JP7491223B2 - Encapsulating resin composition, electronic component device, and method for producing electronic component device - Google Patents

Description

The present invention relates to an encapsulating resin composition, an electronic component device, and a method for manufacturing an electronic component device.

The amount of transmission loss that occurs when radio waves transmitted for communication are converted into heat in a dielectric is expressed as the product of frequency, the square root of the dielectric constant, and the dielectric loss tangent. In other words, since the transmitted signal is more likely to turn into heat in proportion to the frequency, the higher the frequency band, the lower the dielectric properties required of the materials used in communication components in order to suppress transmission loss.

For example, Patent Documents 1 and 2 disclose a thermosetting resin composition containing an active ester resin as a curing agent for epoxy resin, which is said to be capable of keeping the dielectric tangent of the cured product low.

JP 2012-246367 A JP 2014-114352 A

In the field of information and communications, radio waves are becoming increasingly high frequency as the number of channels and the amount of information transmitted increase. Currently, research into the fifth generation mobile communications system is underway worldwide, with several candidate frequency bands in the range of approximately 30 GHz to 70 GHz being considered for use. As wireless communications will become mainstream in the future at such high frequencies, there is a demand for communication component materials with even lower dielectric tangents.

The embodiments of the present disclosure were made under the above circumstances.

The objective of the present disclosure is to provide an encapsulating resin composition having a low dielectric tangent of the cured product, an electronic component device encapsulated using the same, and a method for manufacturing an electronic component device encapsulated using the same.

Specific means for solving the above problems include the following aspects:

<1> An encapsulating resin composition comprising an epoxy resin, a curing agent including an active ester compound, and a thermosetting silicone.
<2> The encapsulating resin composition according to <1>, wherein the thermosetting silicone contains an epoxy group.
<3> The encapsulating resin composition according to <1> or <2>, wherein the thermosetting silicone has a structure in which a siloxane chain is branched.
<4> An electronic component device comprising: a support member; an element disposed on the support member; and a cured product of the encapsulating resin composition according to any one of <1> to <3> that encapsulates the element.
<5> A method for producing an electronic component device, comprising: a step of placing an element on a support member; and a step of encapsulating the element with the encapsulating resin composition according to any one of <1> to <4>.

According to the present disclosure, there is provided an encapsulating resin composition having a low dielectric tangent when cured, an electronic component device encapsulated using the same, and a method for manufacturing an electronic component device encapsulated using the same.

In the present disclosure, the term "step" includes not only a step that is independent of other steps, but also a step that cannot be clearly distinguished from other steps as long as the purpose of the step is achieved.
In the present disclosure, the numerical range indicated using "to" includes the numerical values before and after "to" as the minimum and maximum values, respectively.
In the numerical ranges described in the present disclosure in stages, the upper or lower limit value described in one numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. In addition, in the numerical ranges described in the present disclosure, the upper or lower limit value of the numerical range may be replaced with a value shown in the examples.
In the present disclosure, each component may contain multiple types of the corresponding substance. When multiple substances corresponding to each component are present in the composition, the content or amount of each component means the total content or amount of the multiple substances present in the composition, unless otherwise specified.
In the present disclosure, the particles corresponding to each component may include multiple types. When multiple types of particles corresponding to each component are present in the composition, the particle size of each component means the value for a mixture of the multiple types of particles present in the composition, unless otherwise specified.

<Encapsulating resin composition>
The encapsulating resin composition of the present disclosure is an encapsulating resin composition containing an epoxy resin, a curing agent including an active ester compound, and a thermosetting silicone.

As a result of the inventors' investigations, it was found that the cured product obtained by curing the encapsulating resin composition having the above-mentioned configuration has a lower dielectric tangent than the cured product of an encapsulating resin composition using a conventional epoxy resin and a curing agent. The reason for this is not entirely clear, but it is thought to be as follows.

First, the encapsulating resin composition of the present disclosure contains an active ester compound as a curing agent. Phenol curing agents, amine curing agents, and the like, which are generally used as curing agents for epoxy resins, generate secondary hydroxyl groups in a reaction with the epoxy resin. In contrast, an ester group is generated instead of a secondary hydroxyl group in a reaction between an epoxy resin and an active ester compound. Since an ester group has a lower polarity than a secondary hydroxyl group, the encapsulating resin composition of the present disclosure can keep the dielectric tangent of the cured product lower than an encapsulating resin composition that contains only a curing agent that generates secondary hydroxyl groups as a curing agent.

In this disclosure, an active ester compound refers to a compound that has one or more ester groups in one molecule that react with an epoxy group and has the effect of curing an epoxy resin.

Furthermore, the encapsulating resin composition of the present disclosure contains a thermosetting silicone. The cured product obtained by curing the encapsulating resin composition containing the thermosetting silicone has fine voids formed therein, which is thought to contribute to a further decrease in the dielectric tangent.

One possible reason why minute voids form inside the cured product obtained by curing an encapsulating resin composition containing thermosetting silicone is that, for example, when the encapsulating resin composition is heated to cure, the volume of the encapsulating resin composition expands, and the thermosetting silicone reacts with the epoxy resin or curing agent, resulting in a state in which voids are likely to form in the cured product when the volume shrinks upon cooling.

(Thermosetting silicone)
The type of thermosetting silicone contained in the encapsulating resin composition of the present disclosure is not particularly limited. From the viewpoint of forming fine voids in the cured product, it is preferable that the thermosetting silicone contains a functional group that can react with an epoxy resin or a curing agent. Examples of the functional group include an epoxy group, an amino group, a hydroxyl group, a cyano group, and the like, and among them, an epoxy group is preferable. The position of the functional group in the thermosetting silicone is not particularly limited. For example, it may be located at the end (one end or both ends) of the siloxane chain, or it may be located on a side chain.

From the viewpoint of forming fine voids in the cured product, it is preferable that the thermosetting silicone has a structure in which the siloxane chain is branched.

In one embodiment, the thermosetting silicone may be a silicone having the following bonds (a), (b) and (c):

In the bonds (a), (b) and (c), R ¹ each independently represents a substituted or unsubstituted monovalent hydrocarbon group having 1 to 12 carbon atoms, and X is a monovalent group containing a functional group capable of reacting with an epoxy resin or a curing agent.

Silicones having bonds (a), (b), and (c) have functional groups that can react with epoxy resins or curing agents, and have a structure in which the siloxane chain is branched, so that they can effectively form minute voids in the cured material of the encapsulating resin composition.

In the bonds (a), (b), and (c), examples of the substituted or unsubstituted monovalent hydrocarbon group having 1 to 12 carbon atoms represented by R ¹ include alkyl groups such as a methyl group, an ethyl group, a propyl group, a butyl group, an isopropyl group, an isobutyl group, a t-butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, and a 2-ethylhexyl group; alkenyl groups such as a vinyl group, an allyl group, a butenyl group, a pentenyl group, and a hexenyl group; aryl groups such as a phenyl group, a tolyl group, a xylyl group, a naphthyl group, and a biphenyl group; and aralkyl groups such as a benzyl group and a phenethyl group. Of these, a methyl group or a phenyl group is preferable.

In the bond (c), examples of the monovalent group containing a functional group that can react with the epoxy resin or curing agent represented by X include monovalent groups containing an epoxy group, an amino group, or a hydroxyl group. Specific examples include a 2,3-epoxypropyl group, a 3,4-epoxybutyl group, a 4,5-epoxypentyl group, a 2-glycidoxyethyl group, a 3-glycidoxypropyl group, a 4-glycidoxybutyl group, a 2-(3,4-epoxycyclohexyl)ethyl group, and a 3-(3,4-epoxycyclohexyl)propyl group, with the 3-glycidoxypropyl group being preferred.

In silicones having bonds (a), (b), and (c), the bonds (a), (b), and (c) may be arranged randomly or in blocks, but are preferably arranged randomly.

In silicones having bonds (a), (b), and (c), the structure of the terminal end of the siloxane chain is not particularly limited, but is preferably a substituted or unsubstituted monovalent hydrocarbon group having 1 to 12 carbon atoms, a hydroxyl group, or an alkoxy group.

Silicones having bonds (a), (b) and (c) may be obtained commercially or may be synthesized.

The functional group equivalent of the thermosetting silicone (epoxy equivalent in the case of an epoxy group) is preferably 500 to 4,000, and more preferably 1,000 to 2,500, from the viewpoints of the fluidity of the encapsulating resin composition and suppression of bleeding after curing.

The weight average molecular weight (Mw) of the thermosetting silicone is preferably 1,000 to 30,000, more preferably 2,000 to 20,000, and even more preferably 3,000 to 10,000. The weight average molecular weight (Mw) of the thermosetting silicone is measured by gel permeation chromatography (GPC) and converted using a standard polystyrene calibration curve.

From the viewpoint of the effect of reducing the dielectric tangent and the balance with other components, the content of the thermosetting silicone in the encapsulating resin composition is preferably 3 to 50 parts by weight, and more preferably 5 to 30 parts by weight, per 100 parts by weight of the epoxy resin component.

(Epoxy resin)
The type of epoxy resin contained in the encapsulating resin composition of the present disclosure is not particularly limited.
Specific examples of epoxy resins include novolac-type epoxy resins (phenol novolac-type epoxy resins, orthocresol novolac-type epoxy resins, etc.) which are obtained by epoxidizing a novolac resin obtained by condensing or co-condensing at least one phenolic compound selected from the group consisting of phenolic compounds such as phenol, cresol, xylenol, resorcin, catechol, bisphenol A, bisphenol F, etc., and naphthol compounds such as α-naphthol, β-naphthol, dihydroxynaphthalene, etc., with an aliphatic aldehyde compound such as formaldehyde, acetaldehyde, propionaldehyde, etc., under an acidic catalyst; and triphenylmethane-type phenolic resins which are obtained by condensing or co-condensing the above-mentioned phenolic compound with an aromatic aldehyde compound such as benzaldehyde, salicylaldehyde, etc., under an acidic catalyst. diphenylmethane-type epoxy resins; copolymer epoxy resins obtained by epoxidizing novolak resins obtained by co-condensing the above-mentioned phenol compounds and naphthol compounds with aldehyde compounds under an acidic catalyst; diphenylmethane-type epoxy resins which are diglycidyl ethers of bisphenol A, bisphenol F, etc.; biphenyl-type epoxy resins which are diglycidyl ethers of alkyl-substituted or unsubstituted biphenols; stilbene-type epoxy resins which are diglycidyl ethers of stilbene-based phenol compounds; sulfur-containing epoxy resins which are diglycidyl ethers of bisphenol S, etc.; epoxy resins which are glycidyl ethers of alcohols such as butanediol, polyethylene glycol, and polypropylene glycol; glycidyl ester-type epoxy resins which are glycidyl esters of polyvalent carboxylic acid compounds such as phthalic acid, isophthalic acid, and tetrahydrophthalic acid. glycidylamine-type epoxy resins in which active hydrogen attached to nitrogen atoms of aniline, diaminodiphenylmethane, isocyanuric acid, etc. is replaced with a glycidyl group; dicyclopentadiene-type epoxy resins in which a co-condensed resin of dicyclopentadiene and a phenol compound is epoxidized; alicyclic epoxy resins such as vinylcyclohexene diepoxide, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and 2-(3,4-epoxy)cyclohexyl-5,5-spiro(3,4-epoxy)cyclohexane-m-dioxane in which an olefin bond in a molecule is epoxidized; paraxylylene-modified epoxy resins which are glycidyl ethers of paraxylylene-modified phenolic resins; metaxylylene-modified epoxy resins which are glycidyl ethers of metaxylylene-modified phenolic resins; terpene-modified phenolic resins Terpene-modified epoxy resins are glycidyl ethers of phenol resins; dicyclopentadiene-modified epoxy resins are glycidyl ethers of dicyclopentadiene-modified phenol resins; cyclopentadiene-modified epoxy resins are glycidyl ethers of cyclopentadiene-modified phenol resins; polycyclic aromatic ring-modified epoxy resins are glycidyl ethers of polycyclic aromatic ring-modified phenol resins; naphthalene-type epoxy resins are glycidyl ethers of naphthalene ring-containing phenol resins; halogenated phenol novolac-type epoxy resins; hydroquinone-type epoxy resins; trimethylolpropane-type epoxy resins; linear aliphatic epoxy resins obtained by oxidizing olefin bonds with peracids such as peracetic acid; aralkyl-type epoxy resins obtained by epoxidizing aralkyl-type phenol resins such as phenol aralkyl resins and naphthol aralkyl resins; and the like. Furthermore, epoxy-oxidized acrylic resins and the like can also be mentioned as epoxy resins. These epoxy resins may be used alone or in combination of two or more.

The epoxy equivalent (molecular weight/number of epoxy groups) of the epoxy resin is not particularly limited. From the viewpoint of the balance of various properties such as moldability, reflow resistance, and electrical reliability, it is preferably 100 g/eq to 1000 g/eq, and more preferably 150 g/eq to 500 g/eq.

The epoxy equivalent of the epoxy resin shall be the value measured in accordance with JIS K 7236:2009.

When the epoxy resin is solid, its softening point or melting point is not particularly limited. From the viewpoints of moldability and reflow resistance, it is preferably 40°C to 180°C, and from the viewpoint of handleability when preparing the encapsulating resin composition, it is more preferably 50°C to 130°C.

The melting point or softening point of the epoxy resin shall be a value measured by differential scanning calorimetry (DSC) or a method conforming to JIS K 7234:1986 (ring and ball method).

From the standpoints of strength, fluidity, heat resistance, moldability, etc., the content of epoxy resin in the encapsulating resin composition is preferably 0.5% by mass to 50% by mass, and more preferably 2% by mass to 30% by mass.

(Hardening agent)
The encapsulating resin composition of the present disclosure includes at least an active ester compound as a curing agent. The encapsulating resin composition of the present disclosure may include a curing agent other than the active ester compound.

As described above, the encapsulating resin composition of the present disclosure can maintain the dielectric tangent of the cured product low by using an active ester compound as a curing agent.
In addition, the polar group in the cured product increases the water absorption of the cured product, and by using an active ester compound as a curing agent, the polar group concentration of the cured product can be reduced, and the water absorption of the cured product can be reduced. By reducing the water absorption of the cured product, that is, by reducing the content of H ₂ O, which is a polar molecule, the dielectric tangent of the cured product can be further reduced. The water absorption of the cured product is preferably 0% to 0.35%, more preferably 0% to 0.30%, and even more preferably 0% to 0.25%. Here, the water absorption of the cured product is the mass increase rate determined by a pressure cooker test (121°C, 2.1 atm, 24 hours).

There are no particular limitations on the type of active ester compound, as long as it is a compound that has one or more ester groups in the molecule that react with an epoxy group.

Examples of active ester compounds include phenol ester compounds, thiophenol ester compounds, N-hydroxyamine ester compounds, and esters of heterocyclic hydroxy compounds.

Examples of active ester compounds include ester compounds obtained from at least one of an aliphatic carboxylic acid and an aromatic carboxylic acid and at least one of an aliphatic hydroxy compound and an aromatic hydroxy compound. Ester compounds that use an aliphatic compound as a polycondensation component tend to have excellent compatibility with epoxy resins due to the presence of an aliphatic chain. Ester compounds that use an aromatic compound as a polycondensation component tend to have excellent heat resistance due to the presence of an aromatic ring.

Specific examples of active ester compounds include aromatic esters obtained by condensation reaction between aromatic carboxylic acids and phenolic hydroxyl groups. Among them, aromatic esters obtained by condensation reaction between aromatic carboxylic acids and phenolic hydroxyl groups using a mixture of an aromatic carboxylic acid component in which 2 to 4 hydrogen atoms of an aromatic ring such as benzene, naphthalene, biphenyl, diphenylpropane, diphenylmethane, diphenylether, or diphenylsulfonic acid are substituted with carboxyl groups, a monohydric phenol in which one hydrogen atom of the aromatic ring is substituted with a hydroxyl group, and a polyhydric phenol in which 2 to 4 hydrogen atoms of the aromatic ring are substituted with a hydroxyl group as raw materials are preferred. In other words, aromatic esters having structural units derived from the aromatic carboxylic acid component, structural units derived from the monohydric phenol, and structural units derived from the polyhydric phenol are preferred.

Specific examples of active ester compounds include the active ester resin described in JP 2012-246367 A, which has a structure obtained by reacting a phenolic resin having a molecular structure in which phenolic compounds are bonded via alicyclic hydrocarbon groups with an aromatic dicarboxylic acid or its halide and an aromatic monohydroxy compound. As the active ester resin, a compound represented by the following structural formula (1) is preferred.

In structural formula (1), ^R1 is an alkyl group having 1 to 4 carbon atoms; X is a benzene ring, a naphthalene ring, a benzene ring or a naphthalene ring substituted with an alkyl group having 1 to 4 carbon atoms, or a biphenyl group; Y is a benzene ring, a naphthalene ring, or a benzene ring or a naphthalene ring substituted with an alkyl group having 1 to 4 carbon atoms; k is 0 or 1; and n represents the average number of repetitions and is 0.25 to 1.5.

Specific examples of the compound represented by structural formula (1) include the following exemplary compounds (1-1) to (1-10). In the structural formula, t-Bu is a tert-butyl group.

Other specific examples of active ester compounds include the compound represented by the following structural formula (2) and the compound represented by the following structural formula (3), which are described in JP 2014-114352 A.

In structural formula (2), ^R1 and ^R2 each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms; Z represents an ester-forming structural moiety (z1) selected from the group consisting of a benzoyl group, a naphthoyl group, a benzoyl group or a naphthoyl group substituted with an alkyl group having 1 to 4 carbon atoms, and an acyl group having 2 to 6 carbon atoms, or a hydrogen atom (z2); and at least one of Z's is an ester-forming structural moiety (z1).

In structural formula (3), ^R1 and ^R2 each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms; Z represents an ester-forming structural moiety (z1) selected from the group consisting of a benzoyl group, a naphthoyl group, a benzoyl group or a naphthoyl group substituted with an alkyl group having 1 to 4 carbon atoms, and an acyl group having 2 to 6 carbon atoms, or a hydrogen atom (z2); and at least one of the Z's is an ester-forming structural moiety (z1).

Specific examples of compounds represented by structural formula (2) include the following exemplary compounds (2-1) to (2-6).

Specific examples of compounds represented by structural formula (3) include the following exemplary compounds (3-1) to (3-6).

Commercially available products may be used as the active ester compound. Commercially available products of the active ester compound include "EXB9451", "EXB9460", "EXB9460S", and "HPC-8000-65T" (manufactured by DIC Corporation) as active ester compounds containing a dicyclopentadiene-type diphenol structure; "EXB9416-70BK", "EXB-8", and "EXB-9425" (manufactured by DIC Corporation) as active ester compounds containing an aromatic structure; "DC808" (manufactured by Mitsubishi Chemical Corporation) as an active ester compound containing an acetylated product of phenol novolac; and "YLH1026" (manufactured by Mitsubishi Chemical Corporation) as an active ester compound containing a benzoylated product of phenol novolac.

Active ester compounds may be used alone or in combination of two or more.

The ester equivalent of the active ester compound is not particularly limited. From the viewpoint of the balance of various properties such as moldability, reflow resistance, and electrical reliability, 150 g/eq to 400 g/eq is preferable, 170 g/eq to 300 g/eq is more preferable, and 200 g/eq to 250 g/eq is even more preferable.

The ester equivalent of an active ester compound is a value measured by a method conforming to JIS K 0070:1992.

From the viewpoint of keeping the dielectric tangent of the cured product low, the equivalent ratio of the epoxy resin to the active ester compound (ester group/epoxy group) is preferably 0.9 or more, more preferably 0.95 or more, and even more preferably 0.97 or more.
From the viewpoint of keeping the amount of unreacted active ester compound low, the equivalent ratio of the epoxy resin to the active ester compound (ester group/epoxy group) is preferably 1.1 or less, more preferably 1.05 or less, and even more preferably 1.03 or less.

The curing agent may contain other curing agents other than the active ester compound. In this case, the type of other curing agent is not particularly limited and can be selected according to the desired properties of the encapsulating resin composition. Examples of other curing agents include phenol curing agents, amine curing agents, acid anhydride curing agents, polymercaptan curing agents, polyaminoamide curing agents, isocyanate curing agents, blocked isocyanate curing agents, etc.

Specific examples of phenolic hardeners include polyhydric phenol compounds such as resorcin, catechol, bisphenol A, bisphenol F, and substituted or unsubstituted biphenol; novolak-type phenolic resins obtained by condensing or co-condensing at least one phenolic compound selected from the group consisting of phenolic compounds such as phenol, cresol, xylenol, resorcin, catechol, bisphenol A, bisphenol F, phenylphenol, and aminophenol, and naphthol compounds such as α-naphthol, β-naphthol, and dihydroxynaphthalene, with aldehyde compounds such as formaldehyde, acetaldehyde, and propionaldehyde, under an acid catalyst; and novolak-type phenolic resins synthesized from the above phenolic compounds and dimethoxy-para-xylene, bis(methoxymethyl)biphenyl, etc. Examples of the phenol curing agent include aralkyl-type phenolic resins such as phenol aralkyl resins and naphthol aralkyl resins, paraxylylene-modified phenolic resins, metaxylylene-modified phenolic resins, melamine-modified phenolic resins, terpene-modified phenolic resins, dicyclopentadiene-type phenolic resins and dicyclopentadiene-type naphthol resins synthesized by copolymerization of the above-mentioned phenolic compounds and dicyclopentadiene, cyclopentadiene-modified phenolic resins, polycyclic aromatic ring-modified phenolic resins, biphenyl-type phenolic resins, triphenylmethane-type phenolic resins obtained by condensing or co-condensing the above-mentioned phenolic compounds with aromatic aldehyde compounds such as benzaldehyde and salicylaldehyde under an acid catalyst, and phenolic resins obtained by copolymerizing two or more of these. These phenolic curing agents may be used alone or in combination of two or more.

The functional group equivalent of other hardeners (hydroxyl group equivalent in the case of phenolic hardeners) is not particularly limited. From the viewpoint of the balance of various properties such as moldability, reflow resistance, and electrical reliability, it is preferably 70 g/eq to 1000 g/eq, and more preferably 80 g/eq to 500 g/eq.

The functional group equivalent of other hardeners (hydroxyl group equivalent in the case of phenolic hardeners) shall be the value measured by a method conforming to JIS K 0070:1992.

When the curing agent is a solid, its softening point or melting point is not particularly limited. From the viewpoints of moldability and reflow resistance, it is preferably 40°C to 180°C, and from the viewpoint of handleability during the production of the encapsulating resin composition, it is more preferably 50°C to 130°C.

The melting point or softening point of the curing agent shall be a value measured in the same manner as the melting point or softening point of the epoxy resin.

The equivalent ratio of the epoxy resin to all curing agents (active ester compounds and other curing agents), i.e., the ratio of the number of functional groups in the curing agent to the number of functional groups in the epoxy resin (number of functional groups in the curing agent/number of functional groups in the epoxy resin), is not particularly limited. From the viewpoint of keeping the amount of unreacted components low, it is preferably set in the range of 0.5 to 2.0, and more preferably in the range of 0.6 to 1.3. From the viewpoint of moldability and reflow resistance, it is even more preferable to set it in the range of 0.8 to 1.2.

The content of the active ester compound relative to the total mass of the active ester compound and other curing agents is preferably 80% by mass or more, more preferably 85% by mass or more, and even more preferably 90% by mass or more, from the viewpoint of keeping the dielectric tangent of the cured product low.

The total content of the epoxy resin and the active ester compound relative to the total mass of the epoxy resin, the active ester compound and other curing agents is preferably 80% by mass or more, more preferably 85% by mass or more, and even more preferably 90% by mass or more, from the viewpoint of keeping the dielectric tangent of the cured product low.

(Cure Accelerator)
The encapsulating resin composition may contain a curing accelerator. The type of the curing accelerator is not particularly limited and can be selected depending on the type of epoxy resin or curing agent, the desired properties of the encapsulating resin composition, and the like.

Examples of hardening accelerators include diazabicycloalkenes such as 1,5-diazabicyclo[4.3.0]nonene-5 (DBN) and 1,8-diazabicyclo[5.4.0]undecene-7 (DBU), cyclic amidine compounds such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, and 2-heptadecylimidazole; derivatives of the cyclic amidine compounds; phenol novolac salts of the cyclic amidine compounds or their derivatives; and mixtures of these compounds with maleic anhydride. compounds having intramolecular polarization obtained by adding a compound having a π bond, such as quinone compounds, such as diazophenylmethane, quinone compounds, such as phenyl-1,4-benzoquinone, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, and phenyl-1,4-benzoquinone; tetraphenylborate salt of DBU, tetraphenylborate salt of DBN, Cyclic amidinium compounds such as tetraphenylborate salt of 2-ethyl-4-methylimidazole and tetraphenylborate salt of N-methylmorpholine; tertiary amine compounds such as pyridine, triethylamine, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol; derivatives of the above tertiary amine compounds; ammonium salt compounds such as tetra-n-butylammonium acetate, tetra-n-butylammonium phosphate, tetraethylammonium acetate, tetra-n-hexylammonium benzoate, and tetrapropylammonium hydroxide; triphenylphosphine, diphenyl(p-tolyl)phosphine, tris(alkylphenyl)phosphine, tris(alkoxyphenyl)phosphine, tris(alkyl.alkoxyphenyl)phosphine, tris(dialkylphenyl)phosphine, tris(trialkylphenyl)phosphine, tris(tetraalkylphenyl)phosphine, )phosphine, tris(dialkoxyphenyl)phosphine, tris(trialkoxyphenyl)phosphine, tris(tetraalkoxyphenyl)phosphine, trialkylphosphine, dialkylarylphosphine, alkyldiarylphosphine, and other tertiary phosphines; phosphine compounds such as complexes of the above-mentioned tertiary phosphines with organic borons; compounds having intramolecular polarization obtained by adding the above-mentioned tertiary phosphines or the above-mentioned phosphine compounds to maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, phenyl-1,4-benzoquinone, and other quinone compounds, diazophenylmethane, and other compounds having a π bond; the above-mentioned tertiary phosphines or the above-mentioned phosphine compounds to 4-bromophenol, 3-bromophenol, 2-bromophenol, 4-chlorophenol, and other compounds having an intramolecular polarization. , 3-chlorophenol, 2-chlorophenol, 4-iodophenol, 3-iodophenol, 2-iodophenol, 4-bromo-2-methylphenol, 4-bromo-3-methylphenol, 4-bromo-2,6-dimethylphenol, 4-bromo-3,5-dimethylphenol, 4-bromo-2,6-di-tert-butylphenol, 4-chloro-1-naphthol, 1-bromo-2-naphthol, 6-bromo-2-naphthol, 4-bromo-4'-hydroxybiphenyl, or other halogenated phenol compounds, followed by a dehydrohalogenation step, and the like, which have intramolecular polarization; tetra-substituted phosphonium compounds such as tetraphenylphosphonium, tetra-substituted phosphonium compounds and tetra-substituted borates having no phenyl group bonded to a boron atom, such as tetra-p-tolylborate, and the like; salts of tetraphenylphosphonium compounds and phenol compounds, and salts of tetraalkylphosphonium compounds and partial hydrolysates of aromatic carboxylic acid anhydrides.

When the encapsulating resin composition contains a curing accelerator, the amount is preferably 0.1 to 30 parts by mass, and more preferably 1 to 15 parts by mass, per 100 parts by mass of the resin component (total amount of epoxy resin and curing agent). When the amount of the curing accelerator is 0.1 parts by mass or more per 100 parts by mass of the resin component, it tends to cure well in a short time. When the amount of the curing accelerator is 30 parts by mass or less per 100 parts by mass of the resin component, it tends to cure not too quickly and to produce a good molded product.

(Inorganic filler)
The encapsulating resin composition of the present disclosure may contain an inorganic filler. The type of inorganic filler is not particularly limited. Specific examples of inorganic materials include fused silica, crystalline silica, glass, alumina, talc, clay, mica, boron nitride, and aluminum nitride. An inorganic filler having a flame retardant effect may be used. Examples of inorganic fillers having a flame retardant effect include aluminum hydroxide, magnesium hydroxide, magnesium oxide, composite metal hydroxides such as composite hydroxides of magnesium and zinc, and zinc borate.

Among inorganic fillers, silica such as fused silica is preferred from the viewpoint of reducing the linear expansion coefficient, and alumina is preferred from the viewpoint of high thermal conductivity. One type of inorganic filler may be used alone, or two or more types may be used in combination. Inorganic fillers may be in the form of powder, beads made by sphering powder, fibers, etc.

When the inorganic filler is particulate, its average particle size is not particularly limited. For example, the average particle size is preferably 0.2 μm to 100 μm, and more preferably 0.5 μm to 50 μm. When the average particle size is 0.2 μm or more, the increase in viscosity of the encapsulating resin composition tends to be further suppressed. When the average particle size is 100 μm or less, the filling property tends to be further improved. The average particle size of the inorganic filler is determined as the volume average particle size (D50) using a laser scattering diffraction particle size distribution measuring device.

The content of the inorganic filler contained in the encapsulating resin composition is not particularly limited. From the viewpoint of fluidity and strength, it is preferably 30% to 90% by volume of the entire encapsulating resin composition, more preferably 35% to 80% by volume, and even more preferably 40% to 70% by volume. When the content of the inorganic filler is 30% by volume or more of the entire encapsulating resin composition, the properties such as the thermal expansion coefficient, thermal conductivity, and elastic modulus of the cured product tend to be further improved. When the content of the inorganic filler is 90% by volume or less of the entire encapsulating resin composition, the increase in the viscosity of the encapsulating resin composition is suppressed, the fluidity is further improved, and the moldability tends to be better.

[Various additives]
In addition to the above-mentioned components, the encapsulating resin composition may contain various additives such as coupling agents, ion exchangers, release agents, flame retardants, colorants, etc., as exemplified below. The encapsulating resin composition may contain various additives known in the art, as necessary, in addition to the additives exemplified below.

(Coupling Agent)
The encapsulating resin composition may contain a coupling agent. From the viewpoint of increasing the adhesion between the resin component and the inorganic filler, the encapsulating resin composition preferably contains a coupling agent. Examples of the coupling agent include known coupling agents such as silane-based compounds such as epoxysilane, mercaptosilane, aminosilane, alkylsilane, ureidosilane, and vinylsilane, titanium-based compounds, aluminum chelate compounds, and aluminum/zirconium-based compounds.

When the encapsulating resin composition contains a coupling agent, the amount of the coupling agent is preferably 0.05 parts by mass to 10 parts by mass, and more preferably 0.1 parts by mass to 5 parts by mass, per 100 parts by mass of the inorganic filler. When the amount of the coupling agent is 0.05 parts by mass or more per 100 parts by mass of the inorganic filler, the adhesion to the frame tends to be further improved. When the amount of the coupling agent is 10 parts by mass or less per 100 parts by mass of the inorganic filler, the moldability of the package tends to be further improved.

(Ion exchanger)
The encapsulating resin composition may contain an ion exchanger. The encapsulating resin composition preferably contains an ion exchanger from the viewpoint of improving the moisture resistance and high-temperature storage characteristics of an electronic component device including an element to be encapsulated. The ion exchanger is not particularly limited, and a conventionally known ion exchanger can be used. Specific examples include hydrotalcite compounds and hydrous oxides of at least one element selected from the group consisting of magnesium, aluminum, titanium, zirconium, and bismuth. The ion exchanger may be used alone or in combination of two or more types. Among them, hydrotalcite represented by the following general formula (A) is preferred.

Mg _{(1-X) AlX} (OH) ₂ ( _CO3 ) _{X/ 2.mH2O} ...(A)
(0<X≦0.5, m is a positive number)

When the encapsulating resin composition contains an ion exchanger, the content is not particularly limited as long as it is a sufficient amount to capture ions such as halogen ions. For example, it is preferably 0.1 to 30 parts by mass, and more preferably 1 to 10 parts by mass, per 100 parts by mass of the resin component (total amount of epoxy resin and curing agent).

(Release agent)
The encapsulating resin composition may contain a mold release agent from the viewpoint of obtaining good releasability from the mold during molding. The mold release agent is not particularly limited, and a conventionally known one may be used. Specific examples include carnauba wax, higher fatty acids such as montanic acid and stearic acid, higher fatty acid metal salts, ester waxes such as montanic acid esters, polyolefin waxes such as oxidized polyethylene and non-oxidized polyethylene, etc. The mold release agent may be used alone or in combination of two or more kinds.

When the encapsulating resin composition contains a release agent, the amount is preferably 0.01 to 10 parts by mass, and more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the resin component (total amount of epoxy resin and curing agent). When the amount of release agent is 0.01 parts by mass or more per 100 parts by mass of the resin component, sufficient releasability tends to be obtained. When the amount is 10 parts by mass or less, better adhesion tends to be obtained.

(Flame retardants)
The encapsulating resin composition may contain a flame retardant. The flame retardant is not particularly limited, and a conventionally known flame retardant may be used. Specific examples include organic or inorganic compounds containing halogen atoms, antimony atoms, nitrogen atoms, or phosphorus atoms, metal hydroxides, etc. The flame retardant may be used alone or in combination of two or more.

When the encapsulating resin composition contains a flame retardant, the amount is not particularly limited as long as it is sufficient to obtain the desired flame retardant effect. For example, it is preferably 1 to 30 parts by mass, and more preferably 2 to 20 parts by mass, per 100 parts by mass of the resin component (total amount of epoxy resin and curing agent).

(Coloring Agent)
The encapsulating resin composition may contain a colorant. Examples of the colorant include known colorants such as carbon black, organic dyes, organic pigments, titanium oxide, red lead, and red iron oxide. The content of the colorant can be appropriately selected depending on the purpose. The colorant may be used alone or in combination of two or more.

(Method for preparing encapsulating resin composition)
The method for preparing the encapsulating resin composition is not particularly limited. A typical method is to thoroughly mix the components in a predetermined amount with a mixer or the like, melt-knead them with a mixing roll, an extruder, or the like, cool them, and pulverize them. More specifically, for example, a method is to uniformly stir and mix the predetermined amounts of the above-mentioned components, knead them with a kneader, roll, extruder, or the like that has been heated to 70°C to 140°C in advance, cool them, and pulverize them.

The encapsulating resin composition is preferably solid at room temperature and normal pressure (e.g., 25°C, atmospheric pressure). When the encapsulating resin composition is solid, the shape is not particularly limited, and examples include powder, granules, tablets, etc. When the encapsulating resin composition is in tablet form, it is preferable from the viewpoint of handleability that the dimensions and mass are set to be suitable for the molding conditions of the package.

<Electronic component device>
An electronic component device according to one embodiment of the present disclosure includes an element and a cured product of the encapsulating resin composition according to the present disclosure encapsulating the element.

Examples of electronic component devices include devices obtained by mounting elements (active elements such as semiconductor chips, transistors, diodes, and thyristors, and passive elements such as capacitors, resistors, and coils) on a support member such as a lead frame, a pre-wired tape carrier, a wiring board, glass, a silicon wafer, or an organic substrate, and encapsulating the resulting element portion with an encapsulating resin composition.
More specifically, the following packages are available: DIP (Dual Inline Package), PLCC (Plastic Leaded Chip Carrier), QFP (Quad Flat Package), SOP (Small Outline Package), SOJ (Small Outline J-lead package), TSOP (Thin Small Outline Package), TQFP (Thin Quad Flat Package), which have a structure in which an element is fixed on a lead frame, and terminals of the element such as bonding pads and leads are connected by wire bonding, bumps, or the like, and then encapsulated by transfer molding or the like using an encapsulating resin composition. General resin-sealed ICs such as a TCP (Tape Carrier Package); a TCP (Tape Carrier Package) having a structure in which an element connected to a tape carrier by a bump is sealed with an encapsulating resin composition; a COB (Chip On Board) module, hybrid IC, multi-chip module, etc. having a structure in which an element connected to wiring formed on a support member by wire bonding, flip chip bonding, solder, etc. is sealed with an encapsulating resin composition; a BGA (Ball Grid Array), CSP (Chip Size Package), MCP (Multi Chip Package), etc. having a structure in which an element is mounted on the surface of a support member having a terminal for wiring board connection formed on the back side, the element and the wiring formed on the support member are connected by bump or wire bonding, and then the element is sealed with an encapsulating resin composition. The encapsulating resin composition can also be suitably used in printed wiring boards.

<Method of Manufacturing Electronic Component Device>
The method for producing an electronic component device of the present disclosure includes a step of placing an element on a support member, and a step of encapsulating the element with the encapsulating resin composition of the present disclosure.

The method for carrying out each of the above steps is not particularly limited, and can be carried out by a general method. In addition, the types of support members and elements used in the manufacture of electronic component devices are not particularly limited, and support members and elements commonly used in the manufacture of electronic component devices can be used.

Methods for encapsulating elements using the encapsulating resin composition of the present disclosure include low-pressure transfer molding, injection molding, compression molding, etc. Of these, low-pressure transfer molding is the most common.

The above-mentioned embodiments are explained in detail below using examples, but the scope of the above-mentioned embodiments is not limited to these examples.

<Preparation of Encapsulating Resin Composition>
The components shown below were mixed in the blending ratios (parts by mass) shown in Table 1 to prepare encapsulating resin compositions of Examples and Comparative Examples.

Epoxy resin 1: biphenylene aralkyl type epoxy resin, epoxy equivalent 275 g/eq (Nippon Kayaku Co., Ltd., product name "NC-3000")
Epoxy resin 2: biphenyl type epoxy resin, epoxy equivalent 192 g/eq (Mitsubishi Chemical Corporation, product name "YX-4000")

- Active ester compounds: Active ester compounds (DIC Corporation)

- Thermosetting silicone: Epoxy-modified silicone having the bonds (a), (b) and (c) described above (Dow Corning Toray Silicone Co., Ltd.)

・Cure accelerator: Triphenylphosphine/p-benzoquinone adduct

Filler: fused silica (Denka Company, volume average particle size 10 μm)

Coupling agent 1: N-phenyl-3-aminopropyltrimethoxysilane (Shin-Etsu Chemical Co., Ltd., product name "KBM-573")
Coupling agent 2: 3-mercaptopropyltrimethoxysilane (Shin-Etsu Chemical Co., Ltd., product name "KBM-803")
Release agent: Montan acid ester wax (Clariant Japan Co., Ltd., product name "HW-E")
Colorant: Carbon black (Mitsubishi Chemical Corporation, product name "MA600")

(Dielectric constant and dielectric loss tangent)
The encapsulating resin composition was charged into a transfer molding machine and molded under the conditions of a mold temperature of 175°C, molding pressure of 75 tons, and 120 seconds, and then post-cured at 175°C for 6 hours to obtain a plate-shaped cured product (length 130 mm, width 13 mm, thickness 0.8 mm). The plate-shaped cured product was then cut into a rectangular column of 0.8 mm square and 80 mm long. The rectangular column was used as a test piece to measure the relative dielectric constant and dielectric loss tangent at a temperature of 25±3°C and 20 GHz using a dielectric constant measuring device (Agilent, product name "Network Analyzer N5227A").

(Hot hardness)
The encapsulating resin composition was charged into a transfer molding machine and molded under the conditions of a mold temperature of 180° C., a molding pressure of 6.9 MPa, and a curing time of 90 seconds to obtain a disk-shaped molded product (diameter 40 mm, thickness 5 mm). The Shore D hardness was measured within 10 seconds after the mold was released using a Shore D hardness tester.

As shown in Table 1, the encapsulating resin composition of the example containing an active ester compound as a curing agent and a thermosetting silicone had a lower dielectric tangent value of the cured product than the encapsulating resin composition of the comparative example containing an active ester compound as a curing agent but not a thermosetting silicone.

Claims (5)

An encapsulating resin composition in the form of a powder, granules or tablets, which contains an epoxy resin, a curing agent containing an active ester compound, and a thermosetting silicone. The encapsulating resin composition contains an epoxy resin, a curing agent containing an active ester compound, and a thermosetting silicone having a functional group equivalent of 500 to 4,000 and having the following bonds (a), (b), and (c):

In the bonds (a), (b) and (c), R ¹ each independently represents a substituted or unsubstituted monovalent hydrocarbon group having 1 to 12 carbon atoms, and X is a monovalent group containing a functional group capable of reacting with an epoxy resin or a curing agent. The encapsulating resin composition according to claim 1 or 2, wherein the thermosetting silicone has a structure in which the siloxane chain is branched. A support member;
An element disposed on the support member;
A cured product of the encapsulating resin composition according to any one of claims 1 to 3 which encapsulates the element; and
An electronic component device comprising: placing the element on a support member;
a step of encapsulating the element with the encapsulating resin composition according to any one of claims 1 to 3 ;
A method for manufacturing an electronic component device comprising the steps of: