Liquid sealing agent, electronic component and method for producing same, and semiconductor device

Abstract

The present invention provides a liquid sealing agent which has good curability and is capable of suppressing molding failure.　The present invention provides a liquid sealing agent which contains an epoxy resin, a curing agent, a curing catalyst and a filler, while having a gel time of 100 seconds to 620 seconds at 120°C.

Description

Liquid sealant, electronic component and manufacturing method thereof, and semiconductor device

[0001] The present disclosure relates to a liquid sealant, an electronic component and a method for manufacturing the same, and a semiconductor device.

[0002] A semiconductor element, which is one of the components constituting a semiconductor device such as a smartphone or a mobile personal computer, is fixed on a support such as a substrate. A method of using an encapsulant is known for the purpose of improving the moisture resistance, heat resistance, and reliability against external stress of the semiconductor element.

[0003] In recent years, there has been a growing demand for smaller and thinner semiconductor devices. Accordingly, improvements have been made to semiconductor element packaging methods. One of these improvements is the improvement of packaging methods. Conventionally, packages are fabricated using individual semiconductor elements. This method results in a package that is larger than the chip. For this reason, conventional packaging methods are not suitable for large semiconductor devices. Therefore, a technology called wafer-level chip-size packaging technology is used, which packages the semiconductor element at the wafer level after circuit formation is complete and before it is cut into chips.

[0004] To use wafer-level chip-size packaging technology, the encapsulation method must also be improved. Compression molding is known as an encapsulation method suitable for this technology. In compression molding, an encapsulant is injected into the cavity below the semiconductor element. The encapsulant is then cured.

[0005] Conventionally, solid resin compositions such as granular resin compositions have been widely used as curable resin compositions for encapsulating semiconductor elements by compression molding. However, with the development of new compression molding techniques, liquid curable resin compositions (i.e., liquid encapsulants) are also increasingly being used.

[0006] As a liquid sealant, a composition containing a liquid epoxy resin has been proposed from the viewpoint of a balance of various properties such as electrical properties, moisture resistance, heat resistance, mechanical properties, and adhesive properties (see, for example, Patent Documents 1 and 2).

[0007] International Publication No. 2018 / 221681 Pamphlet Japanese Patent Application Laid-Open No. 2015-105304

[0008] Liquid sealants are required to have the property of curing within a limited time. Therefore, compositions with a relatively high viscosity increase ratio are used as liquid sealants. However, when a liquid sealant with a high viscosity increase ratio is used for compression molding, the liquid sealant may cure before reaching the desired sealing position before curing. In this case, areas that cannot be sealed may be generated.

[0009] On the other hand, if a liquid sealant designed to have a long curing time is used to prevent the occurrence of unsealed areas, the liquid sealant may not be cured completely by the end of compression molding, which can cause molding defects due to the liquid sealant adhering to the release film.

[0010] The present disclosure aims to provide a liquid sealant that has good curing properties and can suppress molding defects. It also aims to provide an electronic component having a cured product of the liquid sealant, a method for producing the same, and a semiconductor device having the electronic component.

[0011] To achieve the above object, the liquid sealant according to this embodiment contains an epoxy resin, a curing agent, a curing catalyst, and a filler, and has a gel time of 100 to 620 seconds at 120°C.

[0012] According to this embodiment, it is possible to provide a liquid sealant that has good curing properties and can suppress molding defects.

[0013] (Liquid Sealant) The liquid sealant according to this embodiment contains an epoxy resin, a curing agent, a curing catalyst, and a filler. This liquid sealant may further contain other components as necessary. The liquid sealant is used for sealing by compression molding. This liquid sealant is sometimes called a "liquid compression molding material (LCM (Luquid Compression Molding) material)."

[0014] <Epoxy Resin> The epoxy resin is not limited to a specific resin as long as it is one of various epoxy resins generally used for semiconductor encapsulation. The epoxy resin to be used can be appropriately selected depending on the purpose. Examples of epoxy resins include aliphatic epoxy resins and aromatic epoxy resins.

[0015] <<Aliphatic Epoxy Resin>> The aliphatic epoxy resin contained in the liquid sealant imparts flexibility to the cured product of the liquid sealant. Examples of aliphatic epoxy resins include monofunctional aliphatic epoxy resins, difunctional aliphatic epoxy resins, and polyfunctional aliphatic epoxy resins. Of these aliphatic epoxy resins, one may be used alone. Alternatively, two or more aliphatic epoxy resins may be used in combination.

[0016] Monofunctional aliphatic epoxy resins are compounds having one epoxy group per molecule. Examples of monofunctional aliphatic epoxy resins include alkyl alcohol glycidyl ethers such as butyl glycidyl ether and 2-ethylhexyl glycidyl ether; and alkenyl alcohol glycidyl ethers such as vinyl glycidyl ether and allyl glycidyl ether.

[0017] A difunctional aliphatic epoxy resin is a compound having two epoxy groups in one molecule. Examples of difunctional aliphatic epoxy resins include alkylene glycol diglycidyl ether, poly(alkylene glycol) diglycidyl ether, and alkenylene glycol diglycidyl ether.

[0018] A polyfunctional aliphatic epoxy resin is a compound having three or more epoxy groups in one molecule. Examples of polyfunctional aliphatic epoxy resins include trimethylolpropane triglycidyl ether, pentaerythritol (tri- or tetra-)glycidyl ether, and dipentaerythritol (tri-, tetra-, penta-, or hexa-)glycidyl ether. These ethers are polyglycidyl ethers of trifunctional or higher alcohols such as trimethylolpropane, pentaerythritol, or dipentaerythritol.

[0019] Among these, from the viewpoint of reliability (thermal cycle resistance), difunctional or trifunctional aliphatic epoxy resins are preferred, and resins represented by the following general formula (1) are more preferred.

[0020] In the general formula (1), n ​​is a natural number from 1 to 15.

[0021] The number average molecular weight of the aliphatic epoxy resin is not limited to a specific molecular weight. An appropriate number average molecular weight can be selected depending on the purpose. From the viewpoint of imparting flexibility to the cured product of the liquid sealant, the number average molecular weight is preferably in the range of 200 to 2,000. The number average molecular weight of the aliphatic epoxy resin can be measured by a general method for measuring number average molecular weight.

[0022] The aliphatic epoxy resin used in this embodiment can be synthesized. However, commercially available aliphatic epoxy resins may also be used. Examples of commercially available products include Epogosee PT (general grade) (manufactured by Yokkaichi Synthetic Co., Ltd.), SR-8EGS (manufactured by Sakamoto Pharmaceutical Industry Co., Ltd.), and PG-207GS (manufactured by Nippon Steel Chemical & Material Co., Ltd.).

[0023] <<Aromatic Epoxy Resin>> Examples of aromatic epoxy resins include glycidyl ethers of phenols, glycidyl ether esters of hydroxycarboxylic acids, monoglycidyl esters or polyglycidyl esters of carboxylic acids, glycidylamine-type epoxy compounds, epoxy compounds having a naphthalene skeleton, and novolac compounds. Of these aromatic epoxy resins, one may be used alone. Alternatively, two or more aromatic epoxy resins may be used in combination.

[0024] Examples of glycidyl ethers of phenols include bisphenol A, bisphenol F, bisphenol AD, bisphenol S, catechol, and resorcinol.

[0025] Examples of glycidyl ether esters of hydroxycarboxylic acids include p-hydroxybenzoic acid.

[0026] Examples of mono- and polyglycidyl esters of carboxylic acids include the glycidyl esters of benzoic acid, phthalic acid, and terephthalic acid.

[0027] Examples of the glycidylamine type epoxy compound include diglycidylaniline, diglycidyltoluidine, triglycidyl-p-aminophenol, and tetraglycidyl-m-xylylenediamine.

[0028] Examples of epoxy compounds having a naphthalene skeleton include glycidyl esters of naphthol and glycidyl ether esters of β-hydroxynaphthoic acid.

[0029] Examples of novolak compounds include compounds obtained by novolakizing phenols such as phenol, catechol, and resorcinol.

[0030] Among these epoxy resins mentioned above, a preferred epoxy resin is a mixture of an aliphatic epoxy resin and an aromatic epoxy resin, in that it improves the curing properties while maintaining the hardness of the cured product of the liquid sealant.

[0031] The blending ratio (mass ratio) of the aliphatic epoxy resin to the aromatic epoxy resin in the mixture is not limited to a specific mass ratio. The mass ratio can be appropriately selected depending on the purpose. When the mixture has a preferred mass ratio of the aliphatic epoxy resin to the aromatic epoxy resin, the content of the aliphatic epoxy resin is 20% to 40% by mass. The content of the aromatic epoxy resin is 60% to 80% by mass.

[0032] The type and content of epoxy resin contained in a liquid sealant can be measured by the following method. First, the cured liquid sealant is thermally decomposed. Qualitative analysis is performed by gas chromatography mass spectrometry (GC-MS) of the decomposition product. From the peak areas of each component obtained by this analysis, the content of epoxy resin can be measured by the absolute calibration curve method.

[0033] <Curing Agent> The curing agent is not limited to a specific curing agent as long as it can cure the epoxy resin. An appropriate curing agent can be selected depending on the purpose. Examples of the curing agent include an amine-based curing agent containing an amine, an acid anhydride-based curing agent containing an acid anhydride, and a phenol-based curing agent containing a phenol. One of these curing agents can be used alone. Alternatively, two or more curing agents can be used in combination.

[0034] The content of the curing agent is preferably 1.0 to 20.0% by mass, and more preferably 1.0 to 9.0% by mass, based on the remaining components of the liquid sealant excluding the filler.

[0035] The content of the curing agent contained in the liquid sealant can be measured by the following method. First, the cured liquid sealant is thermally decomposed. Qualitative analysis is performed by measuring the decomposition product using gas chromatography-mass spectrometry (GC-MS). From the peak areas of each component obtained by this analysis, the content of the curing agent can be measured using the absolute calibration curve method.

[0036] <Curing catalyst> The curing catalyst is not limited to a specific curing catalyst as long as it is a curing catalyst generally used in resin compositions. A curing catalyst can be appropriately selected depending on the purpose. From the viewpoint of reactivity, a preferred curing catalyst is a heterocyclic compound containing a nitrogen atom. A heterocyclic compound containing a nitrogen atom refers to a compound containing a nitrogen atom as a constituent atom of the heterocycle.

[0037] Examples of heterocyclic compounds containing a nitrogen atom include imidazoles such as 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2,4-diamino-6-[2'-methylimidazolyl-(1')]ethyl-s-triazine, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, and 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole; Examples of suitable amines include undecene (DBU), DBU-phenol salt, DBU-octylate salt, DBU-p-toluenesulfonate, DBU-formate, DBU-orthophthalate, DBU-phenol novolac resin salt, DBU-based tetraphenylborate salt, diazabicyclononene (DBN), DBN-phenol novolac resin salt, diazabicyclooctane, pyrazole, oxazole, thiazole, imidazoline, pyrazine, morpholine, thiazine, indole, isoindole, benzimidazole, purine, quinoline, isoquinoline, quinoxaline, cinnoline, and pteridine. Among these, (2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2-ethyl-4-methylimidazole, and 2-phenyl-4-methyl-5-hydroxymethylimidazole are preferred from the viewpoint of reactivity.

[0038] The curing catalyst used in this embodiment can be synthesized. However, commercially available curing catalysts may also be used. Examples of commercially available curing catalysts include 2MZA (2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, manufactured by Shikoku Chemical Industry Corporation), 2E4MZ (2-ethyl-4-methylimidazole, manufactured by Shikoku Chemical Industry Corporation), and 2P4MHZ (2-phenyl-4-methyl-5-hydroxymethylimidazole, manufactured by Shikoku Chemical Industry Corporation).

[0039] The content of the curing catalyst is not limited to a specific content. The content of the curing catalyst can be selected appropriately depending on the purpose. The content of the curing catalyst is preferably 1.0% by mass to 12.0% by mass, more preferably 2.0% by mass to 7.0% by mass, and even more preferably 3.0% by mass to 7.0% by mass, relative to the epoxy resin. If the content exceeds 12.0% by mass, the improved curing properties may significantly shorten the product life. Alternatively, the liquid sealant may not spread throughout the entire surface during compression molding, resulting in insufficient filling of the liquid sealant. In these cases, the liquid sealant does not fully function. On the other hand, if the content of the curing catalyst is less than 1.0% by mass, the reduced curing properties may cause the liquid sealant to adhere to the release film. This may result in molding defects.

[0040] The content of the curing catalyst contained in the liquid sealant can be measured by the following method. First, the cured liquid sealant is thermally decomposed. Qualitative analysis is performed by gas chromatography mass spectrometry (GC-MS) of the decomposition product. The content of the curing catalyst can be measured by the absolute calibration curve method from the peak areas of each component obtained by this analysis.

[0041] The content of the curing catalyst is preferably adjusted depending on the type thereof. For example, the content of 2-ethyl-4-methylimidazole is preferably 1.0% by mass to 7.0% by mass relative to the epoxy resin. The content of 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine is preferably 1.5% by mass to 10.0% by mass relative to the epoxy resin. The content of 2-phenyl-4-methyl-5-hydroxymethylimidazole is preferably 2.0% by mass to 12.0% by mass relative to the epoxy resin.

[0042] <Filler> A filler is contained in the liquid sealant to adjust the properties of the cured product (mainly the linear expansion coefficient, elastic modulus, and water absorption) of the liquid sealant. The filler used in this embodiment is not limited to a specific filler. A filler can be appropriately selected depending on the purpose. Examples of this filler include silica such as fused silica and crystalline silica; calcium carbonate, clay, alumina, silicon nitride, silicon carbide, boron nitride, calcium silicate, potassium titanate, aluminum nitride, beryllia, zirconia, zircon, fosterite, steatite, spinel, mullite, titania, aluminum hydroxide, magnesium hydroxide, zinc borate, and zinc molybdate. One of these fillers can be used alone. Alternatively, two or more fillers can be used in combination. Among these, silica filler is preferred because it allows for a high loading amount. Furthermore, alumina filler is preferred because of its high thermal conductivity.

[0043] The filler may be a surface-treated filler. The surface treatment agent is not limited to a specific treatment agent. A surface treatment agent can be appropriately selected depending on the purpose. An example of the surface treatment agent is a silane coupling agent.

[0044] The silane coupling agent used is not limited to a specific silane coupling agent. A silane coupling agent can be appropriately selected depending on the purpose. Examples of silane coupling agents include epoxy-based, methacrylic-based, amino-based, vinyl-based, glycidoxy-based, and mercapto-based silane coupling agents.

[0045] The volume average particle size of the filler is not limited to a specific value. A volume average particle size can be selected appropriately depending on the purpose. A preferred volume average particle size is 0.05 μm to 10 μm. The preferred volume average particle size range depends on the type of filler. For example, a preferred volume average particle size of a silica filler is 10 nm to 5.0 μm. A preferred volume average particle size of an alumina filler is 0.1 μm to 5.0 μm. When using a silica filler, from the viewpoint of reducing viscosity, a filler having a volume average particle size of 10 nm to 100 nm is preferably used in combination with a filler having a volume average particle size of 0.1 μm to 5.0 μm. In this embodiment, the particle size corresponding to 50% of the volume cumulative particle size distribution measured using a laser diffraction method is defined as the volume average particle size.

[0046] The shape of the filler is not limited to a specific shape. Any shape can be selected depending on the purpose. Examples of filler shapes include spherical, irregular, and flaky shapes.

[0047] The content of the filler is preferably 30% by mass to 80% by mass, and more preferably 40% by mass to 75% by mass, based on the total mass of the liquid sealant.

[0048] The filler content in the liquid sealant can be measured by the following method. First, a cured liquid sealant is weighed into a crucible. The weighed cured liquid is heated to 850°C at a rate of 20°C / min. The crucible is then held at this temperature for 30 minutes. After cooling, the residue (ignition residue) remaining in the crucible is weighed. The amount of the ignition residue obtained is considered to be the amount of filler, and the filler content is calculated.

[0049] <Other Components> The other components are not limited to specific components as long as they are components commonly used in sealants. Other components can be selected appropriately depending on the purpose. Examples of other components include colorants such as dyes, pigments, and carbon black; silicone oils; surfactants; antioxidants; antimony oxides such as antimony trioxide, antimony tetraoxide, and antimony pentoxide; and conventionally known flame retardants such as brominated epoxy resins. One of these components can be used alone. Alternatively, two or more components can be used in combination.

[0050] The contents of other components are not limited to a specific content as long as the effects of this embodiment are not impaired, and the contents can be selected appropriately depending on the purpose.

[0051] -Physical properties of liquid sealant- <Gel time> Gel time is an index of how easily the liquid sealant hardens. A shorter gel time means that the liquid sealant cures quickly. A longer gel time means that the liquid sealant cures slowly. The gel time of the liquid sealant according to this embodiment at 120°C is 100 to 620 seconds, and preferably 100 to 390 seconds. By keeping the gel time within this range, molding defects can be suppressed while maintaining curability.

[0052] The gel time can be measured by the following method: A sample for evaluation (0.3 mL±0.1 mL) is poured onto a stainless steel plate heated to 120° C. Immediately after pouring, the sample for evaluation is stirred eccentrically on two axes (rotation speed: 120 rpm, revolution speed: 50 rpm) using an automatic curing time measuring device (trade name "Madoka", manufactured by Cyber ​​Corporation), and the time until gelation (torque judgment value: 20%) is measured as the gel time.

[0053] <Viscosity> The viscosity of the liquid sealant at 120°C (hot viscosity) is preferably 0.5 Pa·s to 40.0 Pa·s. If the viscosity is less than 0.5 Pa·s (low viscosity), the LCM may flow out of the mold during compression molding. If the viscosity is more than 40.0 Pa·s (high viscosity), some areas may not be filled with the sealant when the liquid sealant is injected. Note that the viscosity at 120°C is the viscosity when the liquid sealant is cured.

[0054] -Method for producing liquid sealant- The method for producing the liquid sealant is not limited to a specific method. An appropriate method can be selected depending on the purpose. An example of the production method is mixing and stirring the above components.

[0055] When the epoxy resin is solid, it is preferable to mix the epoxy resin which has been liquefied or fluidized by heating or the like.

[0056] Alternatively, the components can be mixed simultaneously. Alternatively, some of the components can be mixed first, and then the remaining components can be mixed. If it is difficult to uniformly disperse the filler in the epoxy resin, the epoxy resin and the filler can be mixed first, and then the remaining components can be mixed.

[0057] The device used for mixing and stirring is not limited to a specific device. An appropriate mixing and stirring device can be selected depending on the purpose. An example of a mixing and stirring device is a roll mill.

[0058] (Electronic Component) The electronic component according to this embodiment includes a support and a cured product of the liquid sealant described above. An example of the electronic component is an electronic component including a "semiconductor element and a support" sealed with the liquid sealant according to this embodiment.

[0059] <Support> The support used in this embodiment is not limited to a specific support as long as it can fix a semiconductor element. A support can be appropriately selected depending on the purpose. An example of the support is a substrate.

[0060] <<Substrate>> The substrate used in this embodiment is not limited to a specific substrate. A substrate can be selected appropriately depending on the purpose. Examples of substrates include lead frames, pre-wired tape carriers, wiring boards, glass, and silicon wafers. The size, shape, and material of the substrate used are not limited to specific standards as long as the substrate can be used as a normal substrate. The size, shape, and material of the substrate can be selected appropriately depending on the purpose.

[0061] <Semiconductor element> The semiconductor element is not limited to a specific element. A semiconductor element can be selected appropriately depending on the purpose. Examples of semiconductor elements include active elements such as semiconductor chips, transistors, diodes, and thyristors; and passive elements such as capacitors, resistors, resistor arrays, coils, and switches. The size, shape, and material of the semiconductor element are not limited to a specific standard as long as the semiconductor element is used as a normal semiconductor element. The size, shape, and material of the semiconductor element can be selected appropriately depending on the purpose.

[0062] The cured liquid sealant is provided between the support and the semiconductor element. The thickness of the cured liquid sealant is not limited to a specific thickness. The thickness can be selected appropriately depending on the purpose. For example, the cured product has a thickness of 10 μm or more and 800 μm or less. The shape of the liquid sealant is not limited to a specific shape. The shape of the liquid sealant can be selected appropriately depending on the purpose.

[0063] (Method for Manufacturing Electronic Component) The method for manufacturing an electronic component according to this embodiment includes filling with a liquid sealant and curing the liquid sealant. The manufacturing method may further include other operations as necessary.

[0064] <Filling with liquid sealant> The gap between the support and the semiconductor element disposed on the support is filled with a liquid sealant. The method for filling the liquid sealant is not limited to a specific method. An appropriate filling method can be selected depending on the purpose. Examples of methods for filling the liquid sealant include a dispensing method, a casting method, and a printing method. The amount of liquid sealant used is not limited to a specific amount. An appropriate filling amount can be selected depending on the purpose. For example, the filling amount can be selected so that the thickness of the cured product is 10 μm or more and 800 μm or less.

[0065] <Curing of Liquid Sealant> The liquid sealant filling the space between the support and the semiconductor element is cured. The method for curing the liquid sealant is not limited to a specific method. An appropriate curing method can be selected depending on the purpose. An example of a curing method is a method in which the support, the liquid sealant, and the semiconductor element are compressed under reduced pressure (compression molding).

[0066] <Other Operations> The above-mentioned other operations are not limited to specific operations. Other operations can be selected as appropriate depending on the purpose. For example, a semiconductor element may be disposed on a support.

[0067] (Semiconductor Device) The semiconductor device (semiconductor package) according to this embodiment includes the electronic component according to this embodiment. Furthermore, the semiconductor device may include other members as needed. The other members are not limited to specific members. Other members can be selected as appropriate depending on the purpose. [Example]

[0068] (Examples 1 to 18, Comparative Examples 1 to 7) Liquid sealants were prepared according to the formulations shown in Tables 1 to 5. The measured epoxy resin, curing agent, filler, and curing catalyst were premixed by manual stirring. In this way, a mixture was obtained. The mixture was then dispersed in a 4-inch ceramic triple roll mill (manufactured by Inoue Seisakusho Co., Ltd.) to form a paste. In this way, the liquid sealants were prepared. Note that the numerical values ​​in the tables represent parts by mass unless otherwise specified.

[0069]

[0070]

[0071]

[0072]

[0073]

[0074] The epoxy resins used in the examples and comparative examples are as follows: Aminophenol type epoxy resin (jER630, epoxy equivalent: 98 g / eq, manufactured by Mitsubishi Chemical Corporation) Aliphatic epoxy resin 1 (Epogose PT (general grade), epoxy equivalent: 435 g / eq, number average molecular weight: 700-800, manufactured by Yokkaichi Synthetic Co., Ltd.) Aliphatic epoxy resin 2 (SR-8EGS, epoxy equivalent: 262 / eq, number average molecular weight: 510-550, manufactured by Sakamoto Pharmaceutical Industry Co., Ltd.) Aliphatic epoxy resin 3 (PG-207GS, epoxy equivalent: 300 to 330 g / eq, number average molecular weight: 600 to 660, manufactured by Nippon Steel Chemical & Material Co., Ltd.) Naphthalene-type epoxy resin (HP4032D, epoxy equivalent: 140 g / eq, manufactured by DIC Corporation) Bisphenol A-type epoxy resin (RE410S, epoxy equivalent: 180 g / eq, manufactured by Nippon Kayaku Co., Ltd.)

[0075] The curing agents used in the examples and comparative examples are as follows: Phenol-based curing agent (MEH-8005, hydroxyl equivalent: 139 to 143 g / eq, manufactured by Meiwa Kasei Co., Ltd.) Alicyclic acid anhydride-based curing agent (HN-5500, manufactured by Showa Denko Materials Co., Ltd.)

[0076] The curing catalysts used in the examples and comparative examples are as follows: 2MZA (2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, manufactured by Shikoku Chemical Industry Co., Ltd.) 2E4MZ (2-phenyl-4-methylimidazole, manufactured by Shikoku Chemical Industry Co., Ltd.) 2P4MHZ (2-phenyl-4-methyl-5-hydroxymethylimidazole, manufactured by Shikoku Chemical Industry Co., Ltd.)

[0077] The fillers used in the examples and comparative examples are as follows: Silica nanofiller (YA050C, volume average particle size: 50 nm, manufactured by Admatechs Co., Ltd.) Silica filler 1 (SE1050-SMO, surface treated with 3-methacryloxypropyltrimethoxysilane, volume average particle size: 0.3 μm, manufactured by Admatechs Co., Ltd.) Silica filler 2 (MLV2114, volume average particle size: 20 μm, manufactured by Tatsumori Co., Ltd.) Alumina filler (alumina filler treated with N-phenyl-3-aminopropyltrimethoxysilane, volume average particle size: 1.0 μm)

[0078] The viscosity, gel time, and viscosity increase ratio of the obtained liquid sealant were measured. Furthermore, the moldability, stability, and flowability of the liquid sealant were evaluated. Tables 1 to 5 show the measurement and evaluation results.

[0079] <Viscosity> Using a viscometer (MARSIII, manufactured by HAAKE), the viscosity of an evaluation sample (0.3 mL ± 0.1 mL) placed on a plate heated to 120°C was measured under the conditions of a measurement frequency of 10 Hz, a strain of 0.5, a gap of 0.5 mm, and a measurement frequency of 1 second. The hot viscosity value 40 seconds after the start of measurement was obtained as the measured value.

[0080] <Gel Time> Using an automatic curing time measuring device (trade name "Madoka", manufactured by Cyber ​​Corporation), an evaluation sample (0.3 mL±0.1 mL) was placed on a stainless steel plate heated to 120° C. and stirred eccentrically on two axes (rotation speed: 120 rpm, revolution speed: 50 rpm) immediately after placement. The time from immediately after placement until gelation (torque judgment value was set to 20%) was measured as the gel time.

[0081] <Thickening ratio> Using an HB type viscometer (manufactured by Brookfield), the viscosity of the sample immediately after preparation was measured as the initial viscosity at 25°C and 20 rpm. Using the same method, the viscosity 24 hours after preparation was measured as the 24-hour viscosity. The viscosity increase ratio was calculated by dividing the 24-hour viscosity by the initial viscosity.

[0082] <Stability> The stability was evaluated based on the viscosity increase ratio measured as described above, according to the following evaluation criteria. When the gel time was short and the viscosity increase ratio was high, unfilled areas were sometimes generated when the liquid sealant was compression molded. -Evaluation criteria- A: Viscosity increase ratio is 1.9 times or less B: Viscosity increase ratio is more than 1.9 times

[0083] <Moldability (Moldability)> The obtained liquid sealant was placed on a silicon wafer having a diameter of 300 mm and a thickness of 775 μm. Next, using a molding device (WCM-300, manufactured by Apic Yamada Co., Ltd.), a molded product having a diameter of 292 mm and a thickness of 500 μm was obtained under the temperature rising condition of 120°C / 600 seconds. The time until the liquid sealant cured was measured. From the measured time, moldability was evaluated based on the following evaluation criteria. -Evaluation criteria- A: Less than 400 seconds B: 400 seconds or more and 620 seconds or less C: More than 620 seconds

[0084] <Fluidity> A 12-inch silicon wafer was prepared by half-dicing to a width of 25 μm and a depth of 300 μm. The prepared liquid sealant was applied onto this wafer. Next, the liquid sealant was hardened by compression molding using a molding device (WCM-300, manufactured by Apic Yamada Co., Ltd.). Cross-sections were observed using a scanning electron microscope to determine whether the obtained hardened product had completely filled the half-diced area of ​​25 μm in width and 300 μm in depth. From the obtained observation results, the fluidity was evaluated based on the following evaluation criteria. -Evaluation criteria- A: No unevenness of the filler, completely filled B: Unevenness of the filler, or not completely filled

[0085] As shown in Tables 1 to 5, the gel times of the liquid sealants in the Examples were all in the range of 100 to 620 seconds. The evaluation results for the stability, moldability, and fluidity of these liquid sealants were all good. On the other hand, the stability of Comparative Examples 2, 4, and 6, which had gel times of less than 100 seconds, was rated "B." Furthermore, the moldability of Comparative Examples 1, 3, 5, and 7, which had gel times of more than 620 seconds, was rated "C." Furthermore, of these Comparative Examples, the fluidity of Comparative Example 7 was rated "B." These findings demonstrate that by adjusting the gel time to the range of 100 to 620 seconds, a liquid sealant can be obtained that has good curability and can suppress molding defects.

[0086] The present embodiment and examples have been described. These described embodiments and examples are merely examples. It is not intended that these examples limit the scope of the present embodiment. The described embodiments can be implemented in various other forms. Various omissions, substitutions, and modifications are possible in the above-described embodiments without departing from the spirit of the present embodiment. The above-described embodiments and their modifications are included within the technical scope of the present embodiment. Similarly, the subject matter of the invention described in the claims and the scope of equivalents thereof also include these embodiments and their modifications.

Claims

1. Contains an epoxy resin, a hardener, a curing catalyst, and a filler, having a gel time of 100 seconds to 620 seconds at 120°C; Liquid sealant.

2. At 120°C, it has a viscosity of 0.5 Pa·s to 40.0 Pa·s. The liquid sealant according to claim 1 .

3. The epoxy resin contains an aliphatic epoxy resin and an aromatic epoxy resin. The liquid sealant according to claim 1 or 2.

4. The aliphatic epoxy resin has a molecular structure represented by the following general formula (1) and has a number average molecular weight of 200 to 2,000: The liquid sealant according to claim 3. 【Chemistry 1】 In the general formula (1), n ​​is a natural number from 1 to 15.

5. The curing agent contains a phenol. The liquid sealant according to claim 1 or 2.

6. The content of the curing agent is 1.0% by mass to 20.0% by mass with respect to the remaining components excluding the filler from the liquid sealing agent. The liquid sealant according to claim 1 or 2.

7. The filler has a volume average particle size of 0.05 μm to 10 μm. The liquid sealant according to claim 1 or 2.

8. The curing catalyst is a heterocyclic compound containing a nitrogen atom. The liquid sealant according to claim 1 or 2.

9. The content of the curing catalyst is 1.0% by mass to 12.0% by mass relative to the epoxy resin. The liquid sealant according to claim 1 or 2.

10. A support, a cured product of the liquid sealant according to claim 1 or 2, Including electronic components.

11. filling a gap between a support and a semiconductor element disposed on the support with the liquid sealant according to claim 1 or 2; and curing the liquid sealant. A method for manufacturing electronic components.

12. The electronic component according to claim 10, Semiconductor device.

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