JP2023146639A - Sealing resin composition - Google Patents

Abstract

To provide a sealing resin composition which is excellent in the reliability and heat resistance of a cured product thereof.SOLUTION: A sealing resin composition contains component (A): an epoxy resin, component (B): a phenol resin curing agent, and component (C): a maleimide compound. At least one of the component (A) and the component (B) is a polyaromatic ring resin (MAR). In a chart of tanδ of a cured product of the sealing resin composition when measured in a measurement temperature range of 0-400°C at a rate of temperature increase of 5°C/min by dynamic mechanical analysis (DMA), a peak does not exist in the temperature region of 200-300°C while a peak exists in the temperature region of 300-400°C.SELECTED DRAWING: None

Description

The present invention relates to a sealing resin composition.

2. Description of the Related Art There are techniques described in Patent Documents 1 and 2 as techniques related to a sealing material used for sealing a semiconductor element.
Patent Document 1 (Japanese Unexamined Patent Publication No. 2020-26509) describes a resin composition obtained by melting a resin mixture containing a polymaleimide compound having a specific structure and number of repeating units and a phenol resin. (Claim 1) According to the same document, by using the above resin mixture, a resin composition with good solubility in low boiling point solvents can be obtained regardless of the melting temperature, and therefore, the range of melting temperatures allowed in melt mixing is wide and productivity is improved. It is said that a resin mixture having good solubility in a low boiling point solvent can be provided (paragraph 0013).

Patent Document 2 (International Publication No. 2019/208614) describes a resin composition, laminate, and resin composition layer that has excellent flux activity, flexibility, and storage stability and is suitable for underfill materials. As a technology for providing a semiconductor wafer with a resin composition layer, a semiconductor mounting substrate with a resin composition layer, and a semiconductor device (paragraph 0012), a resin composition containing a compound having a phenolic hydroxyl group, a metal ion scavenger, and a radically polymerizable compound It describes a product (Claim 1).

Japanese Patent Application Publication No. 2020-26509 International Publication No. 2019/208614

However, as a result of studies conducted by the present inventors, when the resin compositions described in Patent Documents 1 and 2 are used as encapsulants for electronic devices, improvements can be made in terms of achieving both reliability and heat resistance at a high level. It became clear that there was room for

The present invention provides a sealing resin composition that provides a cured product with excellent reliability and heat resistance.

According to the invention,
(A) epoxy resin,
(B) a phenolic resin curing agent; and (C) a maleimide compound.
At least one of the components (A) and (B) is a polyaromatic resin (MAR),
In the chart of the loss tangent (tan δ) of the cured product of the sealing resin composition measured by dynamic mechanical analysis (DMA) at a measurement temperature range of 0 ° C. to 400 ° C. and a temperature increase rate of 5 ° C./min, A sealing resin composition is provided that has no peak in the temperature range of 200 to 300°C and has a peak in the temperature range of 300 to 400°C.

Further, according to the present invention, it is also possible to obtain an electronic device in which an electronic component such as a semiconductor element is sealed with the sealing resin composition of the present invention described above.

According to the present invention, it is possible to provide a sealing resin composition that exhibits excellent reliability and heat resistance of a cured product.

FIG. 1 is a cross-sectional view showing the configuration of a semiconductor device in an embodiment. FIG. 1 is a cross-sectional view showing the configuration of a semiconductor device in an embodiment. FIG. 2 is a diagram showing the relationship between temperature and tan δ measured by DMA measurement of a cured product of a resin composition.

Embodiments will be described below with reference to the drawings. Note that in all the drawings, similar components are denoted by the same reference numerals, and descriptions thereof will be omitted as appropriate. Moreover, each component can be used alone or in combination of two or more.

In this embodiment, the sealing resin composition (hereinafter also simply referred to as "resin composition") includes component (A): epoxy resin, component (B): phenolic resin curing agent, and component (C): Contains a maleimide compound, at least one of components (A) and (B) is a polyaromatic resin (MAR), and dynamic mechanical analysis (DMA) shows that the temperature range is 0°C to 400°C and the heating rate is In the chart of the loss tangent (tan δ) of the cured product of the sealing resin composition measured at a temperature increase of 5°C/min, there is no peak in the temperature range of 200 to 300°C, and there is no peak in the temperature range of 300 to 400°C. A peak exists in the temperature range.

Here, specifically, the cured product used for the measurement of tan δ is cured using a transfer molding machine (for example, "KTS-15" manufactured by Kotaki Seiki Co., Ltd.) at a mold temperature of 175 ° C. and an injection pressure of 6.9 MPa. The resin composition for sealing was produced by injection molding in 120 seconds to obtain a cured product measuring 10 mm x 4 mm x 4 mm. After curing at 200° C. for 4 hours, it was used as a test piece.
Furthermore, tan δ is measured using a DMA measuring device (manufactured by Seiko Instruments, Inc., for example) under the condition of 10 Hz in accordance with JIS K 6911.

The present inventor studied the structure of the resin composition from the viewpoint of achieving both reliability and heat resistance of the cured product of the sealing resin composition at a high level. As a result, the resin composition was configured to contain specific components (A) to (C), and in the tan δ measurement chart of the cured product of the resin composition, there was no peak in the temperature range of 200 to 300°C, and 300 It has been found that by creating a structure in which a peak exists in the temperature range of ~400°C, a resin composition having excellent reliability and heat resistance of a cured product can be obtained.

It is not necessarily clear why a cured product with excellent reliability and heat resistance can be obtained when the resin composition contains the above-mentioned components and the tan δ measurement chart of the cured product has the above-mentioned configuration. The following points are inferred. In other words, the temperature at which the cross-linked polymer changes from a glass state to a rubber state increases due to curing, which is thought to improve heat resistance, and also allows stable performance to be maintained even at high junction temperatures in semiconductor chips, for example. It is assumed that the reliability will also be excellent.
In addition, the above characteristics can be obtained by appropriately adjusting the types and amounts of each component constituting the resin composition.More specifically, the characteristics of components (A) and (B) in the resin composition can be This can be achieved by controlling the equivalence ratio of and the blending amount of component (C).

The glass transition temperature Tg1 of the cured product measured by DMA and the glass of the cured product measured by thermomechanical analysis (TMA) at a temperature range of 0°C to 320°C and a temperature increase rate of 5°C/min. The difference from the transition temperature Tg2 (Tg1-Tg2) is preferably 50°C or higher, more preferably 60°C or higher, and even more preferably 70°C or higher, from the viewpoint of improving heat resistance.
Further, from the viewpoint of reducing brittleness, the above difference (Tg1-Tg2) is preferably 150°C or less, more preferably 130°C or less, and still more preferably 110°C or less.

Here, Tg1 by DMA can be determined from the peak value of tan δ from the tan δ measurement chart of the cured product described above.
Moreover, the measurement of Tg2 by TMA is specifically performed by the following method.
That is, the thermosetting resin composition is compression molded under conditions of a molding temperature of 175° C. for 3 minutes and a post mode cure of 175° C. for 4 hours to obtain a cured product. The glass transition temperature of the cured product is measured using a TMA (for example, TMA6100 manufactured by Hitachi High-Technologies) at a heating rate of 10° C./min.

The ratio of the average linear expansion coefficient α2 in the range of 270°C to 300°C to the average linear expansion coefficient α1 in the range of 40°C to 80°C of the cured product of the resin composition measured by the above TMA (α2/α1) is preferably 7 or less, preferably 5 or less, more preferably 4 or less, from the viewpoint of heat cycle characteristics. Further, the linear expansion coefficient ratio (α2/α1) is, for example, 1.1 or more, and may be, for example, 3 or more.

The gel time of the resin composition at 175°C is preferably 5 seconds or more, more preferably 10 seconds or more, and even more preferably 15 seconds or more, from the viewpoint of improving the balance between fillability and moldability of the resin composition. Also, preferably it is 100 seconds or less, more preferably 50 seconds or less, still more preferably 30 seconds or less.
Here, the gel time measurement can be performed, for example, by measuring the time from when the resin composition is placed on a hot plate heated to 175°C until it becomes tack-free.

Next, the constituent components of the sealing resin composition of this embodiment will be explained.
(Component (A))
Component (A) is an epoxy resin.
From the viewpoint of improving the reliability and heat resistance of the cured product of the resin composition, component (A) preferably contains a multi-aromatic resin (MAR), and is more preferably MAR.
In addition, from the viewpoint of improving the reliability and heat resistance of the cured product of the resin composition, component (A) is preferably a bifunctional or higher functional epoxy resin, more preferably a trifunctional or higher functional epoxy resin, and Preferred is an epoxy resin having four or less functionalities.

Specific examples of the polyvalent MAR type epoxy resin include polyvalent MAR containing a biphenyl skeleton and polyvalent MAR containing a naphthalene skeleton.
Examples of the biphenyl skeleton-containing polyvalent MAR include those shown in the following general formula (1). Furthermore, examples of polyvalent MARs containing naphthalene skeletons include those shown in the following formula (2).

(In the above general formula (1), m1, m2 and m3 are each independently 1 or 2, and n1 is a number from 1 to 10.)

From the viewpoint of improving the heat resistance of the cured product of the resin composition, component (A) is preferably an epoxy resin having a naphthalene skeleton, and more preferably contains a difunctional to tetrafunctional epoxy resin containing a naphthalene skeleton. .

The epoxy equivalent of component (A) in the resin composition, that is, the total epoxy resin, is preferably 150 g/eq or more, more preferably 180 g/eq or more, from the viewpoint of improving the glass transition temperature, which is an important element of heat resistance. and more preferably 200 g/eq or more.
Further, from the viewpoint of high glass transition temperature stability, the epoxy equivalent is preferably 250 g/eq or less, more preferably 230 g/eq or less, and even more preferably 220 g/eq or less.

Here, the epoxy equivalent of component (A) can be specifically measured according to JIS K7236, and is the mass of the resin containing 1 equivalent of epoxy group. Further, in the present embodiment, when a mixture of multiple types of epoxy resins is used, the epoxy equivalent is the number of equivalents after mixing the multiple types of epoxy resins.

The content of component (A) in the resin composition is preferably 5% by mass based on the entire resin composition from the viewpoint of achieving excellent fluidity and improving filling properties and adhesion during molding. The content is more preferably 7% by mass or more, and even more preferably 8% by mass or more.
Furthermore, from the viewpoint of improving high-temperature reliability and reflow resistance of semiconductor devices obtained using the resin composition, the content of component (A) in the resin composition is preferably set relative to the entire resin composition. The content is 15% by mass or less, more preferably 14% by mass or less, even more preferably 13% by mass or less.

(Component (B))
Component (B) is a phenolic resin.
From the viewpoint of improving the reliability and heat resistance of the cured product of the resin composition, component (B) preferably contains a multi-aromatic resin (MAR), and is more preferably MAR.
In addition, from the viewpoint of improving the reliability and heat resistance of the cured product of the resin composition, component (B) is preferably a bifunctional or higher functional phenolic resin, more preferably a trifunctional or higher functional phenolic resin, and Preferred is a phenol resin having four or less functionalities.

Specific examples of the polyvalent MAR type phenolic resin include biphenyl skeleton-containing polyvalent MAR and naphthalene skeleton-containing polyvalent MAR.
Examples of the biphenyl skeleton-containing polyvalent MAR include those shown in the following general formula (3).

(In the above general formula (3), n2 is a number from 1 to 10.)

The equivalent ratio (EP/OH) of the number of epoxy groups in component (A) to the number of phenolic hydroxyl groups OH in component (B) in the resin composition (EP/OH) is an important factor for maximizing crosslinking density and improving heat resistance. From the viewpoint of improving the glass transition temperature, which is a factor, it is preferably 1.5 or more, more preferably 2.0 or more, and still more preferably 2.2 or more.
Further, from the viewpoint of high glass transition temperature stability, the equivalence ratio (EP/OH) is preferably 10 or less, more preferably 8.0 or less, and even more preferably 6.0 or less.

Here, the phenolic hydroxyl equivalent of component (B) can be determined, for example, by measurement. Specifically, by reacting a monoepoxy resin with a known epoxy equivalent, such as phenyl glycidyl ether, with a curing agent with an unknown phenolic hydroxyl equivalent, and measuring the amount of monoepoxy resin consumed, the curing agent used can be determined. The phenolic hydroxyl group equivalent of can be determined.

The content of component (B) in the resin composition is preferably 0.5 with respect to the entire resin composition from the viewpoint of achieving excellent fluidity and improving filling properties and adhesion during molding. It is at least 1.0% by mass, more preferably at least 1.5% by mass.
Furthermore, from the viewpoint of improving high-temperature reliability and reflow resistance of semiconductor devices obtained using the resin composition, the content of component (B) in the resin composition is preferably set relative to the entire resin composition. The content is 10% by mass or less, more preferably 7% by mass or less, even more preferably 5% by mass or less.

In this embodiment, at least one of components (A) and (B) is MAR. From the viewpoint of improving the heat resistance of the cured product, preferably components (A) and (B) are both MARs, and more preferably components (A) and (B) are both trifunctional or higher functional MARs.

(Component (C))
Component (C) is a maleimide compound, preferably a compound having two or more maleimide groups.
Component (C) preferably contains a compound represented by the following general formula (4) from the viewpoint of improving the heat resistance of the cured product.

In the general formula (4), each of the plurality of R ₂ 's is independently a hydrogen atom or a substituted or unsubstituted hydrocarbon group having 1 or more and 4 or less carbon atoms, preferably all of them are hydrogen atoms. n3 is an average value, and is a number from 0 to 10, preferably from 0 to 5.

The softening point of component (C) is preferably 65°C or higher, more preferably 70°C or higher, and still more preferably 75°C or higher, from the viewpoint of improving handling properties during production of the resin composition.
In addition, from the viewpoint of making kneading easier during the preparation of the resin composition, the softening point of component (C) is preferably 170°C or lower, more preferably 150°C or lower, and even more preferably 120°C or lower. .

The content of component (C) ((C)/((A)+(B)+(C))) with respect to 100 parts by mass of the total content of components (A) to (C) in the resin composition is: From the viewpoint of improving the glass transition temperature, the amount is preferably 10 parts by mass or more, more preferably 15 parts by mass or more, and still more preferably 18 parts by mass or more.
Further, from the viewpoint of suppressing the cured product from becoming too hard and brittle, the above ((C)/((A)+(B)+(C))) is preferably 40 parts by mass or less, more preferably is 35 parts by mass or less, more preferably 32 parts by mass or less.

The mass ratio ((B)/((A)+(C))) of the content of component (B) to the total content of components (A) and (C) in the resin composition is the From this point of view, it is preferably 0.30 or less, more preferably 0.24 or less, even more preferably 0.20 or less. Further, the mass ratio ((B)/((A)+(C))) may be, for example, 0.05 or more.

Furthermore, the resin composition may further contain components other than components (A) to (C).

(Component (D))
The resin composition may further contain a curing accelerator, and preferably further contains component (D): an imidazole compound. Thereby, the reliability and heat resistance of the cured product of the resin composition can be improved even more stably.
As component (D), for example, 2-methylimidazole, 2-ethyl-4-methylimidazole (EMI24), 2-phenyl-4-methylimidazole (2P4MZ), 2-phenylimidazole (2PZ), 2-phenyl-4 -One or more compounds selected from the group consisting of methyl-5-hydroxyimidazole (2P4MHZ), 1-benzyl-2-phenylimidazole (1B2PZ), and 2-phenyl-4,5-dihydroxymethylimidazole (2PHZ) can be mentioned.
From the viewpoint of improving the balance between curing speed and storage stability, component (D) is preferably at least one of 2-phenylimidazole and 2-phenyl-4,5-dihydroxymethylimidazole, more preferably 2-phenylimidazole. It is.

From the viewpoint of effectively improving the curability of the resin composition, the content of component (D) in the resin composition is preferably 0.01% by mass or more based on the entire resin composition, and more preferably The content is 0.05% by mass or more, more preferably 0.1% by mass or more, even more preferably 0.2% by mass or more.
Furthermore, from the viewpoint of improving the handling properties of the resin composition, the content of component (D) in the resin composition is preferably 5% by mass or less, more preferably 3% by mass or less based on the entire resin composition. , more preferably 1% by mass or less, even more preferably 0.5% by mass or less.

(Inorganic filler)
Specifically, the resin composition further includes an inorganic filler.
Examples of inorganic fillers include silica, alumina, kaolin, talc, clay, mica, rock wool, wollastonite, glass powder, glass flakes, glass beads, glass fiber, silicon carbide, silicon nitride, aluminum nitride, and carbon black. , graphite, titanium dioxide, calcium carbonate, calcium sulfate, barium carbonate, magnesium carbonate, magnesium sulfate, barium sulfate, cellulose, aramid, and wood.

The average particle size of the inorganic filler is not limited, but is typically 1 to 100 μm, preferably 1 to 50 μm, and more preferably 1 to 30 μm. By having an appropriate average particle size, it is possible to improve the filling property around the semiconductor element within the mold cavity.
Here, the volume-based particle size distribution of the inorganic filler can be measured using a commercially available laser particle size analyzer (for example, SALD-7000 manufactured by Shimadzu Corporation).

The content of the inorganic filler in the resin composition is preferably 70% by mass or more, more preferably 75% by mass or more based on the entire resin composition, from the viewpoint of improving the reliability and heat resistance of the cured product of the resin composition. It is at least 78% by mass, more preferably at least 78% by mass.
In addition, from the viewpoint of more effectively improving fluidity and filling properties during molding of the resin composition, the content of the inorganic filler in the resin composition is preferably 90% by mass or less based on the entire resin composition. It is more preferably 86% by mass or less, still more preferably 83% by mass or less.

(Silane coupling agent)
By configuring the resin composition to further include a silane coupling agent, it is possible to further improve the adhesion between the cured product of the resin composition and an adjacent member.
As the silane coupling agent, various silane compounds such as epoxysilane, mercaptosilane, aminosilane, alkylsilane, ureidosilane, vinylsilane, and methacrylsilane can be used.
More specifically, the silane coupling agent includes vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, γ-methacryloxypropyltrimethoxysilane, β-(3,4 -Epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ -Methacryloxypropyltriethoxysilane, vinyltriacetoxysilane, phenylaminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-anilinopropyltrimethoxysilane, γ-anilinopropylmethyldimethoxysilane, γ-[bis (β-hydroxyethyl)]aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropyltriethoxysilane, N-β -(Aminoethyl)-γ-aminopropylmethyldimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-(β-aminoethyl)aminopropyldimethoxymethylsilane, N-(trimethoxysilylpropyl)ethylenediamine, N-(dimethoxymethylsilylisopropyl)ethylenediamine, methyltrimethoxysilane, dimethyldimethoxysilane, methyltriethoxysilane, N-β-(N-vinylbenzylaminoethyl)-γ-aminopropyltrimethoxysilane, γ-chloropropyltri Methoxysilane, hexamethyldisilane, vinyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine. Examples include hydrolysates.

The content of the silane coupling agent in the resin composition is preferably 0.05% by mass or more based on the entire resin composition from the viewpoint of improving the dispersibility of components in the resin composition, such as inorganic fillers. , more preferably 0.1% by mass or more, still more preferably 0.2% by mass or more.
In addition, from the viewpoint of improving the fluidity and moldability of the resin composition, the content of the silane coupling agent in the resin composition is preferably 2% by mass or less, more preferably 1% by mass or less, and 0.5% by mass or less. % by mass or less.

(Additive)
The resin composition further contains, if necessary, an ion scavenger such as inorganic ion exchangers such as hydrotalcites and polyvalent metal acid salts; natural wax such as carnauba wax, synthetic wax, zinc stearate, etc. Release agents such as higher fatty acids and their metal salts or paraffin; Coloring agents such as carbon black and red iron; Flame retardants such as aluminum hydroxide, magnesium hydroxide, zinc borate, zinc molybdate, and phosphazene; Antioxidants; Additives such as low stress agents such as silicone oil and silicone rubber may be appropriately blended.
The content of each additive in the resin composition can be, for example, about 0.01 to 1% by mass based on the entire resin composition.

Next, a method for manufacturing the sealing resin composition will be explained.
The resin composition can be obtained by mixing components (A) to (C) and other components as appropriate by a method commonly used in the field. Further, after mixing, the mixture may be further melt-kneaded using a kneader such as a roll, a kneader, or an extruder, and may be pulverized after cooling. Furthermore, these can also be compressed into tablets and used as a resin composition. Thereby, a granular or tablet-shaped sealing resin composition can be obtained.
By forming such a composition into a tablet, it becomes easy to perform sealing molding using known molding methods such as transfer molding, injection molding, and compression molding.

Here, it is assumed that the resin composition has no peak in the temperature range of 200 to 300°C and a peak in the temperature range of 300 to 400°C in the tan δ measurement chart in the DMA measurement of the cured product. In order to achieve this, it is important to appropriately adjust the types and amounts of components to be blended into the resin composition. More specifically, at least one of the components (A) and (B) is of the MAR type, and the equivalent ratio (EP/OH) and the component relative to the total of components (A) to (C) in the resin composition. By controlling the blending amount of (C), it is possible to stably obtain a resin composition exhibiting the above-mentioned tan δ measurement chart.

The resin composition obtained in this embodiment has excellent reliability and heat resistance as a cured product, and can be suitably used for sealing electronic components such as semiconductor devices. Resin compositions for sealing semiconductor elements such as power semiconductors, resin compositions for wafer sealing, resin compositions for forming pseudo wafers, sealing resin compositions for forming automotive electronic control units, sealing for forming wiring boards. It can be used for various purposes such as resin compositions.
Furthermore, by sealing electronic components such as semiconductor elements with the resin composition of this embodiment, electronic devices such as semiconductor devices can be obtained.

For example, in the present embodiment, the encapsulating resin composition is used for encapsulating a power semiconductor element that satisfies any of the following conditions (i) to (iv).
(i) Semiconductor element with power consumption of 2.0 W or more (ii) Semiconductor element made of one or more semiconductors selected from the group consisting of SiC, GaN, Ga ₂ O ₃ and diamond (iii) Voltage of 1.0 V or more (iv) Semiconductor element with a power density of 10 W/cm ³ or more The semiconductor device will be described below.

(semiconductor device)
In this embodiment, a semiconductor device is formed by sealing a semiconductor element with the resin composition according to this embodiment.
FIG. 1 is a cross-sectional view showing the configuration of a semiconductor device 100. The semiconductor device 100 shown in FIG. 1 includes a semiconductor element 20 mounted on a substrate 30 and a sealing material 50 that seals the semiconductor element 20.
The semiconductor device 20 is, for example, a power semiconductor device that satisfies any of the conditions (A) to (C) described above.
The sealing material 50 is made of a cured product obtained by curing the resin composition in this embodiment.

Further, FIG. 1 illustrates a case where the board 30 is a circuit board. In this case, as shown in FIG. 1, for example, a plurality of solder balls 60 are formed on the other surface of the substrate 30 opposite to the one surface on which the semiconductor element 20 is mounted. The semiconductor element 20 is mounted on the substrate 30 and electrically connected to the substrate 30 via wires 40. On the other hand, the semiconductor element 20 may be flip-chip mounted on the substrate 30. Here, the wire 40 is made of copper, for example.

The sealing material 50 seals the semiconductor element 20 so as to cover, for example, one surface of the semiconductor element 20 facing the substrate 30 and the other surface on the opposite side. In the example shown in FIG. 1, a sealing material 50 is formed to cover the other surface and side surfaces of the semiconductor element 20. The encapsulant 50 can be formed, for example, by encapsulant molding a resin composition using a known method such as a transfer molding method or a compression molding method.

In this embodiment, since the sealing material 50 is formed using the resin composition in this embodiment described above, it is possible to improve the reliability and heat resistance of the semiconductor device 100.

FIG. 2 is a cross-sectional view showing another configuration example of the semiconductor device 100. The semiconductor device 100 shown in FIG. 2 uses a lead frame as the substrate 30. In this case, the semiconductor element 20 is mounted, for example, on the die pad 32 of the substrate 30 and electrically connected to the outer lead 34 via the wire 40. The semiconductor element 20 is, for example, a power semiconductor element, similar to the example shown in FIG. Moreover, the sealing material 50 is formed using the resin composition in this embodiment in the same manner as the example shown in FIG.

It should be noted that the present invention is not limited to the above-described embodiments, and any modifications, improvements, etc. that can achieve the purpose of the present invention are included in the present invention.

Next, examples of the present invention will be described.
(Examples 1 to 6, Comparative Examples 1 to 4)
(Preparation of resin composition for sealing)
For each Example and each Comparative Example, a sealing resin composition was prepared as follows.
First, the components shown in Table 1 were mixed using a mixer. Next, the resulting mixture was roll-kneaded, cooled and pulverized to obtain a sealing resin composition in the form of powder.

Details of each component in Table 1 are as follows. Moreover, the blending ratio of each component shown in Table 1 indicates the blending ratio (mass %) to the entire resin composition.
Moreover, in the following, epoxy resin 1 and phenolic resin curing agent 1 were manufactured using the method described in International Publication No. 2013/136685.

Inorganic filler 1: Fused spherical silica, FB-560, manufactured by Denka, average particle size 29.5 μm
Inorganic filler 2: Fused spherical silica, FB-105, manufactured by Denka, average particle size 10.5 μm
Epoxy resin 1: Polyvalent MAR type epoxy resin represented by the following general formula (13A), epoxy equivalent: 207 g/eq

(In the above general formula (13A), the two Y's each independently represent a glycidylated phenyl group represented by the following formula (13B) or the following formula (13C), and X is a glycidylated phenyl group represented by the following formula (13D). Or represents a glycidylated phenylene group represented by the following formula (13E). n represents a number of 0 or more.)

Phenolic resin curing agent 1: polyvalent MAR type phenolic resin represented by the following general formula (12A), phenolic hydroxyl group equivalent: 135 g/eq

(In the above general formula (12A), the two Y's each independently represent a hydroxyphenyl group represented by the following formula (12B) or the following formula (12C), and X is the following formula (12D) or Represents a hydroxyphenylene group represented by the following formula (12E). n represents a number of 0 or more.)

Maleimide resin 1: Phenylmethane maleimide, BMI-2300, manufactured by Daiwa Kasei Co., Ltd., softening point 70-145°C
Maleimide resin 2: Bisphenol A diphenyl ether bismaleimide, BMI-4000, manufactured by Daiwa Kasei Co., Ltd., softening point 134-163°C
Maleimide resin 3: 1,6'-bismaleimide-(2,2,4-trimethyl)hexane, BMI-TMH, manufactured by Daiwa Kasei Co., Ltd., softening point 73-110°C
Curing accelerator 1: 2-phenylimidazole, Curesol 2PZ-PW, Shikoku Kasei Co., Ltd. Silane coupling agent 1: N-phenylaminopropyltrimethoxysilane, CF-4083, Dow Toray Co., Ltd. Colorant 1: Carbon black, # 5. Mitsubishi Chemical mold release agent 1: Carnauba wax, TOWAX-132, Toagosei ion scavenger 1: Hydrotalcite compound, DHT-4H, Kyowa Kagaku low stress agent 1: Epoxy polyether modified Silicone oil, FZ-3730, manufactured by Dow Toray

Next, the obtained sealing resin composition was evaluated as follows. The evaluation results are also shown in Table 1.

(DMA measurement)
The resin compositions of each example were injection molded using a transfer molding machine (KTS-15 manufactured by Kotaki Seiki Co., Ltd.) at a mold temperature of 175° C., an injection pressure of 6.9 MPa, and a curing time of 120 seconds, to a size of 10 mm x 4 mm x 4 mm. A cured product was obtained, and after curing at 200°C for 4 hours, it was used as a test piece.
In accordance with JIS K 6911, measurements were carried out using a DMA measuring device (manufactured by Seiko Instruments) under the conditions of a measurement temperature range of 0°C to 400°C, a heating rate of 5°C/min, and 10Hz, and the tan δ chart of the test piece was I got it.
Table 1 shows the presence or absence of peaks in the temperature range of 200 to 300°C and the temperature range of 300 to 400°C for the tan δ charts obtained in each example.
Furthermore, from the obtained measurement results, storage modulus E' (GPa), Tan δ, and glass transition temperature Tg1 (° C.) at room temperature (25° C.) and 260° C. were calculated. Note that Tg1 was determined from the peak value of tan δ.
FIG. 3 shows a measurement chart of tan δ of Example 1 and Comparative Example 2.

(TMA measurement)
The thermosetting resin composition obtained in each example was compression molded under conditions of a molding temperature of 175° C. for 3 minutes and a post mode cure of 175° C. for 4 hours to obtain a cured product. Measurement was performed using a thermomechanical analyzer (manufactured by Seiko Instruments, DMS6100) under the conditions of a nitrogen flow rate of 150 mL/min, a temperature increase rate of 10° C./min, a frequency of 10 Hz, and a measurement temperature range of 30 to 350° C. in a two-handed mode. Glass transition temperature Tg2 (℃), average coefficient of linear expansion α1 (ppm/℃) in the plane direction (XY direction) in the range from 40℃ to 80℃, average in the plane direction (XY direction) in the range from 270℃ to 300℃ The linear expansion coefficient α2 (ppm/°C) was calculated.

(Bending strength/flexural modulus)
The resin composition obtained in each example was injected using a transfer molding machine (KTS-15 manufactured by Kotaki Seiki Co., Ltd.) at a mold temperature of 175°C, an injection pressure of 6.9 MPa, and a curing time of 120 seconds. This was molded to obtain a cured product measuring 10 mm x 4 mm x 4 mm, which was then cured at 200° C. for 4 hours to obtain a test piece.
The flexural strength (MPa) and flexural modulus (GPa) of the obtained test piece at room temperature (25° C.) and 260° C. were measured in accordance with JIS K 6911.

(gel time)
The time (seconds) from when the resin composition obtained in each example was placed on a hot plate with a surface temperature of 175°C until it became tack-free was measured and defined as the gel time.

(Moisture resistance reliability (HAST test))
A TEG (Test Element Group) chip (3.5 mm x 3.5 mm) equipped with an aluminum electrode pad was mounted on the die pad portion of a lead frame whose surface was plated with Ag. Next, wire bonding was performed on the electrode pads of the TEG chip, the outer lead portions of the lead frame, and a bonding wire made of a copper alloy containing 99.9% by mass of Cu at a wire pitch of 120 μm. The resulting structure was encapsulated using a encapsulating resin composition using a low-pressure transfer molding machine under conditions of a mold temperature of 175° C., an injection pressure of 10.0 MPa, and a curing time of 2 minutes. A semiconductor package was manufactured. Thereafter, the obtained semiconductor package was post-cured at 175° C. for 4 hours to obtain a test semiconductor device.
The obtained test semiconductor device was left standing in an environment of temperature: 130° C., humidity: 85% RH, and voltage: 20 V, and the resistance value was measured every 40 hours up to 240 hours. A resistance value of 1.2 times or more of the initial value was judged as a failure, a case where the resistance value was passed for 200 hours or more was judged as good, and a case where the resistance value was failed before 200 hours was judged as poor.

From Table 1, in each Example, semiconductor devices with excellent bending strength and bending elastic modulus of cured resin compositions and excellent reliability were obtained.

Claims (10)

(A) epoxy resin,
(B) a phenolic resin curing agent; and (C) a maleimide compound.
At least one of the components (A) and (B) is a polyaromatic resin (MAR),
In the chart of the loss tangent (tan δ) of the cured product of the sealing resin composition measured by dynamic mechanical analysis (DMA) at a measurement temperature range of 0 ° C. to 400 ° C. and a temperature increase rate of 5 ° C./min, A sealing resin composition that does not have a peak in the temperature range of 200 to 300°C, but has a peak in the temperature range of 300 to 400°C. In the sealing resin composition, the equivalent ratio (EP/OH) of the number of epoxy groups EP in the component (A) to the number OH of phenolic hydroxyl groups in the component (B) is 1.5 or more and 10 or less. The sealing resin composition according to claim 1. Claim 1, wherein the content of the component (C) is 10 parts by mass or more and 40 parts by mass or less, based on a total of 100 parts by mass of the components (A) to (C) in the sealing resin composition. Or the sealing resin composition according to 2. The glass transition temperature Tg1 of the cured product measured by the DMA and the cured product measured by thermomechanical analysis (TMA) under the conditions of a measurement temperature range of 0°C to 320°C and a heating rate of 5°C/min. The sealing resin composition according to any one of claims 1 to 3, wherein the difference (Tg1-Tg2) from glass transition temperature Tg2 is 50°C or more and 150°C or less. The sealing resin composition according to any one of claims 1 to 4, wherein both of the components (A) and (B) are the polyaromatic ring type resin (MAR). The sealing resin composition according to claim 5, wherein both of the components (A) and (B) are the polyaromatic ring type resin (MAR) having trifunctionality or more. The sealing resin composition according to any one of claims 1 to 6, wherein the component (A) contains a bifunctional to tetrafunctional epoxy resin having a naphthalene skeleton. The sealing resin composition according to any one of claims 1 to 7, wherein the component (C) has a softening point of 170°C or less. Component (D): The sealing resin composition according to any one of claims 1 to 8, further comprising an imidazole compound. The following conditions (i) to (iv):
(i) Semiconductor element with power consumption of 2.0 W or more (ii) Semiconductor element made of one or more semiconductors selected from the group consisting of SiC, GaN, Ga ₂ O ₃ and diamond (iii) Voltage of 1.0 V or more (iv) A semiconductor device having a power density of 10 W/cm ³ or more. The encapsulating resin composition according to any one of claims 1 to 9, which is used for encapsulating a power semiconductor device. thing.

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