JP7576545B2 - Sealing resin sheet - Google Patents

Description

The present invention relates to an encapsulating resin sheet, more specifically, to an encapsulating resin sheet for encapsulating elements.

Conventionally, it has been known to use a sealing sheet containing a thermosetting resin to seal an element connected to a terminal of a substrate by pressing, and then to thermally cure the thermosetting resin to form a hardened body from the sealing sheet (see, for example, Patent Document 1 below).

Patent document 1 discloses an example in which the amount of hardened material penetrating between the chip and the substrate from the side edge of the chip is 27 μm.

JP 2016-162909 A

However, when sealing multiple elements of different sizes and designs, or multiple elements connected to terminals of different sizes and designs, the fluidity of the thermosetting resin may differ due to the differences mentioned above, and it may not be possible to seal all of the multiple elements uniformly.

On the other hand, it is necessary to ensure excellent sealing of the element. In other words, it is necessary to ensure excellent sealing by covering the peripheral side surface of the element while reliably sealing the peripheral edges in the gaps of different thicknesses.

The present invention provides a sealing resin sheet that has excellent sealing properties for elements of different sizes and designs while reducing the amount of hardened material that penetrates into two gaps of different thicknesses.

The present invention (1) is an encapsulating resin sheet for encapsulating an element, which contains a thermosetting resin, a layered silicate compound, and a thermoplastic resin, and includes an encapsulating resin sheet in which the ratio (A/α) of the mass A of the layered silicate compound to the mass α of the thermoplastic resin is 0.3 or more and 2.0 or less.

The present invention (2) includes a sealing resin sheet described in (1) in which the content ratio B of the layered silicate compound is 3 mass% or more and 7 mass% or less.

The present invention (3) includes a sealing resin sheet described in (1) or (2), in which the thermoplastic resin has a glass transition temperature Tg of -30°C or higher and -10°C or lower.

The present invention (4) includes a sealing resin sheet described in any one of (1) to (3), in which the layered silicate compound has a surface modified with an organic component.

The present invention (5) includes a sealing resin sheet described in any one of (1) to (4), in which the thermoplastic resin contains a carboxyl group.

The sealing resin sheet of the present invention contains a thermosetting resin, a layered silicate compound, and a thermoplastic resin, and the ratio of the mass of the layered silicate compound to the mass of the thermoplastic resin is 0.3 or more. Therefore, when this sealing resin sheet is placed on multiple elements of different sizes and designs, and multiple elements connected to terminals of different sizes and designs, and heated to form a hardened body, the amount of the hardened body that enters the gaps between them can be controlled to uniformly seal the multiple elements.

In addition, the ratio of the mass of the layered silicate compound to the mass of the thermoplastic resin is 2.0 or less. This ensures that the peripheral side surface of the element is covered reliably, and the peripheral edges of gaps with different thicknesses are reliably sealed, providing excellent sealing properties for the element.

1A to 1D are cross-sectional views showing the process of manufacturing an electronic element package by encapsulating a plurality of electronic elements using one embodiment of the encapsulating resin sheet of the present invention, in which FIG. 1A shows the process of preparing an encapsulating resin sheet, FIG. 1B shows the process of preparing electronic elements, FIG. 1C shows the process of pressing the encapsulating resin sheet to form an encapsulated body, and FIG. 1D shows the process of heating the encapsulated body to form a hardened body. 2A and 2B show a device mounting board including the electronic device shown in FIG. 1B, where FIG. 2A is a plan view and FIG. 2B is a cross-sectional view taken along line XX in FIG. 2A. 3A to 3D are cross-sectional views of processes for manufacturing an electronic element package by encapsulating a plurality of electronic elements using an encapsulating multilayer resin sheet including the encapsulating resin sheet shown in FIG. 1A and a second encapsulating resin sheet, in which FIG. 3A illustrates a process for preparing the encapsulating multilayer resin sheet, FIG. 3B illustrates a process for preparing electronic elements, FIG. 3C illustrates a process for pressing the encapsulating multilayer resin sheet to form an encapsulated body, and FIG. 3D illustrates a process for heating the encapsulated body to form a hardened body.

One embodiment of the sealing resin sheet of the present invention is described below.

The sealing resin sheet is a resin sheet for sealing elements and has an approximately plate shape (film shape) extending in a planar direction perpendicular to the thickness direction.

The material of the sealing resin sheet contains a thermosetting resin, a layered silicate compound, and a thermoplastic resin. In other words, this material is a silicate-resin composition containing a thermosetting resin, a layered silicate compound, and a thermoplastic resin.

Examples of thermosetting resins include epoxy resins, silicone resins, urethane resins, polyimide resins, urea resins, melamine resins, unsaturated polyester resins, etc. These can be used alone or in combination of two or more.

As the thermosetting resin, an epoxy resin is preferably used. The epoxy resin is prepared as an epoxy resin composition containing a base resin, a curing agent, and a curing accelerator.

Examples of the base agent include bifunctional epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, modified bisphenol A type epoxy resin, modified bisphenol F type epoxy resin, and biphenyl type epoxy resin, and multifunctional epoxy resins having three or more functional groups such as phenol novolac type epoxy resin, cresol novolac type epoxy resin, trishydroxyphenylmethane type epoxy resin, tetraphenylolethane type epoxy resin, and dicyclopentadiene type epoxy resin. These base agents can be used alone or in combination of two or more types. As the base agent, preferably, bifunctional epoxy resins are used, and more preferably, bisphenol F type epoxy resins are used.

The lower limit of the epoxy equivalent of the base agent is, for example, 10 g/eq., preferably 100 g/eq. The upper limit of the epoxy equivalent of the base agent is, for example, 300 g/eq., preferably 250 g/eq.

The lower limit of the softening point of the base agent is, for example, 50°C, preferably 70°C, more preferably 72°C, and even more preferably 75°C. The upper limit of the softening point of the base agent is, for example, 130°C, preferably 110°C, and more preferably 90°C.

If the softening point of the base resin is equal to or higher than the lower limit, the encapsulating resin sheet 1 can flow in the process shown in Fig. 1C. This allows the time required for the process shown in Fig. 1C to be shortened, and one side of the encapsulating resin sheet 1 in the thickness direction to be flattened in the process shown in Fig. 1wC.

The lower limit of the proportion of the main agent in the material is, for example, 1 mass%, preferably 2 mass%. The upper limit of the proportion of the main agent in the material is, for example, 30 mass%, preferably 15 mass%. The lower limit of the proportion of the main agent in the epoxy resin composition is, for example, 30 mass%, preferably 50 mass%. The upper limit of the proportion of the main agent in the epoxy resin composition is, for example, 80 mass%, preferably 70 mass%.

The curing agent is a latent curing agent that cures the base agent by heating. Examples of the curing agent include phenolic resins such as phenol novolac resin. If the curing agent is a phenolic resin, the phenolic resin and the base agent together form a cured product that has high heat resistance and high chemical resistance. Therefore, the cured product has excellent sealing reliability.

The ratio of the curing agent is set to the following equivalent ratio. Specifically, the lower limit of the total of hydroxyl groups in the phenolic resin relative to 1 equivalent of epoxy groups in the base agent is, for example, 0.7 equivalents, preferably 0.9 equivalents. The upper limit of the total of hydroxyl groups in the phenolic resin relative to 1 equivalent of epoxy groups in the base agent is, for example, 1.5 equivalents, preferably 1.2 equivalents. Specifically, the lower limit of the number of parts of the curing agent contained per 100 parts by mass of the base agent is, for example, 20 parts by mass, preferably 40 parts by mass. The upper limit of the number of parts of the curing agent contained per 100 parts by mass of the base agent is, for example, 80 parts by mass, preferably 60 parts by mass.

The curing accelerator is a catalyst (thermal curing catalyst) that accelerates the curing of the base agent by heating. Examples of the curing accelerator include organic phosphorus compounds, such as imidazole compounds such as 2-phenyl-4,5-dihydroxymethylimidazole (2PHZ-PW). Preferably, an imidazole compound is used. The lower limit of the number of parts of the curing accelerator per 100 parts by mass of the base agent is, for example, 0.05 parts by mass. The upper limit of the number of parts of the curing accelerator per 100 parts by mass of the base agent is, for example, 5 parts by mass.

The content ratio of thermosetting resin in the material will be described later.

The layered silicate compound is dispersed in the thermosetting resin and thermoplastic resin (resin matrix) in the material (sealing resin sheet). The layered silicate compound is also a flow regulator when forming an encapsulant and a cured body (described below) from the sealing resin sheet. Specifically, it is a curing flow reducer that reduces the fluidity of the cured body when the sealing resin sheet is heated to form the cured body.

A layered silicate compound is, for example, a silicate having a structure (three-dimensional structure) in which layers extending two-dimensionally (in the plane direction) are stacked in the thickness direction, and is called a phyllosilicate.

Specific examples of layered silicate compounds include smectites such as montmorillonite, beidellite, nontronite, saponite, hectorite, sauconite, and stevensite, kaolinite, halloysite, talc, and mica. As layered silicate compounds, smectite is preferred from the viewpoint of improving mixability with thermosetting resins, and montmorillonite is more preferred.

The layered silicate compound may be an unmodified compound whose surface is not modified, or may be a modified compound whose surface is modified with an organic component. Preferably, the layered silicate compound is surface-modified with an organic component from the viewpoint of obtaining excellent affinity with thermosetting resins and thermoplastic resins. Specifically, examples of the layered silicate compound include organo-modified smectite whose surface is modified with an organic component, and more preferably, organo-modified bentonite whose surface is modified with an organic component.

Organic components include organic cations (onium ions) such as ammonium, imidazolium, pyridinium, and phosphonium.

Examples of ammonium include dimethyl distearyl ammonium, distearyl ammonium, octadecyl ammonium, hexyl ammonium, octyl ammonium, 2-hexyl ammonium, dodecyl ammonium, trioctyl ammonium, etc. Examples of imidazolium include methyl stearyl imidazolium, distearyl imidazolium, methyl hexyl imidazolium, dihexyl imidazolium, methyl octylimidazolium, dioctylimidazolium, methyl dodecyl imidazolium, didodecyl imidazolium, etc. Examples of pyridinium include stearyl pyridinium, hexyl pyridinium, octyl pyridinium, dodecyl pyridinium, etc. Examples of the phosphonium include dimethyl distearyl phosphonium, distearyl phosphonium, octadecyl phosphonium, hexyl phosphonium, octyl phosphonium, 2-hexyl phosphonium, dodecyl phosphonium, and trioctyl phosphonium. The organic cations can be used alone or in combination of two or more. Preferred is ammonium, and more preferred is dimethyl distearyl ammonium.

As the organically modified layered silicate compound, preferably, an organically modified smectite whose surface is modified with ammonium, and more preferably, an organically modified bentonite whose surface is modified with dimethyl distearyl ammonium, is used.

The lower limit of the average particle diameter of the layered silicate compound is, for example, 1 nm, preferably 5 nm, more preferably 10 nm. The upper limit of the average particle diameter of the layered silicate compound is, for example, 100 μm, preferably 50 μm, more preferably 10 μm. The average particle diameter of the layered silicate compound is determined as the D50 value (cumulative 50% median diameter) based on the particle size distribution determined by, for example, a particle size distribution measurement method in a laser scattering method.

As the layered silicate compound, commercially available products can be used. For example, the Esben series (manufactured by Hojun Co., Ltd.) is a commercially available organic bentonite product.

The content ratio of layered silicate compound will be described later.

The thermoplastic resin, together with the layered silicate compound, is a second curing flow reducer that reduces the fluidity of the cured body. The thermoplastic resin also serves as a second sealing flow improver and curing flow reducer.

Examples of thermoplastic resins include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, polybutadiene resin, polycarbonate resin, thermoplastic polyimide resin, polyamide resin (such as 6-nylon and 6,6-nylon), phenoxy resin, acrylic resin, saturated polyester resin (such as PET), polyamideimide resin, fluororesin, styrene-isobutylene-styrene block copolymer, etc. These thermoplastic resins can be used alone or in combination of two or more types.

As a thermoplastic resin, preferably, an acrylic resin is used from the viewpoint of improving dispersibility with the thermosetting resin.

Examples of acrylic resins include (meth)acrylic acid ester copolymers (preferably carboxyl group-containing acrylic acid ester copolymers) obtained by polymerizing monomer components including (meth)acrylic acid alkyl esters having linear or branched alkyl groups and other monomers (copolymerizable monomers).

Examples of alkyl groups include alkyl groups having 1 to 6 carbon atoms, such as methyl, ethyl, propyl, isopropyl, n-butyl, t-butyl, isobutyl, pentyl, and hexyl.

Examples of other monomers include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid; glycidyl group-containing monomers such as glycidyl acrylate and glycidyl methacrylate; acid anhydride monomers such as maleic anhydride and itaconic anhydride; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, and the like. ) 10-hydroxydecyl acrylate, 12-hydroxylauryl (meth)acrylate, or (4-hydroxymethylcyclohexyl)-methyl acrylate or other hydroxyl group-containing monomers, for example, styrene sulfonic acid, allyl sulfonic acid, 2-(meth)acrylamido-2-methylpropanesulfonic acid, (meth)acrylamidopropanesulfonic acid, sulfopropyl (meth)acrylate, (meth)acryloyloxynaphthalenesulfonic acid or other sulfonic acid group-containing monomers, 2-hydroxyethylacryloylphosphate or other phosphoric acid group-containing monomers, for example, styrene monomers, and for example, acrylonitrile. These may be used alone or in combination of two or more.
Preferably, a carboxyl group-containing monomer or a hydroxyl group-containing monomer is used, and more preferably, a carboxyl group-containing monomer is used.

Preferred examples of thermoplastic resins include thermoplastic resins containing carboxyl groups and thermoplastic resins containing carboxyl groups and hydroxyl groups.

The lower limit of the glass transition temperature Tg of the thermoplastic resin is -70°C, preferably -50°C, and more preferably -30°C. The upper limit of the glass transition temperature Tg of the thermoplastic resin is, for example, 0°C, preferably -5°C, and more preferably -10°C. The glass transition temperature Tg is a theoretical value calculated, for example, by the Fox formula, and a specific calculation method thereof is described, for example, in JP 2016-175976 A.

If the glass transition temperature Tg of the thermoplastic resin is equal to or higher than the lower limit described above, the amount of the hardened body penetrating into both gaps of different thicknesses can be reliably reduced. If the glass transition temperature Tg of the thermoplastic resin is equal to or lower than the upper limit described above, the formation of unfilled portions outside the gaps can be suppressed.

The lower limit of the weight average molecular weight of the thermoplastic resin is, for example, 100,000, preferably 300,000. The upper limit of the weight average molecular weight of the thermoplastic resin is, for example, 1.2 million, preferably 1 million. The weight average molecular weight is measured by gel permeation chromatography (GPC) based on a standard polystyrene equivalent value.

The content ratio of thermoplastic resin is adjusted to the extent that a hardened body can be produced from the sealing resin sheet, as described below.

<Contents of thermosetting resin, layered silicate compound, and thermoplastic resin>
The lower limit of the ratio (A/α) of the mass A of the layered silicate compound to the mass α of the thermoplastic resin is 0.3, preferably 0.5, more preferably 0.6, even more preferably 0.7, and particularly preferably 0.9.

In addition, the upper limit of the ratio (A/α) of the mass A of the layered silicate compound to the mass α of the thermoplastic resin is 2.0, preferably 1.4, more preferably 1.2, even more preferably 1.1, and particularly preferably 1.0.

If the ratio (A/α) of the mass A of the layered silicate compound to the mass α of the thermoplastic resin falls below the lower limit mentioned above, unfilled areas where no hardened body is present (no hardened body is formed) will be formed outside the gap between the element and the substrate, resulting in reduced reliability.

On the other hand, if the ratio (A/α) of the mass A of the layered silicate compound to the mass α of the thermoplastic resin exceeds the upper limit mentioned above, the amount of the hardened body penetrating into the two gaps of different thicknesses (corresponding to the first gap 26 and the second gap 36 described below) cannot be reduced.

The lower limit of the content ratio B of the layered silicate compound in the material (sealing resin sheet) is, for example, 0.1 mass%, preferably 1 mass%, more preferably 2 mass%, even more preferably 3 mass%, and particularly preferably 4 mass%. The upper limit of the content ratio B of the layered silicate compound in the material (sealing resin sheet) is, for example, 25 mass%, preferably 15 mass%, more preferably 10 mass%, and even more preferably 8 mass%.

If the content ratio B of the layered silicate compound is equal to or greater than the lower limit described above, the fluidity of the sealing resin sheet can be reduced, and the amount of the hardened body penetrating into the gaps can be reduced. If the content ratio B of the layered silicate compound is equal to or less than the upper limit described above, the layered silicate compound can be sufficiently dispersed in the sealing resin sheet, and a sealing resin sheet with uniform fluidity can be produced.

The lower limit of the proportion of thermoplastic resin in the material (sealing resin sheet) is, for example, 1 mass%, preferably 2 mass%. The upper limit of the proportion of thermoplastic resin in the material is, for example, 10 mass%, preferably 5 mass%.

The lower limit of the proportion of the thermoplastic resin relative to the total amount of the thermoplastic resin and the thermosetting resin is, for example, 5% by mass, preferably 15% by mass. The upper limit of the proportion of the thermoplastic resin relative to the total amount of the thermoplastic resin and the thermosetting resin is, for example, 40% by mass, preferably 25% by mass.

The lower limit of the content of the thermosetting resin in the material (sealing resin sheet) is, for example, 5 mass%, preferably 15 mass%, more preferably 17 mass%, and even more preferably 18 mass%. The upper limit of the content of the thermosetting resin in the material (sealing resin sheet) is, for example, 30 mass%, preferably 25 mass%, and more preferably 20 mass%.

<Other ingredients>
The material may further contain inorganic fillers other than the layered silicate compound, pigments, silane coupling agents, and other additives.

Examples of inorganic fillers include silicate compounds other than layered silicate compounds such as orthosilicates, sorosilicates, and inosilicates, and silicon compounds such as quartz (silicic acid), silica (anhydrous silicic acid), and silicon nitride (silicon compounds other than layered silicate compounds). Examples of inorganic fillers include alumina, aluminum nitride, and boron nitride. These can be used alone or in combination of two or more. Preferably, silicon compounds other than layered silicate compounds are used, and more preferably, silica.

The shape of the inorganic filler is not particularly limited, and examples thereof include an approximately spherical shape, an approximately plate shape, an approximately needle shape, and an irregular shape. An approximately spherical shape is preferable.

The upper limit of the average value of the maximum length of the inorganic filler (similar to the average particle diameter if the filler is approximately spherical) is, for example, 50 μm, preferably 20 μm, and more preferably 10 μm. The lower limit of the average value of the maximum length of the inorganic filler is, for example, 0.1 μm, and preferably 0.5 μm. The average particle diameter of the inorganic filler is determined as the D50 value (cumulative 50% median diameter) based on the particle size distribution determined, for example, by a particle size distribution measurement method in a laser scattering method.

The inorganic filler may also include a first filler and a second filler having an average maximum length that is smaller than the average maximum length of the first filler.

The lower limit of the average maximum length of the first filler is, for example, 1 μm, preferably 3 μm. The upper limit of the average maximum length of the first filler is, for example, 50 μm, preferably 30 μm.

The upper limit of the average value of the maximum length of the second filler is, for example, 0.9 μm, preferably 0.8 μm. The lower limit of the average value of the maximum length of the second filler is, for example, 0.01 μm, preferably 0.1 μm.

The lower limit of the ratio of the average maximum length of the first filler to the average maximum length of the second filler is, for example, 2, preferably 5. The upper limit of the ratio of the average maximum length of the first filler to the average maximum length of the second filler is, for example, 50, preferably 20.

The materials of the first filler and the second filler may be the same or different.

Furthermore, the surface of the inorganic filler may be partially or entirely treated with a silane coupling agent or the like.

The lower limit of the content of the inorganic filler in the material (sealing resin sheet) is, for example, 50% by mass, preferably 55% by mass, more preferably 60% by mass, and even more preferably 65% by mass. The upper limit of the content of the inorganic filler in the material (sealing resin sheet) is, for example, 90% by mass, preferably 85% by mass, more preferably 80% by mass, and even more preferably 75% by mass.

The lower limit of the number of parts of the layered silicate compound contained per 100 parts by mass of the inorganic filler is, for example, 1 part by mass, preferably 2 parts by mass, more preferably 3 parts by mass, and even more preferably 5 parts by mass. The upper limit of the number of parts of the layered silicate compound contained per 100 parts by mass of the inorganic filler is, for example, 25 parts by mass, preferably 20 parts by mass, more preferably 15 parts by mass, and even more preferably 10 parts by mass.

If the content ratio and/or number of parts of inorganic filler is equal to or greater than the lower limit described above, the sealing resin sheet 1 can flow in the process shown in Figure 1C.

When the inorganic filler includes a first filler and a second filler, the lower limit of the content ratio of the first filler in the material (sealing resin sheet) is, for example, 30 mass%, preferably 40 mass%, in the material. The upper limit of the content ratio of the first filler in the material (sealing resin sheet) is, for example, 60 mass%, preferably 50 mass%, in the material. The lower limit of the number of parts of the second filler contained relative to 100 parts by mass of the first filler is, for example, 30 parts by mass, preferably 40 parts by mass, more preferably 50 parts by mass. The upper limit of the number of parts of the second filler contained relative to 100 parts by mass of the first filler is, for example, 70 parts by mass, preferably 60 parts by mass, more preferably 55 parts by mass.

Examples of pigments include black pigments such as carbon black. The lower limit of the pigment particle size is, for example, 0.001 μm. The upper limit of the pigment particle size is, for example, 1 μm. The lower limit of the pigment ratio to the material is, for example, 0.1 mass%. The pigment particle size is the arithmetic mean diameter obtained by observing the pigment with an electron microscope. The upper limit of the pigment ratio to the material is, for example, 2 mass%.

Examples of the silane coupling agent include silane coupling agents containing an epoxy group. Examples of the silane coupling agent containing an epoxy group include 3-glycidoxydialkyldialkoxysilanes such as 3-glycidoxypropylmethyldimethoxysilane and 3-glycidoxypropylmethyldiethoxysilane, and 3-glycidoxyalkyltrialkoxysilanes such as 3-glycidoxypropyltrimethoxysilane and 3-glycidoxypropyltriethoxysilane. Preferably, 3-glycidoxyalkyltrialkoxysilane is used. The lower limit of the content of the silane coupling agent in the material is, for example, 0.1% by mass, preferably 1% by mass. The upper limit of the content of the silane coupling agent in the material is, for example, 10% by mass, preferably 5% by mass.

To obtain this sealing resin sheet, the above-mentioned components are mixed in the above-mentioned ratios to prepare a material. Preferably, the above-mentioned components are thoroughly stirred to uniformly disperse the layered silicate compound in the thermosetting resin and the thermoplastic resin.

If necessary, a solvent (such as a ketone such as methyl ethyl ketone) is further added to prepare a varnish. The varnish is then applied to a release sheet (not shown) and then dried by heating to produce a sealing resin sheet having a sheet shape. On the other hand, it is also possible to form a sealing resin sheet from the material by kneading extrusion without preparing a varnish.

The encapsulating resin sheet that is formed is in B stage (semi-cured state), specifically, a state before C stage. In other words, it is a state before complete curing. The encapsulating resin sheet is formed into a B stage sheet from A stage material by heating during the drying process described above and heating during extrusion kneading.

The lower limit of the thickness of the encapsulating resin sheet is, for example, 10 μm, preferably 25 μm, and more preferably 50 μm. The upper limit of the thickness of the encapsulating resin sheet is, for example, 3000 μm, preferably 1000 μm, more preferably 500 μm, and even more preferably 300 μm.

Next, a method of encapsulating an electronic element, as an example of an element, with an encapsulating resin sheet to manufacture an electronic element package 50 will be described with reference to Figures 1A to 2B.

In Figure 2B, the components visible on the A-A section line in Figure 2A are drawn using hatching, while the components not visible on the section line but visible away from the A-A section line are drawn without hatching.

In this method, as shown in Figure 1A, first, a sealing resin sheet 1 is prepared. The sealing resin sheet 1 has one side and another side in the thickness direction that face each other in the thickness direction.

Separately, an electronic element 21 is prepared as shown in Figures 1B and 2A to 2B.

As shown in Figures 2A and 2B, the electronic element 21 includes electronic components and has a generally flat plate shape (chip shape) extending in the planar direction. An electrode (not shown) is provided on the other surface 28 in the thickness direction of the electronic element 21. The electrodes (not shown) are arranged at intervals from each other on the peripheral edge of the electronic element 21. The electronic element 21 contains, for example, a known electronic material.

The electronic element 21 is mounted on the substrate 22 via bumps 23 so that two gaps (a first gap 26 and a second gap 36) of different thicknesses are formed. The electronic element 21 and the substrate 22 are provided on an element mounting substrate 24. The element mounting substrate 24 includes the first gap 26 and the second gap 36.

The substrate 22 has a generally flat plate shape extending in the planar direction. One thickness-wise surface 25 of the substrate 22 is, for example, parallel to the other thickness-wise surface 28 of the electronic element 21.

The length T2 between one thickness-wise surface 25 of the substrate 22 and the other thickness-wise surface 28 of the electronic element 21 corresponds to the thickness T2 of the second gap 36 between the substrate 22 and the electronic element 21. The lower limit of the thickness T2 of the second gap 36 is, for example, 10 μm, preferably 30 μm. The upper limit of the thickness T2 of the second gap 36 is, for example, 200 μm, preferably 100 μm.

A terminal 29 is provided on one thickness-wise surface 25 of the substrate 22, which is electrically connected to an electrode (not shown) of the electronic element 21.

The terminals 29 extend along the peripheral edge of the electronic element 21 in a plan view. The terminals 29 have a predetermined thickness T0. A plurality of the terminals 29 are arranged at intervals from each other in the planar direction. Each of the plurality of terminals 29 is provided corresponding to a respective one of the plurality of electrodes (not shown) of the electronic element 21.

The thickness T0 of the terminal 29 is the length between one thickness direction surface 25 of the substrate 22 and one thickness direction surface 30 of the terminal 29. The thickness T0 of the terminal 29 is thinner than the thickness T2 of the second gap 36. Specifically, the lower limit of the thickness T0 of the terminal 29 is, for example, 5 μm, or preferably 15 μm.
The upper limit of the thickness T0 of the terminal 29 is, for example, 100 μm, or preferably 50 μm.

The terminal 29 is electrically connected to an electrode (not shown) of the electronic element 21 via a bump 23.

A plurality of bumps 23 are provided corresponding to a plurality of terminals 29. Each of the plurality of bumps 23 is disposed between a corresponding electrode 29 of the electronic element 21 and a terminal (not shown) of the substrate 22. Examples of materials for the bumps 23 include solder and metals such as gold.
The thickness T1 of the bump 23 corresponds to the thickness T1 of the first gap 26 described below. When one thickness direction surface 25 of the substrate 22 and the other thickness direction surface 28 of the electronic element 21 are parallel to each other, the thickness T1 of the bump 23 corresponds to a value (T2-T0) obtained by subtracting the thickness T0 of the terminal 29 from the thickness T2 of the second gap 36. Specifically, the lower limit of the thickness T1 of the bump 23 is, for example, 5 μm, or preferably 15 μm. The upper limit of the thickness T1 of the bump 23 is, for example, 100 μm, or preferably 50 μm.

The first gap 26 is a gap (gap or cavity) formed by the bump 23 being interposed between the electronic element 21 and the terminal 29. Therefore, the thickness T1 of the first gap 26 is the same as the thickness T1 of the bump 23. The first gap 26 is also a space between the other thickness-wise surface 28 of the electronic element 21 and one thickness-wise surface 30 of the terminal 29. The first gap 26 partially overlaps with the side edge 75 of the electronic element 21 in a plan view. In more detail, the first gap 26 is the area where the electronic element 21 and the terminal 29 overlap when projected in the thickness direction, excluding the bump 23.

The second gap 36 has a thickness T2 that is thicker than the thickness T1 of the first gap 26. The second gap 36 is connected to the first gap 26. Specifically, the thickness T2 of the second gap 36 is the total thickness of the thickness T1 of the first gap 26 and the thickness T0 of the terminal 29. The second gap 36 is between the other thickness-wise surface 28 of the electronic element 21 and the one thickness-wise surface 25 of the substrate 22 (a gap or a cavity). The second gap 36 is the area where the electronic element 21 and the substrate 22 overlap when projected in the thickness direction, excluding the terminal 29. The second gap 36 also partially overlaps with the side edge 75 of the electronic element 21.

The lower limit of the ratio (T1/T2) of the thickness T1 of the first gap 26 to the thickness T2 of the second gap 36 is, for example, 0.1, preferably 0.2. The upper limit of the ratio (T1/T2) of the thickness T1 of the bump 23 to the thickness T2 of the gap between the substrate 22 and the electronic element 21 is, for example, 0.6, preferably 0.5.

The first gap 26 and the second gap 36 overlap the entire side edge 75 of the electronic element 21.

Next, as shown in FIG. 1B, the encapsulating resin sheet 1 is placed on the electronic element 21. Specifically, the other thickness-wise surface of the encapsulating resin sheet 1 is brought into contact with one thickness-wise surface of the electronic element 21.

Next, as shown in Fig. 1C, the sealing resin sheet 1 and the element mounting board 24 are pressed. Specifically, the sealing resin sheet 1 and the element mounting board 24 are heat-pressed.

For example, the sealing resin sheet 1 and the element mounting substrate 24 are sandwiched in the thickness direction and pressed by a press 27 having two flat plates. The flat plates of the press 27 are equipped with, for example, a heat source (not shown).

The pressing conditions (pressure, time, temperature, etc.) are not particularly limited, and conditions are selected such that the sealing resin sheet 1 can cover the peripheral side of the electronic element 21 while not damaging the element mounting substrate 24. More specifically, the pressing conditions are set such that the sealing resin sheet 1 flows outside the peripheral side of the electronic element 21 to cover the peripheral side of the electronic element 21 while contacting both one thickness direction surface 25 of the substrate 22 that does not overlap the electronic element 21 in a plan view and one thickness direction surface 30 of the terminal 29.

Specifically, the lower limit of the pressing pressure is, for example, 0.05 MPa, preferably 0.1 MPa. The upper limit of the pressing pressure is, for example, 10 MPa, preferably 5 MPa. The lower limit of the pressing time is, for example, 0.3 minutes, preferably 0.5 minutes. The upper limit of the pressing time is, for example, 10 minutes, preferably 5 minutes.

Specifically, the lower limit of the heating temperature is, for example, 40°C, preferably 60°C. The upper limit of the heating temperature is, for example, 100°C, preferably 95°C.

By pressing the sealing resin sheet 1, the sealing resin sheet 1 is plastically deformed to correspond to the external shape of the electronic element 21. The other thickness-wise surface of the sealing resin sheet 1 is deformed into a shape corresponding to one thickness-wise surface and peripheral side surface of the electronic element 21, one thickness-wise surface 25 of the substrate 22 that does not overlap the electronic element 21 in a plan view, and one thickness-wise surface 30 of the terminal 29.

As a result, the sealing resin sheet 1 closes the peripheral edges of the first gap 26 and the second gap 36. This allows the electronic element 21 to be sealed with excellent sealing properties.

The sealing resin sheet 1 undergoes plastic deformation while maintaining the B stage.

As a result, the sealing resin sheet 1 covers the peripheral side surfaces of each of the multiple electronic elements 21 while contacting one thickness-wise surface 25 of the substrate 22 that does not overlap with the electronic elements 21 in a planar view.

As a result, the sealing body 31 that seals the electronic element 21 is formed (produced) from the sealing resin sheet 1. One side in the thickness direction of the sealing body 31 becomes a flat surface.

At this time, the sealing body 31 is allowed to enter slightly into the first gap 26 and the second gap 36.

Then, as shown in FIG. 1D, the sealing body 31 is heated to form a hardened body 41 from the sealing body 31.

Specifically, the sealing body 31 and the element mounting board 24 are removed from the press 27, and then the sealing body 31 and the element mounting board 24 are heated in a dryer under atmospheric pressure.

The lower limit of the heating temperature (cure temperature) is, for example, 100°C, preferably 120°C. The upper limit of the heating temperature (cure temperature) is, for example, 200°C, preferably 180°C. The lower limit of the heating time is, for example, 10 minutes, preferably 30 minutes. The upper limit of the heating time is, for example, 180 minutes, preferably 120 minutes.

By heating the sealing body 31 as described above, a C-stage (fully cured) hardened body 41 is formed from the sealing body 31. One surface in the thickness direction of the hardened body 41 is an exposed surface.

Furthermore, the edge of the sealing body 31, which is allowed to slightly penetrate into the first gap 26 and the second gap 36, is allowed to penetrate further slightly into the inside of the first gap 26 and the second gap 36 and become the hardened body 41.

This sealing resin sheet 1 contains a layered silicate compound, a layered silicate compound, and a thermoplastic resin, and the ratio (A/α) of the mass A of the layered silicate compound to the mass α of the thermoplastic resin is 0.3 or more. Therefore, when this sealing resin sheet 1 is placed on multiple electronic elements 21 of different sizes and designs, and multiple electronic elements 21 connected to terminals 29 of different sizes and designs, and heated to form a hardened body 41, the amount of hardened body 41 entering these first gaps 26 and second gaps 36 can be controlled to uniformly seal the multiple electronic elements 21.

For example, when this sealing resin sheet 1 is placed on an electronic element 21 that forms different first and second gaps 26 and 36 with respect to a substrate 22 and a terminal 29, and the sealing resin sheet 1 (sealing body 31) is heated to form a hardened body 41 as shown in FIG. 1D, it is possible to reduce the amount of hardened body 41 penetrating into both the first and second gaps 26 and 36. Specifically, it is possible to reduce both the first hardened body penetration length Y1 and the second hardened body penetration length Y2 (see FIG. 1D and FIG. 3D) that are described in detail in the examples.

On the other hand, the ratio (A/α) of the mass A of the layered silicate compound to the mass α of the thermoplastic resin is 2.0 or less. Therefore, the peripheral side surface of the electronic element 21 is reliably covered, and the peripheral edges of the first gap 26 and the second gap 36 are reliably closed, that is, the formation of unfilled portions is suppressed, and excellent sealing properties for the electronic element 21 are achieved.

In addition, in this sealing resin sheet 1, if the lower limit of the content ratio B of the layered silicate compound is 3 mass% or more, both the first hardened body penetration length Y1 and the second hardened body penetration length Y2 can be reduced. If the lower limit of the content ratio B of the layered silicate compound is 7 mass% or less, the edges of the first gap 26 and the second gap 36 can be reliably blocked.

Furthermore, if the glass transition temperature Tg of the thermoplastic resin is -30°C or higher, the layered silicate compound can be sufficiently dispersed in the sealing resin sheet, and a sealing resin sheet with uniform fluidity can be produced. If the glass transition temperature Tg of the thermoplastic resin is -10°C or lower, the fluidity of the sealing resin sheet can be reduced, and the amount of the cured body penetrating into the first gap 26 and the second gap 36 can be reduced.

If the surface of the layered silicate compound is modified with an organic component, the layered silicate compound can have good affinity with the thermosetting resin and the thermoplastic resin, and therefore both the first hardened body penetration length Y1 and the second hardened body penetration length Y2 can be reliably reduced.

<Multi-layer resin sheet for sealing>
Also, as shown in Figures 3A to 3D, the electronic element 21 can be encapsulated by an encapsulating multilayer resin sheet 11 having an encapsulating resin sheet 1 and a second encapsulating resin sheet 12 in that order on one side in the thickness direction, and then a cured body 41 can be formed.

The encapsulating multilayer resin sheet 11 comprises an encapsulating resin sheet 1 and a second encapsulating resin sheet 12 arranged over the entire surface of one side in the thickness direction of the encapsulating resin sheet 1. Preferably, the encapsulating multilayer resin sheet 11 comprises only the encapsulating resin sheet 1 and the second encapsulating resin sheet 12.

The material of the second sealing resin sheet 12 is the same as the material of the sealing resin sheet 1, except that it does not contain a layered silicate compound. The lower limit of the ratio of the thickness of the second sealing resin sheet 12 to the thickness of the sealing resin sheet 1 is, for example, 0.5, preferably 1, and more preferably 2. The upper limit of the ratio of the thickness of the second sealing resin sheet 12 to the thickness of the sealing resin sheet 1 is, for example, 10, and preferably 5.

The lower limit of the thickness of the encapsulating multilayer resin sheet 11 is, for example, 50 μm, preferably 100 μm, and more preferably 150 μm. The upper limit of the thickness of the encapsulating multilayer resin sheet 11 is, for example, 3000 μm, preferably 1000 μm, more preferably 500 μm, and even more preferably 300 μm.

A method for encapsulating multiple electronic elements 21 with an encapsulating multilayer resin sheet 11 and then forming a cured body 41 to manufacture an electronic element cured body package 50 is described with reference to Figures 3A to 3D.

As shown in Figure 3A, a sealing multilayer resin sheet 11 is prepared. Specifically, the sealing resin sheet 1 and the second sealing resin sheet 12 are bonded together.

As shown in FIG. 3B, a number of electronic elements 21 are prepared to be mounted on a substrate 22.

Next, the encapsulating multilayer resin sheet 11 is placed on the electronic element 21 so that the other thickness-wise side of the encapsulating resin sheet 1 contacts one thickness-wise side of the electronic element 21.

As shown in Figure 3C, the sealing resin sheet 1 and the element mounting substrate 24 are then pressed.

When pressed, the sealing resin sheet 1 flows and penetrates between the adjacent electronic elements 21. On the other hand, since the second sealing resin sheet 12 does not contain a layered silicate compound, even when pressed, its fluidity does not improve and remains low, so that penetration between the adjacent electronic elements 21 is suppressed.

This results in the formation of an encapsulating body 341 from the encapsulating multilayer resin sheet 11, which encapsulates multiple electronic elements 21.

Then, as shown in FIG. 3D, the sealing body 31 is heated to form a hardened body 41 from the sealing body 31.

In addition, if the sealing resin sheet 1 contains an inorganic filler at a ratio equal to or greater than the above-mentioned lower limit, and the second sealing resin sheet 12 contains an inorganic filler at a ratio equal to or greater than the above-mentioned lower limit, the sealing resin sheet 1 and the second sealing resin sheet 12 can flow by pressing as shown in the following Figure 3C.

At this time, the sealing resin sheet 1 contacts the electronic element 21, while the second sealing resin sheet 12 is located on the opposite side of the electronic element 21 with respect to the sealing resin sheet 1. In other words, the edges of the sealing body 31 facing the first gap 26 and the second gap 36 are formed from the sealing resin sheet 1. On the other hand, one surface in the thickness direction of the sealing body 31 is formed from the second sealing resin sheet 12.

Furthermore, since the sealing multilayer resin sheet 11 has the above-mentioned sealing resin sheet 1, the amount of hardened body 41 penetrating into the first gap 26 and the second gap 36 can be reduced.

In particular, if the sealing resin sheet 1 and the second sealing resin sheet 12 contain a base resin of epoxy resin having a softening point of 50° C. or more and 130° C. or less, the sealing resin sheet 1 and the second sealing resin sheet 12 can flow in the process shown in Fig. 3C. This allows the time for the process shown in Fig. 3C to be shortened, and one surface in the thickness direction of the second sealing resin sheet 12 to be flattened in the process shown in Fig. 3C.

Furthermore, if the sealing resin sheet 1 and the second sealing resin sheet 12 contain a phenolic resin as a curing agent together with the epoxy resin as the main agent, the cured body 41 has high heat resistance and high chemical resistance. Therefore, the cured body 41 has excellent sealing reliability.

3C, the second sealing resin sheet 12 is fluidized by the pressing force, and one surface in the thickness direction becomes flat. Also, in the process shown in FIG. 3C, in the sealing multilayer resin sheet 11, as described above, the sealing resin sheet 1, together with the second sealing resin sheet 12, is softened and fluidized by the pressing force, and deforms to follow the external shape of the electronic element 21. In the process shown in FIG. 3C, the sealing resin sheet 1 is allowed to slightly enter the first gap 26 and the second gap 36.

3D , the flow of the encapsulating resin sheet 1 is suppressed based on the decrease in complex viscosity η ^* accompanying the rise in temperature, and excessive penetration into the first gap 26 and the second gap 36 is suppressed. That is, in the cured body 41 obtained by curing the encapsulating multilayer resin sheet 11 including the encapsulating resin sheet 1, the cured body penetration length Y can be reduced.

In the following modifications, the same reference numerals are used for the same components and steps as those in the above-described embodiment, and detailed descriptions thereof will be omitted. In addition, each modification can achieve the same effects as those in the embodiment, unless otherwise specified. Furthermore, the embodiment and its modifications can be appropriately combined.

Although the first gap 26 and the second gap 36 are mentioned as different gaps, there may be three or more types of gaps with different thicknesses.

In addition, the multiple gaps having different thicknesses are formed in one electronic element 21, but for example, each of the multiple gaps having different thicknesses may be formed in each of the multiple electronic elements 21. Specifically, the first gap 26 may be formed in one electronic element 21, and the second gap 36 may be formed in the other electronic element 21.

In one embodiment, the electronic element 21 is encapsulated with one layer of encapsulating resin sheet 1. However, although not shown, the electronic element 21 can also be encapsulated with multiple encapsulating resin sheets 1 (laminate sheets).

In addition, the second sealing resin sheet 12 in the sealing multilayer resin sheet 11 may be multilayered.

As an example of an element, there is given an electronic element 21 arranged across a gap 26 from one thickness-wise surface 25 of the substrate 22, which is sealed with the sealing resin sheet 1; however, for example, although not shown, there can also be given an electronic element 21 in contact with one thickness-wise surface 25 of the substrate 22, which can be sealed with the sealing resin sheet 1.

Although electronic element 21 has been given as an example of an element, a semiconductor element could also be mentioned.

The present invention will be described in more detail below with reference to Preparation Examples, Comparative Preparation Examples, Examples, and Comparative Examples. However, the present invention is not limited to these Preparation Examples, Comparative Preparation Examples, Examples, and Comparative Examples.
In addition, specific numerical values such as blending ratios (content ratios), physical property values, parameters, etc. used in the following description can be replaced with the upper limit (a numerical value defined as "not more than" or "less than") or lower limit (a numerical value defined as "not less than" or "exceeding") of the corresponding blending ratios (content ratios), physical property values, parameters, etc. described in the above "Form for implementing the invention."

The components used in the preparation examples and comparative preparation examples are shown below.

Layered silicate compound: Esben NX manufactured by Hojun Co., Ltd. (organic bentonite whose surface is modified with dimethyl distearyl ammonium)
Base resin: YSLV-80XY manufactured by Nippon Steel Chemical Co., Ltd. (bisphenol F type epoxy resin, high molecular weight epoxy resin, epoxy equivalent 200 g/eq., softening point 80° C.)
Hardener: LVR-8210DL manufactured by Gun-ei Chemical Industry Co., Ltd. (novolac type phenolic resin, latent hardener, hydroxyl equivalent: 104 g/eq., softening point: 60° C.)
Curing accelerator: 2PHZ-PW (2-phenyl-4,5-dihydroxymethylimidazole) manufactured by Shikoku Chemical Industry Co., Ltd.
Acrylic resin 1: HME-2006M manufactured by Negami Chemical Industries, a carboxyl group-containing acrylic acid ester copolymer (acrylic polymer), weight average molecular weight: 600,000, glass transition temperature (Tg): -30°C, methyl ethyl ketone solution with a solid content of 20% by mass. Acrylic resin 2: Teisan Resin SG-70L manufactured by Nagase ChemteX Corporation, a carboxyl group- and hydroxyl group-containing acrylic acid ester copolymer (acrylic polymer), weight average molecular weight 900,000, glass transition temperature (Tg): -10°C, methyl ethyl ketone solution with a solid content of 12.5% by mass. Silane coupling agent: KBM-403 (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd.
First filler: FB-8SM (spherical fused silica powder (inorganic filler), average particle size 7.0 μm)
Second filler: Inorganic filler obtained by surface-treating SC220G-SMJ (average particle size 0.5 μm) manufactured by Admatechs Co., Ltd. with 3-methacryloxypropyltrimethoxysilane (product name: KBM-503 manufactured by Shin-Etsu Chemical Co., Ltd.). Inorganic particles surface-treated with 1 part by mass of a silane coupling agent per 100 parts by mass of the inorganic filler.

Carbon black: Mitsubishi Chemical #20, particle size 50 nm

Preparation Examples 1 to 6 and Comparative Preparation Examples 1 to 4
Varnishes of the materials were prepared according to the formulations shown in Tables 1 to 3. The varnishes were applied to the surface of a release sheet and then dried at 120° C. for 2 minutes to produce a 65 μm-thick encapsulating resin sheet 1. The encapsulating resin sheet 1 was in the B-stage.

Preparation Example 7
A varnish of the material was prepared according to the formulation shown in Table 4. The varnish was applied to the surface of a release sheet and then dried at 120° C. for 2 minutes to prepare a second sealing resin sheet 12 having a thickness of 195 μm. The second sealing resin sheet 12 was in a B-stage.

Examples 1 to 6 and Comparative Examples 1 and 2
In the combination of preparation examples shown in Table 5, the encapsulating resin sheet and the second encapsulating resin sheet were laminated together to prepare an encapsulating multilayer resin sheet having a thickness of 260 μm.

Evaluation The following steps A to E were carried out to measure the first hardened body penetration length Y1 and the second highly hardened body penetration length Y2.

Step A: As shown in Figure 3A, a sample sheet 61 having a length of 10 mm, a width of 10 mm and a thickness of 260 μm is prepared from the sealing multilayer resin sheet 11 of each embodiment and each comparative example.

Step B: As shown in Figure 3B, prepare a dummy element mounting substrate 74 in which a dummy element 71 measuring 3 mm in length, 3 mm in width, and 200 μm in thickness is mounted on a glass substrate 72 via a bump 23 having a thickness T1 of 20 μm. The bump 23 is placed on one thickness-wise surface 30 of a dummy terminal 79 having a thickness T0 of 30 μm. This dummy element mounting substrate 74 includes a first gap 26 having a thickness T1 of 20 μm and a second gap 36 having a thickness T2 of 50 μm.

Step C: As shown in FIG. 3C, the sample sheet 61 is used to seal the dummy element 71 on the dummy element mounting substrate 74 using a vacuum platen press at a temperature of 65° C., a pressure of 0.1 MPa, a degree of vacuum of 1.6 kPa, and a press time of 1 minute to form an encapsulant 31 from the sample sheet 61.

Step D: As shown in FIG. 3D, the sealing body 31 is thermally cured by heating at 150° C. under atmospheric pressure for 1 hour to form a hardened body 41 from the sealing body 31.

Step E: As shown in the enlarged view of Figure 3D, using the side edge 75 of the dummy element 71 as a reference, measure the first hardened body penetration length Y1 of the hardened body 41 penetrating from the side edge 75 into the first gap 26, and the second highly hardened body penetration length Y2 of the hardened body 41 penetrating from the side edge 75 into the second gap 26.

The first hardened body penetration length Y1 and the second highly hardened body penetration length Y2 were evaluated according to the following criteria. The results are shown in Table 1.
◯: The first hardened body penetration length Y1 and the second hardened body penetration length Y2 were both 0 μm or more and 20 μm or less.
×: The first hardened body penetration length Y1 and the second hardened body penetration length Y2 were both greater than 30 μm or less than 0 μm.

In the evaluation, "minus" means that a space (unfilled portion) protruding outward from the side edge 75 of the dummy element 71 (see the thick dashed line in Figure 3D) is formed. The absolute value of the "minus" corresponds to the protruding length of that space.

The above invention is provided as an exemplary embodiment of the present invention, but this is merely an example and should not be interpreted as being limiting. Modifications of the present invention that are obvious to a person skilled in the art are included in the scope of the claims below.

Sealing resin sheets are used to seal elements.

1 Sealing resin sheet 21 Electronic element

Claims (8)

A sealing resin sheet containing a thermosetting resin, a layered silicate compound, and a thermoplastic resin for sealing an element,
A sealing resin sheet, characterized in that a ratio (A/α) of a mass A of the layered silicate compound to a mass α of the thermoplastic resin is 0.3 or more and 2.0 or less. The sealing resin sheet according to claim 1, characterized in that the content ratio B of the layered silicate compound is 3 mass% or more and 7 mass% or less. The sealing resin sheet described in claim 1, characterized in that the thermoplastic resin has a glass transition temperature Tg of -30°C or higher and -10°C or lower. The sealing resin sheet described in claim 2, characterized in that the thermoplastic resin has a glass transition temperature Tg of -30°C or higher and -10°C or lower. The layered silicate compound is characterized in that its surface is modified with an organic component.
The sealing resin sheet according to claim 1 . The layered silicate compound is characterized in that its surface is modified with an organic component.
The sealing resin sheet according to claim 2 . The layered silicate compound is characterized in that its surface is modified with an organic component.
The sealing resin sheet according to claim 3 . The layered silicate compound is characterized in that its surface is modified with an organic component.
The sealing resin sheet according to claim 4 .

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