WO2015133211A1

WO2015133211A1 - Connecting structure, manufacturing method for connecting structure, and circuit connecting material

Info

Publication number: WO2015133211A1
Application number: PCT/JP2015/052637
Authority: WO
Inventors: 佐藤　伸一; 祐治田中
Original assignee: デクセリアルズ株式会社
Priority date: 2014-03-06
Filing date: 2015-01-30
Publication date: 2015-09-11
Also published as: JP6307308B2; KR20160130399A; JP2015170694A

Abstract

The present invention is a manufacturing method for a connecting structure having: a placement step which places a first circuit member (10), which is provided with a first terminal part (12) in which first terminals (12a) are arranged and a resist (13) which is formed around the first terminal part (12) and has a thickness greater than the height of the first terminals (12a), and a second circuit member (20), which is provided with a second terminal part (22) in which second terminals (22a), of a height lower than the first terminals (12a), are arranged, said first circuit member (10) and said second circuit member (20) being interposed by a circuit connecting material (30) having a first layer (31), which contains a film-forming resin and a polymerizable compound and is in contact with the first circuit member (10), and a second layer (32), which contains a film-forming resin, a polymerizable compound, a polymerization initiator, and conductive particles and is in contact with the second circuit member (20); and a compression step which performs thermocompression bonding on the first circuit member (10) and the second circuit member (20) at a predetermined temperature so as to acquire a connecting structure.

Description

Connection structure, method for manufacturing connection structure, and circuit connection material

The present invention relates to a connection structure using a circuit connection material such as an anisotropic conductive film, a manufacturing method thereof, and a circuit connection material.

Conventionally, anisotropic conductive films (ACF: Anisotropic Conductive Film) are used for connection of fine wiring that is not suitable for solder connection (see, for example, Patent Document 1). However, it has been used for connection of relatively rough wiring having a terminal width of 300 μm or more because of any advantage that enables low-temperature connection.

The anisotropic conductive film designed for general fine wiring is eliminated by flowing out of the terminal area against the force of the binder forming the adhesive layer crushing, and the thickness of the adhesive layer of the terminal portion is made of conductive particles. By being thinner than the diameter, the conductive particles are crushed, and the design is to obtain good conductivity. However, when a terminal area having a relatively large area is to be connected, it is difficult to appropriately remove the binder between the terminals, and when the removal is insufficient, the remaining binder prevents conduction. The lack of binder removal was particularly noticeable when a circuit member in which the periphery of a terminal portion where a plurality of terminals are arranged is covered with a solder resist having a thickness larger than the height of the terminal is subjected to low-temperature pressure bonding.

JP 2011-32491 A

The present invention solves the above-described problems in the prior art, and a connection structure that can obtain high connection reliability even when the periphery of the terminal portion is covered with a resist having a thickness larger than the terminal height, and The manufacturing method and circuit connection material are provided.

In order to solve the above-described problem, a manufacturing method of a connection structure according to the present invention includes a first terminal portion in which first terminals are arranged, and a periphery of the first terminal portion. A second circuit portion including a first circuit member including a resist having a thickness larger than the height of the first terminal, and a second terminal portion in which a second terminal having a lower height than the first terminal is arranged. A circuit member comprising a film-forming resin and a polymerizable compound, a first layer in contact with the first circuit member, the film-forming resin, the polymerizable compound, a polymerization initiator, and conductivity. A disposing step of interposing a circuit connecting material containing particles and having a second layer in contact with the second circuit member, and the first circuit member and the second circuit member A thermocompression bonding at a temperature to obtain a connection structure, and the film forming resin of the first layer Glass transition temperature, wherein said the predetermined temperature of -50 in ° C. or higher and the second layer film formation of the resin having a glass transition temperature of + 35 ° C. or higher.

Further, the connection structure according to the present invention is obtained by the method for manufacturing the connection structure.

The circuit connection material according to the present invention is formed around the first terminal portion in which the first terminals are arranged and the first terminal portion, and has a thickness larger than the height of the first terminal. A first circuit member having a resist and a second circuit member having a second terminal portion in which second terminals having a height lower than the terminals of the first circuit member are arranged. In the circuit connection material to be thermocompression-bonded, a film-forming resin and a polymerizable compound, a first layer in contact with the first circuit member, the film-forming resin, the polymerizable compound, and a polymerization initiator And a second layer in contact with the second circuit member, wherein the glass transition temperature of the film-forming resin of the first layer is not less than −50 ° C. of the predetermined temperature. And the glass transition temperature of the film-forming resin of the second layer is not less than + 35 ° C. That.

In the present invention, the glass transition temperature of the film-forming resin of the first layer of the circuit connecting material is not less than −50 ° C. of the predetermined temperature at the time of pressure bonding and + 35 ° C. of the glass transition temperature of the film-forming resin of the second layer. Therefore, even when the periphery of the terminal portion is covered with a resist having a thickness larger than the terminal height, high connection reliability can be obtained.

FIG. 1 is a cross-sectional view showing an example of the arrangement of the first circuit member, the second circuit member, and the circuit connection material. FIG. 2 is a plan view illustrating an example of a first circuit member including a resist formed around the terminal portion. FIG. 3 is a cross-sectional view showing a part of the terminal portion at AA in FIG.

Hereinafter, embodiments of the present invention will be described in detail in the following order.
1. 1. Manufacturing method of connection structure Example

<1. Manufacturing method of connection structure>
The manufacturing method of the connection structure according to the present embodiment includes at least an arrangement step and a crimping step, and further includes other steps as necessary.
In the arrangement step, the first circuit member and the second circuit member are arranged with a circuit connecting material interposed therebetween.
In the crimping step, the first circuit member and the second circuit member are thermocompression bonded at a predetermined temperature to obtain a connection structure.
The first circuit member includes a first terminal portion in which first terminals are arranged, a resist formed around the first terminal portion, and having a thickness larger than the height of the first terminal. Is provided.
The second circuit member includes a second terminal portion in which second terminals lower than the height of the first terminal are arranged.
The circuit connection material has a first layer in contact with the first circuit member and a second layer in contact with the second circuit member.

Hereinafter, each process will be described in detail.

[Arrangement process]
FIG. 1 is a cross-sectional view showing an arrangement of a first circuit member, a second circuit member, and a circuit connection material. In the disposing step, the first circuit member 10 and the second circuit member 20 have a first layer 31 in contact with the first circuit member 10 and a second layer 32 in contact with the second circuit member 20. The connecting material 30 is interposed.

FIG. 2 is a plan view showing an example of a first circuit member provided with a resist formed around the terminal portion, and FIG. 3 is a cross-sectional view showing a part of the terminal portion along AA in FIG. is there. FIG. 1 is a cross-sectional view showing a part of the terminal portion at BB in FIG.

As shown in FIGS. 1 to 3, the first circuit member 10 includes a first base material 11, a first terminal portion 12, and a resist 13.
A first terminal 12 a is arranged in the first terminal portion 12.
The resist 13 is formed around the first terminal portion 12. The resist 13 has a thickness t larger than the height h of the first terminal 12a.

The first base material 11 may be a base material used as an electronic circuit board material, such as a glass epoxy board or a glass board. The first terminal portion 12 has a plurality of first terminals 12 a arranged on the first base material 11. The height h of the first terminal 12a is, for example, 25 μm to 45 μm. The width of the first terminal 12a is not particularly limited, but in this embodiment, high connection reliability can be obtained even with a wide terminal of 300 μm or more.

The resist 13 is a solder resist that covers the surface of the first substrate 11 and serves as an insulating film that protects the circuit pattern. As shown in FIG. 2, the resist 13 covers the periphery of the first terminal portion 12, and as shown in FIG. 3, the resist 13 has a thickness larger than the height h of the first terminal 12a. t.

As such a first circuit member 10, for example, a glass substrate for IC (Integrated Circuit) mounting, a glass substrate for LCD (Liquid Crystal Display) panel, a plastic substrate such as cycloolefin (COP) for touch panel, A glass substrate etc. are mentioned.

The 2nd circuit member 20 is provided with the 2nd base material 21 and the 2nd terminal part 22 in which the 2nd terminal 22a was arranged, as shown in FIG. As the second base material 21, a base material used as an electronic circuit board material, such as polyimide, can be used. The second terminal portion 22 has a plurality of second terminals 22 a arranged on the second base material 21. The height of the second terminal 22a is, for example, 5 μm to 20 μm. Although the width of the second terminal 22a is not particularly limited, in the present embodiment, high connection reliability can be obtained even at 300 μm or more.

Examples of the second circuit member 20 include a flexible substrate (FPC: Flexible Printed Circuits) such as COF (Chip On Film) and TCP (Tape Carrier Package), an IC, and the like.

The circuit connection material 30 has a first layer 31 and a second layer 32.
The first layer 31 contains a film-forming resin and a polymerizable compound. The first layer 31 is in contact with the first circuit member 10.
The second layer 32 contains a film-forming resin, a polymerizable compound, a polymerization initiator, and conductive particles. The second layer 32 is in contact with the second circuit member 20.

The film-forming resin of the first layer 31 and the film-forming resin of the second layer 32 are such that the glass transition temperature of the film-forming resin of the first layer 31 is −50 ° C. or higher of the pressure-bonding temperature in the pressure-bonding step. The glass transition temperature of the film forming resin of the layer 32 is selected to be + 35 ° C. or higher. Thus, after the binder of the first layer 31 is appropriately excluded between the terminals, the second layer 32 containing conductive particles is not so much excluded between the left and right terminals and remains between the upper and lower terminals. Therefore, moderate conduction performance can be obtained.

When the glass transition temperature of the film-forming resin of the first layer 31 is less than −50 ° C., which is the pressure bonding temperature, the fluidity is excessive, and the binder removed between the terminals flows away to the outside of the terminals, Cannot fill between terminals. For this reason, floating occurs in the reliability test, and the conduction performance deteriorates. Further, when the glass transition temperature of the film-forming resin of the first layer 31 is higher than the pressure bonding temperature, the binder on the terminal may not be completely excluded. Therefore, the glass transition temperature of the film-forming resin of the first layer 31 is preferably equal to or lower than the pressure bonding temperature. Further, when the glass transition temperature of the film forming resin of the first layer 31 is less than + 35 ° C. of the glass transition temperature of the film forming resin of the second layer 32, the first layer 31 and the second layer 32 The binder will flow in the same manner and the conduction performance will be reduced.

The glass transition temperature of the film-forming resin can be calculated as a theoretical glass transition temperature represented by the following formula (1) (FOX formula).
1 / Tg = W1 / T1 + W2 / T2 +... Wn / Tn (1)
In the formula (1), W1, W2,... Wn are mass fractions of each monomer, and T1, T2,... Tn are glass transition temperatures (K) of the respective monomers.

As the film-forming resin, a thermoplastic elastomer such as phenoxy resin, epoxy resin, polyester resin, polyurethane resin, polyamide, EVA, or the like can be used. Among these, it is preferable to use a bisphenol A type phenoxy resin synthesized from bisphenol A and epichlorohydrin for heat resistance and adhesiveness.

The thickness of the first layer 31 is preferably 10% to 75% of the height of the first terminal 12a. Thereby, even when the periphery of the first terminal portion 12 is covered with the resist 13 having a thickness larger than the height of the first terminal 12a, high connection reliability can be obtained.

In addition, the polymerizable compound of the first layer 31 and the polymerizable compound of the second layer 32 are radical polymerizable compounds, and the polymerization initiator of the second layer 32 is an organic peroxide. preferable. Due to the incompatibility of the film-forming resin and the radically polymerizable compound, appropriate fluidity can be obtained.

Examples of the radical polymerizable compound include urethane acrylate, polyethylene glycol diacrylate, phosphate ester acrylate, tricyclodecane dimethanol dimethacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, isobutyl acrylate, t-butyl acrylate, isooctyl acrylate, bisphenoxyethanol full orange acrylate, 2-acryloyloxyethyl succinic acid, lauryl acrylate, stearyl acrylate, isobornyl acrylate, cyclohexyl acrylate, tris (2-hydroxyethyl) isocyanurate triacrylate, Tetrahydrofurfuryl acrylate, diglycidyl ether o-phthalate Relate, ethoxylated bisphenol A dimethacrylate, bisphenol A type epoxy acrylate, epoxy acrylate, and corresponding to these (meth) acrylate. Among these, it is preferable to use urethane acrylate and polyethylene glycol diacrylate in combination from the viewpoint of improving conduction reliability and improving adhesiveness.

Examples of organic peroxides include dilauroyl peroxide (1 minute half-life temperature 116.4 ° C.), dibenzoyl peroxide (1 minute half-life temperature 130.0 ° C.), di (4-methylbenzoyl) peroxide (1 Minute half-life temperature 128.2 ° C), di (3-methylbenzoyl) peroxide (1 minute half-life temperature 131.1 ° C), t-hexylperoxybenzoate (1 minute half-life temperature 160.3 ° C), t -Butyl peroxybenzoate (1 minute half-life temperature 166.8 ° C), 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (1 minute half-life temperature 124.3 ° C), di- (3,5,5-trimethylhexanoyl) peroxide (1 minute half-life temperature 112.6 ° C), t-butyl peroxypivalate (1 minute half-life temperature 10.3 ℃), and the like. Among these, it is preferable to use dilauroyl peroxide and dibenzoyl peroxide in combination from the viewpoint of improving conduction reliability and improving adhesiveness. The first layer 31 does not necessarily contain a polymerization initiator, but may be added in a small amount so as not to impair the effects of the invention.

Also, as the conductive particles of the second layer 32, known conductive particles used in anisotropic conductive films (ACF) can be used. Examples thereof include particles of various metals and metal alloys such as nickel, iron, copper, aluminum, tin, lead, chromium, cobalt, silver, and gold. Moreover, the thing which coat | covered the metal on the surface of particles, such as a metal oxide, carbon, a graphite, glass, a ceramic, a plastics, and what further coat | covered the insulating thin film on the surface of these particles etc. are mentioned. In the case where the surface of the resin particle is coated with a metal such as Ni or Au, examples of the resin particle include an epoxy resin, a phenol resin, an acrylic resin, an acrylonitrile / styrene (AS) resin, a benzoguanamine resin, and a divinylbenzene resin. Particles such as styrene resin can be used. The first layer 31 is not necessarily required to contain conductive particles, but may be added in a small amount so as not to impair the effects of the invention.

The first layer 31 and the second layer 32 may be diluted with other additives such as an acrylic ester copolymer resin (acrylic rubber), a silane coupling agent, and various acrylic monomers as necessary. Monomers, fillers, softeners, colorants, flame retardants, thixotropic agents, and the like may be added.

According to the circuit connection material 30 having such a configuration, even when the periphery of the first terminal portion 12 is covered with the resist 13 having a thickness larger than the height of the first terminal 12a, high connection reliability is obtained. be able to.

[Crimping process]
In the crimping step, the first circuit member and the second circuit member are thermocompression bonded at a predetermined temperature to obtain a connection structure. In the crimping step, for example, the second circuit member is pressed by using a crimping tool such as a heat tool. Here, the predetermined temperature refers to the temperature of the circuit connection material at the time of pressure bonding. Moreover, it is preferable that predetermined temperature is 100 degreeC or more and 180 degrees C or less.

Further, the thickness of the first layer between adjacent terminals after thermocompression bonding is preferably 1 μm or more and less than 10 μm. Thereby, a terminal part area | region is filled with a binder moderately, generation | occurrence | production of the float in a reliability test can be suppressed, and high connection reliability can be acquired.

Further, a buffer material may be interposed between the crimping tool and the second circuit member for crimping. By interposing the cushioning material, it is possible to reduce pressure variation and prevent the crimping tool from becoming dirty.

There is no restriction | limiting in particular as a crimping | compression-bonding tool, According to the objective, it can select suitably, You may perform a press once using the pressing member which is a larger area than a press target, The pressing may be performed in several times using a pressing member having a small area.

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, planar shape, curved surface shape, etc. are mentioned. In addition, when the tip shape is a curved surface shape, it is preferable to press along the curved surface shape.

According to such a method for manufacturing a connection structure, the glass transition temperature of the film-forming resin of the first layer of the circuit connection material is not less than −50 ° C., which is a predetermined temperature during pressure bonding, and the film-forming resin of the second layer Therefore, even when the periphery of the terminal portion is covered with a resist having a thickness larger than the terminal height, high connection reliability can be obtained.

<2. Example>
Examples of the present invention will be described below. In the present embodiment, the first layer in contact with the first circuit member and the second layer in contact with the second circuit member have a glass transition temperature Tg of the film forming resin of the first layer at a predetermined value. An anisotropic conductive film (ACF) was produced. Then, the first circuit member and the second circuit member are thermocompression bonded using ACF to produce a connection structure, and the connection structure has a conduction resistance, a peel strength, and a first between adjacent terminals after the compression bonding. The thickness of the layer was measured and evaluated. The present invention is not limited to these examples.

The production of ACF, the production of the connection structure, the conduction resistance of the connection structure, the peel strength, and the thickness of the first layer between the adjacent terminals after crimping were measured and evaluated as follows.

<Production of ACF>
Table 1 shows the composition of each layer. The composition of each layer shown in Table 1 (parts by mass) and a mixed solution of ethyl acetate and toluene so as to have a solid content of 50% by mass are each uniformly mixed by a conventional method to form the first layer. Compositions A1 to A6 and Composition B as the second layer were prepared. The glass transition temperature of the film-forming resin was calculated as a theoretical glass transition temperature represented by the following formula (1) (FOX formula).
1 / Tg = W1 / T1 + W2 / T2 +... Wn / Tn (1)
In the formula (1), W1, W2,... Wn are mass fractions of each monomer, and T1, T2,... Tn are glass transition temperatures (K) of the respective monomers.

Composition A1 comprises 54 parts by mass of phenoxy resin (trade name: jER4256, Mitsubishi Chemical Corporation), 25 parts by mass of urethane acrylate (trade name: U-2PPA, Shin-Nakamura Chemical Co., Ltd.), bifunctional acrylate ( Product name: A-200, Shin-Nakamura Chemical Co., Ltd.) 20 parts by mass. The glass transition temperature Tg of the film-forming resin is 65 ° C.

Composition A2 is composed of 54 parts by mass of phenoxy resin (trade name: jER1256, Mitsubishi Chemical Corporation), 25 parts by mass of urethane acrylate (trade name: U-2PPA, Shin-Nakamura Chemical Co., Ltd.), and bifunctional acrylate ( Product name: A-200, Shin-Nakamura Chemical Co., Ltd.) 20 parts by mass. The glass transition temperature Tg of the film-forming resin is 98 ° C.

Composition A3 is composed of 54 parts by mass of phenoxy resin (trade name: YX8100, Mitsubishi Chemical Co., Ltd.), 25 parts by mass of urethane acrylate (trade name: U-2PPA, Shin-Nakamura Chemical Co., Ltd.), bifunctional acrylate ( Product name: A-200, Shin-Nakamura Chemical Co., Ltd.) 20 parts by mass. The glass transition temperature Tg of the film forming resin is 150 ° C.

Composition A4 consists of 27 parts by mass of phenoxy resin (trade name: jER4256, Mitsubishi Chemical Corporation), 27 parts by mass of phenoxy resin (trade name: jER1256, Mitsubishi Chemical Corporation), and urethane acrylate (trade name: U -2PPA, 25 parts by mass of Shin-Nakamura Chemical Co., Ltd. and 20 parts by mass of bifunctional acrylate (trade name: A-200, Shin-Nakamura Chemical Co., Ltd.). The glass transition temperature Tg of the film forming resin is 81 ° C.

Composition A5 is composed of 27 parts by mass of phenoxy resin (trade name: jER4256, Mitsubishi Chemical Corporation), 27 parts by mass of phenoxy resin (trade name: YX8100, Mitsubishi Chemical Corporation), and urethane acrylate (trade name: U -2PPA, 25 parts by mass of Shin-Nakamura Chemical Co., Ltd. and 20 parts by mass of bifunctional acrylate (trade name: A-200, Shin-Nakamura Chemical Co., Ltd.). The glass transition temperature Tg of the film forming resin is 103 ° C.

Composition A6 is composed of 27 parts by mass of phenoxy resin (trade name: jER1256, Mitsubishi Chemical Corporation), 27 parts by mass of phenoxy resin (trade name: YX8100, Mitsubishi Chemical Corporation), and urethane acrylate (trade name: U -2PPA, 25 parts by mass of Shin-Nakamura Chemical Co., Ltd. and 20 parts by mass of bifunctional acrylate (trade name: A-200, Shin-Nakamura Chemical Co., Ltd.). The glass transition temperature Tg of the film forming resin is 122 ° C.

Composition B consists of 46 parts by mass of phenoxy resin (trade name: jER4256, Mitsubishi Chemical Corporation), 25 parts by mass of urethane acrylate (trade name: U-2PPA, Shin-Nakamura Chemical Co., Ltd.), bifunctional acrylate ( Trade name: A-200, Shin-Nakamura Chemical Co., Ltd. 20 parts by mass, phosphate ester acrylate (trade name: PM-2, Nippon Kayaku Co., Ltd.) 1 part by mass, Ni particles (nickel powder, An average particle diameter of 3 μm, 2 parts by weight of Bahrainco Co., Ltd., 3 parts by weight of dilauroyl peroxide, and 3 parts by weight of dibenzoyl peroxide are contained. The glass transition temperature Tg of the film-forming resin is 65 ° C.

Compositions A1 to A6 and B shown in Table 1 were applied to the release polyester film layer by layer, and dried by blowing hot air at 70 ° C. for 5 minutes to produce an adhesive film for each layer. A layer composed of the composition B and a layer composed of the composition B were laminated to produce an ACF having a two-layer structure.

<Production of connection structure>
The first circuit member and the second circuit member were joined via the ACF described above to produce a connection structure.
As a first circuit member, a printed wiring board (glass epoxy board, Cu thickness 35 μm, 200 μm P (pitch) (line: space = 1: 1) having a resist having a thickness larger than the height of the terminal around the terminal portion. ), Au flash plating product). The resist was formed as follows. A solder resist (PSR-4000) manufactured by Taiyo Ink Manufacturing Co., Ltd. was applied on a printed wiring board (PWB) to a film thickness of 40 μm after drying by screen printing or spray coating, and temporarily applied at 80 ° C. for 30 min. Drying was performed. After drying, the exposed portion was photocured through a photomask, and the unexposed portion was removed with a 1% sodium carbonate aqueous solution. Then, the exposed portion was heated and dried under the conditions of 150 ° C. and 60 min to be cured, and an evaluation base material having a resist with an opening range of the terminal portion of 2.0 mm × 40 mm was produced. An evaluation base material of 300 μm P (pitch) (line: space = 1: 1) was also produced in the same manner. That is, the evaluation base material has a terminal height h of 35 μm and a resist thickness t of 40 μm in the first circuit member 10 shown in FIG.

Also, as the second circuit member, a COF substrate (polyimide film thickness 38 μm, Cu thickness 8 μm, 200 μm P (pitch) (line: space = 1: 1), Sn plated product) was used. A COF substrate of 300 μm P (pitch) (line: space = 1: 1) was also used.

The connection between PWB and COF was performed under the following pressure bonding conditions.
-ACF width: 2.0 mm
・ Tool width: 2.0mm
-Buffer material: Silicone rubber thickness 200μm
Heating and pressing: 140 ° C to 170 ° C / 2MPa / 3sec

Also, the thickness of the first layer of ACF between adjacent terminals after crimping was measured by cross-sectional observation.

<Measurement and evaluation of conduction resistance>
The connection structure of 200 μmP and 300 μmP was subjected to a voltage when a constant current of 1 mA was applied using a tester by a four-terminal method with a conduction resistance [initial conduction resistance (Ω) and environmental test (85 ° C., 85% RH, 1000 h), the conduction resistance (Ω)] was measured and evaluated according to the following criteria.
[Evaluation criteria for initial conduction resistance]
○: Conduction resistance is less than 0.070Ω Δ: Conduction resistance is 0.070Ω or more and less than 0.100Ω ×: Conduction resistance is 0.100Ω or more [Evaluation criteria of conduction resistance after environmental test]
○: (initial conduction resistance / conduction resistance after environmental test) is less than 5 times Δ: (conduction resistance after environmental test / initial conduction resistance) is 5 times or more and less than 11 times ×: (conduction resistance after environmental test) / Initial conduction resistance) is more than 11 times

<Measurement and evaluation of peel strength>
About the connection structure of 200 μm P, the 90 ° Y-axis direction peel strength was measured at a pulling speed of 50 mm / min, and evaluated according to the following criteria. The results are shown by the maximum peel strength (N / cm).
〔Evaluation criteria〕
○: Peel strength is 10 N / cm or more Δ: Peel strength is 8 N / cm or more and less than 10 N / cm x: Peel strength is less than 8 N / cm

<Example 1>
As shown in Table 2, ACFs were prepared in which the first layer was 20 μm thick composed of composition A3 and the second layer was 20 μm thick composed of composition B. The glass transition temperature Tg of the film-forming resin of the first layer was 150 ° C.

1st circuit member and 2nd circuit member were crimped | bonded at 170 degreeC via ACF of Example 1, and the connection structure was produced. The thickness of the 1st layer between the adjacent terminals after crimping was less than 10 micrometers.

The initial resistance of the 200 μmP connection structure was evaluated as “good”.
The initial resistance of the 300 μmP connection structure was evaluated as “good”.
The evaluation of the resistance after the reliability test of the connection structure of 200 μmP was ○.
The evaluation of the resistance after the reliability test of the connection structure of 300 μm P was ○.
The evaluation of the peel strength of the connection structure was Δ.

<Example 2>
As shown in Table 2, an ACF was produced in which the first layer was 20 μm thick composed of the composition A5 and the second layer was 20 μm thick composed of the composition B. The glass transition temperature Tg of the film-forming resin of the first layer was 103 ° C.

1st circuit member and 2nd circuit member were crimped | bonded at 140 degreeC via ACF of Example 2, and the connection structure was produced. The thickness of the 1st layer between the adjacent terminals after crimping was less than 10 micrometers.

The initial resistance of the 200 μmP connection structure was evaluated as “good”.
The initial resistance of the 300 μmP connection structure was evaluated as “good”.
The evaluation of the resistance after the reliability test of the connection structure of 200 μmP was ○.
The evaluation of the resistance after the reliability test of the connection structure of 300 μm P was ○.
The evaluation of the peel strength of the connection structure was “good”.

<Example 3>
As shown in Table 2, an ACF was produced in which the first layer was 20 μm thick composed of the composition A6 and the second layer was 20 μm thick composed of the composition B. The glass transition temperature Tg of the film-forming resin of the first layer was 122 ° C.

1st circuit member and 2nd circuit member were crimped | bonded at 150 degreeC via ACF of Example 3, and the connection structure was produced. The thickness of the 1st layer between the adjacent terminals after crimping was less than 10 micrometers.

<Example 4>
As shown in Table 2, an ACF having a first layer of 10 μm thickness made of composition A5 and a second layer made of composition B having a thickness of 30 μm was prepared. The glass transition temperature Tg of the film-forming resin of the first layer was 103 ° C.

1st circuit member and 2nd circuit member were crimped | bonded at 150 degreeC via ACF of Example 4, and the connection structure was produced. The thickness of the first layer between adjacent terminals after the crimping was less than 3 μm.

<Example 5>
As shown in Table 2, ACFs were prepared in which the first layer was 5 μm thick composed of composition A5 and the second layer was 35 μm thick composed of composition B. The glass transition temperature Tg of the film-forming resin of the first layer was 103 ° C.

1st circuit member and 2nd circuit member were crimped | bonded at 140 degreeC via ACF of Example 4, and the connection structure was produced. The thickness of the first layer between the adjacent terminals after the crimping was less than 1 μm.

The initial resistance of the 200 μmP connection structure was evaluated as “good”.
The initial resistance of the 300 μmP connection structure was evaluated as “good”.
The evaluation of the resistance after the reliability test of the connection structure of 200 μmP was ○.
The evaluation of the resistance after the reliability test of the connection structure of 300 μm P was Δ.
The evaluation of the peel strength of the connection structure was “good”.

<Example 6>
As shown in Table 2, an ACF having a first layer of 25 μm thickness made of the composition A5 and a second layer made of the composition B of 15 μm thickness was prepared. The glass transition temperature Tg of the film-forming resin of the first layer was 103 ° C.

1st circuit member and 2nd circuit member were crimped | bonded at 140 degreeC via ACF of Example 4, and the connection structure was produced. The thickness of the first layer between the adjacent terminals after crimping was less than 15 μm.

<Comparative Example 1>
As shown in Table 3, an ACF was produced in which the first layer was 20 μm thick composed of the composition A1, and the second layer was 20 μm thick composed of the composition B. The glass transition temperature Tg of the film-forming resin of the first layer was 65 ° C.

The first circuit member and the second circuit member were crimped at 170 ° C. via the ACF of Comparative Example 1 to produce a connection structure. The thickness of the 1st layer between the adjacent terminals after crimping was less than 10 micrometers.

The initial resistance of the 200 μmP connection structure was evaluated as “good”.
The initial resistance of the 300 μmP connection structure was evaluated as “good”.
The evaluation of the resistance after the reliability test of the connection structure of 200 μmP was ○.
The evaluation of the resistance after the reliability test of the connection structure of 300 μm P was x.
The evaluation of the peel strength of the connection structure was “good”.

<Comparative example 2>
As shown in Table 3, an ACF was produced in which the first layer was 20 μm thick composed of the composition A2, and the second layer was 20 μm thick composed of the composition B. The glass transition temperature Tg of the film forming resin of the first layer was 98 ° C.

The first circuit member and the second circuit member were crimped at 170 ° C. via the ACF of Comparative Example 2 to produce a connection structure. The thickness of the 1st layer between the adjacent terminals after crimping was less than 10 micrometers.

<Comparative Example 3>
As shown in Table 3, an ACF was produced in which the first layer was 20 μm thick composed of the composition A4 and the second layer was 20 μm thick composed of the composition B. The glass transition temperature Tg of the first layer film-forming resin was 81 ° C.

The first circuit member and the second circuit member were crimped at 170 ° C. via the ACF of Comparative Example 3 to produce a connection structure. The thickness of the 1st layer between the adjacent terminals after crimping was less than 10 micrometers.

<Comparative example 4>
As shown in Table 3, an ACF having a first layer having a thickness of 20 μm made of the composition B and a second layer having a thickness of 20 μm made of the composition A3 was produced. The glass transition temperature Tg of the film-forming resin of the first layer was 65 ° C.

The first circuit member and the second circuit member were crimped at 170 ° C. via the ACF of Comparative Example 4 to produce a connection structure. The thickness of the first layer between adjacent terminals after the crimping was less than 3 μm.

The initial resistance of the 200 μmP connection structure was evaluated as Δ.
The initial resistance of the 300 μmP connection structure was evaluated as Δ.
The evaluation of the resistance after the reliability test of the connection structure of 200 μm P was x.
The evaluation of the resistance after the reliability test of the connection structure of 300 μm P was x.
The peel strength of the connection structure was evaluated as x.

<Comparative Example 5>
As shown in Table 3, an ACF having a thickness of 20 μm made of the composition B as the first layer and a thickness of 20 μm made of the composition A5 was prepared as the second layer. The glass transition temperature Tg of the film-forming resin of the first layer was 65 ° C.

The first circuit member and the second circuit member were crimped at 170 ° C. via the ACF of Comparative Example 5 to produce a connection structure. The thickness of the first layer between adjacent terminals after the crimping was less than 3 μm.

<Comparative Example 6>
As shown in Table 3, an ACF having a first layer having a thickness of 20 μm made of the composition B and a second layer having a thickness of 20 μm made of the composition A6 was produced. The glass transition temperature Tg of the film-forming resin of the first layer was 65 ° C.

The first circuit member and the second circuit member were crimped at 170 ° C. via the ACF of Comparative Example 6 to produce a connection structure. The thickness of the first layer between adjacent terminals after the crimping was less than 3 μm.

<Comparative Example 7>
As shown in Table 3, an ACF composed of the composition B and having a thickness of 40 μm was produced. The first circuit member and the second circuit member were pressure-bonded at 170 ° C. via the ACF of Comparative Example 7 to produce a connection structure.

The initial resistance of the 200 μmP connection structure was evaluated as “good”.
The initial resistance of the 300 μmP connection structure was evaluated as “good”.
The evaluation of the resistance after the reliability test of the connection structure of 200 μm P was Δ.
The evaluation of the resistance after the reliability test of the connection structure of 300 μm P was x.
The evaluation of the peel strength of the connection structure was “good”.

<Comparative Example 8>
As shown in Table 3, an ACF having a thickness of 20 μm made of the composition A3 as the first layer and a thickness of 20 μm made of the composition B as the second layer was prepared. The glass transition temperature Tg of the film-forming resin of the first layer was 150 ° C.

The first circuit member and the second circuit member were crimped at 140 ° C. via the ACF of Comparative Example 8 to produce a connection structure. The thickness of the 1st layer between the adjacent terminals after crimping was less than 10 micrometers.

The initial resistance of the 200 μmP connection structure was evaluated as “good”.
The initial resistance of the 300 μmP connection structure was evaluated as Δ.
The evaluation of the resistance after the reliability test of the connection structure of 200 μm P was Δ.
The evaluation of the resistance after the reliability test of the connection structure of 300 μm P was x.
The evaluation of the peel strength of the connection structure was “good”.

As shown in Table 3, in the ACFs of Comparative Examples 1 to 3, the glass transition temperature of the film forming resin of the first layer is not −50 ° C. or higher of the pressure bonding temperature, and the film forming resin of the second layer Since the glass transition temperature is not higher than + 35 ° C., when trying to connect a circuit member with a relatively wide 300 μm pitch, the fluidity becomes excessive and the space between terminals cannot be sufficiently filled. As a result, high connection reliability could not be obtained.

The ACFs of Comparative Examples 4 to 6 were obtained by changing the composition of the first layer and the composition of the second layer of Examples 1 to 3 into the second layer and the first layer, respectively. The capture rate of conductive particles was poor, and the initial conduction resistance was high. The peel strength was also low.

Further, since the ACF of Comparative Example 7 has a single-layer structure composed of the composition B, the binder between terminals is not sufficiently removed, and high connection reliability cannot be obtained. Further, Comparative Example 8 has a low pressure bonding temperature, and the glass transition temperature of the first layer film-forming resin is not higher than the pressure bonding temperature of −50 ° C. Could not get.

on the other hand. In the ACFs of Examples 1 to 6, the glass transition temperature of the film-forming resin of the first layer is not lower than −50 ° C. of the pressure-bonding temperature and + 35 ° C. of the glass transition temperature of the film-forming resin of the second layer. The binder between the terminals could be removed moderately and high connection reliability could be obtained.

Further, from Examples 5 and 6, when the thickness of the first layer is about 10% to 75% of the height of the first terminal, the resist around the terminal portion has a thickness larger than the terminal height. It was found that high connection reliability can be obtained even when covered with

Further, from Examples 1 to 6, when the thickness of the first layer between the adjacent terminals after crimping is 1 μm or more and less than 10 μm, the terminal area is appropriately filled with the binder, and the occurrence of floating in the reliability test is generated. It was found that high connection reliability can be obtained.

DESCRIPTION OF SYMBOLS 10 1st circuit member 11 1st base material 12 1st terminal part 12a 1st terminal 13 Resist 20 2nd circuit member 21 2nd base material 22 2nd terminal part 22a 2nd terminal 30 Circuit Connecting material 31 First layer 32 Second layer

Claims

A first circuit member comprising: a first terminal portion in which first terminals are arranged; and a resist formed around the first terminal portion and having a thickness larger than the height of the first terminal; A second circuit member including a second terminal portion in which second terminals having a height lower than that of the first terminal are arranged, containing a film-forming resin and a polymerizable compound, A first layer in contact with one circuit member, a film-forming resin, a polymerizable compound, a polymerization initiator, and conductive particles, and a second layer in contact with the second circuit member. A placement step of placing the circuit connection material in between;
A thermocompression bonding of the first circuit member and the second circuit member at a predetermined temperature to obtain a connection structure,
A method for manufacturing a connection structure, wherein the glass transition temperature of the film forming resin of the first layer is −50 ° C. or more of the predetermined temperature and + 35 ° C. or more of the glass transition temperature of the film forming resin of the second layer.
The method for manufacturing a connection structure according to claim 1, wherein the thickness of the first layer is 10% to 75% of the height of the first terminal.
The polymerizable compound of the first layer is a radically polymerizable compound;
The polymerizable compound of the second layer is a radically polymerizable compound;
The method for producing a connection structure according to claim 1 or 2, wherein the polymerization initiator of the second layer is an organic peroxide.
The method for manufacturing a connection structure according to any one of claims 1 to 3, wherein a width of the first terminal is 300 µm or more.
The method for manufacturing a connection structure according to any one of claims 1 to 3, wherein a thickness of the first layer between adjacent terminals after thermocompression bonding is 1 µm or more and less than 10 µm.
A connection structure obtained by the method for manufacturing a connection structure according to any one of claims 1 to 5.
A first circuit member comprising: a first terminal portion in which first terminals are arranged; and a resist formed around the first terminal portion and having a thickness larger than the height of the first terminal; In the circuit connection material for thermocompression bonding at a predetermined temperature with the second circuit member provided with the second terminal portion in which the second terminals lower in height than the terminals of the first circuit member are arranged,
A first layer containing a film-forming resin and a polymerizable compound and in contact with the first circuit member;
A film-forming resin, a polymerizable compound, a polymerization initiator, a conductive particle, and a second layer in contact with the second circuit member;
The circuit connecting material, wherein the glass transition temperature of the film forming resin of the first layer is not less than −50 ° C. of the predetermined temperature and + 35 ° C. of the glass transition temperature of the film forming resin of the second layer.