JP2013214417A - Circuit connection material, circuit connection material structure and manufacturing method of circuit connection material structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a circuit connection material which can maintain excellent electrical connection between circuit members being connected, even when interconnecting the circuit members with low pressure.SOLUTION: A circuit connection material 50a is interposed between a first circuit member 30 having a first circuit electrode 32 and a second circuit member 40 having a second circuit electrode 42, and connects the first circuit electrode and second circuit electrode electrically by compression. At least one of the first circuit member and second circuit member is an IC chip, and the compression load is 50 MPa or less for the electrode area of the IC chip. The circuit connection material contains conductive particles 10A and an adhesive component 20a, the conductive particle has a metal layer on the surface of a plastic particle, the outermost layer of the metal layer is palladium, and the compression modulus of the conductive particle during 30% compression deformation of the particle diameter is 100-500 kgf/mm.

Description

  The present invention relates to a circuit connection material, a circuit member connection structure, and a method for manufacturing a circuit member connection structure.

  As a method of mounting a liquid crystal driving IC on a glass panel for a liquid crystal display, CHIP-ON-GLASS mounting (hereinafter referred to as “COG mounting”) or CHIP-ON-FLEX mounting (hereinafter referred to as “COF mounting”). Is widely used. COG mounting is a method in which a liquid crystal driving IC is directly bonded onto a glass panel. On the other hand, COF mounting is a method in which a liquid crystal driving IC is joined to a flexible tape having metal wiring, and this is joined to a glass panel.

  In the above COG mounting and COF mounting, it is common to use an adhesive composition having anisotropic conductivity as a circuit connecting material. In this adhesive composition, conductive particles are dispersed in an adhesive component. Examples of the circuit connecting material using such an adhesive composition include an adhesive film described in Patent Document 1.

International Publication No. 08/056773 Pamphlet

  By the way, in recent years, with the high definition of liquid crystal displays, the density of circuit electrodes formed on circuit members has been increased. For this reason, circuit electrodes tend to be further miniaturized, that is, high definition such as multiple electrodes and narrow pitches, and high connection reliability in high definition liquid crystal modules is required.

  On the other hand, since the total area of the circuit electrodes in the circuit members tends to increase due to the increase in the number of circuit electrodes, the pressure applied to the circuit electrodes is dispersed when the circuit members are connected to each other. Connection reliability tends to be required.

  In addition, with the recent thinning of liquid crystal modules, liquid crystal driving ICs and glass panels are becoming thinner, preventing the circuit members themselves from being damaged by the pressure applied when connecting circuit members. Therefore, a low pressure connection tends to be required.

  However, in the above conventional circuit connection material, the contact between the circuit electrode and the conductive particles in the adhesive composition for circuit connection is insufficient at the time of low-pressure connection, and the circuit electrodes are opposed to each other when the circuit members are connected to each other. There is a problem that an insulating adhesive component easily remains in between, resulting in an increase in connection resistance between the circuits and a connection failure.

  Therefore, the present invention provides a circuit connection material that can maintain good electrical connectivity and long-term reliability of electrical characteristics between connected circuit members even when the circuit members are connected at a low pressure. The purpose is to provide. Moreover, an object of this invention is to provide the circuit member connection structure to which the circuit member was connected using said circuit connection material, and the manufacturing method of the said circuit member connection structure.

The present invention interposes between a first circuit member having a first circuit electrode and a second circuit member having a second circuit electrode, and pressurizes the first circuit electrode and the second circuit electrode. A circuit connection material for electrically connecting to each other, wherein at least one of the first circuit member and the second circuit member is an IC chip, and the load in pressurization is relative to the electrode area of the IC chip 50 MPa or less, the circuit connecting material contains conductive particles and an adhesive component, the conductive particles have a metal layer on the surface of the plastic particles, the outermost layer of the metal layer is palladium, and the particles in the conductive particles Provided is a circuit connecting material having a compressive elastic modulus of 100 to 500 kgf / mm ² at 30% diameter compression deformation. Here, the load in the pressurization may be 10 MPa or less with respect to the chip area of the IC chip.

In addition, the load in the said pressurization is the applied pressure computed from the following formulas according to the electrode area of an IC chip.
Applied pressure = (IC chip electrode area) x (Target pressure)
In the present invention, the target pressure is 50 MPa or less.

The present invention also interposes between a first circuit member having a first circuit electrode and a second circuit member having a second circuit electrode and pressurizing the first circuit electrode and the second circuit. A circuit connection material for electrically connecting an electrode, wherein at least one of the first circuit member and the second circuit member is an IC chip, and the load in pressurization is relative to the chip area of the IC chip. 10 MPa or less, the circuit connection material contains conductive particles and an adhesive component, the conductive particles have a metal layer on the surface of the plastic particles, and the outermost layer of the metal layer is palladium, and the particles in the conductive particles Provided is a circuit connecting material having a compressive elastic modulus of 100 to 500 kgf / mm ² at 30% diameter compression deformation.

  The circuit connection material of the present invention has the above-described configuration, so that even when the circuit members are connected at a low pressure, the electrical connection between the circuit members to be connected and the long-term reliability of the electrical characteristics are good. Can be kept in. The reason why such an effect is achieved by the circuit connection material of the present invention is not necessarily clear, but the present inventors presume this reason as 1) and 2) below. However, the reason is not limited to this.

  1) The circuit connection material of the present invention contains conductive particles having a metal layer on the surface of plastic particles, and the outermost layer of the metal layer being palladium. Since palladium (Pd), which is the outermost layer of the conductive particles, is harder than other conductive materials such as Au, the outermost layer of the conductive particles is more likely to bite into the circuit electrode, and the conductive The contact area between the particles and the circuit electrode can be increased, which makes it possible to obtain better electrical connection and long-term reliability of electrical characteristics even when connected at a low pressure.

2) The conductive particles in the circuit connecting material of the present invention have a compressive elastic modulus of 100 to 500 kgf / mm ² at 30% compression deformation of the particle diameter. Since such an electrically conductive particle is likely to bite into the outermost layer of the electrically conductive particle with respect to the circuit electrode, sufficient electrical connection can be obtained. In addition, since such conductive particles are deformed into a sufficiently flat shape at the time of connection, even if the distance between the circuit electrodes becomes wide due to temperature fluctuations, the conductive particles are spaced from each other. As a result, long-term connection reliability can be ensured.

  In addition, according to the circuit connection material of the present invention, even when COG mounting or COF mounting using a fine circuit member having a large number of connection terminals is performed, electrical connection between the circuit members to be connected is performed. It is possible to maintain good connectivity and prevent the thinned circuit member from being broken by the pressure applied at the time of connection.

  The circuit connection material of the present invention preferably contains a film forming material, an epoxy resin, and a latent curing agent as an adhesive component in the circuit connection material.

  According to such a circuit connection material, electrical connectivity and long-term reliability of electrical characteristics when circuit members are connected at a low pressure are further improved.

  The present invention also includes a first circuit member having a first circuit electrode, at least one of which is an IC chip, and a second circuit member having a second circuit electrode, the first circuit electrode and the second circuit member. Electrodes are arranged opposite to each other, and the circuit connection material is interposed between the first circuit electrode and the second circuit electrode arranged opposite to each other, and the load is 50 MPa or less with respect to the electrode area of the IC chip. There is provided a circuit member connection structure in which pressure is applied under conditions to electrically connect a first circuit electrode and a second circuit electrode.

  Since such a circuit member connection structure uses the circuit connection material, it is excellent in electrical connectivity and long-term connection reliability.

  In the circuit member connection structure of the present invention, at least one of the first circuit electrode and the second circuit electrode is gold, silver, tin, a platinum group metal, aluminum, titanium, molybdenum, chromium, indium-tin. It is preferable to have at least one circuit electrode selected from the group consisting of oxide (ITO) and indium-zinc oxide (IZO).

  According to such a circuit member connection structure, electrical connectivity and long-term connection reliability are further improved.

  In the circuit member connection structure of the present invention, at least one of the first circuit member and the second circuit member is coated or adhered with at least one selected from the group consisting of silicon nitride, silicone compounds, and polyimide resins. It is preferable that

  According to such a circuit member connection structure, electrical connectivity and long-term connection reliability are further improved.

  The present invention also includes a first circuit member having a first circuit electrode, at least one of which is an IC chip, and a second circuit member having a second circuit electrode, the first circuit electrode and the second circuit member. Electrodes are arranged opposite to each other, and the circuit connection material is interposed between the first circuit electrode and the second circuit electrode arranged opposite to each other, and the load is 50 MPa or less with respect to the electrode area of the IC chip. A method of manufacturing a circuit member connection structure including a step of applying pressure under conditions to electrically connect a first circuit electrode and a second circuit electrode is provided.

  According to such a manufacturing method, it is possible to manufacture a circuit member connection structure having good electrical connectivity and long-term connection reliability.

  According to the present invention, there is provided a circuit connection material capable of maintaining good electrical connectivity and long-term reliability of electrical characteristics between connected circuit members even when the circuit members are connected at a low pressure. Can be provided. Further, according to such a circuit connecting material, even when COG mounting or COF mounting using a fine circuit member having a large number of connection terminals is performed, electrical connection between the circuit members to be connected is performed. It is possible to maintain good connectivity and prevent the thinned circuit member from being broken by the pressure applied at the time of connection. Moreover, according to this invention, the circuit member connection structure to which the circuit member was connected using said circuit connection material, and the manufacturing method of the said circuit member connection structure are provided.

It is a schematic cross section which shows one Embodiment of the circuit member connection structure which concerns on this invention. It is a schematic cross section which shows one Embodiment of the electroconductive particle which concerns on this invention. It is a schematic cross section which shows one Embodiment of the electroconductive particle which concerns on this invention. It is sectional drawing which shows the state in which the circuit connection material which concerns on this embodiment is provided on the film-form support body. It is process drawing which shows one Embodiment of the connection method of the circuit member which concerns on this invention with a schematic sectional drawing. It is a schematic cross section which shows the circuit connection material of the two-layer structure supported by the support body. It is a top view which shows an example of the electrode of an IC chip.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant descriptions may be omitted. Further, the positional relationship such as up, down, left and right is based on the positional relationship shown in the drawings unless otherwise specified. Furthermore, for convenience of illustration, the dimensional ratios in the drawings do not necessarily match those described.

The circuit connection material according to the present embodiment is interposed between a first circuit member having a first circuit electrode and a second circuit member having a second circuit electrode, and the first circuit electrode is applied by pressurization. Is used as an anisotropic conductive adhesive for circuit connection for electrically connecting the second circuit electrode and the second circuit electrode. Here, at least one of the first circuit member and the second circuit member is an IC chip, and the load in the pressing is 50 MPa or less with respect to the electrode area of the IC chip and / or the chip of the IC chip. It is 10 MPa or less with respect to an area. Furthermore, the circuit connection material according to the present embodiment contains conductive particles and an adhesive component, the conductive particles have a metal layer on the surface of the plastic particles, the outermost layer of the metal layer is palladium, and the conductive material The compression elastic modulus at the time of 30% compression deformation of the particle diameter of the particles is 100 to 500 kgf / mm ² .

  According to such a circuit connection material, even when the circuit members are connected at a low pressure, the electrical connectivity between the circuit members to be connected and the long-term reliability of the electrical characteristics can be maintained well. . Further, according to such a circuit connecting material, even when COG mounting or COF mounting using a fine circuit member having a large number of connection terminals is performed, electrical connection between the circuit members to be connected is performed. It is possible to maintain good connectivity and prevent the thinned circuit member from being broken by the pressure applied at the time of connection.

  Here, the compression elastic modulus at 30% compression deformation of the particle diameter of the conductive particles is measured as follows. Using a micro compression tester (for example, H-100 micro hardness tester manufactured by Fischer Instruments Co., Ltd.), the conductive particles were applied to a smooth indenter end face of a diamond cylinder having a diameter of 50 μm, a compression speed of 2.6 mN / sec, and a maximum test load. Compress under conditions of 10 g. The load value (N) and compression displacement (mm) at this time are measured.

From the measured value obtained, the 30% compression elastic modulus of the particle diameter of the conductive particles is obtained by the following formula. K value (N / mm ² ) = (3/2 ^1/2 ) · F · S ⁻³ / ² · R ^−1/2
F: Load value when conductive particles are 30% compressively deformed (N)
S: Compression displacement (mm) when conductive particles are 30% compressed and deformed
R: radius of conductive particles (mm)

The compression modulus at the time of 30% compression deformation of the particle diameter of the conductive particles is preferably 150 to 400 kgf / mm ² . The compression elastic modulus of the conductive particles can be adjusted, for example, by changing the type of monomer used for the synthesis of the plastic particles and the amount of the monomer.

  The circuit member connection structure according to the present embodiment includes a first circuit member having a first circuit electrode and a second circuit member having a second circuit electrode, the first circuit electrode and the first circuit electrode. Two circuit electrodes are arranged to face each other, the circuit connection material is interposed between the first circuit electrode and the second circuit electrode arranged to face each other, and the first circuit electrode and the second circuit electrode are pressed. The second circuit electrode is electrically connected. Here, at least one of the first circuit member and the second circuit member is an IC chip, and the load in the pressurization is 50 MPa or less with respect to the electrode area of the IC chip and / or the chip area of the IC chip. Is 10 MPa or less. Since such a circuit member connection structure uses the circuit connection material, it is excellent in electrical connectivity and long-term connection reliability.

  FIG. 1 is a schematic cross-sectional view showing an embodiment of a circuit member connection structure according to the present invention. The circuit member connection structure 100 shown in FIG. 1 includes a first circuit member 30 and a second circuit member 40 that face each other, and the circuit member connection structure 100 includes a first circuit member 30 and a second circuit member 40. A connecting portion 50a for connecting them is provided between them.

  The first circuit member 30 includes a circuit board (first circuit board) 31 and connection terminals (first connection terminals) 32 formed on the main surface 31 a of the circuit board 31. The second circuit member 40 includes a circuit board (second circuit board) 41 and connection terminals (second connection terminals) 42 formed on the main surface 41 a on the circuit board 41.

  Specific examples of the first circuit member 30 and the second circuit member 40 include, for example, chip components such as IC chips (semiconductor chips), resistor chips, capacitor chips, tape carrier packages (TCP), flexible circuit boards ( FPC), a printed wiring board, and a glass substrate. These circuit members are usually provided with one or more (preferably many) connection terminals (circuit electrodes). The combination of circuit members to be connected is not particularly limited, except that at least one of the first circuit member 30 and the second circuit member 40 is an IC chip. The IC chip and the chip mounting substrate, and the IC chip and the glass substrate. And a combination of an IC chip and a flexible tape.

  An insulating layer may be provided on the main surface 31a and / or the main surface 41a. The material constituting the insulating layer is not particularly limited as long as it is an insulating material, and examples thereof include organic insulating substances, silicon dioxide, silicon nitride (silicon nitride), and the like. Moreover, it is preferable that the main surface 31a and / or the main surface 41a are coated or attached with at least one selected from the group consisting of silicon nitride, a silicone compound, and a polyimide resin. Such a circuit member is bonded with a better adhesive strength by the circuit connection material according to the present embodiment.

  The material of the circuit board 31 and the circuit member 41a is not particularly limited, and examples thereof include an organic insulating material, glass, and silicon.

  The connection terminal 32 and the connection terminal 42 have circuit electrodes. At least one of the connection terminal 32 and the connection terminal 42 is gold, silver, tin, platinum group metal, aluminum, titanium, molybdenum, chromium, indium-tin oxide (ITO), and indium-zinc oxide (IZO). It is preferable to have at least one circuit electrode selected from the group consisting of: The surface of each connection terminal 32 and connection terminal 42 is gold, silver, tin, platinum group metal, aluminum, titanium, molybdenum, chromium, indium-tin oxide (ITO), and indium-zinc oxide (IZO). It may be composed of at least one selected from the group consisting of Here, the material of the circuit electrode may be the same or different in all the circuit electrodes. Moreover, the material of the surface of a connection terminal may be the same in all the connection terminals, and may differ.

  It is preferable that the connection terminal 32 and the connection terminal 42 have flat surfaces facing each other. Here, “the surface of the connection terminal is flat” means that the surface unevenness is sufficiently small, and the surface unevenness is preferably 20 nm or less.

  The connection part 50a includes a cured product 20a of an adhesive component contained in the circuit connection material and conductive particles 10A. And in the circuit member connection structure 100, the connecting terminal 32 and the connecting terminal 42 which oppose are electrically connected via 10 A of electrically-conductive particles. That is, the conductive particles 10 </ b> A are in direct contact with both the connection terminal 32 and the connection terminal 42.

  For this reason, the connection resistance between the connection terminal 32 and the connection terminal 42 is sufficiently reduced, and a good electrical connection between the connection terminal 32 and the connection terminal 42 becomes possible. On the other hand, the hardened | cured material 20a has electrical insulation, and insulation is ensured between adjacent connection terminals. Therefore, the flow of current between the connection terminal 32 and the connection terminal 42 can be made smooth, and the functions of the circuit can be fully exhibited.

  Next, the conductive particles in the present embodiment will be described in detail.

  FIG. 2 is a schematic cross-sectional view showing an embodiment of conductive particles according to the present invention. The conductive particles 10 are composed of a core (plastic particle) 1a constituting a central portion and a conductive layer (metal layer) 1b formed on the surface of the core 1a.

  The core 1a, that is, the material constituting the plastic particles is preferably one that is deformed by heating and / or pressurization. If the core 1a is deformed, when the conductive particles 10 are pressed by the connection terminal 32 and the connection terminal 42, the contact area with the connection terminal increases. Further, irregularities on the surfaces of the connection terminal 32 and the connection terminal 42 can be absorbed. Therefore, the connection reliability between the connection terminals is improved.

  Examples of the material constituting the core 1a include polystyrene, polydivinylbenzene, polyacrylic ester, epoxy resin, phenol resin, and benzoguanamine resin. Moreover, you may use what added various additives, such as a crosslinking material, a hardening | curing agent, and anti-aging agent, with respect to the material which has these as a main component.

  Moreover, the polymer obtained by superposing | polymerizing 1 type (s) or 2 or more types from the following monomers can be used. Dimethylol-tricyclodecane di (meth) acrylate, 1,3-adamantanediol di (meth) acrylate, isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentanyl (meth) acrylate, 2-methyl- 2-adamantyl (meth) acrylate, 2-ethyl-2-adamantyl (meth) acrylate, 3-hydroxy-1-adamantyl (meth) acrylate, polytetramethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate , Tetramethylol methane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acryl , Butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ethylene glycol (meth) acrylate, trifluoroethyl (meth) acrylate, pentafluoropropyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) Acrylate, dicyclopentenyl (meth) acrylate, dicyclopentanyl (meth) acrylate, 2-methyl-2-adamantyl (meth) acrylate, 2-ethyl-2-adamantyl (meth) acrylate or 3-hydroxy-1-adamantyl Acrylic monomers such as (meth) acrylate; vinyl ether compounds such as tricyclodecane vinyl ether or tricyclodecane monomethyl vinyl ether; In this specification, (meth) acrylate means methacrylate or acrylate.

  The core 1a may be made of the same or different material between particles, and one kind of material may be used alone or a mixture of two or more kinds of materials may be used for the same particle.

  The average particle diameter of the core 1a can be appropriately designed according to the use, etc., but is preferably 0.5 to 20 μm, more preferably 1 to 10 μm, and further preferably 2 to 5 μm. preferable. When conductive particles are produced using nuclei having an average particle diameter of less than 0.5 μm, secondary aggregation of the particles occurs, the insulation between adjacent connecting terminals tends to be insufficient, and the average particle diameter is When conductive particles are produced using a nucleus exceeding 20 μm, the insulation between adjacent connection terminals tends to be insufficient due to the size.

  The conductive layer 1b, that is, the metal layer is a layer provided so as to cover the surface of the core 1a, and is a conductive layer. From the viewpoint of ensuring sufficient conductivity, the conductive layer 1b preferably covers the entire surface of the core 1a.

  Examples of the material of the conductive layer 1b include gold, silver, platinum, nickel, copper, palladium, alloys thereof, and alloys such as solder containing tin. In order to obtain a sufficient pot life, gold, silver, platinum, palladium or an alloy thereof is preferable, and palladium or gold is more preferable. In addition, these can be used individually by 1 type or in combination of 2 or more types.

  The thickness of the conductive layer 1b can be appropriately designed according to the material and application used for this, but is preferably 50 to 200 nm, and more preferably 80 to 150 nm. When the thickness is less than 50 nm, there is a tendency that a sufficiently low resistance value of the connection portion cannot be obtained. On the other hand, the production efficiency of the conductive layer 1b having a thickness exceeding 200 nm tends to decrease.

  The conductive layer 1b can be composed of one layer or two or more layers. In any case, the surface layer (outermost layer) of the conductive layer (metal layer) 1b is used from the viewpoint of preserving the circuit connection material produced using this and securing long-term connection reliability in low-pressure connection. It shall be composed of palladium. When the conductive layer 1b is composed of a single layer made of palladium, the thickness is preferably 10 to 200 nm in order to obtain a sufficiently low resistance value at the connection portion.

  On the other hand, when the conductive layer 1b is composed of two or more layers, the outermost layer of the conductive layer 1b is composed of palladium. The layer between the outermost layer and the core 1a is, for example, nickel, copper, tin, or these You may comprise by the metal layer containing these alloys. In this case, the thickness of the palladium metal layer constituting the outermost layer of the conductive layer 1b is preferably 30 to 200 nm from the viewpoint of storage stability of the adhesive composition. Nickel, copper, tin, or an alloy thereof may generate free radicals by redox action. For this reason, when the thickness of the outermost layer made of palladium is less than 30 nm, when used together with an adhesive component having radical polymerizability, it tends to be difficult to sufficiently prevent the influence of free radicals.

  Examples of the method for forming the conductive layer 1b on the surface of the core 1a include electroless plating treatment and physical coating treatment. From the viewpoint of easy formation of the conductive layer 1b, the conductive layer 1b made of metal is preferably formed on the surface of the core 1a by electroless plating.

  FIG. 3 is a schematic cross-sectional view showing an embodiment of conductive particles according to the present invention. The conductive particles 10A include a core (base particle) 1a constituting a central portion, a conductive layer 1b provided on the surface of the core 1a, and a plurality of layers provided on the surface on the conductive layer 1b. Insulating particles 2A. According to such a conductive particle, the insulation between adjacent connection terminals can be further enhanced. Hereinafter, the central particle composed of the core 1a and the conductive layer 1b is referred to as a core particle 1.

  The insulating particles 2A are made of an organic polymer compound. As the organic polymer compound, those composed of a polymer of a radical polymerizable substance are preferable. In this case, the insulating particles 2A can easily adhere to the surface of the core particles 1 of the conductive particles 10A, and the insulation between the adjacent connection terminals can be further improved. Examples of the method for producing the insulating particles 2A include a seed polymerization method.

  The radically polymerizable substance is a substance having a functional group that is polymerized by radicals, and examples of such a radically polymerizable substance include (meth) acrylate compounds and maleimide compounds. The radically polymerizable substance may be used in the state of a monomer or an oligomer, and the monomer and the oligomer can be used in combination.

  Specific examples of the (meth) acrylate compound include methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, isobutyl (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, Trimethylolpropane tri (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, 2-hydroxy-1,3-di (meth) acryloxypropane, 2,2-bis [4-((meth) acryloxymethoxy) Phenyl] propane, 2,2-bis [4-((meth) acryloxypolyethoxy) phenyl] propane, dicyclopentenyl (meth) acrylate, tricyclodecanyl (meth) acrylate, tris ((meth) acryloyloxy Echi ) Isocyanurate, urethane (meth) acrylate.

  These can be used alone or in admixture of two or more. Further, if necessary, a polymerization inhibitor such as hydroquinone or methyl ether hydroquinone may be used. Moreover, it is preferable that a (meth) acrylate compound has at least 1 substituent selected from the group which consists of a dicyclopentenyl group, a tricyclodecanyl group, and a triazine ring from the point which improves heat resistance.

  The maleimide compound contains at least two maleimide groups in the molecule, and examples of such maleimide compounds include 1-methyl-2,4-bismaleimidebenzene, N, N′-m-phenylene. Bismaleimide, N, N′-p-phenylenebismaleimide, N, N′-m-toluylene bismaleimide, N, N′-4,4-biphenylenebismaleimide, N, N′-4,4- (3 , 3′-dimethylbiphenylene) bismaleimide, N, N′-4,4- (3,3′-dimethyldiphenylmethane) bismaleimide, N, N′-4,4- (3,3′-diethyldiphenylmethane) bis Maleimide, N, N′-4,4-diphenylmethane bismaleimide, N, N′-4,4-diphenylpropane bismaleimide, N, N′-3,3 ′ Diphenylsulfone bismaleimide, N, N′-4,4-diphenyl ether bismaleimide, 2,2-bis (4- (4-maleimidophenoxy) phenyl) propane, 2,2-bis (3-s-butyl-4, 8- (4-maleimidophenoxy) phenyl) propane, 1,1-bis (4- (4-maleimidophenoxy) phenyl) decane, 4,4′-cyclohexylidene-bis (1- (4-maleimidophenoxy)- Examples include 2-cyclohexylbenzene, 2,2-bis (4- (4-maleimidophenoxy) phenyl) hexafluoropropane, etc. These can be used alone or in admixture of two or more.

  When circuit members are connected by heating and pressing, the softening point of the organic polymer compound that constitutes the insulating particles 2A is preferably equal to or higher than the heating temperature when the circuit members are connected. When the softening point is lower than the heating temperature at the time of connection, the insulating particles 2A are excessively deformed at the time of connection, so that there is a tendency that good electrical connection cannot be obtained.

  The degree of crosslinking of the organic polymer compound that constitutes the insulating particles 2A is preferably 5 to 20%, more preferably 5 to 15%, and still more preferably 8 to 13%. An organic polymer compound having a crosslinking degree within the above range has a characteristic that both connection reliability and insulation are excellent as compared with an organic polymer compound outside the range. Therefore, if the degree of crosslinking is less than 5%, the insulation between adjacent electrode circuits tends to be insufficient. On the other hand, when the degree of cross-linking exceeds 20%, it tends to be difficult to achieve both a sufficiently low initial resistance value of the connecting portion and suppression of a rise in resistance value over time.

  The degree of crosslinking of the organic polymer compound can be adjusted by the composition ratio of the crosslinkable monomer and the non-crosslinkable monomer. The degree of crosslinking as used in the present invention means a theoretical calculated value based on the composition ratio (charged mass ratio) of the crosslinkable monomer and the non-crosslinkable monomer. That is, it is a value calculated by dividing the charged mass of the crosslinkable monomer blended in synthesizing the organic polymer compound by the total charged mass ratio of the crosslinkable and non-crosslinkable monomers.

  The gel fraction of the organic polymer compound constituting the insulating particles 2A is preferably 90% or more, and more preferably 95% or more. When the gel fraction is less than 90%, when the adhesive composition is prepared by dispersing the conductive particles 10A in the adhesive component, the insulation resistance of the adhesive component tends to decrease with time.

  Here, the gel fraction is an index indicating the resistance of the organic polymer compound to the solvent, and the measurement method will be described below. The mass (mass A) of the organic polymer compound (sample to be measured) whose gel fraction is to be measured is measured. A sample to be measured is placed in a container, and a solvent is put in it. At a temperature of 23 ° C., the sample to be measured is immersed in a solvent for 24 hours with stirring. Thereafter, the solvent is removed by volatilization or the like, and the mass (mass B) of the sample to be measured after stirring and immersion is measured. The gel fraction (%) is a value calculated by the equation (mass B / mass A × 100).

  The solvent used for measuring the gel fraction is toluene. In general, toluene, xylene, ethyl acetate, butyl acetate, methyl ethyl ketone, methyl isobutyl ketone, and tetrahydrofuran are used for the preparation of the adhesive composition solution. One of these can be used alone or in admixture of two or more.

  The average particle diameter of the insulating particles 2A can be appropriately designed according to the use, etc., but is preferably 50 to 500 nm, more preferably 100 to 450 nm, and further preferably 200 to 400 nm. . If the average particle size is less than 50 nm, the insulation between adjacent circuits tends to be insufficient. On the other hand, if the average particle size exceeds 500 nm, the sufficiently low initial resistance value and the resistance value of the connection portion increase with time. It tends to be difficult to achieve both suppression.

  The insulating particles 2A are formed on the surface of the core particle 1 so that the coverage defined by the following formula (1) is 20 to 60%. The coverage is preferably 35 to 45%, and more preferably 38 to 42%. If the coverage is less than 20%, insulation between adjacent connection terminals becomes insufficient. On the other hand, if the coverage exceeds 60%, sufficiently low initial resistance value and suppression of increase in resistance value with time are suppressed. It will be difficult to achieve both. The plurality of insulating particles 2 </ b> A covering the core particle 1 are preferably sufficiently dispersed on the surface of the core particle 1.

  The coverage here is based on the following measured values obtained by observation with a differential scanning electron microscope (magnification 8000 times). That is, the coverage is a value calculated based on the particle sizes of the core particles and the insulating particles and the number of insulating particles attached to one core particle. Measurement is performed as described above for 50 arbitrarily selected particles, and the average value is calculated.

The particle diameter of the core particle 1 is measured as follows. That is, one core particle is arbitrarily selected, and this is observed with a differential scanning electron microscope, and its maximum diameter and minimum diameter are measured. The square root of the product of the maximum diameter and the minimum diameter is defined as the particle diameter of the particle. The particle size of 50 arbitrarily selected core particles is measured as described above, and the average value is defined as the particle size (D ₁ ) of the core particle 1. As for the particle diameter of the insulating particles 2A, the particle diameters of 50 arbitrary insulating particles are measured in the same manner, and the average value is defined as the particle diameter (D ₂ ) of the insulating particles 2A.

  The number of insulating particles included in one conductive particle is measured as follows. That is, one conductive particle whose surface is partially covered with a plurality of insulating particles 2A is arbitrarily selected. And this is imaged with a differential scanning electron microscope, and the number of the insulating particles adhering on the core particle surface which can be observed is counted. The number of insulating particles adhering to one core particle is calculated by doubling the obtained count number. The number of insulating particles is measured as described above for 50 arbitrarily selected conductive particles, and the average value is defined as the number of insulating particles included in one conductive particle.

The total surface area of the core particle of the formula (1) means the surface area of a sphere having the diameter D ₁ described above. On the other hand, the area of a portion covered with an insulating coating of core particles the surface is obtained by multiplying the number of insulating particles on the value of the area of a circle the D ₂ diameter provided in one of the conductive particles Mean value.

The average particle diameter _{D 2} and the ratio of the average particle diameter _{D 1} of the nucleus particles 1 of the insulating particles 2A _(D 2 / _{D 1)} is preferably 1 / 40-1 / 6, 1/20 to 1 / 8 is more preferable. If D ₂ / D ₁ is less than 1/40, the insulation between adjacent circuits tends to be insufficient. On the other hand, if it exceeds 1/6, it tends to be difficult to achieve both the sufficiently low initial resistance value of the connection portion and the suppression of the increase in resistance value over time.

  The insulating covering formed on the surface of the core particle 1 is not limited to a spherical one like the insulating particle 2A. The insulating covering may be an insulating layer made of the same material as the insulating particles 2A. For example, the conductive particle 10 </ b> B shown in FIG. 3 includes an insulating layer 2 </ b> B partially provided on the surface of the core particle 1.

  The insulating layer 2B is formed on the surface of the core particle 1 so that the coverage defined by the above formula (1) is 20 to 60%. From the viewpoint of more reliably obtaining the effects of the present invention, the coverage is preferably 35 to 45%, and more preferably 38 to 42%. If the coverage is less than 20%, insulation between adjacent connection terminals becomes insufficient. On the other hand, if the coverage exceeds 60%, sufficiently low initial resistance value and suppression of increase in resistance value with time are suppressed. It will be difficult to achieve both. In addition, it is preferable that each covering region of the insulating layer 2 </ b> B covering the core particle 1 is sufficiently dispersed on the surface of the core particle 1. Each covering region may be isolated or may be continuous.

The ratio (T ₂ / D ₁ ) between the thickness T ₂ of the insulating layer 2B and the average particle diameter D ₁ of the core particles 1 is preferably 1/40 to 1/6, and 1/20 to 1/8. It is more preferable that If T ₂ / D ₁ is less than 1/40, the insulation between adjacent circuits tends to be insufficient. On the other hand, if it exceeds 1/6, it tends to be difficult to achieve both the sufficiently low initial resistance value of the connection portion and the suppression of the increase in resistance value over time.

The coverage in the case where the insulating covering is constituted by the insulating layer 2B can be calculated by the following procedure. That is, 50 arbitrarily selected conductive particles can be respectively imaged with a differential scanning electron microscope, and obtained by arithmetically averaging the measured values of the area of the insulating layer adhering on the surface of the core particles that can be observed. it can. Further, the thickness T ₂ of the insulating layer 2B also conductive particles 50 arbitrarily selected captured respectively by a differential scanning electron microscope, the measurement of the thickness of the insulating layer 2B on the surface of each conductive particle It can be obtained by arithmetic averaging.

  As a method of forming an insulating coating (insulating particle 2A or insulating layer 2B) on the surface of the core particle 1, a known method can be used, and a wet method using a chemical change by an organic solvent or a dispersant. And a dry method using a physicochemical change caused by mechanical energy. For example, a spraying method, a high-speed stirring method, a spray dryer method and the like can be mentioned.

  In order to obtain the above-described effect more reliably, it is preferable to provide a plurality of insulating particles 2A having a sufficiently uniform particle diameter on the surface of the core particle 1, thereby forming an insulating coating. Moreover, it is preferable to employ a dry method that does not use a solvent, rather than a wet method in which it is difficult to completely remove the solvent and the dispersant.

  As an apparatus that can form an insulating coating on the surface of the core particle 1 by a dry method, for example, Mechanomill (trade name, manufactured by Tokuju Kogakusho Co., Ltd.), Hybridizer (manufactured by Nara Machinery Co., Ltd., trade name: NHS series) ) And the like. Among these, it is preferable to use a hybridizer because the surface of the core particle 1 can be modified into a suitable state when the insulating coating is formed on the surface of the core particle 1. According to this apparatus, precise coating at the particle level can be performed, and the insulating particles 2A having a sufficiently uniform particle size can be formed on the surface of the core particle 1.

  The shape of the insulating cover can be controlled, for example, by adjusting the conditions of the covering process. The conditions for the coating treatment are, for example, temperature and rotation speed. Moreover, the particle diameter of the insulating particles 2A or the thickness of the insulating layer 2B adjusts the conditions of the coating process and the blending ratio of the core particles 1 to be subjected to the process and the organic polymer compound (material of the insulating coating). Can be done.

  The temperature of the coating treatment (dry method) is preferably 30 to 90 ° C, and more preferably 50 to 70 ° C. Moreover, it is preferable that the rotational speed of a coating process (dry system) is 6000-20000 / min, and it is more preferable that it is 10000-17000 / min.

  The conductive particles 10 are preferably contained in an amount of 0.1 to 30 parts by volume, more preferably 0.1 to 10 parts by volume with respect to 100 parts by volume of the resin component in the circuit connecting material 50. According to this, the short circuit of the adjacent circuit due to excessive conductive particles can be prevented to a higher degree. The “resin component” refers to the adhesive component 20 other than the conductive particles 10 in the circuit connection material 50, and specifically, a film forming material, an epoxy resin, a latent curing agent, and the like described later. Say.

  Next, the adhesive component 20 in the circuit connection material 50 will be described in detail. The adhesive component 20 which is a constituent element of the circuit connection material 50 has adhesiveness. The adhesive component 20 is preferably cured by heat curing or photocuring. The adhesive component 20 preferably contains a film forming material, an epoxy resin, and a latent curing agent. According to this, the above-mentioned effect by this invention can be show | played more reliably.

  The film-forming material is a material that solidifies a liquid material and forms a constituent composition into a film shape, so that the film is easy to handle and imparts mechanical properties that are not easily torn, cracked, or sticky. Yes, it can be handled as a film in a normal state (normal temperature and normal pressure). Examples of the film forming material include phenoxy resin, polyvinyl formal resin, polystyrene resin, polyvinyl butyral resin, polyester resin, polyamide resin, xylene resin, and polyurethane resin. Among these, a phenoxy resin is particularly preferable because of excellent adhesiveness, compatibility, heat resistance, and mechanical strength.

  The phenoxy resin is a resin obtained by reacting a bifunctional phenol and epihalohydrin to a high molecular weight or by polyaddition of a bifunctional epoxy resin and a bifunctional phenol. The phenoxy resin is obtained, for example, by reacting 1 mol of a bifunctional phenol with 0.985 to 1.015 of an epihalohydrin in a non-reactive solvent at a temperature of 40 to 120 ° C. in the presence of an alkali metal hydroxide. Can do.

  Moreover, as a phenoxy resin, especially from the point of the mechanical characteristic and thermal characteristic of resin, the mixing | blending equivalent ratio of bifunctional epoxy resin and bifunctional phenols is epoxy group / phenol hydroxyl group = 1 / 0.9- An organic solvent such as an amide, ether, ketone, lactone, or alcohol having a boiling point of 120 ° C. or higher in the presence of a catalyst such as an alkali metal compound, an organic phosphorus compound, or a cyclic amine compound. Among them, the reaction solid content is preferably 50 parts by weight or less and obtained by polyaddition reaction by heating to 50 to 200 ° C.

  Examples of the bifunctional epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, bisphenol S type epoxy resin, biphenyl diglycidyl ether, and methyl-substituted biphenyl diglycidyl ether. Bifunctional phenols have two phenolic hydroxyl groups. Examples of the bifunctional phenols include hydroquinones, bisphenol A, bisphenol F, bisphenol AD, bisphenol S, bisphenol fluorene, methyl-substituted bisphenol fluorene, bisphenols such as dihydroxybiphenyl and methyl-substituted dihydroxybiphenyl. The phenoxy resin may be modified (for example, epoxy-modified) with a radical polymerizable functional group or other reactive compound. A phenoxy resin may be used independently or may be used in mixture of 2 or more types.

Examples of the epoxy resin contained in the adhesive component 20 include bisphenol-type epoxy resins derived from epichlorohydrin and bisphenol A, bisphenol F, bisphenol AD, and the like, and epoxy novolac resins derived from epichlorohydrin and phenol novolac or cresol novolac. And various epoxy compounds having two or more glycidyl groups in one molecule, such as naphthalene-based epoxy resins having a skeleton containing a naphthalene ring, glycidylamine, glycidyl ether, biphenyl, alicyclic, and the like. These may be used individually by 1 type, or may mix and use 2 or more types. For these epoxy resins, it is preferable to use a high-purity product in which impurity ions (Na ⁺ , Cl ^−, etc.), hydrolyzable chlorine and the like are reduced to 300 ppm or less, in order to prevent electron migration.

  The latent curing agent may be any one that can cure an epoxy resin, and as such a latent curing agent, an anionic polymerizable catalytic curing agent, a cationic polymerizable catalytic curing agent, Examples include polyaddition type curing agents. These can be used alone or as a mixture of two or more. Of these, anionic or cationic polymerizable catalyst-type curing agents are preferred because they are excellent in rapid curability and do not require chemical equivalent considerations.

  Examples of the anionic or cationic polymerizable catalyst-type curing agent include imidazole, hydrazide, boron trifluoride-amine complex, sulfonium salt, amine imide, diaminomaleonitrile, melamine and derivatives thereof, polyamine salt, dicyandiamide and the like. These modifications can also be used. Examples of the polyaddition type curing agent include polyamines, polymercaptans, polyphenols, and acid anhydrides.

  When a tertiary amine or imidazole is blended as an anionic polymerizable catalyst-type curing agent, the epoxy resin is cured by heating at a temperature of about 160 ° C. to 200 ° C. for several tens of seconds to several hours. For this reason, the pot life is relatively long, which is preferable.

  As the cationic polymerizable catalyst-type curing agent, for example, a photosensitive onium salt (mainly used is an aromatic diazonium salt, an aromatic sulfonium salt, or the like) that cures an epoxy resin by energy ray irradiation. Moreover, there are aliphatic sulfonium salts and the like that are activated by heating to cure the epoxy resin. This type of curing agent is preferable because it has a feature of fast curing.

  When these latent hardeners are coated with a polymer material such as polyurethane or polyester, a metal thin film such as nickel or copper, an inorganic material such as calcium silicate, etc. This is preferable because it can be extended.

  The adhesive component 20 may further include a polymer or copolymer having at least one selected from the group consisting of (meth) acrylic acid, (meth) acrylic acid ester, and (meth) acrylic acid nitrile as a monomer component. Good. Here, since it is excellent in stress relaxation, it is preferable to use together the copolymer type | system | group (meth) acrylic rubber containing the glycidyl (meth) acrylate containing a glycidyl ether group. The molecular weight (weight average molecular weight) of these (meth) acrylic rubbers is preferably 200,000 or more from the viewpoint of increasing the cohesive strength of the adhesive component.

  The adhesive component 20 may further contain a filler, a softener, an accelerator, an anti-aging agent, a flame retardant, a pigment, a thixotropic agent, a coupling agent, a phenol resin, a melamine resin, isocyanates, and the like. it can.

  In the case where the adhesive component 20 contains a filler, it is preferable because connection reliability and the like are improved. The filler can be used if its maximum diameter is smaller than the particle diameter of the conductive particles 10. The blending amount of the filler is preferably in the range of 5 to 60 parts by volume with respect to 100 parts by volume of the total amount of the adhesive component 20. If it exceeds 60 parts by volume, the effect of improving the reliability may be saturated, and if it is less than 5 parts by volume, the effect of addition is small.

  As the coupling agent, a compound containing a ketimine, vinyl group, acrylic group, amino group, epoxy group or isocyanate group is preferable because the adhesiveness is improved.

  Specifically, as the silane coupling agent having an amino group, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltrimethoxysilane. Examples include ethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, and the like. Examples of the silane coupling agent having ketimine include those obtained by reacting the above silane coupling agent having an amino group with a ketone compound such as acetone, methyl ethyl ketone, and methyl isobutyl ketone.

  The cured product of the adhesive component 20 preferably has a storage elastic modulus E ′ at a measurement temperature of 40 ° C. and a frequency of 10 Hz of 0.5 to 4.0 GPa, more preferably 1.0 to 3.0 GPa. . The cured product of the circuit member connecting adhesive film having such a storage elastic modulus E ′ has high cohesive force and low internal stress. Therefore, in the circuit member connection structure in which the circuit members are connected using such an adhesive film for connecting circuit members, the circuit members are firmly bonded to each other, and the conduction characteristics are further improved. In addition, when the storage elastic modulus is less than 0.5 GPa, the cohesive force of the components in the cured product of the adhesive film is low as compared with the case where the storage elastic modulus is in the above range, and the connection portion when connecting the circuit members There is a tendency for the electrical resistance of the to increase. In addition, when the storage elastic modulus exceeds 4.0 GPa, the cohesive force of the components in the cured product of the adhesive film is higher than that in the above range, while the cured product itself becomes brittle. Toughness may be reduced. In that case, the peeling or destruction of the adhesive occurs due to the distortion of the circuit member due to the internal stress generated after the connection of the circuit member or the deformation of the circuit member under the long-term environmental test. Resistance tends to increase.

  FIG. 4 is a cross-sectional view showing a state in which the circuit connection material 50 according to the present embodiment is provided on a film-like support 60. Examples of the support 60 include a polyethylene terephthalate film (PET film), a polyethylene naphthalate film, a polyethylene isophthalate film, a polybutylene terephthalate film, a polyolefin film, a polyacetate film, a polycarbonate film, a polyphenylene sulfide film, a polyamide film, and ethylene. -Various films such as a vinyl acetate copolymer film, a polyvinyl chloride film, a polyvinylidene chloride film, a synthetic rubber film, and a liquid crystal polymer film can be used. You may use the support body which gave the corona discharge process, the anchor coat process, the antistatic process, etc. with respect to the surface of said film as needed.

  When using the circuit connection material 50, the surface of the support 60 may be coated with a release treatment agent as necessary so that the support 60 can be easily peeled from the circuit connection material 50. Various release treatment agents such as silicone resins, copolymers of silicone and organic resins, alkyd resins, amino alkyd resins, resins having long chain alkyl groups, resins having fluoroalkyl groups, shellac resins, etc. Can be used.

  The film thickness of the support 60 is not particularly limited, but is preferably 4 to 200 μm in consideration of storage and convenience of use of the produced circuit connection material 50, and further the material cost. In consideration of productivity, the thickness is more preferably 15 to 75 μm.

[Circuit member connection method]
FIG. 5 is a process diagram showing an embodiment of a circuit member connection method according to the present invention in a schematic sectional view. In this embodiment, the connection structure is manufactured by thermosetting the circuit connection material.

  First, the first circuit member 30 and the circuit connection material 50 described above are prepared. The thickness of the circuit connection material 50 is preferably 5 to 50 μm. If the thickness of the circuit connection material 50 is less than 5 μm, the circuit connection material 50 tends to be insufficiently filled between the circuit members 30 and 40. On the other hand, if it exceeds 50 μm, it tends to be difficult to ensure conduction between the connection terminals 32 and 42.

  Next, the circuit connection material 50 is placed on the surface of the first circuit member 30 where the connection terminals 32 are formed.

  Then, the circuit connection material is pressurized in the directions of arrows A and B in FIG. 5A to temporarily connect the circuit connection material 50 to the first circuit member 30 (FIG. 5B). Although the pressure at this time will not be restrict | limited especially if it is a range which does not damage a circuit member, Generally it is preferable to set it as 0.1-30.0 MPa. Moreover, you may pressurize, heating, and let heating temperature be the temperature which the circuit connection material 50 does not harden | cure substantially. In general, the heating temperature is preferably 50 to 190 ° C. These heating and pressurization are preferably performed in the range of 0.5 to 120 seconds.

  Here, the circuit connection material 50 may have a single-layer structure or a multilayer structure in which a plurality of layers are stacked. A circuit connection material having a multilayer structure can be produced by laminating a plurality of layers having different types of adhesive components and conductive particles or different contents thereof. For example, the circuit connection material may include a conductive particle-containing layer containing conductive particles and a conductive particle-free layer that does not contain conductive particles provided on one surface of the conductive particle-containing layer.

  FIG. 6 is a schematic cross-sectional view showing a circuit connecting material having a two-layer structure supported by a support. The circuit connection material 70 includes a conductive particle containing layer 70a containing conductive particles and a conductive particle non-containing layer 70b containing no conductive particles. Support bodies 60a and 60b are provided on both outermost surfaces of the circuit connection material 70, respectively. In the circuit connecting material 70, the conductive particle-containing layer 70a is formed on one surface of the support 60a, and the conductive particle-free layer 70b is formed on one surface of the support 60b. It can be manufactured by laminating using a laminator or the like. When using the circuit connecting material 70, the supports 60a and 60b are appropriately peeled off.

  According to the circuit connection material 70, when the IC chip is connected to the substrate by COG mounting or COF mounting, the number of conductive particles captured between the metal bumps of the IC chip and the substrate is sufficiently large. Good electrical connectivity.

  As shown in FIG. 5A, when the cross-sectional area of one connection terminal 42 is smaller than that of the other (for example, when a gold bump of an IC chip having a small cross-sectional area is connected to the ITO electrode), the connection terminal It is preferable to arrange the circuit connection material 70 so that the conductive particle non-containing layer 70 b comes into contact with the layer 32. When the circuit connection material 70 is arranged in this way, the conductive particles 10 are arranged in the vicinity of the connection terminals 32 of the first circuit member 30. For this reason, even if the adhesive component flows as the connection terminal 42 is inserted into the adhesive component 20, the movement of the conductive particles 10 is restricted by the adjacent connection terminal 32. Therefore, the number of conductive particles captured between the connection terminals 32 and 42 can be sufficiently increased.

  Next, as shown in FIG. 5C, the second circuit member 40 is placed on the circuit connection material 50 so that the connection terminal 42 faces the first circuit member 30. Then, while heating the circuit connecting material 50, the whole is pressurized in the directions of arrows A and B in FIG. As a result, the circuit connecting material 50 is cured, and the bonding portion 50a is formed, so that the circuit member connecting structure 100 as shown in FIG. 1 can be obtained.

  The heating temperature at this time is a temperature at which the circuit connecting material 50 can be cured. The heating temperature is preferably 60 to 180 ° C, more preferably 70 to 170 ° C, and still more preferably 80 to 160 ° C. If the heating temperature is less than 60 ° C, the curing rate tends to be slow, and if it exceeds 180 ° C, unwanted side reactions tend to proceed. The heating time is preferably 0.1 to 180 seconds, more preferably 0.5 to 180 seconds, and still more preferably 1 to 180 seconds.

  Further, the pressure load at this time is 50 MPa or less with respect to the electrode area of the IC chip. When pressure is applied at such a pressure, destruction of the circuit member and the like are prevented. The pressure load is preferably 15 to 40 MPa and more preferably 20 to 35 MPa with respect to the electrode area of the IC chip.

  In addition, although the process of connecting by heating and pressing was described here, the connection conditions can be appropriately selected depending on the application to be used, the adhesive composition, and the circuit member. For example, when an adhesive component of the circuit connection material 50 is used that is cured by light, the circuit connection material 50 may be appropriately irradiated with actinic rays or energy rays. Examples of the active light include ultraviolet light, visible light, and infrared light. Examples of energy rays include electron beams, X-rays, γ rays, and microwaves.

The load at the time of connection described above is a pressing force calculated from the following formula according to the electrode area of the IC chip.
Applied pressure = (IC chip electrode area) x (Target pressure)
The target pressure is 50 MPa or less, preferably 15 to 40 MPa, more preferably 20 to 35 MPa.

  FIG. 7 is a plan view showing an example of an electrode of an IC chip. The IC chip 90 shown in FIG. 7 includes a chip body 82 and electrodes 80 arranged in a staggered manner. In this case, the electrode area of the IC chip is obtained by summing the areas of the electrodes 80.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment. The present invention can be variously modified without departing from the gist thereof.

  EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited to these Examples.

Example 1
50 g of phenoxy resin synthesized from bisphenol A type epoxy resin (trade name “YL-980”, manufactured by Japan Epoxy Resin Co., Ltd.) and 9,9′-bis (4-hydroxyphenyl) fluorene was used in toluene with a mass ratio of 50:50. (Boiling point 110.6 ° C., SP value 8.90) and ethyl acetate (boiling point 77.1 ° C., SP value 9.10) were dissolved in a mixed solvent to prepare a solution having a solid content of 40% by mass. In this solution, bisphenol A type liquid epoxy resin (epoxy equivalent: 185, product name “YL-980”, manufactured by Japan Epoxy Resin Co., Ltd.) is mixed with a phenoxy resin: bisphenol A type liquid epoxy resin in a mass ratio of 50: It was blended to be 50. In this compounded liquid, conductive particles are mixed and dispersed at 15% by volume with respect to the total volume of the resin component (total volume of the phenoxy resin and the bisphenol A type epoxy resin), and further, an aromatic sulfonium salt is added as a latent curing agent. 0.0g was added and the adhesive composition containing liquid 1 was prepared. The conductive particles are plastic particles having a particle size of 3.0 μm (suspension polymerization using benzoyl peroxide as a polymerization initiator by changing the mixing ratio of tetramethylolmethanetetraacrylate, divinylbenzene and styrene monomer). Particles having a particle size of 3.0 μm obtained by classification) electroless nickel plating and outermost layer palladium plating. No. 1 was used, and the trade name “Sun-Aid SI-60” manufactured by Sanshin Chemical Industry Co., Ltd. was used as the aromatic sulfonium salt.

Here, the conductive particle No. 1 was measured using a H-100 microhardness meter manufactured by Fischer Instruments Co., Ltd. As a result, the compression elastic modulus at 30% compression deformation of the particle diameter of the particles was 400 kgf / mm ² .

  The obtained adhesive composition-containing liquid 1 was applied to a 50 μm-thick polyethylene terephthalate (PET) film (hereinafter, referred to as “PET film 1” hereinafter) having a surface treated on one side. After coating using a “precision coating machine” manufactured by Yasui Seiki Co., Ltd., it was dried with hot air at 70 ° C. for 5 minutes to obtain a resin film 1 having a thickness of 6 μm supported by the PET film 1.

  Next, 60 g of bisphenol F-type phenoxy resin (product name “FX-316”, manufactured by Tohto Kasei Co., Ltd.) was added to toluene (boiling point 110.6 ° C., SP value 8.90) having a mass ratio of 50:50 and ethyl acetate ( It was dissolved in a mixed solvent having a boiling point of 77.1 ° C. and an SP value of 9.10) to prepare a solution having a solid content of 60% by mass. In this solution, bisphenol A type liquid epoxy resin (epoxy equivalent: 185, manufactured by Japan Epoxy Resin Co., Ltd., trade name “YL-980”) is mixed with bisphenol F type phenoxy resin: bisphenol A type liquid epoxy resin in a solid mass ratio. Was 60:40. To this blended liquid, 4.8 g of aromatic sulfonium salt was further added as a latent curing agent to prepare an adhesive composition-containing liquid 2. In addition, as an aromatic sulfonium salt, the product name "Sun-Aid SI-60" by Sanshin Chemical Industry Co., Ltd. was used.

  The obtained adhesive composition-containing liquid 2 was applied to a 50 μm-thick polyethylene terephthalate (PET) film (the PET film used here is hereinafter referred to as “PET film 2”) having a surface treated on one side. After application using a “precision coating machine” manufactured by Yasui Seiki Co., Ltd., it was dried with hot air at 70 ° C. for 5 minutes to obtain a resin film 2 having a thickness of 14 μm supported by the PET film 2.

  Then, the resin film 1 and the resin film 2 are bonded to each other using a laminator (manufactured by MCK Co., Ltd., “Laminator”), and a two-layer structure (a conductive particle-containing layer and a conductive particle-free layer) as shown in FIG. An adhesive film for connecting circuit members was obtained.

(Example 2)
An adhesive film for connecting circuit members was obtained in the same manner as in Example 1 except that the resin film 1 was replaced with the resin film 3 described below.

(Manufacture of resin film 3)
50 g of phenoxy resin synthesized from bisphenol A type epoxy resin (trade name “YL-980”, manufactured by Japan Epoxy Resin Co., Ltd.) and 9,9′-bis (4-hydroxyphenyl) fluorene was used in toluene with a mass ratio of 50:50. (Boiling point 110.6 ° C., SP value 8.90) and ethyl acetate (boiling point 77.1 ° C., SP value 9.10) were dissolved in a mixed solvent to prepare a solution having a solid content of 40% by mass. In this solution, bisphenol A type liquid epoxy resin (epoxy equivalent: 185, product name “YL-980”, manufactured by Japan Epoxy Resin Co., Ltd.) is mixed with a phenoxy resin: bisphenol A type liquid epoxy resin in a mass ratio of 50: It was blended to be 50. In this compounded liquid, conductive particles are mixed and dispersed at 15% by volume with respect to the total volume of the resin component (total volume of the phenoxy resin and the bisphenol A type epoxy resin), and further, an aromatic sulfonium salt is added as a latent curing agent. 0.0 g was added to prepare an adhesive composition-containing liquid 3. The conductive particles are plastic particles having a particle size of 3.0 μm (suspension polymerization using benzoyl peroxide as a polymerization initiator by changing the mixing ratio of tetramethylolmethanetetraacrylate, divinylbenzene and styrene monomer). Particles having a particle size of 3.0 μm obtained by classification) electroless nickel plating and outermost layer palladium plating. 2 was used as the aromatic sulfonium salt, trade name “Sun-Aid SI-60” manufactured by Sanshin Chemical Industry Co., Ltd.

Here, the conductive particle No. 2 was measured using a H-100 microhardness meter manufactured by Fischer Instruments Co., Ltd. As a result, the compression modulus at 30% compression deformation of the particle diameter of the particles was 200 kgf / mm ² .

  The obtained adhesive composition-containing liquid 3 was applied to the PET film 1 using a coating apparatus (manufactured by Yasui Seiki Co., Ltd., “Precision Coating Machine”), and then dried with hot air at 70 ° C. for 5 minutes. Thus, a resin film 3 having a thickness of 6 μm supported by the PET film 1 was obtained.

(Comparative Example 1)
An adhesive film for connecting circuit members was obtained in the same manner as in Example 1 except that the resin film 1 was replaced with the resin film 4 described below.

(Manufacture of resin film 4)
50 g of phenoxy resin synthesized from bisphenol A type epoxy resin (trade name “YL-980”, manufactured by Japan Epoxy Resin Co., Ltd.) and 9,9′-bis (4-hydroxyphenyl) fluorene was used in toluene with a mass ratio of 50:50. (Boiling point 110.6 ° C., SP value 8.90) and ethyl acetate (boiling point 77.1 ° C., SP value 9.10) were dissolved in a mixed solvent to prepare a solution having a solid content of 40% by mass. In this solution, bisphenol A type liquid epoxy resin (epoxy equivalent: 185, product name “YL-980”, manufactured by Japan Epoxy Resin Co., Ltd.) is mixed with a phenoxy resin: bisphenol A type liquid epoxy resin in a mass ratio of 50: It was blended to be 50. In this compounded liquid, conductive particles are mixed and dispersed at 15% by volume with respect to the total volume of the resin component (total volume of the phenoxy resin and the bisphenol A type epoxy resin), and further, an aromatic sulfonium salt is added as a latent curing agent. 0.0g was added and the adhesive composition containing liquid 4 was prepared. The conductive particles are plastic particles having a particle size of 3.0 μm (suspension polymerization using benzoyl peroxide as a polymerization initiator by changing the mixing ratio of tetramethylolmethanetetraacrylate, divinylbenzene and styrene monomer). Particles having a particle size of 3.0 μm obtained by classification) electroless nickel plating and outermost layer gold plating. 3 was used as the aromatic sulfonium salt, trade name “Sun-Aid SI-60” manufactured by Sanshin Chemical Industry Co., Ltd.

Here, the conductive particle No. 3 was measured using a H-100 microhardness meter manufactured by Fisher Instruments Co., Ltd. As a result, the compression elastic modulus at 30% compression deformation of the particle diameter of the particles was 400 kgf / mm ² .

  The obtained adhesive composition-containing liquid 4 was applied to the PET film 1 using a coating apparatus (manufactured by Yasui Seiki Co., Ltd., “Precision Coating Machine”), and then dried with hot air at 70 ° C. for 5 minutes. Thus, a resin film 4 having a thickness of 6 μm supported by the PET film 1 was obtained.

(Comparative Example 2)
An adhesive film for connecting circuit members was obtained in the same manner as in Example 1 except that the resin film 1 was replaced with the resin film 5 described below.

(Manufacture of resin film 5)
50 g of phenoxy resin synthesized from bisphenol A type epoxy resin (trade name “YL-980”, manufactured by Japan Epoxy Resin Co., Ltd.) and 9,9′-bis (4-hydroxyphenyl) fluorene was used in toluene with a mass ratio of 50:50. (Boiling point 110.6 ° C., SP value 8.90) and ethyl acetate (boiling point 77.1 ° C., SP value 9.10) were dissolved in a mixed solvent to prepare a solution having a solid content of 40% by mass. In this solution, bisphenol A type liquid epoxy resin (epoxy equivalent: 185, product name “YL-980”, manufactured by Japan Epoxy Resin Co., Ltd.) is mixed with a phenoxy resin: bisphenol A type liquid epoxy resin in a mass ratio of 50: It was blended to be 50. In this compounded liquid, conductive particles are mixed and dispersed at 15% by volume with respect to the total volume of the resin component (total volume of the phenoxy resin and the bisphenol A type epoxy resin), and further, an aromatic sulfonium salt is added as a latent curing agent. 0.0g was added and the adhesive composition containing liquid 5 was prepared. The conductive particles are plastic particles having a particle size of 3.0 μm (suspension polymerization using benzoyl peroxide as a polymerization initiator by changing the mixing ratio of tetramethylolmethanetetraacrylate, divinylbenzene and styrene monomer). Particles having a particle size of 3.0 μm obtained by classification) electroless nickel plating and outermost layer palladium plating. 4 was used as the aromatic sulfonium salt, “San-Aid SI-60” manufactured by Sanshin Chemical Industry Co., Ltd.

Here, the conductive particle No. 4 was measured using a H-100 microhardness meter manufactured by Fischer Instruments Co., Ltd. As a result, the compression modulus at 30% compression deformation of the particle diameter of the particles was 650 kgf / mm ² .

  The obtained adhesive composition-containing liquid 5 was applied to the PET film 1 using a coating apparatus (manufactured by Yasui Seiki Co., Ltd., “Precision Coating Machine”), and then dried with hot air at 70 ° C. for 5 minutes. Thus, a resin film 5 having a thickness of 6 μm supported by the PET film 1 was obtained.

  Using the obtained adhesive films for connecting circuit members of Examples 1 and 2 and Comparative Examples 1 and 2, the connection structure of the circuit members using a crimping apparatus (trade name: FC-1200, manufactured by Toray Engineering Co., Ltd.) Produced. Specifically, first, the PET film on the conductive particle-containing layer side of the circuit member connecting adhesive film was peeled off to expose the surface of the conductive particle-containing layer. Next, an ITO film was formed by vapor deposition on a glass having a thickness of 0.5 mm to obtain an ITO substrate (surface resistance <20Ω / □). Next, while pressing the surface of the conductive film-containing layer of the circuit member connecting adhesive film face-to-face with the surface of the ITO film, heating and pressurizing in the laminating direction under conditions of 70 ° C., 0.5 MPa, 2 seconds, An adhesive film for connecting circuit members was temporarily fixed to the ITO substrate. Thereafter, the other PET film was peeled off from the circuit member connecting adhesive film. Next, an IC chip provided with two rows (staggered arrangement) of gold bumps having a bump area of 15 μm × 100 μm, a pitch of 30 μm, and a height of 15 μm was placed on the adhesive film for connecting circuit members. An adhesive film on which an IC chip is placed is sandwiched between quartz glass and a pressure head, and heated and pressed under the conditions of low pressure mounting conditions and standard conditions, thereby connecting the ITO substrate and the IC chip to form a circuit member connection structure. Produced. Specific conditions of low pressure mounting conditions and standard conditions are shown below.

[Low pressure mounting conditions]
Heating temperature: 170 ° C
Pressurized pressure: 30 MPa relative to the electrode area of the IC chip
Heating and pressing time: 5 seconds

[Standard conditions]
Heating temperature: 170 ° C
Pressurized pressure: 80 MPa relative to the electrode area of the IC chip
Heating and pressing time: 5 seconds

<Measurement of connection resistance>
About the above-mentioned circuit member connection structure, the electric resistance value of the connection part is initially used, and after being held for 500 hours in a high-temperature and high-humidity tank (85 ° C. and 85% RH environment), a four-terminal measurement method is used Measurement was performed using a resistance measuring machine (trade name: Digital Multimeter, manufactured by Advantest Corporation). The results are shown in Table 1.

  From the above, the circuit connection materials of Examples 1 and 2 have good electrical connectivity and long-term reliability of electrical characteristics between the connected circuit members even when the circuit members are connected at a low pressure. I confirmed that I could keep it.

  DESCRIPTION OF SYMBOLS 1 ... Nuclear particle, 1a ... Nuclear body (plastic particle), 1b ... Conductive layer (metal layer), 2A ... Insulating particle (insulating coating body), 2B ... Insulating layer (insulating coating body) 10, 10A, 10B ... Conductive particles, 20 ... Adhesive component, 30 ... First circuit member, 40 ... Second circuit member, 31, 41 ... Circuit board, 32, 42 ... Connection terminal, 50, 70 ... Circuit connection material (circuit member) Adhesive film for connection), 60, 60a, 60b ... support, 100 ... connection structure.

Claims (6)

The first circuit electrode having the first circuit electrode and the second circuit member having the second circuit electrode are interposed between the first circuit electrode and the second circuit electrode by pressurization. A circuit connection material for electrical connection,
At least one of the first circuit member and the second circuit member is an IC chip,
The load in the pressurization is 50 MPa or less with respect to the electrode area of the IC chip,
The circuit connecting material contains conductive particles and an adhesive component;
The conductive particles have a metal layer on the surface of the plastic particles, and the outermost layer of the metal layer is palladium;
The circuit connection material whose compression elastic modulus at the time of 30% compression deformation of the particle diameter in the said electrically-conductive particle is 100-500 kgf / mm < ² >.   The circuit connection material of Claim 1 which contains a film formation material, an epoxy resin, and a latent hardener as an adhesive agent component in the said circuit connection material. A first circuit member having a first circuit electrode and at least one of which is an IC chip, and a second circuit member having a second circuit electrode,
The first circuit electrode and the second circuit electrode are arranged to face each other,
The circuit connection material according to claim 1 or 2 is interposed between the first circuit electrode and the second circuit electrode arranged to face each other, and a load of 50 MPa or less is applied to the electrode area of the IC chip. A circuit member connection structure in which pressure is applied under conditions to electrically connect the first circuit electrode and the second circuit electrode.   At least one of the first circuit electrode and the second circuit electrode is gold, silver, tin, platinum group metal, aluminum, titanium, molybdenum, chromium, indium-tin oxide (ITO), and indium-zinc The circuit member connection structure according to claim 3, comprising a circuit electrode made of at least one selected from the group consisting of oxides (IZO).   The at least one of the first circuit member and the second circuit member is coated or adhered with at least one selected from the group consisting of silicon nitride, a silicone compound, and a polyimide resin. The circuit member connection structure according to 1. A first circuit member having a first circuit electrode and at least one of which is an IC chip, and a second circuit member having a second circuit electrode,
The first circuit electrode and the second circuit electrode are arranged to face each other,
The circuit connection material according to claim 1 or 2 is interposed between the first circuit electrode and the second circuit electrode arranged to face each other, and a load of 50 MPa or less is applied to the electrode area of the IC chip. A method for manufacturing a circuit member connection structure comprising a step of applying pressure under conditions to electrically connect the first circuit electrode and the second circuit electrode.

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