capture rate.

  Therefore, in many fine pitch connections, a conductive particle containing layer in which the movement of the conductive particles is suppressed by fixing the conductive particles in the insulating adhesive composition having a high melt viscosity, and the conductive particles In general, an anisotropic conductive film having a two-layer structure formed by laminating an adhesive layer composed only of an insulating adhesive composition not included is used.

  Usually, in fine pitch connection, from the viewpoint of obtaining a high particle capture rate, an anisotropic conductive film is temporarily attached with the conductive particle-containing layer facing the connection surface of the substrate. However, since the melt viscosity of the conductive particle-containing layer is high, only a small adhesion (tack) force can be obtained with respect to the connection surface of the substrate in the temporary attachment, so that the adhesiveness is lowered. Moreover, the connection reliability in a connection structure will fall.

  The present invention has been proposed in view of such a conventional situation, and exhibits excellent repairability after temporarily sticking an anisotropic conductive film with high adhesive force, and obtains excellent connection reliability. A connecting method in which a substrate and an electronic component are connected by the connecting method, an anisotropic conductive film applied to the connecting method, and a method for manufacturing the anisotropic conductive film are provided. For the purpose.

In order to solve the above-described problems, the connection method of the present invention connects a connection surface on which a wiring electrode of a substrate is formed and a connection surface on which a terminal electrode of an electronic component is formed through an anisotropic conductive film. In the connection method, the anisotropic conductive film has a conductive particle-containing layer in which conductive particles are contained in the first insulating adhesive composition, and a minimum melt viscosity than the first insulating adhesive composition. An insulating adhesive layer containing insulating particles is laminated on a low second insulating adhesive composition, and the insulating particles protrude from the surface of the insulating adhesive layer. The ratio of the length of the insulating particles protruding from the surface of the insulating adhesive layer to the average particle diameter of the insulating particles is 30 to 60%, and the diameter of the insulating particles is displaced by 10%. The compression modulus (10% K value) is 4000 N / mm ² or less The anisotropic conductive film is temporarily pasted on the substrate so that the surface of the insulating adhesive layer from which the insulating particles protrude and the connection surface on which the wiring electrodes of the substrate are formed are opposed to each other. An electronic component is disposed, and the wiring electrode of the substrate and the terminal electrode of the electronic component are anisotropically conductively connected by thermal pressing.

In order to solve the above-described problems, the connection structure according to the present invention includes an anisotropic conductive film in which a connection surface on which a wiring electrode of a substrate is formed and a connection surface on which a terminal electrode of an electronic component is formed. In the connection structure that is connected to each other, the anisotropic conductive film includes a conductive particle-containing layer in which conductive particles are contained in the first insulating adhesive composition, and the first insulating adhesive composition. An insulating adhesive layer containing insulating particles is laminated on the second insulating adhesive composition having a lower minimum melt viscosity than the insulating adhesive layer from the surface of the insulating adhesive layer. The ratio of the length of the insulating particles protruding from the surface of the insulating adhesive layer to the average particle diameter of the insulating particles is 30 to 60%, and the diameter of the insulating particles is 10%. The compressive elastic modulus (10% K value) when% displacement is 4000 N / mm ² or less, an anisotropic conductive film is temporarily attached on the substrate by facing the surface where the insulating particles of the insulating adhesive layer protrude and the connection surface on which the wiring electrode of the substrate is formed. An electronic component is arranged on a conductive film, and is connected by a connection method in which a connection surface on which a wiring electrode of a substrate is formed and a terminal electrode of the electronic component are anisotropically conductively connected by heat and pressure. To do.

In order to solve the above-described problems, the anisotropic conductive film of the present invention includes a conductive particle-containing layer in which conductive particles are contained in the first insulating adhesive composition, and a first insulating adhesive. In an anisotropic conductive film in which an insulating adhesive layer containing insulating particles is laminated on a second insulating adhesive composition having a minimum melt viscosity lower than that of the agent composition, the insulating adhesive layer is The insulating particles protrude from the surface of the insulating adhesive layer, and the ratio of the length of the insulating particles protruding from the surface of the insulating adhesive layer to the average particle diameter of the insulating particles is 30 to 60%. The compression elastic modulus (10% K value) when the diameter of the insulating particles is displaced by 10% is 4000 N / mm ² or less.

In order to solve the above-described problem, the method for producing an anisotropic conductive film of the present invention includes a conductive particle-containing layer in which conductive particles are contained in the first insulating adhesive composition, In a method for producing an anisotropic conductive film, in which an insulating adhesive layer containing insulating particles is laminated on a second insulating adhesive composition having a minimum melt viscosity lower than that of the insulating adhesive composition Then, the first insulating adhesive composition containing conductive particles is applied onto the release film and dried to form a conductive particle-containing layer. On the conductive particle-containing layer, the insulating particles are formed. The first insulating adhesive composition containing sapphire is applied and dried to form an insulating adhesive layer, and the insulating particles are dispersed on the surface of the insulating adhesive layer. The particles protrude from the surface of the insulating adhesive layer, and the average particle size of the insulating particles is The ratio of the length of the insulating particles protruding from the surface of the insulating adhesive layer is 30 to 60%, and the compressive elastic modulus (10% K value) when the diameter of the insulating particles is displaced by 10% is: It is 4000 N / mm < ² > or less.

  ADVANTAGE OF THE INVENTION According to this invention, while exhibiting the outstanding repair property after temporarily sticking an anisotropic conductive film with high adhesive force, the outstanding connection reliability can be obtained.

It is a schematic cross section of the transversal direction (width direction) of the anisotropic conductive film applied to embodiment of this invention. It is a schematic cross section of the structure for demonstrating the connection method applied to embodiment of this invention. It is a schematic cross section of the structure for demonstrating the connection method applied to embodiment of this invention. It is a schematic cross section of the structure for demonstrating the connection method applied to embodiment of this invention. It is a schematic cross section of the transversal direction (width direction) of the anisotropic conductive film applied to other embodiment of this invention.

  Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.

  In an embodiment of the present invention, an LCD (Liquid Crystal Display) panel is configured through an anisotropic conductive film having a two-layer structure including a conductive particle-containing layer containing conductive particles and an insulating adhesive layer. Provided is a connection method in which a glass substrate and an IC (Integrated Circuit) chip which is a kind of electronic component are connected by pressure bonding. Wiring electrodes are formed on the glass substrate at a fine pitch. Further, bumps (terminal electrodes) are formed on the IC chip according to the wiring pattern of the wiring electrodes. And by this connection method, the connection structure is obtained by anisotropically connecting the wiring electrode of the glass substrate and the bump of the IC chip.

  FIG. 1 is a schematic cross-sectional view in the lateral direction (width direction) of an anisotropic conductive film 1 applied to the present embodiment. The anisotropic conductive film 1 is formed by forming a conductive particle-containing layer 12 in which conductive particles 12b are arranged in a single layer on an insulating adhesive composition 12a on a release film (separator) 11 to form conductive particles. An insulating adhesive containing no conductive particles in the insulating adhesive composition 13a having a lower viscosity (minimum melt viscosity) when melted before the start of curing than the insulating adhesive composition 12a on the containing layer 12 The layer 13 is formed into a two-layer structure.

  In the conductive particle-containing layer 12, a large number of conductive particles 12b are firmly fixed by an insulating adhesive composition 12a having a high minimum melt viscosity. Thereby, the fine pitch connection between the wiring electrode and the bump can be easily performed. Moreover, in the insulating adhesive layer 13, the insulating adhesive composition 13a having a low minimum melt viscosity can exhibit a high adhesive force even when the heating temperature is low when the anisotropic conductive film 1 is temporarily attached. Therefore, it can be easily melted by thermocompression at the time of connection, and high connection reliability can be exhibited.

  The insulating adhesive layer 13 includes insulating particles 13b. The insulating particles 13b are embedded in the insulating adhesive layer 13 so that a part of the insulating particles 13b protrudes from the surface of the insulating adhesive layer 13 that is not in contact with the conductive particle-containing layer 12.

Projecting of an average particle diameter of the insulating particles 13b r, the length protruding from the insulating adhesive layer 13 the surface of the insulating particles 13b and r _a, the insulating adhesive layer 13 the surface of the insulating particles 13b The rate t is expressed by _ra / r × 100 (%). The protrusion rate t is preferably 30 to 60%, and more preferably 45 to 55%. When the protrusion rate t is less than 30%, a sufficient gap is not formed between the protruding portion of the insulating particles 13b and the surface of the glass substrate, so that the repairability is deteriorated. On the other hand, if it exceeds 60%, the insulating particles 13b may be detached from the surface of the insulating adhesive layer 13 and fall off.

The hardness of the insulating particles 13b (compression elastic modulus when the diameter of the insulating particles is displaced by 10%: 10% K value) is preferably 4000 N / mm ² or less. Compression modulus (10% K value is 4000 N / mm ² or less, so that the insulating particles 13b can be easily crushed by pressurization.

  Conventionally, in order to temporarily attach a conductive particle-containing layer having a high melt viscosity to a substrate with sufficient adhesive force, it has been necessary to perform thermocompression bonding at a relatively high temperature even when temporarily attaching. It was. Increasing the heating temperature during temporary attachment increases the fluidity of the insulating adhesive composition of the anisotropic conductive film, thereby reducing the filling amount of the insulating adhesive composition between the substrate and the electronic component. Connection reliability is reduced.

  Moreover, when heating temperature is made high at the time of temporary sticking, the hardening reaction of an insulating adhesive composition will start at that time. Therefore, since the cured insulating adhesive composition remains, workability in the repair process is lowered, and the cured adhesive composition cannot be excluded, thereby reducing connection reliability.

  Therefore, in the present embodiment, the anisotropic conductive film 1 is attached with the insulating adhesive layer 13 facing the surface of the glass substrate. Thereby, it can adhere | attach firmly with respect to a glass substrate with the adhesive force of the insulating adhesive layer 13 with the lowest minimum melt viscosity. At the same time, the anisotropic conductive film 1 can be attached in a state where a gap is formed between the protruding portion of the insulating particles 13b and the surface of the glass substrate. It can be easily peeled off from the surface. Thus, the anisotropic conductive film 1 can exhibit excellent repair properties while ensuring high adhesion by the insulating adhesive layer 13 from which the insulating particles 13b are projected.

  In this Embodiment, a glass substrate and an electronic component are connected through the anisotropic conductive film 1 of such a two-layer laminated structure. Specifically, as shown in FIG. 2, the surface of the insulating adhesive layer 13 from which the insulating particles 13b protrude is brought into contact with the glass substrate 14 on the surface of the glass substrate 14 on which the wiring electrodes 15 are formed. Thus, the anisotropic conductive film 1 is temporarily pasted (temporary pasting step). Then, the alignment state of the anisotropic conductive film 1 is confirmed, and when there is a problem such as misalignment, the anisotropic conductive film 1 is peeled off and the anisotropic conductive film 1 is placed again in the correct position. Repair processing for temporary attachment is performed (repair process). Next, as shown in FIG. 3, the IC chip 16 is disposed on the conductive particle-containing layer 12 of the anisotropic conductive film 1 (arrangement step). Then, as shown in FIG. 4, the glass substrate 14 and the IC chip 16 are crimped and connected by heat and pressure to obtain a connection structure (connection process). Details of this connection method will be described later.

  The melting point of the insulating particles 13b is set to be higher than the heating temperature for thermal pressurization at a low temperature and in a short time in the temporary pasting process, and can be set lower than the heating temperature for thermal pressurization in the connection process. Thereby, in the temporary sticking process, while maintaining the shape of the insulating particle 13b, it can stick, and in a connection process, it can melt | dissolve easily and can be connected with high adhesive force. Such a melting point can be 105 to 165 ° C.

  The insulating adhesive composition 12a of the conductive particle-containing layer 12 preferably has a minimum melt viscosity adjusted to 10 times or more the minimum melt viscosity of the insulating adhesive composition 13a of the insulating adhesive layer 13. . The minimum melt viscosity of the insulating adhesive composition 12a of the conductive particle-containing layer 12 is preferably 10000 to 16000 Pa · s. If it is less than 10,000 Pa · s, a large number of conductive particles 13b cannot be fixed. On the other hand, if it exceeds 16000 Pa · s, it cannot be easily melted even in the heat and pressure in the connecting step. The minimum melt viscosity of the insulating adhesive composition 13a of the insulating adhesive layer 13 is preferably 700 to 1100 Pa · s. When the pressure is less than 700 Pa · s, the glass substrate 14 is firmly bonded even in the thermocompression bonding in the temporary bonding step, and the repair process becomes impossible. On the other hand, when it exceeds 1100 Pa · s, it is not possible to exhibit an excellent adhesion force (tack force) to the glass substrate 14 in the temporary sticking step.

  By adjusting the minimum melt viscosity of the conductive particle-containing layer 12 and the insulating adhesive layer 13 in this manner, the insulating adhesive layer 13 having a low minimum melt viscosity causes an adhesive force in the temporary application step. Sufficient adhesion to the glass substrate 14 can be ensured. At the same time, by attaching the insulating adhesive layer 13 to the glass substrate 14 with a gap between the protruding portion of the insulating particles 13b and the glass substrate 14, an anisotropic conductive film is used in the repair process. 1 can be easily peeled from the glass substrate 14. Thus, the anisotropic conductive film 1 can exhibit excellent repair properties while ensuring high adhesion by the insulating adhesive layer 13 from which the insulating particles 13b are projected.

  In the connecting step, when thermal pressing is started, the insulating adhesive composition 13a of the insulating adhesive layer 13 having the lowest minimum melt viscosity is melted to cause the glass substrate 14 to be adhesive. Further, in the connection step, the insulating particles 13b between the bumps 17 and the wiring electrodes 15 are crushed by the bumps 17 by pressurization, and are easily melted by heating, so that the particle shape rapidly collapses. The conductive particles 13b are firmly held and fixed between the bumps 17 and the wiring electrodes 15. Thereby, a high particle capture rate can be obtained. Thus, in the connection structure, excellent connection reliability and conduction reliability can be exhibited.

  In the conductive particle-containing layer 12, the conductive particles 12b are arranged and fixed, for example, in a single layer. Thereby, a movement of the electroconductive particle 12b can be suppressed in a temporary sticking process. In the connecting step, the insulating particles 13b between the adjacent wiring electrodes 15 are melted but are not crushed by the bumps 17, so that the insulating particles 13b between the bumps 17 and the wiring electrodes 15 are melted. Then, the particle shape is still maintained. Thus, the conductive particles 12b arranged in a single layer in the conductive particle-containing layer 12 are present on the insulating particles 13b or in the gaps between the insulating particles 13b by the heat and pressure in the connection step. Move distributed. In this way, in the connection step, the occurrence of a short circuit due to the aggregation of the conductive particles 12b is suppressed, and the insulation reliability can be maintained well. In the conductive particle-containing layer 12, the conductive particles 12b are not limited to being arranged in a single layer, and may be arranged randomly, for example, as shown in another embodiment of FIG. Conductive particle-containing layer 12 ′).

  The insulating particles 13b are resin particles having crystallinity. The average particle diameter of the insulating particles 13b is preferably 3.0 μm to 8.0 μm, and more preferably 4.0 μm to 7.0 μm. The melting point of the insulating particles 13b is preferably set higher than the heating temperature in the temporary sticking step and lower than the heating temperature in the connecting step, and can be set to, for example, 100 to 170 ° C.

  Examples of the material constituting the insulating particles 13b include polyethylene, nylon, silicone, special ethylene copolymer (EMMA), and polyurethane.

  The insulating adhesive composition 12a of the conductive particle-containing layer 12 is composed of a binder component containing a film-forming resin, a polymerizable acrylic compound, and an organic peroxide.

  As the film forming resin, for example, a thermoplastic elastomer such as an epoxy resin, a polyester resin, a polyurethane resin, a phenoxy resin, polyamide, EVA, or the like can be used. Among them, for heat resistance and adhesiveness, polyester resins, polyurethane resins, phenoxy resins, particularly phenoxy resins such as bis A type epoxy resins and phenoxy resins having a fluorene skeleton can be mentioned.

  If the amount of the film-forming resin is too small, a film is not formed. If the amount is too large, the resin exclusion property for obtaining electrical connection tends to be low, so that the resin solid content (the polymerizable acrylic compound and the film-forming resin The total is 30 to 80 parts by mass, more preferably 40 to 70 parts by mass with respect to 100 parts by mass.

  Examples of the polymerizable acrylic compound include polyethylene glycol diacrylate, phosphate ester acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, isobutyl acrylate, t-butyl acrylate, and isooctyl acrylate. Bisphenoxyethanol full orange acrylate, 2-acryloyloxyethyl succinic acid, lauryl acrylate, stearyl acrylate, isobornyl acrylate, tricyclodecane dimethanol dimethacrylate, cyclohexyl acrylate, tris (2-hydroxyethyl) isocyanurate triacrylate, Tetrahydrofurfuryl acrylate, o-phthalic acid diglycidyl ether acrylate, Carboxymethyl bisphenol A dimethacrylate, bisphenol A type epoxy acrylate, urethane acrylate, epoxy acrylate, and can be given the corresponding (meth) acrylate thereto.

  The polymerizable acrylic compound has 5 to 40 parts by weight of a bifunctional acrylate, 10 to 40 parts by weight of a urethane acrylate, and 0.5 to 5 parts by weight of a phosphoric ester acrylate in terms of obtaining high adhesive strength and conduction reliability. It is preferable to use the part together. Here, the bifunctional acrylate is blended to improve the cohesive strength of the cured product and improve the conduction reliability, the urethane acrylate is blended to improve the adhesion to the polyimide, and the phosphate ester acrylate is blended to the metal. Formulated to improve adhesion.

  If the amount of the polymerizable acrylic compound used is too small, the conduction reliability tends to be low, and if it is too large, the adhesive strength tends to be low. Therefore, it is preferable that the resin solid content (polymerizable acrylic compound and film-forming resin be The total is 20 to 70 parts by mass, more preferably 30 to 60 parts by mass with respect to 100 parts by mass.

  Examples of the organic peroxide include di (4-methylbenzoyl) peroxide (1 minute half-life temperature 128.2 ° C), di (3-methylbenzoyl) peroxide (1 minute half-life temperature 131.1 ° C). Dibenzoyl peroxide (1 minute half-life temperature 130.0 ° C.), t-hexyl peroxybenzoate (1 minute half-life temperature 160.3 ° C.), t-butyl peroxybenzoate (1 minute half-life temperature 166.8 ° C.) ), Diisobutyryl peroxide (1 minute half-life temperature 85.1 ° C.), 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate (1 minute half-life temperature 124.3 ° C.), dilauroyl per Oxide (1 minute half-life temperature 116.4 ° C), di (3,5,5-trimethylhexanoyl) peroxide (1 minute Deterioration temperature 112.6 ° C), t-butyl peroxypivalate (1 minute half-life temperature 110.3 ° C), t-hexyl peroxypivalate (1 minute half-life temperature 109.1 ° C), t-butyl Peroxyneoheptanoate (1 minute half-life temperature 104.6 ° C), t-butyl peroxyneodecanoate (1 minute half-life temperature 103.5 ° C), t-hexyl peroxyneodecanoate (1 Min half-life temperature 100.9 ° C), di (2-ethylhexyl) peroxydicarbonate (1 min half-life temperature 90.6 ° C), di (4-t-butylcyclohexyl) peroxydicarbonate (1 min half-life) Temperature 92.1 ° C), 1,1,3,3-tetramethylbutyl peroxyneodecanoate (1 minute half-life temperature 92.1 ° C), di-sec-butyl pero Sidicarbonate (1 minute half-life temperature 85.1 ° C), di-n-propyl peroxydicarbonate (1 minute half-life temperature 85.1 ° C), cumyl peroxyneodecanoate (1 minute half-life temperature 85. 1 ° C). Two or more of these can be used in combination.

  When the amount of the organic peroxide is too small, the reactivity is lost, and when the amount is too large, the cohesive force of the anisotropic conductive film tends to decrease. Therefore, the amount is preferably 1 to 10 mass with respect to 100 parts by mass of the polymerizable acrylic compound. Part, more preferably 3 to 7 parts by mass.

  As the conductive particles 12b of the conductive particle-containing layer 12, conductive particles used in conventional anisotropic conductive films can be used. For example, metal particles such as gold particles, silver particles, and nickel particles Examples thereof include metal-coated resin particles in which the surfaces of resin particles such as benzoguanamine resin and styrene resin are coated with a metal such as gold, nickel, and zinc. The average particle diameter of the conductive particles 12b is preferably 1 to 20 μm, more preferably 2 to 10 μm, from the viewpoint of connection reliability.

In the conductive particle-containing layer 12, the average particle density of the conductive particles 12b is preferably 500 to 50000 particles / mm ² , more preferably 1000 to 30000 particles / mm ² from the viewpoint of connection reliability and insulation reliability. is there.

  In addition, the conductive particle-containing layer 12 includes other additive compositions such as dilution monomers such as various acrylic monomers, fillers, softeners, colorants, flame retardants, thixotropic agents, silane coupling agents, Silica fine particles and the like can be contained.

  By including the silane coupling agent, the adhesion at the interface between the organic material and the inorganic material is improved. By including silica fine particles, the storage elastic modulus, the linear expansion coefficient, etc. can be adjusted to improve the connection reliability.

  The insulating adhesive composition 13a of the insulating adhesive layer 13 is composed of a binder component containing a film-forming resin, a polymerizable acrylic compound, and an organic peroxide, and has an insulating property of the conductive particle-containing layer 12. It consists of the same components as the adhesive composition 12a.

  The insulating adhesive compositions 12 a and 13 a are adjusted so that the minimum melt viscosity of the conductive particle-containing layer 12 is 10 times or more the minimum melt viscosity of the insulating adhesive layer 13.

  As the release film 11, for example, a release agent such as silicone is applied to PET (Poly Ethylene Terephthalate), OPP (Oriented Polypropylene), PMP (Poly-4-methlpentene-1), PTFE (Polytetrafluoroethylene), etc. While preventing the anisotropic conductive film 1 from drying, the shape of the anisotropic conductive film 1 is maintained.

  Although the anisotropic conductive film 1 may be produced by any method, for example, it can be produced by the following method.

  An insulating adhesive composition 12a containing a film-forming resin, a polymerizable acrylic compound, and an organic peroxide is prepared. The insulating adhesive composition 12a is applied onto the release film 11 by a bar coater. Conductive particles 12b are arranged in a single layer at a predetermined position near the surface of the coated material. The coating material in which the conductive particles 12b are arranged in a single layer is dried by heating in an oven to obtain the conductive particle-containing layer 12.

  Here, as a method of arranging the conductive particles 12b in a single layer in the conductive particle-containing layer 12, for example, the following method can be exemplified. That is, a method of arranging the conductive particles 12b in a single layer on the insulating adhesive composition 12a formed on the release film 11 by a spray method, or using a squeegee or the like on the insulating adhesive composition 12a. A method of arranging the particles 12b in a single layer can be appropriately used. Further, for example, the conductive particles 12b arranged in a single layer on the insulating adhesive composition 12a may be pushed into the insulating adhesive composition 12a using a laminator.

  When the conductive particle-containing layer 12 ′ in which the conductive particles 12b are randomly dispersed is used in place of the conductive particle-containing layer 12, the conductive particles 12b are dispersed in the insulating adhesive composition 12a. Let The conductive particle containing composition obtained by this is apply | coated on the peeling film 11 with a bar coater. Then, the coated material can be dried by heating in an oven to obtain the conductive particle-containing layer 12 '.

  Next, an insulating adhesive composition 13a containing a film-forming resin, a polymerizable acrylic compound, and an organic peroxide is prepared. Insulating adhesive composition 13a is applied onto conductive particle-containing layer 12 by a bar coater. The layer made of the insulating coating is dried by heating in an oven to obtain the insulating adhesive layer 13 on the conductive particle-containing layer 12.

  By dispersing the insulating particles 13b in a dispersion medium such as toluene, hexane, isopropyl alcohol (IPA), a slurry solution of the insulating particles 13b is prepared. By spraying the slurry solution of the insulating particles 13b on the surface of the insulating adhesive layer 13 with a sprayer, the insulating particles 13b are dispersed on the surface of the insulating adhesive layer 13. Thereafter, a two-layer film laminate in which the insulating adhesive layer 13 is laminated on the conductive particle-containing layer 12 is laminated by a laminator. Thereby, the insulating particles 13 b are embedded in the insulating adhesive layer 13 so that only the tops of the insulating particles 13 b protrude from the insulating adhesive layer 13. The anisotropic conductive film 1 can be produced by the above treatment.

  Next, a method for manufacturing a connection structure, a connection structure, and a connection method according to the present embodiment will be described in detail. First, as shown in FIG. 2, the anisotropic conductive film is formed by confronting the surface on which the wiring electrode 15 on the glass substrate 14 is formed with the surface from which the insulating particles 13b of the insulating adhesive layer 13 protrude. 1 is temporarily pasted on the glass substrate 14 (temporary pasting step). In this temporary attachment, the pressure surface (not shown) of the head portion heated to a low temperature of the pressure bonder is lightly pressed against the upper surface of the conductive particle-containing layer 12 and pressed at a low pressure. The heating temperature is a low temperature (for example, a predetermined value of 60 to 80 ° C.) such that the insulating particles 13b do not dissolve and the insulating adhesive compositions 12a and 13a flow but do not cure. Moreover, the pressurization pressure in a temporary sticking process is a predetermined value in 0.5 MPa-2 MPa, for example. Moreover, the heat pressurization time in a temporary sticking process is predetermined time in 1-3 seconds (sec), for example.

  After temporarily sticking the anisotropic conductive film 1 in the temporary sticking step, the alignment state of the anisotropic conductive film 1 is confirmed, and if a problem such as misalignment occurs, after this temporary sticking step, The anisotropic conductive film 1 is peeled off, and a repair process for temporarily attaching the anisotropic conductive film 1 at the correct position is performed again (repair process).

  In the temporary sticking step, the anisotropic conductive film 1 temporarily attached to the glass substrate 14 has the insulating particles 13 b protruding from the surface of the insulating adhesive layer 13. As a result, the protruding portion adheres to the glass substrate 14 in a state where a gap is formed between the protruding portion of the insulating particles 13 b and the glass substrate 14. For this reason, in a repair process, the anisotropic conductive film 1 can be easily peeled from the glass substrate 14, and high repair property can be exhibited.

  Next, as shown in FIG. 3, the IC chip 16 is disposed on the conductive particle-containing layer 12 of the anisotropic conductive film 1 so that the bumps 17 and the wiring electrodes 15 face each other (arrangement step).

  Then, the pressure surface (not shown) of the heated head part of the pressure bonder is pressed against the upper surface of the IC chip 16, and the glass substrate 14 and the IC chip 16 are pressure-bonded as shown in FIG. 4 (connection process). ).

  The pressurizing pressure in the connecting step is, for example, a predetermined value from 1.0 MPa to 5.0 MPa. The heating temperature in the connecting step is a temperature (for example, a predetermined value of 170 to 190 ° C.) that melts the insulating particles 13b and cures the insulating adhesive compositions 12a and 13a. Moreover, the heat pressurizing time in the connecting step is, for example, a predetermined time of 3 to 20 seconds.

  In this way, the conductive particles 12b are sandwiched between the wiring electrodes 15 and the bumps 17, and the insulating adhesive compositions 12a and 13a are cured. Thereby, the glass substrate 14 and the IC chip 16 are electrically and mechanically connected. Then, a connection structure in which the glass substrate 14 and the IC chip 16 are anisotropically conductively connected is obtained. As described above, the obtained connection structure can exhibit excellent connection reliability and conduction reliability while maintaining good insulation reliability.

  As mentioned above, although this Embodiment was described, it cannot be overemphasized that this invention is not limited to the above-mentioned embodiment, A various change is possible in the range which does not deviate from the summary of this invention.

  Moreover, although the above-mentioned embodiment demonstrated the case where the glass substrate 1 which comprises a LCD (Liquid Crystal Display) panel was used as a glass substrate, a glass substrate is not limited to this, For example, a PDP board | substrate (PDP) Panel), an organic EL substrate (organic EL panel) and the like.

  In the above-described embodiment, the case where a glass substrate is used as the substrate has been described. However, other substrates such as a rigid substrate and a flexible substrate may be used. In the above-described embodiment, the case where an IC chip is used as an electronic component has been described. However, other electronic components such as COF and TAB may be used.

  In the above-described embodiment, the case where the present invention is applied to COG (Chip On Glass) has been described. However, the present invention is not limited to other mounting methods such as FOG (Film On Glass) and FOB (Film On Board). It can also be applied to.

  Hereinafter, specific examples of the present invention will be described based on experimental results.

<Example 1>
Phenoxy resin (YP-50, manufactured by Nippon Steel Chemical Co., Ltd.) 50 parts by mass, bifunctional acrylate monomer (DCP, manufactured by Shin Nakamura Chemical Co., Ltd.) 12 parts by mass, monofunctional acrylate monomer (A-SA, Shin Nakamura Chemical) Industrial Co., Ltd.) 5 parts by mass, urethane acrylate (U-2PPA, Shin-Nakamura Chemical Co., Ltd.) 15 parts by mass, silica fine particles (Aerosil RY200, Nippon Aerosil Co., Ltd.) 10 parts by mass, phosphate ester acrylate ( PM-2, manufactured by Nippon Kayaku Co., Ltd.) 3 parts by mass, silane coupling agent (KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.) 1 part by mass, and organic peroxide (Perocta O, manufactured by NOF Corporation) 4 Toluene was added to mass parts so that the solid concentration was 50% to prepare a resin composition. This resin composition was applied onto a PET film as a release film by a bar coater. In the coated material, 4.0 parts by mass of an average particle diameter of 3 μm, a resin core, and Ni / Au plated conductive particles (AUL703, manufactured by Sekisui Chemical Co., Ltd.) were arranged in a single layer. In addition, the electroconductive particle was arranged in the single layer according to the spraying method of Example 1 of Unexamined-Japanese-Patent No. 2009-134914. The coated material on which the conductive particles were arranged was dried by heating in an oven to obtain a conductive particle-containing layer having a thickness of 5 μm. The conductive particle-containing layer had an average particle density of 15,000 particles / mm ² and a minimum melt viscosity of 13000 Pa · s.

  25 parts by mass of phenoxy resin (YP-50, manufactured by Nippon Steel Chemical Co., Ltd.), 30 parts by mass of phenoxy resin (jER4004, Mitsubishi Chemical Corporation), 12 parts by mass of bifunctional acrylate monomer (DCP, manufactured by Shin-Nakamura Chemical Co., Ltd.) Parts, monofunctional acrylate monomer (A-SA, Shin-Nakamura Chemical Co., Ltd.) 5 parts by mass, urethane acrylate (U-2PPA, Shin-Nakamura Chemical Co., Ltd.) 20 parts by mass, phosphate ester acrylate (PM- 2, Nippon Kayaku Co., Ltd.) 3 parts by mass, Silane coupling agent (KBM-503, Shin-Etsu Chemical Co., Ltd.) 1 part by mass, and organic peroxide (Perocta O, manufactured by NOF Corporation) 4 parts by mass In addition, a resin composition was prepared by adding toluene so that the solid concentration was 50%. This resin composition was applied onto the conductive particle-containing layer by a bar coater and dried by heating in an oven to obtain an insulating adhesive layer having a thickness of 9 μm and a minimum melt viscosity of 800 Pa · s.

Insulating particles made of polyethylene having an average particle size of 6.0 μm, hardness (compression modulus: 10% K value) 1500 N / mm ² and melting point 105 ° C. (low density polyethylene particles LE-1080, manufactured by Sumitomo Seika Co., Ltd.) Was dispersed in a dispersion medium (isopropyl alcohol) to prepare a slurry liquid of insulating particles. The insulating particles were sprayed on the surface of the insulating adhesive layer by spraying the slurry of insulating particles on the surface of the insulating adhesive layer with a sprayer.

Thereafter, the two-layer film laminate was laminated with a laminator, and the insulating particles were embedded in the insulating adhesive layer so that only the top of the insulating particles protruded from the insulating adhesive layer (Arrangement A). . An anisotropic conductive film was produced by such treatment. Protrusion rate t (r _a / r × 100 (%)) which is _a ratio of length ra protruding from the surface of the insulating adhesive layer of the insulating particles to the average particle diameter r (= 6.0 μm) of the insulating particles ) Was 50%.

  Next, the process which connects a glass substrate and an IC chip through the produced anisotropic conductive film was performed. First, the anisotropic conductive film was temporarily pasted on the glass substrate by facing the surface on which the wiring electrodes on the glass substrate were formed and the surface from which the insulating particles of the insulating adhesive layer protruded (temporary pasting). Process). In this temporary attachment, the pressure surface of the head part heated to a low temperature of the pressure bonder was lightly pressed against the upper surface of the conductive particle-containing layer and pressed at a low pressure. The heating temperature was set to 70 ° C., which is a low temperature at which the insulating particles do not dissolve and the insulating adhesive composition flows but does not cure. Moreover, the pressurization pressure in the temporary sticking process was 1 MPa. Moreover, the heat-pressing time in the temporary sticking process was 2 seconds.

  After the temporary sticking step, the anisotropic conductive film was peeled off and the anisotropic conductive film was repaired again by temporary sticking at the correct position (repair step).

  Next, the IC chip was placed on the conductive particle-containing layer of the anisotropic conductive film so that the bump of the IC chip and the wiring electrode of the glass substrate were opposed to each other (placement step).

  Then, the pressure surface of the heated head part of the pressure bonder was pressed against the upper surface of the IC chip, and the glass substrate and the IC chip were connected by pressure bonding (connection process).

  The pressurizing pressure in the connecting step was 1 MPa. The heating temperature in the connection process was 190 ° C. Further, the heat pressurizing time in the connecting step was 10 seconds.

  In this way, conductive particles are sandwiched between the wiring electrodes and the bumps, the insulating adhesive composition is cured, and the glass substrate and the IC chip are electrically and mechanically connected. Obtained.

<Example 2>
Instead of the insulating particles of Example 1, nylon insulating particles (SP-500, Toray) having an average particle size of 5.9 μm, hardness (compression modulus: 10% K value) 2000 N / mm ² , melting point 165 ° C. Used). Otherwise, the connection process was performed in the same manner as in Example 1.

<Reference Example 1>
Instead of the insulating particles of Example 1, polyethylene insulating particles (low-density polyethylene particles LE) having an average particle diameter of 2.0 μm, hardness (compression modulus: 10% K value) 1500 N / mm ² , and melting point 105 ° C. -1080, manufactured by Sumitomo Seika Co., Ltd.). Otherwise, the connection process was performed in the same manner as in Example 1.

<Reference Example 2>
Instead of the insulating particles of Example 1, polyethylene insulating particles (low-density polyethylene particles LE) having an average particle diameter of 10.0 μm, hardness (compression modulus: 10% K value) 1500 N / mm ² , melting point 105 ° C. -1080, manufactured by Sumitomo Seika Co., Ltd.). Otherwise, the connection process was performed in the same manner as in Example 1.

<Example 3>
Instead of the conductive particle-containing layer of Example 1, conductive particles were dispersed in the resin composition, and conductive particles were randomly arranged (thickness 6 μm, conductive particle density 20000 / mm ² and a minimum melt viscosity of 13,000 Pa · s). Further, instead of the insulating particles of Example 1, silicone resin particles having an average particle size of 4.5 μm and hardness (compression modulus: 10% K value) of 2500 N / mm ² (Tospearl 145, Momentive Performance Materials Japan GK) Made).

  Instead of the amount of the phenoxy resin in the insulating adhesive layer of Example 1, 30 parts by mass of phenoxy resin (YP-50, manufactured by Tohto Kasei Co., Ltd.) and 25 parts by mass of phenoxy resin (jER4004, Mitsubishi Chemical Corporation) were used. . An insulating adhesive layer having a thickness of 10 μm and a minimum melt viscosity of 1000 Pa · s was obtained. And the pressurization pressure in the connection process was 3 MPa. The heating temperature in the connecting step was 170 ° C. Further, the heat pressurizing time in the connecting step was 5 seconds. Otherwise, the connection process was performed in the same manner as in Example 1.

<Example 4>
Instead of the insulating particles of Example 3, EMMA resin particles (soft beads A, average particle size 10.0 μm, manufactured by Sumitomo Seika Co., Ltd.) are vibrated with a wet sieve shaker (manufactured by Tsutsui Riken Kikai Co., Ltd.). And particles having an average particle size of 6.2 μm, hardness (compression modulus: 10% K value) of 400 N / mm ² , and a melting point of 100 ° C. Insulating particles were embedded in the insulating adhesive layer by spraying with a sprayer in the state of a slurry liquid prepared by dispersing the particles in a dispersion medium (isopropyl alcohol). Otherwise, the connection process was performed in the same manner as in Example 3.

<Example 5>
Instead of the silicone resin particles of Example 3, PMMA resin particles having a hardness (compression modulus: 10% K value) of 4000 N / mm ² and an average particle size of 6.4 μm (Microsphere-M-100, Matsumoto Yushi Pharmaceutical Co., Ltd.) The connection process was performed in the same manner as in Example 3 except that the company-made product was used.

<Example 6>
The connection treatment was performed in the same manner as in Example 1 except that the insulating particles were protruded from the surface of the insulating adhesive layer at a protrusion rate t = 60%.

<Example 7>
The connection treatment was performed in the same manner as in Example 1 except that the insulating particles were protruded from the surface of the insulating adhesive layer at a protrusion rate t = 30%.

<Comparative Example 1>
An insulating adhesive layer was produced without embedding insulating particles in the insulating adhesive layer. And the anisotropic conductive film of the 2 layer laminated structure by which an insulating adhesive bond layer and an electroconductive particle content layer were laminated | stacked in this order on the peeling film was produced. And the surface in which the wiring electrode on the glass substrate was formed, and the electroconductive particle content layer were made to oppose, and the anisotropic conductive film was temporarily stuck on the glass substrate. Otherwise, the connection process was performed in the same manner as in Example 1.

<Comparative example 2>
An insulating adhesive layer was produced without embedding insulating particles in the insulating adhesive layer. And the anisotropic conductive film of the 2 layer laminated structure by which an electroconductive particle content layer and an insulating adhesive layer were laminated | stacked in this order on the peeling film was produced. And the surface in which the wiring electrode on the glass substrate was formed, and the insulating adhesive layer were made to oppose, and the anisotropic conductive film was temporarily stuck on the glass substrate. Otherwise, the connection process was performed in the same manner as in Example 1.

<Comparative Example 3>
An anisotropic conductive film was temporarily pasted on the glass substrate with the surface on which the wiring electrode on the glass substrate was formed facing the conductive particle-containing layer. Otherwise, the connection process was performed in the same manner as in Example 1.

<Comparative example 4>
The connection treatment was performed in the same manner as in Example 1 except that the insulating particles were protruded from the surface of the insulating adhesive layer at a protrusion rate t = 20%.

<Comparative Example 5>
Insulating particles were embedded in a random state in the insulating adhesive layer. As a result, the insulating particles were completely embedded in the insulating adhesive layer. That is, the insulating particles were not projected from the layer surface (Arrangement B). Otherwise, the connection process was performed in the same manner as in Example 1.

<Comparative Example 6>
By the membrane emulsification method, 1,6-hexanediol diacrylate (A-HD-N, manufactured by Shin-Nakamura Chemical Co., Ltd.), which is a hydrophobic monomer, and urethane acrylate (AH600, manufactured by Kyoeisha Chemical Co., Ltd.), which is a hydrophobic monomer. ) And laurolyl peroxide (Perroyl L, manufactured by NOF Corporation), which is a polymerization initiator, are emulsion-polymerized, and the hardness (compression modulus: 10% K value) is 6400 N / mm ² and the average particle size is 6.2 μm. Acrylic resin particles were prepared. Insulating particles were embedded in the insulating adhesive layer by spraying with a sprayer in the state of a slurry liquid prepared by dispersing the acrylic resin particles in a dispersion medium (isopropyl alcohol). By this spraying, the insulating particles were arranged such that the tops protruded (exposed) from the surface of the insulating adhesive layer (Arrangement A). Otherwise, the connection process was performed in the same manner as in Example 1.

<Comparative Example 7>
Instead of the insulating particles of Example 1, benzoguanamine-based resin particles having an average particle diameter of 6.0 μm and hardness (compression elastic modulus: 10% K value) of 7000 N / mm ² (Epaster GPH60, Nippon Shokubai Co., Ltd.) Company). Otherwise, the connection process was performed in the same manner as in Example 1.

<Comparative Example 8>
An insulating adhesive layer was produced without embedding insulating particles in the insulating adhesive layer. And the anisotropic conductive film of the 2 layer laminated structure by which an insulating adhesive bond layer and an electroconductive particle content layer were laminated | stacked in this order on the peeling film was produced. And the surface in which the wiring electrode on the glass substrate was formed, and the electroconductive particle content layer were made to oppose, and the anisotropic conductive film was temporarily stuck on the glass substrate. Otherwise, the connection process was performed in the same manner as in Example 3.

<Comparative Example 9>
An insulating adhesive layer was produced without embedding insulating particles in the insulating adhesive layer. And the anisotropic conductive film of the 2 layer laminated structure by which an electroconductive particle content layer and an insulating adhesive layer were laminated | stacked in this order on the peeling film was produced. And the surface in which the wiring electrode on the glass substrate was formed, and the insulating adhesive layer were made to oppose, and the anisotropic conductive film was temporarily stuck on the glass substrate. Otherwise, the connection process was performed in the same manner as in Example 3.

<Comparative Example 10>
Hydrophobic monomer 1,6-hexanediol diacrylate A-HD-N (made by Shin-Nakamura Chemical Co., Ltd.) and hydrophobic monomer urethane acrylate (AH600, made by Kyoeisha Chemical Co., Ltd.) And emulsion polymerization of laurolyl peroxide (Perroyl L, manufactured by NOF Corporation) as a polymerization initiator, and a compression modulus: 10% K value 6400 N / mm ² , acrylic resin particles having an average particle size of 6.2 μm Was made. Insulating particles were embedded in the insulating adhesive layer by spraying with a sprayer in the state of a slurry solution prepared by dispersing the acrylic resin particles in a solvent. By this spraying, the insulating particles were arranged such that the tops protruded (exposed) from the surface of the insulating adhesive layer (Arrangement A). Otherwise, the connection process was performed in the same manner as in Example 3.

[Temporary crimping force measurement]
In Examples 1 to 7, Comparative Examples 1 to 10, and Reference Examples 1 and 2, after the anisotropic conductive film was temporarily attached to the glass substrate, the anisotropic conductive film was peeled in the 90 ° C. direction at a tensile strength of 5 cm / min. The peel strength (mN / cm) was measured using a peel strength tester (Tensilon, manufactured by Orientec Co., Ltd.) as a temporary pressure-bonding force (adhesive strength to the glass substrate).

[Repairability evaluation]
The anisotropic conductive film after temporary attachment was peeled off. In this repair work, the temporarily attached anisotropic conductive film was mechanically peeled in the direction of 90 degrees at room temperature (25 ° C.) using a tensile tester (Tensilon, manufactured by Orientec Co., Ltd.). The ratio (%) of the residual area of the anisotropic conductive film on the glass substrate after peeling with respect to the temporary attachment area of the anisotropic conductive film on the glass substrate was measured. The repair property was evaluated by assuming that the residual area ratio of the anisotropic conductive film was less than 10%, and that 10% or more was x.

[Temporary sticking evaluation]
As a comprehensive evaluation at the time of temporary application of the anisotropic conductive film, the temporary application state of the anisotropic conductive film that has a high temporary pressure-bonding force (adhesive force) and can be repaired well is good (○) Then, an anisotropic conductive film applied to at least one of the low temporary pressure bonding force and the poor repairability (x) was evaluated as a poor temporary bonding state (x).

[Evaluation of conduction resistance]
For the connection structures prepared in Examples 1 to 7, Comparative Examples 1 to 10, and Reference Examples 1 and 2, an initial resistance, a temperature test of 60 ° C., a humidity of 95% RH, and a TH test (Thermal Humidity) for 250 hours The resistance after Test) was measured. The measurement was performed using a digital multimeter (digital multimeter 7561, manufactured by Yokogawa Electric Corporation) to measure the connection resistance when a current of 1 mA was passed by the four-terminal method. Evaluation was made with ○ for a conduction resistance value of less than 2.0Ω, Δ for a connection resistance of 2.0Ω to less than 2.5Ω and × for a connection resistance of 2.5Ω or more.

[Evaluation of particle trapping rate]
For each connection structure of Examples 1 to 7, Comparative Examples 1 to 10, and Reference Examples 1 and 2, the number of conductive particles (number of particles before connection) on the wiring electrode of the glass substrate before connection is expressed by the following formula: Calculated according to (1).
Number of particles before connection = particle (surface) density of conductive particles (number / mm ² ) × area of terminal (mm ² ) in the conductive particle-containing layer (1)

Further, the number of conductive particles on the wiring electrode after connection (number of particles after connection) was measured by counting with a metal microscope. And the particle | grain capture | acquisition rate of electroconductive particle was computed by following Formula (2).
Particle capture rate = (number of particles after connection / number of particles before connection) × 100 (2)

  Table 1 summarizes the conditions of Examples 1 to 7, Comparative Examples 1 to 10, Reference Examples 1 and 2, and the results of each evaluation test.

In Examples 1-7, in the temporary sticking step, the insulating adhesive layer containing insulating particles was disposed on the glass substrate side, and the anisotropic conductive film was temporarily attached. In Examples 1 to 5, in the insulating adhesive layer, the protruding rate t of the insulating particles is 50%, in Example 6, the protruding rate t is 60%, and in Example 7, the protruding rate t is 30%. did. Thereby, in Examples 1-7, while being able to acquire adhesive force with respect to a glass substrate, since a clearance gap is made between the protrusion part of insulating particle | grains and a glass substrate, high adhesive force is obtained and repair property is also obtained. It is thought that it was good. Moreover, in the connection process of Examples 1-7, since the 10% K value of the insulating particles is 4000 N / mm ² or less, the insulating particles are formed between the bumps and the wiring electrodes by thermal pressing. It is thought that excellent connection reliability was able to be exhibited because it was crushed and eliminated smoothly.

  In Reference Example 1, since the average particle size of the insulating particles was too small, the repairability deteriorated. Further, in Reference Example 2, since the average particle size of the insulating particles is too large, even in the thermocompression bonding in the connection process, the bumps and the wiring electrodes are not easily crushed and excluded, so the connection reliability is good. It is thought that it was not.

  On the other hand, in Comparative Examples 1, 3, and 8, the conductive particle-containing layer was disposed on the glass substrate side, and an anisotropic conductive film was temporarily attached. Since the conductive particle-containing layer has a high viscosity and thus has low adhesion to the glass substrate, the repair property and the connection reliability were good, but the temporary pressure bonding force (adhesive force) was small.

  In Comparative Examples 2 and 9, an anisotropic conductive film was temporarily attached by disposing an insulating adhesive layer containing no insulating particles on the glass substrate side. Therefore, although the temporary pressure bonding force was high, the repairability deteriorated.

  In Comparative Example 4, the protruding rate t of the insulating particles in the insulating adhesive layer was low, and in Comparative Example 5, the insulating particles were not protruded, so that the repairability was not good in all cases.

  In Comparative Examples 6, 7, and 10, since the compressive elastic modulus (10% K value) of the insulating particles is too high, the insulating particles are sufficient between the bump and the wiring electrode even by the thermal pressurization in the connection process. It is thought that the connection reliability was poor because the connection reliability was not eliminated.

  DESCRIPTION OF SYMBOLS 1 Anisotropic conductive film, 11 Release film, 12 Conductive particle content layer, 12a, 13a Insulating adhesive composition, 12b Conductive particle 13 Insulating adhesive layer, 14 Glass substrate, 15 Wiring electrode, 16 IC chip , 17 Bump

<Example 1>
Phenoxy resin (YP-50, manufactured by Nippon Steel Chemical Co., Ltd.) 50 parts by mass, bifunctional acrylate monomer (DCP, manufactured by Shin Nakamura Chemical Co., Ltd.) 12 parts by mass, monofunctional acrylate monomer (A-SA, Shin Nakamura Chemical) Industrial Co., Ltd.) 5 parts by mass, urethane acrylate (U-2PPA, Shin-Nakamura Chemical Co., Ltd.) 15 parts by mass, silica fine particles (Aerosil RY200, Nippon Aerosil Co., Ltd.) 10 parts by mass, phosphate ester acrylate ( 3 parts by mass of PM-2, manufactured by Nippon Kayaku Co., Ltd., 1 part by mass of a silane coupling agent (KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.), and an organic peroxide (Perocta O , manufactured by NOF Corporation) 4 Toluene was added to mass parts so that the solid concentration was 50% to prepare a resin composition. This resin composition was applied onto a PET film as a release film by a bar coater. In the coated material, 4.0 parts by mass of an average particle diameter of 3 μm, a resin core, and Ni / Au plated conductive particles (AUL703, manufactured by Sekisui Chemical Co., Ltd.) were arranged in a single layer. In addition, the electroconductive particle was arranged in the single layer according to the spraying method of Example 1 of Unexamined-Japanese-Patent No. 2009-134914. The coated material on which the conductive particles were arranged was dried by heating in an oven to obtain a conductive particle-containing layer having a thickness of 5 μm. The conductive particle-containing layer had an average particle density of 15,000 particles / mm ² and a minimum melt viscosity of 13000 Pa · s.

25 parts by mass of phenoxy resin (YP-50, manufactured by Nippon Steel Chemical Co., Ltd.), 30 parts by mass of phenoxy resin (jER4004, Mitsubishi Chemical Corporation), 12 parts by mass of bifunctional acrylate monomer (DCP, manufactured by Shin-Nakamura Chemical Co., Ltd.) Parts, monofunctional acrylate monomer (A-SA, Shin-Nakamura Chemical Co., Ltd.) 5 parts by mass, urethane acrylate (U-2PPA, Shin-Nakamura Chemical Co., Ltd.) 20 parts by mass, phosphate ester acrylate (PM- 2, 3 parts by mass of Nippon Kayaku Co., Ltd., 1 part by mass of a silane coupling agent (KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.), and 4 parts by mass of an organic peroxide (Perocta O , manufactured by NOF Corporation) In addition, a resin composition was prepared by adding toluene so that the solid concentration was 50%. This resin composition was applied onto the conductive particle-containing layer by a bar coater and dried by heating in an oven to obtain an insulating adhesive layer having a thickness of 9 μm and a minimum melt viscosity of 800 Pa · s.

Claims (8)

In the connection method of connecting the connection surface on which the wiring electrode of the substrate is formed and the connection surface on which the terminal electrode of the electronic component is formed through an anisotropic conductive film,
The anisotropic conductive film includes a conductive particle-containing layer in which conductive particles are contained in the first insulating adhesive composition, and a second melt viscosity lower than that of the first insulating adhesive composition. And an insulating adhesive layer containing insulating particles in the insulating adhesive composition of
The insulating adhesive layer has the insulating particles protruding from the surface of the insulating adhesive layer,
The ratio of the length of the insulating particles protruding from the surface of the insulating adhesive layer to the average particle diameter of the insulating particles is 30 to 60%,
The compression elastic modulus (10% K value) when the diameter of the insulating particles is displaced by 10% is 4000 N / mm ² or less,
The anisotropic conductive film is temporarily pasted on the substrate by confronting the surface of the insulating adhesive layer from which the insulating particles protrude and the connection surface of the substrate on which the wiring electrodes are formed,
Placing the electronic component on the anisotropic conductive film;
A connection method in which the wiring electrodes of the substrate and the terminal electrodes of the electronic component are anisotropically conductively connected by heat and pressure.   The connection method according to claim 1, wherein the insulating particles have a melting point of 105 to 165 ° C.   The connection method according to claim 1, wherein an average particle diameter of the insulating particles is 3.0 μm to 8.0 μm.   The connection method according to claim 1, wherein the conductive particles are arranged in a single layer or randomly in the conductive particle-containing layer.   The connection method according to claim 1, wherein a minimum melt viscosity of the insulating adhesive layer is lower than a minimum melt viscosity of the conductive particle-containing layer. In the connection structure in which the connection surface on which the wiring electrode of the substrate is formed and the connection surface on which the terminal electrode of the electronic component is formed are connected via an anisotropic conductive film,
The anisotropic conductive film includes a conductive particle-containing layer in which conductive particles are contained in the first insulating adhesive composition, and a second melt viscosity lower than that of the first insulating adhesive composition. And an insulating adhesive layer containing insulating particles in the insulating adhesive composition of
The insulating adhesive layer has the insulating particles protruding from the surface of the insulating adhesive layer,
The ratio of the length of the insulating particles protruding from the surface of the insulating adhesive layer to the average particle diameter of the insulating particles is 30 to 60%,
The compression elastic modulus (10% K value) when the diameter of the insulating particles is displaced by 10% is 4000 N / mm ² or less,
The anisotropic conductive film is temporarily pasted on the substrate by confronting the surface of the insulating adhesive layer from which the insulating particles protrude and the connection surface of the substrate on which the wiring electrodes are formed,
Placing the electronic component on the anisotropic conductive film;
A connection structure formed by connecting the connection surface of the substrate on which the wiring electrode is formed and the terminal electrode of the electronic component by anisotropic conductive connection by heat and pressure. A conductive particle-containing layer in which conductive particles are contained in the first insulating adhesive composition, and a second insulating adhesive composition having a lowest melt viscosity lower than that of the first insulating adhesive composition In an anisotropic conductive film formed by laminating an insulating adhesive layer containing insulating particles,
The insulating adhesive layer has the insulating particles protruding from the surface of the insulating adhesive layer,
The ratio of the length of the insulating particles protruding from the surface of the insulating adhesive layer to the average particle diameter of the insulating particles is 30 to 60%,
An anisotropic conductive film having a compressive elastic modulus (10% K value) when the diameter of the insulating particles is displaced by 10% is 4000 N / mm ² or less. A conductive particle-containing layer in which conductive particles are contained in the first insulating adhesive composition, and a second insulating adhesive composition having a minimum melt viscosity lower than that of the first insulating adhesive composition In the method for producing an anisotropic conductive film in which an insulating adhesive layer containing insulating particles is laminated,
On the release film, the first insulating adhesive composition containing the conductive particles is applied, and the conductive particle-containing layer is formed by drying,
On the conductive particle-containing layer, the first insulating adhesive composition containing the insulating particles is applied and dried to form the insulating adhesive layer,
Spraying the insulating particles on the surface of the insulating adhesive layer;
By laminating, the conductive particles protrude from the surface of the insulating adhesive layer,
The ratio of the length of the insulating particles protruding from the surface of the insulating adhesive layer to the average particle diameter of the insulating particles is 30 to 60%,
The method for producing an anisotropic conductive film, wherein the compressive elastic modulus (10% K value) when the diameter of the insulating particles is displaced by 10% is 4000 N / mm ² or less.

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