Resin composition for sealing semiconductor, method for producing resin composition for sealing semiconductor, and semiconductor device

Abstract

To provide a resin composition for sealing a semiconductor that can be used to produce a sealing part for sealing a semiconductor element, that allows the sealing part to have a high glass transition point, and that can increase the long-term heat resistance of the sealing part. The resin composition for sealing contains: a maleimide compound (A); an epoxy compound (B) containing an epoxy compound (b1) having a structure represented by formula (1); a phenol compound (C) containing a phenol compound (c1) having a structure represented by formula (2); and an inorganic filler (D). In formula (1), n is a number of from 1 to 5 and m is a number of from 1 to 6. In formula (2), n is a number of from 1 to 5, R is CH3, OH, C6H5, or C6H4OH, and X is a structure represented by formula (21), a structure represented by formula (22), or a structure represented by formula (23).

Description

Semiconductor encapsulation resin composition, method for producing semiconductor encapsulation resin composition, and semiconductor device

[0001] The present disclosure generally relates to a semiconductor encapsulation resin composition, a method for producing a semiconductor encapsulation resin composition, and a semiconductor device, and more specifically to a semiconductor encapsulation resin composition containing an epoxy compound and a phenol compound, a method for producing the same, and a semiconductor device including an encapsulation part made from the semiconductor encapsulation resin composition.

[0002] When encapsulating semiconductor elements, resin encapsulation is sometimes performed for the purposes of improving productivity, reducing costs, etc. Resin encapsulation is performed by molding a semiconductor encapsulation resin composition containing, for example, an epoxy resin, a phenolic curing agent, a curing accelerator, and an inorganic filler to produce an encapsulated portion.

[0003] For example, in Patent Document 1, a semiconductor device sealed with a sealing portion includes, for example, a lead frame, a semiconductor element mounted on the lead frame, and a wire electrically connecting the semiconductor element and the lead frame, and the sealing portion seals the semiconductor element.

[0004] Patent Document 1 discloses that the encapsulating resin composition used to produce the encapsulating portion contains a bismaleimide compound, a biphenyl aralkyl phenolic resin containing a group with an unsaturated double bond, and further an epoxy resin.

[0005] Japanese Patent Application Laid-Open No. 2018-203883

[0006] An object of the present disclosure is to provide a semiconductor encapsulation resin composition that can be used to prepare an encapsulation part for encapsulating a semiconductor element, which can provide the encapsulation part with a high glass transition point and can also provide enhanced long-term heat resistance of the encapsulation part; a method for producing the semiconductor encapsulation resin composition; and a semiconductor device including an encapsulation part prepared from the semiconductor encapsulation resin composition.

[0007] A semiconductor encapsulating resin composition according to one embodiment of the present disclosure contains a maleimide compound (A), an epoxy compound (B) containing an epoxy compound (b1) having a structure represented by the following formula (1), a phenol compound (C) containing a phenol compound (c1) having a structure represented by the following formula (2), and an inorganic filler (D).

[0008]

[0009]

[0010] In formula (1), n ​​is a number from 1 to 5, and m is a number from 1 to 6.

[0011] In formula (2), n is a number of 1 to 5, R is H, CH ３ , O.H., C. ６ H ５ or C ６ H ４ OH and X are a structure represented by the following formula (21), a structure represented by the following formula (22), or a structure represented by the following formula (23).

[0012]

[0013] A method for producing a semiconductor encapsulating resin composition according to one embodiment of the present disclosure includes mixing a maleimide-epoxy kneaded mixture, which is a kneaded mixture of the maleimide compound (A) and the epoxy compound (B), with a phenol compound (C) and an inorganic filler (D).

[0014] A semiconductor device according to an aspect of the present disclosure includes a semiconductor element and an encapsulating portion encapsulating the semiconductor element, the encapsulating portion including a cured product of the semiconductor encapsulating resin composition.

[0015] FIG. 1 is a schematic cross-sectional view of a semiconductor device according to an embodiment of the present disclosure.

[0016] Hereinafter, embodiments of the present disclosure will be described. However, the present disclosure is not limited to the following embodiments. The following embodiments are merely examples of various embodiments of the present disclosure, and various modifications are possible depending on the design as long as the object of the present disclosure can be achieved. The explanation of the mechanism of action in the following embodiments is presumed, and the scope of the present disclosure is not limited to the explanation of the mechanism of action below.

[0017] The semiconductor encapsulation resin composition according to the embodiment contains a maleimide compound (A), an epoxy compound (B) containing an epoxy compound (b1) having a structure represented by the following formula (1), a phenol compound (C) containing a phenol compound (c1) having a structure represented by the following formula (2), and an inorganic filler (D).

[0018]

[0019]

[0020] In formula (1), n ​​is a number from 1 to 5, and m is a number from 1 to 6.

[0021] In formula (2), n is a number between 1 and 5, and R is H or CH ３ , X is a structure shown in the following formula (21), a structure shown in formula (22), or a structure shown in formula (23).

[0022]

[0023] According to the embodiment, the cured product of the semiconductor encapsulating resin composition and the encapsulating part including the cured product can have a high glass transition point, and the long-term heat resistance of the encapsulating part can be improved.

[0024] Because the cured product and the sealing portion can have a high glass transition point, softening of the sealing portion can be suppressed when a semiconductor device having the sealing portion is heated in a reflow furnace or the like for mounting, for example, thereby providing the sealing portion with good heat resistance. Furthermore, increasing the glass transition temperature of the cured product and the sealing portion typically tends to accelerate decomposition of the cured product and the sealing portion when the cured product and the sealing portion are continuously exposed to a high-temperature environment. This is presumably because increasing the crosslink density of the cured product and the sealing portion to increase the glass transition temperature accelerates decomposition of the cured product and the sealing portion due to dissociation of crosslinking points at high temperatures. However, in embodiments, even if the glass transition temperatures of the cured product and the sealing portion are increased, decomposition of the cured product and the sealing portion in a high-temperature environment can be suppressed. This is presumably because the semiconductor encapsulating resin composition contains the maleimide compound (A), epoxy compound (b1), and phenol compound (c1), thereby increasing the glass transition temperature of the cured product and the sealing portion without excessively increasing the crosslink density of the cured product and the sealing portion.

[0025] Since the decomposition of the cured product and the sealing portion at high temperatures is suppressed, the semiconductor device having the sealing portion can be preferably used in applications exposed to high temperatures, such as in-vehicle applications. Furthermore, the sealing portion can be preferably used, for example, in semiconductor devices, to seal heat-generating components such as power semiconductors.

[0026] The components of the semiconductor encapsulation resin composition of the embodiment (hereinafter also referred to as composition (X)) will be described in more detail.

[0027] The maleimide compound (A) is a compound having a maleimide skeleton in the molecule, and can increase the glass transition temperature of the cured product and the sealed portion.

[0028] The maleimide compound (A) preferably contains a compound having at least two maleimide skeletons in the molecule, in which case the maleimide compound (A) can further increase the glass transition temperature of the sealing portion.

[0029] The maleimide compound (A) preferably contains a maleimide compound (a1) having a melting point of 150°C or lower. In this case, the fluidity of the composition (X) during molding can be increased, thereby improving the moldability of the composition (X). Furthermore, particularly when producing a solid composition (X), such as a powder, without using a solvent, the melting temperature of the kneaded mixture obtained by melt-kneading the maleimide compound (a1) with raw materials other than the maleimide compound (a1) can be lowered, thereby suppressing the progress of the curing reaction during the production of the composition (X). Producing the composition (X) without using a solvent can suppress the residual solvent in the composition (X), further suppressing decomposition of the cured product and the sealed portion at high temperatures. Furthermore, when producing the composition (X), it is easy to prepare a kneaded mixture of the maleimide compound (A) and the epoxy compound (B) in advance. By mixing this kneaded mixture with raw materials other than the kneaded mixture, the maleimide compound (A) can be well dispersed in the composition (X). This point will be explained again in the description of the production method of the composition (X).

[0030] The melting point of the maleimide compound (a1) is more preferably 130° C. or lower. The melting point of the maleimide compound (a1) is, for example, 50° C. or higher.

[0031] The maleimide compound (A) may contain only the maleimide compound (a1). In order to easily prepare a kneaded product of the maleimide compound (A) and the epoxy compound (B), the ratio of the maleimide compound (a1) to the maleimide compound (A) is preferably 50% by mass or more and 100% by mass or less. The ratio of the maleimide compound (a1) is more preferably 70% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more. A ratio of 100% by mass is most preferred.

[0032] The maleimide compound (a1) preferably contains a maleimide compound (a11) having a structure represented by the following formula (3):

[0033]

[0034] In formula (3), n is a number of 1 to 5, m is a number of 1 to 5, and R is H, CH ３ or C ２ H５ is.

[0035] The maleimide compound (a11) can achieve a melting point of 150°C or less, and can further increase the glass transition temperature of the cured product and the sealing portion. That is, when n is 5 or less, the glass transition temperature can be further increased. It is more preferable that n is 3 or less, and even more preferable that n is 1. Furthermore, when m is 5 or less, the melting point of the maleimide compound (a11) can be achieved to be 150°C or less. It is more preferable that m is 3 or less, and even more preferable that m is 1. Furthermore, when R is H, CH ３ or C ２ H ５ In this case, good reactivity of the maleimide compound (a11) can be ensured. Note that the multiple Rs in the molecule of the maleimide compound (a11) may be the same or different from each other.

[0036] The proportion of the maleimide compound (a1) relative to the total of the maleimide compound (A), the epoxy compound (B), and the phenol compound (C) is preferably 15% by mass or more and 75% by mass or less. If the proportion is 15% by mass or more, the glass transition temperature of the cured product and the sealed portion can be further increased. If the proportion is 75% by mass or less, the cured product and the sealed portion become less susceptible to decomposition at high temperatures. A proportion of 30% by mass or more is more preferable. Also, a proportion of 60% by mass or less is more preferable.

[0037] The maleimide compound (A) may contain only the maleimide compound (a11), or may contain the maleimide compound (a11) and a compound other than the maleimide compound (a11). The ratio of the maleimide compound (a11) to the maleimide compound (A) is preferably 50% by mass or more and 100% by mass or less. The ratio of the maleimide compound (a11) is more preferably 70% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more. A ratio of 100% by mass is most preferred.

[0038] The epoxy compound (B) will now be described. When the epoxy compound (B) contains the epoxy compound (b1) having the structure shown in formula (1), the cured product and the sealing portion can have an appropriate crosslinking density, which increases the glass transition temperatures of the cured product and the sealing portion and makes the cured product and the sealing portion less susceptible to decomposition at high temperatures.

[0039] That is, when m in formula (1) is 1 or more, the cured product and the sealing portion are less likely to decompose at high temperatures, and when m is 6 or less, the glass transition temperature of the cured product and the sealing portion can be increased. m is more preferably 3 or less. Furthermore, when n in formula (1) is 1 or more, the glass transition temperature of the cured product and the sealing portion can be increased. Furthermore, when n is 5 or less, an excessive increase in the melt viscosity of composition (X) can be suppressed, thereby ensuring good moldability of composition (X). It is more preferable that n is 2 or more. Furthermore, it is more preferable that n is 3 or less.

[0040] The proportion of the epoxy compound (b1) relative to the total of the maleimide compound (A), the epoxy compound (B), and the phenol compound (C) is preferably 15% by mass or more and 70% by mass or less. When this proportion is 15% by mass or more, the cured product and the sealed portion are less likely to decompose at high temperatures. When this proportion is 70% by mass or less, the glass transition temperatures of the cured product and the sealed portion can be further increased. It is more preferable that this proportion is 30% by mass or more. It is more preferable that this proportion is 60% by mass or less.

[0041] The epoxy compound (B) may contain only the epoxy compound (b1), or may contain the epoxy compound (b1) and a compound other than the epoxy compound (b1) (hereinafter referred to as the epoxy compound (b2)). The ratio of the epoxy compound (b1) to the epoxy compound (B) is preferably 50% by mass or more and 100% by mass or less. This ratio is more preferably 70% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more. A ratio of 100% by mass is most preferred.

[0042] When the epoxy compound (B) contains an epoxy compound (b2), the epoxy compound (b2) may contain any of a monomer, an oligomer, a prepolymer, etc. The epoxy compound (b2) may contain at least one component selected from the group consisting of, for example, a glycidylamine-type epoxy resin, a glycidyl ester-type epoxy resin, and an olefin-oxidized (alicyclic) epoxy resin. More specifically, the epoxy compound (b2) may be, for example, an alkylphenol novolac-type epoxy resin such as a phenol novolac-type epoxy resin or a cresol novolac-type epoxy resin; a naphthol novolac-type epoxy resin; a phenol aralkyl-type epoxy resin having a skeleton such as a phenylene skeleton or a biphenylene skeleton; a biphenyl aralkyl-type epoxy resin; a naphthol aralkyl-type epoxy resin having a skeleton such as a phenylene skeleton or a biphenylene skeleton; a polyfunctional epoxy resin such as a triphenolmethane-type epoxy resin or an alkyl-modified triphenolmethane-type epoxy resin; a triphenylmethane-type epoxy resin; a tetrakisphenolethane-type epoxy resin; a dicyclopentadiene-type epoxy resin; bisphenol-type epoxy resins such as bisphenol A-type epoxy resins and bisphenol F-type epoxy resins; biphenyl-type epoxy resins; biphenyl alkyl-type epoxy resins; naphthalene-type epoxy resins; alicyclic epoxy resins; bromine-containing epoxy resins such as bisphenol A-type bromine-containing epoxy resins; glycidylamine-type epoxy resins obtained by reacting epichlorohydrin with polyamines such as diaminodiphenylmethane and isocyanuric acid; and glycidyl ester-type epoxy resins obtained by reacting epichlorohydrin with polybasic acids such as phthalic acid and dimer acid.

[0043] The phenol compound (C) will now be described. When the phenol compound (C) contains the phenol compound (c1) having the structure shown in formula (2), the glass transition temperatures of the cured product and the sealed portion are increased, and the cured product and the sealed portion become less susceptible to decomposition at high temperatures.

[0044] In formula (2), when n is 1 or more, the glass transition temperature of the cured product and the sealed portion is increased. When n is 5 or less, an excessive increase in the melt viscosity of composition (X) is suppressed, thereby ensuring good moldability of composition (X). It is more preferable that n is 3 or less, and even more preferable that n is 1.

[0045] In formula (2), R is H, CH ３ , O.H., C. ６ H ５ or C ６ H ４ The presence of OH allows the cured product and the sealing portion to have an appropriate crosslink density, which increases the glass transition temperature of the cured product and the sealing portion and makes the cured product and the sealing portion less susceptible to decomposition at high temperatures.

[0046] In formula (2), when X is a structure represented by the following formula (21), formula (22), or formula (23), the glass transition temperatures of the cured product and the sealing portion can be increased, and the cured product and the sealing portion can have an appropriate crosslinking density.

[0047] The proportion of the phenol compound (c1) relative to the total of the maleimide compound (A), the epoxy compound (B), and the phenol compound (C) is preferably 5% by mass or more and 30% by mass or less. When this proportion is 5% by mass or more, the composition (X) can have good reactivity. When this proportion is 30% by mass or less, the cured product and the sealed portion are less likely to decompose at high temperatures. This proportion is more preferably 10% by mass or more. Furthermore, this proportion is more preferably 20% by mass or less.

[0048] The phenol compound (C) may contain only the phenol compound (c1), or may contain the phenol compound (c1) and a compound other than the phenol compound (c1) (hereinafter referred to as the phenol compound (c2)). The ratio of the phenol compound (c1) to the phenol compound (C) is preferably 50% by mass or more and 100% by mass or less. This ratio is more preferably 70% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more. A ratio of 100% by mass is most preferred.

[0049] When the phenol compound (C) contains a phenol compound (c2), the phenol compound (c2) may contain any of a monomer, an oligomer, and a prepolymer. The phenol compound (c2) may contain at least one component selected from the group consisting of novolak resins such as phenol novolak resins, cresol novolak resins, and naphthol novolak resins; phenol aralkyl resins having a phenylene skeleton or a biphenylene skeleton; aralkyl resins such as naphthol aralkyl resins having a phenylene skeleton or a biphenylene skeleton; polyfunctional phenol resins such as triphenolmethane resins; dicyclopentadiene phenol resins such as dicyclopentadiene phenol novolak resins and dicyclopentadiene naphthol novolak resins; terpene-modified phenol resins; bisphenol resins such as bisphenol A and bisphenol F; and triazine-modified novolak resins.

[0050] The inorganic filler (D) can reduce the thermal expansion coefficient of the cured product and the sealing portion, making the semiconductor device including the sealing portion less susceptible to thermal deformation. Furthermore, the inorganic filler (D) can improve the heat resistance of the cured product and the sealing portion.

[0051] The inorganic filler (D) can contain at least one component selected from the group consisting of fused silica powder, such as fused spherical silica powder, crystalline silica powder, alumina powder, and silicon nitride powder. It is particularly preferred that the inorganic filler (D) contains fused silica powder. This facilitates achieving high filling of the inorganic filler (D) in the composition (X) and high fluidity of the composition (X) during molding. The inorganic filler (D) may also contain other suitable inorganic material powders.

[0052] The inorganic filler (D) has an average particle size of, for example, 5 μm or more and 30 μm or less. The average particle size is the cumulative 50% diameter (median diameter D50) calculated from the volume-based particle size distribution measured by a laser diffraction / scattering method. The inorganic filler (D) may contain two or more components with different average particle sizes in order to adjust the viscosity of the composition (X) during molding, the physical properties of the sealing portion, etc.

[0053] The ratio of inorganic filler (D) to composition (X) is preferably 70% by mass or more and 95% by mass or less. If the ratio is 70% by mass or more, the thermal expansion coefficient of the sealing portion is easily sufficiently reduced, and deformation such as warping is less likely to occur in the semiconductor device 1. If this ratio is 80% by mass or more, it is more preferable. If this ratio is 95% by mass or less, sufficient fluidity of composition (X) during molding is easily obtained. If this ratio is 85% by mass or less, it is more preferable.

[0054] It is preferable that the composition (X) further contains a melamine compound (E). In this case, the glass transition temperature of the cured product and the sealed portion can be further increased. Furthermore, even if a low-polymerization component of the maleimide compound (A) is generated when the composition (X) is cured, the low-polymerization component of the maleimide compound (A) reacts with the melamine compound (E), thereby suppressing the residue of the low-polymerization component of the maleimide compound (A) in the cured product and the sealed portion.

[0055] The melamine compound (E) preferably contains a methylolmelamine compound (e1) having the structure shown in the following formula (4): In this case, the glass transition temperatures of the cured product and the sealed portion are further increased, and decomposition of the cured product and the sealed portion at high temperatures can be further suppressed.

[0056]

[0057] In formula (4), R1, R2, and R3 each independently represent H or CH ２ OH, and at least one of R1, R2, and R3 is CH ２ It's OH.

[0058] The melamine compound (E) may contain only the methylol melamine compound (e1), may contain the methylol melamine compound (e1) and a compound other than the methylol melamine compound (e1), or may contain only a compound other than the methylol melamine compound (e1). The ratio of the methylol melamine compound (e1) to the melamine compound (E) is preferably 50% by mass or more and 100% by mass or less. This ratio is more preferably 70% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more. A ratio of 100% by mass is most preferred.

[0059] When the composition (X) contains the methylol melamine compound (e1), the proportion of the methylol melamine compound (e1) relative to the total of the maleimide compound (A), the epoxy compound (B), the phenol compound (C), and the melamine compound (E) is preferably 0.5% by mass or more and 10% by mass or less. When this proportion is 0.5% by mass or more, the glass transition temperature of the cured product and the sealed portion can be further increased. When this proportion is 10% by mass or less, decomposition of the cured product and the sealed portion at high temperatures can be further suppressed. It is more preferable that this proportion is 3% by mass or less.

[0060] Composition (X) may contain additives other than the above components within a range that does not excessively impair the effects of the embodiment. The additives may include, for example, at least one selected from the group consisting of a curing accelerator, a coupling agent, an ion trapping agent, a flame retardant, a colorant, a stress reducing agent, and a tackifier.

[0061] The release agent may contain at least one component selected from the group consisting of carnauba wax, stearic acid, montanic acid, carboxyl group-containing polyolefin, ester wax, polyethylene oxide, and metal soap.

[0062] The coupling agent can improve the affinity between the inorganic filler (D) and the epoxy compound (B) and phenol compound (C). The coupling agent can also improve the adhesion of the sealing portion 62 to the lead frame 52. For example, a silane coupling agent is used as the coupling agent. The silane coupling agent contains at least one component selected from the group consisting of glycidoxysilanes such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, etc.; aminosilanes such as N-β(aminoethyl)-γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, and N-phenyl-γ-aminopropyltrimethoxysilane; alkylsilanes; ureidosilanes; and vinylsilanes.

[0063] The flame retardant may contain, for example, at least one component selected from the group consisting of magnesium hydroxide, aluminum hydroxide, and red phosphorus.

[0064] The colorant may contain, for example, at least one component selected from the group consisting of carbon black, red iron oxide, titanium oxide, phthalocyanine, and perylene black.

[0065] The stress reducing agent may contain at least one component selected from the group consisting of silicone elastomer, silicone resin, silicone oil, and butadiene-based rubber. The butadiene-based rubber may contain at least one component selected from the group consisting of methyl acrylate-butadiene-styrene copolymer and methyl methacrylate-butadiene-styrene copolymer.

[0066] Examples of the curing catalyst include imidazoles such as 2-methylimidazole, 2-ethylimidazole, 2-phenylimidazole, and 2-ethyl-4-methylimidazole; cycloamidines such as 1,8-diazabicyclo[5.4.0]undecene-7, 1,5-diazabicyclo[4.3.0]nonene-5, and 5,6-dibutylamino-1,8-diazabicyclo[5.4.0]undecene-7; tertiary amines such as 2-(dimethylaminomethyl)phenol, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol; tributylphosphine, methyldiphenylphosphine, and triphenylphosphine. organic phosphines such as phenylphosphine, tris(4-methylphenyl)phosphine, diphenylphosphine, an addition reaction product of triphenylphosphine and parabenzoquinone, and phenylphosphine; tetra-substituted phosphonium and tetra-substituted borates such as tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium ethyltriphenylborate, and tetrabutylphosphonium tetrabutylborate; quaternary phosphonium salts having a counter anion other than borate; and tetraphenylboron salts such as 2-ethyl-4-methylimidazole tetraphenylborate and N-methylmorpholine tetraphenylborate.

[0067] It is preferable that composition (X) does not contain a solvent. When composition (X) contains a solvent, the ratio of the solvent to composition (X) is preferably 1 mass% or less. In this case, residual solvent in the cured product and the sealed portion can be suppressed, and therefore decomposition of the cured product and the sealed portion at high temperatures can be further suppressed.

[0068] The method for producing the composition (X) will be described.

[0069] The composition (X) is preferably solid. The composition (X) is produced, for example, by mixing the raw materials of the composition (X), melt-kneading the mixture, and then powdering, pelletizing, or tableting the mixture as necessary. For example, the raw materials of the composition (X) are mixed using a mixer or the like, then melt-kneaded using a mixing roll, kneader, extruder, or the like, and then cooled and pulverized to produce the composition (X).

[0070] Composition (X) may contain the maleimide compound (A) and the epoxy compound (B) in the form of a maleimide-epoxy kneaded product, which is a kneaded product of the maleimide compound (A) and the epoxy compound (B). In this case, when producing composition (X), it is preferable to mix the maleimide-epoxy kneaded product, which is a kneaded product of the maleimide compound (A) and the epoxy compound (B), with the phenolic compound (C) and the inorganic filler (D). In this case, the glass transition temperatures of the cured product and the sealing portion can be further increased, and decomposition of the cured product and the sealing portion at high temperatures can be further suppressed. This is presumably because, during the production process of composition (X), the maleimide compound (A) can be well dispersed in composition (X) while suppressing the reaction between each of the maleimide compound (A) and the epoxy compound (B) and the phenolic compound (C). It is also presumed that in the process of preparing the maleimide-epoxy kneaded product, the self-polymerization of the maleimide compound (A) and the self-polymerization of the epoxy compound (B) proceed to a certain extent, and therefore low-molecular-weight components are less likely to remain in the cured product and the sealed portion.

[0071] The maleimide-epoxy kneaded product is produced by melt-kneading the maleimide compound (A) and the epoxy compound (B). The heating temperature when melt-kneading the maleimide compound (A) and the epoxy compound (B) may be any appropriate temperature that can melt the maleimide compound (A) and the epoxy compound (B). The heating temperature is preferably 130°C or higher and 170°C or lower. In this case, the maleimide compound (A) can be sufficiently dispersed in the maleimide-epoxy kneaded product while allowing the self-polymerization of the maleimide compound (A) and the self-polymerization of the epoxy compound (B) to proceed appropriately.

[0072] A mixture is prepared by mixing the maleimide-epoxy kneaded product, the phenol compound (C), and the inorganic filler (D). When the composition (X) contains components other than those described above, the components other than those described above are also included in the mixture. The composition (X) can be produced by melt-kneading this mixture. The heating temperature during melt-kneading the mixture is preferably lower than the heating temperature during preparation of the maleimide-epoxy kneaded product, and is preferably 100°C or higher and 130°C or lower. In this case, the maleimide compound (A) can be well dispersed in the composition (X) while suppressing the reaction between each of the maleimide compound (A) and the epoxy compound (B) and the phenol compound (C). The composition (X) may be pulverized to prepare a powdered composition (X). The powdered composition (X) may be tableted to prepare a pelleted composition (X).

[0073] Preferred physical properties of the composition (X) will be described.

[0074] The spiral flow length of composition (X) is preferably 70 cm or more. In this case, composition (X) can have good moldability. The spiral flow length is measured by the method described in the Examples section below.

[0075] The gel time of composition (X) is preferably 25 seconds or more. In this case, composition (X) can have good moldability. The gel time is measured by the method described in the Examples section below.

[0076] By increasing the glass transition temperature of the cured product of composition (X), the glass transition temperature of the cured product is preferably 200°C or higher. In this case, the heat resistance of the cured product and the sealed portion can be further improved. A glass transition temperature of 250°C or higher is more preferable. The glass transition temperature is measured by the method described in the Examples section below.

[0077] By suppressing decomposition of the cured product of composition (X) at high temperatures, the weight loss rate of the cured product upon heating is preferably 2.0% or less, and more preferably 1.7% or less. The weight loss rate is measured by the method described in the Examples section below.

[0078] A semiconductor device having a sealing portion will be described. A semiconductor device 1 has a semiconductor element and a sealing portion that seals the semiconductor element, and the sealing portion includes a cured product of a composition (X).

[0079] There is no limitation on the type of the semiconductor device 1. Examples of the semiconductor device 1 include a single in-line package (SIP), a zigzag in-line package (ZIP), a dual in-line package (DIP), a small outline package (SOP), a small outline J-lead package (SOJ), a small outline I-lead package (SOI), a small outline F-lead package (SOF), a quad flat package (QFP), a quad flat J-lead package (QFJ), a quad flat I-lead package (QFI), and a quad Examples include a flat F-lead package (QFF), a pin grid array (PGA), a plastic ball grid array (PBGA), a fine pitch ball grid array (FBGA), a wafer level package (WLP), a panel level package (PLP), a fan-out wafer level package (FO-WLP), a fan-out panel level package (FO-PLP), a flip chip ball grid array (FC-BGA), an antenna-in-package (AiP), or a system-in-package (SiP).

[0080] The semiconductor device may be a heat-generating component such as a power semiconductor device. In this case, since decomposition of the sealing portion at high temperatures is suppressed, the reliability of the semiconductor device can be ensured even if the semiconductor device is a heat-generating component.

[0081] The semiconductor device may be for use in a vehicle. In this case, the semiconductor device for use in a vehicle is often exposed to a high-temperature atmosphere, but since decomposition of the sealing portion at high temperatures is suppressed, the reliability of the semiconductor device can be ensured.

[0082] The semiconductor element in the semiconductor device is, for example, an integrated circuit, a large-scale integrated circuit, a transistor, a thyristor, a diode, or a solid-state imaging element. The semiconductor element may be a SiC (silicon carbide) semiconductor. In this case, since the semiconductor element has high heat resistance, even if the semiconductor device generates heat or is exposed to high temperatures, not only is decomposition of the sealing portion suppressed, but malfunctions of the semiconductor element are also unlikely to occur. Therefore, the semiconductor device can have higher reliability. Furthermore, the semiconductor element is, for example, a power semiconductor element. In this case, since decomposition of the sealing portion at high temperatures is suppressed, the reliability of the semiconductor device can be ensured even if the power semiconductor element generates heat.

[0083] 1 shows an example of a semiconductor device 1. This semiconductor device 1 includes a metal lead frame 52, a semiconductor element 50 mounted on the lead frame 52, wires 56 that electrically connect the semiconductor element 50 and the lead frame 52, and a sealing portion 62 that seals the semiconductor element 50.

[0084] The lead frame 52 includes a paddle 58 (also called a die pad) and lead fingers 520. The semiconductor element 50 is fixed onto the paddle 58 of the lead frame 52 with a die bond material 60. In this way, the semiconductor element 50 is mounted on the lead frame 52. The semiconductor element 50 and the lead fingers 520 of the lead frame 52 are connected by wires 56.

[0085] The encapsulation portion 62 encapsulates the semiconductor element 50 , the wires 56 and the paddle 58 , and also partially encapsulates the lead fingers 520 .

[0086] 1 also includes a heat dissipation structure. The heat dissipation structure includes a heat sink 71 and a thermally conductive sheet 72. The heat sink 71 is made of a metal such as copper. The thermally conductive sheet 72 is made of an appropriate thermally conductive material (thermally conductive interface material: TIM). The surface of the paddle 58 opposite the semiconductor element 50 is overlapped with the heat sink 71 via the thermally conductive sheet 72. In the heat dissipation structure, the surface of the heat sink 71 opposite the paddle 58 is exposed to the outside through the sealing portion 62, and the remaining portion is sealed by the sealing portion 62.

[0087] The sealing portion 62 can be produced, for example, by molding the composition (X) by pressure molding. Pressure molding is, for example, injection molding, transfer molding, or compression molding. When molding the composition (X) by pressure molding, the molding pressure is preferably 3.0 MPa or more, and the molding temperature is preferably 150°C or more. In particular, in the case of transfer molding, the injection pressure of the composition (X) into the mold is preferably 5.0 MPa or more, and more preferably 7.0 MPa or more and 15.0 MPa or less. Furthermore, the heating temperature (mold temperature) is preferably 150°C or more, more preferably 170°C or more, and even more preferably 180°C or more and 200°C or less. Furthermore, the heating time is preferably 30 seconds or more and 300 seconds or less, and more preferably 60 seconds or more and 180 seconds or less.

[0088] In the transfer molding method, it is preferable that after the sealing portion 62 is formed in a mold, the sealing portion 62 is heated with the mold closed to post-cure, and then the mold is opened to remove the semiconductor device 1. The heating conditions for post-cure are, for example, a heating time of 160° C. to 190° C. and a heating time of 2 hours to 8 hours.

[0089] In the case of compression molding, the compression pressure is preferably 3.0 MPa or more, more preferably 5.0 MPa or more and 10.0 MPa or less. The heating temperature (mold temperature) is preferably 120°C or more, more preferably 150°C or more and 185°C or less. The heating time is preferably 60 seconds or more and 300 seconds or less.

[0090] The structure shown in FIG. 1 is merely one example of the semiconductor device 1. For example, the semiconductor device 1 may have a heat dissipation structure different from that shown in FIG. 1, or the semiconductor device 1 may not have a heat dissipation structure. Furthermore, electrical connection between the semiconductor element 50 and the lead frame 52 in the semiconductor device 1 may be achieved by a clip electrode or the like. The semiconductor device 1 may have any other appropriate structure. For example, the semiconductor device 1 is an in-vehicle module, and may have any appropriate structure suitable for that purpose.

[0091] [Aspects] The semiconductor encapsulating resin composition according to a first aspect contains a maleimide compound (A), an epoxy compound (B) containing an epoxy compound (b1) having a structure represented by the following formula (1), a phenol compound (C) containing a phenol compound (c1) having a structure represented by the following formula (2), and an inorganic filler (D).

[0092]

[0093]

[0094] In formula (1), n ​​is a number from 1 to 5, and m is a number from 1 to 6. In formula (2), n is a number from 1 to 5, and R is H, CH ３ , O.H., C. ６ H ５ or C ６ H ５ OH and X are a structure represented by the following formula (21), a structure represented by the following formula (22), or a structure represented by the following formula (23).

[0095]

[0096] According to this embodiment, a resin composition for semiconductor encapsulation can be obtained which can be used to produce an encapsulating part for encapsulating a semiconductor element, which can have a high glass transition point and can have improved long-term heat resistance of the encapsulating part.

[0097] In the second embodiment, the maleimide compound (A) in the first embodiment contains a maleimide compound (a1) having a melting point of 150° C. or lower.

[0098] According to this embodiment, the moldability of the semiconductor encapsulating resin composition can be improved.

[0099] In a third aspect, in the second aspect, the maleimide compound (a1) contains a maleimide compound (a11) having a structure represented by the following formula (3):

[0100]

[0101] In formula (3), n is a number of 1 to 5, m is a number of 1 to 5, and R is H, CH ３ or C ２ H ５ is.

[0102] According to this embodiment, the maleimide compound (a11) can have a low melting point, and the glass transition temperature of the cured product of the semiconductor encapsulating resin composition can be further increased.

[0103] In a fourth aspect, in any one of the first to third aspects, the semiconductor encapsulating resin composition contains a melamine compound (E) containing a methylol melamine compound (e1) having a structure represented by the following formula (4):

[0104]

[0105] In formula (4), R1, R2, and R3 each independently represent H or CH ２ OH, and at least one of R1, R2, and R3 is CH ２ It's OH.

[0106] According to this embodiment, the glass transition temperature of the cured product of the semiconductor encapsulating resin composition can be further increased, and decomposition of the cured product at high temperatures can be further suppressed.

[0107] In a fifth aspect, in any one of the first to fourth aspects, the proportion of the maleimide compound (a1) with respect to the total of the maleimide compound (A), the epoxy compound (B), and the phenol compound (C) is 15 mass% or more and 75 mass% or less.

[0108] According to this embodiment, the glass transition temperature of the cured product of the semiconductor encapsulating resin composition can be further increased, and decomposition of the cured product at high temperatures can be further suppressed.

[0109] In a sixth aspect, in any one of the first to fifth aspects, a ratio of the epoxy compound (b1) to the total of the maleimide compound (A), the epoxy compound (B), and the phenol compound (C) is 15% by mass or more and 70% by mass or less.

[0110] According to this embodiment, the glass transition temperature of the cured product of the semiconductor encapsulating resin composition can be further increased, and decomposition of the cured product at high temperatures can be further suppressed.

[0111] In a seventh aspect, in any one of the first to sixth aspects, the proportion of the phenol compound (c1) with respect to the total of the maleimide compound (A), the epoxy compound (B), and the phenol compound (C) is 5% by mass or more and 30% by mass or less.

[0112] According to this embodiment, the glass transition temperature of the cured product of the semiconductor encapsulating resin composition can be further increased, and decomposition of the cured product at high temperatures can be further suppressed.

[0113] In an eighth aspect, in any one of the first to seventh aspects, a ratio of the methylol melamine compound (e1) to the total of the maleimide compound (A), the epoxy compound (B), the phenol compound (C), and the melamine compound (E) is 0.5 mass% or more and 10 mass% or less.

[0114] According to this embodiment, the glass transition temperature of the cured product of the semiconductor encapsulating resin composition can be further increased, and decomposition of the cured product at high temperatures can be further suppressed.

[0115] In a ninth aspect, in any one of the first to eighth aspects, the semiconductor encapsulating resin composition contains the maleimide compound (A) and the epoxy compound (B) in the form of a maleimide-epoxy kneaded product which is a kneaded product of the maleimide compound (A) and the epoxy compound (B).

[0116] According to this embodiment, the maleimide compound (A) can be dispersed well in the semiconductor encapsulation resin composition.

[0117] A method for producing a semiconductor encapsulating resin composition according to a tenth aspect is a method for producing the semiconductor encapsulating resin composition according to any one of the first to ninth aspects. This method includes mixing a maleimide-epoxy kneaded mixture, which is a kneaded mixture of a maleimide compound (A) and an epoxy compound (B), with a phenol compound (C) and an inorganic filler (D).

[0118] According to this embodiment, the maleimide compound (A) can be dispersed well in the semiconductor encapsulation resin composition.

[0119] A semiconductor device (1) according to an eleventh aspect includes a semiconductor element (50) and an encapsulating portion (62) that encapsulates the semiconductor element (50). The encapsulating portion (62) includes a cured product of the semiconductor encapsulation resin composition according to any one of the first to ninth aspects.

[0120] The semiconductor device (1) according to a twelfth aspect is the eleventh aspect, wherein the semiconductor element (50) is a power semiconductor element.

[0121] Specific examples of this embodiment are presented below, but the present disclosure is not limited to these examples.

[0122] 1. Preparation of Resin Compositions In Examples 1, 3 to 7, and Comparative Example 1, the raw materials shown in the "Composition" column of Table 1 were blended and mixed uniformly in a mixer, and then melt-kneaded using a twin-screw kneader at a material temperature of 120°C to obtain compositions. The compositions were cooled, pulverized, and further compressed into tablets to obtain tablet-shaped compositions.

[0123] In Example 2, the maleimide compound and the epoxy compound #1 were mixed in a mass ratio of 50:50 and melt-mixed in a metal container at 150° C. to obtain a maleimide-epoxy mixture.

[0124] The raw materials shown in the "Composition" column of Table 1, including this maleimide-epoxy kneaded product, were blended and mixed uniformly in a mixer, and then melt-kneaded using a twin-screw kneader at a material temperature of 120° C. to obtain a composition. This composition was cooled, pulverized, and further tableted to obtain a tablet-shaped composition.

[0125] Details of the components shown in Table 1 are as follows. The percentages shown in parentheses in the "Composition" column in Table 1 are the percentages relative to the total of the maleimide compound, epoxy compound, phenol compound, and methylolmelamine compound in the composition. Maleimide compound: A maleimide compound represented by the following formula. Manufactured by Daiwa Kasei Co., Ltd. Product name: BMI-2300.

[0126]

[0127] Epoxy compound #1: an epoxy compound represented by the following formula, where n is 1. Manufactured by Nippon Kayaku Co., Ltd. Product name: NC-3000.

[0128]

[0129] Epoxy compound #2: Triphenylmethane type epoxy resin, manufactured by Nippon Kayaku Co., Ltd. Product name: EPPN-501HY. Phenol compound: Phenol compound represented by the following formula, manufactured by UBE Co., Ltd. Product name: MKH-7000.

[0130] Inorganic filler: fused spherical silica, manufactured by Denka Co., Ltd., product name FB-910. Methylolmelamine compound: a methylolmelamine compound represented by the following formula, manufactured by Nissan Chemical Industries, Ltd., product name CP-9071SD.

[0131]

[0132] - Curing accelerator: 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine. - Mold release agent: natural carnauba wax. - Colorant: carbon black. - Silane coupling agent: N-phenyl-3-aminopropyltrimethoxysilane. Manufactured by Dow Toray Industries, Inc. Product name: Z-6883. - Stress reducing agent: polydimethylsilsesquioxane.

[0133] 2. Evaluation The following evaluation tests were carried out.

[0134] (1) Spiral flow length: According to ASTM D3123, a spiral flow mold was used, the molding temperature was 170°C, and the injection pressure was 70 kgf / cm. ２ The composition was molded under the conditions of 180 seconds molding time, and the distance that the composition flowed (flow distance) for 180 seconds from the start of molding was measured.

[0135] (2) Gel Time Using a Curastometer testing device (manufactured by JSR Corporation, product name: Curastometer III PS type), the surface temperatures of both the upper and lower sides of a mold were set to 170°C, and 1.67 mL of a sample of the resin composition of each of the Examples and Comparative Examples was added to measure the torque value. The time required for the torque value to reach 0.1 kgf cm was read as the gel time.

[0136] (3) Glass Transition Temperature The composition was molded under conditions of a mold temperature of 185°C and a heating time of 180 seconds, and then post-cured under conditions of a heating temperature of 200°C and a heating time of 4 hours, to prepare an evaluation sample having a diameter of 5 mm and a thickness of 15 mm.

[0137] This sample was measured using a thermomechanical analyzer under conditions of a temperature rise rate of 5° C. / min and a load of 0.049 N, and the glass transition temperature was determined from the results.

[0138] (4) Weight Loss Rate The composition was molded under conditions of a mold temperature of 185°C and a heating time of 180 seconds, and then post-cured under conditions of a heating temperature of 200°C and a heating time of 4 hours, to prepare an evaluation sample having dimensions of 80 mm × 10 mm × 4 mm.

[0139] This sample was left to stand for 1000 hours in a thermostatic chamber at 250° C. The initial weight of the sample was measured as W0, and the weight of the sample after it was placed in the thermostatic chamber was measured as W1. The weight loss rate of the sample was calculated using the following formula:

[0140] Weight reduction rate = [(W0-W1) / W0] x 100 (%)

[0141]

[0142] 1 semiconductor device 50 semiconductor element 62 sealing portion

Claims

1. Maleimide compound (A) and An epoxy compound (B) containing an epoxy compound (b1) having the structure shown in formula (1) below, A phenol compound (C) containing a phenol compound (c1) having the structure shown in formula (2) below, It contains an inorganic filler (D), 【Chemistry 1】 【Chemistry 2】 In equation (1), n ​​is a number between 1 and 5 (inclusive), and m is a number between 1 and 6 (inclusive). In equation (2), n is a number between 1 and 5 (inclusive), and R is H, CH ３ OH, C ６ H ５ or C ６ H ４ OH and X have the structure shown in formula (21), formula (22), or formula (23) below. 【Transformation 3】 Resin composition for semiconductor encapsulation.

2. The maleimide compound (A) contains a maleimide compound (a1) having a melting point of 150°C or less. The semiconductor encapsulation resin composition according to claim 1.

3. The maleimide compound (a1) contains a compound (a11) having the structure shown in the following formula (3), 【Chemistry 4】 In equation (3), n is a number between 1 and 5 (inclusive), m is a number between 1 and 5 (inclusive), and R is H, CH ３ or C ２ H ５ That is, The semiconductor encapsulation resin composition according to claim 2.

4. It contains a melamine compound (E) which contains a methylolmelamine compound (e1) having the structure shown in formula (4) below, 【Transformation 5】 In formula (4), R1, R2, and R3 are each independently H or CH ２ OH, and at least one of R1, R2, and R3 is CH ２ OH A resin composition for semiconductor encapsulation according to any one of claims 1 to 3.

5. The ratio of the maleimide compound (a1) to the total of the maleimide compound (A), the epoxy compound (B), and the phenol compound (C) is 15% by mass or more and 75% by mass or less. A resin composition for semiconductor encapsulation according to any one of claims 1 to 3.

6. The proportion of the epoxy compound (b1) to the sum of the maleimide compound (A), the epoxy compound (B), and the phenol compound (C) is 15% by mass or more and 70% by mass or less. A resin composition for semiconductor encapsulation according to any one of claims 1 to 3.

7. The proportion of the phenol compound (c1) to the sum of the maleimide compound (A), the epoxy compound (B), and the phenol compound (C) is 5% by mass or more and 30% by mass or less. A resin composition for semiconductor encapsulation according to any one of claims 1 to 3.

8. The ratio of the methylolmelamine compound (e1) to the sum of the maleimide compound (A), the epoxy compound (B), the phenol compound (C), and the melamine compound (E) is 0.5% by mass or more and 10% by mass or less. The semiconductor encapsulation resin composition according to claim 4.

9. The maleimide compound (A) and the epoxy compound (B) are contained in the form of a maleimide-epoxy mixture, which is a mixture of the maleimide compound (A) and the epoxy compound (B). A resin composition for semiconductor encapsulation according to any one of claims 1 to 3.

10. A method for producing a semiconductor encapsulation resin composition according to any one of claims 1 to 3, comprising mixing a maleimide-epoxy compound, which is a mixture of the maleimide compound (A) and the epoxy compound (B), the phenol compound (C), and the inorganic filler (D), A method for producing a resin composition for semiconductor encapsulation.

11. The device comprises a semiconductor element and a sealing portion that seals the semiconductor element. The sealing portion includes a cured product of the semiconductor encapsulation resin composition according to any one of claims 1 to 3. Semiconductor equipment.

12. The aforementioned semiconductor device is a power semiconductor device. The semiconductor device according to claim 11.

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