TW201802173A - Epoxy resin composition and semiconductor device - Google Patents

Abstract

The epoxy resin composition comprises an epoxy resin (A), a phenol resin (B), a curing accelerator (C), and a lactone compound having at least one or more hydroxyl groups in lactone ring A and containing a specific structural unit.

Description

Epoxy resin composition and semiconductor device

The invention relates to an epoxy resin composition and a semiconductor device.

In recent years, in the market trend of miniaturization, weight reduction, and high functionality of electronic equipment, the high integration and thinness of semiconductor devices are being promoted year by year. When the surface mounting of semiconductor devices is promoted, semiconductor devices are installed in areas. The transition has been made: the area-mounted semiconductor device is obtained by replacing semiconductor lead frames used in the past by mounting semiconductor elements on substrates such as organic substrates or ceramic substrates, and electrically connecting the substrates and semiconductor elements by connecting members. The semiconductor element and the connection member are molded and sealed by a mold material. Examples of the area-mount type semiconductor device include a BGA (Ball Grid Array) and a CSP (Chip Scale Packaging) which is further miniaturized.

The sealing material used in such an area-mount type semiconductor device is appropriately selected from materials such as an epoxy resin, a curing agent, and a curing accelerator according to the requirements of various purposes. As such a technique, the epoxy resin composition described in patent document 1, for example is mentioned.

According to this document, it is described that a cured product of an epoxy resin having a small curing shrinkage and a high elastic modulus can be obtained by combining 6-membered cyclic lactones. It is described that a 6-membered cyclic lactone having no hydroxyl group is used in this epoxy resin composition (paragraphs 0057 and 0117 described in Patent Document 1).

[Patent Document 1]: Japanese Patent Application Publication No. 2013-32510

However, the inventors have confirmed through research that the epoxy resin composition described in the above-mentioned literature needs to be improved from a potential point of view.

The present inventors focused on improving the potential and conducted various studies on compounds capable of controlling the curing characteristics of the curing accelerator.

The present inventors have completed the present invention from the findings of these various studies, that is, by using a lactone compound having a hydroxy group bonded to a lactone ring, the present invention can be compared with an epoxy resin using a curing accelerator. The composition increases the potential.

The detailed mechanism is not clear, but it is believed that the hydroxyl group bonded to the lactone ring can increase the potential by coordinating with the curing accelerator or ionic bonding.

According to the present invention, there is provided an epoxy resin composition comprising: an epoxy resin (A); a phenol resin (B); a curing accelerator (C); and a lactone compound having at least one lactone ring A The above hydroxyl group contains the following structural unit (1).

(In the above structural unit (1), m represents an integer of 1 or 2, and n represents an integer of 1 to 6. B represents a monovalent or divalent organic group. Ra independently represents a hydrogen atom, a hydroxyl group, and an alkyl group. N When it is 2 or more, Ra may be bonded to each other to form a ring.)

Furthermore, according to the present invention, there can be provided a semiconductor device including: a semiconductor element; and a sealing member sealing the semiconductor element, the sealing member being formed of a cured product of the epoxy resin composition.

[Effect of the invention]

According to the present invention, it is possible to provide an epoxy resin composition having excellent potential and a semiconductor device using the same.

10‧‧‧ substrate

12‧‧‧welding ball

20‧‧‧Semiconductor element

22‧‧‧ bump

30‧‧‧sealing resin layer

32‧‧‧ primer

100‧‧‧ semiconductor device

102‧‧‧ Structure

The above-mentioned object and other objects, features, and advantages will become more apparent by a suitable embodiment described below and the accompanying drawings.

FIG. 1 is a cross-sectional view showing an example of a semiconductor device in this embodiment.

FIG. 2 is a cross-sectional view showing an example of a structure in the present embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in all drawings, the same constituent elements are assigned the same reference numerals, and descriptions thereof are appropriately omitted.

The epoxy resin composition according to this embodiment is a lactone compound containing an epoxy resin (A), a phenol resin (B), a curing accelerator (C), and a lactone ring A having at least one hydroxyl group.

In the epoxy resin composition of this embodiment, a ring bond with a lactone can be used. A hydroxy lactone compound. Therefore, an epoxy resin composition having excellent potential can be realized. In addition, the structure of the lactone compound or its content can be appropriately controlled to improve the balance of potentiality, fluidity, and storage stability.

From the perspective of potentiality, the present inventors focused on the current epoxy resin composition to be improved, and conducted various studies based on this focus. As a result, the present inventors noticed the existence of a compound capable of controlling the curing characteristics of the curing accelerator, and as a result of further in-depth research, they found that the epoxy resin composition using the curing accelerator can be used in Hydroxy lactone compounds are bonded to the lactone ring to increase the potential.

The detailed mechanism is not clear, but it can be estimated as follows. In this embodiment, since the lactone compound has a hydroxyl group bonded to a lactone ring, it has a low pKa (acid dissociation constant). The lactone compound becomes an anion, and the curing accelerator becomes a cation. Therefore, the hydroxyl group bonded to the lactone ring is coordinated or ionic bonded to the curing accelerator. It is thought that the potential of a curing accelerator can be improved by such an interaction.

In this embodiment, the upper limit of the pKa of the lactone compound may be, for example, 6 or less, 5.5 or less, 5 or less, or 4.6 or less. Thereby, the potential of an epoxy resin composition can be improved. The lower limit of the pKa of the lactone compound is not particularly limited, and may be 2 or more, for example.

Among them, it is known that the pKa of the aromatic hydroxyl group is about 9 to 10. For example, the pKa of a 6-membered cyclic lactone having a hydroxyl group bonded to an aromatic ring as shown in the following formula is 9.5. As a result of studies conducted by the present inventors, it is known that it is difficult to obtain a potential effect like this embodiment in this lactone compound.

In contrast, the lactone compound according to this embodiment is one which does not have a hydroxyl group bonded to an aromatic ring and has a hydroxyl group bonded to a lactone ring. On the other hand, in the case of a compound having a highly reactive hydroxyl group bonded to an aromatic compound, the reaction between the hydroxyl group and the epoxy resin reduces the interaction with the curing accelerator, and a potential effect cannot be obtained.

The components of the epoxy resin composition according to this embodiment will be described in detail.

[Epoxy resin (A)]

As the epoxy resin (A) of this embodiment, all monomers, oligomers, and polymers having two or more epoxy groups in one molecule can be used, and the molecular weight and molecular structure are not particularly limited. In this embodiment, it is particularly preferable to use a non-halogenated epoxy resin as the epoxy resin (A).

核的環氧樹脂；二環戊二烯改質酚型環氧樹脂等橋接環狀烴基化合物改質酚型環氧樹脂等。可以單獨使用它們， 亦可以組合兩種以上而使用。 Examples of the epoxy resin (A) include biphenyl epoxy resins, bisphenol epoxy resins such as bisphenol A epoxy resin, bisphenol F epoxy resin, and tetramethylbisphenol F epoxy resin. Epoxy resin; styrenic epoxy resin; novolac epoxy resin such as phenol novolac epoxy resin, cresol novolac epoxy resin; triphenylmethane epoxy resin, alkyl modified three Polyfunctional epoxy resins such as phenylmethane type epoxy resins; aralkylphenol type epoxy resins having a phenylene skeleton, aralkylphenol type epoxy resins having an phenylene skeleton Basic epoxy resins; dihydroxynaphthalene epoxy resins, naphthol epoxy resins such as epoxy resins obtained by dipropylation of dihydroxynaphthalene dimers; triglycidyl trimerization Isocyanate, monoallyl diglycidyl triisocyanate, etc.

Core epoxy resin; dicyclopentadiene modified phenol type epoxy resin, etc. bridged cyclic hydrocarbon compounds modified phenol type epoxy resin, etc. They can be used alone or in combination of two or more.

Among these, bisphenol-type epoxy resin, biphenyl-type epoxy resin, novolak-type epoxy resin, and aralkylphenol-type epoxy resin can be used from a viewpoint of improving the balance of moisture resistance reliability and moldability. At least one of a resin and a triphenylmethane type epoxy resin. From the viewpoint of suppressing warpage of the semiconductor device, at least one of an aralkylphenol-type epoxy resin and a novolak-type epoxy resin can be used. In order to improve fluidity, a biphenyl type epoxy resin can be used. In order to control the elastic modulus at a high temperature, a biphenylaralkyl type epoxy resin can be used. Among them, a triphenylmethane type epoxy resin or a biphenylaralkyl type epoxy resin can be used.

The triphenylmethane type epoxy resin contains a structural unit represented by the following general formula (4) and / or the following general formula (5).

(In the general formulae (4) and (5), R ₁₀ , R _11, and R ₁₂ are each a hydrocarbon group having 1 to 6 carbon atoms or an aromatic hydrocarbon group having 6 to 14 carbon atoms, and may be the same or different from each other. A and c Is an integer from 0 to 3, and b is an integer from 0 to 4, which may be the same as or different from each other. X ₁ represents a single bond or is represented by any one of the following general formulae (5A), (5B), or (5C) In the following general formulae (5A), (5B), and (5C), R ₁₃ , R ₁₄ , R _15, and R ₁₆ are each a hydrocarbon group having 1 to 6 carbon atoms or an aromatic hydrocarbon group having 6 to 14 carbon atoms. It can be the same or different. D is an integer from 0 to 2, and e, f, and g are integers from 0 to 4, which may be the same or different from each other.)

The biphenylaralkyl-type epoxy resin contains a structural unit represented by the following general formula (6).

(X ₂ represents a hydrogen atom or a group represented by the following general formula (6B).)

The lower limit of the content of the epoxy resin (A) in the present embodiment is preferably 1% by weight or more, more preferably 3% by weight or more, and 5% by weight or more with respect to 100% by weight of the entire epoxy resin composition. Better. The upper limit of the content of the epoxy resin (A) is preferably 90% by weight or less, more preferably 80% by weight or less, and more preferably 70% by weight or less with respect to 100% by weight of the entire epoxy resin composition. . By setting the content of the epoxy resin (A) to the above preferable range, low hygroscopicity can be improved. In addition, by setting the content of the epoxy resin (A) to the above preferable range, solder crack resistance of the obtained semiconductor device can be improved. In this embodiment, the improvement in solder crack resistance refers to a characteristic that, even when the obtained semiconductor device has been exposed to a high temperature during a solder immersion or solder reflow process, cracks or peeling defects are hard to occur.

In this embodiment, the content relative to the entire epoxy resin composition refers to the content relative to the entire solid content except the solvent in the epoxy resin composition when the epoxy resin composition contains a solvent.

In addition, it is a biphenylaralkyl-type epoxy resin with respect to the entire epoxy resin (A). The lower limit of the content of the epoxy resin (A) of the resin or triphenylmethane type epoxy resin is, for example, preferably 85% by weight or more, more preferably 90% by weight or more, and more preferably 95% by weight or more. This can improve fluidity. On the other hand, the upper limit of the content of the epoxy resin (A) as a biphenylaralkyl-type epoxy resin or a triphenylmethane-type epoxy resin with respect to the entire epoxy resin (A) is not particularly limited, However, it may be, for example, 100% by weight or less, 99% by weight or less, and 98% by weight or less.

[Phenol resin (B)]

The phenol resin (B) of this embodiment is all monomers, oligomers, and polymers having two or more phenolic hydroxyl groups in one molecule, and the molecular weight and molecular structure are not particularly limited.

Examples of the phenol resin (B) include phenols typified by phenol novolac resin and cresol novolac resin under acidic catalysts, cresol, resorcinol, catechol, bisphenol A, Novolac resin obtained by condensation or co-condensation of phenols such as bisphenol F, phenylphenol, aminephenol, α-naphthol, β-naphthol, and dihydroxynaphthalene; and formaldehyde or ketone; Phenyl aralkyl resins having a phenylene skeleton and phenol aralkyl resins having a phenylene skeleton, synthesized from methoxy-p-xylene or bis (methoxymethyl) biphenyl Phenol resin, triphenylmethane type phenol resin having a triphenol methane skeleton, and the like. They can be used alone or in combination of two or more. Among them, a triphenylmethane type phenol resin or a biphenylaralkyl type phenol resin can be used.

The triphenylmethane-type phenol resin contains a structural unit represented by the following general formula (7) and / or the following general formula (8).

(In the general formulae (7) and (8), R ₁₇ , R _18, and R ₁₉ are each a hydrocarbon group having 1 to 6 carbon atoms or an aromatic hydrocarbon group having 6 to 14 carbon atoms. They may be the same as or different from each other. Y ₃ represents Hydroxy. H and j are integers of 0 to 3, and i is an integer of 0 to 4, which may be the same or different from each other. Y ₁ represents a single bond or is represented by the following general formula (8A), (8B), or (8C) R ₂₀ , R ₂₁ , R ₂₂ and R ₂₃ in the general formulae (8A) to (8C) are each a hydrocarbon group having 1 to 6 carbon atoms or an aromatic hydrocarbon group having 6 to 14 carbon atoms. The same or different. K is an integer from 0 to 2, and l, m, and n are integers from 0 to 4, which may be the same or different from each other.)

The biphenylaralkyl-type phenol resin contains a structural unit represented by the following general formula (9).

(Y ₂ represents a hydrogen atom or a group represented by the following general formula (9B).)

The lower limit of the content of the phenol resin (B) in the present embodiment is, for example, 1% by weight or more, more preferably 2% by weight or more, and 3% by weight or more based on 100% by weight of the entire epoxy resin composition. good. In addition, the upper limit of the content of the phenol resin (B) is preferably 60% by weight or less, more preferably 50% by weight or less, and more preferably 40% by weight or less with respect to 100% by weight of the entire epoxy resin composition. By setting the content of the phenol resin (B) to the above preferable range, it is possible to improve low hygroscopicity or fluidity. In addition, by setting the content of the phenol resin (B) to the above-mentioned more preferable range, solder crack resistance of the obtained semiconductor device can be improved.

In addition, the lower limit value of the content of the phenol resin (B) as a biphenylaralkyl-type phenol resin or a triphenylmethane-type phenol resin is preferably 95% by weight or more with respect to the entire phenol resin (B). More preferably, it is more than 97% by weight, and more preferably more than 97% by weight. This can improve fluidity. On the other hand, the upper limit value of the content of the phenol resin (B) as a biphenylaralkyl-type phenol resin or a triphenylmethane-type phenol resin with respect to the entire phenol resin (B) is not particularly limited, and for example, it may be It may be 100% by weight or less, may be 99% by weight or less, and may be 98% by weight or less.

[Curing accelerator (C)]

The curing accelerator (C) of the present embodiment may be any one that can accelerate the crosslinking reaction between the epoxy resin (A) and the phenol resin (B), and can be used by a user in a general resin composition for semiconductor sealing. The said hardening accelerator (C) can contain a cationic hardening accelerator, for example.

The curing accelerator (C) of the present embodiment may contain one or two or more kinds selected from, for example, organic phosphines, tetra-substituted phosphonium compounds, phosphate betaine compounds, adducts of phosphine compounds and quinone compounds, phosphonium compounds and Compounds containing phosphorus atoms, such as adducts of silane compounds; exemplified by 1,8-diazinebicyclo (5,4,0) undecene-7, benzyldimethylamine, 2-methylimidazole, etc. Or a tertiary amine, a nitrogen atom-containing compound such as the aforementioned tertiary amine or quaternary salt of an amine. Among these, a compound containing a phosphorus atom is preferable from the viewpoint of improving the curability. In addition, from the viewpoint of improving the balance between moldability and curability, those containing a tetra-substituted fluorene compound, a phosphate betaine compound, an addition product of a phosphine compound and a quinone compound, an addition product of a fluorene compound and a silane compound, and the like have Latent is better.

Examples of the organic phosphine that can be used in the epoxy resin composition of this embodiment include, for example, first phosphine such as ethylphosphine and phenylphosphine; second phosphine such as dimethylphosphine and diphenylphosphine; trimethyl Third phosphine such as phosphine, triethylphosphine, tributylphosphine, triphenylphosphine.

Examples of the tetra-substituted fluorene compound that can be used in the epoxy resin composition of this embodiment include a compound represented by the following general formula (10).

(In the general formula (10), P represents a phosphorus atom. R ⁴ , R ⁵ , R ^6, and R ⁷ represent an aromatic group or an alkyl group. A represents an aromatic ring having at least one member selected from a hydroxyl group, a carboxyl group, and a sulfur group. An anion of an aromatic organic acid of any of the functional groups of an alcohol group. AH represents an aromatic organic acid having at least one functional group selected from a hydroxyl group, a carboxyl group, and a thiol group on an aromatic ring. X , Y is a number from 1 to 3, z is a number from 0 to 3, and x = y.)

The compound represented by general formula (10) is obtained as follows, for example, but it is not limited to this. First, a tetra-substituted phosphonium halide, an aromatic organic acid, and a base are mixed in an organic solvent and uniformly mixed to generate an aromatic organic acid anion in the solution system. Next, when water is added, the compound represented by general formula (10) can be precipitated. Among the compounds represented by the general formula (10), R ⁴ , R ⁵ , R ^6, and R ⁷ bonded to a phosphorus atom are phenyl groups, and AH is a compound having a hydroxyl group on an aromatic ring, that is, phenols, and A is preferably the anion of the phenol. Examples of the phenols include monocyclic phenols such as phenol, cresol, resorcinol, and catechol, condensed polycyclic phenols such as naphthol, dihydroxynaphthalene, and anthraquinol, and bisphenol A. , Bisphenols such as bisphenol F and bisphenol S, polycyclic phenols such as phenylphenol and biphenol.

Examples of the phosphate betaine compound that can be used in the epoxy resin composition of the present embodiment include a compound represented by the following general formula (11).

(In the general formula (11), P represents a phosphorus atom. R ⁸ represents an alkyl group having 1 to 3 carbon atoms, R ⁹ represents a hydroxyl group. F is a number of 0 to 5, and g is a number of 0 to 3.)

The compound represented by the general formula (11) is obtained, for example, as follows. First, the third aromatic substituted phosphine, which is the third phosphine, is contacted with a diazonium salt, and is obtained through a process of substituting the diaromatic group of the triaromatic substituted phosphine and the diazonium salt. However, it is not limited to this.

Examples of the adduct of a phosphine compound and a quinone compound that can be used in the epoxy resin composition of the present embodiment include a compound represented by the following general formula (12).

(In the general formula (12), P represents a phosphorus atom. R ¹⁰ , R ^11, and R ¹² represent an alkyl group having 1 to 12 carbon atoms or an aryl group having 6 to 12 carbon atoms, and may be the same or different from each other. R ¹³ , R ¹⁴ and R ¹⁵ represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, which may be the same as or different from each other, or R ¹⁴ and R ^{15 may} be bonded to form a cyclic structure.)

Phosphine compounds used as an adduct of a phosphine compound and a quinone compound are, for example, triphenylphosphine, tri (alkylphenyl) phosphine, tri (alkoxyphenyl) phosphine, trinaphthylphosphine, tris (benzyl) A group such as phosphine is preferably unsubstituted on the aromatic ring or has a substituent such as an alkyl group or an alkoxy group, and examples of the substituent such as an alkyl group or an alkoxy group include those having 1 to 6 carbon atoms. From the viewpoint of obtaining simplicity, triphenylphosphine is preferred.

Further, examples of the quinone compound used in the adduct of a phosphine compound and a quinone compound include benzoquinone and anthraquinones. Among them, p-benzoquinone is preferable from the viewpoint of storage stability.

As a method for producing an adduct of a phosphine compound and a quinone compound, an adduct can be obtained by contacting and mixing both an organic third phosphine and a benzoquinone in a solvent that can be dissolved. The solvent is a ketone such as acetone or methyl ethyl ketone, and any solvent may be used as long as it has low solubility in the adduct. However, it is not limited to this.

As a compound represented by the general formula (12), R ¹⁰ , R ^11, and R ¹² bonded to a phosphorus atom are phenyl groups from the viewpoint of reducing the thermal modulus of elasticity of a cured product of the resin composition for sealing, and Compounds in which R ¹³ , R ¹⁴ and R ¹⁵ are hydrogen atoms, and even compounds in which 1,4-benzoquinone and triphenylphosphine are added are preferred.

Examples of the adduct of a fluorene compound and a silane compound that can be used in the epoxy resin composition of the present embodiment include, for example, a compound represented by the following general formula (13).

(In the general formula (13), P represents a phosphorus atom, and Si represents a silicon atom. R ¹⁶ , R ¹⁷ , R ^18, and R ¹⁹ each represent an organic group having an aromatic ring or a heterocyclic ring, or an aliphatic group, and may be the same as each other. It may be different. In the formula, R ²⁰ is an organic group bonded to Y ² and Y ^{3. In the} formula, R ²¹ is an organic group bonded to Y ⁴ and Y ^5. Y ² and Y ³ represent a proton donating group Y ² and Y ^{3 in the} same molecule are bonded to the silicon atom to form a chelate structure. Y ⁴ and Y ⁵ represent the bases that proton donated by the proton donating group. Y ⁴ and Y ⁵ are bonded to a silicon atom to form a chelate structure. R ²⁰ and R ²¹ may be the same as or different from each other, and Y ² , Y ³ , Y ^4, and Y ⁵ may be the same or different from each other. Z ¹ It is an organic group having an aromatic ring or a heterocyclic ring, or an aliphatic group.)

In the general formula (13), examples of R ¹⁶ , R ¹⁷ , R ¹⁸ and R ¹⁹ include phenyl, methylphenyl, methoxyphenyl, hydroxyphenyl, naphthyl, hydroxynaphthyl, and benzyl , Methyl, ethyl, n-butyl, n-octyl, and cyclohexyl, etc. Among these, alkyl, alkane such as phenyl, methylphenyl, methoxyphenyl, hydroxyphenyl, and hydroxynaphthyl An aromatic group or an unsubstituted aromatic group having a substituent such as an oxy group or a hydroxyl group is more preferred.

In the general formula (13), R ²⁰ is an organic group bonded to Y ² and Y ³ . Similarly, R ²¹ is an organic group bonded to Y ⁴ and Y ⁵ . Y ² and Y ³ are bases formed by proton-donating groups, and Y ² and Y ^{3 in the} same molecule are bonded to a silicon atom to form a chelate structure. Similarly, Y ⁴ and Y ⁵ are bases formed by proton-donating groups, and Y ⁴ and Y ^{5 in the} same molecule are bonded to a silicon atom to form a chelate structure. R ²⁰ and R ²¹ may be the same as or different from each other, and Y ² , Y ³ , Y ^4, and Y ⁵ may be the same or different from each other. The base represented by -Y ² -R ²⁰ -Y ³ -and Y ⁴ -R ²¹ -Y ⁵ -in this general formula (13) is a base constituted by a proton donor emitting two protons, as The proton donor is preferably an organic acid having at least two carboxyl groups or hydroxyl groups in the molecule, and more preferably an aromatic compound having at least two carboxyl groups or hydroxyl groups on adjacent carbons constituting the aromatic ring. Aromatic compounds having at least two hydroxyl groups on adjacent carbons are more preferred, such as catechol, gallophenol, 1,2-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,2'-biphenol, 1 , 1'-bis-2-naphthol, salicylic acid, 1-hydroxy-2-naphthoic acid, 3-hydroxy-2-naphthoic acid, chloranic acid, tannic acid, 2-hydroxybenzyl alcohol, 1, 2-Cyclohexanediol, 1,2-propanediol, glycerol, etc. Among these, catechol, 1,2-dihydroxynaphthalene, and 2,3-dihydroxynaphthalene are more preferable.

In addition, Z ¹ in the general formula (13) represents an organic group or an aliphatic group having an aromatic ring or a hetero ring, and specific examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, and an octyl group. Aliphatic hydrocarbon groups, aromatic hydrocarbon groups such as phenyl, benzyl, naphthyl, and biphenyl groups, glycidyloxy propyl, mercaptopropyl, aminopropyl, and other glycidyloxy, mercapto groups And reactive substituents such as alkyl groups and vinyl groups having an amine group, but among these, methyl, ethyl, phenyl, naphthyl, and biphenyl groups are more preferable from the viewpoint of thermal stability.

As a method for producing an adduct of a europium compound and a silane compound, a silane compound such as phenyltrimethoxysilane and a proton donor such as 2,3-dihydroxynaphthalene are added to a flask containing methanol and dissolved, and then A sodium methoxide-methanol solution was added dropwise with stirring at room temperature. In addition, when a solution prepared by dissolving a tetra-substituted phosphonium halide such as tetraphenylphosphonium bromide in methanol prepared in advance was dropped into the flask with stirring at room temperature, crystals were precipitated. When the precipitated crystal was filtered, washed with water, and dried under vacuum, an adduct of a sulfonium compound and a silane compound was obtained. However, the manufacturing method of an adduct of a fluorene compound and a silane compound is not limited to this.

The lower limit of the content of the curing accelerator (C) in the present embodiment is, for example, 0.05% by weight or more, more preferably 0.08% by weight or more, and 0.1% by weight or more with respect to 100% by weight of the entire epoxy resin composition. Better. In addition, the upper limit value of the content of the curing accelerator (C) with respect to 100% by weight of the entire epoxy resin composition is, for example, preferably 10% by weight or less, more preferably 7.5% by weight or less, and even more preferably 5% by weight or less. . By making content of the said hardening accelerator (C) more than the said lower limit, appropriate hardening can be performed. And, by fixing the above The content of the chemical accelerator (C) is set to be equal to or less than the above-mentioned upper limit value, and it is possible to improve storability or fluidity.

[Lactone compound]

The lactone compound according to this embodiment includes a lactone compound having the following structural unit (1) in which the lactone ring A has at least one hydroxyl group.

(In the above structural unit (1), m represents an integer of 1 or 2, and n represents an integer of 1 to 6. B represents a monovalent or divalent organic group. Ra independently represents a hydrogen atom, a hydroxyl group, and an alkyl group. N When it is 2 or more, Ra may be bonded to each other to form a ring. Ra may be unsubstituted or may have a substituent.)

The lactone ring A may have, for example, a heterocyclic compound having a 5- to 7-membered ring, and a heterocyclic compound having a 6-membered ring is more preferred. In this case, the hetero atom of the heterocyclic compound is an oxygen atom.

In the lactone ring A of the 6-membered ring, a benzene skeleton, a naphthalene skeleton, or a pyridine skeleton can be condensed on the lactone ring A (lactone skeleton) of the 6-membered ring by condensation of adjacent carbon atoms.

The lactone compound of this embodiment may have a coumarin structure or a biscoumarin structure.

The lactone compound having a coumarin structure can contain a structure represented by the following general formula (I).

R ₁ to R ₈ in the general formula (I) may be the same or different. R ₁ to R ₈ represent a hydrogen atom, a hydroxyl group, and a carbon number of 1 to 20 (1 to 12 are preferred, and 1 to 6 are more preferred). The alkyl group has a linear or branched alkyl group, or an aromatic group having 6 to 20 carbon atoms. Radical, alkaryl or aralkyl. Among them, at least one of R ₁ to R ₄ is a hydroxyl group. In this embodiment, R ₄ in the general formula (I) may have a hydroxyl group.

The lactone compound having a biscoumarin structure is not particularly limited, but may be a structure in which two of the coumarin structures are linked by a predetermined cross-linking group (via B in the structural formula (1)).

The lactone compound having such a biscoumarin structure can contain a structure represented by the following general formula (II).

(II)

(II)

R in the general formula (II) is selected from the following chemical formulas.

In this embodiment, a lactone compound having a coumarin structure can increase the potential effect of the epoxy resin composition compared to a lactone compound having a coumarin structure. The detailed mechanism is not clear, but it is considered as follows. That is, the biscoumarin skeleton having two coumarin skeletons bonded thereto has a structure in which physical flow is restricted. Therefore, the coordination bond between the anion and the cation can be more stabilized. In this case, it is considered that the coordination bond or ionic bond (interaction) of the cation to the biscoumarin skeleton with respect to the curing accelerator can be made stronger, and the cation can be further stabilized. Therefore, by using a lactone compound having a coumarin structure, even if a small amount of the lactone compound having a coumarin structure is added, an effect equivalent to or more than that can be obtained.

In this embodiment, the lower limit of the molar ratio of the lactone compound content to the curing accelerator (C) content in the epoxy resin composition may be, for example, 0.1 or more, preferably 0.2 or more, and more preferably 0.3 or more. Therefore, the potentiality or fluidity of the epoxy resin composition can be improved. It is possible to further improve the storability of the epoxy resin composition. In addition, the upper limit of the molar ratio of the lactone compound content to the curing accelerator (C) content in the epoxy resin composition is not particularly limited, but may be, for example, 4 or less, preferably 3 or less, and more preferably 2 or less. good. Accordingly, it is possible to improve the balance between the potential of the epoxy resin composition and the curing characteristics.

In this embodiment, the lower limit of the content of the lactone compound may be, for example, 0.01% by weight or more, more preferably 0.02% by weight or more, and more preferably 0.025% by weight or more with respect to the entire epoxy resin composition. Therefore, the potentiality or fluidity of the epoxy resin composition can be improved. It is possible to further improve the storability of the epoxy resin composition. In addition, the upper limit value of the content of the lactone compound with respect to the entire epoxy resin composition is not particularly limited, but may be, for example, 1% by weight or less, more preferably 0.75% by weight or less, and even more preferably 0.5% by weight or less. Therefore, the epoxy resin group can be improved The potential of the product is balanced with the curing characteristics.

[Inorganic Filler (D)]

The epoxy resin composition of this embodiment can further contain an inorganic filler (D).

In this embodiment, the inorganic filler (D) is not particularly limited, but examples thereof include melt-pulverized silica, fused silica, crystalline silica, secondary agglomerated silica, alumina, titania, and hydrogen. Alumina, talc, clay, fiberglass, etc. One of these can be used or a combination of two or more can be used. Among these, fused silica is particularly preferable as the inorganic filler (D). Since the fused silica has a low reactivity with the curing accelerator (C), even when a large amount is blended into the epoxy resin composition of this embodiment, the curing reaction of the epoxy resin composition can be prevented from being hindered. Furthermore, by using fused silicon dioxide as the inorganic filler (D), the reinforcing effect of the obtained semiconductor device is further enhanced.

The shape of the inorganic filler (D) may be, for example, any of granular, lumpy, and scaly shapes. Among them, granular (particularly spherical) is preferred.

The lower limit of the average particle diameter of the inorganic filler (D) according to this embodiment is, for example, preferably 1 μm or more, and more preferably 3 μm or more. The upper limit value of the average particle diameter of the inorganic filler (D) is, for example, preferably 100 μm or less, and more preferably 50 μm or less. By making the average particle diameter of the said inorganic filler (D) into the said range, filling property can be improved and the increase of the melt viscosity of an epoxy resin composition can be suppressed.

The lower limit of the content of the inorganic filler (D) in the present embodiment is, for example, 40% by weight or more, more preferably 50% by weight or more, and 60% by weight or more relative to 100% by weight of the entire epoxy resin composition. good. In addition, the upper limit value of the content of the inorganic filler (D) relative to 100% by weight of the entire epoxy resin composition is preferably 97.5% by weight or less, and 97% by weight. The amount is more preferably at most%, and more preferably at most 95% by weight. By setting the content of the inorganic filler (D) to the above lower limit value or more, it is possible to suppress warpage of the package molded using the epoxy resin composition of the present embodiment, and to suppress moisture absorption or decrease strength. decline. In addition, by setting the content of the inorganic filler (D) to be equal to or less than the above-mentioned upper limit value, the fluidity of the epoxy resin composition of the present embodiment can be improved, and the moldability is good.

The epoxy resin composition according to this embodiment may contain other additives in addition to the compounds (A) to (D) and the lactone compound as necessary. As other additives, for example, coupling agents such as γ-glycidoxypropyltrimethoxysilane, colorants such as carbon black, flame retardants such as brominated epoxy resins, antimony oxide, and phosphorus compounds, silicone oil, Low-stress components such as silicone rubber, natural waxes, synthetic waxes, higher fatty acids, release agents such as metal salts, paraffin wax, and various additives such as antioxidants. One or two or more of these compounds can be used.

The method for producing an epoxy resin composition according to this embodiment is obtained, for example, by the following steps: in addition to the compounds (A) to (D) and the lactone compound described above, other additives are mixed at room temperature using a mixer if necessary. , And heating and kneading using a hot roll, a heating kneader, and the like for cooling and pulverization.

The epoxy resin composition according to this embodiment can be used as a sealing resin composition used for sealing electronic components such as semiconductor elements.

The semiconductor device of this embodiment can include a semiconductor element and a sealing member that seals the semiconductor element. This type of sealing member is made of a cured product of the epoxy resin composition of the present embodiment. The semiconductor device according to this embodiment is obtained by curing the above-mentioned epoxy resin composition using a molding method such as a transfer mold, a compression mold, and an injection mold, and sealing an electronic component such as a semiconductor element.

The semiconductor device according to this embodiment is not particularly limited, and examples thereof include SIP (Single Inline Package), HSIP (SIP with Heatsink), and ZIP (Zig-zag Inline Package) Package), DIP (Dual Inline Package), SDIP (Shrink Dual Inline Package), SOP (Small Outline Package), SSOP (Shrink Small Outline Package), TSOP (Thin Small Outline Package), SOJ (Small Outline J-leaded Package), QFP (Quad Flat Package), QFP (FP) (QFP Fine Pitch, Fine Pitch Quad Flat Package), TQFP (Thin Quad Flat Package), QFJ (PLCC) (Quad Flat J-leaded Package), BGA (Ball Grid Array) .

Next, a semiconductor device 100 will be described using FIG. 1.

FIG. 1 is a cross-sectional view showing an example of a semiconductor device 100.

The semiconductor device 100 is a semiconductor package including a substrate 10, a semiconductor element 20 mounted on one surface of the substrate 10, the aforementioned one surface of the sealing substrate 10, and a sealing resin layer 30 of the semiconductor element 20. That is, in the semiconductor device 100, the other side of the substrate 10 opposite to the one side described above is not a single-sided sealed semiconductor package that is not sealed by the sealing resin layer 30. The sealing resin layer 30 is formed of a cured product of the epoxy resin composition according to this embodiment. Accordingly, the linear expansion coefficient of the sealing resin layer 30 in the hot state can be increased, and therefore, the difference between the thermal expansion coefficients of the sealing resin layer 30 and the substrate 10 in the hot state can be reduced. For this reason, when used in a high-temperature environment, it is possible to suppress warping of the entire semiconductor device 100.

In this embodiment, the upper surface of the semiconductor element 20 may be covered with the sealing resin layer 30 (FIG. 1), or may be exposed from the sealing resin layer 30 (not shown).

In the example shown in FIG. 1, the substrate 10 is an organic substrate. A plurality of solder balls 12 are provided on the back surface of the substrate 10 opposite to the surface (mounting surface) on which the semiconductor element 20 is mounted, for example. The semiconductor element 20 is flip-chip mounted on, for example, the substrate 10. The semiconductor element 20 is electrically connected to the substrate 10 via, for example, a plurality of bumps 22. As a modification, the semiconductor element 20 may be electrically connected to the substrate 10 via a bonding wire.

In the example shown in FIG. 1, the gap between the semiconductor element 20 and the substrate 10 is filled with, for example, a primer 32. As the primer 32, for example, a film-like or liquid primer material can be used. The primer 32 and the sealing resin layer 30 may be composed of different materials, or may be composed of the same material. The epoxy resin composition of this embodiment can be used as a mold base material. Therefore, it is also possible that the primer 32 and the sealing resin layer 30 are made of the same material and formed by the same process. Specifically, the sealing process of sealing the semiconductor element 20 with the epoxy resin composition and the filling process of filling the gap between the substrate 10 and the semiconductor element 20 with the epoxy resin composition can be performed in the same process (unified).

In this embodiment, the thickness of the sealing resin layer 30 can be set as the shortest distance from the mounting surface of the substrate 10 (the surface opposite to the surface on which the solder balls 12 for external connection are formed) to the top surface of the sealing resin layer 30. In addition, the thickness of the sealing resin layer 30 refers to the thickness of the sealing resin layer 30 in the normal direction of one surface of the substrate 10 on which the semiconductor element 20 is mounted with the one surface as a reference. In this case, the upper limit value of the thickness of the sealing resin layer 30 may be, for example, 0.4 mm or less, may be 0.3 mm or less, and may be 0.2 mm or less. On the other hand, the lower limit value of the thickness of the sealing resin layer 30 is not particularly limited, and may be, for example, 0 mm or more (exposed type) or 0.01 mm or more.

The upper limit value of the thickness of the substrate 10 may be set to, for example, 0.8 mm or less, or may be set to 0.4mm or less. On the other hand, the lower limit value of the thickness of the substrate 10 is not particularly limited, and may be, for example, 0.1 mm or more.

According to this embodiment, it is possible to reduce the thickness of the semiconductor package in this manner. In addition, even if it is a thin semiconductor package, the sealing resin layer 30 is formed by using the epoxy resin composition according to this embodiment, so that warping of the semiconductor device 100 can be suppressed. In addition, in the present embodiment, the thickness of the sealing resin layer 30 can be set to the thickness of the substrate 10 or less, for example. Therefore, the semiconductor device 100 can be made thinner more effectively.

Next, the structure 102 will be described.

FIG. 2 is a cross-sectional view showing an example of the structure body 102. The structure 102 is a molded product formed by MAP molding. Therefore, by slicing the structure 102 on each semiconductor element 20, a plurality of semiconductor packages can be obtained.

The structure 102 includes a substrate 10, a plurality of semiconductor elements 20, and a sealing resin layer 30. The plurality of semiconductor elements 20 are arranged on one surface of the substrate 10. FIG. 2 illustrates a case where each semiconductor element 20 is flip-chip mounted on the substrate 10. At this time, each semiconductor element 20 is electrically connected to the substrate 10 via a plurality of bumps 22. On the other hand, each semiconductor element 20 may be electrically connected to the substrate 10 via a bonding wire. The substrate 10 and the semiconductor element 20 can be the same as those exemplified in the semiconductor device 100.

In the example shown in FIG. 2, the gap between each semiconductor element 20 and the substrate 10 is filled with, for example, a primer 32. As the primer 32, for example, a film-like or liquid primer material can be used. On the other hand, the aforementioned epoxy resin composition can be used as a mold primer material. At this time, the sealing of the semiconductor element 20 and the filling of the gap between the substrate 10 and the semiconductor element 20 are performed in unison.

The sealing resin layer 30 seals the above-mentioned one of the plurality of semiconductor elements 20 and the substrate 10. At this time, the other side of the substrate 10 that is opposite to the one side is not sealed by the sealing resin layer 30. The sealing resin layer 30 is formed of a cured product of the epoxy resin composition described above. Accordingly, it is possible to suppress warpage of the structure body 102 or a semiconductor package obtained by slicing the structure body 102. The sealing resin layer 30 is formed by sealing molding, for example, an epoxy resin composition using a known method such as a transfer molding method or a compression molding method. In addition, in this embodiment, as shown in FIG. 2, the upper surface of each semiconductor element 20 may be sealed by the sealing resin layer 30 or may be exposed from the sealing resin layer 30.

In this embodiment, the case where the epoxy resin composition of this invention is used as a sealing material of a semiconductor device was demonstrated, but the use as an epoxy resin composition of this invention is not limited to this. And, for example, the epoxy resin composition of this invention can be used for the package which requires wire bonding.

As mentioned above, although embodiment of this invention was described referring an accompanying drawing, these are the illustration of this invention, Various structures other than the above can be employ | adopted.

[Example]

Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to the description of any of these examples.

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

(Preparation of epoxy resin composition)

First, in Examples 1 to 13 and Comparative Example 1, each raw material blended in accordance with Table 1 was mixed with a mortar at normal temperature, and then melt-mixed on a hot plate at 120 ° C for 3 minutes. After cooling, it was pulverized at room temperature again using a mortar to obtain an epoxy resin composition.

In addition, in Example 14, Example 15, and Comparative Example 2, each raw material blended according to Table 2 was mixed at room temperature using a mixer, and then roll-kneaded at 70 to 100 ° C. After cooling, it was pulverized to obtain an epoxy resin composition.

The details of each component in Tables 1 and 2 are as follows. The units in Tables 1 and 2 are% by weight.

Epoxy resin (A)

Epoxy resin 1: aralkylphenol type epoxy resin having a biphenyl group (NC-3000 manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent 276 g / eq, softening point 57 ° C)

Phenol resin (B)

Phenol resin 1: Aralkyl phenol resin with a biphenyl group (GPH-65 manufactured by Nippon Kayaku Co., Ltd., hydroxyl equivalent 196g / eq, softening point 65 ° C)

Curing accelerator (C)

Cure accelerator 1: Compound obtained by adding 1,4-benzoquinone and triphenylphosphine obtained by the following synthesis method

[Synthesis method of curing accelerator 1]

A separable flask with a cooling tube and a stirring device was charged with 6.49 g (0.060 mol) of benzoquinone, 17.3 g (0.066 mol) of triphenylphosphine and 40 ml of acetone, and the reaction was performed at room temperature with stirring. The precipitated crystals were washed with acetone, and then filtered and dried to obtain a curing accelerator 1 for dark green crystals.

Lactone compound

Lactone compound 1: Dicoumarin represented by the following formula (manufactured by Tokyo Chemical Industry Co., Ltd., M0216)

Lactone compound 2: 4-hydroxycoumarin represented by the following formula (manufactured by Tokyo Chemical Industry Co., Ltd., H0235)

Inorganic filler (D)

Inorganic filling material 1: Fused spherical silica (average particle size: 31 μm, specific surface area: 1.6 m ² / g, manufactured by Denka Corporation, FB-508S)

(additive)

Silane coupling agent 1: 3-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-403)

Colorant 1: Carbon black (manufactured by Mitsubishi Chemical Corporation, MA600)

Release agent 1: glycerol montanate (melting point 80 ° C, manufactured by Clariant International Ltd, Licolub WE4)

Ion scavenger 1: Hydrotalcite (DHT-4H, manufactured by Kyowa Chemical Industry Co., Ltd.)

Low stress reducing agent 1: epoxy polyether modified siloxane (manufactured by Toray Dow Corning Co., Ltd., FZ-3730)

Low stress reducing agent 2: carboxy-terminated butadiene acrylonitrile copolymer (manufactured by PTI Japan Limited, CTBN1008-SP)

Each evaluation of the epoxy resin composition was performed for each Example and each comparative example as follows.

(Vulcanization test @ 175 ℃)

Using a vulcanization tester (A & D Company, Limited, vulcanization tester WP type), the vulcanization test torque of the epoxy resin composition was measured at a mold temperature of 175 ° C over time, and the vulcanization test torque was measured 4 minutes after the measurement was started. The value is set to the saturation torque value. In addition, for a flat plate, 4.3 g of an epoxy resin composition was added to a mold of 25 mm φ, and tableting was performed for 5 t and 1 minute. In the epoxy resin composition, a test was performed on a sample immediately after the flat plate was produced and a sample stored in a constant temperature bath at 40 ° C. for 24 hours and 72 hours. In addition, the time when the vulcanization test was started was observed from the time when about 60% of the reactive functional groups had reacted.

(DSC)

Using a differential scanning calorimeter (DSC-6100 manufactured by Seiko Instruments Inc.), under a nitrogen gas flow, under a temperature range of 10 ° C / min from 30 ° C to 300 ° C, 10 mg of the above-mentioned epoxy resin The composition was measured.

(Minimum melt viscosity)

The minimum melt viscosity was measured using (1) a viscometer or (2) a rectangular flow path pressure measurement.

(1) Viscometer: The minimum melt viscosity was measured on a flat plate epoxy resin composition using a cone-plate viscometer (manufactured by Toa Industries Co., Ltd., manufacturing number CV-1S). As the flat-plate epoxy resin composition, 100 mg of the epoxy resin composition was added to a mold of 25 mm φ, and tableting was performed for 3 t and 1 minute. In addition, in the epoxy resin composition, the sample immediately after the flat plate was prepared, the sample after being stored at 40 ° C for 24 hours, and the sample after being stored at 40 ° C for 72 hours. Tested.

The melt viscosity based on a viscometer represents the measurement result after 8 seconds from the start of measurement. The sequence is to start measurement immediately after a sample (flat-plate epoxy resin composition) is placed on a hot plate at 175 ° C. The time immediately after mounting was set to 0s, and the measured value was the value after 8s.

(2) Rectangular flow path pressure measurement: The lowest melt viscosity is measured with a low-pressure transfer molding machine (NEC Co., Ltd., 40t Manual press) at a mold temperature of 175 ° C and an injection speed of 177 cm ³ / sec. To a width of 13 mm and a length of 175 cm. The rectangular flow path is filled with the above-mentioned epoxy resin composition, and the pressure sensor is used to measure the change in pressure with time from the upstream front end of the flow path to the 25 mm embedded pressure sensor, and the minimum value when the epoxy resin composition flows is measured. pressure. In addition, about the obtained epoxy resin composition, the test was performed on the sample immediately after the flat plate was made, the sample after being stored at 40 ° C for 24 hours, and the sample after being stored at 40 ° C for 72 hours.

(Spiral flow)

In the epoxy resin compositions of Examples 14, 15 and Comparative Example 2, a low-pressure transfer molding machine (KTS-15 manufactured by Shangying Seiki Co., Ltd.) was used, at a mold temperature of 175 ° C, an injection amount of 6.9 MPa, and a holding time of 15 The epoxy resin composition obtained as described above was injected into a spiral flow measurement mold conforming to ANSI / ASTM D 3123-72 under the condition of minutes, and the flow length was measured.

(Bending strength, bending elastic modulus)

In the epoxy resin compositions of Examples 14, 15 and Comparative Example 2, JIS K 6911 was used as a standard, a transfer molding machine was used, and the mold temperature was 175 ° C, the injection pressure was 6.9 MPa, and the curing time was 15 minutes. A test piece of 4 mm (thickness) epoxy resin was molded, and flexural strength and flexural modulus were measured at 25 ° C and 260 ° C.

It can be seen from Examples 1 to 13 that the epoxy resin composition of the present invention has excellent potential different. Further, it is understood from Examples 14 and 15 that by using the epoxy resin composition of the present invention, a semiconductor sealing material having excellent potential can be obtained.

In the above, the present invention has been further specifically described based on the embodiments, but these are examples of the present invention, and various structures other than the above can be adopted.

This application claims priority based on Japanese Application Japanese Patent Application No. 2016-051944 filed on March 16, 2016 and Japanese Patent Application No. 2016-164575 filed on August 25, 2016, and the entire contents of this disclosure are incorporated herein.

10‧‧‧ substrate

12‧‧‧welding ball

20‧‧‧Semiconductor element

22‧‧‧ bump

30‧‧‧sealing resin layer

32‧‧‧ primer

100‧‧‧ semiconductor device

Claims (10)

An epoxy resin composition comprising: an epoxy resin (A); a phenol resin (B); a curing accelerator (C); and a lactone compound: the lactone ring A has at least one hydroxyl group and contains Describing the structural unit (1),

In the structural unit (1), m represents an integer of 1 or 2, n represents an integer of 1 to 6, B represents a monovalent or divalent organic group, and Ra independently represents a hydrogen atom, a hydroxyl group, or an alkyl group; When n is 2 or more, Ra may be bonded to each other to form a ring. For example, the epoxy resin composition according to item 1 of the patent application range, wherein the acid dissociation constant (pKa) of the lactone compound is 6 or less. For example, the epoxy resin composition of the first or second patent application scope, wherein the lactone ring A is a 6-membered ring. For example, the epoxy resin composition according to item 1 of the patent application scope, wherein the lactone compound has a coumarin structure or a dicoumarin structure. For example, the epoxy resin composition according to item 1 of the patent application scope, wherein the curing accelerator (C) includes a cationic curing accelerator. For example, the epoxy resin composition according to item 1 of the patent application scope, wherein the molar ratio of the lactone compound content to the curing accelerator (C) content in the epoxy resin composition is 0.1 or more and 4 or less. For example, the epoxy resin composition according to item 1 of the patent application scope, wherein the content of the lactone compound is 0.01% by weight or more and 1% by weight or less with respect to the entire epoxy resin composition. For example, the epoxy resin composition according to the first patent application scope further contains an inorganic filler. For example, the epoxy resin composition of the first patent application scope is used for sealing of semiconductor elements. A semiconductor device includes a semiconductor element and a sealing member that seals the semiconductor element, and the sealing member is made of a cured product of an epoxy resin composition according to any one of claims 1 to 9 of the scope of patent application.