KR102420949B1 - Method for manufacturing connection structure, and anisotropic conductive adhesive film - Google Patents

Abstract

[PROBLEMS] To provide a method for producing a bonded structure and an anisotropic conductive adhesive film capable of obtaining excellent conduction resistance.
[Solution] A light irradiation step of irradiating ultraviolet rays to the anisotropic conductive film 20 in which a polymerizable compound and a photoinitiator are unevenly distributed at different locations, and a first circuit member and a second circuit member through the anisotropic conductive film 20 It has a thermocompression bonding process of thermocompression bonding. Since the photoinitiator in an anisotropic conductive film is thermocompression-bonded in the activated state, a wiring part can fully be hardened and the outstanding conduction resistance can be obtained. Further, since the polymerizable compound and the photopolymerization initiator in the anisotropic conductive film are unevenly distributed in different locations, the curing reaction at the time of UV irradiation is suppressed, and insufficient press-fitting due to line curing can be prevented.

Description

The manufacturing method of a bonded structure, and an anisotropic conductive adhesive film TECHNICAL FIELD

This invention relates to the manufacturing method of the bonded structure which electrically connects circuit members, and the anisotropic conductive film used for it.

Conventionally, in ACF (Anisotropic Conductive Film) connection of LCD (Liquid Crystal Display) panels, etc., the anisotropic conductive film is reacted and cured at low temperature by using ultraviolet irradiation to reduce the curvature of the LCD panel. It is reduced and suppressing display nonuniformity is performed (for example, refer patent document 1).

However, since the conventional ultraviolet irradiation is mainly performed from the lower part of the board|substrate, it is difficult to harden the wiring part with remarkably low light transmittance, and it is difficult to obtain the outstanding conduction resistance.

Japanese Patent Laid-Open No. 2007-45900

The present invention has been proposed in view of such a conventional situation, and provides a method for manufacturing a bonded structure and an anisotropic conductive adhesive film capable of obtaining excellent conduction resistance.

As a result of earnest examination, the present inventor irradiates ultraviolet rays to the anisotropic conductive film in which the polymerizable compound and the photoinitiator are localized at different locations to activate the photopolymerization initiator, then the first circuit member and the second circuit through the anisotropic conductive film It discovered that the hardening reaction of a wiring part was improved by crimping|bonding a member, and the outstanding conduction resistance was obtained.

That is, the method for manufacturing a bonded structure according to the present invention comprises a light irradiation step of irradiating ultraviolet rays to an anisotropic conductive film in which a polymerizable compound and a photopolymerization initiator are localized at different locations, and a first circuit member and a first circuit member through the anisotropic conductive film It has a thermocompression bonding process of thermocompression bonding two circuit members, It is characterized by the above-mentioned.

Moreover, the bonded structure which concerns on this invention is obtained by the manufacturing method mentioned above, It is characterized by the above-mentioned.

Moreover, the anisotropic conductive film which concerns on this invention has a 1st layer containing a polymeric compound and electroconductive particle, and it has a 2nd layer containing a photoinitiator and a non-polymerizable compound, It is characterized by the above-mentioned.

According to the present invention, since the anisotropic conductive film is irradiated with ultraviolet rays to activate the photopolymerization initiator and then thermocompression bonded, the wiring portion can be sufficiently hardened and excellent conduction resistance can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows the outline of a temporary attachment process.
It is sectional drawing which shows the outline of a light irradiation process.
It is sectional drawing which shows the outline of a mounting process.
It is sectional drawing which shows the outline of a thermocompression bonding process.
It is sectional drawing which shows the structural example of an anisotropic conductive film.
Fig. 6(A) is a cross-sectional view schematically showing the process of irradiating ultraviolet rays from above the anisotropic conductive film before mounting the IC, and Fig. 6(B) is a cross-sectional view schematically showing the process of thermocompression bonding the IC after ultraviolet irradiation. to be.
Fig. 7 is a cross-sectional view schematically showing a step of irradiating ultraviolet rays from above the IC after the IC is mounted.
Fig. 8 is a cross-sectional view schematically showing a step of irradiating ultraviolet rays from below the glass substrate after IC mounting.
Fig. 9(A) is a cross-sectional view schematically showing the step of irradiating ultraviolet rays from below the glass substrate before mounting the IC, and Fig. 9(B) is a cross-sectional view schematically showing the step of thermocompression bonding the IC after ultraviolet irradiation. .
It is sectional drawing which shows the structural example of the conventional anisotropic conductive film.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail in the following order, referring drawings.

1. Manufacturing method of bonded structure

2. Anisotropic conductive film

3. Examples

<1. Manufacturing method of bonded structure>

The manufacturing method of the bonded structure which concerns on this embodiment includes the light irradiation process of irradiating an ultraviolet-ray to the anisotropic conductive film in which the polymeric compound and the photoinitiator were unevenly distributed in different places, The 1st circuit member and the 2nd circuit via the anisotropic conductive film. It has a thermocompression bonding process of thermocompression bonding a member. Since the photoinitiator in an anisotropic conductive film is thermocompression-bonded in the activated state, a wiring part can fully be hardened and the outstanding conduction resistance can be obtained. In addition, since the polymerizable compound and the photopolymerization initiator in the anisotropic conductive film are unevenly distributed at different locations, the curing reaction during ultraviolet irradiation is suppressed, and insufficient press-fitting due to pre-curing can be prevented.

There is no restriction|limiting in particular for a 1st circuit member and a 2nd circuit member, According to the objective, it can select suitably. As a 1st circuit member, glass substrates, such as an LCD (Liquid Crystal Display) panel use, a plasma display panel (PDP) use, a printed wiring board (PWB), etc. are mentioned, for example. Further, as the second circuit member, for example, an IC (Integrated Circuit), a flexible substrate (FPC: Flexible Printed Circuits) such as a COF (Chip On Film), a tape carrier package (TCP) substrate, etc. are mentioned. have.

Moreover, the manufacturing method of the bonded structure which concerns on this embodiment has a temporary attachment process of temporarily attaching an anisotropic conductive film before a light irradiation process, and a mounting process of mounting a 2nd circuit member between a temporary attachment process and a thermocompression bonding process. 1 to 4 are cross-sectional views each showing the outline of a temporary bonding step, a light irradiation step, a mounting step, and a thermocompression bonding step in the method for manufacturing a bonded structure.

As shown in FIG. 1 , in the temporary attachment process, the anisotropic conductive film 20 is temporarily attached on the mounting portion in which the terminals of the first circuit member 10 are formed. Temporary attachment of the anisotropic conductive film 20 is performed by, for example, pressing at a low pressure with a crimping tool from above the base film, or by heat-pressing at a low pressure and short time at a temperature at which the binder exhibits fluidity but does not initiate curing. . In addition, after the temporary attachment of an anisotropic conductive film, a base film peels.

Next, as shown in FIG. 2 , in the light irradiation process, ultraviolet rays are irradiated to the anisotropic conductive film 20 temporarily attached on the first circuit member 10 . It is preferable that the irradiation direction of an ultraviolet-ray is from the side of the anisotropic conductive film 20 from a viewpoint of preventing the fall of the light transmittance by the 1st circuit member 10. Moreover, in the anisotropic conductive film 20, since a polymeric compound and a photoinitiator are unevenly distributed in different locations as mentioned later, the hardening reaction at the time of ultraviolet irradiation can be suppressed.

Next, as shown in FIG. 3 , in the mounting step, the second circuit member 30 is mounted on the mounting portion to which the anisotropic conductive film 20 is temporarily attached. At this time, alignment adjustment is performed so that the position of the terminal of the 2nd circuit member 30 and the terminal of the 1st circuit member 10 may match.

Next, as shown in FIG. 4 , in the thermocompression bonding process, the second circuit member 30 is thermally pressed for a predetermined pressure and a predetermined time by the crimping tool 40 heated to a predetermined temperature. (本) compressed. Here, although the time from completion of irradiation of ultraviolet-ray of a light irradiation process to thermocompression bonding differs with the kind of photoinitiator, it is preferable that it is 10 second or less. In addition, the predetermined temperature is the temperature of the anisotropic conductive film 20 at the time of crimping|compression-bonding, and it is preferable that they are 80 degreeC or more and 160 degrees C or less.

There is no restriction|limiting in particular as the crimping tool 40, It can select suitably according to the objective, and pressurization may be performed once using a pressurizing member larger than a press object, and also pressurizing using a pressurizing member smaller in area than a press object. You may divide it into several times and you may carry out. There is no restriction|limiting in particular as a front-end|tip shape of a crimping|compression-bonding tool, According to the objective, it can select suitably, For example, a planar shape, a curved-surface shape, etc. are mentioned. Further, when the tip shape is a curved shape, it is preferable to press along the curved shape.

In addition, a cushioning material may be interposed between the crimping tool 40 and the second circuit member 30 and thermocompression bonding may be performed. By interposing a cushioning material, while being able to reduce a pressurization nonuniformity, it can prevent that a crimping|compression-bonding tool is contaminated. The cushioning material includes a sheet-like elastic material or a calcined body, and for example, silicone rubber or polytetrafluoroethylene is used.

According to the manufacturing method of such a bonded structure, while the binder of the anisotropic conductive film 20 is fluidized, electroconductive particle is pinched between the terminals of the 1st circuit member 10 and the 2nd circuit member 30, and this state hardened in Thereby, the connection structure in which the 1st circuit member 10 and the 2nd circuit member 30 were electrically and mechanically connected is manufactured. In this embodiment, since the photoinitiator in the anisotropic conductive film is excited and thermocompression-bonded in the activated state, a wiring part can fully be hardened and the outstanding conduction resistance can be obtained. In addition, since the polymerizable compound and the photopolymerization initiator in the anisotropic conductive film are unevenly distributed in different locations, the curing reaction is suppressed during the light irradiation step, and insufficient press-fitting due to the line curing during the thermocompression bonding step can be prevented. In addition, as a light irradiation process, you may irradiate low-intensity ultraviolet-ray, and it is good also as normal environment, such as a fluorescent lamp. For this reason, the yellow room which cut off the ultraviolet-ray becomes unnecessary, there are few changes from the conventional line equipment of thermocompression bonding, and it is economical.

<2. Anisotropic Conductive Film>

In the anisotropic conductive film used in the above-described method for manufacturing the bonded structure, the polymerizable compound and the photopolymerization initiator are localized in different locations so that the curing reaction is suppressed during the light irradiation process. As a specific structure, the thing which separated and localized a photoinitiator and a polymeric compound to one surface and the other surface, respectively is mentioned. Hereinafter, the multilayer film which added the polymeric compound and the photoinitiator to the other layer is mentioned as an example and demonstrated.

It is sectional drawing which shows the structural example of an anisotropic conductive film. This anisotropic conductive film 20 has the 1st layer 21 containing a polymeric compound and electroconductive particle, and the 2nd layer 22 containing a photoinitiator and a non-polymerizable compound. By mix|blending a polymeric compound and a photoinitiator with the 1st layer 21 and the 2nd layer 22, respectively, the hardening reaction in the light irradiation process mentioned above can be suppressed.

Also, it is preferable to have a third layer 23 containing a non-polymerizable compound between the first layer 21 and the second layer 22 . It is preferable that the nonpolymerizable compound is a film-forming resin, and as one aspect, the 3rd layer 23 may contain only the film-forming resin. Since this 3rd layer 23 becomes a buffer layer of the polymeric compound of the 1st layer 21, and the photoinitiator of the 2nd layer 22, the hardening reaction in the above-mentioned light irradiation process can be suppressed further. . Since this 3rd layer 23 does not care about the uniformity of thickness, you may create it by application|coating or dispersion|spreading. In addition, the preferable film thickness of the sum total of the 1st layer 21, the 2nd layer 22, and the 3rd layer 23 is 4-50 micrometers.

As electroconductive particle, the well-known electroconductive particle currently used in an anisotropic conductive film can be used. For example, particles of various metals or metal alloys such as nickel, iron, copper, aluminum, tin, lead, chromium, cobalt, silver, gold, metal oxides, carbon, graphite, glass, ceramics, plastics, etc. Those in which a metal is coated on the surface, those in which an insulating thin film is further coated on the surface of these particles, and the like. When the surface of the resin particle is coated with a metal, the resin particle includes, for example, an epoxy resin, a phenol resin, an acrylic resin, an acrylonitrile/styrene (AS) resin, a benzoguanamine resin, a divinylbenzene-based resin, Particles, such as a styrenic resin, can be used. In addition, the electroconductive particle 10 may be mix|blended with not only the 1st layer 21 but the 2nd layer 22.

As an average particle diameter of electroconductive particle, it is 1-10 micrometers normally, More preferably, it is 2-6 micrometers. Moreover, content of electroconductive particle is 5-60 mass parts normally with respect to 100 mass parts of binder resin compositions, Preferably it is 10-50 mass parts.

The anisotropic conductive film will not be specifically limited if it is a photocurable type, For example, a cation hardening type, a radical hardening type, or these can be used together. Hereinafter, a cation-curable anisotropic conductive film is demonstrated.

The cation-curable first layer 21 and the second layer 22 contain, as a binder, a film-forming resin as a nonpolymerizable compound, a cationically polymerizable compound as a polymerizable compound, and a photocationic polymerization initiator as a photoinitiator.

Film-forming resin corresponds to high molecular weight resin with an average molecular weight of 10000 or more, for example, It is preferable that it is an average molecular weight of about 10000-80000 from a viewpoint of film formation. Various resins, such as a phenoxy resin, a polyester resin, a polyurethane resin, a polyester urethane resin, an acrylic resin, a polyimide resin, butyral resin, are mentioned as film-forming resin, These may be used individually, and two types You may use combining the above. Among these, it is preferable to use a phenoxy resin suitably from a viewpoint of a film formation state, connection reliability, etc. Content of film-forming resin is 30-80 mass parts normally with respect to 100 mass parts of binder resin compositions, Preferably it is 40-70 mass parts.

Examples of the cationically polymerizable compound include monofunctional epoxy compounds such as ethylene oxide, propylene oxide, butylene oxide, styrene oxide, phenyl glycidyl ether, and butyl glycidyl ether; Heterocyclic-containing epoxy resins, such as a bisphenol A epoxy resin, a bisphenol F-type epoxy resin, a phenol novolak-type epoxy resin, an alicyclic epoxy resin, triglycidyl isocyanate, and hydantoin epoxy; aliphatic epoxy resins such as hydrogenated bisphenol A epoxy resin, propylene glycol diglycidyl ether, and pentaerythritol-polyglycidyl ether; an epoxy resin obtained by reacting an aromatic, aliphatic or alicyclic carboxylic acid with epichlorohydrin; spiro ring-containing epoxy resin; a glycidyl ether type epoxy resin which is a reaction product of an o-allyl-phenol novolak compound and epichlorohydrin; a glycidyl ether type epoxy resin which is a reaction product of a diallyl bisphenol compound having an allyl group at the ortho position of each hydroxyl group of bisphenol A and epichlorohydrin; Diglycidyl ether-type epoxy resins of Schiff-based compounds, stilbene compounds, and azobenzene compounds; A fluorine-containing alicyclic or aromatic cyclic epoxy resin such as a reaction product of (1,1,1,3,3,3-hexafluoro-2-hydroxyisopropyl)cyclohexane and epichlorohydrin can be used. .

Since cationic polymerization accompanies a dark reaction, reaction progresses gradually even after completion|finish of light irradiation, and there exists a possibility of impairing the function as an adhesive film. Therefore, as a cationically polymerizable compound, it is preferable to use the bisphenol A epoxy resin or bisphenol F type epoxy resin in which a dark reaction does not generate|occur|produce comparatively easily.

When content of a cationically polymerizable compound is too small, conduction|electrical_connection reliability will become low, and since there exists a tendency for adhesive strength to become low when too large, Preferably it is 20-70 mass parts with respect to 100 mass parts of binder resin compositions, More preferably, 30 -60 parts by mass.

In the cationic polymerization initiator, the cationic species ring-opens the epoxy group at the end of the epoxy resin and self-crosslinks the epoxy resins. In this embodiment, a photocationic polymerization initiator may just be added, and a photocationic polymerization initiator and a thermal cationic polymerization initiator may be used together.

Examples of the photocationic polymerization initiator include triarylsulfonium salts, benzylsulfonium salts, triphenylsulfonium salts, diphenyl-4-thiophenoxyphenylsulfonium salts, triaryliodonium salts, diaryliodonium salts, and diphenyliodonium salts. , 4-methoxydiphenyl iodonium salt, bis(4-methylphenyl)iodonium salt, bis(4-tert-butylphenyl)iodonium salt, bis(dodecylphenyl)iodonium salt, 1,3-diketo- 2-diazo compound, diazobenzoquinone compound, diazonaphthoquinone compound, hexachloroantimonate, bis(dodecylphenyl)hexafluoroantimonate (4,4'-bis[di(β-hydroxy Ethoxy)phenylsulfonio]phenylsulfide, bis[4-(diphenylsulfonio)-phenyl]sulfide, bis[4-(di(4-(2-hydroxyethyl)phenyl)sulfonio )-phenyl]sulfide, η5-2,4-(cyclopentadienyl)[1,2,3,4,5,6-η-(methylethyl)benzene]-iron (1+), etc. As a specific example which can be obtained in the market of a photocationic polymerization initiator, the brand name "LW-S1" of San-Apro Corporation, etc. are mentioned.

As the thermal cationic polymerization initiator, triphenylsulfonium boron tetrafluoride, triphenylsulfonium antimony hexafluoride, triphenylsulfonium arsenic hexafluoride, tri(4-methoxyphenyl)sulfonium arsenic hexafluoride, diphenyl (4-phenylthiophenyl)sulfo Arsenic arsenic hexafluoride, p-t-butylbenzyltetrahydrothiophenium antimony hexafluoride, N,N-dimethyl-N-benzylanilinium antimony hexafluoride, N,N-dimethyl-N-benzylanilinium boron tetrafluoride, N,N- dimethyl-N-(4-chlorobenzyl)anilinium antimony hexafluoride, N,N-dimethyl-N-(1-phenylethyl)anilinium hexafluoride antimony, N-benzyl-4-dimethylaminopyridinium antimony hexafluoride, N-benzyl-4-diethylaminopyridinium trifluoromethanesulfonic acid, N-(4-methoxybenzyl)-4-dimethylaminopyridinium antimony hexafluoride, N-(4-methoxybenzyl)-4-di Ethylaminopyridinium antimony hexafluoride, N,N-dimethyl-N-(4-methoxybenzyl)toluidinium antimony hexafluoride, N,N-diethyl-N-(4-methoxybenzyl)toluidinium meat Antimony fluoride, ethyltriphenylphosphonium antimony hexafluoride, tetrabutylphosphonium antimony hexafluoride, diphenyliodonium arsenic hexafluoride, di-4-chlorophenyliodonium arsenic hexafluoride, di-4-bromphenyliodonium hexafluoride 1 or more types, such as arsenic, di-p-tolyliodonium arsenic hexafluoride, and a phenyl (4-methoxyphenyl) iodonium arsenic hexafluoride, are mentioned.

Moreover, instead of a thermal cationic polymerization initiator, you may use the photo-thermal cationic polymerization initiator applicable to either light or heat. Examples of the photo-thermal cationic polymerization initiator include sulfonium salts and iodonium salts, and among them, aromatic sulfonium salts having excellent reactivity at low temperatures and long pot life can be suitably used. As a specific example available in the market of a photothermal cationic polymerization initiator, Sanshin Chemical Co., Ltd. brand names "SI-60L", "SI-80L", "SI-100L", etc. are mentioned.

When the content of these cationic polymerization initiators is too small, the reactivity disappears, and when too large, the product life of the adhesive tends to decrease. Therefore, with respect to 100 parts by weight of the binder resin composition, preferably 0.1 to 30 parts by weight, more preferably 0.5 to 20 parts by weight.

Moreover, as a binder, you may mix|blend a stress reliever, a silane coupling agent, an inorganic filler, etc. as needed. Examples of the stress reliever include a hydrogenated styrene-butadiene block copolymer and a hydrogenated styrene-isoprene block copolymer. Moreover, as a silane coupling agent, an epoxy type, a methacryloxy type|system|group, an amino type, a vinyl type, a mercapto sulfide type, a ureido type, etc. are mentioned. Moreover, silica, talc, titanium oxide, calcium carbonate, magnesium oxide, etc. are mentioned as an inorganic filler.

[Example]

<3. Example>

Hereinafter, an embodiment of the present invention will be described. In this Example, the anisotropic conductive film was produced, the bonded structure was produced at various irradiation timings using this, and the conduction resistance and the curing rate of the bonded structure were evaluated. In addition, the present invention is not limited to these Examples.

Preparation of the bonded structure, the measurement of the conduction resistance, and the measurement and evaluation of the curing rate were performed as follows.

[Production of the connection structure]

As the evaluation substrate, a TI/Al coated glass substrate (metal wiring, t=0.7 mm) and IC (1.8 mm×20 mm, t=0.5 mm, Au-plated bump: 30 μm×85 μm, h=15 μm) were used. was used. Light irradiation conditions were 200 mW/cm 2 -3 seconds. In addition, thermocompression bonding conditions were made into 120 degreeC - 60 MPa-5 second.

[Measurement of conduction resistance]

The conduction resistance (Ω) of the bonded structure was measured using a digital multimeter (trade name: Digital Multimeter 7561, manufactured by Yokogawa Co., Ltd.).

[Measurement of curing rate]

IC was peeled from the bonded structure, and the sample A was acquired from the metal wiring top. Then, samples A to C were measured and the curing rate was calculated.

Sample A: Sample on metal wiring

Sample B: Sample of uncured anisotropic conductive film (before reaction)

Sample C: Sample B completely cured under light irradiation conditions of 200 mV/cm 2 -3 seconds and thermocompression bonding conditions of 120° C.-60 MPa-5 seconds

For each sample, FT-IR measurement was performed, and from the obtained IR chart, (I) 914 cm ⁻¹ : chronological stretching vibration of the epoxy ring and (II) 829 cm ⁻¹ : 2 peaks of angular oscillations outside the CH interface of aromatic rings was quantified. And about each sample, the absorbance ratio was calculated|required by following formula 1, and the hardening rate represented by following formula 2 was computed using the obtained absorbance ratio.

<Equation 1>

Absorbance ratio = (I) / (II)

<Equation 2>

Curing rate (%) = (1-absorbance ratio of sample A/absorbance ratio of sample B)/(1-absorbance ratio of sample C/absorbance ratio of sample B) x 100

[evaluation]

The case where the measurement result of conduction resistance was 1.0 ohm or less and the measurement result of the hardening rate of a wiring part was 70 % or more evaluated "OK", and evaluated other than that as "NG".

<Example 1>

As shown in FIG. 5, the anisotropic conductive film of a three-layer structure was produced. First, as the first layer 21, 20 parts by mass of a phenoxy resin (YP50, manufactured by Shin-Nitetsu Corporation), 30 parts by mass of a liquid epoxy resin (EP828, manufactured by Mitsubishi Chemical), and a solid epoxy resin (YD014, manufactured by Shin-Nitetsu Corporation). 20 mass parts and 30 mass parts of electroconductive particles (AUL704, Sekisui Chemical make) were mix|blended, and the 8-micrometer-thick A-layer was produced. In addition, as the second layer 22, 75 parts by mass of a phenoxy resin (YP50, manufactured by Shin-Nitetsu Chemical) and 25 parts by mass of a photocationic polymerization initiator (LW-S1, manufactured by San-Afro Corporation) were blended to have a thickness of 4 µm. An N-layer was prepared. Moreover, as the 3rd layer 23, the buffer layer of 4 micrometers in thickness containing a phenoxy resin (YP50, the Shinnitetsu Chemical make) was produced. And the A-layer, the buffer layer, and the N-layer were laminated, and the anisotropic conductive film of a three-layer structure was produced.

As shown in Fig. 6A, an anisotropic conductive film 52 was temporarily attached on a glass substrate 51, and ultraviolet rays were irradiated from above the anisotropic conductive film 52 under the light irradiation conditions before IC mounting. And as shown in FIG.6(B), the IC 53 was main-compressed-bonded under the said thermocompression bonding conditions 2 seconds after completion|finish of irradiation, and the bonded structure was obtained.

As shown in Table 1, the conduction resistance of the bonded structure of Example 1 was 0.7 ohm, and the hardening rate of the metal wiring part was 85 %, and the evaluation result was OK.

<Comparative Example 1>

An anisotropic conductive film having the same three-layer structure as in Example 1 was used. As shown in Fig. 7, after the IC was mounted, ultraviolet rays were irradiated from above the IC 53 under the above light irradiation conditions. And 2 seconds after completion|finish of irradiation, the IC 53 was main-compressed-bonded under the said thermocompression bonding conditions, and the bonded structure was obtained.

As shown in Table 1, the conduction resistance of the bonded structure of the comparative example 1 was 30 ohms, and the hardening rate of the metal wiring part was less than 5 %, and the evaluation result was NG.

<Comparative Example 2>

An anisotropic conductive film having the same three-layer structure as in Example 1 was used. As shown in FIG. 8 , after the IC was mounted on the anisotropic conductive film 52 , ultraviolet rays were irradiated from under the glass substrate 51 under the light irradiation conditions. And 2 seconds after completion|finish of irradiation, the IC 53 was main-compressed-bonded under the said thermocompression bonding conditions, and the bonded structure was obtained.

As shown in Table 1, the conduction resistance of the bonded structure of the comparative example 2 was 1.8 ohms, the hardening rate of the metal wiring part was 60 %, and the evaluation result was NG.

<Comparative Example 3>

An anisotropic conductive film having the same three-layer structure as in Example 1 was used. As shown in Fig. 9A, an anisotropic conductive film 52 was temporarily attached on the glass substrate 51, and ultraviolet rays were irradiated from below the glass substrate 51 under the above light irradiation conditions before IC mounting. Then, as shown in Fig. 9(B) , the IC 53 was subjected to main compression bonding under the thermocompression bonding conditions 2 seconds after the completion of irradiation to obtain a bonded structure.

As shown in Table 1, the conduction resistance of the bonded structure of the comparative example 3 was 1.8 ohms, the hardening rate of the metal wiring part was 60 %, and the evaluation result was NG.

<Comparative Example 4>

As shown in FIG. 10, the anisotropic conductive film of a two-layer structure was produced. First, 20 parts by mass of phenoxy resin (YP50, manufactured by Shin-Nitetsu Chemicals), 30 parts by mass of liquid epoxy resin (EP828, manufactured by Mitsubishi Chemical), 20 parts by mass of solid epoxy resin (YD014, manufactured by Shin-Nitetsu Chemical), light 5 parts by mass of a cationic polymerization initiator (LW-S1, manufactured by San Afro Co., Ltd.) and 30 parts by mass of conductive particles (AUL704, manufactured by Sekisui Chemical) were blended to prepare A-layer 61 having a thickness of 8 µm. Further, 20 parts by mass of phenoxy resin (YP50, manufactured by Shin-Nitetsu Chemicals), 30 parts by mass of liquid epoxy resin (EP828, manufactured by Mitsubishi Chemical), 20 parts by mass of solid epoxy resin (YD014, manufactured by Shin-Nitetsu Chemical) and light 5 parts by mass of a cationic polymerization initiator (LW-S1, manufactured by San-Afro Corporation) was blended to prepare an N-layer having a thickness of 10 µm. And the A-layer and the N-layer were laminated, and the anisotropic conductive film of a two-layer structure was produced.

As in Example 1, as shown in FIG. 6A, an anisotropic conductive film 52 is temporarily attached on the glass substrate 51, and before IC mounting, from above the anisotropic conductive film 52 to the light irradiation conditions UV light was irradiated. And as shown in FIG.6(B), the IC 53 was main-compressed-bonded under the said thermocompression bonding conditions 2 seconds after completion|finish of irradiation, and the bonded structure was obtained.

As shown in Table 1, the conduction resistance of the bonded structure of the comparative example 4 was 45 ohms, and the hardening rate of the metal wiring part was 90 %, and the evaluation result was NG.

<Comparative Example 5>

An anisotropic conductive film having the same two-layer structure as in Comparative Example 4 was used. Further, as in Comparative Example 2, as shown in FIG. 8 , after the IC was mounted on the anisotropic conductive film 52 , ultraviolet rays were irradiated from below the glass substrate 51 under the light irradiation conditions. And 2 seconds after completion|finish of irradiation, the IC 53 was main-compressed-bonded under the said thermocompression bonding conditions, and the bonded structure was obtained.

As shown in Table 1, the conduction resistance of the bonded structure of the comparative example 5 was 1.8 ohms, the hardening rate of the metal wiring part was 60 %, and the evaluation result was NG.

In Comparative Example 1, after mounting the IC on the anisotropic conductive film, ultraviolet rays were irradiated from above the IC, so the IC became a shadow, and the photocationic polymerization initiator could not be activated, and a good conduction resistance value and curing rate of the wiring part could be obtained. there was no

In Comparative Example 2, after mounting the IC on the anisotropic conductive film, ultraviolet rays were irradiated from below the glass substrate, so the transmission of ultraviolet rays was prevented, the activation of the photocationic polymerization initiator became insufficient, and the conduction resistance value and the curing rate of the wiring part were satisfactory. could not get

In Comparative Example 3, an anisotropic conductive film was temporarily affixed on a glass substrate, and ultraviolet rays were irradiated from below the glass substrate before IC mounting. As in Comparative Example 2, transmission of ultraviolet rays was prevented, and activation of the photocationic polymerization initiator became insufficient, and the The conduction resistance value and the curing rate of the wiring portion could not be obtained.

Comparative Example 4 used an anisotropic conductive film in which a cation-curable compound and a photocationic polymerization initiator were added in the same layer. Therefore, an anisotropic conductive film was temporarily attached on a glass substrate, and UV rays were irradiated from above the anisotropic conductive film before IC mounting. The conductive film was hardened, and the conduction resistance value was large due to insufficient press-fitting at the time of thermocompression bonding.

In Comparative Example 5, after the IC was mounted on the anisotropic conductive film, ultraviolet rays were irradiated from below the glass substrate, so as in Comparative Example 2, the transmission of ultraviolet rays was prevented, the activation of the photocationic polymerization initiator became insufficient, and the good conduction resistance value and The curing rate of the wiring portion could not be obtained.

On the other hand, in Example 1, using an anisotropic conductive film in which a cation-curable compound and a photocationic polymerization initiator were added to another layer, UV rays were irradiated from above the anisotropic conductive film before IC mounting, so the anisotropic conductive film was not cured, and photocationic The polymerization initiator could be activated, and the favorable conduction resistance value and the hardening rate of a wiring part were obtained.

10: first circuit member
20: anisotropic conductive film
21: first floor
22: second floor
23: 3rd floor
30: second circuit member
40: crimping tool
51: glass substrate
52: anisotropic conductive film
53: IC
61: A floor
62: N layer

Claims (13)

A light irradiation step of irradiating ultraviolet rays to an anisotropic conductive film in which a polymerizable compound and a photoinitiator are localized at different locations;
A thermocompression bonding process of thermocompression bonding the first circuit member and the second circuit member through the anisotropic conductive film
A method for manufacturing a bonded structure having
The manufacturing method of the bonded structure in which the said anisotropic conductive film has a 1st layer containing a polymeric compound and electroconductive particle, and a 2nd layer containing a photoinitiator and a nonpolymerizable compound. delete The method for producing a bonded structure according to claim 1, wherein the anisotropic conductive film has a third layer containing a non-polymerizable compound between the first layer and the second layer. According to claim 1, further comprising a temporary attachment step of temporarily attaching the anisotropic conductive film on the first circuit member,
In the said light irradiation process, the manufacturing method of the bonded structure which irradiates an ultraviolet-ray from the said anisotropic conductive film side. delete The method according to claim 3, further comprising a temporary attachment step of temporarily attaching an anisotropic conductive film on the first circuit member,
In the said light irradiation process, the manufacturing method of the bonded structure which irradiates an ultraviolet-ray from the said anisotropic conductive film side. The method for manufacturing a bonded structure according to claim 1, wherein the time from the completion of the irradiation of the ultraviolet rays to the thermocompression bonding is 10 seconds or less. delete The manufacturing method of the bonded structure of Claim 3 whose time from the completion of the said ultraviolet-ray irradiation to the said thermocompression bonding is 10 second or less. The manufacturing method of the bonded structure of Claim 4 whose time from the completion of the said ultraviolet-ray irradiation to the said thermocompression bonding is 10 second or less. The bonded structure obtained by the manufacturing method of the bonded structure in any one of Claims 1, 3, 4, 6, 7, 9, and 10. A first layer containing a polymerizable compound and conductive particles;
Second layer containing a photoinitiator and a non-polymerizable compound
An anisotropic conductive film having The anisotropic conductive film according to claim 12, having a third layer containing a non-polymerizable compound between the first layer and the second layer.

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