HK1206381B

HK1206381B - Anisotropic conductive film, connection method, and connected body

Info

Publication number: HK1206381B
Application number: HK15107085.4A
Authority: HK
Inventors: 深谷达朗; 伊藤将太
Original assignee: 迪睿合电子材料有限公司
Priority date: 2012-09-21
Filing date: 2013-09-13
Publication date: 2017-11-24

Description

Anisotropic conductive film, connection method, and bonded body

Technical Field

The invention relates to an anisotropic conductive film, a connection method and a bonded body.

Background

Conventionally, as a means for connecting electronic components to each other, a tape-shaped connecting material (for example, Anisotropic Conductive Film (ACF)) in which a curable resin in which Conductive particles are dispersed is applied to a release Film has been used.

The anisotropic conductive film is mainly used when terminals of a Flexible Printed Circuit (FPC) or an IC chip are connected to ito (indium Tin oxide) electrodes formed on a glass substrate of an LCD panel, and is used when various terminals are bonded and electrically connected to each other at the same time.

In recent years, in anisotropic conductive connection between electronic components using the anisotropic conductive film, an anisotropic conductive film using a cationic curing agent that can be cured at a low temperature and at a high speed is used in order to cope with the increase in density of a bonded body obtained by connection, the reduction in cost of connection, the suppression of warpage of a substrate or the like caused by high-temperature connection, and the like.

However, in the anisotropic conductive film using the cationic curing agent, there is a problem that the wiring of the electronic component is corroded by an acid generated when the cationic curing agent is used. In addition, there is a problem that the adhesiveness is insufficient.

It is known that a metal hydroxide or a metal oxide can be used as a connecting material for preventing corrosion of wiring (see, for example, paragraph [0040] of patent document 1). However, the mere addition of a metal hydroxide or a metal oxide to an anisotropic conductive film using a cationic curing agent cannot prevent the corrosion of the wiring. In addition, the adhesion is not sufficient.

Therefore, an anisotropic conductive film using a cationic curing agent, which satisfies the requirements for prevention of short circuit in an electronic component in a bonded body to be obtained in an anisotropic conductive film, excellent particle capture rate, low connection resistance, low-temperature curing and rapid curing, and further, corrosion prevention of wiring in the electronic component, and excellent adhesion, is desired; and a connection method using the anisotropic conductive film; and a joined body obtained by the joining method.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2011-

Disclosure of Invention

Problems to be solved by the invention

The present invention has been made to solve the above-described various problems of the related art and to achieve the following object. That is, an object of the present invention is to provide an anisotropic conductive film using a cationic curing agent, which satisfies the requirements for prevention of short circuit in an electronic component in a bonded body to be obtained in the anisotropic conductive film, excellent particle capture rate, and low connection resistance, can be cured at low temperature and rapidly, further prevents corrosion of wiring included in the electronic component, and has excellent adhesion; and a connection method using the anisotropic conductive film; and a bonded body obtained by the connecting method.

Means for solving the problems

The means for solving the above problems are as follows. That is to say that the first and second electrodes,

< 1 > an anisotropic conductive film for anisotropic conductive connection between a terminal of a first electronic component and a terminal of a second electronic component,

comprising: a conductive particle-containing layer containing conductive particles, a filler and a cationic curing agent, and

an insulating adhesive layer containing a cationic curing agent and no filler,

the conductive particles are at least one of metal particles and metal-coated resin particles,

the filler is at least one of a metal hydroxide and a metal oxide.

< 2 > the anisotropic conductive film according to the above < 1 >, wherein at least any one of the metal hydroxide and the metal oxide is at least any one of aluminum hydroxide, magnesium hydroxide and aluminum oxide.

< 3 > the anisotropic conductive film according to any one of the above < 1 > to < 2 >, wherein the conductive particle-containing layer contains a film-forming resin and a curable resin.

< 4 > the anisotropic conductive film according to the above < 3 >, wherein the content of the filler in the conductive particle-containing layer is 0.20 to 90 parts by mass based on 100 parts by mass of the total amount of the film-forming resin, the curable resin and the cationic curing agent.

< 5 > the anisotropic conductive film according to any one of the above < 1 > -4 >, wherein the filler is in a particle form, and an average particle diameter of the filler is 0.5 μm to 3.5 μm.

< 6 > the anisotropic conductive film according to any one of the above < 1 > -5 >, wherein the filler is in the form of non-spherical particles.

< 7 > a connecting method for anisotropically connecting a terminal of a first electronic component and a terminal of a second electronic component, comprising:

a first disposing step of disposing the anisotropic conductive film described in any one of the above-mentioned items < 1 > -6 > on a terminal of the second electronic component;

a second arrangement step of arranging the first electronic component on the anisotropic conductive film so that a terminal of the first electronic component is in contact with the anisotropic conductive film;

and a heating and pressing step of heating and pressing the first electronic component by a heating and pressing member.

< 8 > a joined body, characterized by being obtained by the joining method as described in < 7 > above.

Effects of the invention

The present invention can solve the above-described problems of the prior art and achieve the above-described objects, and can provide an anisotropic conductive film using a cationic curing agent which satisfies the requirements for an anisotropic conductive film, such as prevention of short circuit in an electronic component in a bonded body to be obtained, excellent particle capture rate, low connection resistance, low-temperature curing and rapid curing, further prevents corrosion of wiring lines of the electronic component, and has excellent adhesion; and a connection method using the anisotropic conductive film; and a bonded body obtained by the connecting method.

Detailed Description

(Anisotropic conductive film)

The anisotropic conductive film of the present invention has at least a conductive particle-containing layer and an insulating adhesive layer, and further has another layer as necessary.

The anisotropic conductive film is an anisotropic conductive film for anisotropically and electrically connecting a terminal of the first electronic component and a terminal of the second electronic component.

The structure of the anisotropic conductive film is not particularly limited and may be appropriately selected depending on the purpose, but a two-layer structure composed of the conductive particle-containing layer and the insulating adhesive layer is preferable.

< first electronic component and second electronic component >

The first electronic component and the second electronic component are not particularly limited as long as they are electronic components to be subjected to anisotropic conductive connection using the anisotropic conductive film and having terminals, and may be appropriately selected according to the purpose, and examples thereof include: glass substrates, flexible substrates, rigid substrates, ic (integrated circuit) chips, tab (tape automated bonding), liquid crystal panels, and the like. Examples of the glass substrate include: an Al wiring glass substrate, an ITO wiring glass substrate, and the like. Examples of the IC chip include an IC chip for controlling a liquid crystal screen in a Flat Panel Display (FPD).

< layer containing conductive particles >

The conductive particle-containing layer contains at least conductive particles, a filler and a cationic curing agent, preferably contains a film-forming resin and a curable resin, and further contains other components as required.

Conductive particles-

The conductive particles are not particularly limited as long as they are at least one of metal particles and metal-coated resin particles, and may be appropriately selected according to the purpose.

The metal particles are not particularly limited and may be appropriately selected according to the purpose, and examples thereof include: nickel, cobalt, silver, copper, gold, palladium, and the like. These metals may be used alone in 1 kind, or may be used in combination in 2 or more kinds.

Among them, nickel, silver, and copper are preferable. These metal particles may have gold or palladium applied to the surface thereof in order to prevent surface oxidation. Further, particles having a metal protrusion or an insulating film of an organic substance applied on the surface thereof can be used.

The metal-coated resin particles are not particularly limited as long as the surface of the resin particles is coated with a metal, and may be appropriately selected according to the purpose, and examples thereof include particles in which the surface of the resin particles is coated with at least any one metal of nickel, copper, gold, and palladium. Further, particles having a metal protrusion or an insulating film of an organic substance applied on the surface thereof can be used.

The method for coating the resin particles with a metal is not particularly limited, and may be appropriately selected according to the purpose, and examples thereof include an electroless plating method, a sputtering method, and the like.

The material of the resin particles is not particularly limited, and may be appropriately selected according to the purpose, and examples thereof include: styrene-divinylbenzene copolymer, benzoguanamine resin, crosslinked polystyrene resin, acrylic resin, styrene-silica composite resin, and the like.

The conductive particles may have conductivity at the time of anisotropic conductive connection. For example, even particles in which an insulating film is applied to the surface of metal particles function as the conductive particles as long as the particles are deformed to expose the metal particles during anisotropic conductive connection.

The content of the conductive particles in the conductive particle-containing layer is not particularly limited, and may be appropriately adjusted depending on the wiring pitch, the connection area, and the like of the circuit component.

Fillers-

The filler is not particularly limited as long as it is at least one of a metal hydroxide and a metal oxide, and may be appropriately selected according to the purpose.

The metal hydroxide and the metal oxide are used for preventing corrosion of wiring, improving adhesion, and improving insulation properties.

Examples of the metal hydroxide include: aluminum hydroxide, magnesium hydroxide, calcium hydroxide, and the like.

Examples of the metal oxide include: alumina, silica, magnesia, antimony oxide, tin oxide, titanium oxide, manganese oxide, zirconium oxide, and the like.

Among these, at least one of aluminum hydroxide, magnesium hydroxide and aluminum oxide is preferable, and at least one of aluminum hydroxide and magnesium hydroxide is more preferable, from the viewpoint of corrosion resistance and adhesion.

Further, it is known that corrosion of metal hydroxides and metal oxides is prevented and adhesion is improved as described in, for example, Japanese patent application laid-open Nos. 2004-523661 and 2011-111556.

The filler is preferably in the form of particles.

Examples of the particulate filler include: spherical fillers, non-spherical fillers, and the like. Among these, in view of insulation properties, a non-spherical filler is preferable, and an amorphous filler is more preferable.

The non-spherical shape is a shape other than the spherical shape.

The amorphous form means that: the non-spherical shape includes not only 1 type of shape but also a mixture of shapes having various forms. Examples of the various forms include projections and depressions, corners, and protrusions.

The average particle diameter of the filler when the filler is in a particle form is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 0.5 to 3.5 μm, and more preferably 0.5 to 2.0 μm. When the average particle diameter is within the more preferable range, it is advantageous in that the insulating property, the particle capturing ratio, and the connection resistance are more excellent.

The average particle diameter is an arithmetic average of particle diameters arbitrarily measured for 10 fillers.

When the filler is non-spherical, the maximum length of the particles is defined as the particle diameter.

The particle size can be determined by observation with a scanning electron microscope, measurement with a particle size distribution meter, or the like.

The ratio (a/B) of the average particle diameter (a) of the filler to the average particle diameter (B) of the conductive particles when the filler is in a particle form is not particularly limited and may be appropriately selected according to the purpose, but is preferably 1/10 to 2/3, and more preferably 1/10 to 1/2. When the ratio is within the more preferable range, the insulating property, the particle capturing ratio, and the connection resistance are more excellent.

The method for measuring the average particle diameter of the conductive particles is the same as the method for measuring the average particle diameter of the filler.

The content of the filler is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 0.20 to 90 parts by mass, and more preferably 4.0 to 30 parts by mass, based on 100 parts by mass of the total amount of the film-forming resin, the curable resin, and the cationic curing agent. When the content is within the more preferable range, it is advantageous in that the low-temperature curing and the rapid curing are maintained, and the corrosion resistance, the adhesion, and the insulation property are further excellent.

Cationic curing agents

The cationic curing agent is not particularly limited as long as it is a curing agent that generates cationic species, and may be appropriately selected according to the purpose, and examples thereof includeSalts and the like.

As described aboveSalts, for example: sulfonium salts, iodonium salts, and the like.

Examples of the sulfonium salt include triarylsulfonium salts.

As described aboveThe counter anion in the salt is not particularly limited and may be appropriately selected according to the purpose, and examples thereof include: SbF₆ ^－、AsF₆ ^－、PF₆ ^－、BF₄ ^－、CH₃SO₃ ^－、CF₃SO₃ ^－And the like.

The cationic curing agent may be a commercially available product. Examples of the commercially available products include: adeka optomer SP-172 (manufactured by ADEKA K.K.), Adeka optomer SP-170 (manufactured by ADEKA K.K.), Adeka optomer SP-152 (manufactured by ADEKA K.K.), Adeka optomer SP-150 (manufactured by ADEKA K.K.), San-Aid SI-60L (manufactured by Sanxin chemical industries, Ltd.), San-Aid SI-80L (manufactured by Sanxin chemical industries, Ltd.), San-Aid SI-100L (manufactured by Sanxin chemical industries, Ltd.), San-Aid SI-150L (manufactured by Sanxin chemical industries, Ltd.), CPI-100P (manufactured by Sanxin Apro) and CPI-101A (manufactured by Sanapro Apro Co., Ltd.), CPI-200K (manufactured by Sanapro Apro Co., Ltd.), and BASF 250 (manufactured by BASF K.K.).

The content of the cationic curing agent in the conductive particle-containing layer is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 10 to 50 parts by mass, and more preferably 20 to 40 parts by mass, based on 100 parts by mass of the total amount of the film-forming resin and the curable resin.

Film-forming resin-

The film-forming resin is not particularly limited and may be appropriately selected according to the purpose, and examples thereof include: phenoxy resins, unsaturated polyester resins, saturated polyester resins, polyurethane resins, butadiene resins, polyimide resins, polyamide resins, polyolefin resins, and the like. The film-forming resin may be used alone in 1 kind, or may be used in combination in 2 or more kinds. Among them, phenoxy resins are preferred from the viewpoint of film-forming properties, processability, and connection reliability.

Examples of the phenoxy resin include resins synthesized from bisphenol a and epichlorohydrin.

As the phenoxy resin, synthetic resins can be suitably used, and commercially available products can also be used.

The content of the film-forming resin in the conductive particle-containing layer is not particularly limited and may be appropriately selected according to the purpose.

A curable resin-

The curable resin is not particularly limited as long as it is a resin that is cured by the action of the cationic curing agent, and may be appropriately selected according to the purpose, and examples thereof include epoxy resins and the like.

The epoxy resin is not particularly limited and may be appropriately selected according to the purpose, and examples thereof include: bisphenol a type epoxy resins, bisphenol F type epoxy resins, novolac type epoxy resins, modified epoxy resins thereof, and the like.

The content of the curable resin in the conductive particle-containing layer is not particularly limited and may be appropriately selected according to the purpose.

Other ingredients-

The other component is not particularly limited and may be appropriately selected according to the purpose, and examples thereof include a silane coupling agent.

The silane coupling agent is not particularly limited and may be appropriately selected according to the purpose, and examples thereof include: epoxy silane coupling agents, acrylic silane coupling agents, thiol silane coupling agents, amine silane coupling agents, and the like.

The content of the silane coupling agent in the conductive particle-containing layer is not particularly limited and may be appropriately selected according to the purpose.

The average thickness of the conductive particle-containing layer is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 3 to 30 μm, more preferably 4 to 20 μm, and particularly preferably 4 to 10 μm.

The method for producing the conductive particle-containing layer is not particularly limited and may be appropriately selected according to the purpose, and examples thereof include a method in which a blend containing the conductive particles, the filler, and the cationic curing agent, preferably containing the film-forming resin and the curable resin, is mixed so as to be uniform, and the mixed blend is applied to a polyethylene terephthalate (PET) film subjected to a peeling treatment.

< insulating adhesive layer >

The insulating adhesive layer contains at least a cationic curing agent, does not contain a filler, and further contains other components as required.

Cationic curing agents

The cationic curing agent is not particularly limited and may be appropriately selected according to the purpose, and examples thereof include the cationic curing agents exemplified in the description of the conductive particle-containing layer. The same applies to the preferred aspects.

The content of the cationic curing agent in the insulating adhesive layer is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 10 to 50 parts by mass, and more preferably 20 to 40 parts by mass, based on 100 parts by mass of the total amount of the film-forming resin and the curable resin.

Fillers-

The filler is not particularly limited as long as it is at least one of a metal hydroxide and a metal oxide, and may be appropriately selected according to the purpose, and examples thereof include the fillers exemplified in the description of the conductive particle-containing layer.

Other ingredients-

The other components are not particularly limited and may be appropriately selected according to the purpose, and examples thereof include: film-forming resins, curable resins, silane coupling agents, and the like.

The film-forming resin, the curable resin, and the silane coupling agent are not particularly limited and may be appropriately selected according to the purpose, and examples thereof include the film-forming resin, the curable resin, and the silane coupling agent exemplified in the description of the conductive particle-containing layer. The same applies to the preferred aspects.

The average thickness of the insulating adhesive layer is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 3 to 30 μm, more preferably 5 to 20 μm, and particularly preferably 7 to 15 μm.

The method for producing the insulating adhesive layer is not particularly limited, and may be appropriately selected according to the purpose, and examples thereof include a method in which a blend containing the cationic curing agent, and further, if necessary, the film-forming resin and the curable resin is uniformly mixed, and the mixed blend is applied to a polyethylene terephthalate (PET) film subjected to a peeling treatment.

The method for producing the anisotropic conductive film is not particularly limited and may be appropriately selected depending on the purpose, and examples thereof include a method in which a conductive particle-containing layer produced by the above-described method for producing a conductive particle-containing layer and an insulating adhesive layer produced by the above-described method for producing an insulating adhesive layer are laminated using a roll laminator or the like.

(connection method and bonded body)

The connecting method of the present invention includes at least a first arranging step, a second arranging step, and a heating and pressing step, and further includes other steps as necessary.

The connection method is a method of anisotropically electrically connecting terminals of a first electronic component and terminals of a second electronic component.

The joined body of the present invention is obtained by the joining method of the present invention.

The first electronic component and the second electronic component are not particularly limited and may be appropriately selected according to the purpose, and for example, the first electronic component and the second electronic component exemplified in the description of the anisotropic conductive film of the present invention are exemplified.

< first arranging step >

The first disposing step is not particularly limited as long as the anisotropic conductive film of the present invention is disposed on the terminals of the second electronic component, and may be appropriately selected according to the purpose.

In the first disposing step, the anisotropic conductive film is disposed on the terminals of the second electronic component so that the terminals are in contact with the conductive particle-containing layer of the anisotropic conductive film, for example.

< second positioning step >

The second disposing step is not particularly limited as long as the first electronic component is disposed on the anisotropic conductive film such that the terminal of the first electronic component is in contact with the anisotropic conductive film, and may be appropriately selected according to the purpose.

< Process of heating and extruding >

The heating and pressing step is not particularly limited as long as the electronic component is heated and pressed by the heating and pressing member, and may be appropriately selected according to the purpose.

Examples of the heating and pressing member include a pressing member having a heating mechanism. Examples of the pressing member having the heating mechanism include a heating tool.

The heating temperature is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 120 to 200 ℃.

The pressure for the extrusion is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 0.1 to 100 MPa.

The time for the heating and pressing is not particularly limited and may be appropriately selected according to the purpose, but is preferably 0.5 to 120 seconds.

Examples

The following examples of the present invention are described, but the present invention is not limited to these examples at all.

(production example)

< preparation of Filler >

The aluminum hydroxides used in the following examples and comparative examples are produced by appropriately adjusting the production method of aluminum hydroxide described in paragraphs [0019] to [0023] of Japanese patent application laid-open No. 2005-162606.

The magnesium hydroxide, the aluminum oxide, and the magnesium oxide are produced by the same method as the method for producing aluminum hydroxide.

(example 1)

< production of Anisotropic conductive film >

Preparation of the layer containing conductive particles

A phenoxy resin (PKHH, manufactured by mitsubishi chemical corporation) 25 parts by mass, an epoxy resin (EP1001, manufactured by mitsubishi chemical corporation) 10 parts by mass, a cationic curing agent (SI-60L, manufactured by mitsubishi chemical corporation) 10 parts by mass, a silane coupling agent (a-187, manufactured by mitsubishi chemical corporation) 2 parts by mass, conductive particles (AUL704, manufactured by waterlogging chemical corporation), metal resin particles having a Ni/Au plating film formed on the surface of acrylic resin particles, and an average particle diameter of 4.0 μm)30 parts by mass, and aluminum hydroxide (amorphous, average particle diameter of 0.7 μm)0.1 part by mass were mixed uniformly using a stirring device (revolution mixer, debubbling tera, manufactured by THINKY). The mixed blend was applied to the peeled PET film so that the average thickness after drying became 10 μm, thereby producing a conductive particle-containing layer.

Production of an insulating adhesive layer

25 parts by mass of a phenoxy resin (PKHH, manufactured by mitsubishi chemical corporation), 10 parts by mass of an epoxy resin (EP1001, manufactured by mitsubishi chemical corporation), 10 parts by mass of a cationic curing agent (SI-60L, manufactured by mitsunobu chemical corporation, sulfonium salt type cationic curing agent), and 2 parts by mass of a silane coupling agent (a-187, manufactured by mitsunobu high-tech) were uniformly mixed by using a stirring device (a rotating and revolving mixer, debubbling teralang, manufactured by THINKY). The mixed blend was applied to a PET film subjected to a peeling treatment so that the average thickness after drying became 10 μm, to prepare an insulating adhesive layer.

The conductive particle-containing layer and the insulating adhesive layer obtained above were laminated at a roll temperature of 45 ℃ using a roll laminator, to obtain an anisotropic conductive film.

< production of joined body and evaluation of joined body >

A joined body was produced by the following method, and the following evaluations were performed. The results are shown in Table 2-1.

The anisotropic conductive film obtained above is disposed on a second electronic component so that the conductive particle-containing layer is in contact with the second electronic component. Next, a first electronic component is disposed on the insulating adhesive layer of the anisotropic conductive film. Next, the first electronic component was heated and pressed by a heater at 170 ℃, 60MPa, and 5 seconds using a teflon (registered trademark) sheet having an average thickness of 50 μm as a cushion material.

[ evaluation of Corrosion resistance ]

IC chip for test and glass substrate

As the first electronic component, an IC chip for test (size 1.8 mm. times.20 mm, thickness 0.5mm, gold plating bump size 30 μm. times.85 μm, bump height 15 μm) was used.

As the second electronic component, a glass substrate having a thickness of 0.7mm and formed with Al comb-shaped wiring was used.

Evaluation-

DC 5V was applied to the Al comb-shaped wiring of the obtained joined body for 12 hours. The group of Al comb-shaped wires 12 after application was observed with a metal microscope and evaluated according to the following evaluation criteria.

[ evaluation standards ]

O: no corrosion was observed.

And (delta): 1-4 corrosion sites were observed.

X: more than 5 corrosion sites were observed.

Evaluation of adhesion

IC chip for test and glass substrate

As the second electronic component, a glass substrate having a thickness of 0.5mm on the entire surface of which an ITO film is formed was used.

Evaluation-

The degree of protrusion of the anisotropic conductive film from the glass substrate after the pressure cooker boiling test (PCT) was visually observed, and evaluation was performed according to the following evaluation criteria. In addition, PCT was performed at 121 ℃ under 2atm for 5 hours.

[ evaluation standards ]

O: no doming was observed.

And (delta): with respect to the crimping area, a swelling of more than 0% and less than 10% was observed.

X: a bulge of 10% or more was observed with respect to the crimping area.

[ insulation evaluation ]

IC chip for test and glass substrate

As the first electronic component, an IC chip for test (size 1.5 mm. times.300 mm, thickness 0.5mm, inter-bump spacing of gold plated bumps 10 μm, bump height 15 μm) was used.

As the second electronic component, a glass substrate having a thickness of 0.5mm and formed with a comb-shaped ITO wiring pattern was used.

Evaluation-

The number of short circuits between the bumps at arbitrary 16 positions (160 in total) per 1 group was calculated for each group of ITO comb-shaped wiring 10 by the 2-terminal method, and evaluated according to the following evaluation criteria. The resistance value measured by the 2-terminal method was 10⁸When Ω or less, it is judged as a short circuit.

[ evaluation standards ]

O: there is no short circuit.

And (delta): there are 1 or 2 shorts.

X: there are more than 3 shorts.

[ evaluation of particle Capture Rate ]

IC chip for test and glass substrate

A glass substrate having a thickness of 0.7mm and formed with ITO wiring was used as the second electronic component.

Evaluation-

The particle capture rate was determined by the following method and evaluated.

The number of conductive particles (the number of particles before connection) positioned on the bump (terminal) of the first electronic component before connection of the first electronic component and the second electronic component is calculated by the following formula (1).

Number of particles before connection (number of particles per mm) of conductive particles in the conductive particle-containing layer²) × area of terminal (mm)²)··(1)

The number of conductive particles (the number of particles after connection) located on the terminal after connection was measured by counting with a metal microscope. Then, the particle capture rate of the conductive particles was calculated by the following formula (2). Then, evaluation was performed according to the following evaluation criteria.

Particle capture rate (%) (number of particles after connection/number of particles before connection) × 100 · (2)

[ evaluation standards ]

O: the particle capture rate is more than 20%

And (delta): the particle capture rate is more than 17% and less than 20%

X: the particle capture rate is less than 17%

< evaluation of connection resistance >

IC chip for test and glass substrate

As the second electronic component, a glass substrate having a thickness of 0.7mm on which ITO wiring is formed was used.

Evaluation-

The initial resistance value of the obtained joined body was measured and evaluated by the following method.

The connection resistance when a current of 1mA was passed was measured by a 4-terminal method using a Digital multimeter (product number: Digital Multi-meter 7555, manufactured by Yokogawa electric Co., Ltd.). The obtained resistance values were evaluated according to the following evaluation criteria.

[ evaluation standards ]

O: initial resistance value of less than 1 omega

And (delta): an initial resistance value of 1 omega or more and less than 3 omega

X: initial resistance value of 3 omega or more

(examples 2 to 6)

An anisotropic conductive film and a bonded body were produced in the same manner as in example 1, except that the amount of aluminum hydroxide (filler) to be blended in the production of the conductive particle-containing layer in example 1 was changed to the amount shown in table 1 below.

The obtained joined body was evaluated in the same manner as in example 1. The results are shown in Table 2-1.

[ Table 1]

	Example 2	Example 3	Example 4	Example 5	Example 6
						Blending amount (parts by mass) of filler	0.5	2.0	10	20	40

(example 7)

An anisotropic conductive film and a joined body were produced in the same manner as in example 4, except that in example 4, magnesium hydroxide (amorphous, average particle size 0.7 μm) was used instead of aluminum hydroxide.

(example 8)

An anisotropic conductive film and a joined body were produced in the same manner as in example 4, except that in example 4, aluminum hydroxide was replaced with aluminum oxide (amorphous, average particle size: 0.7 μm).

The obtained joined body was evaluated in the same manner as in example 1. The results are shown in Table 2-2.

(example 9)

An anisotropic conductive film and a joined body were produced in the same manner as in example 4, except that in example 4, spherical aluminum hydroxide (average particle size: 0.7 μm) was used instead of amorphous aluminum hydroxide.

(example 10)

An anisotropic conductive film and a joined body were produced in the same manner as in example 4, except that in example 4, aluminum hydroxide having an average particle size of 0.7 μm was replaced with aluminum hydroxide having an average particle size of 0.5 μm (amorphous).

(example 11)

An anisotropic conductive film and a joined body were produced in the same manner as in example 4, except that in example 4, aluminum hydroxide having an average particle size of 0.7 μm was replaced with aluminum hydroxide having an average particle size of 2.0 μm (amorphous).

(example 12)

An anisotropic conductive film and a joined body were produced in the same manner as in example 4, except that in example 4, aluminum hydroxide having an average particle size of 0.7 μm was replaced with aluminum hydroxide having an average particle size of 3.5 μm (amorphous).

(example 13)

An anisotropic conductive film and a joined body were produced in the same manner as in example 4, except that in example 4, magnesium oxide (amorphous, average particle size 0.7 μm) was used instead of aluminum hydroxide.

(example 14)

An anisotropic conductive film and a joined body were produced in the same manner as in example 4, except that in example 4, 10 parts by mass of aluminum hydroxide was replaced by 5 parts by mass of aluminum hydroxide (amorphous, average particle size of 0.7 μm) and 5 parts by mass of aluminum oxide (amorphous, average particle size of 0.7 μm).

Comparative example 1

An anisotropic conductive film and a joined body were produced in the same manner as in example 1, except that 10 parts by mass of aluminum hydroxide (amorphous, average particle diameter 0.7 μm) was added in the production of the insulating adhesive layer in example 4.

The obtained joined body was evaluated in the same manner as in example 1. The results are shown in tables 2 to 3.

Comparative example 2

An anisotropic conductive film and a joined body were produced in the same manner as in example 1, except that in example 1, aluminum hydroxide was not contained in the conductive particle-containing layer, and that 10 parts by mass of aluminum hydroxide (amorphous, average particle diameter of 0.7 μm) was added in the production of the insulating adhesive layer.

Comparative example 3

An anisotropic conductive film and a bonded body were produced in the same manner as in example 1, except that in example 1, aluminum hydroxide was not contained in the conductive particle-containing layer.

Comparative example 4

25 parts by mass of a phenoxy resin (PKHH, manufactured by Bakushi chemical Co., Ltd.), 10 parts by mass of an epoxy resin (EP1001, manufactured by Mitsubishi chemical Co., Ltd.), 10 parts by mass of a cationic curing agent (SI-60L, manufactured by Mitsubishi chemical Co., Ltd., sulfonium salt type cationic curing agent), 2 parts by mass of a silane coupling agent (A-187, manufactured by Mitsubishi chemical corporation), 30 parts by mass of conductive particles (AUL704, manufactured by waterlogging chemical Co., Ltd.), and 10 parts by mass of aluminum hydroxide (amorphous, average particle diameter of 0.7 μm) were uniformly mixed by using a stirring apparatus (autorotation mixer, debubbling teran, manufactured by INKY Co., Ltd.). The blend was applied to the PET subjected to the peeling treatment so that the average thickness after drying became 20 μm, thereby producing an anisotropic conductive film.

Using the obtained anisotropic conductive film, a bonded body was produced in the same manner as in example 1.

The results of the above examples and comparative examples are summarized in tables 2-1 to 2-3 below.

The content of the filler is the content of the filler based on 100 parts by mass of the total amount of the phenoxy resin, the epoxy resin, and the cationic curing agent in each layer.

[ Table 2-1]

[ tables 2-2]

[ tables 2 to 3]

In examples 1 to 14, only the conductive particle-containing layer contained the filler (at least either of the metal hydroxide and the metal oxide), and therefore, corrosion of the wiring was suppressed, and the corrosion resistance was good. Further, the adhesive property was excellent, and the insulation property, the particle capturing ratio and the connection resistance were also good.

In particular, when the content of the filler in the conductive particle-containing layer is 4.0 to 30 parts by mass with respect to 100 parts by mass of the total amount of the film-forming resin, the curable resin, and the cationic curing agent, more excellent results in corrosion resistance and adhesion can be obtained (for example, examples 3 and 4).

In addition, in the case of the filler is aluminum hydroxide or magnesium hydroxide among metal hydroxides, the results of more excellent corrosion resistance and adhesion can be obtained (for example, examples 4 and 7).

When the filler is amorphous, the result of having more excellent insulation than the case of a spherical shape can be obtained (for example, examples 4 and 9).

When the average particle diameter of the filler is 0.5 to 2.0 μm, the results of more excellent insulation, particle capturing ratio and connection resistance can be obtained (for example, examples 4, 10 and 11).

On the other hand, when the filler is contained not only in the conductive particle-containing layer but also in the insulating adhesive layer, the insulating property and the particle capturing rate are insufficient (comparative example 1).

When only the insulating adhesive layer contains the filler, both the corrosion resistance and the adhesion are reduced as compared with comparative example 1 (comparative example 2).

When the filler is not contained in any of the conductive particle-containing layer and the insulating adhesive layer, the corrosion resistance, adhesion, and insulation properties are insufficient (comparative example 3).

When the anisotropic conductive film had a 1-layer structure including only the conductive particle-containing layer and the filler was contained in the conductive particle-containing layer, the corrosion resistance, adhesion, insulation, and particle capture rate were insufficient (comparative example 4).

Industrial applicability of the invention

The anisotropic conductive film of the present invention is excellent in corrosion resistance and adhesion, and therefore can be suitably used for producing a bonded assembly which is cured at low temperature and cured rapidly by using a cationic curing agent.

Claims

1. An anisotropic conductive film for anisotropically and electrically connecting a terminal of a first electronic component and a terminal of a second electronic component,

an insulating adhesive layer containing a cationic curing agent and no filler,

the filler is at least one of a metal hydroxide and a metal oxide.

2. The acf of claim 1, wherein at least any one of the metal hydroxide and the metal oxide is at least any one of aluminum hydroxide, magnesium hydroxide, and aluminum oxide.

3. The anisotropic conductive film according to claim 1, wherein the conductive particle-containing layer contains a film-forming resin and a curable resin.

4. The anisotropic conductive film according to claim 3, wherein the content of the filler in the conductive particle-containing layer is 0.20 to 90 parts by mass with respect to 100 parts by mass of the total amount of the film-forming resin, the curable resin, and the cationic curing agent.

5. The anisotropic conductive film according to claim 1, wherein the filler is in a particle form, and an average particle diameter of the filler is 0.5 to 3.5 μm.

6. The acf of claim 1 wherein the filler is in the form of non-spherical particles.

7. A connection method for anisotropically electrically connecting a terminal of a first electronic component and a terminal of a second electronic component, comprising:

a first disposing step of disposing the anisotropic conductive film according to any one of claims 1 to 6 on a terminal of the second electronic component;

8. A joined body obtained by the joining method according to claim 7.