Epoxy resin composition, cured product, semiconductor device, and method for manufacturing a semiconductor device.

Abstract

The present invention provides an epoxy resin composition that yields a cured product that is less prone to peeling from copper pillars. It also provides a cured product of the epoxy resin composition, a semiconductor device comprising the cured product, and a method for manufacturing the same. Epoxy resin (A), Hardener (B), and An epoxy resin composition containing an inorganic filler (C), The glass transition temperature of the cured product is 120-220°C. An epoxy resin composition having a storage modulus of 6.0 GPa or higher at 25°C for the cured product.

Description

Technical Field

[0001] The present invention relates to an epoxy resin composition, a cured product, a semiconductor device, and a method for manufacturing a semiconductor device.

Background Art

[0002] In recent years, with the miniaturization, weight reduction, and high performance of electronic devices, the mounting form of semiconductors has been shifting from the wire bond type to the flip chip type. A flip chip type semiconductor device has a structure in which an electrode portion on a substrate and a semiconductor element are connected via bumps. In addition, a semiconductor encapsulant called underfill is used to protect the connected semiconductor element, substrate, and bumps (Patent Document 1). This underfill is filled between the semiconductor element and the substrate and further seals the semiconductor element by heat curing.

[0003] From the perspective of protecting semiconductor elements and the like, generally, an inorganic filler such as a silica filler or aluminum oxide is blended into the underfill. By blending an inorganic filler into the underfill, it is possible to protect the bumps from stress caused by deformation of the semiconductor device, physical impacts such as dropping, and thermal shock in the reflow process, and effectively prevent poor connection between the semiconductor element and the substrate.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, when the resin composition described in Patent Document 1 was used as an underfill material, there was a problem in that the cured material peeled off from the copper pillars during the reflow process. Figure 4 is a magnified image of a cross-section of a primary mounting substrate, where 31 is the copper pillar, 32 is the cured underfill material, 33 is the solder, and 34 is the area where the cured material and the copper pillars have peeled off. The upper part of the figure is the electronic components, and the lower part is the substrate. Figures 4(a) and (b) are images of the state in which peeling has occurred, and (b) is a magnified image of the peeled area in (a). (c) is an image of the primary mounting substrate before reflow, and is a magnified image of the same area as (b). When the cured material peels off from the copper pillars, the reliability of the semiconductor device is greatly reduced. For this reason, the cured underfill material is required to have low peelability from the copper pillars, that is, high adhesion and bonding to the copper pillars.

[0006] Therefore, an object of the present invention is to provide an epoxy resin composition that yields a cured product that is less prone to peeling from copper pillars. Furthermore, an object of the present invention is to provide a cured product of the epoxy resin composition, a semiconductor device comprising the cured product, and a method for manufacturing the same. In this specification, the properties of a cured product that is less prone to peeling from copper pillars, and the epoxy resin composition that yields the cured product, may be described as "low peelability." [Means for solving the problem]

[0007] The inventors of this invention, after diligent research to achieve the above objectives, have found that the above problems can be solved by using a composition having a specific configuration. This invention was completed based on these findings.

[0008] In other words, in the present invention, Epoxy resin (A), Hardener (B), and An epoxy resin composition containing an inorganic filler (C), The glass transition temperature of the cured product is 120-220°C. The present invention provides an epoxy resin composition in which the storage modulus of the cured product at 25°C is 6.0 GPa or higher.

[0009] The epoxy resin composition described above preferably has a coefficient of linear expansion of less than 29 ppm / °C at 0 to 20°C.

[0010] The epoxy resin composition described above preferably contains a glycidylamine-type epoxy resin as epoxy resin (A).

[0011] The number of functional groups in the above-mentioned glycidylamine-type epoxy resin is preferably three or more.

[0012] The epoxy resin composition described above preferably contains an amine-based curing agent (B3) as the curing agent (B).

[0013] The epoxy resin composition described above preferably contains an aromatic amine as the curing agent (B).

[0014] The epoxy resin composition preferably contains, as the inorganic filler (C), an inorganic filler (C1) having an average particle size of 0.1 to 10 μm and an inorganic filler (C2) having an average particle size of 1 nm or more and less than 100 nm.

[0015] The average particle size of the inorganic filler (C1) is preferably 0.1 to 3 μm.

[0016] In the epoxy resin composition described above, it is preferable that the content of inorganic filler (C1) relative to epoxy resin (A) (100% by mass) is 60% by mass or more.

[0017] The epoxy resin composition described above preferably does not contain styrene-butadiene compounds and PMMA-PnBA block polymers.

[0018] The epoxy resin composition described above is preferably free of phosphoric acid or free of phosphate polyester.

[0019] The epoxy resin composition described above preferably does not contain a silicone resin having two or more epoxy groups in one molecule as the epoxy resin (A).

[0020] The above epoxy resin composition preferably has a viscosity at 25°C of 1.0 to 200 Pa·s.

[0021] In the peel test under predetermined conditions, the above epoxy resin composition preferably has a peel rate of less than 60% when reflow is performed 5 times.

[0022] The above epoxy resin composition preferably has a thixotropic index value (TI value) at 25°C of 0.3 to 2.

[0023] The above epoxy resin composition is preferably used for semiconductor encapsulation.

[0024] The above epoxy resin composition is preferably an underfill material.

[0025] The present invention also provides a cured product of the above epoxy resin composition.

[0026] In the present invention, a substrate, an electronic component disposed on the above substrate, the cured product that encapsulates the above electronic component, and also provides a semiconductor device including the above components.

[0027] In the present invention, a step of filling the gap between the substrate and the electronic component disposed on the above substrate with the above epoxy resin composition, a step of heating and curing the above epoxy resin composition, and also provides a method for manufacturing a semiconductor device including the above steps.

Advantages of the Invention

[0028] The epoxy resin composition of the present invention provides a cured product in which peeling from copper pillars hardly occurs. Further, since the cured product of the above epoxy resin composition has excellent low peelability, the semiconductor device including the cured product exhibits high reliability. [Brief explanation of the drawing]

[0029] [Figure 1] This figure shows an embodiment of the method for manufacturing a semiconductor device according to the present invention. [Figure 2] This figure shows an embodiment of the method for manufacturing a semiconductor device according to the present invention. [Figure 3] This figure shows an embodiment of the method for manufacturing a semiconductor device according to the present invention. [Figure 4] This is a magnified image of the cross-section of the primary mounting board. [Modes for carrying out the invention]

[0030] (Epoxy resin composition) The epoxy resin composition of the present invention comprises an epoxy resin (A), a curing agent (B), and an inorganic filler (C), and is characterized in that the glass transition temperature of the cured product is 120 to 220°C, and the storage modulus of the cured product at 25°C is 6.0 GPa or higher.

[0031] The glass transition temperature (Tg) of the cured epoxy resin composition is not particularly limited as long as it is between 120 and 220°C, but is preferably 124°C or higher, more preferably 130°C or higher, even more preferably 135°C or higher, even more preferably 140°C or higher, even more preferably 145°C or higher, and particularly preferably 150°C or higher. Also, is preferably 215°C or lower, more preferably 210°C or lower, even more preferably 205°C or lower, even more preferably 200°C or lower, even more preferably 195°C or lower, and particularly preferably 190°C or lower. When the glass transition temperature is within the above range, the adhesion between the cured product and the copper pillar is improved and the peelability tends to decrease further. The cured product is obtained by curing the epoxy resin composition at 165°C for 120 minutes. The glass transition temperature can be measured by the method described in the examples below.

[0032] The storage modulus of the cured epoxy resin composition at 25°C is not particularly limited as long as it is 6.0 GPa or higher, but for example, 6.3 GPa or higher is preferred, more preferably 6.6 GPa or higher, even more preferably 7.0 GPa or higher, even more preferably 7.3 GPa or higher, even more preferably 7.6 GPa or higher, even more preferably 7.8 GPa or higher, even more preferably 7.9 GPa or higher, and particularly preferably 8 GPa or higher. Also, for example, it is preferred to be 20 GPa or less, more preferably 15 GPa or less, even more preferably 12 GPa or less, even more preferably 11 GPa or less, and particularly preferably 10 GPa or less. When the storage modulus is within the above range, the adhesion between the cured product and the copper pillar is improved and peelability tends to decrease further. The cured product is obtained by curing the epoxy resin composition at 165°C for 120 minutes. The storage modulus can be measured by the method described in the examples below.

[0033] In the cured product of the epoxy resin composition described above, the coefficient of linear expansion CTE (ppm / °C) at 0 to 20°C is not particularly limited, but is preferably less than 30 ppm / °C, more preferably less than 29 ppm / °C, even more preferably less than 28.5 ppm / °C, and particularly preferably less than 28 ppm / °C. Alternatively, it is preferably 10 ppm / °C or higher, more preferably 15 ppm / °C or higher, even more preferably 20 ppm / °C or higher, and particularly preferably 24 ppm / °C or higher. A coefficient of linear expansion within the above range tends to result in reduced peelability. The coefficient of linear expansion can be measured by the method described in the examples below.

[0034] • Epoxy resin (A) The above epoxy resin composition, by containing epoxy resin (A), can form a cured product with high electrical insulation properties. The number of epoxy groups in epoxy resin (A) is not particularly limited as long as it is one or more, but it is preferable that it is two or more, that is, that it is a polyfunctional type epoxy resin. Epoxy resin (A) can be used alone or in combination of two or more types.

[0035] The epoxy resin (A) may be liquid or solid at room temperature (25°C), but it is preferable that it be liquid from the viewpoint of the viscosity of the epoxy resin composition. Even a solid epoxy resin can be preferably used if it exhibits a liquid state as a mixture when used in combination with a liquid epoxy resin. Examples of solid epoxy resins include epoxy compounds having liquid crystalline properties. The above epoxy resin composition may contain epoxy compounds having liquid crystalline properties, but these compounds do not need to be used because they have a high melting point, are difficult to melt, and have high viscosity even at high temperatures.

[0036] The epoxy resin (A) is not particularly limited, but examples include bisphenol type epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin, bixylenol type epoxy resin, cyclohexane type epoxy resin (e.g., 1,4-glycidylcyclohexane), dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, naphthol novolac type epoxy resin, phenol novolac type epoxy resin, tert-butyl-catechol type epoxy resin, naphthalene type epoxy resin, Examples include naphthol-type epoxy resins, anthracene-type epoxy resins, glycidylamine-type epoxy resins, glycidyl ester-type epoxy resins, cresol novolac-type epoxy resins, biphenyl-type epoxy resins, aliphatic epoxy resins, epoxy resins having a butadiene structure, alicyclic epoxy resins, heterocyclic epoxy resins, spiro-ring-containing epoxy resins, cyclohexanedimethanol-type epoxy resins, naphthylene ether-type epoxy resins, trimethylol-type epoxy resins, tetraphenylmethane-type epoxy resins, aminophenol-type epoxy resins, and silicone-modified epoxy resins.

[0037] From the viewpoint of reducing peelability, the epoxy resin composition described above preferably contains at least one selected from bisphenol-type epoxy resins such as bisphenol F-type epoxy resin and bisphenol A-type epoxy resin, cyclohexane-type epoxy resins such as 1,4-glycidylcyclohexane, glycidylamine-type epoxy resins, and naphthalene-type epoxy resins as epoxy resin (A), and more preferably contains glycidylamine-type epoxy resin. Furthermore, the number of functional groups of the glycidylamine-type epoxy resin is not particularly limited, but is preferably 3 or more, and preferably 3. Also, for example, is preferably 15 or less, more preferably 12 or less, even more preferably 9 or less, even more preferably 6 or less, and particularly preferably 4 or less.

[0038] The content of epoxy resin (A) in the above epoxy resin composition (100% by mass) is not particularly limited, but is preferably 4% by mass or more, more preferably 8% by mass or more, even more preferably 10% by mass or more, even more preferably 12% by mass or more, even more preferably 16% by mass or more, and particularly preferably 20% by mass or more. Also, is preferably 60% by mass or less, more preferably 50% by mass or less, even more preferably 45% by mass or less, even more preferably 40% by mass or less, and particularly preferably 35% by mass or less. When the content of epoxy resin (A) is within the above range, the epoxy resin composition tends to have excellent injectability.

[0039] The epoxy resin composition described above may contain 1,6-hexanediol diglycidyl ether, but it may be omitted because it tends to make it difficult to adjust the glass transition temperature and coefficient of thermal expansion.

[0040] The above epoxy resin composition may contain a silicone-modified epoxy resin (a silicone resin having two or more epoxy groups in one molecule), but it is preferable that it is not included from the viewpoint of component compatibility in the composition.

[0041] The epoxy resin composition described above may contain 4,4'-methylenebis(N,N-diglycidylaniline), but it may be omitted because it increases the crosslinking density of the cured product, resulting in a cured product with high rigidity and high Tg, which may prevent the relaxation of stresses near bumps.

[0042] The epoxy resin composition described above may contain 4,4'-[1,4-phenylenebis(dimethylmethylene)]bis(N,N-bisglycidyl-2,6-dimethylaniline), but it may be omitted because it increases the crosslinking density of the cured product, resulting in a cured product with high rigidity and high Tg, which may prevent the relaxation of stresses near bumps.

[0043] In the epoxy resin composition described above, the content of epoxy resin having four or more epoxy groups relative to epoxy resin (A) (100% by mass) is not particularly limited, but is preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 10% by mass or less, and particularly preferably 5% by mass or less. By having an epoxy resin content of four or more epoxy groups within the above range, the crosslinking density of the cured product does not become too high, so the rigidity and Tg of the cured product are moderately low, and the stress applied near the bump tends to be relieved.

[0044] Specific examples of liquid epoxy resins include "YDF-8170" and "YDF870GS" (both bisphenol F type epoxy resins), "YDF-8125" (bisphenol A type epoxy resin), "ZX-1658" and "ZX-1658GS" (both liquid 1,4-glycidylcyclohexane) from Nippon Steel Chemical & Material Co., Ltd.; "HP-4032," "HP-4032D," and "HP-4032SS" (all naphthalene type epoxy resins) from DIC Corporation; and "jER828US" and "jER828EL" from Mitsubishi Chemical Corporation. (All are bisphenol A type epoxy resins), "jER806", "jER807" (All are bisphenol F type epoxy resins), "jER152" (phenol novolac type epoxy resin), "jER630", "jER630LSD" (All are glycidylamine type epoxy resins), "YX7400N" (aliphatic epoxy resin / polytetramethylene glycol diglycidyl ether); "Epogosei PT" (polytetramethylene glycol diglycidyl ether) from Yokkaichi Gosei Co., Ltd.; "ZX105" from Nippon Steel & Sumitomo Metal Chemical Co., Ltd. 9 (a mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin); "EX-721" (glycidyl ester type epoxy resin) and "EX171" (lauryl alcohol (EO) 15 glycidyl ether) manufactured by Nagase ChemteX Corporation; "ADEKA Resin EP4005" (bisphenol A type epoxy resin containing polypropylene glycol structure), "EP-3950L", and "EP-3980S" (both glycidylamine type epoxy resins) manufactured by ADEKA Corporation; "AER9000" (PO-modified bisphenol F) manufactured by Asahi Kasei Corporation Examples include oxazolidone ring-containing epoxy resins (e.g., "AER4001", "AER4004", "AER4152"); "DER852", "DER858" (both oxazolidone ring-containing epoxy resins) from Dow Chemical Ltd.; "FAE-2500", "EPPN-501HY" (both trisphenolmethane-type epoxy resins) and "RE410S" (bisphenol A-type epoxy resin) from Nippon Kayaku Co., Ltd.; and "Celoxide 2021P" (alicyclic epoxy resin) from Daicel Corporation.

[0045] Specific examples of solid epoxy resins include DIC Corporation's "HP-4032H" (naphthalene-type epoxy resin), "HP-4700", "HP-4710" (both naphthalene-type tetrafunctional epoxy resins), "N-690" (cresol novolac-type epoxy resin), "N-695" (cresol novolac-type epoxy resin), "HP-7200", "HP-7200L", "HP-7200HH", "HP-7200H", and "HP-7200HHH". (All are dicyclopentadiene type epoxy resins), "EXA850CRP", "EXA7311", "EXA7311-G3", "EXA7311-G4", "EXA7311-G4S", "HP6000" (All are naphthylene ether type epoxy resins); Nippon Kayaku Co., Ltd.'s "EPPN-502H" (trisphenolmethane type epoxy resin), "NC-7000-L" (naphthol novolac type epoxy resin), "NC-3000-H", "NC Examples include "-3000", "NC-3000-L", and "NC-3100" (all biphenyl-type epoxy resins); "ESN475V" (naphthol-type epoxy resin) and "ESN485" (naphthol novolac-type epoxy resin) from Nippon Steel Chemical & Material Co., Ltd.; "YX4000H" and "YL6121" (both biphenyl-type epoxy resins), "YX4000HK" (bixylenol-type epoxy resin), "YL7760" (bisphenol AF-type epoxy resin), and "YX8800" (anthracene-type epoxy resin) from Mitsubishi Chemical Corporation; "PG-100" and "CG-500" from Osaka Gas Chemical Co., Ltd.; and "YL7800" (fluorene-type epoxy resin), "jER1010" (solid bisphenol A-type epoxy resin), "jER1031S" (tetraphenylethane-type epoxy resin), and "jER157S70" (bisphenol novolac-type epoxy resin) from Mitsubishi Chemical Corporation.

[0046] The epoxy equivalent of epoxy resin (A) is not particularly limited, but is preferably 30 to 800 g / eq, more preferably 40 to 600 g / eq, even more preferably 50 to 400 g / eq, even more preferably 60 to 300 g / eq, and most preferably 80 to 200 g / eq.

[0047] The content of epoxy resin (A) in the above epoxy resin composition (100% by mass) is not particularly limited, but is preferably 4% by mass or more, more preferably 8% by mass or more, even more preferably 10% by mass or more, even more preferably 12% by mass or more, even more preferably 16% by mass or more, and particularly preferably 20% by mass or more. Also, is preferably 60% by mass or less, more preferably 50% by mass or less, even more preferably 45% by mass or less, even more preferably 40% by mass or less, and particularly preferably 35% by mass or less. When the content of epoxy resin (A) is within the above range, the epoxy resin composition tends to have excellent injectability.

[0048] The content of glycidylamine-type epoxy resin in the above epoxy resin composition (100% by mass) is not particularly limited, but is preferably 0.5% by mass or more, more preferably 1% by mass or more, even more preferably 2% by mass or more, even more preferably 4% by mass or more, even more preferably 8% by mass or more, and particularly preferably 16% by mass or more. Alternatively, it is preferably 50% by mass or less, more preferably 40% by mass or less, even more preferably 35% by mass or less, and particularly preferably 30% by mass or less. When the content of glycidylamine-type epoxy resin is within the above range, the epoxy resin composition tends to have excellent low peelability.

[0049] The content of glycidylamine-type epoxy resin relative to epoxy resin (A) (100% by mass) in the above epoxy resin composition is not particularly limited, but is preferably 1% by mass or more, more preferably 2% by mass or more, even more preferably 4% by mass or more, even more preferably 8% by mass or more, even more preferably 16% by mass or more, even more preferably 24% by mass or more, and particularly preferably 32% by mass or more. Also, is preferably 95% by mass or less, more preferably 90% by mass or less, even more preferably 80% by mass or less, even more preferably 70% by mass or less, and particularly preferably 60% by mass or less. When the content of glycidylamine-type epoxy resin is within the above range, the epoxy resin composition tends to have excellent low peelability.

[0050] • Hardener (B) The curing agent (B) is not particularly limited, but examples include phenolic curing agents (B1), acid anhydride curing agents (B2), amine curing agents (B3), and imidazole curing agents (B4). From the viewpoint of low release properties, the epoxy resin composition preferably contains an amine curing agent (B3) as the curing agent (B). The curing agent (B) can be used alone or in combination of two or more types.

[0051] The phenolic curing agent (B1) may be any monomer, oligomer, or polymer having a phenolic hydroxyl group. Examples include phenol novolac resin, alkylated phenol novolac resin, allylated phenol novolac resin, cresol novolac resin, phenol aralkyl resin (e.g., resin containing a phenylene skeleton and / or biphenylene skeleton), naphthol aralkyl resin, triphenolmethane resin, and dicyclopentadiene type phenolic resin. The phenolic curing agent (B1) may be liquid or solid at room temperature (25°C), but it is preferable to be liquid from the viewpoint of workability in epoxy resin compositions.

[0052] Acid anhydride-based curing agents (B2) are curing agents having one or more acid anhydride groups in one molecule. Acid anhydride-based curing agents (B2) include acid anhydrides, hydrogenated acid anhydrides, and derivatives of acid anhydrides, such as phthalic anhydride-based curing agents, succinic anhydride-based curing agents, and glutaric anhydride-based curing agents.

[0053] The above-mentioned phthalic anhydride-based curing agent is a curing agent having a skeleton derived from phthalic anhydride within its molecule. The above-mentioned phthalic anhydride-based curing agent is not particularly limited, but examples include phthalic anhydrides which may have substituents (preferably hydrocarbon groups) such as trimellitic anhydride, pyromellitic anhydride, and bensophenonetetracarboxylic dianhydride; and hydrogenated phthalic anhydrides which may have substituents (preferably hydrocarbon groups, more preferably alkyl or alkenyl groups) such as tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, 3,4-dimethyl-6-(2-methyl-1-propenyl)-4-cyclohexene-1,2-dicarboxylic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, and nadic anhydride. The succinic anhydride-based curing agent described above is not particularly limited, but examples include succinic anhydrides which may have substituents (preferably hydrocarbon groups, more preferably alkyl or alkenyl groups). The glutaric anhydride-based curing agent described above is not particularly limited, but examples include glutaric anhydrides which may have substituents (preferably hydrocarbon groups, more preferably alkyl or alkenyl groups).

[0054] Examples of amine-based curing agents (B3) include aromatic amines such as 4,4'-diamino-3,3'-diethyldiphenylmethane, 4,4'-methylenebis(2-ethylaniline), diethyltoluenediamine, dimethylthiotoluenediamine, methylenedianiline, m-phenylenediamine, 4,4'-diaminodiphenylsulfone, and 3,3'-diaminodiphenylsulfone.

[0055] Examples of imidazole-based curing agents (B4) include 2-methylimidazole, 2-undecylimidazole, 1-cyanoethyl-2-undecylimidazole, 2-heptadecylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-ethyl-4-imidazole, 2-phenylimidazole, and 2-phenyl-4-methylimidazole. Microencapsulated imidazole-based curing agents are also an example of imidazole-based curing agents (B4).

[0056] The curing agent equivalent (molecular weight per functional group of the curing agent, e.g., active hydrogen equivalent) of curing agent (B) is not particularly limited, but is preferably 10 to 300 g / eq, more preferably 20 to 200 g / eq, and even more preferably 30 to 100 g / eq.

[0057] The amount of curing agent (B) is not particularly limited, but it is preferably such that the stoichiometric equivalent ratio (curing agent equivalent / epoxy group equivalent) with the epoxy resin (A) is, for example, 0.5 to 1.5, and more preferably 0.8 to 1.2.

[0058] The content of the curing agent (B) in the epoxy resin composition (100% by mass) is not particularly limited, but is preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 6% by mass or more, even more preferably 8% by mass or more, even more preferably 9% by mass or more, and particularly preferably 9.5% by mass or more. Also, is preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 15% by mass or less, and particularly preferably 12% by mass or less. When the content of the curing agent (B) is within the above range, the curability and low peelability tend to improve.

[0059] The content of the curing agent (B) relative to the epoxy resin (A) (100% by mass) in the above epoxy resin composition is not particularly limited, but is preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 24% by mass or more, even more preferably 28% by mass or more, and particularly preferably 32% by mass or more. Alternatively, it is preferably 100% by mass or less, more preferably 80% by mass or less, even more preferably 60% by mass or less, even more preferably 50% by mass or less, and particularly preferably 45% by mass or less. When the content of the curing agent (B) is within the above range, the curability and low peelability tend to improve.

[0060] ·Inorganic filler (C) The inorganic filler (C) is not particularly limited, but it is preferable that it (1) has the property of suppressing volume shrinkage (curing shrinkage) caused by the curing reaction of the epoxy resin composition, (2) has the property of suppressing volume change (thermal shrinkage) due to heating of the cured product, that is, has the effect of lowering the coefficient of linear expansion when added, or (3) has both of the above properties. One type of inorganic filler (C) can be used alone, or two or more types can be used in combination.

[0061] Examples of inorganic fillers (C) include silica (silicon dioxide), zeolite, silicon carbide, silicon nitride, alumina (aluminum oxide), aluminum nitride, aluminum hydroxide, aluminum silicate, magnesium silicate, calcium silicate, calcium carbonate, barium sulfate, barium carbonate, titanium oxide, lime sulfate, potassium titanate, magnesium carbonate, zinc oxide, boron nitride, zirconia (zirconium oxide), magnesium zinc pyrophosphate, and materials with treated surfaces. Inorganic fillers (C) can be used individually or in combination of two or more types.

[0062] The inorganic filler (C) is preferably surface-treated with a coupling agent having a functional group such as an epoxy group, a (meth)acryloyl group, or an amino group (especially a phenylamino group). Examples of the coupling agent include silane coupling agents such as 3-glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, and N-phenyl-3-aminopropyltrimethoxysilane. One of the silane coupling agents can be used alone for surface treatment of the inorganic filler (C), or two or more can be used in combination.

[0063] The shape of the inorganic filler (C) is not particularly limited, but examples include spherical (perfectly spherical, nearly spherical, etc.), polyhedral, rod-shaped (cylindrical, prismatic, etc.), plate-shaped, flake-shaped, and irregularly shaped. Among these, a spherical shape is preferred from the viewpoint of achieving a high filling capacity.

[0064] The average particle size of the inorganic filler (C) is not particularly limited, but is preferably 1 nm to 10 μm, more preferably 5 nm to 5 μm, even more preferably 10 nm to 3 μm, and particularly preferably 30 nm to 1 μm. When the average particle size of the inorganic filler (C) is within the above range, the epoxy resin composition tends to have high injectability even in narrow gaps. In addition, two or more fillers with different average particle sizes may be used in combination to adjust the viscosity of the epoxy resin composition. The method for measuring the average particle size of the inorganic filler (C) is not particularly limited, but it can be measured using a laser diffraction / scattering particle size distribution analyzer (product name: LS 13 320, manufactured by Beckman Coulter, Inc.).

[0065] The above epoxy resin composition may contain two or more inorganic fillers with different average particle sizes for the purpose of adjusting viscosity. Specifically, it is preferable to include inorganic filler (C1) with an average particle size of 0.1 to 10 μm and inorganic filler (C2) with an average particle size of 1 nm or more and less than 100 nm as the inorganic filler (C). The average particle size of inorganic filler (C1) is preferably 0.15 to 5 μm, more preferably 0.2 to 3 μm, even more preferably 0.25 to 2 μm, and particularly preferably 0.3 to 1 μm. The average particle size of inorganic filler (C2) is preferably 3 to 80 nm, more preferably 5 to 60 nm, even more preferably 8 to 50 nm, and particularly preferably 10 to 40 nm. When the above epoxy resin composition contains inorganic filler (C1) and inorganic filler (C2), the injectability of the epoxy resin composition is further improved even in narrow gaps, and even better low peelability is exhibited, making it suitable for use as an underfill material.

[0066] Because the epoxy resin composition contains nano-sized inorganic fillers such as inorganic filler (C2), the inorganic fillers in the composition tend not to settle easily. As a result, a sufficient amount of inorganic fillers is present at the interface between the copper pillar and the cured product, which tends to result in better low peelability. In addition, a high storage modulus is exhibited in the temperature range above the glass transition temperature of the cured product, which tends to improve the mechanical strength of the cured product.

[0067] From the viewpoint of reducing the coefficient of thermal expansion (CTE) of the cured product, it is preferable to use a masterbatch of inorganic filler (C) with epoxy resin (A). That is, it is preferable that the epoxy resin composition of the present invention contains part or all of the inorganic filler (C) in the form of a masterbatch with epoxy resin (A). Among inorganic fillers (C), nano-sized inorganic fillers such as inorganic filler (C2) are prone to aggregation within the composition, but it is thought that the occurrence of aggregation can be suppressed by incorporating them in the form of the masterbatch described above, which leads to a reduction in the coefficient of thermal expansion (CTE) of the cured product.

[0068] Examples of commercially available inorganic fillers (C) include "YA050C-SM1", "SE2200-SME", "SE2200-SEJ", "SE1050-SMO", "SE1050-SEO", "SE5200-SEE", "SE101G-SMO", "SE605H-SMG", and "YA010A-JGP" manufactured by Admatex Co., Ltd.

[0069] The content of inorganic filler (C) in the epoxy resin composition (100% by mass) is not particularly limited, but is preferably 30% by mass or more, more preferably 40% by mass or more, even more preferably 45% by mass or more, and particularly preferably 50% by mass or more. Alternatively, it is preferably 90% by mass or less, more preferably 85% by mass or less, even more preferably 80% by mass or less, and particularly preferably 75% by mass or less. When the content of inorganic filler (C) is within the above range, the epoxy resin composition tends to have excellent injectability and improved low peelability.

[0070] The content of the inorganic filler (C1) relative to the epoxy resin composition (100% by mass) is not particularly limited, but is preferably 30% by mass or more, more preferably 40% by mass or more, even more preferably 45% by mass or more, and particularly preferably 50% by mass or more. Alternatively, it is preferably 90% by mass or less, more preferably 85% by mass or less, even more preferably 80% by mass or less, and particularly preferably 75% by mass or less. When the content of the inorganic filler (C1) is within the above range, the epoxy resin composition tends to have excellent injectability and improved low peelability.

[0071] The content of inorganic filler (C) relative to epoxy resin (A) (100% by mass) in the above epoxy resin composition is not particularly limited, but is preferably 60% by mass or more, more preferably 80% by mass or more, even more preferably 100% by mass or more, and particularly preferably 120% by mass or more. Alternatively, it is preferably 600% by mass or less, more preferably 560% by mass or less, even more preferably 520% ​​by mass or less, and particularly preferably 480% by mass or less. When the content of inorganic filler (C) is within the above range, the epoxy resin composition tends to have excellent injectability and improved low peelability.

[0072] The content of inorganic filler (C1) relative to inorganic filler (C) (100% by mass) in the above epoxy resin composition is not particularly limited, but is preferably 60% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, and particularly preferably 97% by mass or more. When the content of inorganic filler (C1) is within the above range, the epoxy resin composition tends to have excellent injectability and improved low peelability.

[0073] The content of inorganic filler (C2) relative to inorganic filler (C) (100% by mass) in the above epoxy resin composition is not particularly limited, but is preferably 0.1% by mass or more, more preferably 0.4% by mass or more, even more preferably 0.8% by mass or more, and particularly preferably 1% by mass or more. Also, is preferably 40% by mass or less, more preferably 30% by mass or less, even more preferably 20% by mass or less, even more preferably 10% by mass or less, even more preferably 5% by mass or less, and particularly preferably 3% by mass or less. When the content of inorganic filler (C2) is within the above range, the epoxy resin composition tends to have excellent injectability and improved low peelability.

[0074] • Coupling agent (D) The epoxy resin composition described above may contain a coupling agent (D). Examples of coupling agents (D) include silane coupling agents such as vinyl, glycidoxy, (meth)acrylic, amino, mercapto, or imidazole; titanium coupling agents such as alkoxide, chelate, or acylate; and long-chain spacer type coupling agents such as glycidoxyoctyltrimethoxysilane or methacrylooctyltrimethoxysilane. One coupling agent (D) may be used alone, or two or more may be used in combination.

[0075] Examples of the silane coupling agents mentioned above include 3-isocyanatetopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 3-methacryloxypropyltrimethoxysilane.

[0076] The content of the coupling agent (D) in the epoxy resin composition (100% by mass) is not particularly limited, but is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, even more preferably 0.15% by mass or more, and particularly preferably 0.2% by mass or more. Also, is preferably 5% by mass or less, more preferably 3% by mass or less, even more preferably 2% by mass or less, and particularly preferably 1% by mass or less.

[0077] Other ingredients (E) The epoxy resin composition described above may contain components other than the epoxy resin (A), curing agent (B), inorganic filler (C), and coupling agent (D) (hereinafter referred to as "other components (E)"). Examples of other components (E) include curable compounds other than epoxy resin (A), core-shell type rubber particles, curing accelerators, latent curing agents, thermoplastic resins such as polyethylene resin, polyester resin, polyurethane resin, polyamide resin, and phenoxy resin, polymer resins having a polyester structure, ion trapping agents, leveling agents, antioxidants, defoaming agents, flame retardants, colorants, reactive diluents, elastomers, silicone compounds, zinc molybdate compounds, cyclic carbodiimides, dispersants (e.g., cationic dispersants), and solvents. Other components (E) can be used individually or in combination of two or more.

[0078] The above-mentioned core-shell type rubber particles are rubber particles composed of a core portion and one or more shell layers covering the core portion. By including the above-mentioned epoxy resin composition with core-shell type rubber particles, crack formation in the cured product can be suppressed. Examples of materials constituting the core portion include silicone-based rubber such as polydimethylsiloxane, butadiene-based rubber, styrene-based rubber, acrylic-based rubber, polyolefin-based rubber, and silicone / acrylic-based composite rubber. Examples of materials constituting the shell layer include monomers having epoxy groups and monomers not having epoxy groups. That is, the shell layer contains monomers having epoxy groups and / or monomers not having epoxy groups as constituent units. Examples of monomers having epoxy groups include glycidyl group-containing (meth)acrylates such as glycidyl (meth)acrylate, glycidyl methyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate glycidyl ether; and glycidyl group-containing vinyl monomers such as allyl glycidyl ether. Examples of monomers that do not have the epoxy group include unsaturated carboxylic acids, (meth)acrylates that do not have an epoxy group, aromatic vinyl compounds, and vinyl cyanide compounds. Examples of unsaturated carboxylic acids include (meth)acrylic acid, itaconic acid, crotonic acid, and maleic anhydride. Examples of (meth)acrylates that do not have an epoxy group include methyl (meth)acrylate, ethyl (meth)acrylate, and butyl (meth)acrylate. 1-5 Examples include alkyl (meth)acrylates. Examples of the above aromatic vinyl compounds include vinylbenzenes such as styrene, α-methylstyrene, p-methylstyrene, and divinylbenzene. Examples of the above vinyl cyanide compounds include acrylonitriles and methacrylonitriles.

[0079] Examples of the curing accelerators mentioned above include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, and 2-phenyl-4-methylimidazole. Specific examples of curing accelerator (F) include 2-phenyl-4-methylimidazole (product name: 2P4MZ) and 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine (product name: 2MZA), both manufactured by Shikoku Chemicals, Inc.

[0080] Silicone compounds (e.g., polycaprolactone-modified dimethyl silicone) are effective in improving the fluidity of compositions. On the other hand, they are undesirable because they tend to reduce the adhesion of compositions and cured products. Cyclic carbodiimides are effective in improving the glass transition temperature of compositions. However, they are undesirable because their reaction is difficult to control, which can compromise the reliability of the cured product. Phenoxy resins (resins with a phenoxy structure) are effective in that they can suppress the occurrence of bleeding. On the other hand, they are undesirable because they tend to reduce the crosslinking density of the cured product, which reduces its toughness and may impair the reliability of the cured product. Cationic dispersants are effective in reducing the formation of aggregates. However, they tend to have poor compatibility with epoxy resins, which is undesirable as it may impair the reliability of the cured product. Polymeric resins with a polyester structure are effective in improving the fluidity of compositions. On the other hand, they are undesirable from the standpoint of low reliability under high temperature and high humidity environments. Latent curing agents (e.g., reaction products of epoxy resin and amine compounds) are effective in terms of curability and heat resistance. On the other hand, they are undesirable because when incorporated into a composition, they tend to increase viscosity and make the cured product brittle, potentially compromising the reliability of the cured product. Zinc molybdate compounds are effective in imparting thermal shock resistance to cured products. However, they have an undesirable tendency to increase the viscosity of the composition, which can lead to reduced injectability. While solvents may be added to the composition, this is undesirable because they may cause voids to form during curing.

[0081] The content of other components (E) relative to the epoxy resin composition (100% by mass) is not particularly limited as long as it does not impair the effects of the present invention, but is preferably 20% by mass or less, more preferably 10% by mass or less, even more preferably 5% by mass or less, and particularly preferably 1% by mass or less. Alternatively, it may be 0.01% by mass or more, 0.1% by mass or more, or 1% by mass or more.

[0082] The solvent content in the epoxy resin composition (100% by mass) is not particularly limited, but is preferably 1% by mass or less, more preferably 0.3% by mass or less, even more preferably 0.1% by mass or less, and particularly preferably 0.01% by mass or less. When the solvent content is within the above range, the low peelability of the epoxy resin composition tends to improve. In other words, when the solvent content in the epoxy resin composition is relatively low, peeling from the copper pillar tends to occur less likely when the cured product is formed. The reasons for this are: (1) the presence of solvent at the interface between the cured product and the copper pillar may reduce the adhesive strength between them; (2) the viscosity of the epoxy resin composition decreases due to the addition of solvent, making it easier for the inorganic filler (C) to settle, resulting in poor low peelability; and (3) since the solvent contained in the epoxy resin composition volatilizes during the curing (heat curing) process, shrinkage stress is generated during curing, making peeling more likely. For these reasons, it is preferable that the solvent content in the epoxy resin composition not be too high.

[0083] The epoxy resin composition described above may or may not contain a styrene-butadiene compound or a PMMA-PnBA block polymer. When the epoxy resin composition contains a styrene-butadiene compound or a PMMA-PnBA block polymer, the coefficient of thermal expansion does not increase easily even at high temperatures, but delamination and cracking tend to occur more easily. Therefore, from the viewpoint of reducing the occurrence of delamination and cracking, it is preferable that the epoxy resin composition does not contain a styrene-butadiene compound or a PMMA-PnBA block polymer. The PMMA-PnBA block polymer is a copolymer of PMMA (polymethyl methacrylate) and PnBA (poly-n-butyl acrylate).

[0084] The epoxy resin composition described above may or may not contain phosphoric acid or polyester phosphate. When the epoxy resin composition contains phosphoric acid or polyester phosphate, the dispersibility of the components in the composition improves, but the strong hydrophilicity of the phosphoric acid group tends to increase the hygroscopicity of the composition and its cured product. Therefore, from the viewpoint of reducing hygroscopicity, it is preferable that the epoxy resin composition does not contain phosphoric acid or polyester phosphate.

[0085] The above epoxy resin composition may contain epoxidized polybutadiene, but it may be omitted because it tends to make it difficult to adjust the storage modulus.

[0086] The viscosity of the epoxy resin composition at 25°C is not particularly limited, but is preferably 1.0 Pa·s or higher, more preferably 2.0 Pa·s or higher, and even more preferably 3.0 Pa·s or higher. Alternatively, it is preferably 200 Pa·s or lower, more preferably 100 Pa·s or lower, even more preferably 50 Pa·s or lower, even more preferably 30 Pa·s or lower, and particularly preferably 20 Pa·s or lower. If the viscosity of the epoxy resin composition at 25°C exceeds 200 Pa·s, it can be measured using a Brookfield HBDV-1 viscometer (using a spindle SC4-14) with the epoxy resin composition at a liquid temperature of 25°C and rotated at 20 rpm for 1 minute. If the viscosity is 200 Pa·s or lower, it can be measured using a Brookfield HBDV-1 viscometer (using a spindle SC4-14) with the epoxy resin composition at a liquid temperature of 25°C and rotated at 50 rpm for 1 minute, as described in the examples below.

[0087] The thixotropic index (TI value) of the epoxy resin composition at 25°C is not particularly limited, but is preferably 0.3 or higher, more preferably 0.5 or higher, and even more preferably 0.6 or higher. Alternatively, it is preferably 2 or lower, more preferably 1.6 or lower, even more preferably 1.3 or lower, and even more preferably 1 or lower. The TI value is calculated as [viscosity at 0.5 rpm] / [viscosity at 5 rpm] and can be measured by the method described in the examples below. Having a TI value within the above range is preferable because it provides appropriate fluidity for the epoxy resin composition during heating. In particular, to make the epoxy resin composition suitable for use as an underfill material, it is preferable to have appropriate thixotropy to improve injectability.

[0088] (Method for manufacturing epoxy resin composition) The epoxy resin composition described above can be prepared by known and conventional methods. For example, the epoxy resin composition can be obtained by simultaneously or separately introducing at least one selected from the group consisting of epoxy resin (A), curing agent (B), inorganic filler (C), and optionally a coupling agent (D) and other components (E) into a suitable mixer, and stirring and mixing while melting by heating as needed. If the epoxy resin (A) is solid, it is preferable to liquefy or fluidize it by heating before mixing. If it is difficult to uniformly disperse the inorganic filler (C) in the epoxy resin composition, the epoxy resin (A) and inorganic filler (C) may be heated and mixed to uniformly disperse the inorganic filler (C) in the epoxy resin (A), then cooled as needed, and further mixing in components such as the curing agent (B) to prepare the epoxy resin composition.

[0089] The above-mentioned mixer is not particularly limited, but examples include a three-roll mill equipped with a stirring device and a heating device, a roll mill, a Leikai mill, a Henschel mixer, a tumbler, a self-rotating mill, a planetary mixer, etc. The mixing ratio of each component is appropriately set according to the content ratio of each component in the epoxy resin composition.

[0090] The above epoxy resin composition can be preferably used as a material (epoxy resin composition for semiconductor encapsulation) for encapsulating materials arranged on a substrate, such as semiconductor elements, wiring, and solder (solder bumps), in semiconductor devices. By using the above epoxy resin composition as an epoxy resin composition for semiconductor encapsulation, highly reliable semiconductor devices can be manufactured. Furthermore, the above epoxy resin composition can be preferably used as a material (epoxy resin composition for flip-chip semiconductor encapsulation) for encapsulating semiconductor elements, etc., arranged on a substrate in flip-chip type semiconductor devices. Specifically, by filling the gap between the semiconductor element, etc., and the substrate with the above epoxy resin composition and applying heat curing, the bumps present in the gap are encapsulated, and the semiconductor element and the substrate are fixed to each other as an encapsulant, thereby improving reliability and reducing the occurrence of bump connection failures.

[0091] The above-mentioned epoxy resin composition for semiconductor encapsulation can be used, for example, as an underfill material such as capillary underfill, liquid mold underfill, secondary underfill, or pre-filled underfill, as well as a grab-top material and a liquid compression mold material. The above-mentioned epoxy resin composition is not limited to its use as an epoxy resin composition for semiconductor encapsulation as described above, and can be used, for example, as an adhesive for fixing, joining, or protecting components that constitute electronic components.

[0092] (Cured epoxy resin composition) A cured product is formed by curing the above epoxy resin composition. The curing method is not particularly limited, but for example, it can be carried out by heat treatment of the epoxy resin composition. The heat treatment temperature is not particularly limited, but for example, 60 to 200°C is preferred, and 80 to 180°C is more preferred. The heat treatment time is not particularly limited, but for example, 0.1 to 5 hours is preferred, and 0.5 to 3 hours is more preferred.

[0093] (Semiconductor device) The semiconductor device of the present invention comprises a substrate, electronic components (e.g., semiconductor elements) provided on the substrate, and a cured product of the epoxy resin composition that encapsulates the electronic components. Preferably, the semiconductor device is a flip-chip type. A flip-chip type semiconductor device has a structure in which the electrode portion on the substrate and the electrode portion of the electronic component are connected via solder bumps. Furthermore, in the semiconductor device, the gap between the electronic component and the substrate is sealed by the cured product (encapsulant) of the epoxy resin composition. The substrate and the electronic component may be connected, for example, via copper pillars and solder (solder bumps). A substrate on which electronic components are provided is referred to as a "primary mounting substrate."

[0094] A semiconductor device (e.g., a primary mounting substrate) can be manufactured by filling the gap between the substrate and the electronic components (e.g., semiconductor elements, etc.) placed on the substrate with the epoxy resin composition (filling step), and then heating and curing the epoxy resin composition (sealing step). The method of filling the gap with the epoxy resin composition is not particularly limited, but for example, by heating the substrate to 50 to 120°C and applying the epoxy resin composition to one end of the substrate or electronic components, the epoxy resin composition is filled into the gap between the substrate and the electronic components by capillary action. After filling the gap with the epoxy resin composition, the gap is sealed by heating the substrate at a predetermined temperature for a predetermined time, specifically at the temperature and time described in the heat treatment for forming the cured product.

[0095] The primary mounting board is generally mounted on a system board (e.g., a motherboard, printed circuit board, etc.). The primary mounting board and the system board may be electrically connected, for example, via solder (solder balls). A primary mounting board mounted on a system board is sometimes referred to as a "secondary mounting board."

[0096] The method for manufacturing a semiconductor device (primary mounting substrate) is not particularly limited, but may include, for example, the following steps. Electronic component connection process: Connecting a copper pillar provided on the surface of an electronic component to the electrode portion of a substrate having an electrode portion by reflow processing. A sealing process in which the epoxy resin composition of the present invention (so-called underfill material) is injected between the above electronic component and the above substrate, and then heat-cured to seal it.

[0097] The electronic component connection process can be described as a process of soldering the copper pillars of electronic components to the substrate by reflow soldering. In this case, the copper pillars and the substrate can be soldered by reflow soldering by (1) providing solder bumps on the tips of the copper pillars of the electronic components, (2) providing solder bumps on the surface of the electrode portion of the substrate, or (3) providing solder bumps on both the tips of the copper pillars of the electronic components and the surface of the electrode portion of the substrate. The reflow soldering process is not particularly limited, but a reflow oven is usually used. The temperature of the reflow soldering process (soldering temperature) is, for example, 180 to 290°C.

[0098] In the sealing process, the heating temperature of the epoxy resin composition is not particularly limited, but is preferably 60 to 200°C, more preferably 80 to 180°C, even more preferably 100 to 175°C, and most preferably 120 to 165°C. The heating time is not particularly limited, but is preferably 0.1 to 5 hours, and more preferably 0.5 to 3 hours.

[0099] The method for manufacturing a semiconductor device (secondary mounting substrate) is not particularly limited, but may include, for example, the following mounting substrate connection step. Furthermore, it may also include the following mounting substrate sealing step. A mounting board connection process in which the electrode portion of the primary mounting board and the electrode portion of the system board are connected by reflow soldering. The mounting board sealing process involves injecting a sealing material between the primary mounting board and the system board, and then heat-curing it to seal the board.

[0100] The mounting board connection process can be described as a process of soldering the primary mounting board and the system board together by reflow soldering. In this case, the primary mounting board and the system board can be soldered together by reflow soldering by (1) providing solder balls on the electrode portion of the primary mounting board, (2) providing solder balls on the surface of the electrode portion of the system board, or (3) providing solder balls on the surfaces of both the electrode portion of the primary mounting board and the electrode portion of the system board. The reflow soldering process is not particularly limited, but a reflow oven is usually used. The temperature of the reflow soldering process (soldering temperature) is, for example, 180 to 290°C.

[0101] In the substrate encapsulation process, the epoxy resin composition of the present invention may be used as the encapsulant. The heating temperature of the encapsulant is not particularly limited, but is preferably 60 to 200°C, and more preferably 80 to 160°C. The heating time is not particularly limited, but is preferably 30 seconds to 5 hours, and more preferably 30 seconds to 3 hours.

[0102] Figures 1(a) to 1(c) are cross-sectional views showing one embodiment of a method for manufacturing a semiconductor device (primary mounting substrate). First, an electronic component 1 having copper pillars 3 is prepared. The copper pillars 3 are provided on the surface of the electronic component 1 and are connected to electrode portions 2. A substrate 6 having electrode portions 5 is also prepared. Solder bumps 4 are formed on the electrode portions 5. The electronic component 1 and the substrate 6 are positioned and aligned so that the copper pillars 3 of the electronic component 1 and the solder bumps 4 on the substrate 6 face each other (Figure 1(a)). Next, the copper pillars 3 and solder bumps 4 are joined and heated (Figure 1(b)). The joining and heating process of the copper pillars 3 and solder bumps 4 is described as a reflow process in primary mounting. Furthermore, an epoxy resin composition 7 is injected into the space (gap) formed between the electronic component 1 and the substrate 6, and heated to cure it into a sealant (cured product) to obtain a primary mounting substrate (Figure 1(c)).

[0103] Figures 2(a) to 2(c) are cross-sectional views showing another embodiment of a method for manufacturing a semiconductor device (primary mounting substrate). First, an electronic component 11 is prepared, having a copper pillar 13 with solder bumps 14 formed at its tip. The copper pillar 13 is provided on the surface of the electronic component 11 and is connected to an electrode portion 12. A substrate 16 having an electrode portion 15 is also prepared. The electronic component 11 and the substrate 16 are positioned and aligned so that the solder bumps 14 of the electronic component 11 and the electrode portions 15 of the substrate 16 face each other (Figure 2(a)). Next, the solder bumps 14 and the electrode portions 15 are joined and heated (Figure 2(b)). The joining and heating process of the solder bumps 14 and the electrode portions 15 is described as a reflow process in primary mounting. Furthermore, an epoxy resin composition 17 is injected into the space (gap) formed between the electronic component 11 and the substrate 16, and heated and cured to form a sealant (cured product), thereby obtaining a primary mounting substrate (Figure 2(c)).

[0104] Figures 3(a) to 3(c) are cross-sectional views showing one embodiment of the manufacturing method for a semiconductor device (secondary mounting substrate) of the present invention. A primary mounting substrate 21 having electrode portions 22 and a system substrate 25 having electrode portions 24 are prepared. Solder balls 23 are provided on the surface of the primary mounting substrate 21 in a manner that connects to the electrode portions 22. However, although not shown, solder balls 23 may also be provided on the surface of the system substrate 25 in a manner that connects to the electrode portions 24. The primary mounting substrate 21 and the system substrate 25 are positioned and aligned so that the solder balls 23 on the primary mounting substrate 21 and the electrode portions 24 on the system substrate 25 face each other (Figure 3(a)). Next, the electrode portions 22 and 24 are joined and heated via the solder balls 23 (Figure 3(b)). The joining and heating process of the electrode portions 22 and 24 with solder balls 23 is described as a reflow process in secondary mounting. Furthermore, a sealing material 26 is injected into the space (gap) formed between the primary mounting substrate 21 and the system substrate 25, and then heat-cured to form a sealing body (cured product), thereby obtaining a secondary mounting substrate (Figure 3(c)).

[0105] The "low peelability" of the epoxy resin composition of the present invention can be described as a characteristic that makes it difficult for the sealant (cured product) on the primary mounting substrate to peel off from the copper pillar during the reflow process in secondary mounting. In the above epoxy resin composition, the difference (°C) between the reflow temperature and the glass transition temperature when manufacturing the secondary mounting substrate is not particularly limited, but it is preferably 100°C or less. In other words, the above epoxy resin composition is preferably used under conditions where the difference (°C) between the reflow temperature and the glass transition temperature is 100°C or less. [Examples]

[0106] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples. Examples 1, 2, and 10 are provided for reference only.

[0107] The epoxy resin compositions of the examples and comparative examples were prepared by appropriately selecting and mixing components such as epoxy resin (A) to achieve the mixing ratios shown in Table 1. The numerical values ​​for each composition in Table 1 represent parts by mass.

[0108] The following is a description of each component in Table 1. • Epoxy resin (A) jER630 (product name): Glycidylamine type epoxy resin (aromatic amine type trifunctional epoxy resin), epoxy equivalent weight 98 g / eq, liquid at 25°C, manufactured by Mitsubishi Chemical Corporation. YDF-8170 (Product Name): Bisphenol F type epoxy resin, epoxy equivalent weight 158 ​​g / eq, liquid at 25°C, manufactured by Nippon Steel Chemical & Material Co., Ltd. HP-4032D (Product Name): Naphthalene-type epoxy resin, epoxy equivalent weight 140 g / eq, liquid at 25°C, manufactured by DIC Corporation. ZX-1658GS (Product Name): 1,4-Glycidylcyclohexane, epoxy equivalent 135 g / eq, liquid at 25°C, manufactured by Nippon Steel Chemical & Material Co., Ltd. • Hardener (B) HD AA: Product name is "KAYAHARD AA", amine-based curing agent, 4,4'-diamino-3,3'-diethyldiphenylmethane, active hydrogen equivalent is 63.5 g / eq, manufactured by Nippon Kayaku Co., Ltd. EtaCure 100plus (product name): Amine-based curing agent, active hydrogen equivalent 44.6 g / eq, diethyltoluenediamine, manufactured by Albemar Co., Ltd. ·Inorganic filler (C) SE2200-SEJ (Product Name): Silica surface-treated with 3-glycidoxypropyltrimethoxysilane, average particle size 0.5 μm, manufactured by Admatex. SE5200-SEE (Product Name): Silica surface-treated with 3-glycidoxypropyltrimethoxysilane, average particle size 1.5 μm, manufactured by Admatex. YA010A-JGP (Product Name): A masterbatch of silica surface-treated with 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane and bisphenol F type epoxy resin (weight ratio: former:latter = 3:7), average silica particle size 10 nm, manufactured by Admatex Co., Ltd. The values ​​in Table 1 represent the mass of silica, and the mass of bisphenol F type epoxy resin is added to YDF-8170. • Coupling agent (D) KBM-403 (Product Name): 3-Glycidoxypropyltrimethoxysilane, manufactured by Shin-Etsu Chemical Co., Ltd. Other ingredients (E) Black 4: Product name is "Special Black 4 powder", carbon black, manufactured by Orion Engineered Carbon. TPP (Product Name): Triphenylphosphine, Thickening Inhibitor, Manufactured by Hokko Chemical Industry Co., Ltd. BCSA: Ethylene glycol mono-n-butyl ether, solvent

[0109] (Evaluation 1: Measurement of glass transition temperature (Tg) and storage modulus at 25°C (GPa)) The epoxy resin compositions of the examples and comparative examples were cured at 165°C for 120 minutes to produce cured products, and the glass transition temperature (Tg) and storage modulus (GPa) at 25°C of the cured products were measured by DMA (Dynamic Mechanical Analysis).

[0110] The glass transition temperature (Tg) is the temperature at which the loss tangent (tanδ) changes with temperature, as measured by the DMA method described above, reaches its peak value (maximum value). The tanδ is obtained by measuring the storage modulus (E') and loss modulus (E'') of the cured material at any given temperature, and then dividing the loss modulus (E'') by the storage modulus (E'). The storage modulus (GPa) is measured according to JIS C6481. The measurement method is described in detail below.

[0111] First, spacers (made of overlapping heat-resistant tape) were placed in two locations on a glass plate coated with a release agent so that the thickness of the cured material would be 2 mm. Next, the epoxy resin composition was applied between the spacers, and the material was sandwiched between another glass plate coated with a release agent to prevent air bubbles from being trapped. The material was then cured at 165°C for 120 minutes to obtain a cured product. After peeling the cured product from the glass plate coated with the release agent, it was cut to a predetermined size (10 mm x 50 mm) using a cutting machine to obtain test specimens. The glass transition temperature (Tg) of these test specimens was measured using a dynamic viscoelasticity measuring device (product name: DMS6100, manufactured by Seiko Instruments Inc.) with a frequency of 1 Hz, strain amplitude of 10 μm, heating rate of 3 °C / min, measurement temperature range of -20 °C to 260 °C, and the double cantilever beam bending method (DCB method). The storage modulus (GPa) at 25 °C was also measured. The results are listed in Table 1 under "Glass transition temperature (°C)" and "Storage modulus at 25°C (GPa)".

[0112] (Evaluation 2: Peel test / Peel rate) An evaluation substrate was obtained by mounting a silicon chip "Walts-TEG FC150JY" with copper pillars onto a substrate "Walts-KIT FC150 01A150P-10" manufactured by Walts Co., Ltd. Measurement samples were prepared by applying and injecting the epoxy resin compositions of the examples and comparative examples onto the evaluation substrate and curing them at 165°C for 120 minutes. These measurement samples were reflowed at 260°C. The reflowed measurement samples were cut along the diagonal, and the cross-sections were observed at 1000x magnification using a scanning electron microscope (SEM) to measure the number of delaminations between the bumps (copper pillars) and the cured epoxy resin composition. The number of delaminations was measured in the same manner, except that the number of reflows was set to 5. Furthermore, the delamination rate (%) was calculated based on the following formula. Delamination rate (%) = Number of delaminations between bumps and hardened material (number of bumps) / Number of bumps observed (number of bumps) The results are recorded in Table 1 under "Peel Test," specifically in the columns for "Peel Rate after 1 Reflow Pass (%)" and "Peel Rate after 5 Reflow Passes (%)." Additionally, Table 1 includes the "Reflow Temperature (°C)" and the "Difference between Reflow Temperature and Glass Transition Temperature (°C)."

[0113] (Evaluation 3: Measurement of viscosity at 25°C) The viscosity (Pa·s) of the epoxy resin compositions of the examples and comparative examples was measured at 25°C. Specifically, a Brookfield HBDV-1 viscometer (using a spindle SC4-14) was used to measure the viscosity of the epoxy resin composition when it was rotated at 50 rpm for 1 minute at a liquid temperature of 25°C. The results are shown in Table 1 under "Viscosity at 25°C (Pa·s)".

[0114] (Evaluation 4: Measurement of TI value) The thixotropic index (TI) values ​​of the epoxy resin compositions in the examples and comparative examples were measured using an E-type viscometer (manufactured by Tokimec Co., Ltd.). The TI value was calculated as [viscosity at 0.5 rpm] / [viscosity at 5 rpm] at 25°C. The results are listed in "TI Value" in Table 1.

[0115] (Rating 5: Coefficient of linear expansion of the cured material CTE) The epoxy resin compositions of the examples and comparative examples were cured at 165°C for 120 minutes to produce cured products, which were then molded into cylindrical shapes with a diameter of 8 mm and a height of 20 mm to create test specimens. The coefficient of linear expansion (CTE) of these test specimens at 0-20°C was measured by thermomechanical analysis (TMA) using a TMA4000SA (Bruker). The length of the test specimen at 0°C and the length of the test specimen at 20°C were measured, and the slope in the range of 0-20°C was defined as the "coefficient of linear expansion CTE at 0-20°C". The results are shown in Table 1 under "CTE at 0-20°C (ppm / °C)".

[0116] [Table 1] [Explanation of Symbols]

[0117] 1 Electronic components 2 Electrode part 3 Copper Pillars 4 solder bumps 5 Electrode part 6 circuit boards 7. Epoxy resin composition 11 Electronic Components 12 Electrode part 13 Copper Pillars 14 solder bumps 15 Electrode part 16 circuit boards 17 Epoxy resin composition 21 Primary mounting board 22 Electrode section 23 Solder balls 24 Electrode section 25 System board 26. Sealing material 31 Copper Pillar 32 Cured product 33 Solder 34 Peeling part

Claims

1. Epoxy resin (A), Hardener (B), and An epoxy resin composition containing an inorganic filler (C), The epoxy resin (A) includes a glycidylamine type epoxy resin. The content of glycidylamine-type epoxy resin relative to epoxy resin (A) (100% by mass) is 32% by mass or more. The curing agent (B) contains an aromatic amine, The inorganic filler (C) includes silica with an average particle size of 0.1 to 3 μm, which may be surface-treated, and silica with an average particle size of 1 nm or more and less than 100 nm, which may be surface-treated. The silica content, relative to epoxy resin (A) (100% by mass), is 60% by mass or more, with an average particle size of 0.1 to 3 μm, and may be surface-treated. The inorganic filler (C) (100% by mass) contains 0.1 to 10% by mass of silica, which may have a surface treatment and an average particle size of 1 nm or more and less than 100 nm. The glass transition temperature of the cured product is 120 to 220°C. The storage modulus of the cured product at 25°C is 6.0 GPa or higher. The solvent content relative to the epoxy resin composition (100% by mass) is 0.1% by mass or less. Free from phosphoric acid, or free from polyester phosphate, It does not contain silicone resins having two or more epoxy groups in one molecule. The thixotropic index (TI) value at 25°C is between 0.3 and 2. Epoxy resin composition.

2. The epoxy resin composition according to claim 1, wherein the coefficient of linear expansion of the cured product at 0 to 20°C is less than 29 ppm / °C.

3. The epoxy resin composition according to claim 1 or 2, wherein the glycidylamine-type epoxy resin has three or more functional groups.

4. The epoxy resin composition according to claim 1 or 2, which does not contain styrene-butadiene compounds and PMMA-PnBA block polymers.

5. The epoxy resin composition according to claim 1 or 2, wherein the viscosity at 25°C is 1.0 to 200 Pa·s.

6. The epoxy resin composition according to claim 1 or 2, wherein, in a peel test under predetermined conditions, the peel rate after five reflow cycles is less than 60%.

7. The epoxy resin composition according to claim 1 or 2, for use in semiconductor encapsulation.

8. The epoxy resin composition according to claim 1 or 2, which is an underfill material.

9. The epoxy resin composition according to claim 1 or 2, further comprising at least one selected from bisphenol-type epoxy resin, cyclohexane-type epoxy resin, and naphthalene-type epoxy resin as the epoxy resin (A).

10. The epoxy resin composition according to claim 1 or 2, wherein the content of epoxy resin having four or more epoxy groups relative to epoxy resin (A) (100% by mass) is 30% by mass or less.

11. The epoxy resin composition according to claim 1 or 2, which does not contain 4,4'-methylenebis(N,N-diglycidylaniline) or 4,4'-[1,4-phenylenebis(dimethylmethylene)]bis(N,N-bisglycidyl-2,6-dimethylaniline).

12. A cured product of the epoxy resin composition according to claim 1 or 2.

13. circuit board and Electronic components arranged on the aforementioned substrate, A cured product according to claim 12 for sealing the electronic component, A semiconductor device equipped with a semiconductor device.

14. A step of filling the gap between the substrate and the electronic components disposed on the substrate with the epoxy resin composition according to claim 1 or 2, A step of heating and curing the epoxy resin composition, A method for manufacturing a semiconductor device containing [a specific component].

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