KR20140146059A

KR20140146059A - Circuit connection material, connection structure, and fabrication method for same

Info

Publication number: KR20140146059A
Application number: KR1020147024584A
Authority: KR
Inventors: 다카시 나카자와; 겐조우 다케무라
Original assignee: 히타치가세이가부시끼가이샤
Priority date: 2012-04-13
Filing date: 2013-04-15
Publication date: 2014-12-24
Also published as: CN104093799A; KR102044574B1; JPWO2013154203A1; JP6107816B2; WO2013154203A1; CN104093799B

Abstract

According to the present invention, the first circuit member having the first circuit electrode formed on the main surface of the first substrate, and the second circuit member having the second circuit electrode formed on the main surface of the second substrate, A radical polymerization initiator, a radical polymerizable substance, and a thiol compound having a thiol group and having 1 or 0 hydrogen atoms bonded to the carbon atom bonded to the thiol group, , And the content of the thiol compound is 7 to 17 parts by mass relative to 100 parts by mass of the radical polymerizable material.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a circuit connecting material, a connection structure,

The present invention relates to a circuit connecting material for electrically connecting electrodes in a pressing direction by pressing circuit electrodes opposed to each other between circuit electrodes facing each other, a connection structure using the circuit connecting material, and a manufacturing method thereof.

As a circuit connecting material for a semiconductor element or a liquid crystal display element, a thermosetting resin using an epoxy resin exhibiting high adhesiveness and high reliability is known (see, for example, Patent Document 1). As a constituent component of the resin, a curing agent such as an epoxy resin, a phenol resin having reactivity with the epoxy resin, and a latent curing agent for promoting the reaction between the epoxy resin and the curing agent are generally used. The latent curing agent is an important factor for determining the curing temperature and the curing rate, and various compounds are used in view of the storage stability at room temperature and the curing rate at the time of heating.

In recent years, radical-curing adhesives using acrylate derivatives and / or methacrylate derivatives (hereinafter collectively referred to as " (meth) acrylate derivatives ") and peroxides as radical polymerization initiators have been attracting attention. Radical curing is capable of short-time curing because the reactive radicals are rich in reactivity (see, for example, Patent Documents 2 and 3).

As a result, a short-time curing type adhesive which is advantageous for shortening the production time is spreading nowadays. For the purpose of further improving the reactivity of the radical curing type adhesive, application of a chain transfer agent has been studied (see, for example, Patent Documents 4 and 5).

JP-A-1-113480 Japanese Patent Application Laid-Open No. 2002-203427 International Publication WO98 / 044067 brochure Japanese Patent Application Laid-Open No. 2003-221557 International Publication WO2009 / 057376 brochure

In recent years, in view of the application of a small-sized module such as a cellular phone, a circuit connecting material has been considered as a substitute member of a connector from the viewpoint of making the module thinner. Since the connection pitch of the circuit members in such a small module is more steeper than the connection pitch (for example, 0.4 mm or less) of the circuit members to which the conventional circuit connection material has been applied, do.

For example, a circuit connecting material to be used as a substitute member of a connector requires a higher adhesive force because the length of the connecting portion is shorter than that of a conventional field (for use in semiconductor devices, liquid crystal display devices, and the like). For example, in a conventional connection for a peripheral member of a liquid crystal panel, an adhesive force of 6 N / cm or more is generally required, but an adhesive force of 12 N / cm or more may be required as a substitute member of the connector.

On the other hand, the connection of a rough pitch (for example, a connection pitch of 0.5 mm or more) tends to reduce the adhesive force even when the same circuit connecting material is used as compared with the connection with a fine pitch. This is presumably because the number of electrodes per unit length is reduced, so that the adhesive force in the shear direction generated at the interface between the electrode wall and the circuit connecting material decreases.

Accordingly, it is an object of the present invention to provide a circuit connecting material which can obtain a sufficiently high adhesive force even in rough pitch connection, and which has excellent connection reliability, and a connection structure using the circuit connecting material and a method of manufacturing the same.

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have found that a circuit connecting material exhibiting a high adhesive force and a good connection reliability can be obtained by containing a specified amount of a specific chain transfer agent, Thereby completing the present invention.

That is, the present invention is characterized in that the first circuit member having the first circuit electrode formed on the main surface of the first substrate and the second circuit member having the second circuit electrode formed on the main surface of the second substrate, A radical polymerization initiator, a radical polymerizable substance, and a thiol compound having a thiol group and having 1 or 0 hydrogen atoms bonded to the carbon atom bonded to the thiol group, , And the content of the thiol compound is 7 to 17 parts by mass relative to 100 parts by mass of the radical polymerizable material.

According to such a circuit connecting material, a sufficiently high adhesive force can be obtained even at the connection of rough pitch. In addition, a circuit connecting material used as a substitute member of a connector is required to have a good connection reliability for the connecting structure connected by using the circuit connecting material. According to the circuit connecting material of the present invention, a sufficiently high adhesive force and a good connection reliability at the time of rough pitch connection can be achieved at the same time. Further, according to the circuit connecting material of the present invention, since the thiol compound functions as a chain transfer agent, the curing speed is high and the short-time low-temperature connection can be realized, and the effect of improving the adhesion to an inorganic substance such as a metal is effective .

In the circuit connecting material according to the present invention, the molecular weight of the thiol compound is preferably 400 or more. Such a circuit connecting material has a higher adhesive force at the time of rough pitch connection and more excellent connection reliability.

In the circuit connecting material of the present invention, the first circuit member (or the second circuit member) may be formed on the main surface of the first substrate (or the second substrate) And the electrode (or the second substrate) are formed. Since the circuit connecting material of the present invention can obtain a sufficiently high adhesive force even at the rough pitch connection, it can be suitably used for connecting the circuit member as described above.

The present invention is also characterized in that a first circuit member having a first circuit electrode formed on the main surface of the first substrate and a second circuit electrode formed on the main surface of the second substrate, And an adhesive layer formed between the first circuit member and the second circuit member and electrically connecting the first circuit member and the second circuit member to each other, , And the circuit connecting material is interposed between the first circuit member and the second circuit member and is heated and pressurized.

Since such a connection structure uses the circuit connecting material of the present invention, the first circuit member and the second circuit member are bonded with high adhesive force. Further, the first circuit member and the second circuit member are connected with good connection reliability. Therefore, the connection structure according to the present invention is excellent in durability, heat resistance and moisture resistance.

The present invention also provides a circuit board comprising: a first circuit member having a first circuit electrode formed on a main surface of a first substrate; a second circuit member having a second circuit electrode formed on a main surface of the second substrate; And a step of electrically connecting the first circuit electrode and the second circuit electrode by heating and pressing in a state in which the circuit electrode and the second circuit electrode are disposed so as to face each other through the circuit connecting material, Of the present invention. According to this manufacturing method, the connection structure according to the present invention can be easily obtained.

According to the present invention, it is possible to provide a circuit connecting material which can obtain a sufficiently high adhesive force even in a rough pitch connection, and which has excellent connection reliability, a connection structure using the circuit connecting material, and a manufacturing method thereof.

1 is a schematic cross-sectional view showing an embodiment of a connection structure according to the present invention.

A preferred embodiment of the circuit connecting material and the connection structure according to the present invention will be described below.

The circuit connecting material according to the present embodiment contains a radical polymerization initiator, a radical polymerizable substance, and a thiol compound having a thiol group and having 1 or 0 hydrogen atoms bonded to the carbon atom bonded to the thiol group. The content of the thiol compound is 7 to 17 parts by mass based on 100 parts by mass of the radical polymerizable substance.

The circuit connecting material according to the present embodiment has a first circuit member on which a first circuit electrode is formed on a main surface of a first substrate and a second circuit member on which a second circuit electrode is formed on a main surface of the second substrate, And the second circuit electrode in a state in which they are opposed to each other.

According to the circuit connecting material of the present embodiment, it is possible to obtain a sufficiently high adhesive force at the time of rough pitch connection. Further, according to the circuit connecting material of the present embodiment, a connection structure having good connection reliability can be obtained even when used for rough pitch connection. As a result, the circuit connecting material according to the present embodiment can be used particularly suitably for connecting circuit members having a rough pitch (connection pitch of 0.5 mm or more).

The radical polymerization initiator is a compound which generates a free radical and may be referred to as a free radical generator. As the radical polymerization initiator, a compound which is decomposed by heating with a peroxide compound, an azo compound or the like to generate a free radical is suitable. The radical polymerization initiator is appropriately selected according to the intended connection temperature, connection time, and the like.

The content of the radical polymerization initiator in the circuit connecting material is preferably 0.05 to 10% by mass, more preferably 0.1 to 5% by mass.

Examples of the radical polymerization initiator include diacyl peroxides, peroxydicarbonates, peroxyesters, peroxycetals, dialkyl peroxides, hydroperoxides and the like.

Examples of diacyl peroxides include 2,4-dichlorobenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, lauroyl peroxide, stearoyl peroxide, succinic peroxide, Peroxy toluene, benzoyl peroxide, and the like.

Examples of peroxydicarbonates include di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, bis (4-t-butylcyclohexyl) peroxydicarbonate, di- Di (3-methyl-3-methoxybutylperoxy) dicarbonate, and the like can be given as examples of the organic peroxides such as methoxy peroxydicarbonate, di (2-ethylhexylperoxy) dicarbonate, dimethoxybutyl peroxydicarbonate, have.

Examples of peroxy esters include 1,1,3,3-tetramethylbutyl peroxyneodecanoate, 1-cyclohexyl-1-methylethylperoxino edecanoate, t-hexyl peroxyneodecanoate butyl peroxypivalate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-di (2-ethylhexanoylperoxy) Hexyl peroxy-2-ethyl hexanoate, t-butyl peroxy-2-ethyl hexanoate, t-butyl peroxy-2-ethyl hexanoate, Peroxyisobutyrate, 1,1-bis (t-butylperoxy) cyclohexane, t-hexylperoxyisopropyl monocarbonate, t-butylperoxy-3,5,5-trimethylhexanonate, t Butyl peroxylaurate, 2,5-dimethyl-2,5-di (m-toluoylperoxy) hexane, t-butylperoxyisopropyl monocarbonate, t- Monocarbonate, t-hexyl peroxybenzoate, t-butyl peroxyacetate And the like.

As the peroxyketalization, 1,1-bis (t-hexylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-hexylperoxy) cyclohexane, butylperoxy) -3,3,5-trimethylcyclohexane, 1,1- (t-butylperoxy) cyclododecane, 2,2-bis (t-butylperoxy) decane and the like .

Examples of the dialkyl peroxides include α, α "-bis (t-butylperoxy) diisopropylbenzene, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) t-butylcumyl peroxide and the like.

Examples of hydroperoxides include diisopropylbenzene hydroperoxide, cumene hydroperoxide and the like.

These radical polymerization initiators may be used alone or in combination, and a decomposition accelerator, an inhibitor, or the like may be mixed and used. In addition, microcapsules prepared by coating these radical polymerization initiators with polyurethane-based, polyester-based high molecular materials or the like are preferable because their preservability is prolonged.

The radical polymerizable substance is a compound having a radically polymerizable functional group, and the radical polymerizable functional group is preferably a vinyl group, an acryloyl group, or a methacryloyl group. Of these, compounds having an acryloyl group and / or a methacryloyl group are more preferable.

As the radical polymerizable substance, a compound described later can be used in either a monomer or an oligomer state, or a monomer and an oligomer can be used in combination.

Examples of the radical polymerizable substance include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, tetramethylolmethane tetra (meth) (Meth) acryloyloxypropane, 2,2-bis [4 - ((meth) acryloxymethoxy) phenyl] (Meth) acrylate, dicyclopentenyl (meth) acrylate, tricyclodecanyl (meth) acrylate, tris ((meth) acryloyloxyethyl) isocyanurate, urethane (Ethylene oxide) -modified diacrylate, 2-methacryloyloxyethyl acid phosphate, and the like can be given. These may be used alone or in combination.

The radical polymerizable material preferably has at least one partial structure selected from the group consisting of a dicyclopentane skeleton, a tricyclodecane skeleton, and a triazine ring. By using a radically polymerizable substance having such a partial structure, the cured product of the circuit connecting material is excellent in heat resistance.

Examples of the radical polymerizable material include polystyrene, polyethylene, polyvinyl butyral, polyvinylformal, polyimide, polyamide, polyester, polyvinyl chloride, polyphenylene oxide, urea resin, melamine resin, phenol resin, xylene A resin such as a resin, an epoxy resin, a polyisocyanate resin, or a phenoxy resin may be used. In addition, the polymer used as the radically polymerizable substance has at least one radically polymerizable functional group in the molecule.

When a polymer is contained as the radical polymerizable substance, it is preferable since it is good in handleability and stress relaxation at the time of curing is excellent, and it is more preferable that the polymer has a functional group such as a hydroxyl group to improve the adhesiveness. It is more preferable that each polymer is modified by a radical polymerizable functional group.

The weight average molecular weight of these polymers is preferably 1.0 x 10 ⁴ or more, and more preferably 1.0 x 10 ⁴ or more and 1.0 x 10 ⁶ or less from the viewpoint of mixing properties. The weight average molecular weight defined in the present application means measurement using a calibration curve with standard polystyrene by gel permeation chromatography (GPC) under the following conditions.

[GPC condition]

(Manufactured by Hitachi Kasei Kabushiki Kaisha), an eluent (product of Hitachi Chemical Co., Ltd.), and an eluent : Tetrahydrofuran, measurement temperature: 40 占 폚, flow rate: 1.75 ml / min, detector: L-3300RI (Hitachi Seisakusho, Kabushiki Kaisha)

The thiol compound is a compound having a thiol group and having the number of hydrogen atoms bonded to the carbon atom bonded with the thiol group of 0 or 1. Examples of the thiol compound include an aromatic thiol and a secondary thiol compound.

The aromatic thiol is a compound having a thiol group bonded to an aromatic ring. Examples of the aromatic thiol include allylbenzenethiol sulfonate, benzenethiol, o-ethoxybenzenethiol, p-ethoxybenzenethiol, 2-benzimidazolethiol, o Mercaptobenzoic acid, o-mercaptobenzoic acid methyl ester, 2-benzothiazole thiol, mercaptobenzoxazole, naphthalene thiol, toluene thiol, thiobisbenzene thiol, p-methoxy-toluene thiol and the like.

The secondary thiol compound is a compound having a secondary thiol group. Examples of the secondary thiol compound include secondary isothiol, 2,3-butanedithiol, hexa-5-en-3-thiol, secondary dodecanethiol , Secondary heptanethiol, secondary hexanethiol, secondary octadecanethiol, secondary octanethiol, 2-methyl-2-propanethiol, and the like. The secondary thiol compound has higher reactivity as a chain transfer agent than alcohols and is practically excellent.

As the secondary thiol compound, the compounds represented by the following formulas (1) to (5) are suitable.

The content of the thiol compound in the circuit connecting material is preferably 7 to 17 parts by mass, more preferably 9 to 12 parts by mass with respect to 100 parts by mass of the radical polymerizable material. If the content of the radical polymerizable substance is small, the effect of the high adhesive force in the rough pitch connection is hardly obtained, and if the content of the radical polymerizable substance is large, the crosslink density becomes low and the reliability of the circuit connecting material is deteriorated .

The molecular weight of the thiol compound is preferably 90 or more, more preferably 150 or more, and still more preferably 400 or more. The molecular weight of the thiol compound is preferably 5000 or less, more preferably 2,000 or less, and even more preferably 1,000 or less. When the molecular weight is less than 90, the compound reaches the boiling point of the compound by heating at the time of connection and evaporates, so that a sufficient amount of the thiol compound can not contribute to the reaction. On the other hand, when the molecular weight is larger than 5,000, the exclusion of the resin is deteriorated and the connection resistance tends to increase.

It is more preferable that the molecular weight of the thiol compound is 400 or more in terms of workability at the time of production and handleability of the product. When the molecular weight is less than 400, there is a tendency that the odor is strong when the material is compounded and when the product is handled, and the workability and handleability are lowered. On the other hand, when the molecular weight is 400 or more, odor is suppressed, and workability and handling properties are not impaired.

The thiol equivalent of the thiol compound is preferably 50 or more and 500 or less, more preferably 120 or more and 400 or less. When the thiol equivalent is less than 50, the crosslinking density is lowered, and the reliability of the resistance of the circuit connecting material tends to be lowered. On the other hand, if the thiol equivalent is 500 or less, the adhesion tends to be further improved.

The circuit connecting material according to the present embodiment may contain only a radical polymerization initiator, a radical polymerizable substance, and a thiol compound, but may further contain the following components, if necessary.

The circuit connecting material according to the present embodiment may further contain a compound having at least one aminosil structure in the molecule. When the circuit connecting material contains a compound having an aminosil structure, the storage stability of the circuit connecting material can be further improved.

The circuit connecting material according to the present embodiment may further contain a thermoplastic resin. Examples of the thermoplastic resin include a polyvinyl butyral resin, a polyvinyl formal resin, a polyamide resin, a polyester resin, a phenol resin, an epoxy resin, a phenoxy resin, a polystyrene resin, a xylene resin, a polyurethane resin, Can be used. The weight average molecular weight of these thermoplastic resins is preferably 1.0 x 10 ⁴ or more from the viewpoint of film formability and more preferably 1.0 x 10 ⁴ or more and less than 1.0 x 10 ⁶ from the viewpoint of mixing properties. The weight average molecular weight of the thermoplastic resin is measured in the same manner as the polymerization average molecular weight of the polymer that can be contained in the radical polymerizable substance.

As the thermoplastic resin, a hydroxyl group-containing resin (for example, a phenoxy resin) having a Tg (glass transition temperature) of 40 ° C or more and a weight average molecular weight of 1.0 x 10 ⁴ or more can be preferably used. The hydroxyl group-containing resin may be modified by an epoxy group-containing elastomer or a radical polymerizable functional group. Modified by a radical polymerizable functional group is preferable because heat resistance is improved.

The phenoxy resin can be obtained by reacting bifunctional phenols and epihalohydrins to a high molecular weight, or by allowing the bifunctional epoxy resin and the bifunctional phenol to react with each other to a high degree.

It is also preferable to use a polyester urethane resin as the thermoplastic resin. The incorporation of the polyester urethane resin tends to further improve the adhesion at the rough pitch connection.

The circuit connecting material according to the present embodiment may contain a filler, a softener, an accelerator, an antioxidant, a colorant, a flame retarder, a thixotropic agent, a coupling agent, a phenol resin, a melamine resin and an isocyanate.

As the coupling agent, a compound having at least one of a vinyl group, an acrylic group, an amino group, an epoxy group or an isocyanate group is preferable from the viewpoint of improvement in adhesiveness.

Further, when a filler is contained, connection reliability and the like can be improved, which is preferable. As the filler, those having a maximum diameter smaller than the particle diameter of the conductive particles described later can be used. The content of the filler is preferably in the range of 5 to 60% by volume based on the total volume of the circuit connecting material. When the amount is 60% by volume or more, the effect of improving the reliability is saturated.

The circuit connecting material according to the present embodiment can obtain the connection by the direct contact of the circuit electrodes opposed to each other at the time of connection even when the conductive particles are not contained. However, when the conductive particles are further contained, a more stable connection can be obtained .

Examples of the conductive particles include metal particles such as Au, Ag, Ni, Cu, and solder, and carbon. Further, the surface of transition metals such as Ni may be coated with precious metals such as Au. In order to obtain a sufficient usable time, it is preferable that the surface layer is not a transition metal such as Ni or Cu, but is made of a precious metal such as Au, Ag or a platinum group, and Au is more preferable. Further, it is also possible to form a conductive layer on the surface of non-conductive particles by coating the surface of non-conductive particles such as glass, ceramics or plastic with the above-mentioned conductive material or the like and to form the outermost layer by precious metals, In the case of metal particles, since the metal particles have deformability due to heating and pressing, the area of contact with the electrodes at the time of connection is increased, thereby improving reliability.

The blending amount of the conductive particles is appropriately set in accordance with the application, but is usually in the range of 0.1 to 30 parts by weight per 100 parts of the resin component in the circuit connecting material. It is more preferable to use 0.1 to 10 parts of skin to prevent short circuit of the adjacent circuit due to excess conductive particles.

In addition, when the circuit connecting material is divided into two or more layers and separated into a layer containing a curing agent and a layer containing conductive particles, the available time is improved.

The circuit connecting material according to the present embodiment may suitably contain a polymerization inhibitor such as hydroquinone, methyl ether hydroquinone or the like, if necessary.

Next, a connection structure and a manufacturing method thereof according to the present embodiment will be described.

1 is a schematic cross-sectional view showing an embodiment of a connection structure. 1 includes a first circuit member 20 having a first circuit board 21 and a first circuit electrode (first connection terminal) 22 formed on a main surface 21a thereof, A second circuit member 30 having a second circuit board 31 and a second circuit electrode (second connection terminal) 32 formed on the main surface 31a thereof; a first circuit member 30 And an adhesive layer 10 interposed between the second circuit members 30 and adhering them. The second circuit member 30 is disposed so as to face the first circuit member 20 so that the second circuit electrode 32 faces the first circuit electrode 22. [

The adhesive layer 10 is formed by interposing the circuit connecting material between the first circuit member 20 and the second circuit member 30, and pressing the circuit connecting material in this state. This embodiment shows an example in which the adhesive layer 10 is formed by using a circuit connecting material containing conductive particles. The adhesive layer 10 includes an insulating layer 11, an insulating layer 11 And conductive particles 7 dispersed in the conductive particles 7. The insulating layer 11 is a cured product derived from a component other than the conductive particles in the adhesive and formed by radical polymerization of a radical polymerizable substance.

The opposing first circuit electrodes 22 and second circuit electrodes 32 are electrically connected through conductive particles 7. On the other hand, the first circuit electrodes 22 and the second circuit electrodes 32 formed on the same circuit board are insulated.

The connection pitch of the first circuit electrode 22 and / or the second circuit electrode 32 may be 0.4 mm or more, or 0.45 mm or more. The upper limit of the connection pitch of the first circuit electrode 22 and / or the second circuit electrode 32 is not particularly limited, but may be, for example, 1.0 mm or less, or 0.9 mm or less.

The first circuit electrode 22 and / or the second circuit electrode 32 are formed so that at least a part thereof has a connection pitch (rough pitch) of 0.5 mm or more The first circuit member 20 and / or the second circuit member 30 are formed such that the first circuit electrode 22 and / or the second circuit electrode 32 are formed at a connection pitch of 0.5 mm or more Region).

The first circuit electrode 22 and the second circuit electrode 32 may be formed so that a part or all of the first circuit electrode 22 and the second circuit electrode 32 have L / S (Line / Space) of 4/6 to 9/1 And L / S may be 5/5 to 9/1. That is, the first circuit member 20 and / or the second circuit member 30 may be formed on the first circuit electrode 22 and / or the second circuit electrode 32 so that L / S is 4/6 to 9/1. May be formed. The total sum of the L / S of the first circuit electrode 22 and the L / S of the second circuit electrode 32 is 5/5 to 1 / 9. &Lt; / RTI >

Examples of the first circuit board 31 and the second circuit board 21 include semiconductor chips, chip parts such as resistor chips and capacitor chips, and substrates such as printed boards. Usually, the circuit member is provided with a plurality of connection terminals, but the connection terminals may be singular in some cases.

More specifically, substrates of inorganic materials such as semiconductors, glass and ceramics, plastic substrates or glass / epoxy substrates are used. Examples of the plastic substrate include a polyimide film, a polycarbonate film and a polyester film. The first circuit electrode and the second circuit electrode are formed of metal such as copper. In order to obtain better electrical connection, it is preferable that at least one surface of the first circuit electrode and the second circuit electrode is made of a metal selected from gold, silver, tin and platinum group metals. The surface layer may be selected from any of gold, silver, platinum group, and tin, and these may be used in combination. Further, a plurality of metals such as copper / nickel / gold may be combined to form a multilayer structure.

Either one of the first circuit member 20 and the second circuit member 30 may be a liquid crystal display panel having a glass substrate or a plastic substrate as a circuit substrate and having connection terminals formed of ITO or the like. One of the first circuit member 20 and the second circuit member 30 may be a flexible printed wiring board (FPC), a tape curie package (TCP) or a chip on film (COF) having a polyimide film as a circuit board, Or a semiconductor silicon chip having a semiconductor substrate as a circuit substrate. The connection structure is formed by appropriately combining these various circuit members as necessary.

It is preferable that the substrate on which the circuit electrode is formed is subjected to a heat treatment before the connection process by the circuit connecting material in order to exclude the influence on the connection by the volatile component due to the heating at the connection.

The connection structure 1 is constituted by connecting the first circuit member 20, the film circuit connecting material and the second circuit member 30 in this order to the first connection terminal 22 and the second connection terminal 32 Are superimposed on each other so as to be opposed to each other, and in this state, they are pressed or further heated. The pressure is not particularly limited as long as it does not cause damage to the adherend, but it is generally preferably from 0.1 to 10 MPa. The heating temperature is not particularly limited, but is preferably 100 to 200 占 폚. The pressing and heating are preferably performed in the range of 0.5 to 100 seconds, and it is possible to carry out the bonding even at 130 to 180 DEG C, 3 MPa, and 10 seconds of heating.

While the preferred embodiments of the present invention have been described above, the present invention is not limited to the above embodiments.

Example

Hereinafter, the present invention will be described more specifically based on examples and comparative examples, but the present invention is not limited to the following examples at all.

Synthesis of 1,3,5-tris (3-mercaptobutyloxyethyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H)

120 mmol (31.35 g) of 1,3,5-tris (2-hydroxyethyl) -1,3,5-triazine-2,4,6- (1H, 3H, 5H) 8.1 mmol (1.51 g) of p-toluenesulfonic acid · 1 hydrate (manufactured by Yutaka Chemical Industry Co., Ltd.) and 63 g of toluene were placed in a 100 ml eggplant-shaped flask, - equipped with a Dean-Stark unit and a cooling tube. The contents were heated at an oil bath temperature of 140 캜 with stirring and reacted for 4 hours. Thereafter, the reaction solution was allowed to cool, and the reaction solution was neutralized with 100 ml of a 10% aqueous solution of sodium hydrogencarbonate. Further, the reaction solution was washed three times with ion-exchanged water, and dehydrated and dried with anhydrous magnesium sulfate (manufactured by Yune Kagaku Co., Ltd.). Then, toluene was distilled off to obtain 1,3,5-tris (3-mercaptobutyloxyethyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) A compound having a thiol group represented by the above formula (1)). The obtained compound was a colorless transparent liquid having a high viscosity. This is hereinafter referred to as thiol A.

[Synthesis of pentaerythritol tetrakis (3-mercaptobutyrate)

, 60 mmol (8.17 g) of 2,2-bis (hydroxymethyl) 1,2-propanediol (pentaerythritol, manufactured by Goetgen Kagaku K.K.), 3-mercaptobutyric acid (manufactured by Yodogaku Chemical Co., 5.2 mmol (0.98 g) of p-toluenesulfonic acid monohydrate (manufactured by Junsei Kagaku Co., Ltd.) and 40 g of toluene were placed in a 100 ml eggplant-shaped flask, and a Dean-Stark apparatus and a cooling tube were mounted did. The contents were heated at an oil bath temperature of 140 캜 with stirring and reacted for 4 hours. Thereafter, the reaction solution was allowed to cool, and the reaction solution was neutralized with 100 ml of a 10% aqueous solution of sodium hydrogencarbonate. Further, the reaction solution was washed three times with ion-exchanged water and dehydrated and dried with anhydrous magnesium sulfate (manufactured by Yuka Chemical Co., Ltd.). Then, toluene was distilled off to obtain pentaerythritol tetrakis (3-mercaptobutyrate) (compound having a thiol group represented by the above formula (2)). The obtained compound was a colorless transparent liquid having a high viscosity. This is referred to as thiol B hereinafter.

[Example 1]

40 parts by mass of a polyester urethane resin (UR-8200, manufactured by Toyo Boseki Co., Ltd., 30% solution) in terms of nonvolatile content was used as the thermoplastic resin, a polyurethane resin (T-6075N, manufactured by Dai- A 20 mass% solution obtained by dissolving 10 mass parts of a 15 mass% solution obtained by dissolving in ethyl ketone in terms of nonvolatile matter, and an ethylene-vinyl acetate copolymer (EV40W, manufactured by Mitsui DuPont Polychemical Co., Ltd.) , 10 parts by mass as a radical polymerizable substance, 25 parts by mass of a 70% by mass solution of a urethane acrylate oligomer (UA5500T, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.) in toluene dissolved product in terms of a nonvolatile content, 10 parts by mass of dicyclopentadiene 5 parts by mass of diacrylate (DCP-A, manufactured by Toagosei Co., Ltd.), 5 parts by mass of isocyanuric acid EO-modified diacrylate (manufactured by Toagosei Co., , 3 parts by mass of 2-methacryloyloxyethyl acid phosphate (P-2M, manufactured by Kyoeisha Chemical Co., Ltd.) as a compound having a secondary thiol group, and 5 parts by mass of thiol A 4 parts by mass as a radical polymerization initiator, 4 parts by mass of 2,5-dimethyl-2,5-di (2-ethylhexanoyl) hexane (manufactured by Nippon Kayaku Co., 25O is a 50% solution, the blending amount of the product is 8 parts by mass), a mixture of di- (3-methylbenzoyl) peroxide and benzoyl (3-methylbenzoyl) peroxide and dibenzoyl peroxide 3 parts by mass (manufactured by Nippon Kayaku Co., Ltd.) (7.5 parts by mass of the product because of the 40% solution of BMT by Nippon Kayaku Co., Ltd.), followed by forming a nickel layer having a thickness of 0.2 탆 on the surface of polystyrene- , 6 parts by mass of conductive particles having an average particle size of 10 mu m formed by forming a gold layer having a thickness of 0.04 mu m outside the nickel layer, The. This mixed solution was applied onto a PET film by an applicator, and dried by hot air at 70 DEG C for 10 minutes to obtain a circuit connecting material having an adhesive layer thickness of 35 mu m. The compounding amount of the secondary-thiol group-containing compound in 100 parts by mass of the radically polymerizable substance (here, UA5500, DCP-A, M-215 and P-2M) in Example 1 was 10.5 parts by mass.

[Example 2]

A circuit connecting material was obtained in the same manner as in Example 1 except that the blending amount of thiol A (molecular weight: 567.7) was changed to 3 parts by mass. The compounding amount of the compound having a secondary thiol group in the 100 parts by mass of the radically polymerizable substance (here, UA5500, DCP-A, M-215 and P-2M) in Example 2 was 7.89 parts by mass.

[Example 3]

A circuit connecting material was obtained in the same manner as in Example 1 except that the blending amount of thiol A (molecular weight: 567.7) was changed to 6 parts by mass. The compounding amount of the compound having a secondary thiol group to the 100 parts by mass of the radically polymerizable substance (here, UA5500, DCP-A, M-215 and P-2M) in this Example 3 is 15.8 parts by mass.

[Example 4]

34 parts by mass of polyester urethane resin (UR8240) in terms of nonvolatile content, 8 parts by mass of dicyclopentadiene-type diacrylate (DCP-A), 8 parts by mass of isocyanuric acid EO-modified diacrylate Ltd., M-215, manufactured by Mitsubishi Chemical Corporation) was changed to 8 parts by mass, a circuit connecting material was obtained in the same manner as in Example 1. The compounding amount of the compound having a secondary thiol group to 9.0 parts by mass of 100 parts by mass of the radically polymerizable substance (here, UA5500, DCP-A, M-215 and P-2M) in Example 4 is 9.09 parts by mass.

[Example 5]

A circuit connecting material was obtained in the same manner as in Example 1 except that 3 parts by mass of thiol B (molecular weight: 544.77) was used instead of thiol A. The compounding amount of the compound having a secondary thiol group in 7.85 parts by mass based on 100 parts by mass of the radically polymerizable substance (here, UA5500, DCP-A, M-215 and P-2M)

[Example 6]

A circuit connecting material was obtained in the same manner as in Example 1 except that 6 parts by mass of thiol B (molecular weight: 544.77) was used instead of thiol A. The compounding amount of the secondary-thiol group-containing compound in the blend of 100 parts of the radically polymerizable substance (here UA5500, DCP-A, M-215 and P-2M) in Example 6 was 15.8 parts by mass.

[Comparative Example 1]

A circuit connecting material was obtained in the same manner as in Example 1 except that the blending amount of thiol A (molecular weight: 567.7) was changed to 2 parts by mass. The compounding amount of the compound having a secondary thiol group was 5.26 parts by mass based on 100 parts by mass of the radically polymerizable substance (here, UA5500, DCP-A, M-215 and P-2M) in Comparative Example 1.

[Comparative Example 2]

A circuit connecting material was obtained in the same manner as in Example 1 except that the blending amount of thiol A (molecular weight 567.7) was changed to 8 parts by mass. The compounding amount of the secondary-thiol group-containing compound to the 100 parts by mass of the radically polymerizable substance (here, UA5500, DCP-A, M-215 and P-2M) in Comparative Example 1 was 21.1 parts by mass.

[Comparative Example 3]

A circuit connecting material was obtained in the same manner as in Example 4 except that the blending amount of thiol A (molecular weight: 567.7) was changed to 2 parts by mass. The compounding amount of the compound having a secondary thiol group was 4.55 parts by mass based on 100 parts by mass of the radically polymerizable substance (here, UA5500, DCP-A, M-215 and P-2M) in Comparative Example 3.

[Comparative Example 4]

A circuit connecting material was obtained in the same manner as in Example 4 except that the blending amount of thiol A (molecular weight 567.7) was changed to 8 parts by mass. The compounding amount of the compound having a secondary thiol group in 18 parts by mass of 100 parts by mass of the radically polymerizable substance (here, UA5500, DCP-A, M-215 and P-2M) in Comparative Example 4 was 18.2 parts by mass.

[Comparative Example 5]

A circuit connecting material was obtained in the same manner as in Example 4 except that 8 parts by mass of thiol B (molecular weight: 544.77) was used instead of thiol A. The compounding amount of the compound having a secondary thiol group was 18.2 parts by mass based on 100 parts by mass of the radically polymerizable substance (here, UA5500, DCP-A, M-215 and P-2M) in Comparative Example 5.

[Comparative Example 6]

A circuit connecting material was obtained in the same manner as in Example 1 except that 2 parts by mass of thiol B (molecular weight: 544.77) was used instead of thiol A. The compounding amount of the compound having a secondary thiol group was 5.26 parts by mass based on 100 parts by mass of the radically polymerizable substance (here, UA5500, DCP-A, M-215 and P-2M) in Comparative Example 6.

Tables 1 and 2 show the compositions of the circuit connecting materials of Examples and Comparative Examples.

[Fabrication of connection structure (connection of COF and PWB)]

Using the respective circuit connecting materials of Examples 1 to 6 and Comparative Examples 1 to 6, a copper circuit having a line width of 250 mu m, a pitch of 500 mu m and a thickness of 8 mu m formed directly on polyimide having a thickness of 38 mu m, (COF-TEG) having 0.2 占 퐉 tin-plated flexible circuit board and a copper circuit having a line width of 250 占 퐉, a pitch of 500 占 퐉 and a thickness of 35 占 퐉, The wiring board (PWB-TEG) was connected at a temperature of 130 DEG C - 2 MPa - 10 seconds and a width of 2.0 mm. At this time, after attaching the adhesive surface of the circuit connecting material on the glass epoxy multilayer printed wiring board, the adhesive was heated and pressed at 70 DEG C and 1 MPa for 2 seconds, and then the PET film was peeled and connected to the COF-TEG.

[Measurement of Adhesion]

The adhesive strength at the time of peeling at 90 deg. Was measured at a peeling rate of 50 mm / min with respect to the produced connection structure. A was evaluated as A when the adhesive force was 12 N / cm or more, and B was evaluated when the adhesive strength was less than 12 N / cm. The obtained results are shown in Tables 3 and 4.

[Measurement of connection resistance]

After connection of the circuit, the initial resistance value between the adjacent circuits of the FPC-PWB including the connection portion was measured by a multimeter. Subsequently, the connection structure was left for 5 days in an environment of a temperature of 40 DEG C and a humidity of 60% The resistance value was measured by a multimeter. The resistance value was measured as the mean value and the maximum value of the resistance value of 37 points between adjacent circuits. The connection reliability after the high-temperature and high-humidity test at 85 캜 and 85% RH for 500 hours was evaluated based on the case where the rate of change of the maximum value was within three times of A and the case of B exceeding three times. Also, the smaller the rate of change of the maximum value, the better the connection reliability. The obtained results are shown in Tables 3 and 4.

As shown in Tables 3 and 4, in Examples 1 to 6, it was possible to achieve both a high adhesive force and a good connection reliability even in a rough pitch connection. On the other hand, in Comparative Examples 1, 3, and 6, sufficient adhesion was not obtained at the time of rough pitch connection. In Comparative Examples 4 and 5, although a high adhesive force was obtained, the connection resistance after the high temperature and high humidity treatment deteriorated, and sufficient connection reliability was not obtained.

The results of Examples and Comparative Examples at fine pitch connection are shown below as reference data.

[Fabrication of fine pitch connection structure (connection of COF and PWB)]

Using the respective circuit connecting materials of Examples 1 to 6 and Comparative Examples 1 to 6, a copper circuit having a line width of 100 mu m, a pitch of 200 mu m, and a thickness of 8 mu m formed directly on polyimide having a thickness of 38 mu m, (COF-TEG) having 0.2 μm of tin plating and a copper circuit having a line width of 100 μm, a pitch of 200 μm and a thickness of 35 μm was formed on the surface of the copper foil. The copper surface was coated with a glass epoxy multilayer printed The wiring board (PWB-TEG) was connected at a temperature of 130 DEG C - 2 MPa - 10 seconds and a width of 2.0 mm. At this time, the adhesive surface of the circuit connecting material was attached on the glass epoxy multilayer printed wiring board, and then heated and pressed at 70 DEG C for 1 second at 2 MPa for connection, and then the PET film was peeled and connected to the COF-TEG.

The adhesive force and the connection resistance were measured for the fine pitch connection structure manufactured as described above. The obtained results are shown in Tables 5 and 6.

At the fine pitch, all of Examples 1 to 6 exhibited good adhesion, but in connection reliability, a rise in resistance occurred. In Comparative Example 1, 3, 4 and 6, in which the ratio of secondary thiol to 100 parts by mass of the radical polymerizable substance was less than 7, stable connection reliability was obtained.

As described above, at the fine pitch, no great difference was observed in the adhesive force between the examples and the comparative examples. It is considered that the present invention increases the usability in a rough pitch connection circuit.

1 ... connection structure
7 ... conductive particles
10 ... adhesive layer
11 ... insulating layer
20 ... first circuit member
21 ... first circuit substrate
22 ... first circuit electrode (first connection terminal)
30 ... second circuit member
31 ... second circuit substrate
32 ... second circuit electrode (second connection terminal)

Claims

The first circuit member having the first circuit electrode formed on the main surface of the first substrate and the second circuit member having the second circuit electrode formed on the main surface of the second substrate are arranged such that the first circuit electrode and the second circuit electrode are opposed And is a circuit connecting material to be connected in a state of being connected,
A radical polymerization initiator, a radical polymerizable substance, and a thiol compound having a thiol group and having 1 or 0 hydrogen atoms bonded to a carbon atom bonded to the thiol group,
Wherein the content of the thiol compound is 7 to 17 parts by mass relative to 100 parts by mass of the radical polymerizable material.

The circuit connecting material according to claim 1, wherein the thiol compound has a molecular weight of 400 or more.

The method according to claim 1 or 2, wherein the first circuit member or the second circuit member is arranged on the main surface of the first substrate or the second substrate at a connection pitch of 0.5 mm or more, And a region where a circuit electrode is formed.

A first circuit member having a first circuit electrode formed on a main surface of the first substrate,
A second circuit member having a second circuit electrode formed on the main surface of the second substrate and the second circuit electrode and the first circuit electrode facing each other,
And an adhesive layer formed between the first circuit member and the second circuit member and electrically connecting the first circuit member and the second circuit member,
Wherein the adhesive layer is formed by heating and pressing the circuit connecting material according to any one of claims 1 to 3 interposed between the first circuit member and the second circuit member.

5. The semiconductor device according to claim 4, wherein the first circuit member or the second circuit member is formed on the main surface of the first substrate or the second substrate such that the first circuit electrode or the second circuit electrode is formed at a connection pitch of 0.5 mm or more Region.

A first circuit member having a first circuit electrode formed on a main surface of the first substrate,
A second circuit member having a second circuit electrode formed on a main surface of the second substrate,
A circuit connecting material according to any one of claims 1 to 3,
And a step of electrically connecting the first circuit electrode and the second circuit electrode by heating and pressing in a state in which the first circuit electrode and the second circuit electrode are disposed so as to face each other through the circuit connecting material , And a method for manufacturing a connection structure.

7. The semiconductor device according to claim 6, wherein the first circuit member or the second circuit member is formed on the main surface of the first substrate or the second substrate such that the first circuit electrode or the second circuit electrode Region, wherein the method comprises the steps of:

A radical polymerization initiator, a radical polymerizable substance, and a thiol compound having a thiol group and having 1 or 0 hydrogen atoms bonded to a carbon atom bonded to the thiol group,
Wherein the content of the thiol compound is 7 to 17 parts by mass relative to 100 parts by mass of the radical polymerizable material,
The first circuit member having the first circuit electrode formed on the main surface of the first substrate and the second circuit member having the second circuit electrode formed on the main surface of the second substrate are arranged such that the first circuit electrode and the second circuit electrode are opposed To connect in a state of being used.

The use according to claim 8, wherein the thiol compound has a molecular weight of 400 or more.

10. The semiconductor device according to claim 8 or 9, wherein the first circuit member or the second circuit member is formed on the main surface of the first substrate or the second substrate with a connection pitch of 0.5 mm or more, And a region where the circuit electrode is formed.