JP2006022195A - Curable resin composition, adhesive epoxy resin sheet an circuit board joint product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a curable resin composition which has good storage stability at room temperature, is quickly curable, and develops good adhesion reliability after cured, to provide an adhesive epoxy resin sheet using the curable resin composition, and to provide a circuit board joint product obtained by using them. <P>SOLUTION: This curable resin composition comprising an epoxy resin (preferably having a polycyclic hydrocarbon skeleton as a main chain), a solid polymer having functional groups capable of reacting with epoxy groups (preferably an acrylic polymer having an epoxy equivalent of 100 to 1000), and a curing agent for the epoxy resin is characterized in that the curing agent for the epoxy resin is a solid alicyclic acid anhydride having a melting point of ≤110°C (especially preferably 1-isopropyl-4-methylbicyclo-[2.2.2]-oct-5-ene-2,3-dicarboxylic anhydride). The adhesive epoxy resin sheet, and the circuit board joint product. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a curable resin composition suitably used as an adhesive for electronic materials, an adhesive epoxy resin sheet, and a circuit board assembly.

Various adhesives for electronic materials have been developed in response to recent demands for miniaturization and higher performance of semiconductor devices.
These adhesives for electronic materials are required to have a high degree of reliability with respect to each characteristic, and therefore, epoxy resins that have low curing shrinkage, high adhesive strength, and a wide variety of types that are easy to formulate are the most. It is often used. Generally, general-purpose liquid epoxy resins such as bisphenol A type liquid epoxy resin and bisphenol F type liquid epoxy resin are widely used because of their excellent workability.
However, the higher demands for various current reliability cannot be fully met with adhesives for electronic materials using these general-purpose liquid epoxy resins. New epoxy resins or new epoxy resin compositions Development of goods is requested.

Specific required performance required as an adhesive for electronic materials includes, for example, adhesion reliability (heat resistance, moisture resistance, cold cycle resistance, solder reflow resistance), storage stability, and quick curing. .
Among these, from the viewpoint of moisture resistance and solder reflow resistance, it is always necessary that the cured adhesive has a low water absorption and a low water absorption. This is because if the water absorption of the cured adhesive is high, water can easily enter the bonding interface, which may reduce the adhesive strength of the interface. Moreover, it is because there exists a possibility that a water | moisture content may vaporize rapidly with the solder reflow temperature which reaches 200-260 degreeC, and an electronic component may be destroyed.

In addition, in order to improve the thermal cycle resistance, a large amount of inorganic filler is filled to reduce the linear expansion coefficient (linear expansion coefficient), but if a large amount of inorganic filler is filled, the adhesive Since the elastic modulus is high, there is a problem that the cured adhesive is difficult to relieve stress.
Therefore, in order to reduce the generated stress, a film-like adhesive for circuit connection containing an epoxy resin and acrylic rubber has been proposed (see, for example, Patent Document 1).
However, film adhesives with added rubber polymers achieve stress relaxation at the expense of lowering heat resistance, so that the thermal cycle resistance is improved, but high heat resistance / humidity resistance and high resistance. It has been practically difficult to achieve both cold cycle performance.

  Also, in general, as a curing agent in an epoxy resin-based curable composition, there are many types and amounts of amines, but when compared with such amines, the cured product has excellent electrical and mechanical properties. Therefore, acid anhydrides are often used (see Non-Patent Document 1, for example). However, sufficient studies have not been made as a curing agent for adhesives for electronic materials.

  On the other hand, considering the storage stability of the adhesive for electronic materials, a composition that prioritizes properties such as quick curing is generally required, so that refrigeration or frozen storage is generally required. However, when looking at the production process steps of electronic materials such as semiconductor devices, the actual situation is that production is performed in a room temperature environment of 20-30 ° C.

On the other hand, the die attach film is used when processing a semiconductor element (semiconductor chip, IC chip), for example, when bonding a silicon chip to a metal frame, a multilayer board, an organic substrate (build-up substrate, etc.), a ceramic substrate, etc. It is a film insulating material used for a resin, and a resin composition comprising an epoxy resin (B-1) and an epoxy resin curing agent (B-2) is used as a thermosetting adhesive component (B). (For example, refer to Patent Document 2).
The die attach film is also required to have the same performance as the above required performance as an adhesive for electronic materials, and as a method of obtaining a silicon chip with a die attach film, a method of directly attaching a film at the wafer stage, Although there is a method of individually attaching to silicon chips singulated at the wafer level, there is no difference in required performance.

Japanese Patent No. 3342703: Claim 2 etc. JP 2002-294177 A: Claim 1 and paragraph 0030 and the like "Epoxy resin handbook", Nikkan Kogyo Shimbun, December 25, 1987, pages 135 and 180

In the course of advancing research on an epoxy curable resin composition as an adhesive for electronic materials, the present inventors may obtain a composition having excellent adhesion reliability when an acid anhydride is used as a curing agent. On the other hand, for example, when using a solid acid anhydride with a high melting point, it may be difficult to dissolve or it may remain in the cured product as an insoluble component, which may cause problems in adhesion reliability. did.
In addition, when a liquid curing agent is used at room temperature, the curing reaction proceeds at a low speed in the unreacted curable resin composition, and the storage stability is low. I got the knowledge that there is a limitation of pot life.

  In particular, in the case of a die attach film, curing of the resin begins to proceed gradually while a series of work steps such as dicing and bonding starting from sticking to a silicon wafer is performed in the room temperature environment of 20-30 ° C., Since the resin fluidity at the time of adhesion is lowered, the adhesion may be deteriorated. In other words, the problem that the adhesive reliability of the cured product may be impaired due to insufficient storage stability is recognized. In addition, the above work is performed in a room temperature environment of 20-30 ° C., so that the die attach film loses its flexibility and becomes brittle, and as a result cannot be cut into a predetermined size (the processing accuracy is poor). Recognized.

  The present invention has been completed under the above-mentioned problems of the prior art relating to epoxy-based curable resin compositions, and the knowledge of the inventors, etc., and its purpose is to have storage stability at room temperature, A curable resin composition that is instantly curable and exhibits adhesive reliability after curing, an adhesive epoxy resin sheet using the curable resin composition, and an electronic component assembly obtained using the same It is to provide.

  The curable resin composition of the invention described in the claims (hereinafter referred to as “present invention 1”) includes an epoxy resin, a solid polymer having a functional group that reacts with the epoxy group, and a curing agent for the epoxy resin. The epoxy resin curing agent is a solid alicyclic acid anhydride having a melting point of 110 ° C. or lower.

  The curable resin composition of the invention described in claim 2 (hereinafter referred to as “present invention 2”) is an epoxy resin in which the epoxy resin has a polycyclic hydrocarbon skeleton in the main chain, and has a function of reacting with an epoxy group. The solid polymer having a group is a polymer having an epoxy group and has an epoxy equivalent of 100 to 1,000.

（Ｒ¹ 及びＲ² はアルキル基を表す） The curable resin composition of the invention described in claim 3 (hereinafter referred to as “present invention 3”) is a solid alicyclic acid anhydride having a melting point of 110 ° C. or less in the curable resin composition described in claim 1 or 2. The product is represented by the following general formula (1).

(R ¹ and R ² represent an alkyl group)

  The adhesive epoxy resin sheet of the invention according to claim 4 (hereinafter referred to as “present invention 4”) is obtained by molding the curable resin composition according to any one of claims 1 to 3 into a sheet shape. It is characterized by

  The circuit board assembly of the invention described in claim 5 (hereinafter referred to as “present invention 5”) is made of a metal lead frame, a ceramic substrate using the curable resin composition described in any one of claims 1 to 3. The semiconductor element is formed by bonding at least one circuit substrate out of a resin substrate, a silicon substrate, a compound semiconductor substrate, and a glass substrate.

  The circuit board assembly of the invention described in claim 6 (hereinafter referred to as “present invention 6”) is made of a metal lead frame, a ceramic substrate, a resin substrate, a silicon substrate, an adhesive epoxy resin sheet according to claim 4, It is characterized in that at least one circuit board out of a compound semiconductor substrate and a glass substrate is bonded to a semiconductor element.

  The circuit board assembly of the invention according to claim 7 (hereinafter referred to as “present invention 7”) is the circuit board assembly according to claim 5 or 6, wherein the resin substrate is a glass epoxy substrate, bismaleimide triazine. It is a substrate or a polyimide substrate.

Next, the contents of each invention will be described in detail.
The adhesive referred to in the present invention includes an adhesive.

The curable resin composition of the present invention 1 contains an epoxy resin, a solid polymer having a functional group that reacts with an epoxy group, and a curing agent that is a solid alicyclic acid anhydride having a melting point of 110 ° C. or lower. . In this case, the “epoxy resin” refers to an uncured resin having an average of 1 or more, preferably 2 or more epoxy groups in the molecule.
The epoxy resin is not particularly limited, and bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, polyethylene glycol type epoxy resin, and polycyclic hydrocarbon skeleton are used as the main chain. The epoxy resin which has is mentioned.
Among these, an epoxy resin having a polycyclic hydrocarbon skeleton in the main chain is preferable. When an epoxy resin having a polycyclic hydrocarbon skeleton in the main chain is contained, the cured product is rigid and impedes molecular movement, exhibits excellent mechanical strength and heat resistance, and also absorbs water. It is because it becomes low and expresses excellent moisture resistance.

The solid polymer having a functional group that reacts with the epoxy group is not particularly limited. First, examples of the functional group that reacts with the epoxy group include an amino group, a urethane group, an imide group, a hydroxyl group, and a carboxyl group, as well as an epoxy group. Examples of the solid polymer having these include a copolymer polymer having an acrylic acid or methacrylic acid ester monomer or an acrylic acid or methacrylic acid derivative as a comonomer.
Among these, a polymer having an epoxy group is preferable. In a curable resin composition containing an epoxy resin, a solid polymer having a functional group that reacts with an epoxy group, and a curing agent for epoxy resin, a cured product obtained by containing a polymer having an epoxy group as the solid polymer. This is because generally exhibits excellent flexibility. The weight average molecular weight of the solid polymer is preferably 10,000 or more, more preferably 100,000 or more. Conversely, when the weight average molecular weight is less than 10,000, the film forming property of the curable resin composition becomes insufficient, and the flexibility of the cured product of the curable resin composition may not be sufficiently improved.

  Since the curable resin composition of the present invention 1 contains the above specific curing agent for epoxy resin, it has good storage stability at room temperature, and also contains a solid polymer having a functional group such as an epoxy resin and an epoxy group. In combination, the epoxy resin and the solid polymer are hardened and quickly cured, preferably under heating, and exhibit excellent solder reflow resistance, dimensional stability, etc., and exhibit high adhesive reliability. .

In the present invention 1, a solid alicyclic acid anhydride having a melting point of 110 ° C. or lower, that is, an alicyclic acid anhydride having a melting point of 110 ° C. or lower as an essential component is contained as a curing agent. The property may be powder. The melting point is preferably 100 ° C. or lower, and more preferably 80 ° C. or lower. In view of the initial storage stability of the curable resin composition, and further from the viewpoint of moisture resistance and solder reflow resistance of the resin after curing, it is preferable to have hydrophobicity, and thus an alicyclic acid anhydride curing agent is used. .
The melting point of the curing agent in the present invention 1 has a structure in which, for example, a sample is placed between a capillary tube or a glass plate, the whole is immersed in a bath, gradually heated from the outside, and the temperature at the moment of changing to a liquid phase is measured. It is measured using a general “melting point measuring device”.

A solid acid anhydride having a melting point exceeding 110 ° C. has an adverse effect on the adhesive reliability of the curable resin composition due to, for example, being easily retained in the cured product as an insoluble component, or has a high curing reaction temperature. Therefore, there is an inconvenience that the application range and members of the composition are limited.
In addition, when the curable resin composition is formed into a sheet shape by the method described later, the glass transition temperature (Tg) before curing of the sheet itself is considerably increased, for example, causing cracks in the sheet or the like, and processing. -It tends to be a sheet with poor handling properties.
On the other hand, in the case of a liquid acid anhydride, if it is left at room temperature, it changes from an acid anhydride to a free acid due to the influence of moisture or the like and changes to a solid state, so that the state of the curable resin composition is likely to deteriorate. The curing reaction proceeds at a low speed in the unreacted curable resin composition, and the storage stability is low.

  Specific examples of the solid alicyclic acid anhydride having a melting point of 110 ° C. or less include hexahydrophthalic anhydride (34 ° C.), glycerin bis (anhydrotrimellitate) monoacetate (70 ° C.), tetrahydrophthalic anhydride (100 ° C. ), Trialkyltetrahydrophthalic anhydride-maleic anhydride adduct, and acid anhydrides represented by the above general formula (1). The parentheses indicate melting points.

（Ｒ³ 、Ｒ⁴ は、互いに独立して、メチル基、エチル基、プロピル基、イソプロピル基を表す）
構造的には、Ｒ³ は一般式（１）におけるＲ¹ が４位の炭素と結合した場合に相当しＲ⁴ は一般式（１）におけるＲ² が１位の炭素と結合した場合に相当する。 The case where the acid anhydride represented by the general formula (1) is used as the curing agent is the curable resin composition of the present invention 3, wherein R ¹ and R ² represent an alkyl group, preferably a lower alkyl group.
A more preferable curing agent in the curable resin composition of the present invention 3 is an acid anhydride represented by the general formula (2).

(R ³ and R ⁴ each independently represent a methyl group, an ethyl group, a propyl group, or an isopropyl group)
Structurally, R ³ corresponds to the case where R ¹ in the general formula (1) is bonded to the 4-position carbon, and R ⁴ corresponds to the case where R ² in the general formula (1) is bonded to the 1-position carbon. To do.

Among the acid anhydrides represented by the general formula (2), 1-isopropyl-4-methylbicyclo- [2.2.2] -oct-5-ene-2,3-dicarboxylic acid anhydride (about 65 ° C.) is Are particularly preferably used.
This acid anhydride is a solid powder, is alicyclic and has an alkyl side chain having 3 carbon atoms, so it is highly hydrophobic, and it has high heat resistance to improve the glass transition temperature of the cured resin composition. Excellent and also excellent in moisture resistance and solder reflow resistance to improve hydrophobicity. Furthermore, since the melting point is about 65 ° C., the glass transition temperature of the curable resin composition can be designed to be room temperature or lower, so it can be formed into various shapes including a sheet shape, and the heat curing condition is about 120 ° C. or higher. Since it can be applied, it can be used for joining a wide range of members.

In the curable resin composition of the present invention 3, the blending amount of the solid alicyclic acid anhydride having a melting point of 110 ° C. or lower is usually 100 equivalent to the total epoxy equivalent of the epoxy resin and the other polymer having an epoxy group. 70 to 90 equivalents, that is, an amount corresponding to 70 to 90% of the theoretically required equivalent.
In the curable resin composition of the present invention 1, in order to adjust the curing rate and the physical properties of the cured product, a curing accelerator may be used in combination with the curing agent for epoxy resin, ensuring a practical curing rate. Therefore, it is preferable to use a curing accelerator in combination.

  The curing accelerator is not particularly limited and includes, for example, an imidazole-based curing accelerator, a tertiary amine-based curing accelerator, and the like, among others, a reaction for adjusting the curing speed and the physical properties of the cured product. Since it is easy to control the system, an imidazole curing accelerator is preferably used. These curing accelerators may be used alone or in combination of two or more.

  The imidazole curing accelerator is not particularly limited. For example, 1-cyanoethyl-2-phenylimidazole in which the 1-position of imidazole is protected with a cyanoethyl group, or a trade name “2MA-0K whose basicity is protected with isocyanuric acid”. (Shikoku Kasei Kogyo Co., Ltd.). These imidazole type hardening accelerators may be used independently and 2 or more types may be used together.

When an acid anhydride curing agent is used in combination with a curing accelerator such as an imidazole curing accelerator, the addition amount of the acid anhydride curing agent is preferably 60 equivalent to the theoretically required equivalent to the epoxy group. -100%, more preferably 70-90%.
If the addition amount of the acid anhydride curing agent is excessive more than necessary, chlorine ions may be easily eluted by moisture from the cured product of the curable resin composition of the present invention. For example, when the elution component is extracted with hot water from the cured product of the curable resin composition of the present invention, the pH of the extracted water is lowered to about 4 to 5, and a large amount of chloride ions extracted from the epoxy resin is eluted. May end up.

  The curable resin composition of the present invention 1 includes rubber particles having a core-shell structure in which the glass transition temperature of the core (core material) is 20 ° C. or lower and the glass transition temperature of the shell (outer shell) is 40 ° C. or higher. It is preferable that By containing such rubber particles, the cured product of the curable resin composition of the present invention can form a stable phase separation structure of the rubber component with respect to the epoxy resin that is the matrix resin, and is flexible. This is because excellent stress relaxation properties are exhibited.

  The rubber particles have a core-shell structure including a core having a glass transition temperature of 20 ° C. or lower and a shell having a glass transition temperature of 40 ° C. or higher. The rubber particles may be core-shell structured particles composed of two or more layers, and in the case of core-shell structured particles composed of three or more layers, the shell means the outermost shell.

  When the glass transition temperature of the core of the rubber particles exceeds 20 ° C., the stress relaxation property of the cured product of the curable resin composition of the present invention 2 is not sufficiently improved. Further, when the glass transition temperature of the shell of the rubber particles is less than 40 ° C., the rubber particles are fused (aggregated) or poor dispersion occurs in the epoxy resin composition. The shell of the rubber particles is preferably incompatible with the epoxy resin, or gelled by some crosslinking and not dissolved in the epoxy resin.

  As the resin component constituting such rubber particles, any resin component may be used as long as the glass transition temperature of the core can be 20 ° C. or less and the glass transition temperature of the shell can be 40 ° C. or more. In general, an allyl resin is preferably used because of the wide design range. These resin components may be used alone or in combination of two or more.

  Moreover, the shell of the rubber particles may have a functional group that reacts with an epoxy group in the epoxy resin. The functional group that reacts with the epoxy group is not particularly limited, and examples thereof include an amino group, a urethane group, an imide group, a hydroxyl group, a carboxyl group, and an epoxy group. The hydroxyl group and the epoxy group are preferably used in that the wettability and storage stability of the curable resin composition in the present invention are not lowered. These functional groups that react with the epoxy group may be used alone or in combination of two or more.

Although the said rubber particle is not specifically limited, It is preferable that an average particle diameter is 3 micrometers or less. When the average particle diameter of the rubber particles exceeds 3 μm, the stress relaxation property of the cured product of the curable resin composition in the present invention may not be sufficiently improved. Moreover, when using the curable resin composition in this invention as an adhesive epoxy resin paste, for example, fluidity | liquidity becomes inadequate and coating property and the filling property to a gap | interval part may be inhibited.
Moreover, when using the curable resin composition of this invention 1 as an adhesive epoxy resin sheet of this invention 4, for example, sheet | seat shaping | molding of a thin film may become difficult.

Commercially available products of such rubber particles are not particularly limited. For example, “Paracron” such as “Paracron RP-101”, “Paracron RP-103”, and “Paracron RP-412” manufactured by Negami Kogyo Co., Ltd. Series, trade names “Staffyroid IM-101”, “Stuffyroid IM-203”, “Stuffyroid IM-301”, “Stuffyroid IM-401”, “Stuffyroid IM-601”, “Grants Kasei” “Staffroid” series, such as “Staffyroid AC-3355”, “Stuffyroid AC-3364”, “Stuffyroid AC-3816”, “Stuffyroid AC-3732”, “Stuffyroid AC-4030”, manufactured by Zeon Kasei Co., Ltd. “Zeon” series such as “Zeon F351”, and “Metal” manufactured by Mitsubishi Rayon Co., Ltd. "Lene C-140A", "Metabrene C-201A", "Metabrene C-215A", "Metabrene C-223A", "Metabrene C-303A", "Metabrene C-323A", "Metabrene C-102", "Metabrene" C-132 "," methabrene C-202 "," methabrene E-901 "," methabrene W-341 "," methabrene W-300A "," methabrene W-450A "," methabrene S-2001 "," methabrene SX " “-005”, “methabrene SX-006”, “methabrene SRK200” and other “methabrene” series.
Examples of commercially available epoxy resins in which rubber particles are dispersed in advance include “Eposet” series such as “Eposet BPA-828” and “Eposet BPF-807” manufactured by Nippon Shokubai Co., Ltd. These rubber particles and epoxy resin in which rubber particles are dispersed in advance may be used alone or in combination of two or more.

Moreover, in the curable resin composition of this invention 1, you may add an inorganic filler suitably.
In general, in order to increase the reliability of an adhesive for electronic materials and the like, conventionally, it has been essential to add a large amount of an inorganic filler. It is well known that the addition of this inorganic filler improves water absorption and elastic modulus and improves moisture resistance, etc., but the inorganic filler particles are intercalated between the electrodes during pressure welding between the electrodes. In particular, when bonding between narrow gap electrodes, adhesion failure may occur due to the presence of the inorganic filler.
The inorganic filler is often used as spherical silica. The spherical silica basically has a particle size distribution and may have very coarse particles as a probability. In particular, when a large amount of inorganic filler (spherical silica) is added, the probability that very coarse particles are included becomes very high, and the above-mentioned disadvantages are likely to occur.
On the other hand, if the inorganic filler has a very uniform particle size distribution and the inorganic filler has a very small maximum particle size, the above-mentioned disadvantages hardly occur. It may be added to the curable resin composition.
Specifically, the maximum particle size of the inorganic filler is 3 μm or less, and the addition amount when the total resin is 100 parts by weight is 60 parts by weight or less, more preferably 30 parts or less. In addition, the whole resin in this case means the total amount of an epoxy resin and a polymer having an epoxy group.

  When containing an inorganic filler having a maximum particle size exceeding 3 μm, the above-mentioned inconvenience is likely to occur, and when the curable resin composition of the present invention is used for a substrate requiring a via hole, The roundness of the through hole is lowered, and the smoothness of the processed surface of the via hole may be lost due to the inorganic filler.

The inorganic filler having a maximum particle size of 3 μm or less and not including coarse particles is not particularly limited, and examples thereof include silica such as fumed silica and colloidal silica, glass fibers, and alumina fine particles. Among them, silica is preferable. In particular, hydrophobic silica whose surface has been subjected to a hydrophobic treatment is more preferably used.
These inorganic fillers may be used alone or in combination of two or more. In addition, in the curable resin composition of this invention 1, if the maximum particle diameter is 3 micrometers or less, the organic filler which consists of a low molecular-weight fine particle organic substance may contain.

  When the curable resin composition of the present invention 1 contains an inorganic filler having a maximum particle size of 3 μm or less, the epoxy resin preferably has a polycyclic hydrocarbon skeleton in the main chain, and the high epoxy resin having the epoxy group. When exceeding 30 parts by weight with respect to 100 parts by weight as the total amount with the molecular polymer, the roundness of the through hole at the time of laser processing when the curable resin composition of the present invention is used for a substrate requiring a via hole. And the inorganic filler may lose the smoothness of the processed surface of the via hole, or the viscosity of the curable resin composition may become too high, thereby impairing the coatability.

  The curable resin composition of the first aspect of the present invention may include other resins (thermoplastic resins) different from any of the above “epoxy resin” and “solid polymer having a functional group that reacts with an epoxy group” as necessary. Or a thermosetting resin) may be contained.

  The thermoplastic resin is not particularly limited, and examples thereof include polyvinyl acetal resins such as vinyl acetate resins, ethylene-vinyl acetate copolymers, acrylic resins, and polyvinyl butyral resins, styrene resins, and saturated polyester resins. , Thermoplastic urethane resins, polyamide resins, thermoplastic polyimide resins, ketone resins, norbornene resins, styrene-butadiene block copolymers, and the like. These thermoplastic resins may be used alone or in combination of two or more.

  The thermosetting resin is not particularly limited. For example, amino resins such as urea resins and melamine resins, phenol resins, unsaturated polyester resins, thermosetting urethane resins, thermosetting polyimide resins, An amino alkyd resin etc. are mentioned. These thermosetting resins may be used alone or in combination of two or more. Moreover, the said thermoplastic resin and thermosetting resin may be used independently, respectively, and both may be used together.

  When the curable resin composition of the present invention 1 is used as, for example, a paste-like adhesive epoxy resin paste, the thermoplastic resin or thermosetting resin functions as a thickener. At this time, the weight average molecular weight of the thermoplastic resin or thermosetting resin is not particularly limited as long as the viscosity of the paste does not become extremely high. Further, if necessary, a solvent may be added to adjust the viscosity of the paste.

  The thermoplastic resin and thermosetting resin preferably have a functional group that reacts with an epoxy group. As the thermoplastic resin or thermosetting resin has a functional group that reacts with an epoxy group, the cured product of the curable resin composition of the present invention exhibits better mechanical strength and heat resistance. It becomes.

  Although it does not specifically limit as a functional group which reacts with the said epoxy group, For example, an amino group, a urethane group, an imide group, a hydroxyl group, a carboxyl group, an epoxy group etc. are mentioned. These functional groups that react with the epoxy group may be used alone or in combination of two or more.

  When the curable resin composition of the present invention is used as an adhesive epoxy resin paste whose viscosity is adjusted with a solvent, it reacts with an epoxy group at a temperature of about 150 to 230 ° C. among functional groups that react with the epoxy group. It is preferable to use a hydroxyl group or an epoxy group. Although it does not specifically limit as resin which has a hydroxyl group or an epoxy group, For example, a polyvinyl butyral resin, an epoxy-group-containing acrylic resin, etc. are mentioned.

  When an amino group, a carboxyl group, or the like is used as a functional group that reacts with an epoxy group, the curable resin composition of the present invention is used as an adhesive epoxy resin paste whose viscosity is adjusted with a solvent, and is about 110 ° C. for drying the solvent. Since the paste reacts with the epoxy group at a temperature of 5 ° C., the paste becomes a semi-cured state (B stage state), and the coating property (dispensing property) of the paste is hindered, the adhesion of the paste to the adherend, Moisture-resistant adhesiveness may decrease.

  Moreover, the equivalent of the functional group that reacts with the epoxy group of one thermoplastic resin or thermosetting resin is not particularly limited, but is preferably 10,000 or less, more preferably 1000 or less. . By using a thermoplastic resin or a thermosetting resin having a functional group that reacts with an equivalent amount of an epoxy group, the cured product of the curable resin composition of the present invention can form a network having a high crosslinking density. it can. In addition, the equivalent of the functional group that reacts with the epoxy group is the total number of functional groups that react with the epoxy group present in one thermoplastic resin or thermosetting resin, based on the weight average molecular weight of the thermoplastic resin or thermosetting resin. The value divided by.

The curable resin composition of the present invention 2 is the curable resin composition of the present invention 1, wherein the epoxy resin is an epoxy resin having a polycyclic hydrocarbon skeleton in the main chain, and has a functional group that reacts with the epoxy group. The solid polymer is a polymer having an epoxy group and has an epoxy equivalent of 100 to 1,000.
The epoxy resin having the above-mentioned polycyclic hydrocarbon skeleton in the main chain is a cured product using the same, which inhibits the movement of molecules, exhibits excellent mechanical strength and heat resistance, and absorbs water. Therefore, excellent moisture resistance and solder reflow resistance are exhibited.

The epoxy resin having a polycyclic hydrocarbon skeleton in the main chain is not particularly limited, and examples thereof include an epoxy resin having a dicyclopentadiene skeleton such as dicyclopentadiene dioxide and a phenol novolac epoxy resin having a dicyclopentadiene skeleton. (Hereinafter referred to as “dicyclopentadiene type epoxy resin”), 1-glycidylnaphthalene, 2-glycidylnaphthalene, 1,2-diglycidylnaphthalene, 1,5-diglycidylnaphthalene, 1,6-diglycidylnaphthalene, 1 Epoxy resins having a naphthalene skeleton such as 1,7-diglycidylnaphthalene, 2,7-diglycidylnaphthalene, triglycidylnaphthalene, 1,2,5,6-tetraglycidylnaphthalene (hereinafter referred to as “naphthalene type epoxy resin”) , Tetrahydroxyfe Examples include ethane type epoxy resin, tetrakis (glycidyloxyphenyl) ethane, 3,4-epoxy-6-methylcyclohexylmethyl-3,4-epoxy-6-methylcyclohexane carbonate, and among them, dicyclopentadiene type epoxy. Resins and naphthalene type epoxy resins are preferably used.
These epoxy resins having a polycyclic hydrocarbon skeleton in the main chain may be used alone or in combination of two or more. Moreover, the said dicyclopentadiene type | mold epoxy resin and naphthalene type | mold epoxy resin may each be used independently, and both may be used together.

  The above-mentioned dicyclopentadiene type epoxy resin is an epoxy resin comprising a dicyclopentadiene skeleton having an epoxy group, and this dicyclopentadiene type epoxy resin is rich in hydrophobicity. When used in a resin composition, the curable resin composition of the present invention 1 or 2 is hydrophobized, and the cured product has a low water absorption, even in a high temperature and high humidity environment typified by a pressure cooker test. High hydrophobicity is expressed.

  The dicyclopentadiene type epoxy resin preferably has a low degree of polymerization and / or a softening point. By using such a dicyclopentadiene type epoxy resin, when using the curable resin composition of this invention 1 or 2 as an adhesive epoxy resin paste, the fluidity | liquidity of a paste can be improved. Moreover, when using the curable resin composition of this invention 1 and 2 as an adhesive epoxy resin sheet, an appropriate softness | flexibility can be provided to the sheet | seat before hardening, and it can make it hard to break.

  The dicyclopentadiene type epoxy resin is not particularly limited, and examples thereof include dicyclopentadiene dioxide and phenol novolac epoxy resins having a dicyclopentadiene skeleton. These dicyclopentadiene type epoxy resins may be used alone or in combination of two or more.

The naphthalene type epoxy resin is an epoxy resin having a naphthalene skeleton having an epoxy group. In the second aspect of the invention, a naphthalene type epoxy resin that is liquid at room temperature is preferably used. Since the naphthalene type epoxy resin has a rigid naphthalene skeleton, when the curable resin composition of the present invention 2 is used as, for example, an adhesive epoxy resin sheet, the cured sheet maintains a high shape even under high temperature and high humidity. Properties can be obtained, and high moisture-resistant adhesiveness can be expressed.

When the curable resin composition of the present invention 1 or 2 is used as, for example, an adhesive epoxy resin paste, the naphthalene type epoxy resin preferably has a lower viscosity.
Further, when the curable resin composition of the present invention 1 or 2 is formed into a sheet shape and used as an adhesive epoxy resin sheet of the present invention 4, the naphthalene type epoxy resin usually contains an isomer. Therefore, since melting | fusing point is below normal temperature, while improving the softness | flexibility of a sheet | seat at normal temperature, it can make the sheet | seat before hardening hard to break and can also make a hardening rate quick.

  The naphthalene type epoxy resin is not particularly limited. For example, 1-glycidylnaphthalene, 2-glycidylnaphthalene, 1,2-diglycidylnaphthalene, 1,5-diglycidylnaphthalene, 1,6-diglycidylnaphthalene, 1 , 7-diglycidylnaphthalene, 2,7-diglycidylnaphthalene, triglycidylnaphthalene, 1,2,5,6-tetraglycidylnaphthalene and the like. These naphthalene type epoxy resins may be used alone or in combination of two or more.

The number of epoxy groups contained in the dicyclopentadiene-type epoxy resin or naphthalene-type epoxy resin is not particularly limited, but is preferably an average of 1 or more per molecule, more preferably per molecule. The average is 2 or more.
Here, the number of epoxy groups per molecule is the total number of epoxy groups in the dicyclopentadiene type epoxy resin or the total number of epoxy groups in the naphthalene type epoxy resin, or the total number of molecules of the dicyclopentadiene type epoxy resin or the naphthalene type. It can be obtained by dividing by the total number of molecules of epoxy resin.

  Although the molecular weight of the epoxy resin which has the said polycyclic hydrocarbon skeleton in a principal chain is not specifically limited, Preferably it is 500-1000. If the molecular weight of the epoxy resin having a polycyclic hydrocarbon skeleton in the main chain is less than 500, the mechanical strength, heat resistance, moisture resistance, etc. of the cured product of the curable resin composition may not be sufficiently improved, Conversely, if the molecular weight of the epoxy resin having a polycyclic hydrocarbon skeleton in the main chain exceeds 1000, the cured product of the curable resin composition may become too rigid and brittle.

  In the curable resin composition of the present invention 2, a dicyclopentadiene type epoxy resin and a naphthalene type epoxy resin may be used in combination as an epoxy resin having a polycyclic hydrocarbon skeleton in the main chain, and an epoxy resin composition comprising both In the thing, the compound which has another epoxy resin and an epoxy group may be contained as needed.

In the present invention 2, the solid polymer having a functional group that reacts with the above epoxy group in the present invention 1 is a polymer having an epoxy group and having an epoxy equivalent of 100 to 1000, and this polymer is used as the polymer. Since the cured product exhibits excellent flexibility, dimensional stability can be exhibited even after a load such as cold heat is applied.
That is, the cured product of the curable resin composition of the present invention 2 has excellent mechanical strength, excellent heat resistance, excellent moisture resistance, and the like derived from the epoxy resin having the polycyclic hydrocarbon skeleton in the main chain. Since it combines excellent flexibility derived from the above polymer having an epoxy group, it has excellent thermal cycle resistance, solder reflow resistance, dimensional stability, etc., and high adhesion reliability. Will be expressed.

  The polymer having an epoxy group may be any polymer having an epoxy group at the terminal and / or side chain (pendant position), and is not particularly limited. For example, an acrylic rubber having an epoxy group, a butadiene rubber having an epoxy group Bisphenol type high molecular weight epoxy resin, phenoxy resin having an epoxy group, acrylic resin having an epoxy group, urethane resin having an epoxy group, polyester resin having an epoxy group, and the like. An acrylic resin having an epoxy group is preferably used since the mechanical strength and heat resistance of the cured product of the curable resin composition of the second aspect of the present invention can be obtained. These polymer polymers having an epoxy group may be used alone or in combination of two or more.

  The above bisphenol-type high molecular weight epoxy resin alone can contain an epoxy group only at the terminal, and the distance between cross-linking points is greatly increased, so that the mechanical strength and heat resistance of the cured product of the curable resin composition are sufficiently high. Does not improve.

  In general, an acrylic resin (acrylic polymer) is often produced by a solution polymerization method using a solvent as a medium. In the solution polymerization method, when a high molecular weight acrylic resin is produced, the viscosity of the solution is increased. It is difficult to obtain a high molecular weight acrylic resin because it may rise extremely or may gel in some cases. Further, in the solution polymerization method, unreacted monomers are likely to remain, so that it is necessary to remove the residual monomers together with the solvent, and the manufacturing process becomes complicated.

  For example, when glycidyl methacrylate (GMA) is used as an acrylic monomer having an epoxy group and a large amount of GMA is added to another acrylic monomer and solution polymerization is performed, a relatively low molecular weight is caused by the cohesive force of the epoxy group itself. Only an acrylic resin having an epoxy group (less than 10000) can be obtained, and if an acrylic resin having a higher molecular weight epoxy group is to be obtained, the above extreme viscosity increase or gelation tends to occur.

On the other hand, when the acrylic resin having an epoxy group is produced by the suspension polymerization method using water or a non-solvent as a medium using the GMA or the like, an acrylic resin having a large amount of epoxy groups and having a high molecular weight epoxy group is used. A resin can be obtained. The acrylic resin having an epoxy group is a clean resin in which almost no monomer remains and can be easily separated from the polymerization system, thereby simplifying the manufacturing process.

  That is, the polymer having an epoxy group, preferably the acrylic resin having an epoxy group, used in the curable resin composition of the present invention 1 or 2 is preferably a polymer produced by a suspension polymerization method. By using a polymer having an epoxy group, preferably an acrylic resin having an epoxy group, produced by a suspension polymerization method, the cured product of the curable resin composition of the present invention 1 or 2 is more excellent in mechanical properties. It will exhibit strength and heat resistance.

  The polymer having an epoxy group, preferably an acrylic resin having an epoxy group, preferably has a weight average molecular weight of 10,000 or more, more preferably 100,000 or more. When the weight average molecular weight of the polymer having an epoxy group, preferably an acrylic resin having an epoxy group is less than 10,000, the film forming property of the curable resin composition becomes insufficient, and the cured product of the curable resin composition. The flexibility is not sufficiently improved.

  In the invention 2, the polymer having an epoxy group has an epoxy equivalent of 100 to 1,000. Preferably it is 200-700, More preferably, it is 300-600. If the epoxy equivalent of the polymer having an epoxy group is less than 100, the flexibility of the cured product of the curable resin composition may not be sufficiently improved. On the other hand, if the epoxy equivalent of the polymer polymer having an epoxy group exceeds 1000, the crosslink density decreases, and the mechanical strength and heat resistance of the cured product of the curable resin composition may be insufficient.

  In the curable resin compositions of the present inventions 2 and 3, if necessary, the glass transition temperature of the core contained in the curable resin composition of the present invention 1 is 20 ° C. or less, and the glass transition temperature of the shell is The rubber particles having a core-shell structure at 40 ° C. or higher may be contained in the curable resin composition of the second invention. Moreover, the said thermoplastic resin and thermosetting resin may contain.

  The curable resin compositions of the present inventions 2 and 3 may contain a filler as necessary.

  The curable resin compositions of the present invention 1 to 3 include, for example, an adhesion improver, a pH adjuster, an ion scavenger, a viscosity adjuster, a thixotropic agent, an antioxidant, and a heat stabilizer as necessary. One kind or two or more kinds of various additives such as a light stabilizer, an ultraviolet absorber, a colorant, a dehydrating agent, a flame retardant, an antistatic agent, an antifungal agent, an antiseptic, and a solvent may be added.

  Although it does not specifically limit as said adhesive improvement agent, For example, a silane coupling agent, a titanium coupling agent, an aluminum coupling agent etc. are mentioned, Especially, a silane coupling agent is used suitably. . These adhesion improvers may be used independently and 2 or more types may be used together.

  Although it does not specifically limit as said silane coupling agent, For example, an amino silane coupling agent, an imidazole silane coupling agent, an epoxy silane coupling agent, a ureido silane coupling agent, an isocyanate silane coupling agent, a vinyl silane cup Examples thereof include a ring agent, an acrylic silane coupling agent, and a ketimine silane coupling agent. Among them, an aminosilane coupling agent is suitably used from the viewpoint of curing speed and affinity with an epoxy resin. These silane coupling agents may be used alone or in combination of two or more.

  Although the addition amount of the said adhesive improvement agent is not specifically limited, It is 20 parts weight or less of adhesive improvement agent with respect to 100 weight part of curable resin compositions of this invention 1 or this invention 2. preferable. When the addition amount of the adhesion improver with respect to 100 parts by weight of the curable resin composition of the present invention 1 or 2 exceeds 20 parts by weight, when the curable resin composition is used as an adhesive epoxy resin sheet, for example, before curing. The strength and cohesive strength of the sheet may become too weak.

  Although it does not specifically limit as said pH adjuster, For example, alkaline fillers, such as acidic fillers, such as a silica, and calcium carbonate, etc. are mentioned. These pH adjusters may be used alone or in combination of two or more.

  The ion scavenger is not particularly limited as long as it can reduce the amount of ionic impurities. For example, aluminosilicate, hydrous titanium oxide, hydrous bismuth oxide, zirconium phosphate, phosphorus Examples include titanium oxide, hydrotalcite, ammonium molybdophosphate, hexacyanozinc, organic ion exchange resin, and the product name "IXE" series manufactured by Toa Gosei Co., Ltd., which is commercially available as an ion scavenger with excellent properties at high temperatures. It is done. These ion scavengers may be used alone or in combination of two or more.

  The addition amount of the ion scavenger is not particularly limited, but is preferably 10 parts by weight or less with respect to 100 parts by weight of the curable resin composition of the present invention 1 or the present invention 2. When the addition amount of the ion scavenger with respect to 100 parts by weight of the curable resin composition of the present invention 1 or 2 exceeds 10 parts by weight, the curing rate of the curable resin composition may be extremely slow.

  The manufacturing method of the curable resin composition of this invention 1-3 is not specifically limited, For example, well-known, such as a homodisper, a universal mixer, a Banbury mixer, a kneader, 2 rolls, 3 rolls, an extruder These various kneaders are used alone or in combination, each predetermined amount of each essential component, each predetermined amount of various components that may be contained, and one or two of various additives that may be added A desired curable resin composition is produced by uniformly kneading each predetermined amount of more than one kind under normal temperature, under heating, under normal pressure, under reduced pressure, under pressure, or under an inert gas stream. can do.

  In the curable resin compositions of the present invention 1 to 3 thus obtained, the pH of the extracted water when the elution component of the cured product of the curable resin composition is extracted with hot water at 110 ° C. is 5.0 or more and 8.5. It is preferable that it is less than 6.0, More preferably, it is 6.0 or more and less than 8.0.

  When the elution component of the cured product of the curable resin composition of the present invention 1 to 3 is extracted with hot water at 110 ° C., the pH of the extracted water is less than 5.0 or is 8.5 or more. Chlorine pulling reaction occurs when acid or alkaline substances flow out on or near the surface of the object, causing corrosion of electrode metals such as aluminum or copper, or by using acid generated by hydrolysis in the cured product as a catalyst. Ions may flow out and reliability may be impaired.

  It is preferable that the electrical conductivity of the extracted water when the elution component of the cured product of the curable resin composition of the present invention 1 to 3 is extracted with hot water at 110 ° C. is 100 μS / cm or less. Exceeding 100 μS / cm means that the electrical conductivity in the resin is increased particularly when placed under wet conditions, and the conductive connection using the curable resin compositions of the present invention 1 and the present invention 2 is performed. When used, leakage between electrodes or dielectric breakdown may occur.

  Moreover, it is preferable that the dielectric constant of the hardened | cured material of this invention 1-3 is 3.5 or less, and a dielectric loss tangent is 0.02 or less. If the dielectric constant exceeds 3.5 and the dielectric loss tangent exceeds 0.02, current transmission characteristics at high frequencies may be deteriorated.

  Applications of the curable resin compositions of the present invention 1 to 3 are not particularly limited. For example, the curable resin composition is processed into an adhesive epoxy resin paste, a conductive connection paste, a conductive connection sheet, etc., and is suitably used for fixing electronic materials. The Alternatively, the curable resin composition may be finished in a varnish shape, and formed into a thin film on a silicone wafer or the like by an application method such as spin coating, and used as an adhesive.

  You may add the flux agent to the curable resin composition of this invention 1-3. The flux agent is preferably a deactivating flux agent. Since the curable resin composition does not contain a filler having a large average particle size, it can be used substantially as a non-filler paste or non-filler sheet, and the cured product is also designed to have a neutral pH range. Therefore, it is suitable as a flux agent-containing paste or a flux agent-containing sheet for conductive connection.

  If the curable resin composition of this invention 1-3 is a pellet form, as sealing agents, such as a sealing agent for semiconductor packages, a sealing agent for QFN, a sealing agent for integral molding type CSP, etc., for example. Can be used. Further, if the curable resin composition is substantially a non-filler paste, it is directly applied and cured on a wafer with a metal post for rewiring and external electrical connection by screen printing or spin coating. The rewiring circuit can be sealed on the wafer by polishing. Furthermore, it can also be used as an overcoat agent on the wafer by coating directly on the wafer by screen printing.

Since the curable resin compositions of the present invention 1 to 3 inherently have adhesiveness, they can be easily formed into a sheet shape by the method described below to become the adhesive epoxy resin sheet of the present invention 4.
Therefore, it can be suitably used as an adhesive sheet for fixing a semiconductor chip. When the adhesive epoxy resin sheet of the present invention 4 is used to produce the curable resin compositions of the present invention 1 to 3, a curable resin composition is used, if necessary, using a viscosity modifier or a thixotropic agent. It can be easily obtained by forming a product into a sheet and finishing it.

  The method of obtaining the adhesive epoxy resin sheet of the present invention 4, that is, the method of molding the curable resin compositions of the present invention 1 to 3 into a sheet shape is not particularly limited. For example, an extrusion molding method using an extruder, curing A curable resin composition is diluted with a solvent to prepare a curable resin composition solution, and after casting the solution on a separator (release sheet), a solution casting method for drying the solvent, etc., among others, Since a high temperature is not required, the solution casting method is preferably used.

  The circuit board assembly of the present invention 5 comprises at least one circuit selected from the group consisting of a metal lead frame, a ceramic substrate, a resin substrate, a silicon substrate, a compound semiconductor substrate, and a glass substrate. A substrate and a semiconductor element (semiconductor chip, IC chip) are joined.

  The circuit board assembly of the present invention 6 includes at least one circuit board selected from the group consisting of a metal lead frame, a ceramic substrate, a resin substrate, a silicon substrate, a compound semiconductor substrate, and a glass substrate by the adhesive epoxy resin sheet of the present invention 4. A semiconductor element (semiconductor chip, IC chip) is joined.

  The circuit board assembly of the present invention 7 is obtained by using a glass epoxy substrate, a bismaleimide triazine substrate or a polyimide substrate as the resin substrate in the present invention 5 or 6.

  The curable resin composition of the present invention 2 is an epoxy resin in which an epoxy resin has a polycyclic hydrocarbon skeleton in the main chain, and a solid polymer having a functional group that reacts with an epoxy group is a polymer having an epoxy group. Since the epoxy equivalent is 100 to 1000, when the dicyclopentadiene type epoxy resin and the naphthalene type epoxy resin are used in combination, the cured product has excellent mechanical strength and flexibility in addition to the high adhesion reliability. -It can also exhibit dimensional stability and the like.

  The curable resin composition of the present invention 1 includes an epoxy resin, a polymer having a functional group that reacts with an epoxy group, and a solid alicyclic acid anhydride having a melting point of 110 ° C. or less as a curing agent for the epoxy resin. Therefore, while having storage stability at room temperature, it has immediate curing when cured by heating and the like, and the cured product has high adhesion reliability (heat resistance, moisture resistance, solder reflow resistance, (Cooling cycle etc.)

  The curable resin composition of the present invention 2 is an epoxy resin in which the epoxy resin has a polycyclic hydrocarbon skeleton in the main chain, and the solid polymer having a functional group that reacts with the epoxy group is a polymer having an epoxy group. In addition to the above effects, the cured product exhibits higher adhesion reliability because the epoxy equivalent is 100 to 1000.

  Since the curable resin composition of the present invention 3 uses the solid alicyclic acid anhydride represented by the general formula (1) as a curing agent in the curable resin composition of the present invention 1, the curable resin composition before the use is further used. The storage stability at room temperature is excellent, and the cured product exhibits high adhesion reliability.

Since the adhesive epoxy resin sheet of the present invention 4 is obtained by molding the curable resin composition according to any one of the present inventions 1 to 3 into a sheet shape, it exhibits high adhesion reliability.
Further, since it is in the form of a sheet, it is excellent in handleability and workability, and has adhesiveness, so that it can be suitably used as an adhesive sheet for fixing a semiconductor chip.

Since the circuit board assembly of the present invention 5 or 6 is produced using the curable resin composition of any of the present inventions 1 to 3 or the adhesive epoxy resin sheet of the present invention 4, high adhesion reliability (heat resistance) Properties, moisture resistance, solder reflow resistance, heat cycle resistance, etc.).
The circuit board assembly of the present invention 7 uses a glass epoxy substrate, a bismaleimide triazine substrate or a polyimide substrate as the resin substrate in the present invention 5 or 6, and thus exhibits high adhesion reliability.

  In order to explain the present invention in more detail, examples are given below, but the present invention is not limited to these examples.

In this example, the following raw materials were used unless otherwise specified.
1. Epoxy resin (1) Dicyclopentadiene type solid epoxy resin (trade name “EXA-7200HH”, manufactured by Dainippon Ink & Chemicals, Inc.)
(2) Naphthalene type liquid epoxy resin (trade name “HP-4032D”, manufactured by Dainippon Ink & Chemicals, Inc.)
(3) Bisphenol A type liquid epoxy resin (trade name “EP828”, manufactured by Japan Epoxy Resin Co., Ltd.)
2. Polymer having epoxy group (1) Epoxy-containing acrylic resin-a (trade name “Marproof G-2050M”, suspension polymerization method, epoxy equivalent: 340, weight average molecular weight: 200,000, glass transition temperature: 80 ° C., (Nippon Yushi Co., Ltd.)
(2) Epoxy group-containing acrylic rubber-b (99 parts by weight of ethyl acrylate and 1 part by weight of glycidyl methacrylate solution-polymerized in ethyl acetate by the thermal radical method, epoxy equivalent: 8000, weight average molecular weight: 200,000 Glass transition temperature: 10 ° C)

3. Curing agent for epoxy resin (1) 1-isopropyl-4-methylbicyclo- [2.2.2] -oct-5-ene-2,3-dicarboxylic acid anhydride (solid powder, melting point approx. 65 ° C)
(2) Trialkyltetrahydrophthalic anhydride (trade name “YH-306”, manufactured by Japan Epoxy Resin Co., Ltd., liquid)
(3) Benzophenone tetracarboxylic acid anhydride (trade name “BTDA” manufactured by Daicel Chemical Industries, solid, melting point 220 ° C.)
(4) Phthalic anhydride (manufactured by Nippon Shokubai Co., Ltd., solid, melting point 130 ° C)
4). Curing accelerator • Isocyanur-modified solid dispersion type imidazole (trade name “2MAOK-PW”, manufactured by Shikoku Chemicals)

5. Adhesion imparting agent-Imidazole silane coupling agent (trade name "SP-1000" Nikko Materials) 6. Filler ・ Surface-hydrophobized fumed silica (trade name “Leosil MT-10”, average particle size: 1 μm or less, manufactured by Tokuyama Corporation)
7). Stress relaxation imparting agent Core-shell type acrylic rubber particles having a hydroxyl group (trade name “STAPHYLOID AC-40 30”, manufactured by GANTZ Kasei Co., Ltd.)
8). Solvent ・ Ethyl acetate

Example 1
76 parts by weight of dicyclopentadiene type solid epoxy resin, 20 parts by weight of naphthalene type liquid epoxy resin, 4 parts by weight of acrylic resin having epoxy group, 40 parts by weight of dialkyl nadic acid anhydride derivative, 8 parts by weight of isocyanuric modified solid dispersion type imidazole , 2 parts by weight of aminosilane coupling agent, 4 parts by weight of surface-hydrophobized fumed silica, and 5 parts by weight of core-shell acrylic rubber particles having a hydroxyl group were dissolved in ethyl acetate, and the stirring speed was 3000 rpm using a homodisper type stirrer. Then, the mixture was stirred and mixed uniformly to prepare an ethyl acetate solution of a curable resin composition having a solid content of 50% by weight.

  Next, the ethyl acetate solution of the curable resin composition obtained above is dried on the surface of a 50 μm-thick polyethylene terephthalate (PET) sheet having a release treatment, and the thickness after drying is After coating using a bar coater so as to be 50 μm, it was dried at 110 ° C. for 3 minutes to prepare an adhesive epoxy resin sheet.

(Examples 2 to 4 and Comparative Examples 1 to 3)
The ethyl acetate solution of the curable resin composition (solid content 50 wt.%) Was the same as in Example 1 except that the composition of the adhesive epoxy resin sheet (curable resin composition) was changed to the composition shown in Table 1. %) And an adhesive epoxy resin sheet.

  1. Performance of adhesive epoxy resin sheets obtained in Examples 1 to 4 and Comparative Examples 1 to 3 (1. storage stability (gel fraction), 2) storage stability (glass transition temperature), 3) storage The stability (sheet appearance), 4. curing rate (gel fraction), 5. initial adhesive strength, 6. post-PCT adhesive strength, and 7. post-TCT adhesive strength) were evaluated by the following methods. The results are shown in Table 1.

1. Storage stability (gel fraction)
The adhesive epoxy resin sheet was left for a predetermined number of days in a room temperature 23 ° C. 50% atmosphere. Next, the sheet was immersed in room temperature ethyl acetate for 24 hours without being cured, and then the insoluble matter was filtered off and dried sufficiently. Then, the weight ratio of the cured product before and after the ethyl acetate immersion (weight after immersion / The weight before immersion) was determined, and the gelation rate (% by weight) was calculated.
2. Storage stability (glass transition temperature)
The adhesive epoxy resin sheet is allowed to stand for a predetermined number of days in an atmosphere of 23 ° C. and 50%. Next, the glass transition temperature (° C.) when the sheet was heated from −40 ° C. to 100 ° C. at 3 ° C./min was measured by DSC (differential calorimetry) with the sheet uncured.
3. Storage stability (sheet appearance)
The appearance of the adhesive epoxy resin sheet was visually evaluated for uniformity, sheet cracking, and discoloration.

4). Curing speed (gel fraction)
The adhesive epoxy resin sheet was heat-cured in an oven at 170 ° C. for 15 minutes. Next, after the cured product is immersed in ethyl acetate at room temperature for 24 hours, the insoluble matter is filtered off and sufficiently dried, and then the weight ratio of the cured product before and after immersion in ethyl acetate (weight after immersion / before immersion). Weight) was determined, and the gelation rate (% by weight) was calculated.

5. Initial adhesive force Adhesive epoxy resin sheet cut to 5 mm square was affixed on a glass epoxy substrate of FR-4, and a silicon chip having SiO ₂ passivation was affixed on it, pressed and adhered, A bonded body was prepared by heating and curing at 170 ° C. for 30 minutes. Next, jigs were attached to the upper and lower sides of the obtained joined body, and pulled up and down at a pulling speed of 5 mm / min, and the maximum breaking strength (N / 25 mm ² ) was determined and used as the initial adhesive strength.

6). Adhesive strength after 100 hours of PCT After the pressure cooker test (PCT) of the joined body produced in the same manner as in the case of measuring the initial adhesive strength was performed for 100 hours under the condition of 120 ° C.-85% RH, the joined body was taken out. . In the same manner as above, the maximum breaking strength (N / 25 mm ² ) was determined and used as the adhesive strength after 100 hours of PCT.
7). Adhesive strength after 500 cycles of TCT A thermal cycle test (TCT) of a joined body produced in the same manner as in the case of measuring the initial adhesive strength was performed 500 cycles by alternately repeating −45 ° C. × 10 minutes and 125 ° C. × 10 minutes. Thereafter, the joined body is taken out. In the same manner as described above, the maximum breaking strength (N / 25 mm ² ) was determined and used as the adhesive strength after TCT 500 cycles.

From Table 1, the adhesive epoxy resin sheets obtained in Examples 1 to 4 both have a gel fraction of the cured product of 100%, have excellent initial adhesive strength, and are bonded even after 100 hours of PCT. There was little decrease in power. However, in Example 4 using a solid polymer having an epoxy equivalent of more than 1000, although the storage stability was not a problem, the cross-linking density was lowered, so that the adhesive strength after TCT was slightly reduced.
In contrast, in Comparative Example 1 using the liquid acid anhydride curing agent, the storage stability at room temperature was poor, and the curable resin composition sheet was cracked and deteriorated. In Comparative Examples 2 and 3 using a solid acid anhydride having a high melting point, the glass transition temperature of the curable resin composition was high, so that it became brittle at room temperature immediately after production. Moreover, under the predetermined curing temperature conditions, curing was insufficient, and a decrease in adhesive strength after PCT and after TCT was also observed.
In addition, from the evaluation results of storage stability, the adhesive epoxy resin sheet of the present invention maintains the sheet properties without being embrittled even after 1 month at room temperature of 23 ° C., and maintains a usable state. It was shown to get.
In general, the storage stability of the curable resin composition is often required in practice, for example, that there is no deterioration for 2 weeks at room temperature during the production process of the circuit board, preferably 1 month at room temperature. Therefore, the storage stability of the adhesive epoxy resin sheet (curable resin composition) of the present invention sufficiently satisfies the practical characteristics.

The curable resin composition of the present invention is excellent in high adhesion reliability (heat resistance, moisture resistance, thermal cycle resistance, solder reflow resistance, etc.) after curing, and also has good mechanical strength and flexibility.・ Since dimensional stability can be expressed, bonding of various semiconductor elements and electronic parts including adhesive epoxy resin paste, adhesive epoxy resin sheet, conductive connection paste, conductive connection sheet, etc. And widely used for various industrial applications.

Claims (7)

  A curable resin composition comprising an epoxy resin, a solid polymer having a functional group that reacts with an epoxy group, and a curing agent for epoxy resin, wherein the curing agent for epoxy resin has a melting point of 110 ° C. or lower. A curable resin composition, which is an acid anhydride.   The epoxy resin is an epoxy resin having a polycyclic hydrocarbon skeleton in the main chain, and the solid polymer having a functional group that reacts with an epoxy group is a polymer having an epoxy group and has an epoxy equivalent of 100 to 1,000. The curable resin composition according to claim 1. The curable resin composition according to claim 1 or 2, wherein the solid alicyclic acid anhydride having a melting point of 110 ° C or lower is represented by the following general formula (1).

(R ¹ and R ² represent an alkyl group)   An adhesive epoxy resin sheet, wherein the curable resin composition according to any one of claims 1 to 3 is formed into a sheet shape.   By the curable resin composition according to any one of claims 1 to 3, a metal lead frame, a ceramic substrate, a resin substrate, a silicon substrate, a compound semiconductor substrate, and a glass substrate, at least one circuit board; A circuit board assembly comprising a semiconductor element and a semiconductor substrate.   5. The adhesive epoxy resin sheet according to claim 4, wherein at least one circuit board of a metal lead frame, a ceramic substrate, a resin substrate, a silicon substrate, a compound semiconductor substrate, and a glass substrate is bonded to the semiconductor element. A circuit board assembly characterized by comprising: The circuit board assembly according to claim 5 or 6, wherein the resin substrate is a glass epoxy substrate, a bismaleimide triazine substrate or a polyimide substrate.