JP2002080696A - Sealing epoxy resin molding material and electronic part device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing epoxy resin molding material having good reflow cracking resistance even when a lead-free solder requiring high temperature reflowing of >=260 deg.C is used and, at the same time, having excellent moldability such as flowability and curability, and an electronic part device having an element sealed with this sealing epoxy resin molding material for sealing. SOLUTION: The sealing epoxy resin molding material for electronic part devices which uses a lead-free solder comprises (A) an epoxy resin, (B) a curing agent, (C) a curing accelerator, (D) an inorganic filler, and (E) a plasticizer as the essential components and has a flexural modulus at 260 deg.C of a molded article of <=550 MPa. The electronic part device has an element sealed with this sealing epoxy resin molding material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is excellent in moldability such as fluidity and curability and heat resistance, and has good reflow crack resistance even when a lead-free solder requiring high temperature reflow at 260 ° C. or higher is used. The present invention relates to an epoxy resin molding material for sealing, and an electronic component device provided with an element sealed with the epoxy resin molding material for sealing.

[0002]

2. Description of the Related Art Conventionally, epoxy resin molding materials have been widely used in the field of sealing electronic components such as transistors and ICs. The reason for this is that the epoxy resin is balanced in various properties such as electrical properties, moisture resistance, heat resistance, mechanical properties, and adhesiveness to insert products. In particular, a combination of an ortho-cresol novolak type epoxy resin and a phenol novolak curing agent has an excellent balance between them, and has become a mainstream base resin for molding materials for sealing. In recent years, with the increase in the density of electronic components mounted on printed wiring boards, electronic component devices have become the mainstream, instead of the conventional pin insertion type, and are now surface-mounted type packages. Surface-mounted ICs, LSIs, etc. are thin and small packages in order to increase the mounting density and lower the mounting height. It has become very thin.
Furthermore, these packages are different in mounting method from the conventional pin insertion type. That is, in the pin insertion type package, the pins are inserted into the wiring board and then soldered from the back surface of the wiring board, so that the package is not directly exposed to a high temperature. However, since the surface mount type package is temporarily fixed to the surface of the wiring board and processed by a solder bath or a reflow device, it is directly exposed to the soldering temperature. As a result, when the package absorbs moisture, the moisture absorbs rapidly expands during soldering, causing the package to crack. At present, this phenomenon is a major problem related to the surface mount type package. On the other hand, from the viewpoint of environmental protection, a lead component contained in a conventionally used solder has been regarded as a problem. At present, most of electronic component waste is made of synthetic resin such as a printed circuit board and metal such as a semiconductor and a frame. If acid rain falls there, lead elutes from the solder in the electronic component waste into groundwater, and if the groundwater is used for drinking water, it may have a bad effect on the human body. Ingredients are becoming a problem.

[0003]

SUMMARY OF THE INVENTION To solve the above problem,
Various lead-free solders (lead-free solders) have been proposed, but lead-free solders having the same melting point as conventional lead-containing solders (Sn-Pb eutectic composition) are not sufficient in connection reliability. Performance has not been obtained.
JP-A-323495, JP-A-9-85484, JP-A-9-253882, JP-A-11-33775
JP-A-11-221694 and the like. Also,
Lead-free solders that are currently considered to be promising in terms of connection reliability include Sn (94.25% by weight) -Ag (2% by weight) -Bi (3% by weight) -Cu (0.75% by weight) composition. And Sn (95.75% by weight) -Ag (3.5% by weight) -Cu (0.75% by weight) composition solder, and these have a melting point of 210 to 220 ° C. and a conventional lead content. Since the melting point of the solder is higher than the melting point of 183 ° C. by 30 to 40 ° C., the reflow temperature at the time of mounting is 260 to 275 °
° C, and there is a demand for a molding compound for sealing to have an even higher reflow crack resistance. The present invention has been made in view of such circumstances, and has good reflow crack resistance even when a lead-free solder requiring high-temperature reflow of 260 ° C. or more is used, and has moldability such as fluidity and curability. It is an object of the present invention to provide an epoxy resin molding material for sealing which is excellent in the above, and an electronic component device provided with an element sealed thereby.

[0004]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, have added a plasticizer to increase the flexural modulus at 260.degree.
By setting the ratio to a or less, an epoxy resin molding material for sealing excellent in reliability was obtained, and it was found that the above object could be achieved. Thus, the present invention was completed.

That is, the present invention provides a molded article comprising (1) (A) an epoxy resin, (B) a curing agent, (C) a curing accelerator, (D) an inorganic filler and (E) a plasticizer as essential components. Of 26
The sealing epoxy resin molding material having a flexural modulus at 0 ° C. of 550 MPa or less, (2) the sealing epoxy resin molding material according to (1), further comprising (F) a low stress agent; 3) The epoxy resin molding material for sealing according to the above (1) or (2), wherein the blending amount of the plasticizer (E) is 2 to 18% by weight based on the epoxy resin (A).
(E) The sealing epoxy resin molding material according to any one of the above (1) to (3), wherein the plasticizer contains an epoxy-based plasticizer and / or a phosphate-based plasticizer; The epoxy resin molding material for sealing according to the above (4), which is epoxidized soybean oil, and the epoxy resin molding material for sealing according to the above (4) or (5), wherein the phosphate plasticizer is a phosphate compound. The material, (7) the epoxy resin molding material for sealing according to (6), wherein the phosphate compound is a compound represented by the following general formula (I):

Embedded image (Here, R represents an alkyl group having 1 to 4 carbon atoms, all of which may be the same or different. Ar represents a divalent organic group having a substituted or unsubstituted aromatic ring, and m represents 0 (8) (8) (F) (F) wherein the stress reducing agent is a rubber particle.
The epoxy resin molding material for sealing according to any one of (7) and (9) wherein the epoxy resin (A) is an epoxy resin represented by the following general formula (II) and an epoxy resin represented by the following general formula (III). An epoxy resin molding material for sealing according to any one of the above (1) to (8),

Embedded image (Here, R represents a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 5 carbon atoms, and n represents an integer of 0 to 10.)

Embedded image (Here, R ^{1 to} R ⁴ are selected from a hydrogen atom and a substituted or unsubstituted monovalent hydrocarbon group having 1 to 5 carbon atoms, all of which may be the same or different. (10) The compounding weight ratio of the epoxy resin represented by the general formula (II) to the epoxy resin represented by the general formula (III) is 2:
The epoxy resin molding material for sealing according to the above (9), which is 8 to 8: 2, and the curing agent (11) (B) is represented by the following general formula (I)
The epoxy resin molding material for sealing according to any one of the above (1) to (10), which comprises a phenolic resin represented by V), and

Embedded image (Here, R represents a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, and n represents an integer of 0 to 8.) (12) The above (1) to (11) The present invention relates to an electronic component device provided with an element sealed with the sealing epoxy resin molding material according to any one of the above.

[0006]

DETAILED DESCRIPTION OF THE INVENTION (A) used in the present invention
The epoxy resin is not particularly limited in those commonly used in epoxy resin molding material for sealing, for example, phenol novolak type epoxy resin, phenols such as ortho-cresol novolak type epoxy resin, cresol, xylenol, Phenols such as resorcinol, catechol, bisphenol A and bisphenol F and / or naphthols such as α-naphthol, β-naphthol and dihydroxynaphthalene and compounds having an aldehyde group such as formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde and salicylaldehyde; Epoxidized novolak resin obtained by condensation or co-condensation under acidic catalyst, bisphenol A, bisphenol F, bisphenol S, alkyl-substituted or unsubstituted Diglycidyl ethers such as biphenol, diglycidyl ethers of stilbene phenols, phthalic acid, glycidyl ester type epoxy resins obtained by the reaction of epichlorohydrin with polybasic acids such as dimer acid, diaminodiphenylmethane, polyamines such as isocyanuric acid and epichlorohydrin Glycidylamine type epoxy resin obtained by the reaction, epoxidized cocondensation resin of dicyclopentadiene and phenols,
Epoxy resin having naphthalene ring, epoxidized naphthol aralkyl resin, trimethylolpropane type epoxy resin, terpene modified epoxy resin, linear aliphatic epoxy resin obtained by oxidizing olefin bond with peracid such as peracetic acid, alicyclic Group epoxy resins, and these may be used alone or in combination of two or more. Above all, it is preferable to use a novolak-type epoxy resin represented by the following general formula (II) and a stilbene-type epoxy resin represented by the following general formula (III) in combination from the viewpoint of compatibility between moldability and reflow crack resistance.

[0007]

Embedded image (Here, R represents a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 5 carbon atoms, and n represents an integer of 0 to 10.)

Embedded image (Here, R ^{1 to} R ⁴ are selected from a hydrogen atom and a substituted or unsubstituted monovalent hydrocarbon group having 1 to 5 carbon atoms, all of which may be the same or different. Indicates an integer.)

The novolak type epoxy resin represented by the general formula (II) includes, for example, phenol novolak epoxy resin, cresol novolak epoxy resin and the like, and among them, orthocresol novolak epoxy resin is preferable.

The stilbene-type epoxy resin represented by the general formula (III) can be obtained by reacting stilbene-based phenols as raw materials with epichlorohydrin in the presence of a basic substance. Examples of the stilbene-based phenols as the raw material include, for example, 3-t-butyl-4,4 '
-Dihydroxy-3 ', 5,5'-trimethylstilbene, 3-tert-butyl-2,4'-dihydroxy-3',
5 ', 6-trimethylstilbene, 3-t-butyl-
4,4'-dihydroxy-3 ', 5', 6-trimethylstilbene, 2,2'-dihydroxy-3,3 ', 5
5'-tetramethylstilbene, 4,4'-dihydroxy-3,3 ', 5,5'-tetramethylstilbene,
4,4'-dihydroxy-3,3'-di-t-butyl-
5,5′-dimethylstilbene, 4,4′-dihydroxy-3,3′-di-t-butyl-6,6′-dimethylstilbene, 2,2′-dihydroxy-3,3′-di-t
-Butyl-6,6'-dimethylstilbene, 2,4'-
Dihydroxy-3,3'-di-t-butyl-6,6'-
Dimethylstilbene and the like, among which 3-tert-butyl-4,4'-dihydroxy-3 ', 5,5'-trimethylstilbene and 4,4'-dihydroxy-3,
3 ', 5,5'-Tetramethylstilbene is preferred.
These stilbene phenols can be used alone or
A combination of more than one species may be used. The stilbene type epoxy resin represented by the general formula (III) used in the present invention may be used alone or in combination of two or more.

When a novolak type epoxy resin represented by the general formula (II) and a stilbene type epoxy resin represented by the general formula (III) are used, the compounding amount thereof is (A) the total amount of the epoxy resin from the viewpoint of reflow crack resistance. Is preferably 40% by weight or more, more preferably 60% by weight or more. The compounding weight ratio of the novolak type epoxy resin represented by the general formula (II) and the stilbene type epoxy resin represented by the general formula (III) (II)
/ (III) is preferably 2/8 to 8/2, and 3/7 to 7
/ 3 is more preferred, and 4/6 to 6/4 is even more preferred. If the proportion of the novolak type epoxy resin represented by the general formula (II) is too large, the reflow crack resistance tends to decrease, and if the proportion of the stilbene type epoxy resin represented by the general formula (III) is too large, molding is performed. Properties tend to decrease.

[0011] The curing agent (B) used in the present invention is not particularly limited and is generally used in epoxy resin molding materials for encapsulation.
Phenols such as cresol, resorcin, catechol, bisphenol A, bisphenol F, phenylphenol, aminophenol and / or α-naphthol;
Resin obtained by condensing or co-condensing naphthols such as β-naphthol and dihydroxynaphthalene with compounds having an aldehyde group such as formaldehyde, and synthesized from phenols and dimethoxyparaxylene or bis (methoxymethyl) biphenyl Phenol
Examples thereof include aralkyl resins, aralkyl-type phenol resins such as naphthol / aralkyl resins, and terpene-modified phenol resins. These may be used alone or in combination of two or more. Among them, phenol-aralkyl resins represented by the following general formula (IV) are preferred from the viewpoint of reflow crack resistance, and those in which R in the formula (IV) is a hydrogen atom and n is 0 to 8 on average are more preferable. preferable. When the phenol-aralkyl resin represented by the general formula (IV) is used, its blending amount is preferably at least 30% by weight, more preferably at least 50% by weight, based on the total amount of the curing agent (B). % By weight or more is more preferable.

[0012]

Embedded image (Here, R represents a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, and n represents an integer of 0 to 8.)

In the present invention, the mixing ratio of (A) the epoxy resin and (B) the curing agent is determined by the ratio of the hydroxyl equivalent of the entire curing agent to the epoxy equivalent of the entire epoxy resin (curing amount) in order to suppress the respective unreacted components. Number of hydroxyl groups in the agent /
(The number of epoxy groups in the epoxy resin) is preferably set in the range of 0.5 to 2, more preferably 0.7 to 1.5. In particular, in order to obtain a molding material having excellent moldability and reflow crack resistance, this ratio is more preferably set in the range of 0.8 to 1.2.

The curing accelerator (C) used in the present invention is not particularly limited, and is generally used in molding epoxy resin molding materials.
Diazabicyclo [5.4.0] -7-undecene, 1,
5-diazabicyclo [4.3.0] -5-nonene, 5,
6-dibutylamino-1,8-diazabicyclo [5.
4.0] -7-undecene and the like, and maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone,
2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-
Compounds having intramolecular polarization obtained by adding quinone compounds such as benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, phenyl-1,4-benzoquinone, and compounds having a π bond such as diazophenylmethane and phenol resin. , Benzyldimethylamine, triethanolamine,
Tertiary amines such as dimethylaminoethanol and tris (dimethylaminomethyl) phenol and derivatives thereof, imidazoles such as 2-methylimidazole, 2-phenylimidazole and 2-phenyl-4-methylimidazole and derivatives thereof, tributyl Phosphine,
Organic phosphines such as methyldiphenylphosphine, triphenylphosphine, tris (4-methylphenyl) phosphine, diphenylphosphine, and phenylphosphine; and phosphines such as maleic anhydride, the above quinone compounds, diazophenylmethane, and π such as phenol resin. Phosphorus compound having intramolecular polarization obtained by adding a compound having a bond, tetraphenylphosphonium tetraphenylborate, triphenylphosphine tetraphenylborate, 2-ethyl-4-methylimidazole tetraphenylborate, N-methylmorpholine tetraphenyl And tetraphenylboron salts such as borate and derivatives thereof. These curing accelerators may be used alone or in combination of two or more.

The amount of the curing accelerator (C) is not particularly limited as long as the curing acceleration effect is achieved, but is preferably 0.005 to 2% by weight based on the molding epoxy resin molding material. , 0.01 to 0.5% by weight. 0.
If the amount is less than 005% by weight, the curability in a short time tends to be poor. If the amount exceeds 2% by weight, the curing speed tends to be too fast to obtain a good molded product.

The inorganic filler (D) used in the present invention is blended into the epoxy resin molding compound for sealing in order to absorb moisture, reduce the coefficient of linear expansion, improve thermal conductivity and improve strength. , Fused silica, crystalline silica, alumina, zircon, calcium silicate, calcium carbonate, potassium titanate, silicon carbide, silicon nitride, aluminum nitride, boron nitride, beryllia, zirconia, zircon, fosterite, steatite, spinel, mullite, titania And the like, or spherical beads and glass fibers thereof. Further, examples of inorganic fillers having a flame-retardant effect include composite metal hydroxides such as aluminum hydroxide, magnesium hydroxide, zinc borate, zinc molybdate, and a composite hydroxide of magnesium and zinc. These inorganic fillers may be used alone or in combination of two or more. Among the above-mentioned inorganic fillers, fused silica is preferred from the viewpoint of reducing the coefficient of linear expansion, and alumina is preferred from the viewpoint of high thermal conductivity, and the filler shape is spherical from the viewpoint of fluidity during molding and mold abrasion. Is preferred. (D) The compounding amount of the inorganic filler is preferably 70% by weight or more based on the molding epoxy resin molding material from the viewpoints of moldability, hygroscopicity, reduction of linear expansion coefficient and improvement in strength.
~ 95% by weight is more preferred. If it is less than 70% by weight, reflow crack resistance tends to decrease, and if it exceeds 95% by weight, fluidity tends to be insufficient.

The plasticizer (E) used in the present invention is not particularly limited. Examples thereof include ditridecyl phthalate, di-2-ethylhexyl phthalate, dinormal octyl phthalate, diisononyl phthalate, and dinormal decyl phthalate. Fatty acid plasticizers, fatty acid plasticizers such as butyl oleate, diethyl succinate and dibutyl sebacate, adipates such as dimethyl adipate, dibutyl adipate, diisobutyl adipate, di-2-ethylhexyl adipate, diisodecyl adipate and dibutyl diglycol adipate Plasticizers, trimellitate-based plasticizers such as tri-2-ethylhexyl trimellitate, trinormal octyl trimellitate, triisodecyl trimellitate, and trinormal octyl trimellitate; Polyester plasticizers such as 1,3-butanediol adipate, epoxy plasticizers such as epoxidized soybean oil and epoxidized linseed oil, trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri-2-ethylhexyl phosphate, tributoxyethyl Phosphate ester compounds such as phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, 2-ethylhexyl diphenyl phosphate, and compounds represented by the following general formula (I) Phosphate-based plasticizer such as a compound having a bond), and these may be used alone or in combination of two or more.

[0018]

Embedded image (Here, R represents an alkyl group having 1 to 4 carbon atoms, all of which may be the same or different. Ar represents a divalent organic group having a substituted or unsubstituted aromatic ring, and m represents 0 Represents an integer of 2 to 2)

Among them, from the viewpoint of moisture resistance reliability and moldability, epoxy plasticizers such as epoxidized soybean oil and epoxidized linseed oil, and tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, Phosphate plasticizers such as -ethylhexyl diphenyl phosphate and phosphate compounds such as the compounds represented by the above general formula (I) are preferred, and epoxidized soybean oil and phosphate ester compounds are more preferred. As the phosphate compound, a compound represented by the above general formula (I) is preferable. Epoxidized soybean oil is more preferred from the viewpoint of appearance due to exudation from a molded article. When an epoxy-based plasticizer and / or a phosphate-based plasticizer is used, the amount thereof is preferably 30% by weight or more, more preferably 50% by weight or more, based on the total amount of the (E) plasticizer. % By weight or more is more preferable. Commercial products can be used as the epoxidized soybean oil,
For example, Asahi Denka Kogyo Co., Ltd. trade name Adekaiser O-
130P and Kapox S-6, trade name of Kao Corporation. Examples of the phosphate compound represented by the general formula (I) include the following general formulas (V) to (I)
X) and the like. Among them, a compound represented by the general formula (V
Compounds represented by I) are preferred.

[0020]

Embedded image

Embedded image

(E) The amount of the plasticizer is 260
There is no particular limitation as long as the effect of lowering the flexural modulus at ℃ can be obtained.
Is preferable, and 5 to 15% by weight is more preferable. 2% by weight
If it is less than 10%, the effect of reducing the bending elastic modulus of the molded article tends to be insufficient, and if it exceeds 18% by weight, the reflow crack resistance and the moisture resistance reliability tend to decrease.

The epoxy molding material for sealing of the present invention preferably further contains (F) a low-stressing agent from the viewpoint of thermal shock resistance, and (F) the effect of the low-stressing agent is as follows. There is no particular limitation as long as it can be obtained. For example, thermoplastic elastomers such as styrene, olefin, urethane, polyester, polyether, polyamide, and polybutadiene, NR (natural rubber), NBR (acrylonitrile-butadiene rubber) ), Rubber particles such as acrylic rubber, urethane rubber and silicone powder, methyl methacrylate-styrene-butadiene copolymer (MBS),
Rubber particles having a core-shell structure such as methyl methacrylate-silicone copolymer, methyl methacrylate-butyl acrylate copolymer, and the like, may be used alone or in combination of two or more. . Among them, from the viewpoint of thermal shock resistance, diglycidyl ether of bisphenol A propylene oxide adduct (trade name: Glycier BPP-350, manufactured by Sanyo Chemical Industry Co., Ltd.), polybutylene terephthalate-polytetramethylene glycol copolymer (Toyobo Co., Ltd.) Product name Perprene P-40
B, P-30B) and the like, and a methyl methacrylate-styrene-butadiene copolymer (MB
Rubber particles such as S) are preferred, rubber particles having a core-shell structure are more preferred, and methyl methacrylate-styrene-butadiene copolymer (MBS) is even more preferred.

(F) When rubber particles are used as the stress reducing agent, the particle size is not particularly limited, but the dispersibility in the sealing epoxy resin molding material and the fluidity of the sealing epoxy resin molding material are not limited. From the viewpoint of the maximum particle diameter of the secondary particles is 20
It is preferably 0 μm or less, more preferably 150 μm or less, even more preferably 100 μm or less. When the maximum particle diameter of the secondary particles is larger than 200 μm, the fluidity of the epoxy resin molding compound for sealing decreases, and the dispersion of the low stress agent in the epoxy resin molding compound for sealing becomes uneven. And the effect of addition tends to be insufficient.

The amount of the (F) low-stressing agent is not particularly limited as long as the effect of improving the thermal shock resistance is obtained, but is preferably 5 to 25% by weight, more preferably 6 to 20% by weight of the epoxy resin (A).
% Is more preferred. If it is less than 5% by weight, the effect of improving thermal shock resistance tends to be insufficient, and if it exceeds 25% by weight, the fluidity tends to decrease.

The epoxy resin molding material for sealing of the present invention may optionally contain a flame retardant for imparting flame retardancy. The flame retardant is not particularly limited, and a conventionally known flame retardant can be used. Brominated epoxy resin, antimony trioxide, phosphate, red phosphorus, melamine, melamine derivative, compound having a triazine ring, cyanuric acid derivative , Nitrogen-containing compounds such as isocyanuric acid derivatives, phosphorus / nitrogen-containing compounds such as cyclophosphazene, and metal compounds such as zinc oxide, iron oxide, molybdenum oxide, and ferrocene, and the like. They may be used in combination. The amount of the flame retardant is not particularly limited as long as the flame retardant effect is achieved.
1 to 30% by weight based on the epoxy resin is preferable,
15% by weight is more preferred.

The sealing epoxy resin molding material of the present invention may optionally contain an anion exchanger for the purpose of improving the moisture resistance and high-temperature storage characteristics of the IC. The anion exchanger is not particularly limited, and conventionally known ones can be used. Examples thereof include hydrotalcites, and hydrated oxides of elements selected from magnesium, aluminum, titanium, zirconium, and bismuth. These may be used alone or in combination of two or more. Among them, hydrotalcite represented by the following formula (X) is preferable.

Embedded image Mg _1-X Al _X (OH) ₂ (CO ₃ ) _{X / 2} · mH ₂ O (X) (0 <X ≦ 0.5, m is a positive integer) The blending amount of the body is not particularly limited as long as it is a sufficient amount capable of capturing anions such as halogen ions, but 0.1 to 30% by weight based on the epoxy resin (A).
Is more preferable, and 1 to 5% by weight is more preferable.

The epoxy resin molding material for encapsulation of the present invention includes epoxy silane, mercapto silane, amino silane, alkyl silane, ureido silane, and the like as coupling agents for improving the adhesion between the resin component and the inorganic filler.
Known additives such as silane-based compounds such as vinylsilane, titanium-based compounds, aluminum chelates, and aluminum / zirconium-based compounds can be added as necessary. These may be used alone or in combination of two or more. In addition to the coupling agent, an adhesion promoter may be added as needed to improve the adhesiveness. In particular, the addition of an adhesion promoter is effective for improving the adhesiveness between the copper frame and the sealing epoxy resin molding material. There is no particular limitation on the adhesion promoter,
Conventionally known ones can be used, for example, imidazole, triazole, tetrazole, triazine and the like and derivatives thereof, anthranilic acid, gallic acid, malonic acid, malic acid, maleic acid, aminophenol, quinoline and the like and derivatives thereof And an aliphatic acid amide compound, a dithiocarbamate, and a thiadiazole derivative. These may be used alone or in combination of two or more. Other additives include higher fatty acids, higher fatty acid metal salts, ester waxes, polyolefin waxes, release agents such as polyethylene and polyethylene oxide, silicone oils, stress relaxation agents such as silicone rubber powder, carbon black, Colorants such as organic dyes, organic pigments, titanium oxide, lead red,
If necessary, it can be blended with the sealing epoxy resin molding material of the present invention.

The sealing epoxy resin molding material of the present invention comprises:
As long as the various raw materials can be uniformly dispersed and mixed, it can be prepared by any method, but as a general method,
A method in which raw materials having a predetermined compounding amount are sufficiently mixed by a mixer or the like, melt-kneaded by a mixing roll, an extruder, or the like, and then cooled and pulverized can be used. It is easy to use if it is tableted with dimensions and weight that match the molding conditions.

The epoxy resin molding material for sealing of the present invention is
After molding, it can be post-cured as required to produce a molded article. The flexural modulus at 260 ° C. of the molded product of the epoxy resin molding material for sealing of the present invention must be 550 MPa or less from the viewpoint of reflow crack resistance, preferably 500 MPa or less, more preferably 480 MPa or less. Here, the flexural modulus at 260 ° C. of the molded article is defined as a molded article produced by molding an epoxy resin molding material for sealing and performing post-curing as necessary.
It is a value obtained by testing according to K-6911. In the present invention, (A) epoxy resin, (B)
Curing agent, (C) curing accelerator, (D) inorganic filler, (E)
By adjusting the combination of the plasticizer and other components and the amounts of these components, it is possible to obtain a sealing epoxy resin molding material in which the flexural modulus at 260 ° C. of the molded product is 550 MPa or less. It is particularly important to select an epoxy resin used as the component (A), a curing agent used as the component (B), and a plasticizer used as the component (E).

As an electronic component device having an element sealed with the epoxy resin molding material for sealing obtained in the present invention, a lead frame, a wired tape carrier, a wiring board, glass, a support member such as a silicon wafer or the like can be used. , Active elements such as semiconductor chips, transistors, diodes, thyristors, etc., and passive elements such as capacitors, resistors, resistor arrays, coils, polyswitches, etc. are mounted, and necessary parts are molded with the epoxy resin for sealing of the present invention. An electronic component device sealed with a material is exemplified. Such electronic component devices include, for example, 42 alloy, copper lead frame, Ni
A semiconductor element was fixed on a lead frame such as a copper lead frame (PPF) that had been subjected to a three-layer plating process of -Pd-Au, and a terminal portion of the element such as a bonding pad and a lead portion were connected by wire bonding or a bump. DIP (Dual Inline Packag) formed by encapsulation using the epoxy resin molding material for encapsulation of the present invention by a transfer molding method or the like.
e), PLCC (Plastic Leaded Chip Carrier), QF
P (Quad Flat Package), SOP (Small Outline Pac)
kage), SOJ (Small Outline J-lead package), T
SOP (Thin Small Outline Package), TQFP (Th
In general, a resin-encapsulated IC package such as a Quad Flat Package, a TCP (Tape Carrier Package) in which a semiconductor chip connected to a tape carrier by a bump is sealed with the epoxy resin molding material of the present invention, and wiring A semiconductor chip connected to wiring formed on a plate or glass by wire bonding, flip chip bonding, soldering, etc.
Active elements such as transistors, diodes, thyristors and / or passive elements such as capacitors, resistors, coils, etc.
COB sealed with the epoxy resin molding material for sealing of the present invention
(Chip On Board) Modules, hybrid ICs, multi-chip modules, elements mounted on the surface of an organic substrate with terminals for wiring board connection formed on the back surface, and the wiring formed on the elements and the organic substrate by bump or wire bonding After connection, BGA (Ball Grid Array), CSP in which the element is sealed with the epoxy resin molding material for sealing of the present invention.
(Chip Size Package). The epoxy resin molding material for sealing of the present invention can be effectively used for a printed circuit board, and excellent reliability is obtained for a hybrid IC obtained by mounting various elements and electronic components on a ceramic substrate and then sealing the whole. Can be obtained. Especially when applied to an electronic component device mounted on a wiring board by a surface mounting method, the epoxy resin molding material for sealing of the present invention can exhibit excellent reliability, and an electronic device using lead-free solder requiring high temperature reflow. It is also suitably used for component devices.

A method for sealing an electronic component device using the epoxy resin molding material for sealing obtained in the present invention includes the following.
The low pressure transfer molding method is the most common, but an injection molding method, a compression molding method, or the like may be used.

[0032]

Next, the present invention will be described with reference to examples, but the scope of the present invention is not limited to these examples.

Examples 1 to 15 and Comparative Examples 1 to 2 Epoxy equivalents 195, softening point 62
° C ortho-cresol novolak epoxy resin (Epoxy resin 1: trade name ESCN- manufactured by Sumitomo Chemical Co., Ltd.)
190), a stilbene type epoxy resin having an epoxy equivalent of 210 and a melting point of 120 ° C. (Epoxy resin 2: ESLV-210, trade name, manufactured by Sumitomo Chemical Co., Ltd.), a phenol aralkyl resin having a hydroxyl equivalent of 174 as a curing agent and a softening point of 68 ° C. Product name: MILEX XL-22 manufactured by Mitsui Chemicals, Inc.
5), triphenylphosphine and p-
Adduct with benzoquinone, average particle size 1 as inorganic filler
7.5 μm, spherical fused silica having a specific surface area of 3.8 m ² / g, a phosphate compound represented by the following general formula (VI) (plasticizer 1) or an epoxidized soybean oil (plasticizer 2: Asahi Denka) Adekaiser O-1 (trade name, manufactured by Kogyo Co., Ltd.)
30P), a methyl methacrylate-styrene-butadiene copolymer (trade name: Metablen C-223, manufactured by Mitsubishi Rayon Co., Ltd.) as a stress reducing agent, an epoxy equivalent of 375 as a flame retardant, a softening point of 80 ° C., and a bromine content of 48% by weight. Bisphenol A type brominated epoxy resin (Epoxy resin 3), antimony trioxide, γ-glycidoxypropyltrimethoxysilane as a coupling agent, and carnauba wax as other additives (Ceralica NODA Co., Ltd.)
Carbon black (trade name M, manufactured by Mitsubishi Chemical Corporation)
A-100) was blended in parts by weight shown in Tables 1 and 2, respectively, and kneaded in a roll at a kneading temperature of 80 ° C. and a kneading time of 10 minutes, and sealing of Examples 1 to 15 and Comparative Examples 1 and 2. Epoxy resin molding material was prepared.

[0034]

Embedded image

[0035]

[Table 1]

[0036]

[Table 2]

The encapsulating epoxy resin molding materials of Examples and Comparative Examples were evaluated by the following tests. The evaluation results are shown in Tables 3 and 4. The molding of the sealing epoxy resin molding material is performed by using a transfer molding machine at a mold temperature of 1.
The test was performed under the conditions of 80 ° C., a molding pressure of 6.9 MPa, and a curing time of 90 seconds. Post-curing was performed at 180 ° C. for 5 hours. (1) Spiral flow (indicator of fluidity) Using a mold for spiral flow measurement according to EMMI-1-66, an epoxy resin molding material for sealing is molded under the above conditions, and a flow distance (cm) is obtained. Was. (2) Hardness when hot The epoxy resin molding material for sealing is 50 mm in diameter under the above conditions.
X Formed into a disk having a thickness of 3 mm and measured immediately after molding using a Shore D hardness meter. (3) Flexural modulus The epoxy resin molding material for sealing is 70 mm × 1 under the above conditions.
After molding into a test piece of 0 mm x 3 mm and post-curing, A & D
Using Tensilon manufactured by KK, a three-point support type bending test in accordance with JIS-K-6911 was performed at 260 ° C. and a head speed of 1.5 mm / min to determine a bending elastic modulus. (4) Reflow crack resistance An 80-pin flat package with an outer dimension of 20 × 14 × 2 mm in which an 8 × 10 mm silicone chip is mounted on a copper lead frame (PPF) that has been subjected to a Ni—Pd—Au three-layer plating process. , Molded and post-cured under the above conditions using an epoxy resin molding material for encapsulation, at 85 ° C., 60%
After humidification under the condition of RH, the reflow process is performed three times at predetermined intervals by using an IR reflow device (TRS35-20NS manufactured by Tamura Corporation) under the condition that the temperature of the upper and lower surfaces of the package is 260 ° C. for 10 seconds. Then, the presence or absence of cracks was observed, and the number of crack occurrence packages with respect to the number of test packages (5) was evaluated. (5) Moisture resistance reliability 6 × 6 with aluminum wiring of line width 10 μm and thickness 1 μm
An 80-pin flat package having an outer dimension of 19 × 14 × 2.7 mm and a test silicone chip of × 0.4 mm is molded under the above conditions using an epoxy resin molding material for encapsulation, and is post-cured to produce a flat package. After performing the pre-treatment, it was humidified, and a disconnection defect due to corrosion of the aluminum wiring was examined at predetermined time intervals, and evaluated by the number of defective packages with respect to the number of test packages (7). The pretreatment was performed at 85 ° C., 85% RH, and 72%.
After humidification under the condition of time, a vapor phase reflow treatment was performed at 215 ° C. for 90 seconds. Subsequent humidification is 0.2M
The test was performed under the conditions of Pa and 121 ° C. (6) Thermal shock resistance A thermal shock test device (THERMAL SHOC manufactured by Tabai Espec Corp.)
K CHAMBER TSA-70H)
Apply a thermal shock at 0 ° C./15 minutes and at −65 ° C./15 minutes,
The occurrence of cracks after a predetermined cycle was observed and evaluated by the number of crack occurrence packages with respect to the number of test packages (10). (7) Appearance of molded product Using a disk immediately after molding prepared in the same manner as in (2) above,
The appearance of the molded article was evaluated by observing the exudation. First, the molded product was visually observed, and 成形 indicates that the liquid component was not observed on the surface of the molded product, and △ indicates that the liquid component was slightly observed. Next, a molded product in which no liquid component was observed on the surface was visually observed, and a sample in which the liquid did not adhere when the surface was traced with a finger was evaluated as ◎.

[0038]

[Table 3]

[0039]

[Table 4]

In the present invention, Comparative Example 1 containing no (E) plasticizer and 26 even if containing (E) a plasticizer were used.
Comparative Example 2 in which the flexural modulus at 0 ° C. does not satisfy the specified range of the present invention is inferior in reflow crack resistance. On the other hand, Examples 1 to 15 all have good fluidity, hot hardness, and reflow crack resistance. In particular, Examples 2 to 4, 6 to 10, 12, 13 and 15 using (E) a plasticizer in a suitable amount are extremely excellent in reflow crack resistance and humidity resistance, and among them, (F) Examples 7 to 10 in which a low-stressing agent was used in a suitable amount.
9 and 15 are also remarkably excellent in thermal shock resistance. Example 1 further containing epoxidized soybean oil as a plasticizer
In Nos. 1 to 15, the appearance of the molded product is all good.

[0041]

The sealing epoxy resin molding material according to the present invention has good moldability such as fluidity and curability.
-When applied to an electronic component device using a copper lead frame (PPF) that has been subjected to a three-layer plating treatment of Pd-Au, excellent reflow resistance even under severe reflow temperature conditions of 260 ° C. as shown in the examples. Shows cracking properties,
Even if lead-free solder is used, a highly reliable electronic component device can be obtained, so that its industrial value is great.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court II (Reference) H01L 23/31 (72) Inventor Takatoshi Ikeuchi 48 Wadai, Tsukuba, Ibaraki Pref. Hitachi Chemical Co., Ltd. 72) Inventor Megumi Matsui 48 Wadai, Tsukuba-shi, Ibaraki F-term in Hitachi Chemical Co., Ltd. F-term (reference) 4J002 AC014 AC074 BB004 BB154 BC044 BG044 BL014 CC03X CC04X CC05X CD04W CD05W CD054 CD06W CD13W CD163 CD17W CD20W CF03004 CF104 CL074 CL084 CP034 DE077 DE097 DE137 DE147 DE187 DE237 DF017 DJ007 DJ017 DK007 DL007 EH148 EN026 EN046 EU116 EU136 EW016 EW048 EY016 FA087 FD017 FD028 FD137 FD153 FD156 FD204 GQ00 GQ01 4J036 AA01 DC01 AF08 DC08 AF01 DC08 AF01 DC FA03 FA05 FA10 FA11 FA12 FB07 JA07 4M109 AA01 EA02 EB02 EB04 EB12 EB18 EB19 EC03 EC05

Claims (12)

[Claims] (1) an epoxy resin, (B) a curing agent,
An epoxy resin molding material for sealing which contains (C) a curing accelerator, (D) an inorganic filler and (E) a plasticizer as essential components, and has a flexural modulus at 260 ° C. of 550 MPa or less. 2. The epoxy resin molding material for sealing according to claim 1, further comprising (F) a stress reducing agent. 3. The molding epoxy resin molding material according to claim 1, wherein the amount of the plasticizer (E) is 2 to 18% by weight based on the epoxy resin (A). 4. The molding epoxy resin molding material according to claim 1, wherein (E) the plasticizer contains an epoxy plasticizer and / or a phosphate plasticizer. 5. The epoxy resin molding material for sealing according to claim 4, wherein the epoxy plasticizer is epoxidized soybean oil. 6. The epoxy resin molding material for sealing according to claim 4, wherein the phosphate plasticizer is a phosphate compound. 7. A phosphoric acid ester compound represented by the following general formula (I):
The epoxy resin molding material for sealing according to claim 6, which is a compound represented by the formula: Embedded image (Here, R represents an alkyl group having 1 to 4 carbon atoms, all of which may be the same or different. Ar represents a divalent organic group having a substituted or unsubstituted aromatic ring, and m represents 0 Represents an integer of 2 to 2) 8. The epoxy resin molding material for sealing according to claim 2, wherein (F) the stress reducing agent is rubber particles. 9. The method according to claim 1, wherein the epoxy resin (A) contains an epoxy resin represented by the following general formula (II) and an epoxy resin represented by the following general formula (III). Epoxy molding compound for sealing. Embedded image (Where R represents a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 5 carbon atoms, and n represents an integer of 0 to 10). (Here, R ^{1 to} R ⁴ are selected from a hydrogen atom and a substituted or unsubstituted monovalent hydrocarbon group having 1 to 5 carbon atoms, all of which may be the same or different. Indicates an integer.) 10. The sealing epoxy according to claim 9, wherein the weight ratio of the epoxy resin represented by the general formula (II) to the epoxy resin represented by the general formula (III) is 2: 8 to 8: 2. Resin molding material. 11. The epoxy resin molding material for sealing according to claim 1, wherein (B) the curing agent contains a phenol resin represented by the following general formula (IV). Embedded image (Here, R represents a hydrogen atom or a substituted or unsubstituted monovalent hydrocarbon group having 1 to 10 carbon atoms, and n represents an integer of 0 to 8.) 12. An electronic component device comprising an element sealed with the sealing epoxy resin molding material according to claim 1.