Epoxy resin composition, cured product, and semiconductor device

Abstract

The present invention provides an epoxy resin composition that is less prone to flow marks. It also provides a cured product of the epoxy resin composition and a semiconductor device comprising the cured product. [Solution] Epoxy resin (A) and, Imidazole compound (C1), An epoxy resin composition comprising an inorganic filler (D), The BET specific surface area of ​​imidazole compounds (C1) is 4.3 to 7.3 m². 2 An epoxy resin composition with a weight of / g.

Description

[Technical Field]

[0001] The present invention relates to epoxy resin compositions, cured products, and semiconductor devices. [Background technology]

[0002] Many semiconductor elements, such as integrated circuits, that make up semiconductor devices are used in a form sealed with an encapsulating material. There are several methods for encapsulating semiconductor elements, one of which is compression molding. Compression molding is a method in which an encapsulating material consisting of liquid, granular, or sheet-like resin is placed in a mold, heated and melted as needed, and compressed to form the product, making it suitable for the manufacture of relatively large molded products. In recent years, the opportunities to adopt compression molding as a method for encapsulating semiconductor elements have been increasing. This is due to the widespread adoption of wafer-level chip-size packaging technology, which has led to the widespread use of processes that encapsulate a large number of semiconductor elements at once in the wafer state. This technology involves performing compression molding using an encapsulating material (compression molding material) at the wafer stage, curing it to encapsulate a large number of semiconductor elements at once, and then separating them into individual pieces.

[0003] Conventional curable resin compositions used for encapsulating semiconductor devices by compression molding have generally been solid (e.g., granular) compositions. However, in recent years, with the development of new compression molding technologies, the use of liquid curable resin compositions has been increasing. Such liquid curable resin compositions are called liquid compression molding (LCM) materials. From the viewpoint of balancing various properties such as electrical properties, moisture resistance, heat resistance, filling ability, fluidity, mechanical properties, and adhesiveness, liquid epoxy resin compositions tend to be used as LCM materials. For example, epoxy resin compositions for semiconductor encapsulation containing imidazole compounds as curing agents (curing catalysts) are known (Patent Documents 1-5). [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2025-119200 [Patent Document 2] Japanese Patent Publication No. 2021-036581 [Patent Document 3] Japanese Patent Publication No. 2022-113053 [Patent Document 4] International Publication No. 2016 / 151717 [Patent Document 5] International Publication No. 2017 / 225599 [Overview of the project] [Problems that the invention aims to solve]

[0005] However, the epoxy resin compositions described in Patent Documents 1 to 5 had a problem in that, when compression molded articles using LCM material were cured, radial patterns would appear on the cured product, known as flow marks. Such flow marks can be said to be one of the causes of a decrease in the appearance quality of the sealant (cured product). The reason why flow marks occur is thought to be that the fluidity of the components in the composition (e.g., resin and inorganic filler) becomes uneven during compression molding, and the resulting differences in the flow history and curing progress rate of the above components are made visible as patterns inside or on the surface of the molded article after curing. Furthermore, although the exact mechanism has not been elucidated, it has been observed that sealants with flow marks are prone to warping and increased thermal expansion (see the examples described below).

[0006] Therefore, an object of the present invention is to provide an epoxy resin composition that is less prone to flow marks. Another object is to provide a cured product of the epoxy resin composition and a semiconductor device equipped with the cured product. [Means for solving the problem]

[0007] As a result of intensive studies to achieve the above object, the present inventors have found that the above problem can be solved by using a composition having a specific configuration. The present invention has been completed based on these findings.

[0008] That is, in the present invention, an epoxy resin (A), an imidazole compound (C1), and an inorganic filler (D), which is an epoxy resin composition, wherein the imidazole compound (C1) has a BET specific surface area of 4.3 to 7.3 m 2 / g, the present invention provides an epoxy resin composition.

[0009] Further, in the present invention, an epoxy resin (A), an imidazole compound (C1), and an inorganic filler (D), which is an epoxy resin composition, the present invention provides an epoxy resin composition, wherein when sieved under specific conditions, less than 20 imidazole particles of 10 µm or more are obtained as a residue.

[0010] Further, in the present invention, an epoxy resin (A), an imidazole compound (C1), and an inorganic filler (D), which is an epoxy resin composition, the present invention provides an epoxy resin composition having a thixotropic index value of less than 1.

[0011] It is preferable that the epoxy resin composition contains, as the epoxy resin (A), at least one selected from the group consisting of bisphenol type epoxy resins, aliphatic epoxy resins, naphthalene type epoxy resins, and glycidylamine type epoxy resins.

[0012] It is preferable that the epoxy resin composition is for semiconductor encapsulation.

[0013] The epoxy resin composition described above is preferably a liquid compression molding material.

[0014] The present invention also provides a cured product of the above epoxy resin composition.

[0015] The present invention also provides a semiconductor device comprising the above-mentioned cured material.

[0016] The present invention also provides a semiconductor device comprising a support, a semiconductor element mounted on the support, and a cured material that seals the gap formed between the support and the semiconductor element.

[0017] Furthermore, the present invention also provides a semiconductor device in which a laminate comprising a support, a semiconductor element mounted on the support, and the cured material that seals the gap formed between the support and the semiconductor element is a compression molded body. [Effects of the Invention]

[0018] The epoxy resin composition of the present invention is less prone to flow marks. Furthermore, semiconductor devices equipped with a cured product of the above epoxy resin composition exhibit high reliability. [Brief explanation of the drawing]

[0019] [Figure 1] This figure illustrates one embodiment of the method for manufacturing a semiconductor device according to the present invention. [Figure 2] This figure illustrates another embodiment of the method for manufacturing a semiconductor device according to the present invention. [Figure 3] This is the appearance of the sealant of Example 1 in Evaluation 7. [Figure 4] This is the appearance of the encapsulant of Comparative Example 1 in Evaluation 7. [Modes for carrying out the invention]

[0020] The first embodiment of the present invention is, Epoxy resin (A) and, Imidazole compound (C1), An epoxy resin composition comprising an inorganic filler (D), The BET specific surface area of ​​imidazole compounds (C1) is 4.3 to 7.3 m². 2 This is an epoxy resin composition with a weight of / g.

[0021] In the first embodiment, the BET specific surface area of ​​the imidazole compound (C1) is 4.3 to 7.3 m². 2 The presence of a specific surface area (BET) of 1 / g suppresses the occurrence of flow marks in the cured product. Although the reason is not entirely clear, it is thought that imidazole compounds (C1) with a BET specific surface area within the above range have a moderately small particle size, which improves the uniformity of the components (resin and inorganic filler) in the composition. As a result, the difference in fluidity between these components is reduced, thereby suppressing the occurrence of flow marks. However, if the BET specific surface area of ​​the imidazole compound (C1) is larger than the above range and the particle size is excessively small, the viscosity of the entire composition increases, which tends to result in poorer packing performance.

[0022] Furthermore, imidazole compounds (i.e., imidazole-based curing accelerators) that are commercially available as curing accelerators are crushed and distributed in a form with an appropriate particle size to improve handling and mixability with other components. Considering the above, the BET specific surface area of ​​commercially available imidazole compounds is 4.3 m². 2 Less than / g (especially 4.2m 2 It is adjusted to be less than / g.

[0023] A second embodiment of the present invention is, Epoxy resin (A) and, Imidazole compound (C1), An epoxy resin composition comprising an inorganic filler (D), This epoxy resin composition contains fewer than 20 imidazole particles larger than 10 μm, obtained as residue when sieved under specific conditions.

[0024] In the second embodiment, "imidazole particles of 10 μm or larger obtained as residue when sieved under specific conditions" refers to imidazole particles of 10 μm or larger that are present as residue on the surface of the sieve (observation range in plan view is 550 μm × 400 μm) when the epoxy resin composition is mixed with a solvent that does not dissolve imidazole, the supernatant is discarded by centrifugation, and this process is repeated five times, followed by filtration through a sieve with a mesh size of 5 μm and drying. The "number of imidazole particles of 10 μm or larger" can be measured more specifically by the method described in the examples below.

[0025] A third embodiment of the present invention is, Epoxy resin (A) and, Imidazole compound (C1), An epoxy resin composition comprising an inorganic filler (D), This is an epoxy resin composition with a thixotropic index value of less than 1.

[0026] In the third embodiment, the occurrence of flow marks in the cured product is suppressed by having an epoxy resin composition with a thixotropic index value of less than 1. Although the reason is not entirely clear, when performing compression molding, the pressure applied to the epoxy resin composition in the void formed by the support and semiconductor element may fluctuate over time due to the operation of the equipment used. On the other hand, from the viewpoint of ensuring uniform fluidity of the components in the composition (e.g., resin and inorganic filler), it is desirable that the viscosity of the composition does not change significantly when filling the void. This is because if the viscosity of the composition fluctuates, the difference in fluidity between the components will increase due to the difference in the shear response of each component contained in the composition. Here, it is considered that a composition with a thixotropic index value of less than 1 exhibits relatively small viscosity changes in response to the applied pressure, and therefore can uniformly fill the void even under conditions of pressure fluctuations.

[0027] In the third embodiment, various means can be considered to make the thixotropic index value of the epoxy resin composition less than 1, for example, (1) adjusting the type and BET specific surface area of ​​the imidazole compound (C1), (2) adjusting the type and content of the epoxy resin (A), (3) adjusting the type and content of the inorganic filler (D), and (4) a combination of (1) to (3).

[0028] Regarding (1), specifically, the imidazole compound (C1) must include at least one selected from the group consisting of 2-phenyl-4-methylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 1-cyanoethyl-2-phenylimidazole, 2-cyanoethyl-4-methylimidazole, 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, and an isocyanuric acid adduct of 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, and the BET specific surface area must be 4.3 to 7.3 m². 2 One example is to set it to / g. Specifically, for (2), the epoxy resin (A) includes at least one selected from the group consisting of bisphenol-type epoxy resin, aliphatic epoxy resin, naphthalene-type epoxy resin, and glycidylamine-type epoxy resin, and its content is within the range described below. For (3), the inorganic filler (D) includes an inorganic filler (D1) with an average particle size of 1 to 20 μm and an inorganic filler (D2) with an average particle size of 1 nm or more and less than 1 μm, and its content is within the range described below.

[0029] • 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 (i.e., a polyfunctional type epoxy resin). Epoxy resin (A) can be used alone or in combination of two or more types.

[0030] 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 handling the epoxy resin composition. Even a solid epoxy resin can be preferably used if it becomes liquid as a mixture when used in combination with a liquid epoxy resin.

[0031] 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, phenol novolac type epoxy resin, tert-butyl-catechol type epoxy resin, naphthalene type epoxy resin, naphthol type epoxy resin (e.g., naphthol novolac type epoxy resin), anthracene type epoxy resin, and Examples include ricidylamine-type epoxy resins, glycidyl ester-type epoxy resins, cresol novolac-type epoxy resins, biphenyl-type epoxy resins, aliphatic epoxy resins (e.g., polyalkylene glycol diglycidyl ether, etc.), aromatic diepoxy compounds (e.g., divinylbenzene dioxide, etc.), epoxy resins having a butadiene structure, alicyclic epoxy resins, heterocyclic epoxy resins, spiroring-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. Note that bisphenol-type epoxy resins also include polyalkylene oxide-modified bisphenol-type epoxy resins.

[0032] From the viewpoint of suppressing flow marks, the epoxy resin (A) preferably contains at least one selected from the group consisting of bisphenol-type epoxy resins such as bisphenol A-type epoxy resin and bisphenol F-type epoxy resin, aliphatic epoxy resin, naphthalene-type epoxy resin, and glycidylamine-type epoxy resin.

[0033] Specific examples of liquid epoxy resins include "YDF-8170" and "YDF-870GS" (both bisphenol F type epoxy resins), "YDF-8125" (bisphenol A type epoxy resin), "ZX-1658" and "ZX-1658GS" (both 1,4-cyclohexanedimethanol diglycidyl ether) from Nippon Steel Chemical & Material Co., Ltd.; "HP-4032," "HP-4032D," and "HP-4032SS" (all naphthalene type epoxy resins) from DIC Corporation; and "jER8" from Mitsubishi Chemical Corporation. "28US", "jER828EL" (both bisphenol A type epoxy resin), "jER806", "jER807" (both bisphenol F type epoxy resin), "jER152" (phenol novolac type epoxy resin), "jER630", "jER630LSD" (both aminophenol type epoxy resin), "YX7400N" (aliphatic epoxy resin / polytetramethylene glycol diglycidyl ether); "Epogosei PT" (polytetramethylene glycol diglycidyl ether) manufactured by Yokkaichi Gosei Co., Ltd. "ZX1059" (a mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin) manufactured by Nippon Steel Chemical & Material Co., Ltd.; "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 a polypropylene glycol structure), "EP-3950L", and "EP-3980S" (both glycidylamine type epoxy resins) manufactured by ADEKA Corporation. ); Asahi Kasei Corporation's "AER9000" (polyalkylene oxide-modified bisphenol-type epoxy resin), "AER4001", "AER4004", and "AER4152" (all oxazolidone ring-containing epoxy resins); Dow Chemical Company's "DER852" and "DER858" (both oxazolidone ring-containing epoxy resins); Nippon Kayaku Co., Ltd.'s "FAE-2500" and "EPPN-501HY" (both trisphenolmethane-type epoxy resins) and "RE-410S" (bisphenol A-type epoxy resin);Examples include "Celoxide 2021P" (alicyclic epoxy resin) manufactured by Daicel Corporation.

[0034] 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.

[0035] The epoxy equivalent of epoxy resin (A) is not particularly limited, but is preferably 30 g / eq or more, more preferably 60 g / eq or more, even more preferably 80 g / eq or more, and especially preferably 90 g / eq or more. Alternatively, it is preferably 600 g / eq or less, more preferably 500 g / eq or less, and even more preferably 450 g / eq or less.

[0036] 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 6% by mass or more, even more preferably 8% by mass or more, even more preferably 10% by mass or more, and particularly preferably 12% by mass or more. Also, is preferably 30% by mass or less, more preferably 24% by mass or less, even more preferably 21% by mass or less, even more preferably 18% by mass or less, and particularly preferably 15% by mass or less. When the content of epoxy resin (A) is within the above range, flow marks tend to be further suppressed.

[0037] • Hardener (B) The epoxy resin composition of the present invention may contain a curing agent (B). The curing agent (B) is not particularly limited, but for example, a phenolic curing agent (B1), an acid anhydride curing agent (B2), and an amine curing agent (B3) are preferred. One type of curing agent (B) may be used alone, or two or more types may be used in combination.

[0038] 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 improving workability in epoxy resin compositions.

[0039] 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 modified acid anhydrides, and examples include phthalic anhydride-based curing agents, succinic anhydride-based curing agents, glutaric anhydride-based curing agents, etc.

[0040] The above-mentioned phthalic anhydride-based curing agent is a curing agent having a skeleton derived from phthalic anhydride. 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 benzophenonetetracarboxylic 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).

[0041] 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.

[0042] The active hydrogen equivalent of the curing agent (B) is not particularly limited, but is preferably 50 g / eq or more, more preferably 80 g / eq or more, even more preferably 100 g / eq or more, and especially preferably 120 g / eq or more. Alternatively, it is preferably 300 g / eq or less, more preferably 240 g / eq or less, even more preferably 180 g / eq or less, and especially preferably 150 g / eq or less.

[0043] The amount of curing agent (B) is not particularly limited, but it is preferably such that the stoichiometric equivalent ratio (active hydrogen equivalent / epoxy group equivalent) with epoxy resin (A) is, for example, 0.5 to 1.5, and more preferably 0.6 to 1.4.

[0044] The content of the curing agent (B) relative to the above epoxy resin composition (100% by mass) is not particularly limited, but is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more. Also, is preferably 40% by mass or less, more preferably 30% by mass or less, and even more preferably 20% by mass or less. When the content of the curing agent (B) is within the above range, the curability of the epoxy resin composition tends to improve.

[0045] In the epoxy resin composition described above, the content of the curing agent (B) relative to the epoxy resin (A) (100% by mass) is not particularly limited, but is preferably 1% by mass or more, more preferably 10% by mass or more, and even more preferably 20% by mass or more. Also, is preferably 50% by mass or less, more preferably 30% by mass or less, and even more preferably 10% by mass or less. When the content of the curing agent (B) is within the above range, the curability of the epoxy resin composition tends to improve.

[0046] • Curing accelerator (C) The curing accelerator (C) has properties that accelerate the curing of the epoxy resin. The epoxy resin composition of the present invention contains an imidazole compound (C1) as the curing accelerator (C), but may further contain at least one selected from the group consisting of a tertiary amine curing accelerator (C2), a phosphorus curing accelerator (C3), and dicyandiamide. The curing accelerator (C) may be used alone or in combination of two or more types.

[0047] Examples of imidazole compounds (C1) include 2-methylimidazole, 2-undecylimidazole, 1,2-dimethylimidazole, 2-heptadecylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 1-cyanoethyl-2-phenylimidazole, 2-cyanoethyl-4-methylimidazole, Examples of imidazole compounds include 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, and isocyanuric acid adducts of 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine.

[0048] Examples of commercially available imidazole compounds (C1) include 2-ethyl-4-methylimidazole (product name: "2E4MZ") manufactured by Shikoku Chemicals Corporation, a mixture of 3-(2-ethyl-4-methyl-1H-imidazol-1-yl)propanenitrile and 3-(2-ethyl-5-methyl-1H-imidazol-1-yl)propanenitrile (product name: "2E4MZ-CN") manufactured by Shikoku Chemicals Corporation, 2-phenyl-4-methylimidazole (product name: "2P4MZ"), 2-phenyl-4-methyl-5-hydroxymethylimidazole (product name: "2P4MHZ-PW"), 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine (product name: "2MZA-PW"), isocyanuric acid adduct of 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine (product name: "2MA-OK"), "2MZ-OK", "2PHZ", and the like. Encapsulated imidazoles called microcapsule-type imidazoles or epoxy adduct-type imidazoles may also be used. Examples of such commercial products include "HX3941HP", "HXA3942HP", "HXA3922HP", "HXA3792", "HX3748", "HX3721", "HX3722", "HX3088", "HX3741", "HX3742", "HX3613" (all manufactured by Asahi Kasei Corporation), "PN-23J", "PN-40J", "PN-50" (manufactured by Ajinomoto Fine-Techno Co., Inc.), "FXR-1121" (manufactured by T&K TOKA Co., Ltd.), and the like.

[0049] The BET specific surface area of the imidazole compound (C1) is not particularly limited, but for example, it is 4.3 to 7.3 m 2 / g, more preferably 4.4 to 7.2 m 2 / g, still more preferably 4.5 to 7 m 2 / g, still more preferably 4.6 to 6.9 m 2 / g, still more preferably 4.7 to 6.8 m 2 / g, still more preferably 4.8 to 6.6 m 2 / g, still more preferably 4.9 to 6.5 m 2 / g, still more preferably 5.0 to 6.3 m 2 / g, more preferably 5.1 to 6.2m 2 The value is / g, and is particularly preferably 5.2 to 6m 2 The value is / g. The BET specific surface area of ​​the imidazole compound (C1) being within the above range tends to further suppress the generation of flow marks. In particular, the lower limit of the BET specific surface area is 4.8 (i.e., the BET specific surface area is 4.8 m²). 2 The occurrence of flow marks tends to be further suppressed by having a concentration of 1 / g or more. The BET specific surface area can be measured by the method described in the examples below.

[0050] Methods for achieving the above-mentioned BET specific surface area of ​​the imidazole compound (C1) include jet milling, roller milling, stone milling, hammer milling, ball milling, and pin milling, with jet milling being the most preferred.

[0051] Examples of tertiary amine-based curing accelerators (C2) include benzyldimethylamine, 2-(dimethylaminomethyl)phenol, 2,4,6-tris(dimethylaminomethyl)phenol, tetramethylguanidine, triethanolamine, N,N'-dimethylpiperazine, triethylenediamine, 1,8-diazabicyclo[5.4.0]undecene, 1,5-diazabicyclo[4.3.0]nonene, and salts thereof. Examples of the salts include formate, octylate, p-toluenesulfonate, o-phthalate, phenol salt, or phenol novolac resin salt of 1,8-diazabicyclo[5.4.0]undecene, and formate, octylate, p-toluenesulfonate, o-phthalate, phenol salt, or phenol novolac resin salt of 1,5-diazabicyclo[4.3.0]nonene.

[0052] Examples of phosphorus-based curing accelerators (C3) include phosphorus compounds such as triphenylphosphine, tri-p-tolylphosphine, tetraphenylphosphonium-tetraphenylborate, triphenylphosphine-triphenylborane, and 1,2-bis-(diphenylphosphine-no)ethane.

[0053] The content of the curing accelerator (C) in the above epoxy resin composition (100% by mass) is not particularly limited, but is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, even more preferably 0.2% by mass or more, even more preferably 0.3% by mass or more, and particularly preferably 0.4% by mass or more. Also, is preferably 5% by mass or less, more preferably 4% by mass or less, even more preferably 3% by mass or less, even more preferably 2% by mass or less, and particularly preferably 1% by mass or less. When the content of the curing accelerator (C) is within the above range, the curability tends to improve.

[0054] The content of the imidazole compound (C1) in the epoxy resin composition (100% by mass) is not particularly limited, but is preferably 0.05% by mass or more, more preferably 0.1% by mass or more, even more preferably 0.2% by mass or more, even more preferably 0.3% by mass or more, and particularly preferably 0.4% by mass or more. Also, is preferably 5% by mass or less, more preferably 4% by mass or less, even more preferably 3% by mass or less, even more preferably 2% by mass or less, and particularly preferably 1% by mass or less. When the content of the imidazole compound (C1) is within the above range, the occurrence of flow marks tends to be further suppressed.

[0055] In the epoxy resin composition described above, the content of the curing accelerator (C) relative to the epoxy resin (A) (100% by mass) is not particularly limited, but is preferably 1% by mass or more, more preferably 1.5% by mass or more, even more preferably 2% by mass or more, even more preferably 2.5% by mass or more, even more preferably 3% by mass or more, and particularly preferably 3.5% by mass or more. Also, is preferably 16% by mass or less, more preferably 12% by mass or less, even more preferably 10% by mass or less, even more preferably 8% by mass or less, even more preferably 6% by mass or less, and particularly preferably 5% by mass or less. When the content of the curing accelerator (C) is within the above range, the curability tends to improve.

[0056] In the epoxy resin composition described above, the content of the imidazole compound (C1) relative to the epoxy resin (A) (100% by mass) is not particularly limited, but is preferably 1% by mass or more, more preferably 1.5% by mass or more, even more preferably 2% by mass or more, even more preferably 2.5% by mass or more, even more preferably 3% by mass or more, and particularly preferably 3.5% by mass or more. Also, is preferably 16% by mass or less, more preferably 12% by mass or less, even more preferably 10% by mass or less, even more preferably 8% by mass or less, even more preferably 6% by mass or less, and particularly preferably 5% by mass or less. When the content of the imidazole compound (C1) is within the above range, the occurrence of flow marks tends to be further suppressed.

[0057] ·Inorganic filler (D) The inorganic filler (D) is not particularly limited, but it is preferable that it has the properties of (1) suppressing volume shrinkage (curing shrinkage) caused by the curing reaction of the epoxy resin composition, (2) suppressing volume change (thermal shrinkage) due to heating of the cured product, that is, having the effect of reducing thermal expansion when added, or (3) having both of these properties.

[0058] Examples of inorganic fillers (D) include silica (silicon dioxide), 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), and materials whose surfaces have been treated (surface-treated materials). From the viewpoint of suppressing the occurrence of flow marks during curing, the epoxy resin composition preferably contains silica (including surface-treated silica, the same applies hereinafter) as the inorganic filler (D). Furthermore, from the viewpoint of thermal conductivity, the epoxy resin composition preferably contains alumina or aluminum nitride (including surface-treated alumina or aluminum nitride, the same applies hereinafter) as the inorganic filler (D). One type of inorganic filler (D) can be used alone, or two or more types can be used in combination.

[0059] The inorganic filler (D) may be 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 coupling agents can be used alone for surface treatment of the inorganic filler (D), or two or more can be used in combination.

[0060] The shape of the inorganic filler (D) 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.

[0061] The average particle size of the inorganic filler (D) is not particularly limited, but is preferably 1 nm to 20 μm, more preferably 5 nm to 16 μm, even more preferably 10 nm to 14 μm, and particularly preferably 30 nm to 12 μm. Because the average particle size of the inorganic filler (D) is within the above range, the particle size is not too large, and the epoxy resin composition tends to have high filling properties even in narrow gaps. Furthermore, two or more fillers with different average particle sizes may be used in combination to adjust the viscosity of the epoxy resin composition. In this specification, the average particle size of the inorganic filler (D) is the volume-based median diameter (D) measured by laser diffraction scattering in accordance with ISO-13320 (2020). 50 This means that the average particle size of the inorganic filler (D) can be measured using a laser diffraction / scattering particle size distribution analyzer.

[0062] In the epoxy resin composition described above, two or more inorganic fillers with different average particle sizes may be used in combination to adjust the viscosity. Specifically, it is preferable that the inorganic filler (D) includes an inorganic filler (D1) with an average particle size of 1 to 20 μm and an inorganic filler (D2) with an average particle size of 1 nm or more and less than 1 μm. The average particle size of inorganic filler (D1) is preferably 2 to 16 μm, more preferably 3 to 14 μm, and even more preferably 4 to 12 μm. The average particle size of inorganic filler (D2) is preferably 10 to 900 nm, and more preferably 100 to 800 nm. When the epoxy resin composition contains inorganic filler (D1) and inorganic filler (D2), the viscosity of the composition is reduced, and there is a tendency for the thermal expansion of the cured product to decrease due to the increased filling ability of the inorganic filler.

[0063] The content of inorganic filler (D) in the epoxy resin composition (100% by mass) is not particularly limited, but is preferably 40% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, even more preferably 75% by mass or more, and particularly preferably 80% by mass or more. Alternatively, it is preferably 92% by mass or less, more preferably 90% by mass or less, even more preferably 88% by mass or less, and particularly preferably 86% by mass or less. When the content of inorganic filler (D) is within the above range, the filling performance tends to improve.

[0064] In the epoxy resin composition described above, the content of inorganic filler (D) relative to epoxy resin (A) (100% by mass) is not particularly limited, but is preferably 320% by mass or more, more preferably 400% by mass or more, even more preferably 480% by mass or more, even more preferably 560% by mass or more, and particularly preferably 640% by mass or more. Alternatively, it is preferably 1000% by mass or less, more preferably 900% by mass or less, even more preferably 800% by mass or less, and particularly preferably 720% by mass or less. When the content of inorganic filler (D) is within the above range, the filling performance tends to improve.

[0065] In the epoxy resin composition described above, the content of inorganic filler (D1) relative to inorganic filler (D) (100% by mass) is not particularly limited, but is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, and particularly preferably 75% by mass or more. Alternatively, it is preferably 95% by mass or less, more preferably 90% by mass or less, even more preferably 86% by mass or less, and particularly preferably 82% by mass or less. When the content of inorganic filler (D1) is within the above range, flow marks tend to be less likely to occur.

[0066] In the epoxy resin composition described above, the content of inorganic filler (D2) relative to inorganic filler (D) (100% by mass) is not particularly limited, but is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 14% by mass or more, and particularly preferably 18% by mass or more. Alternatively, it is preferably 50% by mass or less, more preferably 40% by mass or less, even more preferably 30% by mass or less, and particularly preferably 25% by mass or less. When the content of inorganic filler (D2) is within the above range, flow marks tend to be less likely to occur.

[0067] Other ingredients (E) The epoxy resin composition of the present invention may or may not contain components other than the epoxy resin (A), curing agent (B), curing accelerator (C), and inorganic filler (D) (referred to as "other components (E)"). Examples of other components (E) include curable compounds other than epoxy resin (A), such as (meth)acrylate compounds, maleimide compounds, oxetane compounds, and polysiloxane compounds; thermoplastic resins such as polyethylene resins, polyester resins, polyurethane resins, and polyamide resins; coupling agents; core-shell rubber particles; silicone-based additives; ion trapping agents; leveling agents; antioxidants; defoaming agents; flame retardants; colorants; reactive diluents; elastomers such as alcohol compounds having a polytetramethylene ether structure in the molecule, polyester polyols, silicone compounds, polybutadiene compounds, acrylonitrile-butadiene copolymers, and acrylic block copolymers; solvents; photopolymerization initiators; acid generators; dispersants; and others. Other components (E) may be used individually or in combination of two or more.

[0068] Examples of the coupling agents mentioned above include silane coupling agents such as vinyl, glycidoxy, (meth)acrylic, amino, mercapto, isocyanate, or imidazole; titanium coupling agents such as alkoxide, chelate, or acylate; and various other coupling agents such as long-chain spacer type coupling agents like glycidoxyoctyltrimethoxysilane or methacrylooctyltrimethoxysilane. Examples of the silane coupling agents mentioned above include 3-isocyanatetopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, and 3-mercaptopropyltrimethoxysilane.

[0069] Examples of the above-mentioned silicone-based additives include dialkylpolysiloxanes such as dimethylpolysiloxane. Alternatively, the silicone-based additive may be a modified dialkylpolysiloxane, such as epoxy-modified dimethylpolysiloxane. Specific examples of silicone-based additives include KF69 (dimethyl silicone oil, manufactured by Shin-Etsu Chemical Co., Ltd.) and SF8421 (epoxy-modified silicone oil, manufactured by Toray Dow Silicone).

[0070] Examples of alcohol compounds having a polytetramethylene ether structure within the above molecule include polycarbonate diol compounds having a tetramethylene glycol structure as an alkylene glycol structure, and polytetramethylene ether glycols. Commercially available alcohol compounds of this type include PEPCD NT2006 (a polycarbonate diol compound having a tetramethylene glycol structure as an alkylene glycol structure, liquid (transparent) at 25°C, number average molecular weight 2000, glass transition temperature -84°C, manufactured by Mitsubishi Chemical Corporation), PEPCD NT2002 (a polycarbonate diol compound having a tetramethylene glycol structure as an alkylene glycol structure, liquid (transparent) at 25°C, number average molecular weight 2000, glass transition temperature -71°C, manufactured by Mitsubishi Chemical Corporation), PTMG 2000 (polytetramethylene ether glycol, number average molecular weight 2000, manufactured by Mitsubishi Chemical Corporation), and PTMG 3000 (polytetramethylene ether glycol, number average molecular weight 3000, manufactured by Mitsubishi Chemical Corporation).

[0071] Examples of the above-mentioned dispersants include phosphate ester-based dispersants, alkylammonium salt-based dispersants, alkylolamine salt-based dispersants, and block copolymer-based dispersants. Commercially available dispersants include "DISPER BYK-111" (acid value 129 mgKOH / g), "DISPER BYK-140" (acid value 73 mgKOH / g), "BYK-W9010", "DISPER BYK-163", "DISPER BYK-180" (acid value 94 mgKOH / g), "DISPER BYK-185", "DISPER BYK-1759", "DISPER BYK-2155", and "DISPER BYK-2164" (all manufactured by BYChemie Japan Co., Ltd.).

[0072] The solvent content in the above epoxy resin composition (100% by mass) is, for example, 3% by mass or less, 2% by mass or less, 1% by mass or less, 0.1% by mass or less, or 0.01% by mass or less. Alternatively, it may be, for example, 0.01% by mass or more, 0.1% by mass or more, or 1% by mass or more. Since the solvent volatilizes during the curing of the epoxy resin composition, it may cause void formation in the sealant, so it is preferable that it is not included.

[0073] The content of other components (E) relative to the above epoxy resin composition (100% by mass) is not particularly limited as long as it does not impair the effects of the present invention, but for example it may be 10% by mass or less, 5% by mass or less, 3% by mass or less, or 1% by mass or less. Alternatively, for example it may be 0.01% by mass or more, 0.1% by mass or more, 1% by mass or more, or 3% by mass or more.

[0074] The viscosity of the epoxy resin composition at 25°C is not particularly limited, but is preferably 40 Pa·s or higher, more preferably 80 Pa·s or higher, even more preferably 120 Pa·s or higher, even more preferably 140 Pa·s or higher, and particularly preferably 160 Pa·s or higher. Alternatively, it is preferably 400 Pa·s or lower, more preferably 300 Pa·s or lower, even more preferably 250 Pa·s or lower, and particularly preferably 200 Pa·s or lower. The viscosity of the epoxy resin composition at 25°C 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 10 rpm for 1 minute, as described in the examples below.

[0075] The thixotropic index (TI value) of the epoxy resin composition at 25°C is not particularly limited, but is preferably 0.6 or higher, more preferably 0.7 or higher, even more preferably 0.8 or higher, and particularly preferably 0.85 or higher. Also, for example, it is preferably less than 1, more preferably 0.96 or lower, even more preferably 0.92 or lower, and particularly preferably 0.9 or lower. The above TI value is calculated as [viscosity at 1 rpm] / [viscosity at 10 rpm] and can be measured by the method described in the examples below.

[0076] The gel time of the epoxy resin composition at 150°C is not particularly limited, but is preferably 60 seconds or more, more preferably 80 seconds or more, even more preferably 100 seconds or more, and especially preferably 120 seconds or more. Alternatively, it is preferably 300 seconds or less, more preferably 240 seconds or less, even more preferably 210 seconds or less, even more preferably 180 seconds or less, and especially preferably 150 seconds or less. The gel time can be measured by the method described in the examples below.

[0077] (Method for manufacturing epoxy resin composition) The epoxy resin composition described above can be prepared by known and conventional methods. For example, at least one selected from the group consisting of epoxy resin (A), curing agent (B), curing accelerator (C), inorganic filler (D), and other components (E) can be introduced simultaneously or separately into a suitable mixer and stirred and mixed while melting by heating as needed to obtain the epoxy resin composition. 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 (D) in the epoxy resin composition, the epoxy resin (A) and inorganic filler (D) may be heated and mixed to uniformly disperse the inorganic filler (D) in the epoxy resin (A), then cooled as needed, and further mixed with components such as the curing agent (B) to prepare the epoxy resin composition.

[0078] 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.

[0079] The above epoxy resin composition can be preferably used as a material (epoxy resin composition for semiconductor encapsulation) for encapsulating materials mounted on a support such as semiconductor elements, wiring, and solder (solder bumps) in a semiconductor device. By using the above epoxy resin composition as an epoxy resin composition for semiconductor encapsulation, a highly reliable encapsulated body 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 mounted on a support in a flip-chip type semiconductor device. Specifically, by filling the gap between the semiconductor element and the support with the above epoxy resin composition and curing it, the bumps present in the gap can be encapsulated while fixing the semiconductor element and the support to each other as an encapsulated body, thereby improving thermal cycle resistance.

[0080] The epoxy resin composition described above may be liquid or solid at room temperature (25°C). Furthermore, the epoxy resin composition can be used, for example, as an underfill such as capillary underfill, liquid mold underfill, secondary underfill, or pre-filled underfill, as well as a grab-top material and a liquid compression molding material. Moreover, the epoxy resin composition is not limited to its use as an epoxy resin composition for semiconductor encapsulation as described above; it can also be used, for example, as an adhesive for fixing, joining, or protecting components that constitute electronic components. In this specification, the liquid compression molding material may be a compression molding material supplied to a material such as a semiconductor element and a support, and filled into the gap between the material and the support, thereby sealing the gap between the material and the support by curing. Alternatively, it may be a compression molding material (for overmolding or grab-top applications) intended to seal the outer periphery of a material such as a semiconductor element, without the purpose of filling a gap.

[0081] (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.

[0082] The storage modulus (GPa) at 25°C of the cured product obtained by curing the above epoxy resin composition at 150°C for 120 minutes is not particularly limited, but is preferably 3 GPa or higher, more preferably 6 GPa or higher, even more preferably 9 GPa or higher, and particularly preferably 12 GPa or higher. Alternatively, it is preferably 24 GPa or lower, more preferably 21 GPa or lower, even more preferably 18 GPa or lower, and particularly preferably 15 GPa or lower. When the storage modulus is within the above range, the occurrence of cracks tends to be reduced. The storage modulus (GPa) can be measured by the method described in the examples below.

[0083] The coefficient of linear expansion (CTE1) (ppm / °C) of the cured product obtained by curing the above epoxy resin composition at 150°C for 120 minutes is not particularly limited, but is preferably 0 ppm / °C or higher, more preferably 3 ppm / °C or higher, and even more preferably 6 ppm / °C or higher. Also, is preferably 30 ppm / °C or lower, more preferably 15 ppm / °C or lower, even more preferably 10 ppm / °C or lower, and particularly preferably 8 ppm / °C or lower. When the coefficient of linear expansion is within the above range, the occurrence of cracks caused by temperature changes tends to be reduced. The coefficient of linear expansion can be measured by the method described in the examples below.

[0084] The coefficient of linear expansion (CTE2) (ppm / °C) of the cured product obtained by curing the above epoxy resin composition at 150°C for 120 minutes is not particularly limited, but is preferably -10 ppm / °C or higher, more preferably 0 ppm / °C or higher, even more preferably 10 ppm / °C or higher, and particularly preferably 15 ppm / °C or higher. Alternatively, it is preferably 50 ppm / °C or lower, more preferably 30 ppm / °C or lower, and even more preferably 20 ppm / °C or lower. When the coefficient of linear expansion is within the above range, the occurrence of cracks caused by temperature changes tends to be reduced. The coefficient of linear expansion can be measured by the method described in the examples below.

[0085] <Semiconductor device and method for manufacturing the same> The semiconductor device of the present invention comprises a support, a semiconductor element mounted on the support, and a cured product of the epoxy resin composition that seals the semiconductor element. The semiconductor device may be a flip-chip type semiconductor device. The flip-chip type semiconductor device has a structure in which an electrode portion on the support and the semiconductor element are connected via bump electrodes. In addition, the gap formed between the support and the semiconductor element of the semiconductor device is sealed by the cured product of the epoxy resin composition. That is, the semiconductor device comprises a support, a semiconductor element mounted on the support, and the cured product that seals the gap formed between the support and the semiconductor element. The width of the gap is not particularly limited, but for example, it is 40 μm or less, preferably 30 μm or less, more preferably 20 μm or less, even more preferably 10 μm or less, and particularly preferably 5 μm or less.

[0086] The method for manufacturing a semiconductor device of the present invention is: A step of supplying the epoxy resin composition onto a laminate comprising a support and a semiconductor element mounted on the support (hereinafter referred to as the "composition supply step"), The process involves filling the gap between the support and the semiconductor element with the epoxy resin composition to form a molded body, curing the molded body to seal the semiconductor element, and obtaining a sealed body (hereinafter referred to as the "molding and sealing process"), It is characterized by including.

[0087] The semiconductor device manufacturing method of the present invention may further include a step of polishing the above-mentioned encapsulant (hereinafter referred to as the "grinding step"). It may also include at least one selected from the group consisting of the laminate preparation step and the individualization step described later.

[0088] (Laminate preparation process) The laminate preparation step is a step of preparing a laminate comprising a support and semiconductor elements mounted on the support by mounting semiconductor elements on the support. In the laminate, the support and the semiconductor elements may be connected via solder, or they may be connected using adhesive films such as die attach films (DAF) or adhesive sheets. The support is not particularly limited, but examples include silicon wafers, silicon carbide wafers, sapphire wafers, compound semiconductor wafers (gallium phosphide, gallium arsenide, indium phosphide, gallium nitride), glass epoxy substrates, organic substrates (FR4 substrates), etc. The shape of the support in plan view is not particularly limited, but for example it may be circular or rectangular.

[0089] (Composition supply process) The composition supply step is a step of supplying the epoxy resin composition onto a laminate comprising a support and a semiconductor element mounted on the support.

[0090] This process may include a step of attaching a mold used to form a molded body in the molding and sealing process to the laminate. That is, the composition supply step may be a step of supplying an epoxy resin composition onto a laminate comprising a support and a semiconductor element mounted on the support, and then attaching a mold to the laminate.

[0091] Furthermore, this process may also involve supplying an epoxy resin composition to a mold used for forming a molded body in the molding and sealing process, and then mounting a laminate comprising a support and a semiconductor element mounted on the support into the mold. By performing such a process, the epoxy resin composition can be supplied onto the laminate comprising the support and the semiconductor element mounted on the support.

[0092] (Molding / sealing process) The molding and sealing process involves filling the gap between the support and the semiconductor element with the epoxy resin composition to form a molded body, curing the molded body to seal the semiconductor element, and obtaining a sealed body. This process may include two steps: filling the gap between the support and the semiconductor element with the epoxy resin composition to form a molded body (molding process), and curing the molded body obtained in the molding process to seal the semiconductor element and obtain a sealed body (sealing process). The width of the gap is not particularly limited, but is, for example, 40 μm or less, preferably 30 μm or less, more preferably 20 μm or less, even more preferably 10 μm or less, and especially preferably 5 μm or less.

[0093] The method for forming the molded body is not particularly limited, but for example, one method involves pushing a mold attached to the laminate in the direction of the laminate (support), and, if necessary, reducing the pressure inside the mold to fill the gap between the support and the semiconductor element with the epoxy resin composition, thereby forming a compression molded body containing the laminate and the epoxy resin composition. In this step, instead of pushing the mold in the direction of the laminate (support), the laminate (support) may be pushed in the direction of the mold, or a configuration in which the mold and the laminate (support) are squeezed together may be adopted.

[0094] One method for forming a molded body is to use a molding apparatus to reduce the viscosity of an epoxy resin composition by heating as needed, and then reduce the pressure of the epoxy resin composition to seal the laminate. A molded body can be obtained by this forming method.

[0095] When curing the above molded body to seal the semiconductor element, the curing of the epoxy resin composition may be carried out by heating. The curing temperature is not particularly limited, but is preferably 100 to 180°C, more preferably 110 to 150°C, and even more preferably 115 to 130°C. The curing time is not particularly limited, but is preferably 30 minutes to 7 hours, more preferably 1 to 6 hours, even more preferably 1 to 4 hours, and especially preferably 1 to 2 hours. The pressure during sealing is not particularly limited, but is preferably 50 to 500 kN, more preferably 200 to 300 kN.

[0096] (Grinding process) The grinding process is a process of polishing the encapsulated body obtained by the molding and encapsulation process. More specifically, it is a process of grinding the surface of the encapsulated body on the semiconductor element side in order to flatten and thin the encapsulated body, and to expose a part of the semiconductor element as needed. The method of grinding is not particularly limited, and commercially available grinding wheels and grinding equipment can be used.

[0097] (Singulation process) The individualization step is a process of separating the sealed body obtained by the molding and sealing step, or the sealed body ground by the grinding step, into individual pieces. The individualization step may also be a process of separating the sealed body after removing it from the mold. In the individualization step, the gaps between multiple semiconductor elements mounted on the support and sealed with a cured epoxy resin composition are cut using means such as a dicing blade or a laser to obtain a semiconductor device. The method of individualization is not particularly limited, and commercially available individualization devices can be used.

[0098] The following describes embodiments of a semiconductor device manufacturing method using Figures 1 and 2, but the present invention is not limited thereto.

[0099] Figure 1 shows one embodiment of the method for manufacturing a semiconductor device according to the present invention. This embodiment will be described below with reference to Figure 1. A semiconductor element 1, having solder bumps 2 on one side, is mounted on a support 3, and a laminate 4 is prepared containing the semiconductor element 1, solder bumps 2, and support 3 in this order (laminated body preparation step, (a)). An epoxy resin composition 5 is supplied onto the semiconductor element 1 of the laminate 4 using a syringe 6, and then a mold 7 is attached (composition supply step, (b) and (c)). In this step, a release film may be provided on the surface of the mold 7 that is oriented toward the laminate 4. The release film is positioned so that the mold 7 and the epoxy resin composition 5 do not come into contact, and also to facilitate the removal of the sealant 9 from the mold 7 in step (f) described later. The release film is not shown in the figure. Next, the attached mold 7 is pushed toward the support 3, and the pressure inside the mold 7 is reduced as needed to form a compression molded body 8 containing the laminate 4 and epoxy resin composition 5 (molding step, (d)). In this step, instead of pushing the mold 7 in the direction of the support 3, the support 3 may be pushed in the direction of the mold 7, or a method may be adopted in which the mold 7 and the support 3 are narrowed relative to each other. In this step, the epoxy resin composition 5 is filled into the gap between the support 3 and the semiconductor element 1 to form a compression molded body 8. The compression molded body 8 is heat-cured to seal the semiconductor element 1 and form a sealant 9 (sealing step, (e)). After removing the mold 7, the sealant 9 containing the semiconductor element 1 is separated into individual pieces (separation steps, (f) and (g)).

[0100] Figure 2 shows another embodiment of the semiconductor device manufacturing method of the present invention. This embodiment will be described below with reference to Figure 2. A semiconductor element 11, having solder bumps 12 on one side, is mounted on a support 13, and a laminate 14 is prepared containing the semiconductor element 11, solder bumps 12, and support 13 in this order (laminated laminate preparation step, (a)). After supplying the epoxy resin composition 15 to the mold 17 using a syringe 16, the laminate 14 is mounted in the mold (composition supply step, (b) and (c)). In this step, a release film may be provided on the supply surface of the epoxy resin composition 15 in the mold 17. That is, in this step, (1) the epoxy resin composition 15 may be supplied to the surface of the mold 17 that has the release film, or (2) the epoxy resin composition 15 may be supplied onto the release film, and then the release film may be placed in the mold 17. The release film is positioned so that the mold 17 and the epoxy resin composition 15 do not come into contact, and also to facilitate the removal of the sealant 19 from the mold 17 in step (f) described later. The release film is not shown in the figure. Next, the inside of the mold 17 is depressurized to form a compression molded body 18 containing the laminate 14 and the epoxy resin composition 15 (molding step, (d)). In this step, the epoxy resin composition 15 is filled into the gap between the support 13 and the semiconductor element 11, forming the compression molded body 18. The compression molded body 18 is heat-cured to seal the semiconductor element 11, forming a sealant 19 (sealing step, (e)). After removing the mold 17, the sealant 19 containing the semiconductor element is separated into individual pieces (separation steps, (f) and (g)). [Examples]

[0101] The present invention will be described in more detail below based on examples, but the present invention is not limited to these examples.

[0102] [Manufacturing Example 1] 2MZA-PW(2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine), manufactured by Shikoku Chemicals Co., Ltd., has a BET specific surface area of ​​3.11 m². 2The compound ( / g) was ground at a pressure of 0.55 MPa using a jet mill (product name: Single Track Jet Mill (Horizontal Jet Crusher), model number: FS-4, manufactured by Seishin Corporation) to obtain imidazole compound 1. The BET specific surface area of ​​imidazole compound 1 was 5.75 m². 2 It was / g.

[0103] 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. In Comparative Example 1, the epoxy resin composition was prepared by first dispersing and mixing the imidazole compound in the epoxy resin using a roll mill, and then further mixing it with other components using a planetary mixer. This preparation operation is referred to as "pre-dispersion" in Table 1. The numerical values ​​for each component in the table represent parts by mass.

[0104] The following is a description of each component in Table 1. [Epoxy resin (A)] jER630 (product name): Glycidylamine type epoxy resin, epoxy equivalent weight 98 g / eq, liquid at 25°C, manufactured by Shin-A T&C Co., Ltd. YX7400N (Product Name): Aliphatic epoxy resin (polytetramethylene glycol diglycidyl ether), epoxy equivalent weight 420 g / eq, liquid at 25°C, manufactured by Mitsubishi Chemical Corporation. YDF-8170 (Product Name): Bisphenol-type F epoxy resin, epoxy equivalent weight 156-162 g / eq, liquid at 25°C, manufactured by Nippon Steel Chemical & Material Co., Ltd. RE-410S (Product Name): Bisphenol A type epoxy resin, epoxy equivalent 178 g / eq, manufactured by Nippon Kayaku Co., Ltd. [Curing accelerator (C)] Imidazole compound 1: 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine obtained by Preparation Example 1, with a BET specific surface area of ​​5.75 m². 2 / g 2MZA-PW (product name): 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, BET specific surface area is 3.11 m². 2 / g, manufactured by Shikoku Chemicals Co., Ltd. [Inorganic filler (D)] Inorganic filler 1: Silica filler (untreated surface), average particle size 0.6 μm Inorganic filler 2: Silica filler (untreated surface), average particle size 10.0 μm [Other ingredients (E)] Black 4: Product name is Special Black 4, Carbon Black, manufactured by Orion Engineered Carbons Co., Ltd. KBE-9007N (Product Name): 3-Isocyanate-propyltriethoxysilane, isocyanate-based silane coupling agent, manufactured by Shin-Etsu Chemical Co., Ltd.

[0105] <Evaluation 1: Viscosity measurement of epoxy resin composition> The viscosity (Pa·s) of the epoxy resin compositions of the examples and comparative examples at 25°C was measured using a Brookfield HBDV-1 viscometer (using a SC4-14 spindle) at a liquid temperature of 25°C, rotated at 10 rpm for 1 minute. The results are shown in Table 1, under "Viscosity at 25°C (Pa·s)".

[0106] <Evaluation 2: Measurement and calculation of TI value> After the viscosity measurement in Evaluation 1, the sample was allowed to stand for 10 minutes, and then the viscosity was measured again after rotating at 1 rpm for 1 minute. The thixotropic index (TI) value was calculated as [viscosity at 1 rpm] / [viscosity at 10 rpm] at 25°C. The results are listed in "25°C TI value" in Table 1.

[0107] <Evaluation 3: Measurement of gel time> Using the "Madoka" automatic curing time measuring device and stirring rod (model number: 5TC-72890) manufactured by Matsuo Sangyo Co., Ltd., the epoxy resin compositions (0.3 ml ± 0.1 ml) of the examples and comparative examples were placed on a stainless steel plate heated to 150°C. Immediately after placement, stirring was performed with biaxial eccentricity (rotation speed 120 rpm, revolution speed 50 rpm), and the time from placement to gelation (gel time) was measured. The gelation point was defined as the point when the torque judgment value reached 30%. The results are listed in "Gel Time (seconds)" in Table 1.

[0108] <Evaluation 4: Measurement of the coefficient of linear expansion (CTE)> The epoxy resin compositions of the examples and comparative examples were cured at 150°C for 120 minutes to produce cured products, and test specimens were prepared by molding them into cylindrical shapes with a diameter of 8 mm and a height of 20 mm. The coefficient of linear expansion (CTE1) at 0-40°C and the coefficient of linear expansion (CTE2) at 170-200°C of these test specimens were measured by thermomechanical analysis (TMA) using a TMA4000SA (Bruker). The length of the test specimens was measured at 0°C, 40°C, 170°C, and 200°C, respectively. The slope in the 0-40°C range was defined as "Coefficient of linear expansion (CTE1) at 0-40°C," and the slope in the 170-200°C range was defined as "Coefficient of linear expansion (CTE2) at 170-200°C." The results are listed in Table 1 as "CTE1 (ppm / °C)" and "CTE2 (ppm / °C)."

[0109] <Rating 5: Storage Modulus> The storage modulus of the cured epoxy resin compositions of the examples and comparative examples was measured using a dynamic viscoelastic device. The measurements were performed in accordance with Japanese Industrial Standard JIS C6481.

[0110] Specifically, first, a release agent was applied to the surface of a 3 mm thick glass plate, and spacers (layered heat-resistant tape) were placed in two locations on top of it so that the film thickness of the cured material was 2000 ± 100 μm. Next, an epoxy resin composition was applied between the spacers, and to prevent air bubbles from being trapped, it was sandwiched between another glass plate with a Teflon® sheet attached to its surface, and cured at 150°C for 120 minutes to obtain a cured material. Finally, after peeling this cured material from the glass plate with the Teflon® sheet attached, it was cut to the specified dimensions (10 mm × 50 mm) using a cutting machine to obtain a sample. The storage modulus (GPa) at 25°C was measured using a dynamic thermomechanical analyzer (DMA) (DMA7100, manufactured by Hitachi High-Tech Science Corporation) in the range of -60°C to 260°C, at a frequency of 1 Hz, a heating rate of 3°C / min, and the double-arm bending method. The results are listed in "Storage Modulus (GPa) at 25°C" in Table 1.

[0111] <Rating 6: Warp Rating> The following experiment was conducted using the "WCM-300" product manufactured by Apic Yamada Co., Ltd. as the molding device. The epoxy resin compositions of the examples and comparative examples were applied to the surface of a circular wafer (12-inch silicon wafer, dummy grade, notched type, manufactured by SUMCO Corporation) with a diameter of 299.4 mm and a thickness of 775 μm, so that the wafer had a diameter of 292.0 mm and a thickness of 500 μm. The wafer was adjusted so that the center of the applied epoxy resin composition coincided with the center of the wafer. A wafer coated with an epoxy resin composition was placed in the mold on the lower side of the molding device. A release film (product name: TBM, manufactured by TOWA Corporation) was placed in the upper mold of the molding apparatus, and the wafer was compressed and depressurized by the upper and lower molds to form a compression molded body. Furthermore, the compression molded body was thermocured to prepare an evaluation sample. These operations were performed under the following conditions: mold temperature of 120°C, mold cure time of 400 seconds, clamping force of 250kN, and PMC (Post Mold Cure) of 150°C / 1hr. The resulting sealant was used to measure the warpage at 25°C using a shadow moiré apparatus (Akrometrix, AXP 2.0-DFP2). The highest point was recorded as the warpage when the sealant was placed on a horizontal table with the cured surface facing upwards. If the highest point was at the center of the sealant, the warpage was recorded as negative; if the highest point was at the outer edge, the warpage was recorded as positive. The measured warpage (μm) values ​​are shown in Table 1 under "Warpage (μm)".

[0112] <Rating 7: Flowmark Rating> The encapsulants obtained in Evaluation 6 were visually evaluated for their appearance. Those without flow marks were marked with "○", and those with flow marks were marked with "×". The results are shown in Table 1 under "Flow Mark Evaluation".

[0113] [Table 1]

[0114] As described above, flow marks were observed in Comparative Examples 1 and 2, but not in Example 1. Even when other imidazole compounds were used instead of 2MZA-PW, the BET specific surface area was 4.3 to 7.3 m². 2 By using / g, we confirmed that no flow marks were observed.

[0115] <Evaluation 8: Number of imidazole particles larger than 10 μm> In a 10 ml test tube for a glass centrifuge, 1 g of the epoxy resin composition of the example and comparative example and 9 g of chloroform were placed and stirred with a spatula at a rate of 1 rotation / second for 1 minute. The resulting mixture was centrifuged for 5 minutes at a rotation speed of 2500 rpm using a C-12B centrifuge manufactured by AS ONE Corporation. The supernatant after treatment was discarded, and another 9 g of chloroform was added and stirred with a spatula at a rate of 1 rotation / second for 1 minute. This mixture was then centrifuged again for 5 minutes using the same centrifuge under the same conditions as above, and the supernatant was discarded. This process was repeated a total of 5 times. After discarding the supernatant for the 5th time, 9 g of chloroform was added and mixed under the same conditions as above, and the mixture was filtered using a 5 μm nylon mesh NY5-HC manufactured by SEFER, and the residue was allowed to air dry.

[0116] Using a Keyence YHX7000 digital microscope, the surface of a nylon mesh was observed at 500x magnification (field of view: 550 μm × 400 μm), and residues larger than 10 μm were picked up from the mesh. The picked-up residues were analyzed using a PerkinElmer FT-IR Spotlight 400 to determine whether or not they were imidazole. Based on the above, the number of imidazole particles with a maximum length of 10 μm or more within the field of view was measured. The same process was performed 10 times, and the average value was taken as the "number of imidazole particles larger than 10 μm". Note that the maximum length refers to the longest length of the line segment connecting any two points on the contour of the particle when viewed from above. In the epoxy resin composition of the example, the number of imidazole particles larger than 10 μm was 8. On the other hand, in the epoxy resin compositions of Comparative Examples 1 and 2, the number of imidazole particles larger than 10 μm was 33 and 54, respectively. [Explanation of Symbols]

[0117] 1. Semiconductor element 2 solder bumps 3 Support 4 Laminate 5. Epoxy resin composition 6 Syringes 7 molds 8 Compression molded body 9 Sealing body 11 Semiconductor devices 12 solder bumps 13 Support 14 Laminate 15 Epoxy resin composition 16 Syringes 17 molds 18 Compression molded body 19 Sealing body

Claims

1. Epoxy resin (A) and Imidazole compound (C1), An epoxy resin composition comprising an inorganic filler (D), Epoxy resin (A) is a liquid epoxy resin, The imidazole compound (C1) is 2-methylimidazole, 2-undecylimidazole, 1,2-dimethylimidazole, 2-heptadecylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 1-cyanoethyl-2-phenylimidazole, 2-cyanoethyl-4-methylimidazole, 2,4-dia At least one selected from the group consisting of mino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, and isocyanuric acid adducts of 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, The BET specific surface area of ​​imidazole compounds (C1) is 4.3 to 7.3 m². ２ / g, The epoxy resin (A) content is 4 to 30% by mass. The imidazole compound (C1) content is 0.05 to 5% by mass. An epoxy resin composition having an inorganic filler (D) content of 40 to 92% by mass.

2. The epoxy resin composition according to claim 1, wherein the gel time at 150°C is 60 to 300 seconds.

3. The epoxy resin composition according to claim 1 or 2, wherein the thixotropic index value at 25°C is less than 1.

4. The epoxy resin composition according to claim 1 or 2, wherein the epoxy resin (A) comprises at least one selected from the group consisting of bisphenol-type epoxy resin, polyalkylene glycol diglycidyl ether, naphthalene-type epoxy resin, and glycidylamine-type epoxy resin.

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

6. The epoxy resin composition according to claim 1 or 2, which is a liquid compression molding material.

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

8. A semiconductor device comprising the cured product described in claim 7.

9. A semiconductor device comprising a support, a semiconductor element mounted on the support, and a cured product according to claim 7 for sealing the gap formed by the support and the semiconductor element.

10. The semiconductor device according to claim 9, wherein the laminate comprising a support, a semiconductor element mounted on the support, and a cured material that seals the gap formed by the support and the semiconductor element is a compression molded body.

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