JP2011079904A - Epoxy resin composition, resin composition for seal-filling semiconductor, and semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an epoxy resin composition and a resin composition for seal-filling semiconductor excellent in toughness and heat resistance, and a semiconductor device manufactured using the same. <P>SOLUTION: The epoxy resin composition includes (a) an epoxy resin, (b) a curing agent, (c) a flexible epoxy resin, and (d) a compound having an acryl group or a methacryl group. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an epoxy resin composition, a semiconductor sealing resin composition, and a semiconductor device.

  In a semiconductor device in which a semiconductor chip and a substrate are flip-chip connected, there is a gap between the semiconductor chip and the substrate in order to disperse the thermal stress resulting from the difference in thermal expansion coefficient between the semiconductor chip and the substrate and increase the connection reliability. It is sealed with resin. As a sealing method, a method of injecting a liquid sealing filling resin composition using a capillary phenomenon after connecting a semiconductor chip and a substrate is widely adopted.

  In recent years, semiconductor chips tend to increase in size as the functionality of semiconductor devices increases. For this reason, since the generated thermal stress increases, the thermal stress exceeding the strength of the sealing resin acts to generate cracks, and the reliability may decrease. There is a strong demand for the system.

  As a resin composition for sealing filling, a liquid epoxy resin composition containing a liquid epoxy, a liquid curing agent and an inorganic filler as main components is known. For example, Patent Documents 1 and 2 below propose techniques for toughening the liquid epoxy resin composition as described above.

JP 2003-183351 A JP 2004-99810 A

  However, as described in Patent Documents 1 and 2, in the method of toughening with a modifier such as a solid epoxy resin or polymer, the viscosity of the resin composition tends to increase. Is limited, and it is difficult to obtain a sufficient toughening effect. The increase in the viscosity of the resin composition leads to a decrease in workability because the time for sealing and filling the gap between the semiconductor chip and the substrate becomes longer. In addition, when rubber fine particles are blended, the toughening effect may not be exhibited unless the adhesion between the fine particles and the epoxy resin is sufficiently high. On the other hand, it is conceivable that the cured product is toughened by reducing the crosslink density to improve the plastic deformability, but this method may reduce the heat resistance of the cured product.

  This invention is made | formed in view of the said situation, and provides the epoxy resin composition excellent in toughness and heat resistance, the resin composition for semiconductor sealing filling, and the semiconductor device manufactured using it. With the goal.

  In order to solve the above-mentioned problems, the present inventors have intensively studied the toughening of the epoxy resin composition, and as a result, the epoxy resin composition has a specific structure and an epoxy resin having a specific group as a modifier. As a result, it was found that the obtained cured product increased in fracture energy and fracture strain (toughened) and exhibited a high fracture toughness value, and further improved in heat resistance, and completed the present invention. .

  That is, the epoxy resin composition of the present invention comprises (a) an epoxy resin, (b) a curing agent, (c) a flexible epoxy resin, and (d) a compound having an acryl group or a methacryl group. To do.

  According to the epoxy resin composition of the present invention, a cured product having excellent toughness and heat resistance can be formed by having the above configuration. The mechanism by which toughening is manifested and the mechanism by which heat resistance is improved in the epoxy resin composition of the present invention have not been clarified, but excellent toughness and heat resistance can be obtained by adding the above component (c). A structure in which the epoxy cured product network having improved and the cured product network formed by the acrylic group or methacrylic group of the component (d) are intertwined with each other, that is, an interpenetrating network (IPN) is constructed. The present inventors believe that this is caused by this.

  From the viewpoint of obtaining a high level of toughness and heat resistance, the compound (d) is preferably a compound having an acrylic group or a methacryl group and an epoxy resin. In this case, in addition to the construction of the above IPN, the IPN structure is reinforced by cross-linking each other's networks via the epoxy groups of the above compounds, achieving a high level of toughness and heat resistance. The present inventors speculate that this has been done.

  From the viewpoint of heat resistance, storage stability, and low outgassing properties, the (b) curing agent is preferably an aromatic amine compound having a primary or secondary amino group.

  The epoxy resin composition of the present invention can further contain an inorganic filler.

  The epoxy resin composition of the present invention is preferably liquid at 25 ° C. Here, “liquid” means that fluidity is exhibited at 25 ° C. From the viewpoint of workability, the viscosity is preferably 1000 Pa · s or less.

  This invention also provides the resin composition for semiconductor sealing filling which consists of an epoxy resin composition of this invention. According to the resin composition for semiconductor sealing filling of the present invention, a sealing resin excellent in toughness can be formed by filling the space between the semiconductor chips or between the semiconductor chip and the substrate.

  The present invention also provides a semiconductor device manufactured by sealing a semiconductor element using the resin composition for semiconductor sealing filling of the present invention.

  The present invention also includes a circuit board, a semiconductor element electrically connected to the circuit board, and a cured product of the resin composition for semiconductor sealing filling of the present invention, between the circuit board and the semiconductor element. A semiconductor device is provided that includes a sealing resin that seals the gap. The semiconductor device of the present invention is a case where a semiconductor element having a large size is provided by the gap between the circuit board and the semiconductor element being sealed by the resin composition for semiconductor sealing filling of the present invention. However, cracks are less likely to occur and can be excellent in reliability.

  ADVANTAGE OF THE INVENTION According to this invention, the epoxy resin composition excellent in toughness and heat resistance, the resin composition for semiconductor sealing filling, and the semiconductor device manufactured using it can be provided.

It is a schematic cross section showing one embodiment of a semiconductor device of the present invention.

  The epoxy resin composition of the present invention comprises (a) an epoxy resin, (b) a curing agent, (c) a flexible epoxy resin, and (d) a compound having an acrylic group or a methacryl group.

  (A) The epoxy resin is not particularly limited as long as it is bifunctional or higher. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin , Biphenyl type epoxy resin, hydroquinone type epoxy resin, diphenyl sulfide skeleton containing epoxy resin, phenol aralkyl type polyfunctional epoxy resin, naphthalene skeleton containing polyfunctional epoxy resin, dicyclopentadiene skeleton containing polyfunctional epoxy resin, triphenylmethane skeleton containing poly A functional epoxy resin, an aminophenol type epoxy resin, a diaminodiphenylmethane type epoxy resin, and other various polyfunctional epoxy resins can be used. Among these, from the viewpoint of low viscosity, low water absorption, and high heat resistance, bisphenol A type epoxy resin, bisphenol F type epoxy resin, naphthalene skeleton-containing polyfunctional epoxy resin, dicyclopentadiene skeleton-containing polyfunctional epoxy resin, tri It is desirable to use a phenylmethane skeleton-containing polyfunctional epoxy resin, an aminophenol type epoxy resin, or the like. These epoxy resins can be used individually by 1 type or in mixture of 2 or more types.

  The epoxy resin can be used in liquid or solid form, but is preferably liquid at 25 ° C. from the viewpoints of low viscosity and moldability and workability.

  The content of the (a) epoxy resin in the epoxy resin composition of the present invention is preferably 10 to 99% by mass and more preferably 15 to 90% by mass based on the total amount of the composition.

  (B) The curing agent may be any one that functions as a curing agent for epoxy resins. For example, imidazoles, acid anhydrides, amines, phenols, hydrazides, polymercaptans, Lewis acid-amine complexes Etc. can be used. Among them, it is desirable to use imidazoles, acid anhydrides, amines and phenols from the viewpoints of low viscosity, storage stability, heat resistance of the cured product, etc., and imidazoles and amines from the viewpoint of moisture resistance reliability. More preferably, phenols are used.

  The curing agent can be used in liquid or solid form, but is preferably liquid at 25 ° C. from the viewpoint of lowering viscosity, workability during blending and processing.

  Examples of imidazoles include 2MZ, C11Z, 2PZ, 2E4MZ, 2P4MZ, 1B2MZ, 1B2PZ, 2MZ-CN, 2E4MZ-CN, 2PZ-CN, C11Z-CN, 2PZ-CNS, C11Z-CNS, 2MZ-A, and C11Z. Examples thereof include -A, 2E4MZ-A, 2P4MHZ, 2PHZ, 2MA-OK, 2PZ-OK (manufactured by Shikoku Kasei Kogyo Co., Ltd., product name), and compounds obtained by adding these imidazoles to an epoxy resin. In addition, those encapsulating these curing agents with a polyurethane-based or polyester-based polymer substance and making them into microcapsules are preferable because the pot life is extended. These may be used alone or in admixture of two or more.

  When blending imidazoles as a curing agent, the blending amount is desirably 0.1 to 10% by mass, more preferably 0.5 to 10% by mass, and further preferably 1 to 10% with respect to the epoxy resin. % By mass. If the blending amount is less than 0.1% by mass, the composition may not be cured sufficiently, and if it exceeds 10% by mass, the storage stability may be deteriorated.

  Examples of acid anhydrides include methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, methylheimic anhydride, pyromellitic dianhydride, benzophenonetetracarboxylic acid Anhydride, 3,4-dimethyl-6- (2-methyl-1-propenyl) -1,2,3,6-tetrahydrophthalic anhydride, 1-isopropyl-4-methyl-bicyclo [2.2.2 And oct-5-ene-2,3-dicarboxylic acid anhydride. These may be used alone or in admixture of two or more.

  When blending acid anhydrides as curing agents, the blending amount is the ratio of the number of epoxy groups in the epoxy resin to the number of carboxylic acids generated from the acid anhydride groups (number of epoxy groups / number of carboxylic acids). Is preferably set to 0.5 to 1.5, more preferably 0.7 to 1.2. If the ratio (number of epoxy groups / number of carboxylic acids) is less than 0.5, carboxylic acid groups may remain excessively and the moisture resistance reliability may be reduced. May not progress.

  As the amines, compounds having at least one primary or secondary amino group in the molecule can be used, and aromatic amines from the viewpoint of low outgassing property, storage stability and heat resistance of the cured product. Is desirable. Examples of aromatic amines include diaminodiphenylmethane, diaminodiphenylsulfone, diaminodiphenyl sulfide, metaxylenediamine, 3,3′-diethyl-4,4′-diaminodiphenylmethane, 3,3 ′, 5,5′-tetraethyl. -4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfide, 2,2-bis- [4- (4-aminophenoxy) phenyl] -hexafluoropropane, 2 , 2-bis (4-aminophenyl) -hexafluoropropane, 2,4-diaminotoluene, 1,4-diaminobenzene, 1,3-diaminobenzene, diethyltoluenediamine, dimethyltoluenediamine, anilines, alkylated anilines , N-alkylated anilines, Etc. These may be used alone or in admixture of two or more.

  When amines are blended as a curing agent, the blending amount is such that the ratio of the number of epoxy groups to the number of active hydrogens in the epoxy resin (number of epoxy groups / number of active hydrogens) is 0.5 to 1.5. It is desirable to set so as to be, more preferably 0.7 to 1.2. If the ratio (number of epoxy groups / number of active hydrogens) is less than 0.5, amines may remain excessively and the moisture resistance reliability may decrease. May not progress.

  Examples of phenols include bisphenol resin, phenol novolak resin, naphthol novolak resin, allylated phenol novolak resin, biphenol resin, cresol novolak resin, phenol aralkyl resin, cresol naphthol formaldehyde polycondensate, triphenylmethane type polyfunctional phenol resin. And xylylene-modified phenol novolak resin, xylylene-modified naphthol novolak resin, various polyfunctional phenol resins, and the like. These may be used alone or in admixture of two or more.

  When blending phenols as a curing agent, the blending amount is such that the ratio of the number of epoxy groups of epoxy resin to the number of phenolic hydroxyl groups (number of epoxy groups / number of phenolic hydroxyl groups) is 0.5 to 1. It is desirable to set it to 5, more preferably 0.7 to 1.2. If the above ratio (number of epoxy groups / number of phenolic hydroxyl groups) is less than 0.5, phenols may remain excessively and the moisture resistance reliability may be reduced. May not progress.

  When acid anhydrides, amines, and phenols are used as the curing agent, a curing accelerator can be used in combination. As a hardening accelerator, the said imidazole is mentioned, for example. The blending amount of the curing accelerator is appropriately set in consideration of the time required for curing and storage stability.

  (C) As a flexible epoxy resin, the epoxy resin in which the epoxy group in a molecule | numerator does not comprise the glycidyl ether structure with a phenolic hydroxyl group is mentioned, for example. More specifically, an epoxy resin in which the epoxy group in the molecule forms a glycidyl ether structure with an alcoholic hydroxyl group, an epoxy resin in which the epoxy group in the molecule forms a glycidyl ester structure with a carboxyl group, Examples thereof include an epoxy resin in which an epoxy group has a glycidylamine structure, and an alicyclic epoxy resin.

  From the viewpoint of reactivity and toughening effect, the flexible epoxy resin is preferably an epoxy resin in which an epoxy group in the molecule forms a glycidyl ether structure with an alcoholic hydroxyl group. As this epoxy resin, for example, an epoxy resin synthesized by an addition reaction between alcohols and epichlorohydrin or an acetalization reaction between vinyl ethers and glycidol can be used.

  Examples of the flexible epoxy resin include liquid epoxy resin ZX-1627 (product name, ethylene oxide-modified bisphenol A type epoxy, epoxy equivalent 237) manufactured by Toto Kasei Co., Ltd., and liquid epoxy resin YL7175-500 manufactured by Japan Epoxy Resin Co., Ltd. Product name, epoxy equivalent 487), YL7175-1000 (product name, epoxy equivalent 1124), liquid epoxy resin BEO-60E (product name, bisphenol A bis (triethylene glycol glycidyl ether) ether, epoxy, manufactured by Shin Nippon Chemical Co., Ltd. Equivalent 360), BPO-20E (Product name, Bisphenol A bis (propylene glycol glycidyl ether) ether, Epoxy equivalent 320), Epoxy resin Ogsol EG (Product name, Ethylene, manufactured by Osaka Gas Chemical Co., Ltd.) Oxol-modified 4,4 ′-(9-fluorenylidene) bisphenol type epoxy, epoxy equivalent 294), Ogsol EG-210 (product name, ethylene oxide modified 4,4 ′-(9-fluorenylidene) bisphenol type epoxy, epoxy equivalent 342), etc. Can be used.

  The flexible epoxy resin desirably contains at least two epoxy groups in the molecule from the viewpoint of being incorporated into the cured product network skeleton and sufficiently exhibiting the toughening effect.

［式（１）中、Ｘは２価の有機基を示し、Ｌ^１及びＬ^２はそれぞれ独立に、芳香族基以外の基を示す。］ Moreover, what has a structure shown by following General formula (1) can be used for a flexible epoxy resin.

[In Formula (1), X represents a divalent organic group, and L ¹ and L ² each independently represent a group other than an aromatic group. ]

In the present invention, L ¹ and L ² in the general formula (1) are ethyleneoxyethyl group, di (ethyleneoxy) ethyl group, tri (ethyleneoxy) ethyl group, propyleneoxypropyl group, di (propyleneoxy). It is preferably a polyether group such as a propyl group or a tri (propyleneoxy) propyl group, or an alkyl group having 2 to 15 carbon atoms.

  In addition, as a flexible epoxy resin, from the viewpoint of reducing the crosslink density of the cured product and improving the plastic deformability, it is flexible by polyethylene oxide modification, polysiloxane modification, polyether modification, caprolactone modification, linear alkyl modification, etc. An epoxy resin into which a skeleton is introduced may be used.

  Furthermore, the flexible epoxy resin desirably has a bisphenol skeleton in the molecule from the viewpoint of heat resistance. Examples of the bisphenol skeleton include bisphenol A type, bisphenol F type, bisphenol AD type, bisphenol S type, 4,4 '-(9-fluorenylidene) bisphenol type, and the like. As such an epoxy resin, for example, X in the general formula (1) is a bisphenol A skeleton, a bisphenol F skeleton, a bisphenol AD skeleton, a bisphenol S skeleton, or a 4,4 ′-(9-fluorenylidene) bisphenol skeleton. And the phenolic hydroxyl groups in these skeletons are ethyleneoxyethyl, di (ethyleneoxy) ethyl, tri (ethyleneoxy) ethyl, propyleneoxypropyl, di (propyleneoxy) propyl, tri (propylene) Examples thereof include an oxy) propyl group, an alkyl group having 2 to 15 carbon atoms, and a polysiloxane group, which contain a plurality of bisphenol skeletons.

  The flexible epoxy resin preferably has an epoxy equivalent of 200 or more from the viewpoint of toughening the cured product. If the epoxy equivalent of the flexible epoxy resin is less than 200, the effect of reducing the crosslink density of the cured product and improving the plastic deformability is not sufficiently exhibited, and it becomes difficult to obtain a toughening effect.

  A flexible epoxy resin can be mix | blended individually by 1 type or in combination of 2 or more types.

  The flexible epoxy resin can be used in a liquid state or in a solid state, but is preferably in a liquid state at 25 ° C. from the viewpoint of viscosity reduction, workability during blending and processing.

  (C) As a compounding quantity of a flexible epoxy resin, it is desirable to set it as 0.5-20 mass parts with respect to 100 mass parts of total amounts of (a) epoxy resin and (b) hardening | curing agent, and 1-15 masses. More preferably, the content is 5 to 15 parts by mass. If the blending amount is less than 0.5 parts by mass, the effect of toughening may not be sufficiently exhibited, and if it exceeds 20 parts by mass, the viscosity may increase and workability may decrease or heat resistance may decrease. There is.

  (D) The compound having an acryl group or a methacryl group may be any compound having at least one acryl group or methacryl group in the molecule. Examples of the compound having an acryl group include dicyclopentenyl acrylate and dicyclo Pentenyloxyethyl acrylate, dicyclopentanyl acrylate, benzyl acrylate, nonylphenoxy polyethylene glycol acrylate, nonanediol diacrylate, polypropylene glycol diacrylate, EO-modified bisphenol A diacrylate, tris (2-acryloyloxyethyl) isocyanurate, bis ( 2-acryloyloxyethyl) hydroxyethyl isocyanurate, trimethylolpropane triacrylate, pentaerythritol tris Chryrate, pentaerythritol tetraacrylate, ditrimethylolpropane tetraacrylate, dipentaerythritol hexaacrylate, dipentaerythritol pentaacrylate, ditrimethylolpropane tetraacrylate, 2-hydroxy-3-phenoxypropyl acrylate, tricyclodecane dimethanol diacrylate, bis Examples thereof include phenoxyethanol full orange acrylate, and examples of the compound having a methacryl group include a methacrylate derivative of the above compound having an acryl group. Further, (d) the compound having an acryl group or a methacryl group may be not only a compound having a linear structure but also a terminal acrylate-modified dendrimer having a highly branched structure. As such a compound, V # 1000, V # 1020, V # 1080 and the like manufactured by Osaka Organic Chemical Industry Co., Ltd. are available.

  Further, from the viewpoint of obtaining a high level of toughness and heat resistance, the compound (d) is preferably a compound having an acryl group or a methacryl group and an epoxy resin. Such compounds include, for example, polyfunctional epoxy resins having at least two epoxy groups in the molecule, acrylic acid and / or methacrylic acid, epoxy groups and carboxyls in the presence of triphenylphosphine and tetrabutylammonium bromide. Mix so that the equivalent ratio of groups is 0.1 to 0.9 (equivalent ratio = number of carboxyl groups in acrylic acid and / or methacrylic acid / number of epoxy groups in epoxy resin). It can be synthesized by reacting parts with acrylic acid and / or methacrylic acid. Epoxy resins used in the synthesis are bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, biphenyl type epoxy resin, hydroquinone from the viewpoint of heat resistance. Type epoxy resin, epoxy resin containing diphenyl sulfide skeleton, phenol aralkyl type polyfunctional epoxy resin, polyfunctional epoxy resin containing naphthalene skeleton, polyfunctional epoxy resin containing dicyclopentadiene skeleton, polyfunctional epoxy resin containing triphenylmethane skeleton, aminophenol type It is desirable to use an epoxy resin, a diaminodiphenylmethane type epoxy resin, or the like. These can be used alone or as a mixture of two or more.

  (D) A compound can be used individually by 1 type or in combination of 2 or more types.

  The compound (d) can be used in a liquid state or in a solid state, but is preferably in a liquid state at 25 ° C. from the viewpoint of low viscosity and workability during blending and processing.

  The compound (d) preferably has an epoxy equivalent and an acrylic equivalent or a methacryl equivalent of 100 or more, and more preferably 150 or more. When epoxy equivalent and acrylic equivalent or methacryl equivalent are smaller than 100, there is a concern that heat resistance is lowered. Furthermore, the molecular weight is preferably 150 or more, and more preferably 200 or more. When the molecular weight is less than 150, there is a risk that the strength may be reduced by volatilizing when heated and contaminating the periphery of the semiconductor device, or by generating bubbles called voids in the cured product.

  As a compounding quantity of the said (d) component, it is desirable to set it as 0.5-20 mass parts with respect to 100 mass parts of total amounts of (a) epoxy resin and (b) hardening | curing agent, More preferably, it is more desirable to set it as 5-15 mass parts. If the blending amount is less than 0.5 parts by mass, the toughening effect may not be sufficiently exhibited, and if it exceeds 20 parts by mass, the heat resistance may decrease.

  The epoxy resin composition of the present invention may further contain an inorganic filler in order to adjust the thermal expansion coefficient. In particular, when the epoxy resin composition of the present invention is used as a resin composition for semiconductor encapsulation, it is preferable to reduce the thermal expansion by blending an inorganic filler. Examples of the inorganic filler include glass, silicon dioxide (silica), aluminum oxide (alumina), titanium oxide (titania), magnesium oxide (magnesia), carbon black, mica, and barium sulfate. In addition, a composite oxide containing two or more types of metal oxides (not just a mixture of two or more types of metal oxides, but the metal oxides are chemically bonded to each other and cannot be separated) Can be used. Examples of the composite oxide include composite oxides composed of silicon dioxide and titanium oxide, silicon dioxide and aluminum oxide, boron oxide and aluminum oxide, silicon dioxide, aluminum oxide, and magnesium oxide. An inorganic filler can be used individually by 1 type or in mixture of 2 or more types.

  As for the particle size of the inorganic filler, it is desirable that the average particle size is 10 μm or less in order to obtain good sealing filling properties when the resin composition is injected. In this case, even if the gap between the semiconductor chip and the substrate is 100 μm or less, sealing and filling can be performed easily. Moreover, in order to adjust the viscosity of a resin composition and the physical property of hardened | cured material, you may use an inorganic filler in combination of 2 or more types from which a particle size differs.

When the epoxy resin composition of the present invention is used as a resin composition for semiconductor encapsulation, it is preferable that the thermal expansion coefficient not higher than the glass transition temperature of the cured product is 60 × 10 ⁻⁶ / ° C. or lower, and 55 × 10. more preferably ^-6 / ° C. or less, even more preferably 50 × ^{10 -6} / ℃ or less. When the thermal expansion coefficient of the cured product is larger than 60 × 10 ⁻⁶ / ° C., stress generated by the expansion and contraction of the resin in the thermal cycle test increases, and connection failure may occur.

  The above-mentioned thermal expansion coefficient was prepared by molding a cured product obtained by heat-treating the epoxy resin composition at 165 ° C. for 2 hours into a size of 2 mm in width, 0.4 mm in thickness, and 40 mm in length. Using TMA / SS6000 (product name) manufactured by Instrument Co., Ltd., the distance between chucks is 20 mm, the measurement temperature range is −50 to 300 ° C., the heating rate is 5 ° C./min, and the tensile force is 0.5 MPa with respect to the film cross-sectional area. It means the average linear expansion coefficient (α1) below the glass transition temperature when measured under the load conditions. Moreover, the glass transition temperature (Tg) of hardened | cured material was shape-processed into the magnitude | size of width 3mm, thickness 0.6mm, and length 40mm of the hardened | cured material obtained by heat-processing an epoxy resin composition at 165 degreeC for 2 hours. Using a DMS6100 (product name) manufactured by Seiko Instruments Inc., a distance between chucks of 20 mm, a frequency of 1 Hz, a measurement temperature range of −50 to 300 ° C., and a heating rate of 5.0 ° C./min. It means the peak temperature of tan δ when tan δ is measured.

  In this embodiment, in order to improve the adhesion between the resin and the inorganic filler and to further improve the connection reliability, the surface of the inorganic filler is preliminarily coupled with a coupling agent such as a silane coupling agent or a titanium coupling agent. It is more preferable to use what was processed by.

  The blending amount of the inorganic filler is appropriately set in order to adjust the viscosity of the epoxy resin composition and the thermal expansion coefficient of the cured product. When using an epoxy resin composition as a resin composition for semiconductor encapsulation, the content of the inorganic filler is desirably 25 to 75% by mass based on the total amount of the epoxy resin composition. When the content of the inorganic filler is less than 25% by mass, it is difficult to reduce the thermal expansion coefficient, and the effect of improving the connection reliability tends to be insufficient. When the content exceeds 75% by mass, the viscosity is high. There is a tendency for workability to be reduced.

  The epoxy resin composition of the present invention may further contain additives such as a silane coupling agent, a titanium coupling agent, an antioxidant, a leveling agent, and an ion trap agent. These additives may be used alone or in combination of two or more. About a compounding quantity, it adjusts so that the effect of each additive may express.

  The epoxy resin composition of the present invention is preferably liquid at 25 ° C. from the viewpoints of workability and workability.

  Moreover, when using the epoxy resin composition of this invention as a resin composition for semiconductor sealing filling, it is desirable that the viscosity of a resin composition is 100 Pa * s or less in 25 degreeC, and it is 70 Pa * s or less. More desirably, it is even more desirably 50 Pa · s or less. When the viscosity of the resin composition exceeds 100 Pa · s, the workability when injecting the resin composition tends to be lowered.

  The epoxy resin composition of the present invention can be used for, for example, a potting material, a casting resin, an insulating resin, etc. in addition to the semiconductor sealing filling resin composition.

  The epoxy resin composition of the present invention can be prepared by stirring and mixing the above-described components using a planetary mixer, a raking machine, a ball mill, an automatic mortar, or the like. When blending the solid component, it is preferable to mix after dissolving the liquid component uniformly in advance. Moreover, when mix | blending an inorganic filler, it is preferable to knead | mix using 3 rolls and to disperse | distribute an inorganic filler in a resin composition.

  Next, the semiconductor device manufactured using the resin composition for semiconductor sealing filling of this invention is demonstrated.

  FIG. 1 is a schematic cross-sectional view showing an embodiment of a semiconductor device according to the present invention. A semiconductor device 10 shown in FIG. 1 includes a circuit board 7, a semiconductor element 5, and a sealing resin 6 disposed between the circuit board 7 and the semiconductor element 5. The sealing resin 6 is made of a cured product of the resin composition for semiconductor sealing filling of the present invention and seals the gap between the circuit board 7 and the semiconductor element 5. The circuit board 7 includes a board such as an interposer and wiring 4 provided on one surface of the board. The wiring 4 of the circuit board 7 and the semiconductor element 5 are electrically connected by a plurality of bumps 3. The circuit board 7 has an electrode pad 2 and a solder ball 1 provided on the electrode pad 2 on the surface opposite to the surface on which the wiring 4 is provided, and is connected to other circuit members. Is possible.

  For the circuit board 7, for example, a metal layer made of a metal material such as copper is formed on a board made of an insulating material such as glass epoxy, polyimide, polyester, or ceramic, and unnecessary portions of the metal layer are removed by etching. A wiring pattern can be used, or a wiring pattern can be formed by printing a conductive material on the substrate surface. A metal layer made of low melting point solder, high melting point solder, tin, indium, gold, nickel, silver, copper, palladium, or the like may be formed on the surface of the wiring 4. This metal layer may be composed of only a single component or may be composed of a plurality of components. Moreover, you may have the structure where the some metal layer was laminated | stacked. In the present embodiment, the circuit board 7 may be a semiconductor element (semiconductor chip).

  The semiconductor element 5 is not particularly limited, and various semiconductors such as elemental semiconductors such as silicon and germanium, and compound semiconductors such as gallium arsenide and indium phosphide can be used.

  Examples of the material of the bump 3 include low melting point solder, high melting point solder, tin, indium, gold, silver, and copper. The bump 3 may be composed of only a single component or may be composed of a plurality of components. The bump 3 may have a laminated structure including a metal layer made of these components. The bump may be formed on the semiconductor element, may be formed on the substrate, or may be formed on both the semiconductor element and the substrate.

  As a semiconductor device according to the present invention, a semiconductor chip mounted on a substrate called an interposer and sealed with a resin as in the semiconductor package shown in FIG. Size package) and BGA (ball grid array). Another semiconductor package includes a semiconductor chip that can be mounted on a substrate without using an interposer by rewiring the electrode part of the semiconductor chip on the surface of the semiconductor chip. What is called a package. Examples of the substrate on which the semiconductor package according to the present invention is mounted include a normal circuit substrate, and this substrate refers to what is called a mother board with respect to the interposer.

  Next, a method for manufacturing a semiconductor device according to the present invention will be described. The method described below is an example using a semiconductor chip on which solder bumps are formed, but the method for manufacturing a semiconductor device according to the present invention is not limited to this method.

  (1) After applying rosin-based flux to the surface of solder bumps formed on a semiconductor chip using a flux coating device, the semiconductor chip and the substrate are aligned using a chip mounter, and the semiconductor chip is bonded by pressure bonding. It is arranged at a predetermined position on the substrate.

(2) Using a reflow apparatus, heat treatment is performed with a predetermined heating profile, and solder bumps are melted to flip-chip connect the semiconductor chip and the substrate.

(3) After the flux residue is washed with a solvent, the resin composition for semiconductor sealing filling of the present invention is dropped in a state heated to 100 to 120 ° C., and capillary action is caused in the gap between the semiconductor chip and the substrate. Inject using.

(4) After the injection is completed, in order to cure the resin composition for sealing filling, heat treatment is performed for 0.5 to 2 hours in a heating oven heated to 150 to 175 ° C.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not restrict | limited to these.

<Synthesis of modifier>
(Synthesis Example 1)
In a 500 mL flask equipped with a stirrer, a thermometer, and a nitrogen substitution device, 187 g of liquid high-purity bisphenol A type liquid epoxy (YL-980, product name, epoxy equivalent 187 manufactured by Japan Epoxy Resin Co., Ltd.), 36 g of acrylic acid ( Equivalent ratio (number of carboxyl groups in acrylic acid / number of epoxy groups in epoxy resin): 0.5), 0.5 g of triphenylphosphine, and 0.15 g of hydroquinone were added, and the mixture was added at 100 ° C. for 7 hours under a nitrogen atmosphere. By stirring and mixing, a modifier 1 containing a compound having an acrylic group and an epoxy group in the molecule was obtained. When the acid value of the modifier 1 was measured by titrating with an ethanol solution of potassium hydroxide, the acid value was 0.3 KOHmg / g or less, and it was confirmed that no acrylic acid remained.

<Preparation of epoxy resin composition>
(Examples 1 to 3 and Comparative Examples 1 and 2)
Each component was mixed using a rake machine so as to have the composition shown in Table 1 (unit: parts by mass), and then vacuum degassed to prepare epoxy resin compositions.

(Examples 4 to 6 and Comparative Examples 3 and 4)
Each constituent component was kneaded and dispersed using three rolls so as to have the composition (unit: part by mass) shown in Table 2, and then vacuum degassed to prepare epoxy resin compositions containing inorganic fillers.

In addition, the detail of each used component is as follows.
Epoxy resin 1: Bisphenol F type liquid epoxy resin YDF-8170C (product name, epoxy equivalent 159 manufactured by Toto Kasei Co., Ltd.).
Epoxy resin 2: aminophenol type liquid epoxy resin E630LSD (product name, epoxy equivalent 95, manufactured by Japan Epoxy Resin Co., Ltd.).
Curing agent: 3,3′-diethyl-4,4′-diaminodiphenylmethane KAYAHARD-AA (product name, manufactured by Nippon Kayaku Co., Ltd., active hydrogen equivalent 63).
Curing accelerator: 2-phenyl-4-methyl-5-hydroxymethylimidazole 2P4MHZ (product name, manufactured by Shikoku Kasei Kogyo Co., Ltd.).
Modifier A-1: Flexible epoxy resin YL7175-500 (product name manufactured by Japan Epoxy Resin Co., Ltd., epoxy equivalent 475, epoxy group in the molecule having a glycidyl ether structure with an alcoholic hydroxyl group).
Modifier B-1: The one obtained in Synthesis Example 1 (Modifier 1).
Modifier B-2: Dipentaerythritol hexaacrylate A-DPH (product name, manufactured by Shin-Nakamura Chemical Co., Ltd.).
Modifier B-3: Tris (2-acryloyloxyethyl) isocyanurate A-9300 (product name, Shin-Nakamura Chemical Co., Ltd.).
Coupling agent: KBM403 (manufactured by Shin-Etsu Chemical Co., Ltd., product name).
Inorganic filler 1: spherical silica SE2050 (manufactured by Admatechs Co., Ltd., product name, average particle size 0.5 μm).
Inorganic filler 2: Spherical silica SE5050 (product name, average particle size of 1.5 μm).

<Evaluation of epoxy resin composition>
For the epoxy resin compositions of Examples 1 to 3 and Comparative Examples 1 and 2, the breaking energy, breaking strain, and glass transition temperature (Tg) were measured according to the methods shown below. The obtained results are shown in Table 1. For the epoxy resin compositions of Examples 4 to 6 and Comparative Examples 3 and 4, according to the method shown below, fracture toughness value K _IC , viscosity, elastic modulus, Tg, thermal expansion coefficients α1 and α2, and The adhesive force was measured. The obtained results are shown in Table 2.

[Measurement of breaking energy and breaking strain]
A cured product obtained by heat-treating the epoxy resin composition at 165 ° C. for 2 hours was prepared by molding a cured product having a width of 1.8 mm, a thickness of 2.1 mm, and a length of 35 mm. Measure the stress-strain curve until it breaks in a three-point bending test using a Microtester 5548 manufactured by Instron at a measurement temperature of 25 ° C. at 20 mm, a crosshead speed of 3.0 mm / min, and determine the area under the curve. The breaking energy was calculated by calculation. Moreover, the breaking strain was read from the stress-strain curve. Note that the stress σ (unit MPa) and the strain ε (dimensionless) are the width of the measurement cured product b (mm), the thickness h (mm), the fulcrum distance L (mm), and the load F (N ) Is Y (mm),
Stress σ = (3 × F × L) / (2 × b × h ² )
Strain ε = Y × 6h / L ²
It was calculated by the following formula.

[Measurement of fracture toughness value K _IC ]
The fracture toughness value K _IC was calculated according to the following procedure.

A cured product obtained by heat-treating the epoxy resin composition at 165 ° C. for 2 hours was molded into a shape having a length of 60 mm, a thickness T = 12.5 mm, a width W = 4 mm, and a notch depth D = 2 mm. A load-displacement curve was measured by a three-point bending test using an Instron Microtester 5548 under the conditions of a distance L = 50 mm, a crosshead speed of 0.5 mm / min, and a measurement temperature of 25 ° C. P (unit N) was recorded. From these values, the fracture toughness value K _IC (unit: MPa · m ^1/2 ) was calculated by the following equation.
K _IC = σ × (π × D) ^1/2 × F (D / T)
σ = 3 × L × (P / W) / (2 × T ² )
When D / T = ξ and L / T = 4, F (ξ) ≈1.090−1.735ξ + 8.20ξ ² -14.18ξ ³ + 14.57ξ ⁴

[Measurement of viscosity]
About the epoxy resin composition, the viscosity in 25 degreeC was measured at the rotation speed of 5 rpm using the E-type viscosity meter (made by Tokyo Keiki Co., Ltd.).

[Measurement of Elastic Modulus and Glass Transition Temperature (Tg)]
A cured product obtained by heat-treating the epoxy resin composition at 165 ° C. for 2 hours was prepared by molding into a size of 3 mm in width, 0.6 mm in thickness, and 40 mm in length. DMS6100 manufactured by Seiko Instruments Inc. Product name), the storage elastic modulus, loss elastic modulus, and tan δ are measured under the conditions of a chuck distance of 20 mm, a frequency of 1 Hz, a measurement temperature range of −50 to 300 ° C., and a heating rate of 5.0 ° C./min. went. At this time, the storage elastic modulus at 25 ° C. and 260 ° C., and the peak temperature of tan δ were read as the glass transition temperature (Tg).

[Measurement of thermal expansion coefficient]
A cured product obtained by heat-treating the epoxy resin composition at 165 ° C. for 2 hours was prepared by molding into a size of 2 mm in width, 0.4 mm in thickness, and 40 mm in length, and TMA / manufactured by Seiko Instruments Inc. Using SS6000 (product name), measurement is performed under the conditions of a distance between chucks of 20 mm, a measurement temperature range of −50 to 300 ° C., a heating rate of 5 ° C./min, and a tensile load of 0.5 MPa with respect to the film cross-sectional area. The average linear expansion coefficient (α1) below the glass transition temperature and the average linear expansion coefficient (α2) above the glass transition temperature were read. In addition, the glass transition temperature at this time is a value obtained by measurement of said glass transition temperature (Tg).

[Measurement of adhesive strength]
Silicone rubber plate with a hole of 3mm in diameter at the center of 10mm in length × 10mm in width × 1mm in thickness was bonded to the polyimide coated surface of a 10mm vertical x 10mm wide x 0.55mm thick silicon chip coated with polyimide. The thing was arrange | positioned on the hotplate set to 125 degreeC, and the epoxy resin composition was filled so that the inside of the hole of a silicone rubber plate might be filled. Next, the epoxy resin composition was cured by heat treatment at 165 ° C. for 2 hours, and then the silicone rubber plate was peeled off to prepare a sample for measuring an adhesive force. This sample for measurement was subjected to a shear test with a bond tester 4000 manufactured by Daisy under the conditions of a shear rate of 0.05 mm / second, a shear height of 0.05 mm, and a measurement temperature of 260 ° C., and an initial adhesive force was measured. Moreover, after leaving the measurement sample in a constant temperature and humidity chamber set at 85 ° C. and a relative humidity of 85% for 48 hours, the same shear test was performed to measure the adhesive force after moisture absorption.

  As shown in Table 1, the epoxy resin compositions of Examples 1 to 3 in which the modifier A-1 and any one of the modifiers B-1 to 3 are blended are more remarkable than the comparative example 1. An improvement in breaking strain and breaking energy and an increase in glass transition temperature were observed.

As shown in Table 2, the epoxy resin compositions of Examples 4 to 6, in which the modifier A-1 and any one of the modifiers B-1 to B-3 are blended and an inorganic filler is blended, expansion coefficient, viscosity, elastic modulus, for adhesion is yet approximately equal to Comparative example 3 containing no modifier, it was confirmed that improvement and increase of the glass transition temperature of the K _IC is reached. From this, when the epoxy resin composition of Examples 4-6 was used for semiconductor sealing filling, it turned out that the sealing resin excellent in toughness and heat resistance can be formed.

DESCRIPTION OF SYMBOLS 1 ... Solder ball, 2 ... Electrode pad, 3 ... Bump, 4 ... Wiring, 5 ... Semiconductor chip, 6 ... Sealing resin, 7 ... Circuit board, 10 ... Semiconductor device.

Claims (8)

  An epoxy resin composition comprising (a) an epoxy resin, (b) a curing agent, (c) a flexible epoxy resin, and (d) a compound having an acryl group or a methacryl group.   The epoxy resin composition according to claim 1, wherein the compound (d) is a compound having an acrylic group or a methacryl group and an epoxy resin.   The epoxy resin composition according to claim 1 or 2, wherein the (b) curing agent is an aromatic amine compound having a primary or secondary amino group.   The epoxy resin composition according to any one of claims 1 to 3, further comprising an inorganic filler.   The epoxy resin composition according to any one of claims 1 to 4, which is liquid at 25 ° C.   The resin composition for semiconductor sealing filling which consists of an epoxy resin composition as described in any one of Claims 1-5.   The semiconductor device manufactured by sealing a semiconductor element using the resin composition for semiconductor sealing filling of Claim 6. A circuit board, a semiconductor element electrically connected to the circuit board, and a cured product of the resin composition for semiconductor sealing filling according to claim 6, wherein a gap between the circuit board and the semiconductor element is formed. And a sealing resin for sealing.

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