Resin composition for sealing and semiconductor device

Abstract

To provide a resin composition for sealing from which a semiconductor device excellent in product reliability can be obtained.SOLUTION: A resin composition for sealing contains an inorganic filler (A), an epoxy resin (B), and a low stress material (C), wherein a cured product obtained by curing the resin composition for sealing at 175°C for 4 hours has a flexural modulus at 25°C of 5,000 N / mm2 or more and 15,000 N / mm2 or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an encapsulating resin composition and a semiconductor device. [Background technology]

[0002] In recent years, with the advancement of high performance and high speed of heat-generating electronic components such as ICs, the amount of heat generated by electronic devices incorporating these components has increased, and high heat dissipation properties are also required for semiconductor encapsulation materials. In order to improve the thermal conductivity of encapsulation materials made from encapsulating resin compositions, it is common to increase the amount of inorganic filler added.

[0003] However, as the amount of inorganic filler increases, the linear expansion coefficient of the encapsulant decreases, which increases the difference in linear expansion coefficient between components that make up the semiconductor device, such as the substrate and encapsulant, and can reduce the product reliability of the semiconductor device. Patent Document 1 discloses a resin composition for semiconductor encapsulation, which contains an epoxy resin, a curing agent, and an inorganic filler containing calcium fluoride. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2017-088828 [Patent Document 2] Patent Publication No. 2021-91878 [Patent Document 3] Japanese Patent Publication No. 2022-55335 Summary of the Invention [Problem to be solved by the invention]

[0005] However, even with the technology described in Patent Document 1, there is still room for improvement in the product reliability of the semiconductor device. [Means for solving the problem]

[0006] The present inventors have discovered that, when the flexural modulus of a cured product obtained from an encapsulating resin composition is within a predetermined range, the product reliability of a semiconductor device in which a semiconductor element is encapsulated with an encapsulant obtained from the composition is improved, and have completed the present invention. That is, the present invention can be shown as follows.

[0007] [1] An encapsulating resin composition comprising an inorganic filler (A), an epoxy resin (B), and a low-stress material (C), The encapsulating resin composition was cured at 175°C for 4 hours, and the cured product had a flexural modulus of 5,000 N / mm at 25°C. 2 More than 15,000N / mm 2 The encapsulating resin composition is as follows: [2] The encapsulating resin composition according to [1], wherein the low stress material (C) contains a silicone compound. [3] The encapsulating resin composition according to [2], wherein the silicone compound is at least one selected from the group consisting of polyether group-containing silicone polymers, carboxyl group-containing silicone polymers, carboxylic anhydride group-containing silicone polymers, hydroxyl group-containing silicone polymers, epoxy group-containing silicone polymers, amino group-containing silicone polymers, and thiol group-containing silicone polymers. [4] The encapsulating resin composition according to [3], wherein the polyether group-containing silicone polymer is a block copolymer. [5] The encapsulating resin composition according to [4], wherein the polyether group-containing silicone polymer is a polysiloxane-polyalkylene glycol block copolymer. [6] The encapsulating resin composition according to any one of [1] to [5], wherein the inorganic filler (A) is at least one selected from the group consisting of silica, alumina, silicon carbide, aluminum nitride, boron nitride, silicon nitride, and magnesium oxide. [7] The encapsulating resin composition according to any one of [1] to [6], wherein the encapsulating resin composition is cured at 175°C for 4 hours, and the cured product has an average coefficient of linear expansion CTE1 below the glass transition temperature of 13 ppm / °C or more. [8] The encapsulating resin composition according to any one of [1] to [7], wherein the encapsulating resin composition is cured at 175°C for 4 hours, and the cured product has an average coefficient of linear expansion CTE2 at temperatures equal to or higher than the glass transition temperature of 45 ppm / °C or more. [9] The encapsulating resin composition according to any one of [1] to [8], wherein the encapsulating resin composition is cured at 175°C for 4 hours, and the cured product has a glass transition temperature of 140°C or higher.

[10] The encapsulating resin composition is cured at 175°C for 4 hours, and the cured product has a bending strength of 30 N / mm at 25°C. 2 More than 200N / mm 2 The encapsulating resin composition according to any one of [1] to [9], which is:

[11] The encapsulating resin composition according to any one of [1] to

[10] , wherein the encapsulating resin composition is cured at 175°C for 4 hours, and the cured product has a fracture toughness (K1c) of 1.5 MPa / √m or more.

[12] A semiconductor device including a memory mounted on a substrate; a sealing material that seals the semiconductor element, A semiconductor device, wherein the encapsulant is a cured product of the encapsulating resin composition according to any one of [1] to

[11] . [Effects of the Invention]

[0008] According to the present invention, it is possible to provide an encapsulating resin composition that can provide a semiconductor device with excellent product reliability. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view showing a configuration of a semiconductor device according to an embodiment. [Figure 2] 1 is a cross-sectional view showing a configuration of a semiconductor device according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all drawings, similar components are denoted by similar reference numerals, and their description will be omitted where appropriate. For example, "1 to 10" represents "1 or more" to "10 or less" unless otherwise specified.

[0011] The encapsulating resin composition of the present embodiment contains an inorganic filler (A), an epoxy resin (B), and a low-stress material (C), and the encapsulating resin composition is cured at 175°C for 4 hours to produce a cured product having a flexural modulus of 5,000 N / mm at 25°C. 2 More than 15,000N / mm 2 The following is the result.

[0012] The encapsulating resin composition of the present embodiment has a flexural modulus at 25°C of the cured product obtained by curing at 175°C for 4 hours within the above range, and therefore, a semiconductor device in which a semiconductor element mounted on a substrate is encapsulated with an encapsulant obtained from the composition has improved product reliability.

[0013] The present invention was completed based on the discovery that the flexural modulus of a cured product of an encapsulating resin composition within a predetermined range results in excellent mechanical strength of the encapsulant. Furthermore, the difference in the linear expansion coefficient between the encapsulant and the substrate constituting the semiconductor device is reduced, thereby improving the product reliability of the semiconductor device. In other words, the present invention was completed based on the discovery that the flexural modulus of a cured product within a predetermined range results in an excellent balance between the mechanical strength and the linear expansion coefficient of the encapsulant. That is, in the present invention, the flexural modulus of the encapsulant can be used as an index of the product reliability of the semiconductor device.

[0014] [Inorganic filler (A)] As the inorganic filler (A), any known inorganic filler can be used as long as it can achieve the effects of the present invention. In this embodiment, examples of the inorganic filler (A) include silica, alumina, silicon carbide, aluminum nitride, boron nitride, silicon nitride, magnesium oxide, etc., and at least one selected from these can be used. In this embodiment, from the viewpoint of the effects of the present invention, it is preferable to use alumina as the inorganic filler (A).

[0015] The lower limit of the amount of inorganic filler in the encapsulating resin composition is preferably 60% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more, relative to 100% by mass of the encapsulating resin composition, from the viewpoint of suppressing an increase in moisture absorption amount and a decrease in strength due to curing of the encapsulating resin composition.

[0016] Furthermore, from the viewpoints of flowability and moldability, the upper limit of the amount of inorganic filler in the encapsulating resin composition is preferably 98% by mass or less, more preferably 97% by mass or less, and even more preferably 96% by mass or less, relative to 100% by mass of the encapsulating resin composition.

[0017] [Epoxy resin (B)] As the epoxy resin (B), any known epoxy resin can be used as long as the effects of the present invention are achieved. In this embodiment, examples of the epoxy resin (B) include epoxidized novolac resins obtained by condensing or co-condensing phenols such as phenol, cresol, xylenol, resorcinol, catechol, bisphenol A, bisphenol F, etc. and / or naphthols such as α-naphthol, β-naphthol, dihydroxynaphthalene, etc. with compounds having an aldehyde group such as formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, salicylaldehyde, etc., under an acidic catalyst, such as phenol novolac epoxy resins and cresol novolac epoxy resins; diglycidyl ethers of bisphenol A, bisphenol F, bisphenol S, bisphenol A / D, etc.; biphenyl epoxy resins which are diglycidyl ethers of alkyl-substituted or unsubstituted biphenols; phenol aralkyl epoxy resins and biphenyl aralkyl epoxy resins synthesized from phenols and dimethoxy-para-xylene or bis(methoxymethyl)biphenyl; naphthol aralkyl epoxy resins; glycidyl ester type epoxy resins obtained by reacting epichlorohydrin with polybasic acids such as phthalic acid or dimer acid; glycidylamine type epoxy resins obtained by reacting epichlorohydrin with polyamines such as diaminodiphenylmethane or isocyanuric acid; dicyclopentadiene type epoxy resins which are epoxidized products of co-condensation resins of dicyclopentadiene and phenols; triphenolmethane type epoxy resins, trimethylolpropane type epoxy resins; terpene-modified epoxy resins; linear aliphatic epoxy resins obtained by oxidizing olefin bonds with peracids such as peracetic acid; aliphatic multifunctional epoxy resins; multifunctional alicyclic epoxy resins; and epoxy resins obtained by modifying these epoxy resins with silicone, acrylonitrile, butadiene, isoprene-based rubber, polyamide-based resin, or the like.Among these, from the viewpoint of improving the bending strength of the resin composition, it is preferable to contain one or more compounds selected from the group consisting of biphenyl-type epoxy resins, biphenylaralkyl-type epoxy resins, cresol novolac-type epoxy resins, aromatic polyfunctional epoxy resins, aliphatic polyfunctional epoxy resins, and polyfunctional alicyclic epoxy resins. The epoxy resin (B) may be used alone or in combination of two or more of the above specific examples.

[0018] The lower limit of the amount of the epoxy resin (B) in the encapsulating resin composition is preferably 2% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more, relative to 100% by mass of the encapsulating resin composition, from the viewpoint of maintaining various physical properties including the curability of conventional encapsulating resin compositions.

[0019] Furthermore, the upper limit of the amount of the epoxy resin (B) in the encapsulating resin composition is preferably 15% by mass or less, more preferably 12% by mass or less, and even more preferably 10% by mass or less, relative to 100% by mass of the encapsulating resin composition, from the viewpoint of improving the high-temperature reliability and bending strength of a cured product obtained using the encapsulating resin composition.

[0020] [Low stress material (C)] As the low stress material (C), any known low stress material can be used as long as it can achieve the effects of the present invention. In this embodiment, the low stress material (C) can include a silicone compound. Examples of the silicone compound include polyether group-containing silicone polymers, carboxyl group-containing silicone polymers, carboxylic anhydride group-containing silicone polymers, hydroxyl group-containing silicone polymers, epoxy group-containing silicone polymers, amino group-containing silicone polymers, and thiol group-containing silicone polymers, and at least one selected from these can be used.

[0021] The polyether group-containing silicone polymer may be a polysiloxane-polyalkylene glycol block copolymer.

[0022] Examples of the carboxyl group-containing silicone polymer include M69B (manufactured by Kyushu Sumitomo Bakelite Co., Ltd.) and DOWSIL BY 16-880 Fluid (manufactured by Dow-Toray Industries, Inc.). Examples of the carboxylic acid anhydride group-containing silicone polymer include X-22-168B (manufactured by Shin-Etsu Chemical Co., Ltd.).

[0023] Examples of the hydroxyl group-containing silicone polymer include DOWSIL BY 16-892 (manufactured by Dow-Toray). Examples of the epoxy group-containing silicone polymer include FZ-3730 (manufactured by Dow Corning Toray Co., Ltd.) and DOWSIL SF 8411 Fluid (manufactured by Dow Toray Co., Ltd.).

[0024] Examples of the amino group-containing silicone polymer include DOWSIL FZ-3785 (manufactured by Dow-Toray). Examples of the thiol group-containing silicone polymer include X-22-167C (manufactured by Shin-Etsu Chemical Co., Ltd.).

[0025] Among these, the silicone compound is preferably a polysiloxane-polyalkylene glycol block copolymer from the viewpoint of the effects of the present invention.

[0026] The encapsulating resin composition of the present embodiment contains a silicone compound, which provides the encapsulating material with excellent mechanical strength. Furthermore, even when the encapsulating material contains a large amount of inorganic filler, the difference in linear expansion coefficient between the encapsulating material and the substrate and other components constituting the semiconductor device is small, thereby improving the product reliability of the semiconductor device.

[0027] The lower limit of the amount of the low stress material (C) in the encapsulating resin composition is preferably 0.1 mass % or more, more preferably 0.2 mass % or more, and even more preferably 0.5 mass % or more, relative to 100 mass % of the encapsulating resin composition, from the viewpoints of adjusting the flexural modulus of the obtained cured product within a predetermined range and improving the linear expansion coefficient.

[0028] Furthermore, the upper limit of the amount of the low stress material (C) in the encapsulating resin composition is preferably 10 mass % or less, more preferably 5 mass % or less, and even more preferably 3 mass % or less, relative to 100 mass % of the encapsulating resin composition, from the viewpoint of improving the strength and linear expansion coefficient of the obtained cured product.

[0029] [Other ingredients] The encapsulating resin composition of the present embodiment may contain, in addition to the above components, a curing agent, a curing accelerator, a coupling agent, and the like.

[0030] (hardening agent) Examples of curing agents that can be used in this embodiment include known curing agents that are generally used in encapsulating resin compositions, such as novolac-type phenolic resins obtained by condensing or co-condensing phenols (e.g., phenol, cresol, resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol, aminophenol, etc.) and / or naphthols (e.g., α-naphthol, β-naphthol, dihydroxynaphthalene, etc.) with compounds having an aldehyde group (e.g., formaldehyde, benzaldehyde, salicylaldehyde, etc.) under an acidic catalyst, polyfunctional phenolic resins (e.g., triphenylmethane-type phenolic resins and biphenylene skeleton-containing polyfunctional phenolic resins), phenol aralkyl-type phenolic resins (e.g., dicyclopentadiene-type phenolic resins) synthesized from phenols and / or naphthols with dimethoxyparaxylene or bis(methoxymethyl)biphenyl, dicyclopentadiene-type phenolic resins, and terpene-modified phenolic resins. Among these, it is preferable to contain one or two of polyfunctional phenolic resins and phenol aralkyl phenolic resins, and it is more preferable to contain a triphenylmethane phenolic resin or a biphenylene skeleton-containing polyfunctional phenolic resin. These may be used alone or in combination of two or more.

[0031] (curing accelerator) The curing accelerator has the function of accelerating the reaction between the reactive groups of the thermosetting resin and the reactive groups of the curing agent, and any conventionally known curing accelerator can be used. Specific examples of the curing accelerator include phosphorus-containing compounds such as organic phosphines, tetra-substituted phosphonium compounds, phosphobetaine compounds, adducts of phosphine compounds and quinone compounds, and adducts of phosphonium compounds and silane compounds; and nitrogen-containing compounds such as amidines and tertiary amines, exemplified by 1,8-diazabicyclo(5,4,0)undecene-7, benzyldimethylamine, and 2-methylimidazole, as well as quaternary salts of the amidines and amines. One or more of these compounds can be used in combination. Among these, phosphorus-containing compounds are preferred from the viewpoint of curability, and phosphobetaine compounds and adducts of phosphine compounds and quinone compounds are particularly preferred from the viewpoints of solder resistance and fluidity. Furthermore, phosphorus-containing compounds such as tetra-substituted phosphonium compounds and adducts of phosphonium compounds and silane compounds are particularly preferred because of their low mold contamination during continuous molding.

[0032] Examples of organic phosphines that can be used in the encapsulating resin composition include primary phosphines such as ethylphosphine and phenylphosphine; secondary phosphines such as dimethylphosphine and diphenylphosphine; and tertiary phosphines such as trimethylphosphine, triethylphosphine, tributylphosphine, and triphenylphosphine.

[0033] (coupling agent) The coupling agent has the function of improving the adhesion between the thermosetting resin and the inorganic filler when the inorganic filler is contained in the encapsulating resin composition, and for example, a silane coupling agent or the like is used.

[0034] Examples of the silane coupling agent that can be used include amino group-containing silane coupling agents, epoxy group-containing silane coupling agents, (meth)acryloyl group-containing silane coupling agents, mercapto group-containing silane coupling agents, vinyl group-containing silane coupling agents, ureido group-containing silane coupling agents, sulfide group-containing silane coupling agents, and silane coupling agents having a cyclic anhydride structure.

[0035] The amino group-containing silane coupling agent is not particularly limited, but examples thereof include bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldimethoxysilane, N-phenylγ-aminopropyltriethoxysilane, N-phenylγ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropyltriethoxysilane, N-6-(aminohexyl)3-aminopropyltrimethoxysilane, and N-(3-(trimethoxysilylpropyl)-1,3-benzenedimethanamine.

[0036] Examples of epoxy group-containing silane coupling agents include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and γ-glycidylpropyltrimethoxysilane. Examples of the (meth)acryloyl group-containing silane coupling agent include γ-((meth)acryloyloxypropyl)trimethoxysilane, γ-((meth)acryloyloxypropyl)methyldimethoxysilane, and γ-((meth)acryloyloxypropyl)methyldiethoxysilane. An example of a mercapto group-containing silane coupling agent is 3-mercaptopropyltrimethoxysilane. Examples of vinyl group-containing silane coupling agents include vinyltris(β-methoxyethoxy)silane, vinyltriethoxysilane, and vinyltrimethoxysilane. Examples of ureido group-containing silane coupling agents include 3-ureidopropyltriethoxysilane. Examples of sulfide group-containing silane coupling agents include bis(3-(triethoxysilyl)propyl)disulfide and bis(3-(triethoxysilyl)propyl)tetrasulfide. Examples of silane coupling agents having a cyclic anhydride structure include 3-trimethoxysilylpropylsuccinic anhydride, 3-triethoxysilylpropylsuccinic anhydride, and 3-dimethylmethoxysilylpropylsuccinic anhydride. As the silane coupling agent, it is preferable to use an amino group-containing silane coupling agent, which can further improve the flowability of the encapsulating resin composition.

[0037] In addition to the other components described above, colorants such as carbon black, red iron oxide, and titanium oxide; ion scavengers; natural waxes such as carnauba wax, synthetic waxes such as polyethylene wax, and inorganic flame retardants such as higher fatty acids such as stearic acid and zinc stearate, metal salts thereof, metal hydroxides, and composite metal hydroxides may also be blended as appropriate.

[0038] The encapsulating resin composition of the present embodiment can be obtained by mixing component (A), component (B), and component (C), and further the other components described above, as needed, by a method commonly used in the art.

[0039] <Sealing resin composition> The encapsulating resin composition of the present embodiment has the following properties.

[0040] From the viewpoint of the effects of the present invention, the flexural modulus at 25°C of the cured product obtained by curing the encapsulating resin composition of this embodiment at 175°C for 4 hours is 5,000 N / mm 2 More than 15,000N / mm2 Less than 6,000N / mm 2 More than 14,000N / mm 2 or less, more preferably 6,500 N / mm 2 More than 14,000N / mm 2 It can be as follows:

[0041] The encapsulating resin composition of this embodiment is cured at 175°C for 4 hours, and the cured product has a flexural modulus of 100 N / mm at 260°C. 2 More than 600N / mm 2 Less than or equal to 150N / mm 2 More than 550N / mm 2 or less, more preferably 200 N / mm 2 More than 500N / mm 2 It can be as follows: When the flexural modulus at 260°C is within the above range, the product reliability of a semiconductor device including the resulting cured product as an encapsulant is further improved.

[0042] The encapsulating resin composition of the present embodiment can be cured at 175°C for 4 hours to produce a cured product having an average coefficient of linear expansion CTE1 below the glass transition temperature of 13 ppm / °C or more, preferably 14 ppm / °C or more, and more preferably 15 ppm / °C or more. By satisfying the above average coefficient of linear expansion CTE1 in addition to the above flexural modulus, the product reliability of a semiconductor device including the resulting cured product as an encapsulant is further improved.

[0043] The encapsulating resin composition of the present embodiment can be cured at 175°C for 4 hours to produce a cured product having an average coefficient of linear expansion CTE2 at temperatures equal to or higher than the glass transition temperature of 45 ppm / °C or more, preferably 46 ppm / °C or more, and more preferably 47 ppm / °C or more. By satisfying the above average coefficient of linear expansion CTE2 in addition to the above flexural modulus, the product reliability under high temperatures of a semiconductor device including the resulting cured product as an encapsulant is improved.

[0044] In the present invention, the average linear expansion coefficients CTE1 and CTE2 of the cured product made of the encapsulating resin composition are within predetermined ranges, thereby reducing the difference in linear expansion coefficient between the encapsulating material and the substrate, etc. that constitutes the semiconductor device, thereby further reducing the generated stress. Furthermore, since the flexural modulus of the cured product is within the predetermined range, the generated stress can be alleviated and a better balance with the mechanical strength of the encapsulating material is achieved, thereby improving the product reliability of the semiconductor device.

[0045] The encapsulating resin composition of this embodiment can be cured at 175°C for 4 hours to produce a cured product having a glass transition temperature of 140°C or higher, preferably 150°C or higher. By satisfying the above-mentioned glass transition temperature in addition to the above-mentioned flexural modulus, the product reliability under high temperatures of a semiconductor device containing the resulting cured product as an encapsulant is improved.

[0046] The encapsulating resin composition of this embodiment was cured at 175°C for 4 hours, and the cured product had a bending strength of 30 N / mm at 25°C. 2 More than 200N / mm 2 Less than 40N / mm 2 More than 180N / mm 2 or less, more preferably 50N / mm 2 More than 150N / mm 2 It can be less than or equal to. This allows the sealing material to have excellent strength, making it possible to provide a semiconductor device with even greater reliability.

[0047] The encapsulating resin composition of this embodiment was cured at 175°C for 4 hours, and the cured product had a bending strength of 3 N / mm at 260°C. 2 More than 30N / mm 2 Less than 4N / mm 2 More than 25N / mm 2 or less, more preferably 5N / mm 2 More than 20N / mm 2 It can be less than or equal to. This allows the strength of the sealing material to be excellent even under the usage environment, making it possible to provide a semiconductor device with higher reliability.

[0048] The encapsulating resin composition of this embodiment can be cured at 175° C. for 4 hours to produce a cured product with a fracture toughness (K1c) of 1.5 MPa / √m or more, preferably 1.6 MPa / √m or more. This makes it possible to provide a semiconductor device including these components that is more reliable.

[0049] By appropriately selecting the combination and amounts of the inorganic filler (A), epoxy resin (B), and low-stress material (C), it is possible to adjust the flexural modulus at 25°C, CTE1, CTE2, glass transition temperature, flexural strength, and fracture toughness of the cured product.

[0050] <Semiconductor device> The semiconductor device of this embodiment has a semiconductor element encapsulated with a cured product of the encapsulating resin composition of this embodiment. Specific examples of the semiconductor element include a memory, an integrated circuit, a large-scale integrated circuit, a transistor, a thyristor, a diode, and a solid-state imaging device. Even if the semiconductor element includes a memory that generates a large amount of heat, the semiconductor element has excellent heat dissipation properties because it is encapsulated with an encapsulant made of the composition of this embodiment. Furthermore, since the encapsulant has a high linear expansion coefficient, the difference in linear expansion coefficient between components such as the substrate that constitute the semiconductor device is small, resulting in excellent product reliability of the semiconductor device.

[0051] The substrate of the semiconductor device is, for example, a wiring board such as an interposer or a lead frame, and the semiconductor element is electrically connected to the substrate by wire bonding, flip-chip connection, or the like.

[0052] Examples of semiconductor devices obtained by encapsulating a semiconductor element by encapsulation molding using an encapsulating resin composition include MAP (Mold Array Package), QFP (Quad Flat Package), SOP (Small Outline Package), CSP (Chip Size Package), QFN (Quad Flat Non-leaded Package), SON (Small Outline Non-leaded Package), BGA (Ball Grid Array), LF-BGA (Lead Flame BGA), FCBGA (Flip Chip BGA), MAPBGA (Molded Array Process BGA), eWLB (Embedded Wafer-Level BGA), Fan-In type eWLB, and Fan-Out type eWLB. The following will explain this in more detail with reference to the drawings.

[0053] 1 and 2 are cross-sectional views showing the configuration of a semiconductor device, but in this embodiment, the configuration of the semiconductor device is not limited to those shown in FIGS. First, the semiconductor device 100 shown in FIG. 1 includes a semiconductor element 20 mounted on a substrate 30, and a sealing material 50 that seals the semiconductor element 20. The encapsulant 50 is made of a cured product obtained by curing the encapsulating resin composition of the present embodiment described above.

[0054] 1 also illustrates an example in which the substrate 30 is a circuit board. In this case, as shown in FIG. 1, a plurality of solder balls 60, for example, are formed on the other surface of the substrate 30 opposite to the surface on which the semiconductor element 20 is mounted. The semiconductor element 20 is mounted on the substrate 30 and electrically connected to the substrate 30 via wires 40. Alternatively, the semiconductor element 20 may be flip-chip mounted on the substrate 30. Here, the wires 40 are not limited to, but examples thereof include Ag wires, Ni wires, Cu wires, Au wires, and Al wires. Preferably, the wires 40 are made of Ag, Ni, or Cu, or an alloy containing one or more of these.

[0055] The sealing material 50 seals the semiconductor element 20, for example, by covering the other surface of the semiconductor element 20 opposite to the surface facing the substrate 30. In the example shown in FIG. 1 , the sealing material 50 is formed to cover the other surface and the side surface of the semiconductor element 20.

[0056] In this embodiment, the encapsulant 50 is made of a cured product of the encapsulating resin composition described above. Therefore, in the semiconductor device 100, the encapsulant 50 and the wires 40 have excellent adhesion, which makes the semiconductor device 100 highly reliable. The encapsulant 50 can be formed by encapsulating a resin composition using a known method such as transfer molding or compression molding.

[0057] 2 is a cross-sectional view showing the configuration of a semiconductor device 100 according to this embodiment, illustrating an example different from that shown in FIG. 2. The semiconductor device 100 shown in FIG. 2 uses a lead frame as the substrate 30. In this case, the semiconductor element 20 is mounted, for example, on a die pad 32 of the substrate 30, and is electrically connected to outer leads 34 via wires 40. The encapsulant 50 is made of a cured product of the encapsulating resin composition according to this embodiment, similar to the example shown in FIG. 1.

[0058] Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various configurations other than those described above can be adopted as long as they do not impair the effects of the present invention. [Example]

[0059] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0060] Inorganic filler 1: Alumina (Micron Corporation, AX3-20R, particle size D 50 = 5 μm) Inorganic filler 2: Alumina (Admatechs, SBM-1X40V, particle size D50 =0.6μm) Colorant: Carbon black (Mitsubishi Chemical, MA-600) Coupling agent: Phenylaminopropyltrimethoxysilane (CF-4083, manufactured by Dow Corning Toray Co., Ltd.)

[0061] Epoxy resin: 4,4'-biphenyl type epoxy resin (YX-4000K, manufactured by Mitsubishi Chemical Corporation) Hardener: Trisphenylmethane mixed phenolic resin (HE910-20, manufactured by Air Water) Release agent: Glycerin trimontanate ester (WE-4, Clariant Chemicals) Ion scavenger: Hydroxytalcite (manufactured by Toagosei Chemical Industry Co., Ltd.)

[0062] Catalyst 1: Tetraphenylphosphonium 4,4'-sulfonyldiphenolate Catalyst 2: Tetraphenylphosphonium bis(naphthalene-2,3-dioxy)phenylsilicate

[0063] Silicone Compound 1: A 100 mL separable flask was charged with 6.0 g of silicone oil (X-22-168A, weight-average molecular weight 2000, manufactured by Shin-Etsu Chemical Co., Ltd.) modified with maleic anhydride at both ends and 10.0 g of polytetramethylene ether glycol (PTMG2000, weight-average molecular weight 2000, manufactured by Mitsubishi Chemical Corporation) and purged with nitrogen. The mixture was then heated to 100°C and reacted for 1.5 hours to yield a polysiloxane-polyalkylene glycol block copolymer. The resulting polysiloxane-polyalkylene glycol block copolymer had a PDMS ratio of 30% by mass, a weight-average molecular weight of 6000, and a carboxylic acid content of 2500 g / mol.

[0064] Silicone Compound 2: A 100 mL separable flask was charged with 6.0 g of silicone oil modified at both ends with maleic anhydride (X-22-168A, manufactured by Shin-Etsu Chemical Co., Ltd., weight-average molecular weight 2000) and 10.0 g of polytetramethylene ether glycol (PTMG2000, manufactured by Mitsubishi Chemical Corporation, weight-average molecular weight 2000), and the flask was purged with nitrogen. The flask was then heated to 100°C and reacted for 0.5 hours to obtain a polysiloxane-polyalkylene glycol block copolymer. A 100 mL separable flask was charged with 40 g of the resulting polysiloxane-polyalkylene glycol block copolymer intermediate and 5.06 g of triethyl orthoacetate. The mixture was then purged with nitrogen and heated to 100°C for 1.5 hours. The mixture was then dried under vacuum at 80°C for 12 hours to remove by-products, yielding a polysiloxane-polyalkylene glycol block copolymer. The resulting polysiloxane-polyalkylene glycol block copolymer had a PDMS ratio of 30% by mass, a weight-average molecular weight of 6000, and a carboxylic acid content of 1300 g / mol.

[0065] Silicone Compound 3: A 100 mL separable flask was charged with 4.0 g of silicone oil modified at both ends with maleic anhydride (X-22-168A, manufactured by Shin-Etsu Chemical Co., Ltd., weight-average molecular weight 2000) and 10.0 g of polytetramethylene ether glycol (PTMG2000, manufactured by Mitsubishi Chemical Corporation, weight-average molecular weight 2000), and the flask was purged with nitrogen. The flask was then heated to 80°C and reacted for 0.5 hours to obtain a polysiloxane-polyalkylene glycol block copolymer. A 100 mL separable flask was charged with 40 g of the resulting polysiloxane-polyalkylene glycol block copolymer intermediate and 5.06 g of triethyl orthoacetate. The mixture was then purged with nitrogen and heated to 80°C for 1.5 hours to react. The mixture was then dried under vacuum at 80°C for 12 hours to remove by-products, yielding a polysiloxane-polyalkylene glycol block copolymer. The resulting polysiloxane-polyalkylene glycol block copolymer had a PDMS ratio of 20% by mass, a weight-average molecular weight of 4000, and a carboxylic acid content of 1300 g / mol.

[0066] (Flexural modulus and flexural strength) The encapsulating resin composition was injected into a mold using a low-pressure transfer molding machine (KTS-30 manufactured by Kotaki Seiki Co., Ltd.) under conditions of a mold temperature of 175°C, an injection pressure of 10.0 MPa, and a curing time of 120 seconds. This resulted in a molded product with a width of 10 mm, a thickness of 4 mm, and a length of 80 mm. The molded product was then post-cured at 175°C for 4 hours. This resulted in the preparation of test specimens for evaluation of mechanical strength. The flexural modulus (N / mm) of the test specimens at 260°C or room temperature (25°C) was measured. 2 ) and bending strength (N / mm 2 ) was measured in accordance with JIS K 6911.

[0067] (Coefficient of linear expansion (CTE1 and CTE2)) The measurement was carried out in the following manner. (1) Using a transfer molding machine, the encapsulating resin composition was injection molded under the conditions of a mold temperature of 175°C, an injection pressure of 10.0 MPa, and a curing time of 120 seconds to obtain a molded product of 15 mm x 4 mm x 3 mm. (2) The obtained molded article was heated in an oven at 175°C for 4 hours to be fully cured, and a test piece (cured product) for measurement was obtained. (3) Measurements were performed using a thermomechanical analyzer (Seiko Instruments, TMA100) at a temperature range of 0°C to 320°C and a heating rate of 5°C / min. From the measurement results, the average coefficient of linear expansion below the glass transition temperature (CTE1) and the average coefficient of linear expansion above the glass transition temperature (CTE2) were calculated. The units for CTE1 and CTE2 are ppm / °C.

[0068] (glass transition temperature (Tg)) The encapsulating resin composition was injected into a transfer molding machine at a mold temperature of 175°C, injection pressure of 9.8 MPa, and curing time of 3 minutes to obtain a 15mm x 4mm x 4mm test piece. The test piece was then post-cured at 175°C for 4 hours and then measured using a thermomechanical analyzer (Seiko Instruments Inc., TMA100) at a temperature range of 0°C to 320°C and a heating rate of 5°C / min. The glass transition temperature Tg (°C) was calculated from the measurement results.

[0069] (Fracture toughness value (K1c)) The resin compositions obtained in each example were measured in accordance with the K1c method specified in ASTM D5045-91. Specifically, the resin compositions were cut to a length of 50 mm, width B = 5 mm, and thickness W = 10 mm, and a notch 3.5 mm deep in the thickness direction was made in the center of the length direction, and cured at 175°C for 4 hours. Furthermore, a scratch 0.1 mm deep in the thickness direction was made with a razor at the tip of the notch in the cured product. The total crack length was a = 3.6 mm. A three-point bending test was then performed using an STB-1225S Tensilon manufactured by Orientec Co., Ltd., at a measurement temperature of 25°C, a speed of 10 mm / min, and a support distance S = 40 mm, and the fracture toughness value (K1c (MPa m)) was calculated based on the following formula: 1 / 2 )) was calculated. Q is the load (N). K1c=((P Q ×S) / (B×W 3 / 2 ))×f(a / W) f(a / W)=(3(a / W) 1 / 2 [1.99-(a / W)(1-a / W){2.15-3.9(a / W)+2.7(a / W) 2 ]) / (2{881+2(a / W)}{1-(a / W)} 3 / 2 )

[0070] [Table 1]

[0071] As shown in Table 1, the encapsulating resin composition of the present invention described in the examples has a flexural modulus within a predetermined range for a cured product made of the composition, and therefore the encapsulating material has excellent mechanical strength. Furthermore, the linear expansion coefficient of the encapsulating material is increased, thereby reducing the difference in the linear expansion coefficient between the encapsulating material and the substrate or the like that constitutes the semiconductor device, thereby improving the product reliability of the semiconductor device. [Explanation of symbols]

[0072] 20 Semiconductor elements 30 boards 32 die pad 34 outer lead 40 wire 50 Encapsulating material 60 solder balls 100 Semiconductor device

Claims

1. An encapsulating resin composition comprising an inorganic filler (A), an epoxy resin (B), and a low-stress material (C), The encapsulating resin composition was cured at 175°C for 4 hours, and the cured product had a flexural modulus of 5,000 N / mm at 25°C. ２ Above, 15,000N / mm ２ The encapsulating resin composition is as follows:

2. The encapsulating resin composition according to claim 1 , wherein the low stress material (C) includes a silicone compound.

3. 3. The encapsulating resin composition according to claim 2, wherein the silicone compound is at least one selected from the group consisting of a polyether group-containing silicone polymer, a carboxyl group-containing silicone polymer, a carboxylic anhydride group-containing silicone polymer, a hydroxyl group-containing silicone polymer, an epoxy group-containing silicone polymer, an amino group-containing silicone polymer, and a thiol group-containing silicone polymer.

4. The encapsulating resin composition according to claim 3 , wherein the polyether group-containing silicone polymer is a block copolymer.

5. 5. The encapsulating resin composition according to claim 4, wherein the polyether group-containing silicone polymer is a polysiloxane-polyalkylene glycol block copolymer.

6. 2. The encapsulating resin composition according to claim 1, wherein the inorganic filler (A) is at least one selected from the group consisting of silica, alumina, silicon carbide, aluminum nitride, boron nitride, silicon nitride, and magnesium oxide.

7. 2. The encapsulating resin composition according to claim 1, wherein a cured product obtained by curing the encapsulating resin composition at 175°C for 4 hours has an average coefficient of linear expansion CTE1 below the glass transition temperature of 13 ppm / °C or more.

8. 2. The encapsulating resin composition according to claim 1, wherein a cured product obtained by curing the encapsulating resin composition at 175°C for 4 hours has an average coefficient of linear expansion CTE2 at a temperature equal to or higher than a glass transition temperature of 45 ppm / °C or more.

9. 2. The encapsulating resin composition according to claim 1, wherein the encapsulating resin composition is cured at 175°C for 4 hours and the cured product has a glass transition temperature of 140°C or higher.

10. The encapsulating resin composition was cured at 175°C for 4 hours, and the cured product had a bending strength of 30 N / mm at 25°C. ２ More than 200N / mm ２ The encapsulating resin composition according to claim 1 , wherein:

11. 2. The encapsulating resin composition according to claim 1, wherein the encapsulating resin composition is cured at 175°C for 4 hours, and the cured product has a fracture toughness (K1c) of 1.5 MPa / √m or more.

12. a semiconductor device including a memory mounted on a substrate; a sealing material that seals the semiconductor element, A semiconductor device, wherein the encapsulant is a cured product of the encapsulating resin composition according to any one of claims 1 to 11.

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