Sealing resin composition, electronic component device, and method for producing electronic component device

Abstract

This sealing resin composition contains a curable resin and a neutron absorber. The content of the neutron absorber is 0.3-24 mass% relative to the total mass of the sealing resin composition. The sealing resin composition makes it possible to sufficiently suppress the occurrence of soft errors due to neutrons even when applied to an electronic component device mounted to a spacecraft.

Description

Encapsulating resin composition, electronic component device, and method for manufacturing an electronic component device

[0001] This disclosure relates to a encapsulating resin composition, an electronic component device, and a method for manufacturing an electronic component device.

[0002] Conventionally, temporary errors can occur in semiconductor memory such as RAM (Static Random Access Memory) and DRAM (Dynamic Random Access Memory). Unlike physical hardware damage, these errors are called soft errors. Soft errors can be caused by alpha particles emitted from trace amounts of radioactive materials contained in the semiconductor device's components, as well as neutrons in cosmic rays.

[0003] As a method for suppressing the occurrence of soft errors caused by neutrons, for example, Patent Document 1 discloses the use of a resin composition containing 50% by mass or more of a compound having neutron absorption ability (such as an oxide containing at least one element selected from the group consisting of gadolinium, boron, samarium, cadmium, and europium) as a encapsulant for semiconductor devices.

[0004] Japanese Patent Publication No. 2021-181559

[0005] The amount of neutron radiation (radiation per unit time) varies with altitude, and the amount of radiation in outer space is far greater than that at the Earth's surface and in the stratosphere. Therefore, even if a sealing resin composition shows a soft error suppression effect at the Earth's surface or in the stratosphere, it may not be able to sufficiently suppress soft errors when applied to electronic components mounted on spacecraft such as artificial satellites, space stations, and probes.

[0006] One aspect of this disclosure aims to provide a sealing resin composition that can sufficiently suppress the occurrence of neutron-induced soft errors, even when applied to electronic component devices mounted on spacecraft. Another aspect of this disclosure aims to provide an electronic component device using such a sealing resin composition, and a method for manufacturing the electronic component device.

[0007] This disclosure includes the following aspects: [1] A encapsulating resin composition comprising a curable resin and a neutron absorber, wherein the content of the neutron absorber is 0.3% to 24% by mass, based on the total mass of the encapsulating resin composition. [2] The encapsulating resin composition according to [1], wherein the neutron absorber comprises at least one element selected from samarium, gadolinium, and boron. [3] The encapsulating resin composition according to [1] or [2], wherein the neutron absorber comprises at least one element selected from samarium oxide, gadolinium oxide, and boron nitride. [4] The encapsulating resin composition according to any one of [1] to [3], wherein the curable resin is an epoxy resin, and further comprises a phenolic curing agent and an inorganic filler. [5] The encapsulating resin composition according to any one of [1] to [4], used in electronic component devices mounted on spacecraft. [6] An electronic component device comprising an element and a cured product of a sealing resin composition according to any one of [1] to [5] for sealing the element. [7] A method for manufacturing an electronic component device, comprising sealing an element with a sealing resin composition according to any one of [1] to [5].

[0008] According to one aspect of this disclosure, it is possible to provide a sealing resin composition that can sufficiently suppress the occurrence of neutron-induced soft errors, even when applied to electronic component devices mounted on spacecraft. According to another aspect of this disclosure, it is possible to provide an electronic component device using such a sealing resin composition, and a method for manufacturing the electronic component device.

[0009] This figure shows a structural model relating to the embodiment. This figure shows a method for setting the arrangement of particles in the sealing material in the embodiment.

[0010] The present disclosure will be described in detail below. In this specification, numerical ranges indicated using "~" indicate a range that includes the numbers before and after "~" as the minimum and maximum values, respectively. For example, the statement "10 or more" means 10 and numbers greater than 10, and the same applies when the numbers are different. For example, the statement "10 or less" means 10 and numbers less than 10, and the same applies when the numbers are different. In addition, in numerical ranges described in steps, the upper or lower limit of a numerical range in one step may be replaced with the upper or lower limit of a numerical range in another step, or with the values ​​shown in the examples. In this specification, the content of each component in a composition means the total content of multiple types of substances present in the composition, unless otherwise specified, if there are multiple types of substances corresponding to each component in the composition. In this specification, the term "layer" includes not only structures that are formed in a shape that is formed over the entire surface when observed as a plan view, but also structures that are formed in a shape that is formed in part.

[0011] [Sealing Resin Composition] One embodiment of the present disclosure is a sealing resin composition used in electronic component devices mounted on a spacecraft, comprising a curable resin and a neutron absorber. The content of the neutron absorber is 0.3% to 24% by mass, based on the total mass of the sealing resin composition.

[0012] The sealing resin composition according to this embodiment can sufficiently suppress the occurrence of soft errors caused by neutrons, even when applied to semiconductor devices mounted on spacecraft. The inventors speculate that this effect is achieved as follows. First, electronic components mounted on spacecraft such as artificial satellites are used in outer space and are in an environment that is more strongly affected by cosmic rays (radiation) than the Earth's surface and the stratosphere. In such a harsh operating environment, neutrons (primary neutrons) in cosmic rays can be absorbed by neutron absorbers, but at this time, the emission of alpha particles due to (n,α) reactions may also occur. When the emitted alpha particles collide with the constituent materials of the semiconductor device, neutrons (secondary neutrons) are emitted, causing soft errors. In other words, if the content of the neutron absorber exceeds the above upper limit, even if soft errors caused by primary neutrons can be suppressed, soft errors caused by the increase in alpha particles and secondary neutrons become more likely to occur, and as a result, the soft error suppression effect is considered to be insufficient. In other words, the reason why the sealing resin composition according to this embodiment exhibits an excellent soft error suppression effect is that the content ratio of the neutron absorber to 100 parts by mass of the curable resin is within a specific range, so that soft errors caused by secondary neutrons can be sufficiently suppressed in addition to soft errors caused by primary neutrons.

[0013] The type of curable resin included in the encapsulating resin composition is not particularly limited. Examples of curable resins that can be used include thermosetting resins such as epoxy resins, phenolic resins, silicone resins, and polyimide resins. From the viewpoint of balancing the various properties of the encapsulating resin composition, epoxy resins are preferred as the curable resin.

[0014] The type of epoxy resin is not particularly limited as long as it has two or more epoxy groups in one molecule. The epoxy resin may be solid or liquid at 25°C and atmospheric pressure, but it is preferably solid.

[0015] Specifically, novolac-type epoxy resins (phenol novolac-type epoxy resins, orthocresol novolac-type epoxy resins, etc.) are obtained by epoxidizing a novolac resin obtained by condensing or co-condensing a novolac resin obtained by condensing or co-condensing a novolac resin obtained by phenol compounds selected from the group consisting of phenol compounds such as phenol, cresol, xylenol, resorcinol, catechol, bisphenol A, bisphenol F, and naphthol compounds such as α-naphthol, β-naphthol, and dihydroxynaphthalene under an acidic catalyst, with an aliphatic aldehyde compound such as formaldehyde, acetaldehyde, or propionaldehyde, under an acidic catalyst; triphenylmethane-type epoxy resins are obtained by epoxidizing a triphenylmethane-type phenol resin obtained by condensing or co-condensing the above phenol compound with an aromatic aldehyde compound such as benzaldehyde or salicylaldehyde under an acidic catalyst; and novolac resins obtained by co-condensing the above phenol compound and naphthol compound with an aldehyde compound under an acidic catalyst, are epoxidized. Copolymer epoxy resins; diphenylmethane type epoxy resins which are diglycidyl ethers of bisphenol A, bisphenol F, etc.; biphenyl type epoxy resins which are diglycidyl ethers of alkyl-substituted or unsubstituted biphenols; stilbene type epoxy resins which are diglycidyl ethers of stilbene-based phenol compounds; sulfur atom-containing epoxy resins which are diglycidyl ethers of bisphenol S, etc.; glycidyl ether type epoxy resins which are glycidyl ethers of alcohols such as butanediol, polyethylene glycol, and polypropylene glycol; glycidyl ester type epoxy resins which are glycidyl esters of polycarboxylic acid compounds such as phthalic acid, isophthalic acid, and tetrahydrophthalic acid; glycidylamine type epoxy resins in which the active hydrogen bonded to the nitrogen atom of aniline, diaminodiphenylmethane, isocyanuric acid, etc. is substituted with a glycidyl group; dicyclopentadiene type epoxy resins which are epoxidized from a co-condensation resin of dicyclopentadiene and a phenol compound;Alicyclic epoxy resins such as vinylcyclohexene diepoxide, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and 2-(3,4-epoxy)cyclohexyl-5,5-spiro(3,4-epoxy)cyclohexane-m-dioxane, which have epoxidized olefin bonds within the molecule; paraxylylene-modified epoxy resins, which are glycidyl ethers of paraxylylene-modified phenol resins; metaxylylene-modified epoxy resins, which are glycidyl ethers of metaxylylene-modified phenol resins; terpene-modified epoxy resins, which are glycidyl ethers of terpene-modified phenol resins; and dicyclopentadiene-modified phenol resins, which are glycidyl ethers of dicyclopentadiene-modified phenol resins. Examples of epoxy resins include: pentadiene-modified epoxy resins; cyclopentadiene-modified epoxy resins, which are glycidyl ethers of cyclopentadiene-modified phenolic resins; polycyclic aromatic ring-modified epoxy resins, which are glycidyl ethers of polycyclic aromatic ring-modified phenolic resins; naphthalene-type epoxy resins, which are glycidyl ethers of naphthalene ring-containing phenolic resins; halogenated phenol novolac-type epoxy resins; hydroquinone-type epoxy resins; trimethylolpropane-type epoxy resins; linear aliphatic epoxy resins obtained by oxidizing olefin bonds with peracids such as peracetic acid; and aralkyl-type epoxy resins, which are epoxidized aralkyl-type phenolic resins such as phenol aralkyl resins and naphthol aralkyl resins. Furthermore, epoxides of silicone resins and acrylic resins can also be cited as epoxy resins. These epoxy resins may be used individually or in combination of two or more types.

[0016] Among the epoxy resins mentioned above, epoxy resins selected from the group consisting of biphenyl-type epoxy resins, stilbene-type epoxy resins, diphenylmethane-type epoxy resins, sulfur atom-containing epoxy resins, novolac-type epoxy resins, dicyclopentadiene-type epoxy resins, triphenylmethane-type epoxy resins, copolymer-type epoxy resins, and aralkyl-type epoxy resins (these are referred to as "specific epoxy resins") from the viewpoint of balancing reflow resistance and fluidity. Specific epoxy resins may be used individually or in combination of two or more types.

[0017] When the epoxy resin contains a specific epoxy resin, from the viewpoint of exhibiting the performance of the specific epoxy resin, its total content may be 30% by mass or more, or 50% by mass or more, of the total epoxy resin.

[0018] In one embodiment, the epoxy resin may include at least one selected from the group consisting of aralkyl epoxy resins and biphenyl epoxy resins. Furthermore, from the viewpoint of achieving both fluidity and heat resistance, aralkyl epoxy resins and biphenyl epoxy resins may be used in combination.

[0019] If the epoxy resin contains an aralkyl epoxy resin, the content of the aralkyl epoxy resin may be 40% by mass or more, 50% by mass or more, or 60% by mass or more of the total mass of the epoxy resin. Alternatively, the content of the aralkyl epoxy resin may be 100% by mass or less, 90% by mass or less, or 80% by mass or less of the total mass of the epoxy resin.

[0020] If the epoxy resin contains a biphenyl-type epoxy resin, the biphenyl-type epoxy resin content may be 5% by mass or more, 10% by mass or more, or 20% by mass or more of the total mass of the epoxy resin. Alternatively, the biphenyl-type epoxy resin content may be 60% by mass or less, 50% by mass or less, or 40% by mass or less of the total mass of the epoxy resin.

[0021] When using aralkyl epoxy resin and biphenyl epoxy resin in combination, their mass ratio (aralkyl epoxy resin: biphenyl epoxy resin) may be, for example, 40:60 to 95:5, 50:50 to 90:10, or 60:40 to 80:20.

[0022] If the epoxy resin contains at least one selected from the group consisting of aralkyl epoxy resins and biphenyl epoxy resins, the total content of the aralkyl epoxy resin and biphenyl epoxy resin relative to the total mass of the epoxy resin may be 50% by mass or more, 70% by mass or more, or 90% by mass or more.

[0023] As epoxy resins, for example, the following commercially available products can be used: Biphenyl-type epoxy resins: YX-4000 and YX-4000H (Mitsubishi Chemical Corporation, product names), YL-6121H (Mitsubishi Chemical Corporation, product names), etc. Stilbene-type epoxy resins: ESLV-210 (Sumitomo Chemical Co., Ltd., product name), etc. Diphenylmethane-type epoxy resins: YSLV-80XY (Nippon Steel Chemical & Material Co., Ltd., product name), etc. Sulfur atom-containing epoxy resins: YSLV-120TE (Nippon Steel Chemical & Material Co., Ltd., product name), etc. Novolac-type epoxy resins: ESCN-190, ESCN-195 (Sumitomo Chemical Co., Ltd., product names), N-770, N-775 (DIC Corporation, product names), YDAN-1000-10C (Nippon Steel Chemical & Material Co., Ltd., product names), etc. Dicyclopentadiene type epoxy resin: HP-7200 (DIC Corporation, product name) Triphenylmethane type epoxy resin: 1032H60 (Mitsubishi Chemical Corporation, product name), EPPN-502H (Nippon Kayaku Co., Ltd., product name), etc. Copolymer type epoxy resin: NC-7300 (Nippon Kayaku Co., Ltd., product name), Epiclon HP-5000 (DIC Corporation, product name), etc. Aalkyl type epoxy resin: CER-3000 (Nippon Kayaku Co., Ltd., product name), ESN-175 (Nippon Steel Chemical & Material Co., Ltd., product name), etc.

[0024] The epoxy equivalent of the epoxy resin is not particularly limited. From the viewpoint of balancing various properties such as moldability, reflow resistance, and electrical reliability, the epoxy equivalent of the epoxy resin may be 100 g / eq to 1000 g / eq, 150 g / eq to 500 g / eq, or 160 g / eq to 300 g / eq. The epoxy equivalent of the epoxy resin shall be the value measured by the method in accordance with JIS K 7236:2009.

[0025] When the epoxy resin is solid, its softening point or melting point is not particularly limited. From the viewpoint of moldability and reflow resistance, the softening point or melting point may be 40°C to 180°C. From the viewpoint of handling during the preparation of the epoxy resin composition, the softening point or melting point may be 50°C to 130°C. The melting point of the epoxy resin shall be the value measured by differential scanning calorimetry (DSC), and the softening point of the epoxy resin shall be the value measured by the method (ring-sphere method) in accordance with JIS K 7234:1986.

[0026] The epoxy resin content in the epoxy resin composition may be 0.5% to 50% by mass, or 2% to 30% by mass, from the viewpoint of strength, fluidity, heat resistance, moldability, etc.

[0027] The neutron absorber included in the sealing resin composition is not particularly limited as long as it has neutron absorption capacity. As the neutron absorber, for example, a compound containing an element having a neutron absorption cross-section of 500 barn or more and 50,000 barn or less can be used. Specifically, examples include oxides, nitrides, carbides, hydroxides, etc., containing at least one element selected from samarium, gadolinium, boron, cadmium, and europium. In addition, zinc borate may be used as a compound containing boron.

[0028] The neutron absorber may be a compound containing at least one element selected from samarium, gadolinium, and boron, from the viewpoint of being an insulator and having an appropriate particle size that can be incorporated into resins, and may further be at least one selected from samarium oxide, gadolinium oxide, and boron nitride.

[0029] The neutron absorber content is 0.3% to 24% by mass, based on the total mass of the sealing resin composition. From the viewpoint of improving the soft error suppression effect, this content may be 0.31% or more by mass, 0.62% or more by mass, or 0.73% or more by mass. Furthermore, from the viewpoint of moldability when sealing the element with the sealing resin composition, this content may be 11.4% or less by mass, 20.7% or less by mass, or 23.6% or less by mass, based on the total mass of the sealing resin composition.

[0030] The shape of the neutron absorber is not particularly limited, and particulate materials, for example, can be used. The average particle size of the neutron absorber may be 0.1 to 1 μm, 1 to 10 μm, or 10 to 50 μm, from the viewpoint of moldability when sealing the device with the sealing resin composition. The average particle size of the neutron absorber shall be the value measured by laser diffraction / scattering.

[0031] The encapsulating resin composition may further contain a curing agent. The curing agent can be appropriately selected depending on the type of curable resin. For example, when epoxy resin is used as the curable resin, the curing agent may be a phenolic curing agent.

[0032] Examples of phenolic curing agents include phenolic resins and polyhydric phenolic compounds having two or more phenolic hydroxyl groups in one molecule. Phenolic curing agents may be solid or liquid at 25°C and atmospheric pressure, but are preferably solid.

[0033] Specifically, a novolac-type phenolic resin obtained by condensing or co-condensing the above phenolic compounds with polyhydric phenol compounds such as resorcinol, catechol, bisphenol A, bisphenol F, and substituted or unsubstituted biphenols; at least one phenolic compound selected from the group consisting of phenol compounds such as phenol, m-cresol, p-cresol, xylenol, resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol, aminophenol, and naphthol compounds such as α-naphthol, β-naphthol, and dihydroxynaphthalene, and an aldehyde compound such as formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, and salicylaldehyde under an acidic catalyst; and the above phenolic compounds with dimethoxyparaxylene, bis(methoxymethyl)bi Examples include aralkyl-type phenolic resins such as phenol aralkyl resins and naphthol aralkyl resins synthesized from phenyl and the like; paraxylylene and / or metaxylylene-modified phenolic resins; melamine-modified phenolic resins; terpene-modified phenolic resins; dicyclopentadiene-type phenolic resins and dicyclopentadiene-type naphthol resins synthesized by copolymerization of the above phenolic compounds and dicyclopentadiene; cyclopentadiene-modified phenolic resins; polycyclic aromatic ring-modified phenolic resins; biphenyl-type phenolic resins; triphenylmethane-type phenolic resins obtained by condensation or co-condensation of the above phenolic compounds with aromatic aldehyde compounds such as benzaldehyde and salicylaldehyde under an acidic catalyst; and phenolic resins obtained by copolymerizing two or more of these. These phenolic curing agents may be used individually or in combination of two or more.

[0034] From the viewpoint of reflow resistance, at least one selected from the group consisting of aralkyl-type phenol resins, dicyclopentadiene-type phenol resins, triphenylmethane-type phenol resins, copolymerized phenol resins of benzaldehyde-type phenol resins and aralkyl-type phenol resins, and novolac-type phenol resins (these are referred to as "specific phenolic curing agents") is preferable. The specific phenolic curing agents may be used alone or in combination of two or more. In one embodiment, the phenolic curing agent preferably contains an aralkyl-type phenol resin. The aralkyl-type phenol resin may be used in combination with other phenolic curing agents. When the phenol resin contains an aralkyl-type phenol resin, the content of the aralkyl-type phenol resin may be 70% by mass or more, 80% by mass or more, or 90% by mass or more based on the total mass of the phenolic curing agent. The content of the aralkyl-type phenol resin may be 100% by mass or less based on the total mass of the phenolic curing agent.

[0035] As the phenolic curing agent, for example, commercially available products such as MEH-7851 (Meiwa Plastic Industries, Ltd., product name), XL-225, XLC (Mitsui Chemicals, Inc., product name), MEH-7800SS (Meiwa Plastic Industries, Ltd., product name), SN-170 (Nippon Steel Chemical & Material Co., Ltd., product name), SN-395 (Nippon Steel Chemical & Material Co., Ltd., product name), DPP (Nippon Petrochemicals Co., Ltd., product name), MEH-7500 (Meiwa Plastic Industries, Ltd., product name), HE-510 (Air Water Chemical Inc., product name), Tamanol 758, 759 (Arakawa Chemical Industries, Ltd., product name) can be used.

[0036] The hydroxyl equivalent of the phenolic curing agent is not particularly limited. From the viewpoint of the balance of various properties such as moldability, reflow resistance, and electrical reliability, it may be 70 g / eq to 1000 g / eq, or 80 g / eq to 500 g / eq. The hydroxyl equivalent of the phenolic curing agent may be, for example, a value measured by a method in accordance with JIS K 0070:1992.

[0037] When the phenol-based curing agent is solid, its softening point or melting point is not particularly limited. From the viewpoints of moldability and reflow resistance, it may be 40°C to 180°C, and from the viewpoint of handleability during production of the epoxy resin composition, it may be 50°C to 130°C. Further, the softening point or melting point of the phenol-based curing agent may be 50°C to 100°C, or 50°C to 75°C, from the viewpoint of improving fluidity, lowering the high-temperature elastic modulus of the cured product of the epoxy resin composition, and improving reflow resistance. The melting point or softening point of the curing agent is a value measured in the same manner as the melting point or softening point of the epoxy resin.

[0038] The equivalent ratio of the epoxy resin to the phenol-based curing agent, that is, the ratio of the number of hydroxyl groups in the phenol-based curing agent to the number of epoxy groups in the epoxy resin (number of hydroxyl groups in the phenol-based curing agent / number of epoxy groups in the epoxy resin) is not particularly limited. From the viewpoint of reducing the amount of unreacted components of each, the equivalent ratio of the epoxy resin to the phenol-based curing agent may be 0.5 to 2.0, or 0.6 to 1.3. From the viewpoints of moldability and reflow resistance, the equivalent ratio of the epoxy resin to the phenol-based curing agent may be 0.8 to 1.2.

[0039] The content of the curing agent can be appropriately selected depending on the combination of the curable resin and the curing agent, etc. When using an epoxy resin and a phenol-based curing agent, the content of the phenol-based curing agent may be 40 parts by mass to 250 parts by mass, 50 parts by mass to 200 parts by mass, 60 parts by mass to 170 parts by mass, 70 parts by mass to 140 parts by mass, or 80 parts by mass to 125 parts by mass relative to 100 parts by mass of the curable resin.

[0040] When using an epoxy resin and a phenol-based curing agent, curing agents other than phenol-based curing agents (such as acid anhydride-based curing agents, amine-based curing agents, imidazole-based curing agents, etc.) may be further used. The proportion of the phenol-based curing agent relative to the total amount of the curing agent is preferably 80% by mass or more, and more preferably 90% by mass or more.

[0041] Further, instead of the phenol-based curing agent, one or more types of curing agents other than phenol-based curing agents may be used.

[0042] The sealing resin composition may further contain a filler. Examples of fillers include inorganic fillers and organic fillers, but inorganic fillers are preferred from the viewpoint of suppressing degradation of the resin material due to radiation in outer space and heat resistance. In this specification, inorganic fillers do not include neutron absorbers. When an organic filler is used, the content of the organic filler is preferably 4.00% by mass or less, more preferably 1.00% by mass or less, based on the total mass of the sealing resin composition, and it is particularly preferable that the sealing resin composition does not contain an organic filler.

[0043] The material of the inorganic filler is not particularly limited. Examples of inorganic filler materials include fused silica, crystalline silica, glass, alumina, calcium carbonate, zirconium silicate, calcium silicate, silicon nitride, aluminum nitride, magnesium oxide, silicon carbide, beryllia, zirconia, zircon, fossilite, steatite, spinel, mullite, titania, talc, clay, mica, etc. In addition, inorganic fillers with flame retardant properties such as aluminum hydroxide, magnesium hydroxide, composite metal hydroxides such as magnesium-zinc composite hydroxides, and zinc borate may be used. From the viewpoint of reducing the coefficient of thermal expansion, silica such as fused silica is preferred, and from the viewpoint of high thermal conductivity, alumina is preferred.

[0044] The shape of the inorganic filler is not particularly limited, but a spherical shape is preferred from the viewpoint of filling properties and mold wear resistance.

[0045] The inorganic filler content is not particularly limited. From the viewpoint of further improving the properties of the cured product of the sealing resin composition, such as the coefficient of thermal expansion, thermal conductivity, and elastic modulus, the inorganic filler content may be 30% or more by volume, 40% or more by volume, 45% or more by volume, or 50% or more by volume of the total cured product of the sealing resin composition. From the viewpoint of improving fluidity and reducing viscosity, the inorganic filler content may be 98% or less by volume, or 97% or less by volume of the total cured product of the sealing resin composition. The inorganic filler content in the sealing resin composition can be appropriately adjusted so that the inorganic filler content in the cured product falls within the above numerical range.

[0046] Furthermore, for example, when the sealing resin composition is used for compression molding, the inorganic filler content may be 70% to 99% by volume, 80% to 99% by volume, 83% to 99% by volume, or 85% to 99% by volume of the total cured product of the sealing resin composition. The inorganic filler content in the sealing resin composition can be appropriately adjusted so that the inorganic filler content in the cured product falls within the above numerical range.

[0047] The inorganic filler content in the cured product of a sealing resin composition is measured as follows: First, the total mass of the cured product is measured. The cured product is then baked at 400°C for 2 hours, and then at 700°C for 3 hours to evaporate the resin components, and the mass of the remaining inorganic filler is measured. The volume is calculated from the obtained masses and their respective specific gravities, and the ratio of the volume of inorganic filler to the total volume of the cured product is obtained as the inorganic filler content.

[0048] The mass-based content of inorganic filler in the sealing resin composition may be 70% by mass or more, 80% by mass or more, or 85% by mass or more, and may also be 96% by mass or less, 95% by mass or less, or 94% by mass or less.

[0049] When the inorganic filler is particulate, its average particle size is not particularly limited. For example, the overall volume-average particle size of the inorganic filler may be 80 μm or less, 50 μm or less, 40 μm or less, 30 μm or less, 25 μm or less, 20 μm or less, or 15 μm or less. Alternatively, the overall volume-average particle size of the inorganic filler may be 0.1 μm or more, 0.2 μm or more, or 0.3 μm or more. When the volume-average particle size of the inorganic filler is 0.1 μm or more, the increase in viscosity of the sealing resin composition tends to be suppressed. When the volume-average particle size is 80 μm or less, the ability to fill narrow gaps tends to improve. The volume-average particle size of the inorganic filler can be measured as the particle size (D50) when the cumulative amount from the smallest diameter side reaches 50% in the volume-based particle size distribution measured by a laser scattering diffraction particle size distribution analyzer.

[0050] The encapsulating resin composition may further contain a triazine ring-containing compound. In the triazine ring-containing compound, the position of the nitrogen in the triazine ring is not particularly limited. That is, the triazine forming the backbone may be any of 1,2,3-triazine, 1,2,4-triazine, and 1,3,5-triazine. Among these, the triazine ring is preferably 1,3,5-triazine.

[0051] In triazine ring-containing compounds, the triazine ring is preferably substituted. In particular, the triazine ring-containing compound is preferably substituted with a primary amino group or a secondary amino group, and more preferably with a primary amino group. That is, the triazine ring-containing compound is preferably substituted with a primary amino group in which at least one of the hydrogen atoms bonded to the three carbon atoms on the triazine (C3H3N3) is substituted with a primary amino group. The substitution position of the monovalent group may be any of the three carbon atoms. The number of substitutions of the monovalent group may be one to three.

[0052] The molecular weight of the triazine ring-containing compound is not particularly limited and may be, for example, 100 to 800, 200 to 700, or 300 to 600.

[0053] The melting point of a triazine ring-containing compound is not particularly limited and may be, for example, 200°C or lower, 175°C or lower, or 150°C or lower, or 0°C or higher, 10°C or higher, or 25°C or higher. The melting point of a triazine ring-containing compound can be measured using a melting point meter or the like.

[0054] The content of the triazine ring-containing compound may be 0.3% by mass or more, 0.5% by mass or more, 1.0% by mass or more, 2.0% by mass or more, or 3.0% by mass or more, based on the total mass of the epoxy resin composition, and may also be 20.0% by mass or less, 17.5% by mass or less, 15.0% by mass or less, 12.5% ​​by mass or less, or 10.0% by mass or less.

[0055] In addition to the components described above, the sealing resin composition may also contain various additives such as curing accelerators, coupling agents, ion exchangers, mold release agents, flame retardants, colorants, and stress relievers. The epoxy resin composition may also contain various additives well known in the art, in addition to the additives exemplified below, as needed.

[0056] The type of curing accelerator is not particularly limited and can be selected according to the type of epoxy resin, the desired properties of the epoxy resin composition, etc. Examples of curing accelerators include diazabicycloalkenes such as 1,5-diazabicyclo[4.3.0]nonene-5 (DBN) and 1,8-diazabicyclo[5.4.0]undecene-7 (DBU); cyclic amidine compounds such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, and 2-heptadecylimidazole; derivatives of the cyclic amidine compounds; phenol novolac salts of the cyclic amidine compounds or their derivatives; and quinone compounds such as maleic anhydride, 1,4-benzoquinone, 2,5-tholquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, and phenyl-1,4-benzoquinone. Compounds having intramolecular polarization obtained by adding compounds with π bonds, such as zophenylmethane; cyclic amidinium compounds such as tetraphenylborate salt of DBU, tetraphenylborate salt of DBN, tetraphenylborate salt of 2-ethyl-4-methylimidazole, and tetraphenylborate salt of N-methylmorpholine; tertiary amine compounds such as pyridine, triethylamine, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol; derivatives of the above tertiary amine compounds; ammonium salt compounds such as tetra-n-butylammonium acetate, tetra-n-butylammonium phosphate, tetraethylammonium acetate, tetra-n-hexylammonium benzoate, and tetrapropylammonium hydroxide;Organic phosphines such as primary phosphines like ethylphosphine and phenylphosphine, secondary phosphines like dimethylphosphine and diphenylphosphine, triphenylphosphine, diphenyl(p-tolyl)phosphine, tris(alkylphenyl)phosphine, tris(alkoxyphenyl)phosphine, tris(alkyl-alkoxyphenyl)phosphine, tris(dialkylphenyl)phosphine, tris(trialkylphenyl)phosphine, tris(tetraalkylphenyl)phosphine, tris(dialkoxyphenyl)phosphine, tris(trialkoxyphenyl)phosphine, tris(tetraalkoxyphenyl)phosphine, trialkylphosphine, dialkylarylphosphine, alkyldiarylphosphine, trinaphthylphosphine, tris(benzyl)phosphine, and other tertiary phosphines; phosphine compounds such as complexes of the above organic phosphines with organoborons; and the above organic phosphines or the above phosphine compounds with maleic anhydride, 1,4-benzoquinone, 2,5-tholquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone. Compounds having intramolecular polarization obtained by adding compounds having π bonds, such as quinone compounds like 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, phenyl-1,4-benzoquinone, anthraquinone, and diazophenylmethane; and the organophosphine or the phosphine compound with 4-bromophenol, 3-bromophenol, 2-bromophenol, 4-chlorophenol, 3-chlorophenol, 2-chlorophenol, and 4-iodidepheno Compounds having intramolecular polarization obtained by reacting halogenated phenol compounds such as 3-iodidephenol, 2-iodidephenol, 4-bromo-2-methylphenol, 4-bromo-3-methylphenol, 4-bromo-2,6-dimethylphenol, 4-bromo-3,5-dimethylphenol, 4-bromo-2,6-di-t-butylphenol, 4-chloro-1-naphthol, 1-bromo-2-naphthol, 6-bromo-2-naphthol, and 4-bromo-4'-hydroxybiphenyl, followed by a dehalogenation step;Examples include tetrasubstituted phosphonium compounds such as tetraphenylphosphonium, tetraphenylborate salts of tetrasubstituted phosphoniums such as tetraphenylphosphonium tetra-p-tolylborate, and salts of tetrasubstituted phosphonium with phenolic compounds; phosphobetaine compounds; and adducts of phosphonium compounds with silane compounds. The curing accelerator may be used alone or in combination of two or more types.

[0057] Particularly suitable curing accelerators when epoxy resin is used as the curable resin include triphenylphosphine, and adducts of triphenylphosphine and quinone compounds.

[0058] The curing accelerator content may be 0.1 to 10 parts by mass, 1 to 5 parts by mass, or 1 to 3 parts by mass per 100 parts by mass of the resin component (i.e., the total of the curable resin and the curing agent). When the amount of curing accelerator is 0.1 parts by mass or more per 100 parts by mass of the resin component, it tends to cure well in a short time. When the amount of curing accelerator is 10 parts by mass or less per 100 parts by mass of the resin component, it tends to result in a good molded product with a curing speed that is not too fast.

[0059] If the encapsulating resin composition contains an inorganic filler, a coupling agent may be included to enhance the adhesion between the resin component and the inorganic filler. In this disclosure, triazine ring-containing compounds are not included as coupling agents. Examples of coupling agents include silane compounds such as epoxysilane, mercaptosilane, aminosilane, alkylsilane, ureidosilane, and vinylsilane, as well as titanium compounds, aluminum chelate compounds, and aluminum / zirconium compounds. From the viewpoint of ease of handling, it is preferable that the encapsulating resin composition contains anilinosilane.

[0060] The amount of coupling agent is preferably 0.05 to 5 parts by mass, and more preferably 0.1 to 2.5 parts by mass, per 100 parts by mass of inorganic filler. When the amount of coupling agent is 0.05 parts by mass or more per 100 parts by mass of inorganic filler, the adhesion to the frame tends to improve further. When the amount of coupling agent is 5 parts by mass or less per 100 parts by mass of inorganic filler, the moldability of the package tends to improve further.

[0061] From the viewpoint of adhesion between the resin component and the inorganic filler, it is preferable that the sealing resin composition contains a silane coupling agent. Generally, silane coupling agents tend to adsorb moisture, and depending on the type and content of the silane coupling agent, this may cause an increase in water absorption. On the other hand, it has been found that the sealing resin composition of this disclosure has excellent moisture-absorbing curing properties even when it contains a silane coupling agent. From this viewpoint, the content of the silane coupling agent may be 2.0% by mass or more, 3.0% by mass or more, or 3.5% by mass or more, or 10.0% by mass or less, 8.0% by mass or less, or 6.0% by mass or less, based on the total mass of the resin component (for example, the total mass of the epoxy resin and the phenolic curing agent).

[0062] The encapsulating resin composition may contain an ion exchanger from the viewpoint of improving the moisture resistance and high-temperature storage characteristics of the electronic component device comprising the element to be encapsulated. The ion exchanger is not particularly limited, and conventionally known ones can be used. Specifically, examples include hydrotalcite compounds and hydrated oxides of at least one element selected from the group consisting of magnesium, aluminum, titanium, zirconium, and bismuth. The ion exchanger may be used alone or in combination of two or more.

[0063] The amount of ion exchanger contained is not particularly limited, as long as it is sufficient to capture ions such as halogen ions. For example, it may be 0.1 to 30 parts by mass, or 1 to 15 parts by mass, per 100 parts by mass of resin component.

[0064] The sealing resin composition may contain a release agent from the viewpoint of obtaining good release properties from the mold during molding. The release agent is not particularly limited, and conventionally known ones can be used. Specifically, examples include carnauba wax, higher fatty acids such as montanic acid and stearic acid, higher fatty acid metal salts, ester waxes such as montanic acid esters, and polyolefin waxes such as oxidized polyethylene and non-oxidized polyethylene. The release agent may be used alone or in combination of two or more types.

[0065] The release agent content may be 0.01 to 15 parts by mass, or 0.1 to 10 parts by mass, per 100 parts by mass of the resin component. When the amount of release agent is 0.01 parts by mass or more per 100 parts by mass of the resin component, sufficient release properties tend to be obtained. When it is 15 parts by mass or less, better adhesion tends to be obtained.

[0066] The sealing resin composition may contain a flame retardant. The flame retardant is not particularly limited, and conventionally known ones can be used. Specifically, examples include organic or inorganic compounds containing halogen atoms, antimony atoms, nitrogen atoms, or phosphorus atoms, and metal hydroxides. The flame retardant may be used alone or in combination of two or more types.

[0067] The amount of flame retardant is not particularly limited as long as it is sufficient to obtain the desired flame retardant effect. For example, it may be 1 to 300 parts by mass, or 2 to 150 parts by mass, per 100 parts by mass of resin component.

[0068] The encapsulating resin composition may further contain a coloring agent. Examples of known coloring agents include carbon black, organic dyes, organic pigments, titanium dioxide, red lead, and red iron oxide. The amount of coloring agent can be appropriately selected depending on the purpose. One coloring agent may be used alone, or two or more may be used in combination.

[0069] The sealing resin composition may contain stress-relieving agents such as silicone oil and silicone rubber particles. Including stress-relieving agents can further reduce package warping and the occurrence of package cracks. Examples of commonly used stress-relieving agents (flexible agents) include thermoplastic elastomers such as silicone, styrene, olefin, urethane, polyester, polyether, polyamide, and polybutadiene; rubber particles such as NR (natural rubber), NBR (acrylonitrile-butadiene rubber), acrylic rubber, urethane rubber, and silicone powder; and rubber particles having a core-shell structure such as methyl methacrylate-styrene-butadiene copolymer (MBS), methyl methacrylate-silicone copolymer, and methyl methacrylate-butyl acrylate copolymer. One type of stress-relieving agent may be used alone, or two or more types may be used in combination. Among these, silicone-based stress-relieving agents are preferred. Examples of silicone-based stress-relieving agents include those having epoxy groups, those having amino groups, and those modified with polyether.

[0070] The method for preparing the encapsulating resin composition is not particularly limited. A common method involves thoroughly mixing predetermined amounts of components using a mixer or the like, then melt-kneading them using a mixing roll, extruder, or the like, followed by cooling and pulverization. More specifically, for example, a method can be used in which predetermined amounts of the above-mentioned components are uniformly stirred and mixed, then kneaded using a kneader, roll, extruder, or the like that has been preheated to 70°C to 140°C, followed by cooling and pulverization.

[0071] The sealing resin composition may be solid or liquid. When the sealing resin composition is solid, it may be in powder, granular, or tablet form. From the viewpoint of ease of handling, it is preferable that the sealing resin composition is solid at room temperature and pressure (for example, 25°C and atmospheric pressure). Furthermore, when the sealing resin composition is in tablet form, it is preferable from the viewpoint of ease of handling that its dimensions and mass are such that they match the molding conditions of the package.

[0072] [Electronic component device] An electronic component device according to one aspect of the present disclosure comprises an element and a cured product of the sealing resin composition according to the above embodiment for sealing the element.

[0073] Examples of electronic component devices include those in which elements (active elements such as semiconductor chips, transistors, diodes, and thyristors, and passive elements such as capacitors, resistors, and coils) are mounted on support members such as lead frames, pre-wired tape carriers, wiring boards, glass, silicon wafers, and organic substrates, and the resulting element section is sealed with a sealing resin composition. More specifically, DIP (Dual Inline Package), PLCC (Plastic Leaded Chip Carrier), QFP (Quad Flat Package), SOP (Small Outline Package), SOJ (Small Outline J-lead package), TSOP (Thin Small Outline Package), TQFP (Thin Quad Flat) have a structure in which elements are fixed on a lead frame, the terminal parts of the elements such as bonding pads and the lead parts are connected by wire bonding, bumps, etc., and then sealed by transfer molding, etc. using a sealing resin composition. Examples include general resin-encapsulated ICs such as Packages; TCPs (Tape Carrier Packages) having a structure in which elements connected to a tape carrier with bumps are encapsulated with an encapsulating resin composition; COB (Chip On Board) modules, hybrid ICs, multi-chip modules, etc., having a structure in which elements connected to wiring formed on a support member by wire bonding, flip-chip bonding, solder, etc., are encapsulated with an encapsulating resin composition; and BGAs (Ball Grid Arrays), CSPs (Chip Size Packages), MCPs (Multi Chip Packages), etc., having a structure in which elements are mounted on the surface of a support member having terminals for wiring board connection formed on the back surface, the elements are connected to the wiring formed on the support member by bumps or wire bonding, and then the elements are encapsulated with an encapsulating resin composition. Furthermore, the sealing resin composition can also be suitably used in printed circuit boards.

[0074] Methods for sealing electronic components using a sealing resin composition include low-pressure transfer molding, injection molding, and compression molding.

[0075] The sealing resin composition according to the above embodiment can exhibit excellent soft error suppression effects even in outer space where the amount of neutron radiation (amount of radiation per unit time) is high, and is suitable for use as a sealing material for electronic component devices mounted on spacecraft. In this disclosure, "spacecraft" is a general term for artificial objects used in outer space, and includes, for example, artificial satellites, space stations, probes, space telescopes, and manned spacecraft.

[0076] [Method for Manufacturing Electronic Component Devices] A method for manufacturing electronic component devices according to one aspect of the present disclosure includes sealing elements with the sealing resin composition according to the above embodiment. The method for sealing elements is not particularly limited and includes the molding method described above.

[0077] The present disclosure will be described in more detail below with reference to examples, but the present disclosure is not limited to the following examples.

[0078] [Examples 1-15, Comparative Examples 1-6] Gadolinium oxide (Gd) as a neutron absorber ２ O ３ ), samarium oxide (Sm ２ O ３ A encapsulating resin composition was prepared using either ) or BN. The content (volume %) of the neutron absorber in each encapsulating resin composition is shown in Table 1. The types and content of components other than the neutron absorber (content when the total of components excluding the neutron absorber is taken as 100% by mass) are the same as those for CEL-9221HF (manufactured by Resonaq Corporation, trade name; encapsulating resin composition containing epoxy resin, phenolic curing agent, phosphorus curing accelerator, and inorganic filler).

[0079] [Evaluation of Soft Error Suppression Effect] The soft error suppression effect of the encapsulating resin compositions of Examples 1 to 15 and Comparative Examples 1 to 6 was evaluated using the following procedure. This evaluation method included the following steps S1 to S6. (Step S1) A structural model is generated representing an electronic component comprising an encapsulating material containing a plurality of particles capable of absorbing cosmic rays, and a transistor protected by the encapsulating material. In the structural model, an encapsulating material layer representing the encapsulating material is laminated above a transistor layer representing the transistor. (Step S2) A cosmic ray simulation is performed in which the plurality of cosmic rays are virtually irradiated onto the structural model so that they pass through the encapsulating material layer and the transistor layer in that order. (Step S3) A first profile is generated based on data showing the cosmic rays absorbed by the transistor in the structural model in the cosmic ray simulation. The first profile shows the number of events per unit time, which is the number of times a cosmic ray with a given energy value is absorbed by the transistor, for each of the plurality of energy values ​​that constitute the energy distribution of the cosmic rays. (Step S4) Each of the plurality of energy values ​​is converted into a charge quantity, and the first profile is converted into a second profile showing the number of events for each of the plurality of charge quantities. (Step S5) Perform a circuit simulation that repeatedly compares the forward current from the transistor based on the transistor specifications with the error current determined based on the second profile. (Step S6) In the circuit simulation, if the error current is greater than or equal to the forward current, it is identified as a soft error.

[0080] According to this evaluation method, a cosmic ray simulation is performed on a structural model representing an electronic component comprising a encapsulant and a transistor, virtually irradiating it with cosmic rays. This generates a first profile showing the relationship between the energy distribution of cosmic rays and the number of events. Subsequently, this first profile is converted into a second profile showing the relationship between the distribution of charge affecting the transistor and the number of events. Then, soft errors are identified based on the transistor specifications and the results of a circuit simulation based on the second profile. In this way, by identifying soft errors in electronic components with encapsulants while considering the energy distribution of cosmic rays, soft errors can be determined with greater accuracy. In addition, it becomes possible to evaluate the performance of the encapsulant in absorbing cosmic rays.

[0081] (Structural Model) Figure 1 shows a structural model according to an embodiment. In the embodiment, a structural model 100 was created in which a substrate layer 110, an insulating layer 120, a metal layer 130, and a sealing material layer 140 are arranged in this order from bottom to top. The substrate layer 110 was set assuming a silicon substrate, the insulating layer 120 was set assuming silicon dioxide (SiO2), and the metal layer 130 was set assuming copper (Cu) wiring. For the sealing material layer 140, Gd was added to the bisphenol A type epoxy resin. ２ O ３ Sm ２ O ３ Alternatively, we considered a encapsulating material in which one type of particle (neutron absorber) selected from BN is scattered.

[0082] The overall dimensions of the structural model 100 were set to width (W), depth (D), and height (H) of 1000 μm, 1000 μm, and 1503.35 μm, respectively. The heights of the substrate layer 110, insulating layer 120, metal layer 130, and sealing layer 140 were set to 489.75 μm, 0.35 μm, 3 μm, and 1000 μm, respectively.

[0083] A transistor layer 150 was set in the region spanning the substrate layer 110 and the insulating layer 120. Silicon was assumed to be the material for each transistor. A sensitive region 151 representing a single transistor was represented by a three-dimensional object that exhibits an inverted T-shape when viewed from the side. As shown in the enlarged view in Figure 1, this inverted T-shaped three-dimensional object is formed by placing an upper rectangular parallelepiped, smaller than the lower rectangular parallelepiped, in the center of the upper surface of the lower rectangular parallelepiped. The dimensions of the lower rectangular parallelepiped were set to 0.2625 μm, 0.147 μm, and 0.5 μm in width, depth, and height, respectively. The dimensions of the upper rectangular parallelepiped were set to 0.175 μm, 0.098 μm, and 0.25 μm in width, depth, and height, respectively. A single sensitive region 151 was positioned so as to be embedded in the upper center of a virtual block whose width, depth, and height were 20 μm, 10 μm, and 10.25 μm, respectively. Then, the transistor layer 150 was set up by arranging these virtual blocks horizontally in a two-dimensional manner in the region spanning the substrate layer 110 and the insulating layer 120. The transistor layer 150 was positioned within the structural model 100 such that the boundary between the upper rectangular parallelepiped and the lower rectangular parallelepiped coincided with the boundary between the substrate layer 110 and the insulating layer 120.

[0084] To set the particle concentration in the encapsulant, a method was introduced to arrange the particles within the encapsulant layer 140 to satisfy a specified concentration. Figure 2 shows this method. In this method, a cube 141 containing four particles 142 with a diameter of 10 μm was used as the constituent unit of the encapsulant layer 140. The length of one side of the cube 141 could be changed between 20 μm and 100 μm. In state ST1 shown in Figure 2, the length of one side of the cube 141 is 20 μm, and in state ST2, the length is 100 μm. The larger the dimensions of the cube 141, the lower the particle concentration in the encapsulant.

[0085] The arrangement of the four particles 142 within the cube 141 is as follows. Two particles 142 are arranged near the lower surface of the cube 141 along one diagonal of a virtual cross-section obtained by virtually cutting the cube 141 along the horizontal direction. Further, the remaining two particles 142 are arranged near the upper surface of the cube 141 along the other diagonal of the virtual cross-section. Each particle 142 is arranged within the cube 141 such that the distance between particles 142 increases as the size of the cube 141 increases.

[0086] (Cosmic ray simulation) Cosmic ray simulation using the structural model 100 was performed under conditions assuming the International Space Station (ISS) located at an altitude of 400 km. To perform this cosmic ray simulation, PHITS (Particle and Heavy Ion Transport code System) was used. PHITS is a Monte Carlo calculation code that simulates various radiation behaviors in materials using nuclear reaction models, nuclear data, and the like. In the cosmic ray simulation, a plurality of cosmic rays each having a nucleus of 1H, 4He, 7Li, 9Be, 11B, 12C, 14N, 16O, 20Ne, 24Mg, 28Si, and 56Fe were virtually irradiated from above the structural model 100. As the energy region of cosmic rays, 10 －７ to 10 ３ MeV was set, and while randomly determining the energy value of cosmic rays within this energy region, the process of irradiating 10,000 cosmic rays onto the structural model 100 was repeated 10030 times.

[0087] (Generation of first profile) The number of cosmic rays absorbed in one second by 3200 sensitive regions 151 (transistors) located in the central part of the transistor layer 150 was acquired as the number of events. Further, the energy values of individual cosmic rays absorbed by the 3200 sensitive regions 151 were acquired. Using these acquired data, a first profile showing the number of events for each of a plurality of energy values was generated.

[0088] (Conversion to the second profile) The generated first profile was converted to a second profile that shows the number of events for each of several charge quantities. For this conversion, a conversion constant obtained by the following formula was used: (Conversion constant) = (Elementary charge) / (Energy value required to generate an e-h pair) As mentioned above, silicon was assumed to be the material of the transistor, so the conversion constant was 1.6 × 10⁻¹⁹ [C] / 3.6 [eV] = 44.5 [fC / MeV]. Each energy value shown in the first profile was converted to a charge quantity by multiplying it by the conversion constant, thereby converting the first profile to the second profile.

[0089] (Circuit Simulation) As a circuit simulation, the operation of a count-up circuit was simulated. For the circuit simulation, the specifications of the transistor were set as the design values ​​of the MOSFET: channel width, channel length, mobility, gate oxide capacitance, and threshold voltage. For the D-type flip-flop, the interval and frequency of the square wave, the frequency of the clock signal, and the delay time of the input signal and the clock signal were set. Furthermore, as semiconductor properties, the operating temperature, band gap, and doping level were set based on the Boltzmann distribution. In the circuit simulation, forward current was repeatedly output from the transistor at predetermined time intervals based on these settings.

[0090] The second profile obtained by converting the first profile shows the total for 3200 transistors. By dividing the number of events corresponding to each charge amount shown in the second profile by 3200, a second profile for one transistor was obtained as a unit second profile. Using this unit second profile, error currents were repeatedly generated in synchronization with the forward current. Each error current is a minute current obtained by dividing a randomly selected charge amount from the unit second profile by a predetermined minute time. Here, "predetermined" means that any minute time can be set.

[0091] (Identification of Soft Errors) In the circuit simulation, the forward current and error current generated simultaneously were compared, and a soft error was identified when the error current was greater than or equal to the forward current. This comparison was repeated to obtain the number of soft errors that occurred per second. Furthermore, the number of soft errors that occurred per second was converted to the number per 10⁹ hours, and this converted value was obtained as the soft error rate.

[0092] Gd ２ O ３ Sm ２ O ３ For each of the above procedures, and BN, by repeatedly performing the above series of steps while changing the particle concentration (mass %), we were able to verify the range of concentrations that control or reduce the effects of cosmic rays on electronic components. The results obtained are shown in Table 1. Here, "relative error rate" is the ratio of these particles (Gd ２ O ３ Sm ２ O ３ This refers to the ratio (C / C0) of the soft error rate C when particles are present to the soft error rate C0 when particles are not present (and BN).

[0093]

[0094] 100...Structural model, 110...Substrate layer, 120...Insulating layer, 130...Metal layer, 140...Sealing layer, 141...Cube, 142...Particle, 150...Transistor layer, 151...Sensible region.

Claims

1. A sealing resin composition comprising a curable resin and a neutron absorbent, wherein the content of the neutron absorbent is 0.3% by mass to 24% by mass, based on the total mass of the sealing resin composition.

2. The encapsulating resin composition according to claim 1, wherein the neutron absorbing material comprises at least one element selected from samarium, gadolinium, and boron.

3. The encapsulating resin composition according to claim 1, wherein the neutron absorbing material is at least one selected from samarium oxide, gadolinium oxide, and boron nitride.

4. The encapsulating resin composition according to claim 1, wherein the curable resin is an epoxy resin, and further contains a phenolic curing agent and an inorganic filler.

5. The sealing resin composition according to claim 1, used in electronic component devices mounted on spacecraft.

6. An electronic component device comprising an element and a cured product of a sealing resin composition according to any one of claims 1 to 5 for sealing the element.

7. A method for manufacturing an electronic component device, comprising sealing an element with the sealing resin composition described in any one of claims 1 to 5.

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