Resin composition for semiconductor encapsulation and semiconductor device

Abstract

To provide a resin composition for semiconductor encapsulation that enables production of an encapsulating material exhibiting high dielectric breakdown voltage, resulting in long insulation life and superior reliability.SOLUTION: The resin composition for semiconductor encapsulation of the present invention comprises (A) an epoxy resin, (B) an inorganic filler, and (C) a carboxylic acid-based dispersant having a polycarboxylic acid as a main backbone, wherein the inorganic filler (B) includes alumina (b1) having an average particle diameter of 5 μm or more and 45 μm or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition for semiconductor encapsulation containing an epoxy resin and an inorganic filler, and to a semiconductor device. [Background technology]

[0002] BACKGROUND ART Resin compositions containing epoxy resins have been actively developed as semiconductor encapsulation resin compositions for encapsulating various electronic devices.

[0003] In recent years, power semiconductor devices have become smaller and larger in current. It is widely known that a large current can cause leakage current from circuits or elements, which can lead to failures in power semiconductor devices. Therefore, from the viewpoint of semiconductor device reliability, there is a strong demand for improved insulation in power semiconductor devices.

[0004] Cited Document 1 discloses a resin sheet for semiconductor encapsulation obtained by molding an epoxy resin composition containing an epoxy resin including a crystalline epoxy resin, a phenolic resin curing agent, a curing accelerator, an inorganic filler, and a polycarboxylic acid-based dispersing agent into a sheet shape.

[0005] Patent Document 2 discloses a resin composition for semiconductor encapsulation, which contains an epoxy resin, a curing agent, an inorganic filler, and a polymeric ionic dispersant having a polycarboxylic acid as its main skeleton. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-009814 [Patent Document 2] International Publication No. 2021 / 039809 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the sealing materials described in Patent Documents 1 and 2 have a low breakdown voltage, and therefore have a short insulation life, leaving room for improvement in product reliability. [Means for solving the problem]

[0008] Conventionally, there has been a problem in that gaps (voids) are generated between inorganic fillers in a cured product of a semiconductor encapsulation resin composition, and current leaks through these voids, resulting in a decrease in breakdown voltage. Therefore, the present inventors have discovered that increasing the average particle size of the inorganic filler reduces the specific surface area, making it difficult for voids to be generated between the inorganic filler particles, and further improving the wettability of the inorganic filler surface with a specific dispersant allows the resin to easily fill between the inorganic filler particles, making it even more difficult for voids to be generated between the inorganic filler particles, thereby increasing the breakdown voltage of the resulting cured product, and have completed the present invention.

[0009] That is, the present invention can be shown as follows. [1] (A) an epoxy resin; (B) an inorganic filler; (C) a carboxylic acid-based dispersant having a polycarboxylic acid as a main skeleton, A resin composition for semiconductor encapsulation, wherein the inorganic filler (B) contains alumina (b1) having an average particle size of 5 μm or more and 45 μm or less. [2] The resin composition for semiconductor encapsulation according to [1], comprising 0.05 parts by mass or more and 5 parts by mass or less of the carboxylic acid-based dispersant (C) per 100 parts by mass of the alumina (b1). [3] The resin composition for semiconductor encapsulation according to [1] or [2], wherein the inorganic filler (B) contains silica (b2). [4] The semiconductor encapsulating resin composition according to any one of [1] to [3], wherein the carboxylic acid-based dispersant (C) is a compound represented by the following general formula (1): [ka] (In general formula (1), R represents a hydrogen atom, a carboxyl group, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylcarboxyl group having 1 to 5 carbon atoms, an alkoxycarboxyl group having 1 to 5 carbon atoms, an alkyl alcohol group having 1 to 5 carbon atoms, or an alkoxy alcohol group having 1 to 5 carbon atoms, and multiple Rs may be the same or different. X represents an oxygen atom, an alkylene group having 1 to 30 carbon atoms, a divalent chain hydrocarbon group having 1 to 30 carbon atoms and having one or more double bonds, or a divalent chain hydrocarbon group having 1 to 30 carbon atoms and having one or more triple bonds, and multiple Xs may be the same or different. n represents an integer of 0 to 20, and m represents an integer of 1 to 5.) [5] The semiconductor encapsulating resin composition according to any one of [1] to [4], further comprising a curing agent (D). [6] The resin composition for semiconductor encapsulation according to any one of [1] to [5], further comprising a curing accelerator (E). [7] A semiconductor element mounted on a substrate; an encapsulant for encapsulating the semiconductor element, the encapsulant comprising a cured product of the semiconductor encapsulation resin composition according to any one of [1] to [6]; A semiconductor device comprising: [Effects of the Invention]

[0010] According to the present invention, it is possible to provide a resin composition for semiconductor encapsulation that can yield an encapsulant having a high dielectric breakdown voltage, a long insulation life, and excellent product reliability, and further to provide a semiconductor device that includes an encapsulant made of a cured product of the resin composition. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a schematic cross-sectional view of a semiconductor device according to an embodiment of the present invention; [Figure 2] 4 is a diagram illustrating a method for measuring a breakdown voltage in the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all drawings, similar components are denoted by similar reference numerals, and their description will be omitted where appropriate. For example, "1 to 10" represents "1 or more" to "10 or less" unless otherwise specified.

[0013] The semiconductor encapsulating resin composition of the present embodiment includes (A) an epoxy resin, (B) an inorganic filler, and (C) a carboxylic acid-based dispersant having a polycarboxylic acid as a main skeleton, The inorganic filler (B) contains alumina (b1) having an average particle size of 5 μm or more and 45 μm or less.

[0014] The semiconductor encapsulation resin composition of the present embodiment has a high breakdown voltage and a long insulation life, and therefore can provide an encapsulant with excellent product reliability, and can also provide a semiconductor device including the encapsulant. Furthermore, the semiconductor encapsulation resin composition has improved flowability and therefore excellent moldability. Each component will be described below.

[0015] [Epoxy resin (A)] The epoxy resin (A) includes one or more selected from triphenylmethane type epoxy resins, biphenyl aralkyl type polyfunctional epoxy resins, orthocresol type difunctional epoxy resins, biphenyl type difunctional epoxy resins, and bisphenol type difunctional epoxy resins.

[0016] From the viewpoint of the effects of the present invention, the epoxy resin (A) more preferably contains one or more selected from biphenylaralkyl-type multifunctional epoxy resins, biphenyl-type difunctional epoxy resins, and bisphenol A-type difunctional epoxy resins, and further preferably contains one or more selected from biphenylaralkyl-type multifunctional epoxy resins and biphenyl-type difunctional epoxy resins.

[0017] Specifically, triphenylmethane epoxy resins are epoxy resins containing a partial structure in which three of the four hydrogen atoms of methane (CH4) are replaced with benzene rings. The benzene rings may be unsubstituted or substituted with a substituent. Examples of the substituents include hydroxyl groups and glycidyloxy groups.

[0018] Specifically, the triphenylmethane type epoxy resin contains a structural unit represented by the following general formula (a1): Two or more of these structural units are connected together to form a triphenylmethane skeleton.

[0019] [ka]

[0020] In general formula (a1), R 11 When there are a plurality of groups, each group independently represents a monovalent organic group, a halogen atom, a hydroxy group, or a cyano group, R 12 When there are a plurality of groups, each group independently represents a monovalent organic group, a halogen atom, a hydroxy group, or a cyano group, i is an integer from 0 to 3, j is an integer of 0 to 4.

[0021] R 11 and R 12 Examples of the monovalent organic group include R in the general formula (BP) described below. a and R b Examples of the monovalent organic group include those listed as the monovalent organic group. i and j each independently represent preferably 0 to 2, and more preferably 0 to 1.

[0022] In one embodiment, both i and j are 0. That is, in one embodiment, none of the benzene rings in general formula (a1) has a monovalent substituent other than the explicitly stated glycidyloxy group.

[0023] Specifically, the biphenyl-containing epoxy resin is an epoxy resin containing a structure in which two benzene rings are connected by a single bond. The benzene rings may or may not have a substituent. Specifically, an epoxy resin containing a biphenyl structure has a partial structure represented by the following general formula (BP).

[0024] [ka]

[0025] In general formula (BP), R a and R b When there are a plurality of groups, each group independently represents a monovalent organic group, a hydroxyl group, or a halogen atom; r and s each independently represent 0 to 4; * indicates a bond to another atomic group.

[0026] R a and R b Specific examples of the monovalent organic group include an alkyl group, an alkenyl group, an alkynyl group, an alkylidene group, an aryl group, an aralkyl group, an alkaryl group, a cycloalkyl group, an alkoxy group, a heterocyclic group, and a carboxyl group.

[0027] Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a neopentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group.

[0028] Examples of the alkenyl group include an allyl group, a pentenyl group, and a vinyl group. The alkynyl group includes, for example, an ethynyl group. Examples of the alkylidene group include a methylidene group and an ethylidene group.

[0029] Examples of the aryl group include a tolyl group, a xylyl group, a phenyl group, a naphthyl group, and an anthracenyl group. Examples of the aralkyl group include a benzyl group and a phenethyl group. Examples of the alkaryl group include a tolyl group and a xylyl group. Examples of the cycloalkyl group include an adamantyl group, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group.

[0030] Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an s-butoxy group, an isobutoxy group, a t-butoxy group, an n-pentyloxy group, a neopentyloxy group, and an n-hexyloxy group. Examples of the heterocyclic group include an epoxy group and an oxetanyl group.

[0031] R a and R b The total number of carbon atoms in each of the monovalent organic groups is, for example, 1 to 30, preferably 1 to 20, more preferably 1 to 10, and particularly preferably 1 to 6. Each of r and s is independently preferably 0 to 2, more preferably 0 to 1. In one embodiment, both r and s are 0.

[0032] More specifically, the epoxy resin containing a biphenyl structure is preferably a biphenyl-type epoxy resin having glycidyl ether groups at both ends of the biphenyl structure, or a biphenylaralkyl-type epoxy resin having a structural unit represented by the following general formula (BP1).

[0033] [ka]

[0034] In general formula (BP1), R a and R bThe definition and specific embodiments of are the same as those of general formula (BP), The definitions and preferred ranges of r and s are the same as those in general formula (BP), R c When there are a plurality of groups, each group independently represents a monovalent organic group, a hydroxyl group, or a halogen atom;

[0035] t is an integer of 0 to 3. R c Specific examples of the monovalent organic group include R a and R b Examples of the above include those given as specific examples. t is preferably 0 to 2, and more preferably 0 to 1.

[0036] Specific examples of bisphenol-type epoxy resins (epoxy resins produced by a condensation reaction between bisphenol and epichlorohydrin) include epoxy resins represented by the following general formula (EP).

[0037] [ka]

[0038] In the general formula (EP), each of the plurality of R's independently represents a hydrogen atom or a methyl group, preferably a methyl group; R a , R b , R c and R d each, when a plurality of groups are present, is independently a monovalent organic group, a hydroxyl group, or a halogen atom; p, q, r, and s each independently represent an integer of 0 to 4, preferably 0 to 2; n is an integer of 0 or more, usually 0 to 10, and preferably 0 to 5.

[0039] R a , R b , R c and R dSpecific examples of the monovalent organic group include R in general formula (BP): a and R b Specific examples of the monovalent organic group include the same as those given above. In this embodiment, it is preferable to use a bisphenol A type epoxy resin in which R is a methyl group.

[0040] The content of the epoxy resin (A) in the semiconductor encapsulating resin composition is preferably 1% by mass or more, more preferably 2% by mass or more, and even more preferably 3% by mass or more, relative to 100% by mass of the entire semiconductor encapsulating resin composition, from the viewpoint of obtaining suitable fluidity during molding and improving filling properties and moldability.

[0041] Furthermore, from the viewpoint of improving the reliability of a semiconductor obtained by using the semiconductor encapsulation resin composition, the content of the epoxy resin (A) in the semiconductor encapsulation resin composition is preferably 15% by mass or less, more preferably 10% by mass or less, and even more preferably 8% by mass or less, relative to 100% by mass of the entire semiconductor encapsulation resin composition.

[0042] [Inorganic filler (B)] The inorganic filler (B) contains alumina (b1) and may further contain other inorganic fillers.

[0043] (Alumina (b1)) The alumina (b1) contained in the semiconductor encapsulating resin composition has an average particle diameter D at a cumulative frequency of 50% in a volume-based cumulative frequency distribution curve measured using a laser diffraction particle size distribution analyzer. 50 However, it can be set to 5 μm or more and 45 μm or less, preferably 6 μm or more and 40 μm or less, more preferably 7 μm or more and 30 μm or less, and even more preferably 8 μm or more and 20 μm or less.

[0044] By setting the average particle size of the alumina (b1) within the above range, the specific surface area becomes small, which makes it difficult for voids to occur between the alumina particles, resulting in a high breakdown voltage of the cured product, and also makes the filling property of the semiconductor encapsulating resin composition excellent during molding.

[0045] The mode diameter of the alumina (b1) can be preferably 2 μm or more and 50 μm or less, more preferably 3 μm or more and 30 μm or less, and even more preferably 5 μm or more and 20 μm or less, which makes it even more difficult for voids to occur between the alumina particles, and allows the resulting cured product to have a higher breakdown voltage.

[0046] Alumina (b1) has a particle diameter D at which the cumulative frequency is 10% in a volume-based cumulative frequency distribution curve measured using a laser diffraction particle size distribution analyzer. 10 is preferably 0.1 μm or more and 10 μm or less, more preferably 0.2 μm or more and 5 μm or less, and even more preferably 0.3 μm or more and 3 μm or less. 10 When the value is within the above range, the moldability is excellent.

[0047] Alumina (b1) has a particle diameter D at which the cumulative frequency is 90% in a volume-based cumulative frequency distribution curve measured using a laser diffraction particle size distribution analyzer. 90 However, it is preferably 15 μm or more and 55 μm or less, more preferably 20 μm or more and 50 μm or less, and even more preferably 25 μm or more and 45 μm or less. 90 When the value of is within the above range, the dielectric breakdown voltage of the resulting cured product can be further increased and the moldability is also excellent.

[0048] From the viewpoint of the effects of the present invention, the content of alumina (b1) can be preferably 30 parts by mass or more and 90 parts by mass or less, more preferably 40 parts by mass or more and 85 parts by mass or less, and even more preferably 60 parts by mass or more and 80 parts by mass or less, relative to 100% by mass of the entire semiconductor encapsulating resin composition.

[0049] (Other inorganic fillers) As the other inorganic filler that can be contained in the inorganic filler (B), known inorganic fillers used in semiconductor encapsulation resin compositions can be used as long as the effects of the present invention are exhibited. In addition, the other inorganic fillers may be surface-treated.

[0050] Specific examples of other inorganic fillers include silica such as fused silica, crystalline silica, and amorphous silicon dioxide; talc; titanium oxide; silicon nitride; aluminum nitride; etc. These inorganic fillers may be used alone or in combination of two or more.

[0051] From the viewpoint of excellent versatility, the inorganic filler (B) preferably contains silica (b2). Examples of the shape of the silica (b2) include spherical silica and crushed silica.

[0052] In this embodiment, the average particle diameter D at 50% cumulative frequency in the volume-based cumulative frequency distribution curve of silica (b2) measured using a laser diffraction particle size distribution analyzer is 50 can be set to 0.05 μm or more and 20 μm or less, preferably 0.07 μm or more and 15 μm or less. The silica (b2) may contain two or more types of particles having different average particle sizes. For example, when two types of silica (b2-1) and silica (b2-2) with different average particle sizes are contained, silica (b2-1) has a smaller average particle size than silica (b2-2), Average particle size D of silica (b2-1) 50 can be 0.05 μm or more and 3 μm or less, preferably 0.07 μm or more and 2 μm or less, Average particle size D of silica (b2-2) 50 The thickness can be set to 3 μm or more and 20 μm or less, preferably 5 μm or more and 15 μm or less. The silica (b2-1) or silica (b2-2) has the above average particle diameter D 50 The silica particles include one or more types having the formula: The semiconductor encapsulating resin composition of this embodiment contains silica (b2) having the above-mentioned average particle size, and thus has improved flowability, excellent moldability, and excellent filling properties.

[0053] When silica (b2) is contained as the inorganic filler (B), the content of silica (b2) can be set to preferably 3 parts by mass or more and 60 parts by mass or less, more preferably 5 parts by mass or more and 50 parts by mass or less, and even more preferably 10 parts by mass or more and 30 parts by mass or less, per 100 parts by mass of alumina (b1), from the viewpoint of more effectively improving the fluidity and filling property of the semiconductor encapsulating resin composition during molding.

[0054] In this embodiment, the content of the inorganic filler (B) in the semiconductor encapsulating resin composition is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 65% ​​by mass or more, relative to 100% by mass of the entire semiconductor encapsulating resin composition, from the viewpoint of improving the low moisture absorption and low thermal expansion of the encapsulating material formed using the semiconductor encapsulating resin composition and more effectively improving the moisture resistance reliability and reflow resistance of the resulting semiconductor device.

[0055] Furthermore, from the viewpoint of more effectively improving the fluidity and filling property of the semiconductor encapsulating resin composition during molding, the content of the inorganic filler (B) in the semiconductor encapsulating resin composition may be, for example, 97% by mass or less, preferably 95% by mass or less, and more preferably 92% by mass or less, relative to 100% by mass of the entire semiconductor encapsulating resin composition.

[0056] [Carboxylic acid-based dispersants (C) with polycarboxylic acid as the main skeleton] As the carboxylic acid-based dispersant (C) having a polycarboxylic acid as the main skeleton, any conventionally known dispersant can be used as long as it has the structure and can achieve the effects of the present invention. From the viewpoint of the effects of the present invention and moldability, the carboxylic acid-based dispersant (C) is preferably a compound represented by the following general formula (1).

[0057] [ka]

[0058] In general formula (1), R represents a hydrogen atom, a carboxyl group, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylcarboxyl group having 1 to 5 carbon atoms, an alkoxycarboxyl group having 1 to 5 carbon atoms, an alkylalcohol group having 1 to 5 carbon atoms, or an alkoxyalcohol group having 1 to 5 carbon atoms, and multiple Rs may be the same or different.

[0059] R is preferably a carboxyl group, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an alkylcarboxyl group having 1 to 5 carbon atoms.

[0060] X represents an oxygen atom, an alkylene group having 1 to 30 carbon atoms, a divalent chain hydrocarbon group having 1 to 30 carbon atoms and one or more double bonds, or a divalent chain hydrocarbon group having 1 to 30 carbon atoms and one or more triple bonds, and multiple Xs may be the same or different. Examples of the divalent chain hydrocarbon group include alkylene groups.

[0061] X is preferably an oxygen atom, an alkylene group having 1 to 20 carbon atoms, or a divalent chain hydrocarbon group having 1 to 20 carbon atoms and one or more double bonds, and more preferably an oxygen atom, an alkylene group having 1 to 20 carbon atoms, or an alkylene group having 1 to 20 carbon atoms and one double bond. n is an integer of 0 to 20, and m is an integer of 1 to 5.

[0062] The compound represented by general formula (1) is preferably a compound represented by the following general formula (1a) or general formula (1b): The carboxylic acid-based dispersant (C) can contain at least one selected from these.

[0063] [ka]

[0064] In general formula (1a), R, m, and n have the same meanings as in general formula (1). n is preferably an integer of 1 to 20, more preferably 5 to 15, even more preferably 7 to 12, and particularly preferably 10. m is preferably an integer of 1 to 5, more preferably 2 to 4. R is preferably an alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 2 to 8 carbon atoms, and particularly preferably 6.

[0065] [ka]

[0066] In the general formula (1b), Q represents an alkylene group having 1 to 5 carbon atoms, and is preferably an alkylene group having 1 to 3 carbon atoms. 1 is preferably an alkylene group having 1 to 30 carbon atoms, a divalent chain hydrocarbon group having 1 to 30 carbon atoms and having one or more double bonds, or a divalent chain hydrocarbon group having 1 to 30 carbon atoms and having one or more triple bonds, more preferably an alkylene group having 10 to 30 carbon atoms, a divalent chain hydrocarbon group having 10 to 30 carbon atoms and having one or more double bonds, or a divalent chain hydrocarbon group having 10 to 30 carbon atoms and having one or more triple bonds, and particularly preferably a divalent chain hydrocarbon group having 10 to 30 carbon atoms and having one or more double bonds.

[0067] The acid value of the carboxylic acid dispersant (C) is 5 to 500 mgKOH / g, preferably 10 to 350 mgKOH / g, and more preferably 15 to 100 mgKOH / g. When the acid value is within the above range, the alumina (b1) surface is more excellent in wettability, and the flowability and moldability are also excellent.

[0068] The content of the carboxylic acid-based dispersant (C) can be set to preferably 0.05 parts by mass or more and 5 parts by mass or less, more preferably 0.08 parts by mass or more and 3 parts by mass or less, and even more preferably 0.1 parts by mass or more and 2 parts by mass or less, relative to 100 parts by mass of the alumina (b1).

[0069] Within the above range, the wettability of the surface of the alumina (b1) having the above average particle size can be further improved, and the resin can be easily filled between the alumina (b1), suppressing the generation of voids, thereby increasing the breakdown voltage of the resulting cured product. Furthermore, the dispersibility of the alumina (b1) in the semiconductor encapsulation resin composition is excellent, and the flowability of the resin composition is improved, resulting in even more excellent moldability.

[0070] From the viewpoint of the effects of the present invention and moldability, the content of the carboxylic acid-based dispersant (C) can be preferably 0.01 mass % or more and 4 mass % or less, more preferably 0.05 mass parts or more and 3 mass parts or less, and even more preferably 0.1 mass parts or more and 2 mass parts or less, relative to 100 mass % of the semiconductor encapsulating resin composition.

[0071] Examples of the compound represented by general formula (1) which is the carboxylic acid-based dispersant (C) include Hypermer KD-4 (mass average molecular weight: 1700, acid value: 33 mg KOH / g), Hypermer KD-9 (mass average molecular weight: 760, acid value: 74 mg KOH / g), Hypermer KD-12 (mass average molecular weight: 490, acid value: 111 mg KOH / g), and Hypermer KD-16 (mass average molecular weight: 370, acid value: 299 mg KOH / g), all of which are manufactured by CRODA.

[0072] [Hardening agent (D)] As the curing agent (D), any known curing agent used in a semiconductor encapsulating resin composition can be used as long as the effects of the present invention are achieved. In this embodiment, the curing agent (D) preferably contains a phenolic resin-based curing agent. As the phenolic resin-based curing agent, any monomer, oligomer, or polymer having two or more phenolic hydroxyl groups in one molecule can be used, and the molecular weight and molecular structure thereof are not particularly limited.

[0073] The phenolic resin-based curing agent preferably contains a skeleton selected from the group consisting of a novolac skeleton and a biphenyl skeleton. When the phenolic curing agent contains any of these skeletons, the durability of the cured product can be particularly improved. Specifically, the "biphenyl skeleton" is a structure in which two benzene rings are linked by a single bond, as in the general formula (BP) in the explanation of the epoxy resin mentioned above.

[0074] Specific examples of phenolic curing agents having a biphenyl skeleton include biphenylaralkyl phenolic resins having a structure in which the glycidyl group in the general formula (BP1) in the description of the epoxy resin above is replaced with a hydrogen atom. Specific examples of phenolic curing agents having a novolac skeleton include those having a structural unit represented by the following general formula (N).

[0075] [ka]

[0076] In general formula (N), R 4 represents a monovalent substituent, u is an integer of 0 to 3. R 4 Specific examples of the monovalent substituent include R in general formula (BP): a and R b Examples of the monovalent substituent include those described above. u is preferably 0 to 2, more preferably 0 to 1, and even more preferably 0.

[0077] The phenolic resin-based curing agent used as the curing agent (D) is preferably at least one selected from novolac-type phenolic resins, biphenylaralkyl-type phenolic resins, and Zylok-type phenolic resins, and more preferably a biphenylaralkyl-type phenolic resin.

[0078] The content of the curing agent (D) in the semiconductor encapsulating resin composition can be preferably 1% by weight or more, more preferably 1.5% by weight or more, and even more preferably 2% by weight or more, based on 100% by weight of the entire semiconductor encapsulating resin composition. By setting the content of the curing agent to be equal to or more than the above lower limit, the storage stability at room temperature is improved, and excellent fluidity is achieved during molding, thereby improving filling properties and moldability.

[0079] On the other hand, the content of the curing agent (D) in the semiconductor encapsulating resin composition can be preferably 15% by weight or less, more preferably 10% by weight or less, and even more preferably 5% by weight or less, based on 100% by weight of the entire semiconductor encapsulating resin composition. By setting the content of the curing agent (D) to the above upper limit or less, it is possible to improve moisture resistance reliability and reflow resistance.

[0080] [Curing accelerator (E)] The semiconductor encapsulation resin composition of this embodiment may contain a curing accelerator (E), which may also be called a curing catalyst.

[0081] The curing accelerator (E) is not particularly limited, and examples thereof include imidazoles, salts of triphenylphosphine or tetraphenylphosphine, amine compounds such as diazabicycloundecene and salts thereof, and the like. However, salts of tetraphenylphosphine such as tetraphenylphosphonium tetrakis(1-naphthoyloxy)borate, tetraphenylphosphonium 4,4'-sulfonyldiphenolate, tetraphenylphosphonium bis(naphthalene-2,3-dioxy)phenylsilicate, tetraphenylphosphonium trihydrogenbis(X,X'-methylenediphenolate), and tetraphenylphosphonium 2,3-dihydroxynaphthalate are preferably used.

[0082] The content of the curing accelerator (E) in the semiconductor encapsulating resin composition can be set to preferably 0.01 to 1 mass %, more preferably 0.05 to 0.8 mass %, relative to 100 mass % of the entire semiconductor encapsulating resin composition.

[0083] [Other ingredients] The semiconductor encapsulation resin composition of the present embodiment may contain components other than the above-mentioned components, and for example, one or more of various additives such as a coupling agent, a mold release agent, an ion scavenger, a flame retardant, a colorant, an antioxidant, a stress reducing agent, and an adhesion aid may be appropriately blended.

[0084] (Method of manufacturing semiconductor encapsulating resin composition) The method for producing the semiconductor encapsulation resin composition of this embodiment is not particularly limited. For example, the above-mentioned components are mixed by a known means, melt-kneaded in a kneading machine such as a roll, a kneader or an extruder, cooled, and then pulverized to obtain the desired composition. If necessary, the powder may be compressed into tablets, or if necessary, the powder may be formed into a sheet by, for example, vacuum lamination or compression molding. If necessary, the degree of dispersion, flowability, etc. of the obtained semiconductor encapsulating resin composition may be adjusted.

[0085] (Properties of semiconductor encapsulation resin composition) The semiconductor encapsulating resin composition of this embodiment is in the form of, for example, particles or a sheet. Specific examples of particulate semiconductor encapsulation resin compositions include those in the form of granules or tablets. When the semiconductor encapsulating resin composition is in the form of a tablet, the semiconductor encapsulating resin composition can be molded, for example, by transfer molding.

[0086] When the semiconductor encapsulating resin composition is in the form of powder or granules, the semiconductor encapsulating resin composition can be molded, for example, by compression molding. Here, the semiconductor encapsulating resin composition being in the form of powder or granules.

[0087] <Semiconductor device> The semiconductor encapsulation resin composition of the present embodiment can be used as an encapsulant for a semiconductor device (insulated gate driver). The semiconductor device can be surface-mounted on a wiring board of an inverter device of an electric vehicle or a hybrid vehicle, for example.

[0088] As shown in FIG. 1, the insulated gate driver 30 includes a lead frame 34 including a first die pad (input terminal), a lead frame 40 including a second die pad (high-voltage output terminal) having a higher voltage than the first die pad, a first semiconductor element 36 and a transformer chip 38 mounted on the first die pad, a second semiconductor element 42 mounted on the second die pad, and an encapsulant 46 made of a cured product of the semiconductor encapsulation resin composition of this embodiment that covers the first and second die pads, the first semiconductor element 36, and the second semiconductor element 42.

[0089] The lead frame 34 including the first die pad (input side terminal) is bonded to the wiring board of the inverter device, thereby electrically connecting the semiconductor device 30 to the wiring board. The lead frame 40 including the second die pad (high voltage output side terminal) is bonded to the wiring board of the inverter device in the same manner as the first die pad 34, thereby electrically connecting the semiconductor device 30 to the wiring board.

[0090] The wires 44 electrically connect the lead frame 34 and the first semiconductor element 36, the first semiconductor element 36 and the transformer chip 38, the transformer chip 38 and the second semiconductor element 42, and the second semiconductor element 42 and the lead frame 40. The wires 44 can be made of a metal including, for example, Au, Cu, or Al.

[0091] The first semiconductor element 36 has a control unit, which converts signals input from an ECU or the like into control signals and sends them to the transformer chip 38 via wires 44. The transformer chip 38 transmits electrical signals from the control unit of the first semiconductor element 36 to the second semiconductor element 42 via wires 44.

[0092] The second semiconductor element 42 includes a high-voltage driving section, and drives the switching elements (such as IGBTs and MOSFETs) of the inverter device based on the electrical signals transmitted from the transformer chip 38 via wires 44.

[0093] The encapsulant 46 is made of a cured product of the semiconductor encapsulation resin composition of this embodiment, and therefore has a high breakdown voltage and a long insulation life, resulting in excellent product reliability for the semiconductor device (insulated gate driver).Furthermore, it has excellent insulation properties in the voltage difference between the high-voltage side and the low-voltage side. Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various configurations other than those described above can be adopted as long as they do not impair the effects of the present invention. [Example]

[0094] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0095] <Comparative Example 1, Examples 1 and 2 (Production of Semiconductor Encapsulating Resin Composition)> The components listed in Table 1 were mixed in the ratios shown to obtain a mixture. The mixing was carried out at room temperature using a Henschel mixer. The mixture was then roll-kneaded at 70 to 100°C to obtain a kneaded product. The kneaded product was cooled and then pulverized to obtain a resin composition for semiconductor encapsulation. The components listed in Table 1 are as follows:

[0096] (inorganic filler) Alumina particles 1: Fused spherical alumina (DAB-45SI, manufactured by Denka Co., Ltd., D 10 :1.3μm,D 50 :9.5μm, D 90 : 38 μm, mode diameter: 12 μm) Silica particles 1: fused spherical silica (FB-105, manufactured by Denka Co., Ltd., D 50 :10.6μm) Silica particles 2: Fused spherical silica (SC-2500-SQ, manufactured by Admatechs Co., Ltd., D 50 :0.6μm) Silica particles 3: dry silica (Reolosil CP-102, manufactured by Tokuyama Corporation, D 50 =0.12μm)

[0097] (coloring agent) Colorant 1: Carbon black (ERS-2001, manufactured by Tokai Carbon Co., Ltd.)

[0098] (coupling agent) Silane coupling agent 1: N-phenyl-3-aminopropyltrimethoxysilane (CF-4083, manufactured by Toray Dow Corning Co., Ltd.)

[0099] (epoxy resin) Epoxy resin 1: Biphenyl type epoxy resin (Mitsubishi Chemical Corporation, YX-4000HK) (hardening agent) Hardener 1: Novolac phenol compound (Sumitomo Bakelite Co., Ltd., PR-51714) Curing agent 2: Biphenylene skeleton-containing phenol aralkyl resin (MEH-7851H, manufactured by Meiwa Kasei Co., Ltd.)

[0100] (curing catalyst) Curing catalyst 1: Tetraphenylphosphonium tetrakis(1-naphthoyloxy)borate Curing catalyst 2: Tetraphenylphosphonium 4,4-sulfonyldiphenolate

[0101] (mold release agent) Release agent 1: Oxidized polyethylene wax (Ricowax PED191, Clariant Japan) Release agent 2: Carnauba wax (C-WAX, manufactured by Toa Kasei Co., Ltd.)

[0102] (ion scavenger) Ion scavenger 1: Magnesium aluminum hydroxide carbonate hydrate (Kyowa Chemical Industry Co., Ltd., DHT-4H)

[0103] (carboxylic acid dispersant) Carboxylic acid dispersant 1: Polycondensate of 12-hydroxystearic acid (Hypermer KD-9, Croda Japan, mass average molecular weight: 760, acid value: 74 mg KOH / g)

[0104] (additives) Additive 1: 4,6-diamino-1,3,5-triazine-2-ethanol (Shikoku Chemicals Corporation, VD-HT) (low stress agent) Low-stress agent 1: Epoxy-polyether modified silicone oil (FZ-3730, Toray Dow) Low-stress agent 2: Carboxyl-terminated butadiene-acrylonitrile copolymer, HYCAR CTBN 1008-SP, manufactured by PTI Japan

[0105] The physical properties were measured by the following methods. (Spiral Flow) Using a low-pressure transfer molding machine (KTS-15, manufactured by Kotaki Seiki Co., Ltd.), the semiconductor encapsulation resin compositions obtained in the Examples and Comparative Examples were injected into a spiral flow measurement mold conforming to ANSI / ASTM D 3123-72, and the flow length was measured under the following conditions: mold temperature 175°C, injection pressure 6.9 MPa, and pressure dwell time 120 seconds. Spiral flow is a parameter of fluidity, and the larger the value, the better the fluidity. The unit is cm.

[0106] (thermal conductivity) The semiconductor encapsulation resin compositions obtained in the Examples and Comparative Examples were cured by heating at 175°C for 120 seconds to obtain cured sheets (10 mm x 10 mm x 1.0 mm thick). The thermal conductivity (W / (m·k)) of the cured sheets in the thickness direction was then measured at room temperature using a laser flash method.

[0107] (Dielectric breakdown strength) The semiconductor encapsulation resin compositions obtained in the examples or comparative examples were cured under the conditions of a molding temperature of 175°C and a curing time of 90 seconds to prepare disk-shaped samples with a diameter of 100 mm and a thickness of 2 mm. Next, as shown in Figure 2, the sample 16 was sandwiched between an upper brass electrode 18 (φ25 mm × 25 mm, edge 3.2 mm R) and a lower brass electrode 20 (φ25 mm × 25 mm, edge 3.2 mm R) in an oil bath 14 containing 21°C silicone oil as insulating oil 12, and a lead wire 22 was connected to the upper electrode 18. Next, the voltage was increased at a rate of 1 kV / min (short-term test), and the breakdown voltage was measured. The breakdown strength was calculated by dividing the obtained breakdown voltage by the sample thickness. The sample thickness was measured using a micrometer before the test. The thickness at one measurement point was used as the sample thickness.

[0108] [Table 1]

[0109] As shown in Table 1, Examples 1 and 2, which relate to the semiconductor encapsulation resin compositions of the present invention, have high spiral flow values ​​and excellent fluidity, demonstrating excellent moldability. Furthermore, it was revealed that the cured products made from the semiconductor encapsulation resin compositions of Examples 1 and 2 have excellent thermal conductivity, high breakdown voltage, long insulation life, and can provide encapsulants with excellent product reliability. [Explanation of symbols]

[0110] 30 Isolated Gate Drivers 34 Lead frame including first die pad (input terminal) 36 First semiconductor element 38 Transformer Chip 40 Lead frame including second die pad (high voltage output terminal) 42 second semiconductor element 44 wires 46 Encapsulating material

Claims

1. (A) an epoxy resin; (B) an inorganic filler; (C) a carboxylic acid-based dispersant having a polycarboxylic acid as a main skeleton, The resin composition for semiconductor encapsulation, wherein the inorganic filler (B) contains alumina (b1) having an average particle diameter of 5 μm or more and 45 μm or less.

2. 2. The resin composition for semiconductor encapsulation according to claim 1, comprising the carboxylic acid-based dispersant (C) in an amount of 0.05 parts by mass or more and 5 parts by mass or less per 100 parts by mass of the alumina (b1).

3. The semiconductor encapsulating resin composition according to claim 1 , wherein the inorganic filler (B) comprises silica (b2).

4. 2. The semiconductor encapsulating resin composition according to claim 1, wherein the carboxylic acid-based dispersant (C) is a compound represented by the following general formula (1): 【Chemical 1】 (In general formula (1), R represents a hydrogen atom, a carboxyl group, a hydroxyl group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylcarboxyl group having 1 to 5 carbon atoms, an alkoxycarboxyl group having 1 to 5 carbon atoms, an alkylalcohol group having 1 to 5 carbon atoms, or an alkoxyalcohol group having 1 to 5 carbon atoms, and multiple Rs may be the same or different. X represents an oxygen atom, an alkylene group having 1 to 30 carbon atoms, a divalent chain hydrocarbon group having 1 to 30 carbon atoms and having one or more double bonds, or a divalent chain hydrocarbon group having 1 to 30 carbon atoms and having one or more triple bonds, and multiple Xs may be the same or different. n represents an integer of 0 to 20, and m represents an integer of 1 to 5.)

5. The semiconductor encapsulating resin composition according to claim 1 , further comprising a curing agent (D).

6. The semiconductor encapsulating resin composition according to claim 1 , further comprising a curing accelerator (E).

7. a semiconductor element mounted on a substrate; an encapsulant for encapsulating the semiconductor element, the encapsulant comprising a cured product of the semiconductor encapsulation resin composition according to any one of claims 1 to 6; A semiconductor device comprising:

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