JP2007009183A - Polyhydroxypolyether resin and resin composition using the same, and adhesive for bonding circuit member and circuit board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyhydroxypolyether resin which can form a resin composition having good solubility in a solvent, good film formability and good heat resistance and capable of maintaining high adhesion even after being exposed under the condition of high-temperature and high-humidity, when used as an adhesive. <P>SOLUTION: The polyhydroxypolyether resin comprises a chemical structure represented by general formula (I), wherein R<SP>1</SP>, R<SP>2</SP>, R<SP>3</SP>, R<SP>4</SP>, R<SP>5</SP>, R<SP>6</SP>, R<SP>7</SP>, and R<SP>8</SP>each independently indicates a hydrogen atom, a 1-6C straight-chain or branched alkyl group, a 1-6C hydroxyalkyl group or a halogen atom. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a polyhydroxy polyether resin, a resin composition using the same, an adhesive for connecting circuit members, and a circuit board.

  In recent years, the demand for lead-free semiconductor packages is increasing due to consideration for the global environment. Since the melting point of solder that does not contain lead is higher than that of Sn / Pb eutectic solder that has been used in the past, the reflow processing temperature increases from 240 ° C. to 260 ° C. with the lead-free process. For this reason, the further improvement of heat resistance is calculated | required with respect to the organic material which comprises a semiconductor package.

  There is also an increasing demand for thinner and smaller semiconductor packages. Therefore, as a semiconductor chip mounting method, instead of the conventional wire bonding method using metal wires, bump electrodes called bumps are formed on the chip electrodes, and the substrate electrodes and chip electrodes are directly connected via the bumps. The flip chip connection method is attracting attention.

  Known flip-chip connection methods include a method using solder bumps, a method using gold bumps and a conductive adhesive, a thermocompression bonding method, and an ultrasonic method. In these methods, there is a problem that the connection reliability is lowered due to the thermal stress derived from the difference in thermal expansion coefficient between the chip and the substrate being concentrated on the connection portion. In order to prevent such a decrease in connection reliability, an underfill that fills the gap between the chip and the substrate is generally formed of a resin. Since thermal stress is alleviated by dispersion in the underfill, connection reliability can be improved.

  As a method for forming the underfill, a method of injecting a liquid resin into the gap between the chip and the substrate after connecting the chip and the substrate, or supplying an underfill resin on the substrate or the chip in advance, There is a method of completing underfill formation in the step of connecting the substrates.

  In the method of injecting a liquid resin, it takes a long time to fill the resin in a narrow gap of 100 μm or less, which tends to lead to a decrease in productivity. On the other hand, as a method of supplying a resin to be an underfill in advance, a method using a paste-like resin such as NCP (Non Conductive Paste) (see Patent Document 1) and a film-like resin such as NCF (Non Conductive Film) are used. The method using the paste-like resin, which is divided into methods (see Patent Document 2), has problems such as remaining voids and contamination of the back surface of the chip when a thin chip is used. According to the method using a film-like resin, handling is easy and the production process can be simplified.

  As a resin for forming the underfill, a resin composition containing a three-dimensional crosslinkable resin component such as an epoxy resin is widely used. In particular, in the case of a method using a film-like resin, a resin composition in which a good film-forming property is secured by combining a resin capable of forming a film alone with a three-dimensional crosslinkable resin is used.

  As the resin combined with the three-dimensional crosslinkable resin, a thermoplastic resin such as a phenoxy resin or a polyimide resin is mainly used. In addition, the present applicant previously invented a polyhydroxy polyether resin having a chemical structure represented by the following general formula (B) (see Patent Document 3). In this polyhydroxy polyether resin, a rigid biphenyl skeleton is introduced in order to enhance intermolecular interaction and improve heat resistance.

  By the way, a method of dispersing liquid rubber, cross-linked rubber, and core-shell type rubber particles in a resin composition containing an epoxy resin is known for the purpose of relaxing and strengthening the internal stress of the epoxy resin (non-patented). Reference 1). However, it is known that a cured product in which rubber is dispersed has a lower glass transition temperature than when no rubber is used, which causes a decrease in reliability in a field where high heat resistance is required.

  In order to improve the glass transition temperature in the rubber dispersion system, a method of increasing the crosslinking density of the epoxy resin is conceivable. However, in this case, there is a problem in that the effect of rubber dispersion is reduced, the cured product becomes brittle and the water absorption increases, leading to a decrease in reliability.

On the other hand, as a method of toughening an epoxy resin without lowering the glass transition temperature, a high heat-resistant thermoplastic resin called engineering plus chip such as polyethersulfone or polyetherimide is blended with the epoxy resin, and the cured product is mixed. A method of forming a phase separation structure is known. However, in this case, since the thermoplastic resin component having a small content becomes a matrix (continuous phase), there is a possibility that the original electrical characteristics of the epoxy resin may be lost (see Non-Patent Document 2).
JP 2001-127215 A JP 2004-315688 A International Publication No. 01/059007 Pamphlet Satoshi Kishi and three others, “Toughening the epoxy resin and improving the peel adhesion strength with a polymer fine particle modifier”, Journal of the Adhesion Society of Japan, 2004, vol. 40, no. 5, p. 177-183 Satoshi Murakami and one other, "Epoxy resin blend", Journal of the Adhesion Society of Japan, 2001, vol. 37, no. 11, p. 459-468

  Conventionally, when a chip and a substrate are connected via an adhesive as an underfill, there has been a problem that the adhesive force at the interface between the adhesive and the chip or the substrate is lowered under high temperature and high humidity.

  Conventionally, improvement in connection reliability under high temperature and high humidity has also been demanded. For example, when a thermal stress derived from a difference in thermal expansion coefficient between the chip and the substrate occurs in the connection portion under the temperature cycle test condition, the connection resistance may increase or the adhesive may peel off. In addition, since the semiconductor package performs reflow treatment after absorbing moisture under high-temperature and high-humidity conditions, the moisture absorbed in the adhesive may rapidly expand, resulting in increased connection resistance and peeling of the adhesive. It was.

  In addition, since a commonly used phenoxy resin has a low glass transition temperature of 100 ° C. or less, which is a measure of heat resistance, it is difficult to obtain an adhesive having high heat resistance using this resin. On the other hand, the glass transition temperature of the polyimide resin is generally 200 ° C. or higher, and the polyhydroxy polyether resin has high heat resistance. However, these resins have a problem of relatively low solubility. If the solubility is low, when a varnish in which an adhesive is dissolved in an organic solvent is prepared, a workability is deteriorated by forming a film on the surface of the varnish or causing stringing of the varnish.

  The present invention has been made in view of the above problems, has good solubility in a solvent, has good film-forming properties and high heat resistance, and has a high temperature and high humidity environment when used as an adhesive. An object of the present invention is to provide a polyhydroxy polyether resin that makes it possible to obtain a resin composition that can maintain a high adhesive force even after being exposed to the bottom.

  In addition, the present invention provides a resin composition that has good film-forming properties and high heat resistance, and can maintain high adhesive force even after being exposed to a high temperature and high humidity environment when used as an adhesive. The purpose is to provide goods.

  Another object of the present invention is to provide an adhesive for connecting circuit members that exhibits high heat resistance and high adhesive strength after being exposed to a high-temperature and high-humidity environment, and that can improve connection reliability. To do.

  Furthermore, an object of the present invention is to provide a circuit board in which circuit members are bonded to each other with high adhesive force and connection reliability is improved.

  The present invention relates to the following general formula (I):

で表される化学構造を含むポリヒドロキシポリエーテル樹脂である。式（Ｉ）中、Ｒ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７及びＲ^８はそれぞれ独立に水素原子、炭素数１〜６の直鎖若しくは分岐アルキル基、炭素数１〜６のヒドロキシアルキル基又はハロゲン原子を示す。

It is polyhydroxy polyether resin containing the chemical structure represented by these. In formula (I), R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are each independently a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, carbon The hydroxyalkyl group or halogen atom of number 1-6 is shown.

  The polyhydroxy polyether resin has the following general formula (II):

で表される化学構造を含むことが好ましい。式（ＩＩ）中、Ｒ^ａ、Ｒ^ｂ、Ｒ^ｃ及びＲ^ｄはそれぞれ独立に水素原子、炭素数１〜６の直鎖若しくは分岐アルキル基、炭素数６の環状アルキル基、置換基を有していてもよいアリール基、置換基を有していてもよいアラルキル基又はハロゲン原子を示す。

It is preferable that the chemical structure represented by these is included. In formula (II), R ^a , R ^b , R ^c and R ^d each independently have a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a cyclic alkyl group having 6 carbon atoms, or a substituent. An aryl group which may be substituted, an aralkyl group which may have a substituent, or a halogen atom.

  Alternatively, the present invention provides the following general formula (III):

で表される化学構造を含むポリヒドロキシポリエーテル樹脂である。式（ＩＩＩ）中、Ｒ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５、Ｒ^６、Ｒ^７及びＲ^８はそれぞれ独立に水素原子、炭素数１〜６の直鎖若しくは分岐アルキル基、炭素数１〜６のヒドロキシアルキル基又はハロゲン原子を示し、Ｒ^ａ、Ｒ^ｂ、Ｒ^ｃ及びＲ^ｄはそれぞれ独立に水素原子、炭素数１〜６の直鎖若しくは分岐アルキル基、炭素数６の環状アルキル基、置換基を有していてもよいアリール基、置換基を有していてもよいアラルキル基又はハロゲン原子を示し、ｎは正の整数を示す。

It is polyhydroxy polyether resin containing the chemical structure represented by these. In formula (III), R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are each independently a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, carbon Represents a hydroxyalkyl group of 1 to 6 or a halogen atom, and R ^a , R ^b , R ^c and R ^d each independently represent a hydrogen atom, a linear or branched alkyl group of 1 to 6 carbon atoms, and a cyclic of 6 carbon atoms. An alkyl group, an aryl group which may have a substituent, an aralkyl group which may have a substituent, or a halogen atom; and n represents a positive integer.

  The polyhydroxy polyether resin according to the present invention has good solubility. In addition, by combining this resin with other components such as a three-dimensional crosslinkable resin component, it has good film-forming properties and high heat resistance, and is exposed to a high temperature and high humidity environment when used as an adhesive. A resin composition capable of maintaining a high adhesive force even after being applied is obtained.

  The resin composition according to the present invention contains any of the above polyhydroxypolyether resins and a three-dimensional crosslinkable resin component.

  The resin composition according to the present invention has good film formability and high heat resistance, and can maintain high adhesive force even after being exposed to a high temperature and high humidity environment when used as an adhesive. Is possible.

  The present invention also includes a circuit board and a circuit electrode formed on the main surface of the circuit board, and a pair of circuit members arranged so that the circuit electrodes are arranged to face each other. It is an adhesive for connecting a circuit member made of the resin composition according to the present invention, which is used for bonding so that the circuit electrodes are electrically connected to each other.

  The adhesive for connecting circuit members according to the present invention exhibits high heat resistance and high adhesive strength after being exposed to a high temperature and high humidity environment, and also exhibits high connection reliability.

  The present invention also includes a circuit board and a circuit electrode formed on the main surface of the circuit board, and a pair of circuit members arranged so that the circuit electrodes face each other. A pair of circuit members bonded to each other so that the circuit electrodes disposed opposite to each other are electrically connected to each other. It is a circuit board formed with the adhesive for circuit member connection which concerns on invention.

  The circuit board according to the present invention has high connection reliability while the circuit members are bonded to each other with high adhesive force.

  The polyhydroxy polyether resin according to the present invention has good solubility in a solvent, has good film-forming properties and high heat resistance, and is exposed to a high temperature and high humidity environment when used as an adhesive. It is possible to obtain a resin composition capable of maintaining a high adhesive force even after being applied.

  The resin composition according to the present invention has good film formability and high heat resistance, and can maintain high adhesive force even after being exposed to a high temperature and high humidity environment when used as an adhesive. It is.

  The adhesive for connecting circuit members according to the present invention exhibits high heat resistance and high adhesive strength after being exposed to a high temperature and high humidity environment, and also enables improvement in connection reliability.

  In the circuit board according to the present invention, circuit members are bonded to each other with high adhesive force, connection reliability is improved, and reflow resistance is also excellent.

  Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

  The polyhydroxy polyether resin according to the present embodiment is a polymer compound including a plurality of chemical structures having a sulfide bond represented by the general formula (I).

In the formula (I), R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are each independently a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, carbon The hydroxyalkyl group or halogen atom of number 1-6 is shown.

  Examples of the linear or branched alkyl group having 1 to 6 carbon atoms include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, t-butyl group, and n-pentyl group. And n-hexyl group. Among these, a methyl group, an ethyl group, an n-butyl group, and a t-butyl group are preferable. Examples of the hydroxyalkyl group having 1 to 6 carbon atoms include a hydroxymethyl group, a hydroxyethyl group, a hydroxypropyl group, a hydroxybutyl group, a hydroxypentyl group, and a hydroxyhexyl group. Among these, a hydroxymethyl group is preferable. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Among these, a fluorine atom is preferable.

  It is preferable that the polyhydroxy polyether resin further includes a chemical structure represented by the general formula (II). In this case, in order to obtain a stable solubility, the polyhydroxy polyether resin is composed of 4,4′-thiobisphenol compound and 4,4 ′-(9-fluorenylidene, as represented by the general formula (III). It is preferable to have a repeating unit in which) -diphenol compound is alternately bonded.

In the formulas (II) and (III), R ^a , R ^b , R ^c and R ^d are each independently a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a cyclic alkyl group having 6 carbon atoms, substituted The aryl group which may have a group, the aralkyl group which may have a substituent, or a halogen atom is shown.

Specific examples of the linear or branched alkyl group having 1 to 6 carbon atoms and halogen atom represented by R ^{a to} R ^d include the same as those described for R ^{1 to} R ⁸ . Examples of the aryl group include a phenyl group, a naphthyl group, and an anthranyl group. These may have a substituent. Aralkyl groups include benzyl and phenethyl groups. Of these, R ^{a to} R ^d are particularly preferably ^a hydrogen atom, a methyl group, or a t-butyl group.

  The terminal portion of the polyhydroxy polyether resin is typically a glycidyl group or a phenolic hydroxyl group. In this case, both terminal portions of the polyhydroxy polyether resin are represented by the following general formulas (1) and (2), for example.

In the formula (1), X ¹ is a hydrogen atom or a group represented by the following general formula (a), (b) or (d). Wherein (2), ^{X 2} is a hydrogen atom, or the following general formula (b), a group represented by (c) or (e).

Typically, when X ¹ in formula (1) is a radical of hydrogen atom or formula (a), X ² in formula (2) is a group of formula (b) or formula (c), When X ¹ in formula (1) is a group of formula (b) or formula (d), X ² in formula (2) is a hydrogen atom or a group of formula (e).

  Reaction accelerators and curing agents such as imidazoles may be added to the glycidyl groups in the formulas (a), (b) and (e).

  The weight average molecular weight in terms of polystyrene of the polyhydroxy polyether resin is preferably 5,000 to 1,000,000, and more preferably 10,000 to 450,000. If the weight average molecular weight is less than 5,000, the film formability tends to be reduced and the film tends to be brittle. If the weight average molecular weight is less than 10,000, the tackiness of the adhesive tends to increase and the handleability of the film tends to be lowered. Moreover, when a weight average molecular weight exceeds 450,000, there exists a tendency for fluidity | liquidity to fall, and when it exceeds 1 million, there exists a tendency for solubility to fall.

  As will be understood by those skilled in the art, the polyhydroxy polyether resin can be synthesized by a known method such as solution polymerization or melt mixing. A solution polymerization method that can easily achieve an appropriate molecular weight is preferred.

  When a polyhydroxy polyether resin is synthesized by a solution polymerization method, for example, a diglycidyl ether of a 4,4′-thiobisphenol compound and a 4,4 ′-(9-fluorenylidene) -diphenol compound, or 4,4 ′ -A polymerization reaction between the thiobisphenol compound and the 4,4 '-(9-fluorenylidene) -diphenol compound is carried out in solution. As a reaction solvent, a solvent in which these compounds are dissolved, for example, N-methylpyrrolidone is used. The reaction proceeds efficiently by adding a base such as sodium hydroxide or potassium carbonate to the reaction solution. Generally, polyhydroxy polyether resin is obtained by reaction for 1 to 5 hours at 100-130 degreeC.

  The resin composition according to this embodiment contains the polyhydroxy polyether resin and a three-dimensional crosslinkable resin component. This resin composition is particularly preferably used as an adhesive for connecting a circuit member used for connecting circuit members to obtain a circuit board.

  The three-dimensional crosslinkable resin component contains a three-dimensional crosslinkable resin and, if necessary, a curing agent and a curing accelerator. By the crosslinking reaction of the three-dimensional crosslinkable resin component, the resin composition is cured to form a cured product.

  The three-dimensional crosslinkable resin is a resin that forms a three-dimensional crosslinked structure by a crosslinking reaction such as a radical reaction that proceeds by heating, light, or the like. From the viewpoint of heat resistance, a thermosetting resin that is crosslinked by heating is desirable.

  Specific examples of thermosetting resins include epoxy resins, bismaleimide triazine resins, polyimide resins, cyanoacrylate resins, phenol resins, unsaturated polyester resins, melamine resins, urea resins, polyisocyanate resins, furan resins, resorcinol resins, Examples include xylene resins, benzoguanamine resins, diallyl phthalate resins, siloxane-modified epoxy resins, siloxane-modified polyamideimide resins, and benzocyclobutene resins. Alternatively, unvulcanized (uncrosslinked) natural rubber, nitrile rubber, butadiene rubber, silicone rubber, isobutylene rubber and the like can be used as the thermosetting resin.

  These resins may be a copolymer system or a mixed system, and are used together with a curing agent. Among these, epoxy resins are preferable from the viewpoints of high versatility and easy availability of high-purity products having a low concentration of chlorine ions, hydrolyzable chlorine, and the like, and prevention of migration and corrosion of circuit wiring.

  The epoxy resin is preferably bifunctional or higher. Specifically, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, phenol aralkyl type epoxy resin Dicyclopentadiene type epoxy resin and the like are preferably used. These may be used alone or in combination of two or more.

  The epoxy resin may be liquid or solid at 25 ° C.

  As the curing agent for the epoxy resin, imidazoles, polyhydric phenols, acid anhydrides, amines, hydrazides, polymercaptan, Lewis acid-amine complexes, and the like can be used. From the viewpoint of storage stability and heat resistance of the cured product, the curing agent is preferably an imidazole, a polyhydric phenol, or an acid anhydride, and more preferably an imidazole or a polyhydric phenol. These may be used alone or in combination of two or more. When the curing agent is an imidazole, 2P4MHZ, 2PHZ, 2MA-OK (product name, manufactured by Shikoku Kasei Kogyo Co., Ltd.) is preferably used from the viewpoint of storage stability.

  A microcapsule-type latent curing agent in which a curing agent is coated with a polyurethane-based or polyester-based polymer substance to form a microcapsule is particularly preferable because it has excellent storage stability and extends the pot life.

  In the resin composition, the mass ratio of the polyhydroxy polyether resin and the three-dimensional crosslinkable resin component is preferably 1/99 to 99/1 (the total of both is 100), more preferably 10/90 to 90 /. 10. When the mass ratio is less than 1/99, it tends to be difficult to exhibit film formability and stress absorption ability, and when it exceeds 99/1, heat resistance tends to be lowered.

  The resin composition may contain a rubber component such as acrylic rubber for the purpose of reducing the elastic modulus of the cured product. In order to make film formation easier, you may contain other thermoplastic resins, such as a phenoxy resin. However, the blending amount of these components should be within a range where the heat resistance of the resin composition is not significantly impaired.

  The resin composition preferably contains a filler such as an insulating inorganic filler or whisker. Thereby, the thermal expansion coefficient and water absorption rate of hardened | cured material are reduced more.

  As the insulating inorganic filler, for example, a filler containing at least one selected from the group consisting of glass, silica, alumina, titanium oxide, carbon black, mica and boron nitride is used. Among these, glass, silica, alumina, and titanium oxide are preferable, and glass, silica, and alumina are more preferable. As the whisker, for example, one containing at least one selected from the group consisting of aluminum borate, aluminum titanate, zinc oxide, calcium silicate, magnesium sulfate and boron nitride is used. These fillers are used alone or in combination of two or more.

  The shape of the filler is not particularly limited, but in the case of a spherical shape, the particle size is preferably 10 μm or less in order to prevent the filler from being trapped between the electrodes and inhibiting electrical connection. Moreover, when using together with electroconductive particle, it is preferable that the average particle diameter of a filler is smaller than the average particle diameter of electroconductive particle.

  The blending amount of the filler is preferably 25 to 300 parts by weight and more preferably 50 to 200 parts by weight with respect to 100 parts by weight of the total amount of the polyhydroxy polyether resin and the three-dimensional crosslinkable resin component. If the amount is less than 25 parts by weight, the effect of reducing the coefficient of thermal expansion tends to decrease. If the amount exceeds 300 parts by weight, the resin composition before curing becomes brittle, and the handleability of the film tends to decrease.

  For the purpose of improving the adhesive strength of the filler, a silane-based or titanium-based coupling agent may be included in the resin composition. It is preferable that the compounding quantity of a coupling agent is 0.1-10 weight part with respect to 100 weight part of fillers.

  By the way, it is known that it is effective to introduce into the resin composition a sulfur atom that easily binds to Au in order to improve the adhesion to difficult-to-bond Au (Naoki Kumaki et al., 3 others) , "Study on improvement of adhesion to gold by phenolic disulfide", Network Polymer, 2005, Vol. 26, No. 4, p. 17-23). Therefore, in order to improve the adhesive force, it is expected that the adhesive force is improved by introducing a functional group containing a sulfur atom or using a coupling agent containing a sulfur atom. However, according to the knowledge of the present inventors, actually, there are many cases where the functional group or the coupling agent is decomposed and a sufficient effect is not exhibited.

  On the other hand, since the polyhydroxy polyether resin contains a sulfur atom in the molecular skeleton and is not decomposable, it is considered that the adhesion is remarkably improved by coordination with Au. Further, the diphenyl sulfide skeleton has higher flexibility than the rigid biphenyl skeleton, and according to the polyhydroxy polyether resin according to the present embodiment, the polyhydroxy polyether resin represented by the above general formula (B) was used. The advantage that the film is less likely to become brittle than that is also obtained. Furthermore, in the diphenyl sulfide skeleton, conjugation between two phenyl groups is hindered by a sulfur atom, and therefore, it is considered that the intermolecular interaction is weaker than that of the biphenyl skeleton. As a result, it is considered that the solubility is further improved.

  Conductive particles may be dispersed in the resin composition. Thereby, when the resin composition is used as an adhesive for connecting a circuit member, it becomes possible to easily absorb variations in the height of circuit electrodes such as chip bumps and substrate electrodes. As the conductive particles, metal particles, cores made of spherical polymer resin such as polystyrene, and coated particles having a conductive layer formed so as to cover them are preferably used. The metal particles include, for example, at least one metal selected from the group consisting of Au, Ni, Ag, Cu, and solder as a main component. A thin film such as Au or Pd may be formed by plating or vapor deposition on the surface of particles containing these metals as main components. The conductive layer of the coated particles is formed from Ni, Cu, Au, solder or the like.

  The particle size of the conductive particles needs to be smaller than the minimum distance between the circuit electrodes, and when there is a variation in the height of the circuit electrodes, it is preferable that the particle size be larger than the variation. More specifically, the particle diameter of the conductive particles is preferably 1 to 10 μm. The amount of conductive particles in the resin composition is preferably 0.1 to 30% by volume, more preferably 0.2 to 20% by volume based on the total amount of the resin composition.

  The resin composition according to this embodiment is particularly useful when used as an adhesive in the form of a film. The resin composition is dissolved or dispersed in an organic solvent to prepare a varnish, and this is applied to a releasable support substrate, and the resin composition is formed into a film by removing the solvent below the curing agent activation temperature. can do. The solvent used at this time is preferably an aromatic hydrocarbon solvent, an oxygen atom-containing organic solvent, or a mixed solvent thereof.

  Examples of the aromatic hydrocarbon solvent include benzene, toluene, xylene, and ethylbenzene.

  Examples of the oxygen atom-containing organic solvent containing an oxygen atom in the molecule include ester solvents such as ethyl acetate, ketone solvents such as acetone, methyl ethyl ketone and cyclohexanone, ether solvents such as tetrahydrofuran and dioxane, N-methylpyrrolidone, N, Examples thereof include amide solvents such as N-dimethylacetamide, and dimethyl sulfoxide.

  FIG. 1 is a sectional view showing an embodiment of a circuit board according to the present invention. A circuit board 1 shown in FIG. 1 has a configuration in which a pair of opposing circuit members 20 and 30 are bonded and connected via a connecting portion 10. The circuit member 20 has a circuit board 21 and a plurality of circuit electrodes 22 formed on the main surface thereof, and the circuit member 30 has a circuit board 31 and a plurality of circuit electrodes 32 formed on the main surface thereof. . The circuit members 20 and 30 are disposed such that the circuit electrode 22 and the circuit electrode 32 are disposed to face each other. The circuit electrodes arranged opposite to each other are electrically connected.

  The connection part 10 is formed using the resin composition according to the embodiment as an adhesive for connecting circuit members. That is, the connection part 10 consists of the hardened | cured material of the adhesive agent for a circuit member connection. In more detail, the connection part 10 is comprised from the matrix 11 formed from the polyhydroxy polyether resin, the three-dimensional crosslinkable resin component, etc., and the electroconductive particle 12 disperse | distributed in the matrix 11. FIG.

  As the circuit boards 21 and 31, insulating boards such as glass epoxy, polyimide, polyester, and ceramic are used.

  When the circuit boards 21 and 31 are insulating substrates, the circuit electrodes 22 and 32 are formed by etching, removing a part of a metal layer such as copper formed on the surface of the insulating substrate, plating, or conductive material. It is formed by the method by printing. In this case, the circuit electrodes 22 and 32 preferably include at least one metal selected from the group consisting of silver, copper, nickel, indium, palladium, tin, lead, and bismuth. The circuit electrodes 22 and 32 may have a structure in which a plurality of metal layers having different compositions are laminated.

  Or the semiconductor chip in which the circuit electrode was formed can also be used as one or both circuit members. In this case, the adhesive for connecting a circuit member can function as an underfill material in the flip chip connection method. The circuit electrode at this time is usually made of aluminum, but a metal layer such as gold, silver, copper, nickel, indium, palladium, tin, lead, or bismuth may be formed on the surface thereof by plating.

  The circuit electrode of the semiconductor chip may have a protruding electrode called a bump. As bumps, stud bumps formed using metal wires, or in some cases heating and pressurizing while using ultrasonic waves together, fixing metal balls to semiconductor chip electrodes, and formed by plating and vapor deposition is there. Alternatively, the bumps may be formed by printing a conductive paste.

  The bump may be composed of a single metal such as gold, silver, copper, nickel, indium, palladium, tin, lead, bismuth, or may include a plurality of metal components. The structure by which the metal layer from which a composition differs was laminated | stacked may be sufficient.

  The circuit board 1 is, for example, a circuit member connection adhesive by heating and pressurizing a laminated body having a pair of circuit members 20 and 30 disposed opposite to each other and a circuit member connection adhesive interposed therebetween. It can obtain by a manufacturing method provided with the process of hardening | curing and forming the connection part 10. FIG.

  In this case, the position and area for supplying the circuit member connecting adhesive to the surfaces of the circuit members 20 and 30 are arbitrary, but it is preferable to supply at least a part of the circuit electrodes 22 and 32. When the adhesive for connecting circuit members is in the form of a film, the film cut into pieces may be attached in advance to the circuit member by heating and pressing.

  When the circuit member is a semiconductor chip, a film-like adhesive is attached to a semiconductor wafer with a roll laminator and then dicing to produce a semiconductor chip to which the film-like adhesive is attached. It can also be used in the process.

  When connecting the circuit electrodes, a method of pressurizing and heating the laminate and applying ultrasonic vibration to join the circuit electrodes to each other can be used.

  After the circuit member connecting adhesive is cured to some extent by pressurization and heating, the curing reaction may be further advanced by heating in an oven again.

  The resin composition according to the present embodiment can be used not only as an underfill material in a flip chip connection method, but also bonded and fixed to the substrate surface with the circuit forming surface of the semiconductor chip facing upward, and an electrode of the semiconductor chip with a gold wire or the like In the wire bonding method for electrically connecting the wiring pattern of the substrate and the substrate, it can also be used as an adhesive for bonding the chip and the substrate. Further, in a stacked package in which semiconductor chips are stacked in multiple stages, it can also be used as an adhesive for bonding and fixing semiconductor chips.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

Synthesis of polyhydroxy polyether resin Example 1
45 g of 4,4 ′-(9-fluorenylidene) -diphenol (manufactured by Sigma Aldrich Japan Co., Ltd.) and 50 g of 2,2′-dimethyl-5,5′-bis (t-butyl) -diphenol sulfide diglycidyl ether N-methylpyrrolidone (1000 mL) in a 3000 mL three-necked flask equipped with a Teflon stirring rod connected to a Dimroth condenser, calcium chloride tube, and stirring motor (product name: GK-4292, manufactured by Tohto Kasei Co., Ltd.) To give a reaction solution. To the reaction solution, 21 g of potassium carbonate was added and stirred while heating to 110 ° C. with a mantle heater. After stirring for 3 hours, the reaction solution was dropped into a beaker containing 1000 mL of methanol, and the produced precipitate was collected by suction filtration. The precipitate collected by filtration was washed with 300 mL of methanol three times to obtain 67 g of a polyhydroxy polyether resin (hereinafter referred to as “resin (A)”) having a chemical structure represented by the following chemical formula (A). In the formula (A), n represents a positive integer.

  The molecular weight of the resin (A) was measured using a high performance liquid chromatograph GP8020 manufactured by Tosoh Corporation (column: Gelpak GL-A150S and GL-A160S manufactured by Hitachi Chemical Co., Ltd., eluent: tetrahydrofuran, flow rate: 1.0 ml / Min). As a result, it was Mn = 21684, Mw = 44388, Mw / Mn = 2. 047 in terms of polystyrene.

Comparative Example 1
4,4 ′-(9-fluorenylidene) -diphenol 45 g (manufactured by Sigma-Aldrich Japan) and 3,3 ′, 5,5′-tetramethylbiphenol diglycidyl ether 50 g (manufactured by Japan Epoxy Resin Co., Ltd., product) Name: YX-4000H) was dissolved in 1000 mL of N-methylpyrrolidone in a 3000 mL three-necked flask equipped with a Dimroth condenser tube, a calcium chloride tube, and a Teflon stirring rod connected to a stirring motor to obtain a reaction solution. . To this, 21 g of potassium carbonate was added and stirred while heating to 110 ° C. with a mantle heater. After stirring for 3 hours, the reaction solution was dropped into a beaker containing 1000 mL of methanol, and the produced precipitate was collected by suction filtration. The precipitate collected by filtration was further washed with 300 mL of methanol three times to obtain 75 g of a polyhydroxy polyether resin (hereinafter referred to as “resin (B)”) having a chemical structure represented by the following chemical formula (B). . In the formula (B), n represents a positive integer.

  When the molecular weight of the resin (B) was measured in the same manner as in Example 1, it was Mn = 15769, Mw = 38045, and Mw / Mn = 2.413 in terms of polystyrene.

Glass transition temperature and elastic modulus of resin Resin (A) synthesized in Example 1, resin (B) synthesized in Comparative Example 1, and bisphenol A-type phenoxy resin YP50S (product name, manufactured by Tohto Kasei Co., Ltd.) 30 g each in toluene A solution dissolved in 45 g of an ethyl acetate mixed solvent (weight ratio 1: 1) was applied to a PET film using a roll coater, and the coating film was dried in an oven at 70 ° C. for 10 minutes to obtain a resin film having a thickness of 50 μm. Produced. Using a resin film cut into 4 mm × 25 mm as a test piece, the glass transition temperature was measured by the TMA method using TMA / SS6000 (product name) manufactured by Seiko Instruments Inc. The measurement conditions were a distance between chucks of 10 mm, a measurement temperature range of 20 to 300 ° C., a heating rate of 5 ° C./min, and a tensile load of 0.5 MPa per unit cross-sectional area of the film. The measurement results of the glass transition temperature are shown in Table 1 together with the tensile elastic modulus at 25 ° C.

Example 2 Production of Film Adhesive
25 g of resin (A) synthesized in Example 1, 20 g of polyfunctional epoxy resin EP1032H60 (Japan Epoxy Resin Co., Ltd., product name), 20 g of bisphenol A type liquid epoxy resin EP828 (Japan Epoxy Resin Co., Ltd., product name), 35 g of microcapsule type curing agent HX-3941HP (manufactured by Asahi Kasei Co., Ltd., product name) and 100 g of insulating silica filler SE2050 (manufactured by Admatechs Co., Ltd., product name, average particle size 0.4 to 0.6 μm) are toluene. -A varnish was prepared by dissolving in an ethyl acetate mixed solvent (weight ratio 1: 1). This varnish was applied onto a separator film (PET film) using a roll coater and dried in an oven at 70 ° C. for 10 minutes to obtain a film adhesive having a thickness of 50 μm.

Example 3
A varnish having the same composition as in Example 2 was prepared except that 3 g of an imidazole-based curing agent 2PHZ (manufactured by Shikoku Kasei Co., Ltd., product name) was further added. This varnish was applied onto a separator film (PET film) using a roll coater and dried by heating in an oven at 70 ° C. for 10 minutes to obtain a film adhesive having a thickness of 50 μm.

Comparative Example 2
A film adhesive having a thickness of 50 μm was obtained in the same manner as in Example 2 except that bisphenol A type phenoxy resin YP50S (product name, manufactured by Tohto Kasei Co., Ltd.) was used instead of the resin (A). When the molecular weight of YP50S was measured in the same manner as in Example 1, Mn = 21050, Mw = 50093, and Mw / Mn = 2.380 in terms of polystyrene.

Comparative Example 3
A film adhesive having a thickness of 50 μm was obtained in the same manner as in Example 3 except that the resin (B) synthesized in Comparative Example 1 was used instead of the resin (A).

Comparative Example 4
A film adhesive having a thickness of 50 μm was obtained in the same manner as in Example 3 except that bisphenol A type phenoxy resin YP50S (manufactured by Toto Kasei Co., Ltd., product name) was used instead of resin (A).

Evaluation of Film Adhesive The film adhesives prepared in Examples 2 and 3 and Comparative Examples 2 to 4 were evaluated according to the following procedure. The evaluation results are summarized in Table 2. In the following, a cured film obtained by curing a film adhesive by heating in an oven at 200 ° C. for 1 hour was used.

Average linear expansion coefficient The average linear expansion coefficient by the TMA method was measured using TMA / SS6000 (product name) manufactured by Seiko Instruments Inc. with a cured film cut into a size of 3 mm to 30 mm as a test piece. The measurement conditions were a distance between chucks of 15 mm, a measurement temperature range of 20 to 300 ° C., a heating rate of 5 ° C./min, and a tensile load of 0.5 MPa per unit cross-sectional area of the test piece.

Elastic modulus and glass transition temperature Using a cured film cut into a size of 5 mm × 45 mm as a test piece, an elastic modulus (40 ° C. and 250 ° C.) and glass by a DMA method using a DMS6100 (product name) manufactured by Seiko Instruments Inc. The transition temperature (the temperature at which tan δ is maximized) was measured. The measurement conditions were a chuck distance of 20 mm, a frequency of 1 Hz, a measurement temperature range of 20 to 300 ° C., and a temperature increase rate of 5.0 ° C./min.

Moisture absorption rate The cured film was cut into a size of 20 mm × 20 mm, dried for 24 hours in an oven at 125 ° C., measured for dry weight, and then 168 in a treatment tank adjusted to 85 ° C./85% relative humidity. The weight after standing for a period of time was measured, and the moisture absorption rate was measured based on the increment from the dry weight.

Adhesive force Using the adhesive force measuring apparatus schematically shown in FIG. 2, the adhesive force of the film adhesive to the polyimide film was measured by the following procedure.

  An adhesive force measuring member 51 obtained by cutting a 625 μm thick silicon wafer having a polyimide film formed on the surface into a size of 12 mm × 12 mm was prepared. Separately, a part of a 625 μm thick silicon wafer having a polyimide film formed on the surface is cut into half the thickness from the polyimide forming surface, leaving a hook portion 52 a of about 180 μm in thickness of 5 mm × 5 mm. A member 52 for measuring adhesive strength obtained by cutting out into a size was prepared.

  The film adhesive is cut into a size of 5 mm × 5 mm, placed on the polyimide forming surface of the adhesion measuring member 51, and temporarily heated and pressed from the separator side for 3 seconds at 90 ° C. and 0.5 MPa. Crimped. After the separator film is peeled off, the adhesive is measured so that the polyimide-forming surface of the adhesive force measuring member 52 and the film adhesive temporarily bonded to the adhesive force measuring member 1 are in contact with each other. Heating and pressurizing for 2 seconds and then press-bonding to obtain a connection body in which the adhesion measuring members 51 and 52 are connected via the adhesive layer 40 formed of a film adhesive. This connected body was heated in an oven at 150 ° C. for 2 hours and left in a treatment tank adjusted to 85 ° C./85% relative humidity for 24 hours. Then, the connection body is placed on the hot plate 3 heated to 260 ° C., and the hook 6 connected to the load cell 5 is hooked on the hook 52 a and pulled in the direction of arrow A to pull the adhesive force measuring member 52. The maximum stress at this time was defined as the adhesive strength.

Connection reliability A film-like adhesive was applied to a glass epoxy board having a copper wiring pattern that had been subjected to Ni / flash Au plating, and pre-crimped by heating and pressurizing from the separator side for 3 seconds at 90 ° C. and 0.5 MPa. . The separator film is peeled off, and the TEG chip (size: 10 mm x 10 mm, number of bumps: 184, bump arrangement: peripheral, bump pitch: 200 µm) and the copper wiring pattern on the glass epoxy board are aligned. Then, the film was heat-bonded and pressed for 20 seconds under the conditions of 180 ° C. and 1.0 N / bump, followed by final pressure bonding. Subsequently, the film adhesive was cured by heating in an oven at 150 ° C. for 2 hours to obtain a connection body in which the glass epoxy substrate and the TEG chip were connected via the film adhesive.

  The obtained connection body was dried in an oven at 125 ° C. for 24 hours, left in a treatment tank adjusted to 85 ° C./relative humidity 85% for 168 hours, and then subjected to IR reflow treatment (maximum 265 ° C.) three times. . The daisy chain connection resistance of the connection body before and after the reflow treatment was measured. Moreover, the presence or absence of peeling after reflow was confirmed by observation using an ultrasonic flaw detector. When the resistance increase was 10% or less of the initial resistance and no separation was observed, the connection reliability was deemed acceptable.

  When Example 2 and Comparative Example 2 are compared, the glass transition temperature of Example 2 is about 30 higher than that of Comparative Example 2 although the glass transition temperature of resin (A) and bisphenol A type phenoxy resin YP50S are substantially the same. ℃ higher. Further, in Example 2, the water absorption was about 0.15% lower than that in Comparative Example 2, and the adhesive strength after moisture absorption was improved, and no defect was seen even in the reflow treatment.

  Further, when Example 2 and Comparative Example 3 are compared, the glass transition temperature of Resin (A) is about 60 ° C. lower than the glass transition temperature of Resin (B), but the glass transition temperature of Example 2 and Comparative Example are compared. The glass transition temperature of 3 showed almost the same value. In addition, Example 2 showed higher adhesive strength.

  When Example 3 and Comparative Example 4 are compared, the glass transition temperature of both Example 3 and Comparative Example 4 is higher than that of Example 2 and Comparative Example 2, but Example 3 is about 20 ° C. higher than Comparative Example 4. The value is shown. Moreover, although the moisture absorption rate was lower in Comparative Example 4, no defect was found in the reflow process in Example 3, whereas a defect occurred in the reflow process in Comparative Example 4.

  As described above, by using the polyhydroxy polyether resin according to the present invention, it has high heat resistance and maintains high adhesive force even after being exposed to a high temperature and high humidity environment when used as an adhesive. It was confirmed that a resin composition that can be obtained is obtained. It was also confirmed that connection reliability was improved by connecting circuit members using the resin composition of the present invention.

It is sectional drawing which shows one Embodiment of the circuit board which concerns on this invention. It is a schematic diagram which shows an adhesive force measuring apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Circuit board, 10 ... Connection part, 11 ... Matrix, 12 ... Conductive particle, 20, 30 ... Circuit member, 21, 31 ... Circuit board, 22, 32 ... Circuit electrode.

Claims (13)

The following general formula (I):

[In the formula (I), R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are each independently a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, A hydroxyalkyl group having 1 to 6 carbon atoms or a halogen atom is shown. ]
A polyhydroxy polyether resin comprising a chemical structure represented by: The following general formula (II):

[In the formula (II), R ^a , R ^b , R ^c and R ^d each independently have a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a cyclic alkyl group having 6 carbon atoms, or a substituent. An aryl group which may be substituted, an aralkyl group which may have a substituent, or a halogen atom. ]
The polyhydroxy polyether resin of Claim 1 containing the chemical structure represented by these. The following general formula (III):

[In the formula (III),
^{R 1, R 2, R 3} , R 4, R 5, R 6, R 7 and ^{R 8} independently represent a hydrogen atom, linear or branched alkyl group having 1 to 6 carbon atoms, hydroxy having from 1 to 6 carbon atoms Represents an alkyl group or a halogen atom,
R ^a , R ^b , R ^c and R ^d are each independently a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, a cyclic alkyl group having 6 carbon atoms, and an aryl group which may have a substituent. , Represents an aralkyl group or a halogen atom which may have a substituent,
n represents a positive integer. ]
A polyhydroxy polyether resin comprising a chemical structure represented by:   The polyhydroxy polyether resin according to any one of claims 1 to 3, wherein a polystyrene-reduced weight average molecular weight is 5,000 to 1,000,000.   The resin composition containing the polyhydroxy polyether resin as described in any one of Claims 1-4, and a three-dimensional crosslinkable resin component.   The resin composition of Claim 5 whose mass ratio of the said polyhydroxy polyether resin and the said three-dimensional crosslinkable resin component is 1 / 99-99 / 1.   The resin composition according to claim 5 or 6, wherein the three-dimensional crosslinkable resin component is crosslinked by heating.   The resin composition according to any one of claims 5 to 7, wherein the three-dimensional crosslinkable resin component contains a microcapsule-type latent curing agent.   The resin composition as described in any one of Claims 5-8 which is a film form.   The resin composition as described in any one of Claims 5-9 containing an insulating inorganic filler or a whisker.   The resin composition according to any one of claims 5 to 10, comprising conductive particles.   A circuit board and a circuit electrode formed on the main surface of the circuit board, and a pair of circuit members arranged so that the circuit electrodes are arranged to face each other, the circuit electrodes arranged to face each other The adhesive for circuit member connection which consists of a resin composition as described in any one of Claims 5-11 used in order to adhere | attach so that it may electrically connect. A pair of circuit members having a circuit board and circuit electrodes formed on the main surface of the circuit board, the circuit electrodes being arranged to face each other;
A connection part that is interposed between the pair of circuit members and bonds the pair of circuit members so that the circuit electrodes arranged opposite to each other are electrically connected;
With
The circuit board in which the said connection part is formed with the adhesive agent for a circuit member connection of Claim 12.

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