TWI681694B - Anisotropic conductive film and connecting method - Google Patents

Abstract

The present invention is an anisotropic conductive film having: a conductive particle-containing layer containing conductive particles, a thermosetting resin and a curing agent; and a thermoplastic layer containing an acid component.

Description

Anisotropic conductive film and its connection method

The invention relates to an anisotropic conductive film and a connection method thereof.

Conventionally, as a means of connecting an electronic component to a substrate, a strip-shaped connecting material (for example, anisotropic conductive film (ACF, Anisotropic Conductive Film)).

For example, the anisotropic conductive film is used for connection (FOB, Flex on Board) of a thin film flip-chip package (COF, Chip on Film) and a rigid substrate (such as a printed circuit board (PWB, Printed Wiring Board)).

In order to improve the solderability of integrated circuit (IC, Integrated Circuit) chips, capacitors and other components, the rigid substrate is provided with an anti-rust agent called Organic Solderability Preservative (OSP) Anti-rust treatment. As for this organic solderability protection, for example, imidazole-based organic solderability protection and the like.

However, the substrate after the rust prevention treatment has a problem that the adhesion of the anisotropic conductive film is reduced.

Therefore, in order to make the connection of the substrate after the anti-rust treatment have a stable connection reliability, it has been proposed that a circuit connection material contains a hardener that generates free radicals, a radically polymerizable substance, a phosphate ester, and conductive particles, and After deducting the conductive particles, when the whole circuit connecting material is 100 parts by weight, the proportion of phosphate ester is 0.5 weight of the whole circuit connecting material The range of parts by weight to 2.5 parts by weight (for example, refer to Patent Document 1).

However, in the proposed technology, although the insulation between adjacent terminals is excellent, the long-term conductivity between the connection terminals is not sufficient.

[Prior Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2009-277769

The present invention solves the above-mentioned conventional problems to achieve the following objects as a problem. That is, an object of the present invention is to provide an anisotropic conductive film and a combination using the anisotropic conductive film, which can provide insulation between adjacent terminals even when it is connected to a rust-prevented substrate Excellent long-term conductivity with connection terminals.

The means for solving the aforementioned problems are as follows. which is,

<1> An anisotropic conductive film comprising: a conductive particle-containing layer containing conductive particles, a thermosetting resin and a curing agent; and a thermoplastic layer containing an acid component.

<2> The anisotropic conductive film according to <1>, wherein the acid component is a phosphate compound.

<3> The anisotropic conductive film according to any one of <1> to <2>, wherein the conductive particle-containing layer has a melt viscosity greater than that of the thermoplastic layer.

<4> A connection method, which is a connection method for connecting the terminals of the first circuit element and the terminals of the second circuit element, including: a first configuration process, on the terminals of the first circuit element, the configuration is as in item 1 To the anisotropic conductive film according to any one of 3, the thermoplastic layer in the anisotropic conductive film is in contact with the terminal of the first circuit element; the second configuration process is on the anisotropic conductive film , Disposing the second circuit element; heating and pressing process, heating and pressurizing the second circuit element by the heating and pressing element; and, applying anti-rust treatment to the terminals of the first circuit element with an anti-rust agent.

According to the present invention, it is possible to solve the above-mentioned conventional problems and achieve the foregoing object, and it is possible to provide an anisotropic conductive film and a combination using the anisotropic conductive film even when connected to a substrate after rust prevention treatment Next, the insulation between adjacent terminals and the long-term conductivity between the connection terminals can also be made excellent.

1‧‧‧ First circuit element

1A‧‧‧Substrate

1B‧‧‧terminal

1C‧‧‧Antirust agent

2‧‧‧Anisotropic conductive film

2A‧‧‧thermoplastic layer

2B‧‧‧Conducting particle containing layer

2C‧‧‧conductive particles

3‧‧‧ Second circuit element

3A‧‧‧Substrate

3B‧‧‧Terminal

[Fig. 1A] Fig. 1A is a schematic cross-sectional view (part 1) for explaining an example of the connection method of the present invention.

[FIG. 1B] is a schematic cross-sectional view (No. 2) for explaining an example of the connection method of the present invention.

[FIG. 1C] is a schematic cross-sectional view (No. 3) for explaining an example of the connection method of the present invention.

[Fig. 1D] is a schematic cross-sectional view (No. 4) for explaining an example of the connection method of the present invention.

[FIG. 1E] is a schematic cross-sectional view (part 5) for explaining an example of the connection method of the present invention.

(Anisotropic conductive film)

The anisotropic conductive film of the present invention contains at least a conductive particle-containing layer and a thermoplastic layer, and further contains other components as necessary.

<Conductive particle-containing layer>

The conductive particle-containing layer contains at least conductive particles, a thermosetting resin, and a curing agent, and further contains other components as necessary.

<<conductive particles>>

The conductive particles are not particularly limited, and can be appropriately selected according to the purpose, for example, for example, metal particles, metal-coated resin particles, and the like.

The metal particles are not particularly limited, and can be appropriately selected according to the purpose, for example, nickel, cobalt, silver, copper, gold, palladium, tin, etc. Among these, one kind may be used alone, or two or more kinds may be used in combination.

Among them, nickel, silver and copper are preferred. For the purpose of preventing oxidation of the surface of these metal particles, gold and palladium may be applied to the surface. Furthermore, it is also possible to use an object in which an insulating coating of metal protrusions or organic substances is applied to the surface of the metal particles.

The metal-coated resin particles are not particularly limited as long as the surfaces of the resin particles are coated with metal, and can be appropriately selected according to the purpose. For example, for example, the surface of the resin particles contains at least nickel, silver, Particles coated with any metal of tin, copper, gold and palladium, etc. Furthermore, it is also possible to use an object in which an insulating coating of metal protrusions or organic substances is applied to the surface of the metal particles. Considering the case of low resistance connection, the surface of the resin particles is coated with silver Is better.

The method of coating the metal with the resin particles is not particularly limited, and can be appropriately selected according to the purpose, for example, electroless plating method, sputtering method, etc.

The material of the resin particles is not particularly limited, and can be appropriately selected according to the purpose, for example, for example, styrene-divinylbenzene copolymer, benzoguanamine resin, bridged polystyrene resin, acrylic resin, benzene Ethylene-silica composite resin, etc.

This conductive particle system has conductivity when an anisotropic conductive connection is made. For example, even if a particle is coated with an insulating film on the surface of the metal particle, it is the conductive particle as long as it can deform the particle and expose the metal particle during anisotropic conductive connection.

Although the average particle size of the conductive particles is not particularly limited and can be appropriately selected according to the purpose, it is preferably 1 μm to 50 μm, more preferably 2 μm to 25 μm, and most preferably 2 μm to 10 μm.

The average particle size is the average value of the particle size of any ten conductive particles.

This particle size can be measured by observing a scanning electron microscope, for example.

Although the content of the conductive particles in the conductive particle-containing layer is not particularly limited and can be appropriately selected according to the purpose, it is preferably 0.5% by weight to 10% by weight, more preferably 1% by weight to 5% by weight %.

<<Thermosetting resin>>

The thermosetting resin is not particularly limited, and can be appropriately selected according to the purpose, for example, epoxy resin, polymerizable acrylic compound and the like.

---Epoxy resin---

The epoxy resin is not particularly limited, and can be appropriately selected according to the purpose. For example, for example, bisphenol A epoxy resin, bisphenol F epoxy resin, phenol novolac epoxy resin, etc. Epoxy resin, alicyclic epoxy resin, etc. Among these, one kind may be used alone, or two or more kinds may be used in combination.

---Polymerizable acrylic compound---

The polymerizable acrylic compound is not particularly limited and can be appropriately selected according to the purpose. For example, for example, polyethylene glycol diacrylate, phosphate acrylate, 2-hydroxyethyl acrylate, acrylic acid 2- Hydroxypropyl ester, 4-hydroxybutyl acrylate, isobutyl acrylate, third butyl acrylate, isooctyl acrylate, bisphenoxyethanol fluorene diacrylate, 2-propenyl oxyethyl succinic acid, laurel acrylate Ester, stearyl acrylate, isobornyl acrylate, tricyclodecane dimethanol dimethacrylate, cyclohexyl acrylate, tris (2-hydroxyethyl) isocyanurate triacrylate, tetrahydrofuran acrylate Ester, phthalate diglycidyl ether acrylate, ethoxylated bisphenol A dimethacrylate, bisphenol A epoxy acrylate, urethane acrylate, epoxy acrylate, etc., and equivalent acrylic acid Methyl ester. Among these, one kind may be used alone, or two or more kinds may be used in combination.

Although the content of the thermosetting resin in the conductive particle-containing layer is not particularly limited and can be appropriately selected according to the purpose, it is preferably 20% by weight to 60% by weight, and more preferably 30% by weight to 50% weight%.

<<Hardener>>

The curing agent is not particularly limited, and can be appropriately selected according to the purpose. For example, for example, imidazoles, organic peroxides, anionic curing agents, and cationic curing agents.

Examples of the imidazoles include 2-ethyl-4-methylimidazole and the like.

As for the organic peroxide, for example, for example, lauryl peroxide, butyl peroxide, benzene peroxide, dilaurate peroxide, dibutyl peroxide, peroxydicarbonate, peroxide Oxybenzoyl oxide, etc.

Examples of the anionic hardener include organic amines.

The cationic hardener is, for example, samium salt, onium salt, aluminum chelating agent and the like.

Among them, from the viewpoint of excellent preservation stability, organic peroxides are preferred, and dilaurate peroxide is more preferred.

The combination of the thermosetting resin and the curing agent is not particularly limited and can be appropriately selected according to the purpose, but the combination of the epoxy resin and the cationic curing agent, the polymerizable acrylic compound and the organic peroxide The combination of substances is preferred.

Although the content of the hardener in the conductive particle-containing layer is not particularly limited and can be appropriately selected according to the purpose, it is preferably 1% by weight to 15% by weight, more preferably 2% by weight to 10% by weight .

<<Other Ingredients>>

Other components contained in the conductive particle-containing layer include, for example, film-forming resins and fillers.

-Film forming resin-

The film-forming resin is not particularly limited and can be appropriately selected according to the purpose, for example, for example, phenoxy resin, unsaturated polyester resin, saturated polyester resin, urethane resin, butadiene Resin, polyimide resin, polyimide resin, polyolefin resin, etc. This film-forming resin may be used alone or in combination of two or more. Among these, phenoxy resins are preferred from the viewpoint of film formability, processability, and connection reliability.

The phenoxy resin is, for example, a resin synthesized by bisphenol A and epichlorohydrin.

As the phenoxy resin, an appropriately synthesized product may be used, or a commercially available product may be used.

The content of the film-forming resin in the conductive particle-containing layer is not particularly limited. Although it can be appropriately selected according to the purpose, it is preferably 20% by weight to 60% by weight, and more preferably 30% by weight to 50% by weight. %.

-Filler-

The filler is not particularly limited and can be appropriately selected according to the purpose, for example, alumina, silica, talc, mica, kaolin, zeolite, barium sulfate, calcium carbonate, and the like.

The content of the filler in the conductive particle-containing layer is not particularly limited. Although it can be appropriately selected according to the purpose, it is preferably 0.5% by weight to 15% by weight, and more preferably 1% by weight to 10% by weight. .

The conductive particle-containing layer preferably contains no acid component. The acid component is, for example, an acid component described below.

The average thickness of the conductive particle-containing layer is not particularly limited. Although it can be appropriately selected according to the purpose, it is preferably 10 μm to 50 μm, and more preferably 20 μm to 40 μm.

The average thickness here is the average value after measuring the thickness of any five positions of the conductive particle-containing layer.

<thermoplastic layer>

The thermoplastic layer system contains at least an acid component, and further contains other components as necessary.

The thermoplastic layer is a layer that exhibits plasticity by heat.

The thermoplastic layer may contain a compound having a reactive functional group such as an epoxy resin or a polymerizable acrylic compound, but at this time, it does not contain a hardener that hardens these compounds.

<<Acid Composition>>

The acid component is not particularly limited as long as it is acidic, and can be appropriately selected according to the purpose. As for the acidic group in the acid component, for example, for example, phosphate group, carboxyl group, sulfonate group and the like. Examples of the compound having an acidic group include, for example, (meth)acrylates having an acidic group.

The acid component may be rosin (rosin acid). The rosin produces acid by melting.

Among them, the phosphate compound system is preferred from the viewpoint of strong acidity and easy removal of the rust inhibitor. The phosphate ester compound is, for example, a phosphate ester acrylate.

The content of the acid component in the thermoplastic layer is not particularly limited. Although it can be appropriately selected according to the purpose, it is preferably 1% by weight to 10% by weight, and more preferably 2% by weight to 6% by weight. If the content is less than 1% by weight, the removal of the rust inhibitor will be insufficient; if the content exceeds 10% by weight, the composition of the acid component and the other components of the thermoplastic layer will become unbalanced.

<<Other Ingredients>>

As for other components in the thermoplastic layer, for example, for example, film-forming resins, other resins, and the like.

-Film forming resin-

The film-forming resin is not particularly limited, and can be appropriately selected according to the purpose, for example, the film-forming resin exemplified in the description of the conductive particle-containing layer. The preferred form is also the same.

The content of the film-forming resin in the thermoplastic layer is not particularly limited. Although it can be appropriately selected according to the purpose, it is preferably 0% by weight to 20% by weight, and more preferably 0% by weight to 10% by weight.

-Other resin-

The other resin is not particularly limited as long as it is a resin other than the film-forming resin, and can be appropriately selected according to the purpose, for example, epoxy resin, polymerizable acrylic compound and the like. Therefore, the system is generally used as a component of the anisotropic conductive film, and can also be used as the material of the thermoplastic layer in the anisotropic conductive film of the present invention. However, in the case where the thermoplastic layer contains a compound having these reactive functional groups, usually, the thermoplastic layer does not contain such compounds Hardener for hardening of objects.

The content of other resins in the thermoplastic layer is not particularly limited. Although it can be appropriately selected according to the purpose, it is preferably 60% by weight to 99% by weight, and more preferably 80% by weight to 97% by weight.

The average thickness of the thermoplastic layer is not particularly limited. Although it can be appropriately selected according to the purpose, it is preferably 1 μm to 10 μm, and more preferably 2 μm to 7 μm. If the average thickness is within a preferable range, it is beneficial to simplify the control of the fluidity of the thermoplastic layer, so that the thermoplastic layer is less likely to remain in the connecting portion after lamination.

The average thickness here is the average value after measuring the thickness of any five positions of the thermoplastic layer.

In terms of the melt viscosity of the conductive particle-containing layer, the melt viscosity of the conductive particle-containing layer is preferably greater than the melt viscosity of the thermoplastic layer from the viewpoint of easily excluding the thermoplastic layer from between the connection terminals. In terms of the ratio of the melt viscosity, from the viewpoint of easily excluding the thermoplastic layer from between the connection terminals, the melt viscosity of the conductive particle-containing layer is preferably more than 10 times the melt viscosity of the thermoplastic layer, more The best is 15~70 times, the best is 20~70 times.

The melt viscosity here is measured using, for example, a rheometer (manufactured by HAAKE Co., Ltd.). For example, to measure each layer. The temperature under the flow area is measured, and the result of setting the temperature at 85°C during the viscosity measurement is the melt viscosity.

(connection method)

The connection method of the present invention includes at least a first configuration process, a second configuration process, and a heat and pressure process, and includes other processes as necessary.

The connection method is to connect the terminal of the first circuit element to the terminal of the second circuit element connection method.

<First circuit element and second circuit element>

As far as the first circuit element and the second circuit element are concerned, as long as they have terminals and are the objects of the anisotropic conductive connection using the anisotropic conductive film, there is no particular limitation, and they can respond to the purpose Appropriate selection, for example, for example, a plastic substrate with terminals, a flexible hard board with terminals (FOB, Flex-on-Board), a flexible board with terminals to each other (FOF, Flex-on-Flex), etc.

The material of the terminal is not particularly limited, and can be appropriately selected according to the purpose. For example, for example, Cu, Au is plated with Cu, Ni, Au is plated with Cu, and Sn is plated with Cu.

The material and structure of the plastic substrate with the terminal are not particularly limited, and can be appropriately selected according to the purpose. For example, for example, a rigid substrate with a terminal and a flexible substrate with a terminal. The rigid substrate having the terminal is, for example, a glass epoxy substrate having copper wiring, and the like. As for the flexible substrate having this terminal, for example, for example, a polyimide substrate having copper wiring and the like.

The shape and size of the first circuit element and the second circuit element are not particularly limited, and can be appropriately selected according to the purpose.

The first circuit element and the second circuit element are the same circuit element, or may be different circuit elements.

The terminals of the first circuit element are subjected to anti-rust treatment with an anti-rust agent.

It is preferable that the terminal of the second circuit element is not subjected to anti-rust treatment with anti-rust agent.

The rust inhibitor is not particularly limited, and can be appropriately selected according to the purpose. This rust inhibitor is generally referred to as Organic Solderability Preservative (OSP).

This rust preventive system contains, for example, at least an imidazole compound, copper ions, and organic acids. Imidazole For compounds, for example, benzimidazole and the like. The benzimidazole may have a substituent.

The rust inhibitor is preferably water-soluble.

The method of the anti-rust treatment is not particularly limited, and can be appropriately selected according to the purpose, for example, for example, a method of immersing the circuit element to be treated in the anti-rust agent or diluting the anti-rust agent in an aqueous solution .

By performing this anti-rust treatment, the terminals and circuit parts on the circuit element are protected.

<First Configuration Process>

As far as the first arrangement process is concerned, as long as the process of disposing the anisotropic conductive film of the present invention on the terminals of the first circuit element, the thermoplastic layer is in contact with the terminals of the first circuit element, there is no particular limitation , Can be appropriately selected according to the purpose.

<Second configuration process>

As far as the second arrangement process is concerned, as long as the process of disposing the second circuit element on the anisotropic conductive film is not particularly limited, it can be appropriately selected according to the purpose.

<heating and pressing process>

The heating and pressing process is not particularly limited as long as it is a process of heating and pressing the second circuit element through the heating and pressing element, and can be appropriately selected according to the purpose. For example, the heating and pressing element can be heated and Pressure, etc.

The heating and pressurizing element is, for example, a pressing element having a heating mechanism. As for the pressurizing element having this heating mechanism, for example, for example, a heating tool or the like.

The heating temperature is not particularly limited, and although it can be appropriately selected according to the purpose, it is preferably 140°C to 200°C.

The pressurized pressure is not particularly limited. Although it can be appropriately selected according to the purpose, it is Preferably it is 0.1MPa-80MPa.

The heating and pressurizing time is not particularly limited, and can be appropriately selected according to the purpose, for example, for example, 0.5 seconds to 120 seconds.

Here, an example of the connection method of the present invention will be described using drawings.

1A to 1E are schematic cross-sectional views for explaining an example of the connection method of the present invention.

First, as shown in FIG. 1A, the first circuit element 1 is prepared. The first circuit element 1 has a base 1A and a terminal 1B on the base 1A. At the same time, the terminal 1B is subjected to an anti-rust treatment with an anti-rust agent 1C.

Furthermore, as shown in FIG. 1B, an anisotropic conductive film 2 is arranged on the first circuit element 1. The anisotropic conductive film 2 is formed by laminating a thermoplastic layer 2A and a conductive particle-containing layer 2B. At the same time, an anisotropic conductive film 2 is arranged on the first circuit element 1 so that the thermoplastic layer 2A is in contact with the terminal 1B of the first circuit element 1. At the same time, the conductive particle-containing layer 2B contains the conductive particles 2C. At this time, as shown in FIG. 1C, the acid component in the thermoplastic layer 2A removes the rust inhibitor 1C from the terminal 1B.

Furthermore, as shown in FIG. 1D, the second circuit element 3 is arranged on the conductive particle-containing layer 2B of the anisotropic conductive film 2. The second circuit element 3 has a base 3A and a terminal 3B located on the base 3A. On the conductive particle-containing layer 2B of the anisotropic conductive film 2, the second circuit element 3 is arranged so that the terminal 3B is in contact with the conductive particle-containing layer 2B.

Furthermore, as shown in FIG. 1E, the first circuit element 1 and the second circuit element 3 are connected by heating and pressurizing the second circuit element 3. At this time, since the rust inhibitor is not present on the terminal 1B, good connectivity can be obtained. At the same time, when the thermoplastic layer 2A is heated and pressurized, at least part of the thermoplastic layer 2A is squeezed out from between the terminal 1B and the terminal 3B, the acid component in the thermoplastic layer 2A will not deteriorate the terminal 1B or the terminal 3B (Eg corrosion, dissolution, electron migration, etc.).

Therefore, with the connection method of the present invention, even when connected to the substrate after the rust prevention treatment In this case, the insulation between adjacent terminals and the long-term conductivity between the connection terminals can also be made excellent.

Meanwhile, in the above description of FIGS. 1A to 1E, although FIG. 1C illustrates the state where the rust inhibitor is removed, the connection method of the present invention is not limited to this state. For example, in the first placement process, even if the rust inhibitor is not removed from the terminal, the rust inhibitor may be removed from the terminal during the heat and pressure process. The connection method of the present invention also includes such aspects.

【Example】

Hereinafter, although the embodiments of the present invention are described, the present invention is not limited to any of these embodiments.

(Example 1)

<Fabrication of anisotropic conductive film>

<<Production of the first floor>>

Bisphenol F type epoxy resin (manufactured by Mitsubishi Chemical Corporation, trade name: jER-4004P) 55 parts by mass, bifunctional acrylic monomer (manufactured by Shin Nakamura Chemical Industry Co., Ltd., trade name: A-200 ) 25 parts by mass, polyurethane acrylate (manufactured by Shin Nakamura Chemical Industry Co., Ltd., trade name: U-2PPA) 20 parts by mass and phosphate ester acrylate (manufactured by Nippon Kayaku Co., Ltd., trade name: PM-2) 4 parts by mass, uniformly mixed by a conventional method to prepare the composition for the first layer. The obtained composition was applied to a peeling polyester film, and dried with hot air at 70° C. for 3 minutes to prepare a first layer having an average thickness of 5 μm.

<<Production of the second layer>>

Phenoxy resin (manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd., trade name: YP50) 45 parts by mass, bifunctional acrylic monomer (manufactured by Shin Nakamura Chemical Industry Co., Ltd., trade name: A-200) 20 Mass parts, polyurethane acrylate (manufactured by Shin Nakamura Chemical Industry Co., Ltd., trade name: U-2PPA) 20 parts by mass, silica filler (made by Japan AEROSIL Co., Ltd., trade name: AerosilRY200, average particle diameter 5 μm) 5 parts by mass, dilaurate peroxide (manufactured by Nippon Oil Co., Ltd., trade name: PEROYL ^® L) 5 parts by mass and 3 parts by mass of nickel electroplating resin particles with an average particle diameter of 10 μm, uniformly mixed by a conventional method to prepare a second Layer composition. The obtained composition was applied to a peeling polyester film, and dried with hot air at 70° C. for 5 minutes to prepare a second layer having an average thickness of 30 μm.

The first layer and the second layer were laminated using a laminator to obtain an anisotropic conductive film with a two-layer structure.

(Example 2)

An anisotropic conductive film was produced in the same manner as in Example 1, except that in Example 1, the average thickness of the first layer was changed to 3 μm and the average thickness of the second layer was changed to 32 μm.

(Example 3)

An anisotropic conductive film was produced in the same manner as in Example 1, except that the composition of the first layer in Example 1 was changed to the composition shown in Table 1.

(Example 4)

Except that the composition of the first layer, the average thickness of the first layer, and the average thickness of the second layer in Example 1 were changed as shown in Table 1, in the same manner as in Example 1, the anisotropic conductive film was subjected to Make.

(Example 5)

An anisotropic conductive film was produced in the same manner as in Example 1, except that the composition of the first layer in Example 1 was changed as shown in Table 1.

(Example 6)

An anisotropic conductive film was produced in the same manner as in Example 1, except that the composition of the first layer in Example 1 was changed as shown in Table 1.

(Comparative example 1)

In addition to changing the composition of the first layer in Example 1 as shown in Table 1, it is the same as Example 1. Similarly, an anisotropic conductive film is produced.

(Comparative example 2)

Except that the composition of the first layer, the average thickness of the first layer, and the average thickness of the second layer in Example 1 were changed as shown in Table 1, in the same manner as in Example 1, the anisotropic conductive film was subjected to Make.

(Comparative example 3)

Phenoxy resin (manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd., trade name: YP50) 45 parts by mass, bifunctional acrylic monomer (manufactured by Shin Nakamura Chemical Industry Co., Ltd., trade name: A-200) 20 Mass parts, polyurethane acrylate (manufactured by Shin Nakamura Chemical Industry Co., Ltd., trade name: U-2PPA) 20 parts by mass, phosphate ester acrylate (manufactured by Nippon Pharmaceutical Co., Ltd., trade name: PM-2) 4 mass Parts, silicon dioxide filler (manufactured by Japan Aerosil Co., Ltd., trade name: AerosilRY200, average particle diameter 5 μm) 5 parts by mass, dilaurate peroxide (manufactured by Nippon Oil Co., Ltd., trade name: PEROYL ^® L) 5 3 parts by mass and 3 parts by mass of nickel plating resin particles having an average particle diameter of 10 μm were uniformly mixed by a conventional method to prepare a composition for the second layer. The obtained composition was applied to a peeling polyester film, and dried by hot air blowing at 70° C. for 5 minutes to produce an anisotropic conductive film having an average thickness of 35 μm.

<Production of joint body>

As the first circuit element, a printed circuit board (PWB) (200 μm P, Cu 35 μm t-with anti-corrosion treatment, FR-4 base material, base material for evaluation made by Dierehe Co., Ltd.) was used.

As the second circuit element, a thin film flip-chip package (COF) (200 µm P, Cu 8 µm t-Sn-plated, 38 µm t-S'perflex substrate, substrate for evaluation made by Dierich Co., Ltd.) was used.

Using the prepared anisotropic conductive film, the first circuit element and the second circuit element are connected.

At the same time, the first circuit element passed through the reflow furnace with a maximum temperature of 250°C three times.

First, cut the anisotropic conductive film to a width of 2.0 mm, make the first layer contact with the terminal of the first circuit element, attach it to the first circuit element, and then align the second circuit element on it, use Heat and press the tool (250μm t-silicone rubber, 2.0mm wide buffer material), and perform pressure bonding under the pressure bonding condition of 170℃-3MPa-5 seconds to complete the joined body.

<Measurement of melt viscosity>

The melt viscosity of the first layer and the second layer in Examples and Comparative Examples was measured using a rheometer (made by HAAKE Co., Ltd.). The measurement was carried out for each layer before the first layer and the second layer were laminated using a laminator. The temperature under the flow area is measured. The result of setting the temperature at 85°C during the viscosity measurement is shown in Table 1.

<THB evaluation>

THB evaluation was performed using the produced joint body. The bonded body was exposed to an environment of 60°C to 95% RH, and a DC voltage of 50V was applied for 250 hours. After the test, confirm whether there is insulation degradation caused by corrosion, electron migration, etc., and use the following evaluation criteria for evaluation. The results are shown in Table 1.

[Evaluation criteria]

○: Insulation resistance value 1.0x10 ⁹ Ω or more

△: Insulation resistance value above 1.0x10 ⁸ Ω and less than 1.0x10 ⁹ Ω

╳: Insulation resistance value is less than 1.0x10 ⁸ Ω

<Measurement of conduction resistance>

Regarding the manufactured joined body, the connection resistance at the time when a current of 1 mA was passed by the 4-terminal method was measured after 500 hours at 85°C and 85%RH at the initial stage, and the following evaluation criteria were used for evaluation. The results are shown in Table 1.

[Evaluation criteria]

○: Less than 0.3Ω

△: more than 0.3Ω and less than 0.6Ω

╳: Above 0.6Ω

表1所示配合量的單位係為質量份。

The unit system of the compounding amount shown in Table 1 is a mass part.

jER-4004P: Bisphenol F type epoxy resin, manufactured by Mitsubishi Chemical Corporation

YP-70: Bisphenol A/F epoxy-phenoxy resin, manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd.

YP-50: Bisphenol A epoxy-phenoxy resin, manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd.

A-200: Bifunctional acrylic monomer, manufactured by Shin Nakamura Chemical Industry Co., Ltd.

U-2PPA: polyurethane acrylate, manufactured by Shin Nakamura Chemical Industry Co., Ltd.

PM-2: Phosphate ester acrylate, manufactured by Nippon Kayaku Co., Ltd.

KE-604: Rosin, manufactured by Arakawa Chemical Industry Co., Ltd.

PEROYL ^® L: dilaurate peroxide, manufactured by NOF Corporation

AerosilRY200: silica filler, made by Japan AEROSIL Co., Ltd.

In Examples 1 to 6, the insulation between adjacent terminals and the long-term conductivity between the connection terminals are excellent.

In Comparative Example 1, although the first layer contains an acid component, since it contains a hardening component and a hardener, it is not a thermoplastic layer, so the insulation resistance is insufficient. This phenomenon is caused by the fact that the first layer is not squeezed out of the terminal after the joint is produced, and the acid component in the first layer causes damage to the terminal, causing electron migration to the terminal.

In Comparative Example 2, the conduction resistance was insufficient. This phenomenon is that although the first layer is a thermoplastic layer, the rust inhibitor on the terminal cannot be removed because it does not contain an acid component. As a result, the rust inhibitor reduces the connectivity between the terminals.

In Comparative Example 3, the insulation resistance was insufficient. This phenomenon is caused by the acid component damaging the terminal after the joint is produced, and the terminal undergoes electron migration.

[Industry availability]

The anisotropic conductive film of the present invention can be excellent in insulation between adjacent terminals and long-term conductivity between connecting terminals even when connected to a substrate after rust prevention treatment, so it can be applied to rust prevention treatment The connection between the rear substrate and other substrates.

1A‧‧‧Substrate

1B‧‧‧terminal

2B‧‧‧Conducting particle containing layer

2C‧‧‧conductive particles

3A‧‧‧Substrate

3B‧‧‧Terminal

Claims (5)

An anisotropic conductive film having: a conductive particle-containing layer containing conductive particles, a thermosetting resin and a hardener; and a thermoplastic layer containing an acid component; wherein the conductive particle containing layer The melt viscosity is greater than the melt viscosity of the thermoplastic layer. The anisotropic conductive film according to claim 1, wherein the acid component is a phosphate compound. A connection method is a connection method for connecting a terminal of a first circuit element and a terminal of a second circuit element, including: a first configuration process, on the terminal of the first circuit element, the configuration is as in items 1 to 2 The anisotropic conductive film according to any one of the items, the thermoplastic layer in the anisotropic conductive film is in contact with the terminal of the first circuit element; the second disposition process is to dispose the anisotropic conductive film on the anisotropic conductive film The second circuit element; a heating and pressing process, which heats and pressurizes the second circuit element by the heating and pressing element; and, applies a rust-proofing treatment to the terminal of the first circuit element with a rust inhibitor. A bonded body characterized in that the first circuit element and the second circuit element are anisotropically conductively connected by a cured product of the anisotropic conductive film according to any one of claims 1 to 2. A method of manufacturing a bonded body, characterized in that the first circuit element and the second circuit element are anisotropic by the cured product of the anisotropic conductive film as described in any one of claims 1 to 2. Conductive connection.

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