JP2000169551A - Epoxy resin composition and its use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an epoxy resin composition which can give a cured product having low hygroscopicity and excellent cracking resistance and electrical properties by mixing an epoxy resin obtained from a phenol novolac resin with an ester-containing compound or an ester-containing resin curing agent and an essential cure accelerator being a phosphine oxide compound. SOLUTION: This composition comprises an epoxy resin of formula I, an at least difunctional ester-containing compound or ester-containing resin curing agent 10-100 mol% of the hydroxyl groups of which have been esterified with aromatic acyl groups, and a phosphine oxide compound of formula II. In the formulae, R1 to R6 are each H, a 1-10C linear, branched, or cyclic alkyl, a 6-10C aryl or an aralkyl; R7 is H, methyl or ethyl; and n is 0-100 (0-15 on the average). The amount of the phosphine oxide compound used is usually 0.001-25 wt.% based on the entire resin composition (the total amount of the epoxy resin and the curing agent).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device in which a semiconductor integrated circuit is sealed with an epoxy resin, and has various physical properties sufficient for the purpose, particularly, low hygroscopicity and melting of a resin composition. The present invention relates to an epoxy resin composition excellent in flowability and the like and excellent in crack resistance as a whole, and a cured product thereof. More specifically, a phenol novolak type epoxy resin as an epoxy resin, a compound or resin having an ester group as a curing agent, an epoxy resin composition comprising a combination of a curing accelerator that quickly reacts the ester group with an epoxy group, and It relates to the cured product.

[0002]

2. Description of the Related Art Conventionally, an integrated circuit (IC) or a large-scale integrated circuit (LSI) is protected from dust, dust, heat, moisture, light or malfunction due to light in an external atmosphere by a sealing material for protecting the same. Has been put to practical use. The sealing material has changed from a metal or ceramics material to a resin sealing material in recent years. At present, epoxy resin sealing material is mainly used. Particularly, an epoxy resin composition using a phenol resin as a curing agent is often used in view of a balance between cost and physical properties. Encapsulants using these epoxy resin compositions are required to improve not only mechanical properties but also the following problems.

[0003] That is, the subject is to absorb moisture in the outside air, so that when exposed to soldering conditions, it is exposed to high temperatures and causes cracks due to explosive vaporization of moisture. When the epoxy homopolymerization partially occurs, the hydroxyl groups of the phenol resin become excessive, and the moisture resistance and the electrical characteristics are poor, or the original epoxy-
In addition to the phenolic resin network, the presence of epoxy homopolymerized parts or excess phenolic resin parts may degrade the mechanical properties.Corrosion of metal parts of semiconductors and electric leakage due to mixing of free ions, especially halogen ions Etc. occur. Of these, the ionic impurities are problems of purification and purity of the epoxy resin, and are not essential, but the modification of the resin and the suppression of side reactions suppress the physical properties of the original epoxy resin composition. It is possible to pull out.

[0004] A material widely used as a semiconductor encapsulant recently is an orthocresol novolak type epoxy resin (trade name: EO) which is relatively inexpensive as a general-purpose grade.
CN-102S, manufactured by Nippon Kayaku Co., Ltd.) and a phenol novolak resin (trade name: BRG # 558, manufactured by Showa Polymer Co., Ltd., etc.), or a high-grade grade of biphenol or tetramethylbiphenol type Epoxy resin (trade name: YX4000, manufactured by Yuka Shell Epoxy Co., Ltd.)
And the like, and a phenol aralkyl resin (trade name: Millex XLC-225-4L, manufactured by Mitsui Chemicals, Inc.).

[0005] The former combination is characterized by high heat resistance and low cost by using an epoxy resin and a curing agent having a high functional group density, but has a high moisture absorption rate due to its high functional group density. Since the melt viscosity is high, there is a problem that the limit of the filler filling rate is low, and improvement thereof is required. The latter combination improves the workability and reduces the moisture absorption by combining a crystalline epoxy resin having a melting point around 100 ° C. and a low viscosity after melting with a phenol aralkyl resin having low moisture absorption and flexibility. Although it has the feature of improving the crack resistance due to the formation of an epoxy resin, there is a demand for improvement in terms of cost and heat resistance due to a decrease in crosslink density due to the use of an epoxy resin having a bifunctional component as a main component.

Further, regarding the moisture absorption of the resin, as long as the curing reaction is a reaction between an epoxy group and a hydroxyl group, it is a reaction that always generates a hydroxyl group as represented by the following reaction formula (7). However, the hydrophilicity increases due to the hydroxyl group, and there is a limit in reducing the overall moisture absorption even if the basic skeleton is made hydrophobic.

[0007]

Embedded image (In the formula, B represents an epoxy residue and D represents a phenol residue.) One method for solving this problem is to use an epoxy group and an ester as disclosed in Japanese Patent Application Laid-Open No. 62-53327 filed by Nishikubo et al. A radical reaction has been proposed. The publication discloses quaternary onium salts and crown ether complexes as preferable catalysts, and further discloses a paper disclosed in the same publication [Organic Synthetic Chemistry, Vol. 49, pp. 218-233 (1991); Addition reaction and its application to polymer synthesis], the yield when each catalyst is used as a unit reaction is shown. It shows that 91% of tetrabutylammonium chloride is the highest and the yield is generally low. In addition, when these quaternary onium salts and crown ether complexes remain contained in the resin used as the encapsulant for the semiconductor integrated circuit, they not only cause undesired results such as an electrical short circuit, but also cause Needless to say, it also causes corrosion of the metal parts that come into contact with it, causing serious defects as products.

On the other hand, in a general addition reaction between an epoxy resin and a phenol resin, phosphines such as trialkylphosphines and triarylphosphines, imidazoles, tertiary amines, and the like are used as catalysts. For immobilization, imidazoles and phosphines are often used. Of these, imidazoles have a reaction activity, but are liable to cause the epoxy homopolymerization which is a side reaction described above, and the above-mentioned problem is large. On the other hand, phosphines do not have these problems, but have a low curing rate. When imidazoles are used as a catalyst in epoxy / ester curing reactions, according to the above-mentioned literature by Nishikubo et al., The reaction yield of an addition reaction of an ester group to an epoxy group is about 50%, and the other is a single epoxy resin. Considering that it is a side reaction such as polymerization, it is not a catalyst that can obtain a sufficient cured product.

In addition, the present inventors have conducted further tests to find that when these imidazoles and phosphines are used as a curing catalyst, the ester formed by the aromatic acyl group in the present invention does not substantially cause a curing reaction of the epoxy resin. I understand. Specifically, in the range of 150 to 200 ° C., which is the temperature usually used for curing, it does not gel for 10 minutes or more,
In reality, this is a situation in which the resin composition flows out before a cured product is obtained (see a comparative example described later).

Further, the epoxy resin is ester-cured,
A method has been proposed in which 10 to 90% of a phenol resin is esterified and used as a curing agent for use as a sealing material for a semiconductor integrated circuit (Japanese Patent Application Laid-Open No. 9-235451). This method, when producing an ester resin,
The idea of leaving a part of the phenolic hydroxyl group of the phenolic resin, which is the raw material, to form a crosslinked part by the phenol part which is easy to react in the early stage of curing, and to make the ester group act on the epoxy group by the after-cure. It is based on.

However, the curing catalysts disclosed in the publication are phosphines, imidazoles and diazabicyclos, and the phosphines are an epoxy group and an ester group as shown in Comparative Examples of the present application (see Comparative Examples to be described later). In addition, imidazoles and diazabicyclos do not show sufficient curing catalytic activity against epoxy resin, and as is clear from the above-mentioned article by Nishikubo et al., Epoxy homopolymerization frequently occurs, and the molar ratio of epoxy group to curing agent functional group is increased. Adjustment is difficult, and physical properties are not preferable.

[0012]

DISCLOSURE OF THE INVENTION The present invention is an epoxy resin which is currently widely used as a general-purpose grade.
For phenol novolak epoxy resins, especially ortho-cresol novolak epoxy resins, a special curing catalyst (curing acceleration The present invention provides an epoxy resin composition for a semiconductor encapsulant, which has a low hygroscopicity and is excellent in crack resistance and electric characteristics, a cured product thereof, and a semiconductor device by combining the same.

[0013]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that the use of a phosphine oxide compound represented by the general formula (1) (formula 8) as a curing accelerator as an essential component allows the above-mentioned use. Finding that they can solve the problem,
The present invention has been completed.

[0014]

Embedded image (Wherein, R _{1 to} R ₆ represent a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms or a carbon atom having _{6 to 1} carbon atoms)
0 represents an aryl group or an aralkyl group, which may be the same or different. That is, the present invention comprises (1) a phosphine oxide compound represented by the general formula (1) as an essential component as a curing accelerator, and (A) a phenolic novolak resin obtained from a phenol novolak resin. An epoxy resin represented by 9),
(B) 10 mol% to 100 mol% of hydroxyl groups as a curing agent
Contains a bifunctional or more functional ester-containing compound or an ester-containing resin esterified by an aromatic acyl group.

[0015]

Embedded image (In the formula, R ₇ represents a hydrogen atom, a methyl group or an ethyl group, n representing the number of repeating units represents an integer of 0 to 100, provided that the average of n is in the range of 0 to 15.)

Further, the present invention provides a compound of the general formula (3) wherein (2) (B) an ester group-containing compound or an ester group-containing resin having two or more functional groups is obtained by esterifying a novolak resin.
A resin represented by the general formula (4) obtained by esterifying a phenol aralkyl resin, a resin represented by the following formula (10), and a general formula (5) obtained by esterifying a phenol-dicyclopentadiene resin: The epoxy resin composition according to (1), which is any one of the resin represented by the general formula (6) (Formula 13) obtained by esterifying a resin represented by the chemical formula 12) and a naphthol aralkyl resin.

[0017]

Embedded image (Wherein, R ₈ represents a hydrogen atom, a methyl group or an ethyl group, A represents a hydrogen atom or an aromatic acyl group, and the molar ratio of hydrogen atom / aromatic acyl group is 90/10 to 0/100.
Range. N indicating the number of repeating units is an integer of 0 to 100, and the average is in the range of 0 to 15. It should be noted that an average of the repeating unit n of 0 indicates a bisphenol compound. )

[0018]

Embedded image (Wherein, R ₉ represents a hydrogen atom, a halogen atom, a hydroxyl group, a linear, branched or cyclic alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 9 carbon atoms or a phenyl group; N ′ indicating the number of repeating units is 0 to
It represents an integer of 100, the average of which is in the range of 0-50. In addition, an average of the repeating unit n ′ of 0 indicates that the repeating unit is a bisphenol compound. A represents a hydrogen atom or an aromatic acyl group, and the hydrogen atom / aromatic acyl group molar ratio is 9
It is in the range of 0/10 to 0/100. )

[0019]

Embedded image (Wherein, R ₁₀ represents a hydrogen atom, a halogen atom, a hydroxyl group, a linear, branched or cyclic alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 9 carbon atoms or a phenyl group; N ″ indicating the number of repeating units is 0 to
It represents an integer of 50, the average of which is in the range of 0-15.
In addition, the average of the repeating unit n ″ is 0 when it is a bisphenol compound. A represents a hydrogen atom or an aromatic acyl group, and the molar ratio of hydrogen atom / aromatic acyl group is 90 /.
It is in the range of 10-0 / 100. )

[0020]

Embedded image (In the formula, n ″ indicating the number of repeating units is an integer of 0 to 50, and the average is in the range of 0 to 15. The average of repeating unit n ″ is 0, indicating that the compound is a bisphenol compound. A represents a hydrogen atom or an aromatic acyl group, and the molar ratio of hydrogen atom / aromatic acyl group is 90/10 to 0/1.
00 range. (3) (C) The organic and / or inorganic filler is (A +
B) For 100 parts by weight, 100 parts by weight or more, 190
The epoxy resin composition according to (1) or (2), which is contained in a range of 0 parts by weight or less, and (4) the epoxy resin composition according to any of (1) to (3), which is obtained by thermosetting. (5) A semiconductor device obtained by sealing a semiconductor integrated circuit using the epoxy resin composition according to any one of (1) to (3).

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The epoxy resin composition of the present invention comprises:
(A) an epoxy resin represented by the general formula (2) obtained from a phenol novolak resin as an epoxy resin, and a phosphine oxide compound represented by the general formula (1) as a curing accelerator, and B) An epoxy resin composition containing a bifunctional or more functional ester-containing compound or ester-containing resin as a curing agent. The epoxy resin composition of the present invention enables the epoxy group and the ester group to react quickly and selectively by using the phosphine oxide compound as a curing accelerator. An object of the present invention is to solve the problem and to provide a cured product having high mechanical properties, particularly low moisture absorption, excellent flexibility, and excellent crack resistance and electrical properties. Further, a resin composition obtained by adding an organic and / or inorganic filler to this resin composition has extremely excellent performance as a sealing material for a semiconductor integrated circuit. It is the first thing I found.

The phosphine oxide compound represented by the general formula (1), which is a curing accelerator used as an essential component in the epoxy resin composition of the present invention, will be described. In the general formula (1), all of the substituents R _{1 to} R ₆ may be the same or different, and may be a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms or a carbon number. 6 to 10 aryl groups or aralkyl groups.

Specific examples include a hydrogen atom; methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, 1-pentyl, 2-pentyl, 3-pentyl group, 2-methyl-1-butyl group, isopentyl group, tert-pentyl group, 3-methyl-2-butyl group, neopentyl group, n-
Hexyl group, 4-methyl-2-pentyl group, cyclopentyl group, cyclohexyl group, 1-heptyl group, 3-heptyl group, 1-octyl group, 2-octyl group, 2-ethyl-1-hexyl group, nonyl group or Straight chain such as decyl group,
A branched or cyclic alkyl group; an aryl group such as a phenyl group; an aralkyl group such as a toluyl group, a benzyl group, a 1-phenylethyl or a 2-phenylethyl group. Among them, preferred are an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group or a cyclohexyl group, and more preferred are a methyl group and an ethyl group. It is.

Such phosphine oxide compounds are described in G.
N.Koian etal.Journal of Generral Chemistry of
As described in The USSR, 55, 1453 (1985), it can be synthesized by reacting phosphorus oxytrichloride with three molecules of iminotrisamino (unsubstituted, monosubstituted, disubstituted) phosphorane. Furthermore, if purification is necessary, it can be purified by a commonly used method such as column chromatography, distillation, recrystallization and the like. The phosphine oxide compound thus obtained is usually a solid.

In the epoxy resin composition of the present invention, the use amount of the phosphine oxide compound as a curing accelerator is as follows:
0.001 to 25% (0. 0%) by weight based on the total epoxy resin composition (resin component: total of epoxy resin and curing agent).
001 to 25 g / 100 g), preferably 0.0
It is used in the range of 1 to 15%, more preferably 0.1 to 5%. When converted to a molar equivalent, 1.5 × 10 ⁻⁶ to 4.
5 × 10 ⁻² mol / 100 g, preferably 1.5 × 10 ⁻⁵
~ 2.5 × 10 ^-2 mol / 100 g, more preferably 1.
The range is from 5 × 10 ^{−4 to} 1.0 × 10 ⁻² mol / 100 g.

In the epoxy resin composition of the present invention, a known curing accelerator other than the phosphine oxide compound, for example, an imidazole such as 2-methylimidazole, a phosphine such as triphenylphosphine, or the like may be used. The oxide compound may be used in the range of 0.5% by weight to 500% by weight. The amount is 5
If it exceeds 00% by weight (5 equivalents), the characteristics of the present invention are lost.

In the epoxy resin composition of the present invention,
The component (A) is a phenol novolak type epoxy resin (hereinafter referred to as an epoxy resin) represented by the general formula (2) obtained from phenol novolak resins, and specifically, a phenol novolak resin or an ortho-cresol novolak resin. Epoxy compounds, for example, orthocresol novolak type epoxy resin is EOCN-10
It is commercially available from Nippon Kayaku Co., Ltd. under the trade name of 2S.

In the epoxy resin composition of the present invention,
The curing agent of the component (B) is a bifunctional or more functional ester-containing compound or ester-containing resin in which 10 to 100 mol% of hydroxyl groups are esterified with an aromatic acyl group. Specific examples of phenol resins that can be esterified are as follows.

That is, a novolak resin such as a phenol novolak resin or a cresol novolak resin represented by the general formula (3 ') (Formula 14); a residue obtained by removing a bisphenol compound from the novolak resin (a triphenol compound or more: Hereinafter abbreviated as VR); phenol aralkyl resins represented by general formula (4 ′) (Formula 15); general formula (5 ′)
A phenol-dicyclopentadiene copolymer resin (DPR resin) represented by the following formula:
And naphthol aralkyl resins represented by 7).

[0030]

Embedded image [Wherein, R ₈ and n have the same meaning as in formula (3). ]

[0031]

Embedded image [Wherein, R ₉ , m and n ′ have the same meaning as in the general formula (4). ]

[0032]

Embedded image [In the formula, R ₁₀ , m and n ″ have the same meaning as in the general formula (5).]

[0033]

Embedded image [Wherein, n ″ has the same meaning as in formula (6).]

As a method for esterifying these phenolic resins, known methods are used, and specific examples thereof are as follows. That is, the esterifying agent used when esterifying the above-mentioned hydroxyl group may be any of an organic carboxylic anhydride, an organic carboxylic halide, and an organic carboxylic acid. What is necessary is just to select suitably according to the characteristic of the esterifying agent according to the carbon number of the ester to be induced. Specific examples of this esterifying agent include benzoic anhydride, benzoic acid chloride, benzoic acid bromide, benzoic acid, o-methylbenzoic acid chloride, m-methylbenzoic acid chloride,
-Methylbenzoic acid chloride, o-methylbenzoic acid, m
-Methylbenzoic acid, p-methylbenzoic acid, 2,3-dimethylbenzoic acid, 2,4-dimethylbenzoic acid, 2,5-dimethylbenzoic acid, 2,6-dimethylbenzoic acid, 3,4-
Dimethylbenzoic acid, 3,5-dimethylbenzoic acid and the like can be mentioned. Among them, preferred are benzoic anhydride and benzoic chloride. These esterifying agents can be used alone or in combination of two or more.

The amount used is 10 mol% based on the number of hydroxyl groups.
The upper limit is not particularly limited, and when the esterification is sufficiently advanced by using the excess, the excess esterifying agent may be removed after the completion of the reaction. From the viewpoint of cost and the like, the molar ratio is preferably 10 times or less, preferably 5 times or less, more preferably 3 times or less with respect to the hydroxyl group.

The specific reaction varies depending on the type of the esterifying agent, but if each is mentioned, the reaction generally used may be used for the organic carboxylic anhydride. That is, after reacting an arbitrary amount of organic carboxylic anhydride to be esterified with respect to the hydroxyl group, the by-produced organic carboxylic acid and excess organic carboxylic anhydride are subjected to atmospheric distillation, vacuum distillation, water washing, and carbonate. The desired ester compound can be obtained by removal by an arbitrary method such as washing with a weak base water or a combination thereof. When performing partial esterification, an arbitrary amount based on hydroxyl groups, that is, 10 mol% or more of organic carboxylic acid anhydride is used in the present invention. The upper limit is not particularly limited as long as the solvent is used, but it may be used in an amount of 10 moles or less in consideration of economic efficiency and volumetric efficiency of the reaction. This amount is the same in the case of a reaction using an organic carboxylic acid described later.

In general, the esterification reaction is often carried out in the presence of an organic base which is inert to the reaction of pyridine, piperidine, triethylamine or the like.
When the epoxy resin composition of the present invention is used in the electric and electronic fields such as a sealing material for a semiconductor integrated circuit, it is necessary to prevent the nitrogen-containing organic base from remaining. For this reason, it is desirable to finally introduce a washing step. However, since the reaction proceeds sufficiently without using these organic bases, it is most desirable not to use an organic base in the present invention.

The reaction temperature ranges from 60 ° C. to 200 ° C., preferably from 80 ° C. to 180 ° C., particularly preferably 100 ° C.
It is desirable to be in the range of ℃ to 160 ℃. The reaction time largely depends on the type of the reactants and the reaction temperature, but is about 1 hour to 2 hours.
It is within a range of 5 hours, and in practice, it is desirable to determine the end point while tracking the disappearance of the esterifying agent, the disappearance of the hydroxyl group, and the like by high performance liquid chromatography, gas chromatography, or the like.

The solvent in the reaction may or may not be used. If the hydroxyl group-containing substance is sufficiently molten at the reaction temperature and the esterifying agent is a liquid, or if it is molten at the reaction temperature or if it dissolves in the resin and does not hinder the reaction, the reaction is carried out without solvent. Should be performed.

If a solvent is required, any solvent inert to the reaction can be used. Examples thereof include aromatic hydrocarbons such as benzene, toluene, xylene, chlorobenzene, o-dichlorobenzene and diphenyl ether; N, N-dimethylformamide,
Aprotic polar solvents such as N-dimethylacetamide, N-methyl-2-pyrrolidone, N, N-dimethyl-2-imidazolidinone, dimethylsulfoxide and sulfolane; and tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether and the like. Ethers; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and the like can be used alone or in any combination.

The reaction is carried out at normal pressure, pressure (in an autoclave),
Any of reduced pressure may be used, and the atmosphere of the reaction system is in air,
Any of inert gases such as nitrogen, argon and helium may be used, but preferably under a nitrogen atmosphere.

Next, the reaction when an organic carboxylic acid halide is used as the esterifying agent will be described.
Also in this case, a generally used technique can be used. That is, any amount of the organic carboxylic acid halide to be esterified with the hydroxyl group may be reacted. In this case, the by-produced hydrogen halide is trapped in the system in the presence of a required amount of a base inert to the reaction of pyridine, piperazine, triethylamine, or the like, and is discharged out of the system as a gas sequentially and quickly during the reaction. However, it is conceivable that trapping is carried out using water or an alkali trap installed outside the reaction system.However, for the reasons described above, hydrogen halide gas is used during the reaction to avoid contamination with nitrogen-containing compounds and ionic compounds. A method in which the compound is rapidly released from the system is preferred.
At this time, it is more preferable to carry out the reaction under a stream of a gas which is also inert to the reaction.

The amount of the organic carboxylic acid halide to be used is, when partial esterification is performed, an arbitrary amount based on hydroxyl groups, that is, an esterified product in which at least 10 mol% is esterified in the resin composition of the present invention. So 10 mol%
Using the above organic carboxylic acid halide, when completely esterifying, it is sufficient to use an equimolar or small excess with respect to the hydroxyl group, and the use of a large excess is not particularly limited, but economic efficiency, reaction efficiency, etc. Considering the volumetric efficiency and the complexity of the processing steps after the reaction, the molar ratio is preferably 10 times or less, preferably 5 times or less, more preferably 3 times or less with respect to the hydroxyl group.
It may be used in a range of not more than twice the mole. The reaction temperature, the use of a solvent in the reaction, and the form of the reaction may be in accordance with the case of the above-mentioned organic carboxylic anhydride.

When an organic carboxylic acid is used as the esterifying agent, the organic carboxylic acid anhydride may be substantially used, but an acid catalyst is required for the reaction. For example, mineral acids such as hydrochloric acid, sulfuric acid, phosphoric acid, and polyphosphoric acid, p
-Organic sulfonic acids such as toluenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, dimethylsulfonic acid, and diethylsulfonic acid, super strong acids represented by trifluoromethanesulfonic acid, and acidic ion exchange resins represented by alkanesulfonic acid type. Super strong acid type ion exchange resin represented by perfluoroalkanesulfonic acid type.

The amount of the superacid used is 0.00001 to 5% by weight, preferably 0.00.0% by weight, based on the weight of the raw material.
001 to 1% by weight, more preferably 0.001 to 0.1
In the range of 1 to 100% by weight, preferably 10 to 50% by weight in the case of ion exchange resins, and 0.01 to 10% by weight, preferably 0.1 to 5% by weight in other cases. Range. If the reaction time falls below this range, the reaction rate decreases, and the reaction is not completed in a practical reaction time. On the other hand, if it is larger than this range, the side reaction cannot be ignored, or it leads to an increase in cost including the complicated process of removing the catalyst.

The reaction has been described above with respect to the three types of esterifying agents. In any case, when it is necessary to obtain an esterified product having a higher degree of purification, a water washing step may be introduced after the completion of the reaction. Good. In that case toluene,
Washing may be performed using a water-washable solvent such as xylene, methyl isobutyl ketone, methyl ethyl ketone, or ethyl acetate until the washing wastewater is free of acidic components and ionic impurities.

In the present invention, the esterification ratio is in the range of 10 mol% to 100 mol%, preferably 50 mol% to 100 mol%, more preferably 80 mol% to 100 mol%, and furthermore Preferably 90 mol% to 1
It is in the range of 00 mol%.

The esterified product having an esterification ratio of 10 to 100 mol% obtained as described above can be used as a curing agent for an epoxy resin in the same manner as a conventional phenol resin. That is, by using a bifunctional or more functional epoxy resin as a curing agent, it can be used as a thermosetting resin in the same field as a conventional epoxy-phenol cured product. The most significant features of the cured product of the present invention are that the moisture absorption rate is greatly reduced as compared with a conventional epoxy-phenol cured product, and that the cured product is very flexible due to the effect of having an ester group. Furthermore, since a cured product is formed in a form in which the hydroxyl group is esterified with respect to the epoxy-phenol cured product in which a hydroxyl group is generated in the structure after curing, the electric characteristics are also improved.

Conventionally, phenolic resins have been frequently used as curing agents, especially in the field of sealing materials, but the improvement in performance has a great correlation with the improvement in low moisture absorption. When the water contained in the resin is suddenly exposed to a high temperature of 200 ° C. or more as in the case of IR reflow, it is vaporized at a stretch, generating a so-called steam explosive force. For this reason, cracks are generated, and various physical properties are adversely affected. In the worst case, the sealing material may be separated from the chip. The present invention contributes to solving this problem in terms of both low moisture absorption and crack resistance from the above-described features.

The mixing ratio of the epoxy resin and the curing agent is such that the ester group or the total of the ester group and the hydroxyl group is equivalent to 1 equivalent of the epoxy group, that is, 0.5 to 1.5 equivalent, preferably 0 to 1.5 equivalent of the active group to the epoxy group. It is in the range of 0.7 to 1.3 equivalents, and it is more preferable to adjust and use the equivalent ratio at which the optimum physical properties of the cured product are obtained. Each of the epoxy resin and the curing agent may be used alone or in combination.

In the epoxy resin composition of the present invention,
If necessary, as a component (C) in the epoxy resin composition,
Organic and / or inorganic fillers and other additives may be added. In particular, when used as a sealing material for semiconductor integrated circuits, organic and / or inorganic fillers are used to improve mechanical properties and reduce overall cost, and a coloring agent such as carbon black is used to prevent malfunction due to light. To
Further, it is desirable to use a release agent, a coupling agent, a flame retardant and the like.

The amount of the organic and / or inorganic filler used is 100% by weight based on 100 parts by weight of (A + B).
The content is in the range of 1900 parts by weight or less, preferably 250 parts by weight or more, more preferably 550 parts by weight or more from the viewpoint of moisture resistance and mechanical strength. Organic and / or inorganic fillers used include, for example, silica, alumina, silicon nitride, silicon carbide, talc, calcium silicate,
Examples thereof include powders such as calcium carbonate, mica, clay, and titanium white, and fibrous bodies such as glass fibers, carbon fibers, and aramid fibers. Among these, crystalline silica and / or fused silica are preferable for use as a sealing material. Further, in consideration of fluidity during molding of the resin composition, the shape is spherical or spherical and irregular. Mixtures are desirable.

In the epoxy resin composition of the present invention, it is preferable to add various additives in consideration of mechanical strength and heat resistance. For example, it is desirable to use a coupling agent in order to improve the adhesiveness between the resin and the inorganic filler, and examples of such a coupling agent include silane, titanate, aluminate, and zircoaluminate. Can be. Among them, a silane coupling agent is preferable, and a silane coupling agent having a functional group that reacts with an epoxy group is most preferable.

Examples of such a coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, N
-(2-aminomethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-anilinopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxy Silane and the like can be mentioned, and these can be used alone or in combination of two or more. It is desirable that these coupling agents are previously adsorbed on the surface of the inorganic filler or fixed by a reaction.

As a method for sealing a semiconductor integrated circuit using the epoxy resin composition of the present invention to produce a semiconductor device, low-pressure transfer molding can be said to be the most common method, but other methods, such as injection molding, can be used. , Compression molding, casting, etc., and special techniques such as using a solvent are also possible.

[0056]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. (Curing Agent Synthesis Example 1) A phenol aralkyl resin (trade name: Millex XLC-4L, average molecular weight (MW) 1385 (polystyrene equivalent)) was placed in a glass container equipped with a thermometer, a stirrer, a dropping funnel, and a reflux condenser. Hydroxyl equivalent 169 g / eq: 507 g (3 equivalents) manufactured by Mitsui Chemicals, Inc. was charged, and the internal temperature was raised to 125 ° C. The internal temperature was kept at the same temperature, and benzoic acid chloride 464.0 was added while stirring.
g (3.3 mol) was added dropwise over 4 hours. Then, 12
After performing the reaction for 2 hours while maintaining 5 ° C,
And aged at 150 to 155 ° C for 2 hours.
Hydrochloric acid by-produced by the reaction was quickly released out of the system by a nitrogen stream, and neutralized by an alkali trap. The resin obtained here was dissolved in 2500 g of toluene and washed with 2500 g of a 1% aqueous sodium carbonate solution. Thereafter, hot water was washed at 60 to 70 ° C. until the waste water became neutral, and then toluene was distilled off under conditions of a maximum of 150 ° C./5 mmHg to obtain 810 g of a resin in which hydroxyl groups were completely benzoylated. The melt viscosity of this resin (based on the ICI cone type melt viscosity type; the same applies hereinafter) is 4.8 poise at 125 ° C. and 150 ° C.
Is 1.3 poise, and the hydroxyl equivalent is 3000 g / eq.
This was the result (not detectable).

(Curing Agent Synthesis Example 2) A phenol aralkyl resin (trade name: MILEX XLC-4L, average molecular weight (MW) 1385 (polystyrene equivalent), hydroxyl equivalent 169 g / eq: Mitsui) was prepared in the same reactor as in Synthesis Example 1. Chemical Co., Ltd.
507 g (3 equivalents), 610.8 g of benzoic anhydride
(2.7 mol) was charged, and the mixture was stirred from the time when stirring became possible while gradually raising the temperature, and the temperature was raised to 125 ° C. in 2 hours. Thereafter, the reaction was performed for 2 hours while maintaining the temperature at 125 ° C., and the temperature was further raised to 150 ° C. After aging at 150 to 155 ° C for 2 hours, the mixture was cooled to 110 ° C, and 2500 g of methyl isobutyl ketone was charged into the reaction system to form a uniform solution. Benzoic acid by-produced by the reaction is neutralized with 2000 g of a 10% aqueous solution of sodium carbonate, washed with water at 60 to 70 ° C. until the waste water becomes neutral, and then methyl isobutyl ketone is treated at a maximum of 150 ° C./5 mmHg. The solvent was distilled off to obtain 783 g of a resin having a hydroxyl group of 90 mol% benzoylated. The melt viscosity of this resin is 5.
It was 1.5 poise at 2 poises and 150 ° C., and the hydroxyl equivalent was 1780 g / eq.

(Curing Agent Synthesis Example 3) A phenol aralkyl resin (trade name: Millex XLC-4) was placed in a glass container provided with a thermometer, a stirrer, a dropping funnel and a reflux condenser.
L, average molecular weight (MW) 1385 (in terms of polystyrene), hydroxyl equivalent 169 g / eq: manufactured by Mitsui Chemicals, Inc.) 50
7 g (3 equivalents) were charged, and the internal temperature was raised to 125 ° C. With the internal temperature kept at the same temperature, benzoic acid chloride 371.2 (2.64 mol) was added dropwise over 4 hours while stirring. Thereafter, the reaction was carried out for 2 hours while maintaining the temperature at 125 ° C., and then the temperature was further raised to 150 ° C. and aged at 150-155 ° C. for 2 hours. Hydrochloric acid by-produced by the reaction was quickly released out of the system by a nitrogen stream, and neutralized by an alkali trap. The resin obtained here was used in toluene 2500
g, washed with hot water at 60-70 ° C., and toluene was distilled off under conditions of a maximum of 150 ° C./5 mmHg to obtain 779 g of a resin having a hydroxyl group of 88% benzoylated. Melt viscosity of this resin (according to ICI cone type melt viscosity type).
The same applies hereinafter) is 4.9 poise at 125 ° C and 1. Poise at 150 ° C.
It was 4 poise and the hydroxyl equivalent was 1450 g / eq.

(Curing Agent Synthesis Example 4) A phenol aralkyl resin (trade name: MILEX XLC-4L, average molecular weight (MW) 1385 (polystyrene equivalent), hydroxyl equivalent 169 g / eq: Mitsui) was prepared in the same reactor as in Synthesis Example 1. Chemical Co., Ltd.
507 g (3 equivalents), 339.3 g of benzoic anhydride
(1.5 mol) was charged, and the mixture was stirred from the time when stirring became possible while gradually increasing the temperature, and the temperature was raised to 125 ° C. in 2 hours. Thereafter, the reaction was performed for 2 hours while maintaining the temperature at 125 ° C., and the temperature was further raised to 150 ° C. After aging at 150 to 155 ° C for 2 hours, the mixture was cooled to 110 ° C, and 2500 g of methyl isobutyl ketone was charged into the reaction system to form a uniform solution. Benzoic acid by-produced by the reaction is neutralized with 2,000 g of a 5% aqueous sodium carbonate solution, and then washed with hot water at 60 to 70 ° C. until the waste water becomes neutral, and then methyl isobutyl ketone is treated at a maximum of 150 ° C./5 mmHg. Then, 659 g of a resin having a hydroxyl group of 50 mol% benzoylated was obtained. The melt viscosity of this resin is 5.7 at 125 ° C.
The poise was 1.6 poise at 150 ° C., and the hydroxyl equivalent was 390 g / eq.

(Curing Agent Synthesis Example 5) The phenol aralkyl resin in Synthesis Example 1 was replaced with a phenol novolak resin (trade name: BRG # 558, average molecular weight (MW) 750 (in terms of polystyrene), hydroxyl equivalent 104 g / eq: Showa Polymer ( 618 g of a resin in which hydroxyl groups were completely benzoylated was obtained in the same manner except that 312 g (3 equivalents) manufactured by Co., Ltd.) was used. The melt viscosity of this resin is 4.9 poise at 125 ° C., 1
It is 1.5 poise at 50 ° C, and the hydroxyl equivalent is 3000 g.
/ Eq or more (not detectable).

(Curing Agent Synthesis Example 6) The phenol aralkyl resin in Synthesis Example 2 was replaced with a phenol novolak resin (trade name: BRG # 558, average molecular weight (MW) 750).
588 g of a resin having a hydroxyl group of 90 mol% benzoyl was obtained in the same manner as above except that 312 g (3 mol) of a hydroxyl group equivalent of 104 g / eq (manufactured by Showa Polymer Co., Ltd.) was used. The melt viscosity of this resin is 5.2 at 125 ° C.
The poison was 1.7 poise at 150 ° C., and the hydroxyl equivalent was 1134 g / eq.

(Curing Agent Synthesis Example 7) The phenol aralkyl resin in Synthesis Example 3 was replaced with a phenol novolak resin (trade name: BRG # 558, average molecular weight (MW) 750 (in terms of polystyrene), hydroxyl equivalent 104 g / eq: Showa Polymer ( 580 g of a resin having a hydroxyl group of 88% benzoylation was obtained in the same manner except that 312 g (3 equivalents) manufactured by K.K. The melt viscosity of this resin is 4.8 poise at 125 ° C., 1
It is 1.5 poise at 50 ° C. and the hydroxyl equivalent is 958 g /
eq.

(Curing Agent Synthesis Example 8) The phenol aralkyl resin in Synthesis Example 4 was replaced with a phenol novolak resin (trade name: BRG # 558, average molecular weight (MW) 750).
(In terms of polystyrene), a hydroxyl group equivalent of 104 g / eq: 412 g (3 equivalents) of a resin having a hydroxyl group of 50 mol% benzoylated in the same manner except that 312 g (3 equivalents) of Showa Polymer Co., Ltd. was used.
68 g were obtained. The melt viscosity of this resin is 5.5 poise at 125 ° C. and 1.8 poise at 150 ° C., and the hydroxyl equivalent is 2 poise.
It was 60 g / eq.

(Curing Agent Synthesis Example 9) The phenol aralkyl resin in Synthesis Example 1 was replaced with a phenol-dicyclopentadiene resin (trade name: DPR # 3000, average molecular weight (MW) 810 (in terms of polystyrene), hydroxyl equivalent 18)
866 g of a resin having completely benzoylated hydroxyl groups was obtained in the same manner except that 555 g (3 equivalents) of 5 g / eq: manufactured by Mitsui Chemicals, Inc. was used. The melt viscosity of this resin was 2.6 poise at 125 ° C. and 1.1 poise at 150 ° C., and the hydroxyl equivalent was 3000 g / eq or more (not detectable).

(Synthesis Example 10 of the Hardening Agent) The phenol aralkyl resin in Synthesis Example 2 was replaced with a phenol-dicyclopentadiene resin (trade name: DPR # 3000, average molecular weight (MW) 810 (polystyrene equivalent), hydroxyl equivalent 18)
(5 g / eq: Mitsui Chemicals, Inc.) 830 g of a resin having 90% benzoyl hydroxyl groups was obtained in the same manner except that 555 g (3 equivalents) was used. The melt viscosity of this resin was 3.4 poise at 125 ° C. and 1.6 poise at 150 ° C., and the hydroxyl equivalent was 1944 g / eq or more.

(Synthesis Example 11 of the Hardening Agent) The phenol aralkyl resin in Synthesis Example 3 was replaced with a phenol-dicyclopentadiene resin (trade name: DPR # 3000, average molecular weight (MW) 810 (in terms of polystyrene), hydroxyl equivalent 18)
822 g of a resin having a hydroxyl group of 88% benzoyl was obtained in the same manner except that 555 g (3 equivalents) of 5 g / eq: manufactured by Mitsui Chemicals, Inc. was used. The melt viscosity of this resin was 2.6 poise at 125 ° C. and 1.0 poise at 150 ° C., and the hydroxyl equivalent was 1,633 g / eq.

(Curing Agent Synthesis Example 12) The phenol aralkyl resin in Synthesis Example 2 was replaced with a phenol-dicyclopentadiene resin (trade name: DPR # 3000, average molecular weight (MW) 810 (polystyrene equivalent), hydroxyl equivalent 18)
5 g / eq: manufactured by Mitsui Chemicals, Inc.) 555 g (3 equivalents), and benzoic anhydride was changed to 271.4 g (1.2 mol) in the same manner as described above, except that the resin in which the hydroxyl group was 40% benzoylated was converted to 6
75 g were obtained. The melt viscosity of this resin is 3.4 poise at 125 ° C., 1.7 poise at 150 ° C., and the hydroxyl equivalent is 3 poise.
It was 49.9 g / eq.

(Curing Agent Synthesis Example 13) The phenol aralkyl resin in Synthesis Example 1 was replaced with a naphthol aralkyl resin (trade name: α-NX-3.2, average molecular weight (MW): 76).
0 (in terms of polystyrene), a hydroxyl group equivalent of 213 g / eq (manufactured by Mitsui Chemicals, Inc.) was replaced with 639 g (3 equivalents) of a resin in which hydroxyl groups were completely benzoylated.
g was obtained. The melt viscosity of this resin is 4.9 poise at 125 ° C. and 1.8 poise at 150 ° C., and the hydroxyl equivalent is 30.
It was not less than 00 g / eq (not detectable).

(Curing Agent Synthesis Example 14) The phenol aralkyl resin in Synthesis Example 2 was replaced with a naphthol aralkyl resin (trade name: α-NX-3.2, average molecular weight (MW): 76).
0 (polystyrene equivalent), a hydroxyl group equivalent of 213 g / eq: manufactured by Mitsui Chemicals, Inc.
37 g were obtained. The melt viscosity of this resin is 5.2 poise at 125 ° C and 2.1 poise at 150 ° C, and the hydroxyl equivalent is 2 poise.
It was 224 g / eq.

(Curing Agent Synthesis Example 15) The phenol aralkyl resin in Synthesis Example 3 was replaced by a naphthol aralkyl resin (trade name: α-NX-3.2, average molecular weight (MW): 76).
0 (polystyrene equivalent), hydroxyl group equivalent 213 g / eq: Mitsui Chemical Co., Ltd.) except that 639 g (3 equivalents) was used.
g was obtained. The melt viscosity of this resin is 5.0 poise at 125 ° C. and 1.9 poise at 150 ° C., and the hydroxyl equivalent is 18 poise.
67 g / eq.

(Curing Agent Synthesis Example 16) The phenol aralkyl resin in Synthesis Example 4 was replaced by a naphthol aralkyl resin (trade name: α-NX-3.2, average molecular weight (MW): 76).
0 (in terms of polystyrene), a hydroxyl group equivalent of 213 g / eq (manufactured by Mitsui Chemicals, Inc.) was replaced with 639 g (3 equivalents) of a resin having a hydroxyl group of 50 mol% benzoylated.
90 g were obtained. The melt viscosity of this resin is 5.2 poise at 125 ° C. and 2.1 poise at 150 ° C., and the hydroxyl equivalent is 4 poise.
It was 78 g / eq.

Example 1 Orthocresol novolak type epoxy resin (trade name: EOCN)
-102S, manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 210 g
/ Eq), and as a curing agent, 1 gram equivalent of the benzoylated phenol aralkyl resin of Synthesis Example 1 (ester equivalent: 273 g / eq = calculated value) was sufficiently melt-kneaded at 80 ° C. to obtain a uniform resin mixture. To this resin mixture, a phosphine oxide compound (PZO) in which all of R _{1 to} R ₆ of the general formula (1) are methyl groups is used as a curing accelerator.
0055 mol was added and kneaded at 50 ° C. for 1 minute to obtain a resin composition.

10 g of this resin composition was taken and 2 cm × 5
cm × 0.7mm, 150 ℃ → 185 ℃ /
After obtaining a cured product under the conditions of 5 min, 185 ° C./5 min, and 150 kg / cm ² , after-curing is performed under the conditions of 185 ° C./8 Hr (nitrogen atmosphere) to mold a resin plate that has been sufficiently cured. did. Using this resin plate, a simple crack test was performed. According to the method, a vertical half was cut with scissors, and the number of generated cracks was visually counted. As a result, no crack occurred.

Further, a filler and other additives were blended in the following ratio with the remaining 200 g of the resin composition, and the mixture was heated and kneaded with a roll to obtain a molding material for a sealing material. Inorganic filler: 720 parts by weight [Spherical fused silica (Halimic S-CO, manufactured by Micron Corporation) 50 parts by weight and amorphous fused silica (Fuselex RD-8, manufactured by Tatsumori Corporation) 50 parts by weight Mixture] Silane coupling agent: 62 parts by weight (SZ-6083, manufactured by Toray Dow Corning Silicone Co., Ltd.) Carnauba wax: 45 parts by weight Carbon black: 3 parts by weight Antimony oxide: 10 parts by weight

Using a part of this molding material, 150 ° C. → 1
85 ° C / 5min, 185 ° C / 5min, 150kg /
After obtaining a cured product under the condition of cm ² , 185 ° C./8 Hr
After-curing was applied under the condition of (nitrogen atmosphere) to sufficiently advance the curing. Each physical property was measured using this cured product. The results are shown in Table 1 (Table 1). Further, a test semiconductor device was prepared by low-pressure transfer molding using the same molding material, and a crack generation test using a solder bath was performed. The results are shown in Table 1 (Table 1). The symbols in the table represent the following. E: Esterification rate PZO: Phosphine oxide TPP: Triphenylphosphine UDI: 2-Undecylimidazole The gel time of the resin composition before kneading the rolls is 150 ° C.
(The same applies hereinafter).

(Examples 2 to 16) The curing agent in Example 1 was replaced with the resin obtained in Synthesis Examples 2 to 16, and an epoxy group / functional group (phenolic hydroxyl group + ester group) = 1
In the same manner, a resin composition was obtained at an equivalent ratio of / 1, and thereafter, all the same tests were performed. The results are shown in Table 1 (Tables 1 to 3).

Comparative Examples 1-4 Examples 1, 5, 9, 13
The curing accelerator used in the process is triphenylphosphine (TP
P) A resin composition was obtained in the same manner except that the amount was changed to 0.015 mol, and subsequent tests were carried out, but no cured product was obtained. The gel time is 2 at 150 ° C and 200 ° C.
The test was stopped for 0 minute because no gelation tendency was observed.

(Comparative Examples 5 to 8) Examples 1, 5, 9, and 13
The curing accelerator used in the above is 2-undecylimidazole (U
DI) A resin composition was obtained in the same manner except that the amount was changed to 0.015 mol, and subsequent tests were carried out, but no cured product was obtained. The gel time was also measured at 150 ° C. and 200 ° C. for 20 minutes, but the test was stopped because no gelation tendency was observed.

(Comparative Examples 9 to 12)
In the curing of the epoxy compound and the ester compound having the remaining hydroxyl groups in 14, the resin composition was obtained in the same manner except that the curing accelerator was changed to 0.015 mol of triphenylphosphine (TPP), and the subsequent tests were performed. However, a cured product was not obtained. The gel time was also measured at 150 ° C. and 200 ° C. for 20 minutes, but the test was stopped because no gelation tendency was observed.

(Comparative Examples 13 to 16)
Each test was carried out in the same manner as in Nos. 2 and 16 except that the curing accelerator was changed to 0.015 mol of triphenylphosphine (TPP) in the curing of the ester compound having the remaining hydroxyl group and the epoxy resin. Table 2 (Tables 5 and 6)
Shown in

(Comparative Examples 17 to 20) A phenol aralkyl resin (trade name: Millex XLC-4L, average molecular weight (MW) 1385 (in terms of polystyrene), hydroxyl equivalent 169 g / eq: Mitsui Chemicals, Inc.) )
Phenol novolak resin (trade name: BRG # 5)
58, average molecular weight (MW) 750 (polystyrene equivalent), hydroxyl equivalent 104 g / eq, manufactured by Yuka Shell Epoxy Co., Ltd., phenol-dicyclopentadiene resin (trade name: DPR # 5000, average molecular weight (MW) 81)
0 (polystyrene equivalent), hydroxyl equivalent 185 g / eq, manufactured by Mitsui Chemicals, Inc., α-naphthol aralkyl resin (trade name: α-NX-3.2, average molecular weight (MW) 760 (polystyrene equivalent), hydroxyl equivalent 213 g / eq, manufactured by Mitsui Chemicals, Inc.), and each test was carried out in the same manner except that the curing accelerator was replaced by 0.015 mol of triphenylphosphine (TPP). The results are shown in Table 2 (Table 6).

The test methods for various physical properties are as follows.・ Tg (glass transition temperature): TMA needle penetration method (Shimadzu T
Measured by MA-DRW DT-30. -Flexural strength and elastic modulus: according to JIS K-6911. Boiling water absorption: The weight increase after boiling for 2 hours in boiling water at 100 ° C. was measured. * V. P. S test: Test semiconductor device at 85 ° C, 8
After standing in a 5% constant temperature and humidity chamber for 168 hours, immediately
Fluorinert solution at 0 ° C (Sumitomo 3M Co., Ltd., F
C-70), and the number of semiconductors having cracks in the package resin was counted. The test value is shown as a fraction, the numerator is the number of cracked semiconductors, and the denominator is the number of subjects.

[0083]

[Table 1]

[0084]

[Table 2]

[0085]

[Table 3]

[0086]

[Table 4]

[0087]

[Table 5]

[0088]

[Table 6]

Although the examples have been described in detail, the phosphine oxide compound of the present invention is used as an essential curing accelerator, and an ester compound in which 10 to 100 mol% of hydroxyl groups are esterified is used as a curing agent. The epoxy resin composition described above has extremely low hygroscopicity and excellent flexibility as compared with a conventional epoxy resin-phenol resin cured product, and is very advantageous in crack resistance. For this reason, it turns out that it is excellent especially in a sealing material application of a semiconductor integrated circuit. In addition, when triphenylphosphine (TPP) which is a conventional curing accelerator is used, Comparative Example 1 is used.
As shown in Nos. 4 to 4, it can be seen that triphenylphosphine does not cause a curing reaction of a portion esterified by an aromatic acyl group. Further, as shown in Comparative Examples 9 to 12, even when an ester compound partially leaving a hydroxyl group is used, a cured product cannot be obtained. That is, it shows that the cured product is not a cured product because 90% or more of the ester portion is not involved in the curing. This indicates that an esterified curing agent and a phosphine oxide compound are essential factors for obtaining high physical properties as a sealing material in the present invention.

[0090]

The epoxy resin composition obtained by the present invention can be used in industrial fields where epoxy resin compositions have conventionally been used, but particularly when used as a sealing material for semiconductors, It provides a package having more excellent crack resistance than a cured epoxy resin-phenol resin.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tadahito Noboru 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Prefecture Inside (72) Inventor Uji Sangi 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Chemicals F term (reference) 4J036 AF06 DA05 DD07 FB06 FB07 FB08 JA07

Claims (5)

[Claims] 1. A curing accelerator of the general formula (1)
(A) an epoxy resin represented by the general formula (2) (formula 2) obtained from a phenol novolak resin; and (B) a phosphine oxide compound represented by the following formula:
An epoxy resin composition comprising, as a curing agent, a bifunctional or more functional ester-containing compound or an ester-containing resin in which 10 to 100 mol% of hydroxyl groups are esterified by an aromatic acyl group. Embedded image (Wherein, R _{1 to} R ₆ represent a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms or a carbon atom having _{6 to 1} carbon atoms)
0 represents an aryl group or an aralkyl group, which may be the same or different. ) (In the formula, R ₇ represents a hydrogen atom, a methyl group or an ethyl group, n representing the number of repeating units represents an integer of 0 to 100, provided that the average of n is in the range of 0 to 15.) 2. A resin represented by the general formula (3) or (3), wherein the ester-containing compound or the ester-containing resin (B) is obtained by esterifying a novolak resin, or a general formula (4) obtained by esterifying a phenol aralkyl resin. A) a resin represented by the general formula (5) obtained by esterifying a phenoldicyclopentadiene resin; and a resin represented by the general formula (6) obtained by esterifying a naphthol aralkyl resin. The epoxy resin composition according to claim 1, which is any one of the resins represented by the following formula: Embedded image (Wherein, R ₈ represents a hydrogen atom, a methyl group or an ethyl group, A represents a hydrogen atom or an aromatic acyl group, and the molar ratio of hydrogen atom / aromatic acyl group is 90/10 to 0/100.
Range. N indicating the number of repeating units is an integer of 0 to 100, and the average is in the range of 0 to 15. It should be noted that an average of the repeating unit n of 0 indicates a bisphenol compound. ) (Wherein, R ₉ represents a hydrogen atom, a halogen atom, a hydroxyl group, a linear, branched or cyclic alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 9 carbon atoms or a phenyl group; N ′ indicating the number of repeating units is 0 to
It represents an integer of 100, the average of which is in the range of 0-50. In addition, an average of the repeating unit n ′ of 0 indicates that the repeating unit is a bisphenol compound. A represents a hydrogen atom or an aromatic acyl group, and the hydrogen atom / aromatic acyl group molar ratio is 9
It is in the range of 0/10 to 0/100. ) (Wherein, R ₁₀ represents a hydrogen atom, a halogen atom, a hydroxyl group, a linear, branched or cyclic alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 9 carbon atoms or a phenyl group; N ″ indicating the number of repeating units is 0 to
It represents an integer of 50, the average of which is in the range of 0-15.
In addition, when the average of the repeating unit n ″ is 0, it indicates that the compound is a bisphenol compound. A represents a hydrogen atom or an aromatic acyl group, and the molar ratio of the hydrogen atom / aromatic acyl group is 90 /.
It is in the range of 10-0 / 100. ) (In the formula, n ″ indicating the number of repeating units is an integer of 0 to 50, and the average is in the range of 0 to 15. The average of repeating unit n ″ is 0, indicating that the compound is a bisphenol compound. A represents a hydrogen atom or an aromatic acyl group, and the molar ratio of hydrogen atom / aromatic acyl group is 90/10 to 0/1.
00 range. ) (C) 100 parts by weight or more of an organic and / or inorganic filler per 100 parts by weight of (A + B);
3. The epoxy resin composition according to claim 1, which is contained in an amount of 900 parts by weight or less. 4. An epoxy resin cured product obtained by thermally curing the epoxy resin composition according to claim 1. 5. A semiconductor device obtained by sealing a semiconductor integrated circuit with the epoxy resin composition according to claim 1.