JP2018115233A - Resin composition for encapsulation and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To achieve an encapsulation material excellent in temperature cycle credibility under high temperature environment and durability to long term use in a semiconductor device having a power semiconductor element.SOLUTION: A resin composition for encapsulation contains a specific maleimide resin, a thermosetting resin and an inorganic filler. Content of the specific maleimide resin is 30 mass% to 65 mass% based on whole resin composition for encapsulation.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sealing resin composition and a semiconductor device.

  Various investigations have been made on resin compositions used to seal semiconductor elements. Examples of such techniques include those described in Patent Document 1 and Patent Document 2.

  Patent Document 1 discloses a technique related to a resin composition for a sealing material containing an epoxy resin. Specifically, it comprises at least one selected from the group consisting of epoxy resins, acid anhydrides, amine compounds and phenolic compounds, organic group-containing silsesquioxane, silica and composite metal hydroxide, and A resin composition for a sealing material is described in which at least one selected from the group consisting of the epoxy resin, acid anhydride, amine compound and phenol compound has a melting point of 100 ° C. or higher.

  On the other hand, Patent Document 2 includes a bismaleimide compound, an allyl compound, and a polymerization initiator having a specific structure as a resin composition for encapsulating a semiconductor that can sufficiently suppress wafer warpage and has excellent moldability. A resin composition for encapsulating a semiconductor is disclosed.

JP 2014-028928 A JP 2014-001289 A

The sealing resin composition is used to form a sealing material for sealing a semiconductor element as described above. With respect to such a sealing material, it is important that a normal silicon device can withstand use under a temperature environment of about 175 ° C., for example. However, in a semiconductor device including a power semiconductor element using a wide band gap material such as SiC, GaN, Ga ₂ O ₃ , or diamond, temperature cycle reliability in a higher temperature environment and durability against long-term use It has been required to realize a sealing material excellent in the above.

As a result of intensive studies based on these circumstances, the present inventors have a high heat resistance and a specific maleimide resin having a long distance between cross-linking points, a thermosetting resin, and an inorganic filler, and a sealing resin composition. By optimizing the compounding quantity of specific maleimide resin, it discovered that the temperature cycle reliability of the hardened | cured material of the resin composition for sealing could be improved, and came to complete this invention.
According to the present invention,
(A) a maleimide resin represented by the general formula (1);
(B) a thermosetting resin;
(C) an inorganic filler;
A sealing resin composition comprising:
The content of the maleimide resin represented by the general formula (1) (A) is 30% by mass or more and 65% by mass with respect to the whole sealing resin composition (excluding the component (C) inorganic filler). The following sealing resin composition is provided.

(In the formula (1), X ₁ is a divalent organic group having 1 to 18 carbon atoms, a group represented by the formula “—SO ₂ —”, a group represented by “—CO—”, an oxygen atom or a single atom. In addition, each R ₁ is independently a hydrogen atom, a substituent having 1 to 6 carbon atoms or an unsubstituted hydrocarbon group. And a cured product of the resin composition for stopping.

  ADVANTAGE OF THE INVENTION According to this invention, the resin composition for sealing excellent in temperature cycle reliability and a semiconductor device using the same can be provided.

It is sectional drawing which shows an example of the semiconductor device which concerns on this embodiment. It is sectional drawing which shows an example of the semiconductor device which concerns on this embodiment. It is a cross-sectional schematic diagram which shows an example of the vehicle-mounted electronic control unit which concerns on this embodiment.

  Hereinafter, embodiments will be described with reference to the drawings. In all the drawings, the same reference numerals are given to the same components, and the description will be omitted as appropriate.

  First, the sealing resin composition according to this embodiment will be described.

The sealing resin composition of the present embodiment is
(A) a maleimide resin represented by the general formula (1);
(B) a thermosetting resin;
(C) an inorganic filler;
(A) The content of the maleimide resin represented by the general formula (1) is 30 mass with respect to the entire sealing resin composition (excluding the component (C) inorganic filler). % To 65% by mass.

(In the formula (1), X ₁ is a divalent organic group having 1 to 18 carbon atoms, a group represented by the formula “—SO ₂ —”, a group represented by “—CO—”, an oxygen atom or a single atom. In addition, each R ₁ is independently a hydrogen atom, a substituent having 1 to 6 carbon atoms or an unsubstituted hydrocarbon group.) The present inventor has high heat resistance and a distance between cross-linking points. In a sealing resin composition containing a long maleimide resin represented by the general formula (1), a thermosetting resin, and an inorganic filler, a specific maleimide resin, crosslinking of the thermosetting resin, and an inorganic filler It was noticed that an optimal cross-linked structure of the encapsulating resin composition can be obtained by combining the above.
As a result of studying based on such viewpoints, it is possible to control the optimal crosslinking structure of the sealing resin composition by optimizing the blending amount of the maleimide resin represented by the general formula (1). The present inventors have found that the temperature cycle reliability and high-temperature long-term storage characteristics of the cured product of the resin composition can be improved, and the present invention has been completed.
Although the detailed mechanism is not clear, by optimizing the blending amount of the maleimide resin represented by the general formula (1), the cross-linking structure with the thermosetting resin is optimized, and the temperature cycle reliability is as described above. It is thought that high-temperature long-term storage characteristics can be improved.

According to this embodiment, by using the sealing resin composition, it is possible to realize a sealing material excellent in temperature cycle reliability and high-temperature long-term storage characteristics and a semiconductor device using the same.

Moreover, the structure excellent in temperature cycle reliability and high temperature long-term storage characteristics is realizable by using the resin composition for sealing. Such a structure is provided with a cured product of a sealing resin composition. For example, an electronic device or wafer in which a semiconductor element such as a power semiconductor is sealed with a cured product of a sealing resin composition These include a wafer level package in which the circuit surface is sealed with a cured product of a sealing resin composition, a cured product of a sealing resin composition used for a pseudo wafer, and the like. Moreover, as said structure, not only a general electronic device but a vehicle-mounted electronic control unit (ECU) and the wiring board used for this are mentioned. The wiring board has a structure in which metal wiring is sealed with a cured product of a sealing resin composition. The on-vehicle electronic control unit has a structure in which the wiring board and a plurality of electronic elements mounted on the wiring board are sealed with a cured product of the sealing resin composition.

  Moreover, since the hardened | cured material of the resin composition for sealing of this embodiment can have a high glass transition temperature, it can also be used suitably for use in high temperature environments, such as a vehicle. For this reason, the resin composition for sealing can also be used as a fixing member for the rotor.

  Moreover, the resin composition for sealing of this embodiment may have predetermined shapes, such as a granular form, a tablet form, or a sheet form, for example. Thereby, it becomes easy to encapsulate the semiconductor element using a known molding method such as transfer molding, injection molding, and compression molding. In the present embodiment, the granular form is an aggregate obtained by solidifying powders of the sealing resin composition, and the tablet form has a predetermined shape by tableting the sealing resin composition at high pressure. It is a modeling object modeled so that it may have, and a sheet form means that it is a resin film which consists of a resin composition for closure which has a sheet form or a roll form which can be rolled up, for example. The resin composition for sealing in the form of granules, tablets or sheets may be in a semi-cured state (B stage state). A solid state can be obtained at room temperature (for example, 25 ° C.). Thereby, the resin composition for sealing excellent in the formability which is the characteristic which is easy to provide shapes, such as a granular form and a tablet form, is realizable.

Hereinafter, each component which comprises the resin composition for sealing in this embodiment is demonstrated.
((A) Maleimide resin represented by general formula (1))
The sealing resin composition of this embodiment contains a maleimide resin represented by the general formula (1).
Thereby, glass transition temperature can be raised, a crosslinked structure can be optimized, and the temperature cycle reliability and high temperature long-term storage characteristic as a sealing material can be improved more effectively.

(In the formula (1), X ₁ is a divalent organic group having 1 to 18 carbon atoms, a group represented by the formula “—SO ₂ —”, a group represented by “—CO—”, an oxygen atom or a single atom. In the present embodiment, R ₁ is a hydrogen atom, a substituent having 1 to 6 carbon atoms or an unsubstituted hydrocarbon group. The content of A) maleimide resin is, for example, preferably 30% by mass or more and 35% by mass or more with respect to the entire sealing resin composition (excluding the component (C) inorganic filler). More preferably, it is more preferably 40% by mass or more. (A) By making content of maleimide resin more than the said lower limit, the heat resistance as a sealing material can be improved effectively, and also internal stress can be reduced with the flexible frame | skeleton.

  The content of (A) maleimide resin is, for example, preferably 65% by mass or less, and 60% by mass or less with respect to the entire sealing resin composition (excluding (C) the inorganic filler). Is more preferable, and it is further more preferable that it is 55 mass% or less. (A) By making content of maleimide resin below the said upper limit, the handleability at the time of resin composition preparation for sealing and the toughness as a resin composition for sealing can be improved.

Moreover, in this embodiment, the whole sealing resin composition (excluding (C) inorganic filler) means that the content of (C) inorganic filler is excluded from the whole sealing resin composition content. Refers to the content.
((B) thermosetting resin)
The sealing resin composition of this embodiment contains a thermosetting resin.
Examples of such thermosetting resins include maleimide resins (except for those corresponding to (A) maleimide resins), benzoxazine resins, phenol resins, epoxy resins (epoxy compounds), urea (urea) resins, Examples include melamine resins, unsaturated polyester resins, polyurethane resins, diallyl phthalate resins, silicone resins, cyanate resins, polyimide resins, polyamideimide resins, and benzocyclobutene resins. These may be used alone or in combination of two or more.
Among these, (A) maleimide resin capable of reacting with maleimide resin (except for those corresponding to (A) maleimide resin), benzoxazine resin, phenol resin and the like are preferable.

  The softening point of the thermosetting resin is preferably a temperature lower than the softening point of the (A) maleimide resin. The softening point is preferably 140 ° C. or lower, more preferably 120 ° C. or lower, and further preferably 100 ° C. or lower. (B) By making the softening point of a thermosetting resin below the said upper limit, the handleability at the time of resin composition preparation for sealing improves.

Among these, in the present embodiment, as the resin composition for sealing, (B-1) maleimide resin (excluding those corresponding to (A) maleimide resin), (B-2) benzoxazine compound, (B -3) It is preferable to contain a phenol resin. Thereby, the fluidity | liquidity and sclerosis | hardenability as a resin composition can be improved with sufficient balance.
(B-1) Maleimide resin (excluding those corresponding to (A) maleimide resin)
(B-1) As the maleimide resin, for example, a compound represented by the following formula (2) can be used. Thereby, a glass transition temperature can be raised.

(In the formula (2), R ₂ is a divalent organic group having 1 to 30 carbon atoms, may contain one or more of the oxygen atoms and nitrogen atoms.)
In the above formula (2), from the viewpoint of improving the high temperature storage characteristics of the sealing material, it is preferred that R ₂ is an organic group containing an aromatic ring.

  As a compound shown to the said Formula (2) which can be applied in this embodiment, the compound shown below is mentioned, for example.

Moreover, the compound shown to following formula (4) can be used for (B-1) maleimide resin, for example. Since such maleimide resin has low crystallinity and a very low melting point, it is possible to further improve the handling property at the time of producing the sealing resin composition while maintaining a high glass transition temperature.

(In Formula (4), n is an integer of 10 or less, preferably an integer of 5 or less. R ₃ is each independently a hydrogen atom or a substituted or unsubstituted hydrocarbon group having 1 to 4 carbon atoms. .)
(B-2) Benzoxazine resin Examples of the benzoxazine resin include compounds having two or more benzoxazine rings.

  For example, at least one of a compound represented by the following formula (5) and a compound represented by the following formula (7) can be included, and at least a compound represented by the following formula (5) is more preferably included. Thereby, mechanical characteristics can be improved more effectively without reducing the heat resistance of the sealing material.

(In the formula (5), R ₄ is a divalent organic group having 1 to 30 carbon atoms, may contain one or more of the oxygen atoms and nitrogen atoms.)
From the viewpoint of improving the high-temperature storage characteristics of the encapsulant, R ₄ is more preferably an organic group containing an aromatic ring. In the present embodiment, for example, the following compounds can be used as the compound represented by the above formula (5).

(In the formula (7), R ₅ is a divalent organic group having 1 to 30 carbon atoms, an oxygen atom, a nitrogen atom, and may .R ₆ also include one or more of the sulfur atom, respectively Independently an aromatic hydrocarbon group having 1 to 12 carbon atoms.)
(B-3) Phenol resin Although a phenol resin is not specifically limited, For example, Novolak-type resin, such as a phenol novolak resin, a cresol novolak resin, a bisphenol novolak; Polyvinylphenol; Multifunctional phenol resin, such as a trismethane phenol-type resin; Modified phenol resins such as modified phenol resins and dicyclopentadiene modified phenol resins; Aralkyl resins such as phenol aralkyl resins having a phenylene skeleton and / or biphenylene skeleton, and naphthol aralkyl resins having a phenylene and / or biphenylene skeleton; bisphenol A, bisphenol Bisphenol compounds such as F; one or two or more selected from resol type phenol resins can be included. From the viewpoint of glass transition temperature and water absorption, it is preferable to use a trismethanephenol type resin or a phenol aralkyl resin having a biphenylene skeleton.

  In the present embodiment, the lower limit of the content of the (B) thermosetting resin in the organic component of the sealing resin composition (excluding those corresponding to (A) maleimide resin) is, for example, a sealing resin It is preferably 30% by mass or more, more preferably 35% by mass or more, and further preferably 40% by mass or more based on the entire composition (excluding the component (C) inorganic filler). (B) By making content of a thermosetting resin more than the said lower limit, the handleability at the time of resin composition preparation for sealing can be improved.

The upper limit of the content of the (B) thermosetting resin (excluding those corresponding to the (A) maleimide resin) is, for example, the entire sealing resin composition (however, the component (C) inorganic filler). Is preferably 70% by mass or less, more preferably 65% by mass or less, and still more preferably 60% by mass or less. (B) By making content of a thermosetting resin below the said upper limit, the resin composition which made compatible reduction of internal stress and high heat resistance is obtained.
(C) Inorganic filler The sealing resin composition of the present embodiment includes (C) an inorganic filler. Thereby, the rigidity of the sealing material obtained from the resin composition for sealing can be further improved.

  Examples of the inorganic filler (C) include one selected from titanium oxide, zirconium oxide, silica, calcium carbonate, boron carbide, clay, mica, talc, wollastonite, glass beads, milled carbon, graphite, and the like. The above is used.

  Among these, it is preferable to use silica, and one or more selected from fused spherical silica, fused crushed silica, and crystalline silica can be included. Among these, it is more preferable to contain fused spherical silica from the viewpoint of improving the filling property of the encapsulating resin composition, the high-temperature long-term storage characteristics of the encapsulant, and the like.

For example, the silica preferably has a SiO ₂ content of 99.8% by mass or more. By using such high-purity silica, it becomes easy to realize a sealing material having good heat resistance and mechanical properties while reducing the amount of ionic impurities such as metal impurities. From the viewpoint of more effectively improving the high-temperature long-term storage characteristics of the sealing material, the content of SiO ₂ in silica is preferably 99.9% by mass or more.

  In the present embodiment, the content of the (C) inorganic filler in the encapsulating resin composition is preferably 60% by mass or more, for example, 65% by mass or more with respect to the entire encapsulating resin composition. It is more preferable that it is 70 mass% or more. (C) By making content of an inorganic filler more than the said lower limit, the rigidity as a sealing material can be improved effectively.

The content of (C) inorganic filler is, for example, preferably 95% by mass or less, more preferably 93% by mass or less, and 90% by mass or less, with respect to the entire sealing resin composition. More preferably. (C) By making content of an inorganic filler below the said upper limit, the reliability of an apparatus etc. can be improved further.
(D) Heterocyclic Compound The sealing resin composition of the present embodiment can contain, for example, (D) a heterocyclic compound. The heterocyclic compound has a function of improving the adhesion between the sealing resin composition and other members other than the sealing material in the apparatus.

In the present embodiment, examples of the heterocyclic compound include monocyclic 5-membered rings such as pyrrole ring, imidazole ring, pyrazole ring and triazole ring, and 6-membered rings such as pyridine ring, pyrimidine ring and triazine ring. It is done. Examples of the bicyclic ring include an indole ring, a benzimidazole ring, a benzotriazole ring, a quinoline ring, a bipyridyl ring, and a phenanthroline ring. These heterocycles may be condensed with an allocyclic ring composed only of aromatic carbon such as a benzene ring and a naphthalene ring. Although these heterocyclic compounds do not depend on the presence or absence of a functional group, compounds in which a basic functional group is directly bonded to the heterocyclic ring are preferable. These can be used alone or in combination of two or more.
In addition, the content of the heterocyclic compound is preferably 0.01% by mass or more, more preferably 0.03% by mass or more, for example, with respect to the entire sealing resin composition. It is particularly preferable that the content is at least mass%. By making content of a heterocyclic compound more than the said lower limit, the adhesiveness of a resin composition and another member can be improved effectively.
Further, the content of the heterocyclic compound is preferably, for example, 1% by mass or less, more preferably 0.9% by mass or less, and 0.8% by mass or less, with respect to the entire sealing resin composition. It is particularly preferred that By making the content of the heterocyclic compound not more than the above upper limit value, the handling property at the time of producing the sealing resin composition can be improved.

In addition, when an imidazole and a triazole type compound are used as a heterocyclic compound, since it has a function which accelerates | stimulates (A) polymerization reaction with a maleimide resin, the adhesion aid can exhibit the function as a curing catalyst.
(Curing accelerator)
The sealing resin composition of the present embodiment can further contain a curing accelerator. Any curing accelerator may be used as long as it accelerates the curing of (A) maleimide resin or (B) thermosetting resin.

  In the present embodiment, the curing accelerator is, for example, a phosphorus atom-containing compound such as an organic phosphine, a tetra-substituted phosphonium compound, a phosphobetaine compound, an adduct of a phosphine compound and a quinone compound, an adduct of a phosphonium compound and a silane compound; -Amidines and tertiary amines exemplified by imidazoles such as phenylimidazole and 2-methylimidazole; 1,8-diazabicyclo [5.4.0] undecene-7, benzyldimethylamine and the like; One type or two or more types selected from nitrogen atom-containing compounds such as salts can be included.

  In this embodiment, it is preferable that content of the hardening accelerator in the resin composition for sealing is 0.01 mass% or more with respect to the whole resin composition for sealing, for example, and 0.03 mass%. More preferably, it is more preferably 0.05% by mass or more. By making content of a hardening accelerator more than the said lower limit, the sclerosis | hardenability of a resin composition can be improved effectively.

Moreover, it is preferable that it is 5 mass% or less with respect to the whole resin composition for sealing, for example, as for content of a hardening accelerator, it is more preferable that it is 3 mass% or less, and it is 1 mass% or less. Particularly preferred. By making content of a hardening accelerator into the said upper limit or less, the fluidity | liquidity of the resin composition for sealing can be improved.
(Silane coupling agent)
The sealing resin composition of this embodiment can further contain a silane coupling agent.
Thereby, the further improvement of the adhesiveness of the resin composition for sealing can be aimed at.

  The silane coupling agent can be included in the sealing resin composition by mixing, for example, an inorganic filler (C) surface-treated with a silane coupling agent with multiple components. On the other hand, (C) the inorganic filler is not subjected to the above surface treatment, and the silane coupling agent is put into a mixer or the like together with each component, and mixed to thereby remove the silane coupling agent from the sealing resin composition. It may be included.

  As the silane coupling agent, for example, various silane compounds such as epoxy silane, mercapto silane, amino silane, alkyl silane, ureido silane, vinyl silane, and methacryl silane can be used.

Examples of these include vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxy. Silane, 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, methyl Triethoxysilane, N-β- (N-vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, hexamethyldisilane, vinyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, Examples thereof include silane coupling agents such as 3-acryloxypropyltrimethoxysilane and 3-triethoxysilyl-N- (1,3-dimethylbutylidene) propylamine hydrolyzate.

  These may be used individually by 1 type, and may be used in combination of 2 or more types. Among these coupling agents, it is preferable to contain an aminosilane such as phenylaminopropyltrimethoxysilane.

  In this embodiment, it is preferable that content of the silane coupling agent in the resin composition for sealing is 0.01 mass% or more with respect to the whole resin composition for sealing, for example, and 0.03 mass % Or more is more preferable, and 0.05 mass% or more is particularly preferable. By making content of a silane coupling agent more than the said lower limit, the fluidity | liquidity and adhesiveness of a resin composition can be improved effectively.

Further, the content of the silane coupling agent is, for example, preferably 5% by mass or less, more preferably 3% by mass or less, and more preferably 1% by mass or less with respect to the entire sealing resin composition. Is particularly preferred. By making content of a silane coupling agent below the said upper limit, sclerosis | hardenability of the resin composition for sealing can be improved.
(Other ingredients)
In the sealing resin composition of the present embodiment, if necessary, ion scavengers exemplified by inorganic ion exchangers such as hydrotalcites and polyvalent metal acid salts; low stress materials such as silicone rubber Natural oils such as carnauba wax, synthetic waxes, higher fatty acids such as zinc stearate and release agents such as metal salts thereof or paraffin; colorants such as carbon black and bengara; aluminum hydroxide, magnesium hydroxide, zinc borate Flame retardants such as zinc molybdate and phosphazene; various additives such as antioxidants may be appropriately blended. These compounding amounts are arbitrary.
In the present embodiment, the ratio of the blending amount excluding the inorganic filler (C) in the sealing resin composition is preferably 5% by mass or more with respect to the entire sealing resin composition, for example. It is more preferably 7% by mass or more, and further preferably 10% by mass or more. By making the ratio of the blending amount excluding the inorganic filler (C) in the encapsulating resin composition equal to or higher than the above lower limit value, the reliability of the apparatus and the like can be further improved.
Further, the proportion of the blending amount excluding the inorganic filler (C) in the sealing resin composition is preferably 40% by mass or less, for example, 35% by mass with respect to the entire sealing resin composition. More preferably, it is more preferably 30% by mass or less. By setting the ratio of the blending amount excluding the inorganic filler (C) in the sealing resin composition to be equal to or lower than the above upper limit value, the rigidity as the sealing material can be effectively improved.

  The method for producing the sealing resin composition of the present embodiment is not particularly limited. For example, the above-described components are mixed by known means, and further melt-kneaded by a kneader such as a roll, a kneader or an extruder, Granules pulverized after cooling, tablets formed into tablets after pulverization, and if necessary, the above pulverized ones are sieved, centrifugal milling method, hot cut method etc. Granules produced by a condylar method with adjusted fluidity and the like can be used as the sealing resin composition.

  Moreover, the sheet-like sealing resin composition can be obtained by forming a film of the sealing resin composition having a varnish shape. For example, it can be obtained by removing the solvent from the coating film obtained by applying the sealing resin composition. In such a sheet-like sealing resin composition, the solvent content can be 5% by mass or less based on the whole.

Hereinafter, the characteristic of the hardened | cured material of the resin composition for sealing of this embodiment is demonstrated.
The sealing resin composition of the present embodiment includes (A) a maleimide resin represented by the general formula (1), (B) a thermosetting resin, and (C) an inorganic filler. Average line calculated in the range of 50 ° C. to 70 ° C. in a cured product obtained by curing the sealing resin composition at 200 ° C. for 120 seconds and further post-curing at 250 ° C. for 4 hours. The sealing resin composition has a ratio (α2 / α1) of an average linear expansion coefficient α2 calculated in the range of 310 ° C. to 340 ° C. with respect to the expansion coefficient α1 of 1.0 or more and 7.0 or less.

(In the formula (1), X ₁ is a divalent organic group having 1 to 18 carbon atoms, a group represented by the formula “—SO ₂ —”, a group represented by “—CO—”, an oxygen atom or a single atom. In addition, each R ₁ is independently a hydrogen atom, a substituent having 1 to 6 carbon atoms or an unsubstituted hydrocarbon group.)
The lower limit value of the glass transition temperature of the cured product obtained by curing the resin composition for sealing of this embodiment at 200 ° C. for 120 seconds and then post-curing at 250 ° C. for 4 hours is, for example, 180. It is 200 degreeC or more, Preferably it is 200 degreeC or more, More preferably, it is 250 degreeC or more. Thereby, heat resistance can be improved and temperature cycle reliability can be improved further. Moreover, although the upper limit of the glass transition temperature of the hardened | cured material of the said sealing resin composition is not specifically limited, For example, it is 350 degrees C or less. As a method for measuring the glass transition temperature, for example, a thermomechanical analyzer (manufactured by Seiko Instruments Inc., TMA100) can be used.

The average of the cured product obtained by curing the resin composition for sealing of this embodiment at 200 ° C. for 120 seconds and then post-curing at 250 ° C. for 4 hours in a temperature range of 310 ° C. to 330 ° C. The upper limit of the linear expansion coefficient (α2) is, for example, 100 [10 ⁻⁶ / ° C.] or less, preferably 95 [10 ⁻⁶ / ° C.] or less, and more preferably 90 [10 ⁻⁶ / ° C.]. It is as follows. Thereby, the linear expansion coefficient at the time of a heat history can be made low, for example, the curvature of a semiconductor package can be suppressed. Moreover, the lower limit of the average linear expansion coefficient (α2) is not particularly limited, but may be, for example, 30 [10 ⁻⁶ / ° C.] or more.

The average of the cured product obtained by curing the resin composition for sealing of the present embodiment at 200 ° C. for 120 seconds and then post-curing at 250 ° C. for 4 hours in a temperature range of 50 ° C. to 70 ° C. The upper limit value of the linear expansion coefficient ratio of the average linear expansion coefficient (α2) in the temperature range of 310 ° C. to 330 ° C. with respect to the linear expansion coefficient (α1) is, for example, 7 or less, preferably 6.8 or less, More preferably, it is 6.6 or less. Thereby, since the fluctuation | variation of the linear expansion coefficient at the time of normal temperature and a heat history can be made small, a heat cycle characteristic can be improved. Moreover, the lower limit value of the linear expansion coefficient ratio is not particularly limited, but may be, for example, 1.1 or more. For example, a thermomechanical analyzer (manufactured by Seiko Instruments Inc., TMA100) can be used to measure the average linear expansion coefficient (α1) and the average linear expansion coefficient (α2).
After the resin composition for sealing of the present embodiment is cured at 200 ° C. for 120 seconds, the lower limit value of the flexural modulus at room temperature of the cured product that is post-cured at 250 ° C. for 4 hours is: For example, it is 5 GPa or more, preferably 7 GPa or more, more preferably 9 GPa or more. Thereby, the intensity | strength of the said hardened | cured material can be raised. Moreover, although the upper limit of the said bending elastic modulus is not specifically limited, For example, it is 20 GPa or less, Preferably it is 15 GPa or less, More preferably, it is 10 GPa or less. Thereby, the hardened | cured material excellent in stress relaxation is realizable. The flexural modulus at room temperature can be measured according to, for example, JIS K 6911.

  The encapsulating resin composition of the present embodiment includes a resin composition for encapsulating semiconductor elements such as general semiconductor elements and power semiconductors, a resin composition for encapsulating a wafer, a resin composition for forming a pseudo wafer, and an in-vehicle electronic device. It can be used for various applications such as a sealing resin composition for forming a control unit, a sealing resin composition for forming a wiring board, and a sealing resin composition for a rotor fixing member.

  Next, a semiconductor device will be described.

FIG. 1 is a cross-sectional view showing an example of a semiconductor device 100 according to the present embodiment. The semiconductor device 100 according to this embodiment includes a semiconductor element 20 mounted on a substrate 30 and a sealing material 50 that seals the semiconductor element 20. The semiconductor element 20 is a power semiconductor element formed of, for example, SiC, GaN, Ga ₂ O ₃ , or diamond. Moreover, the sealing material 50 is comprised by the hardened | cured material obtained by hardening | curing the resin composition for sealing which concerns on this embodiment.

In the semiconductor device 100 according to the present embodiment, the semiconductor element 20 is a power semiconductor element formed of SiC, GaN, Ga ₂ O ₃ , or diamond as described above, and can operate at a high temperature of 200 ° C. or higher. it can. Even in such a long-time use in a high-temperature environment, the sealing material 50 formed using the sealing resin composition according to the present embodiment can exhibit sufficient adhesion. For this reason, the reliability of the semiconductor device 100 can be improved. The semiconductor element 20 can be a power semiconductor element having an input power of 1.7 W or more, for example.

  In FIG. 1, the case where the board | substrate 30 is a circuit board is illustrated. 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 surface on which the semiconductor element 20 is mounted. The semiconductor element 20 is mounted on, for example, the substrate 30 and is electrically connected to the substrate 30 via the wire 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, for example, copper.

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

FIG. 2 is a cross-sectional view showing an example of the semiconductor device 100 according to the present embodiment, and shows an example different from FIG. A semiconductor device 100 shown in FIG. 2 uses a lead frame as the substrate 30. In this case, the semiconductor element 20 is mounted on, for example, the die pad 32 of the substrate 30 and is electrically connected to the outer lead 34 via the wire 40. The semiconductor element 20 is a power semiconductor element formed of SiC, GaN, Ga ₂ O ₃ , or diamond, as in the example shown in FIG. Moreover, the sealing material 50 is formed using the resin composition for sealing which concerns on this embodiment similarly to the example shown in FIG.

  Next, the manufacturing method of the vehicle-mounted electronic control unit 10 is demonstrated based on FIG.

  The in-vehicle electronic control unit 10 according to the present embodiment is manufactured as follows, for example. First, a plurality of electronic components 16 are mounted on at least one surface of the wiring board 12. Next, the plurality of electronic components 16 are encapsulated using an encapsulating resin composition. As the resin composition for sealing, those exemplified above can be used.

  Hereinafter, the manufacturing method of the vehicle-mounted electronic control unit 10 will be described in detail.

  First, a plurality of electronic components 16 are mounted on at least one surface of the wiring board 12. In the present embodiment, for example, a plurality of electronic components 16 can be mounted on one surface of the wiring board 12 and the other surface opposite to the one surface. Thereby, the vehicle-mounted electronic control unit 10 in which the electronic components 16 are mounted on both surfaces of the wiring board 12 as shown in FIG. 3 can be formed. On the other hand, the electronic component 16 may be mounted on only one surface of the wiring board 12 and the electronic component 16 may not be mounted on the other surface. In addition, as the wiring board 12 and the electronic component 16, what is normally used in this technical field is applicable.

  As shown in FIG. 3, the wiring board 12 has a flat plate shape, for example. In the present embodiment, for example, an organic substrate formed of an organic material such as polyimide can be used as the wiring substrate 12. The wiring board 12 may have, for example, a through hole 120 that penetrates the wiring board 12 and connects one surface to the other surface. In this case, the wiring provided on one surface of the wiring board 12 and the wiring provided on the other surface are electrically connected via the conductor pattern provided in the through hole 120.

  Next, the plurality of electronic components 16 are encapsulated using an encapsulating resin composition. Thereby, the sealing resin 14 for sealing the electronic component 16 is formed. In the present embodiment, for example, the sealing resin composition is molded so as to seal the wiring substrate 12 together with the electronic component 16. The vehicle-mounted electronic control unit 10 illustrated in FIG. 3 is obtained, for example, by sealing and molding one surface and the other surface of the wiring board 12 and the electronic component 16 mounted on the wiring board 12 with a sealing resin composition. be able to. In the present embodiment, a part or all of the wiring board 12 is sealed together with the plurality of electronic components 16 using the sealing resin composition. The in-vehicle electronic control unit 10 illustrated in FIG. 3 is sealed so as to seal the entire other part without sealing the connection terminal 18 of the wiring board 12 so that the connection terminal 18 is exposed, for example. It is obtained by molding the resin composition for use.

  It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.

Next, examples of the present invention will be described.
(Preparation of resin composition for sealing)
For each example and each comparative example, a sealing resin composition was prepared as follows.
According to the formulation shown in Table 1, each component was mixed with a mixer. Subsequently, after roll-kneading the obtained mixture, it cooled and grind | pulverized and the resin composition for sealing which is a granular material was obtained. Details of each component in Table 1 are as follows. Moreover, the mixture ratio of each component shown in Table 1 has shown the mixture ratio (mass%) with respect to the whole resin composition. Furthermore, “(A) Maleimide resin ratio” in Table 1 is the ratio of (A) maleimide resin in the component excluding (C) inorganic filler from the entire sealing resin composition. The same applies to “(B) ratio of thermosetting resin” in Table 1.
(A) Maleimide resin Maleimide resin 1: Compound having two maleimide groups represented by the following formula (manufactured by Daiwa Kasei Kogyo Co., Ltd., “BMI-4000”, softening point: 167 ° C.)

(B) Thermosetting resin Thermosetting resin 1: Compound having two or more maleimide groups represented by the following formula (manufactured by Daiwa Kasei Kogyo Co., Ltd., “BMI-2300”, softening point: 64 ° C.)

Thermosetting resin 2: benzoxazine compound represented by the following formula (Shikoku Kasei Co., Ltd., “Pd-type benzoxazine”, softening point: 75 ° C.)

Thermosetting resin 3: Trismethanephenol type resin (Maywa Kasei Co., Ltd., “MEH-7500”, softening point: 61 ° C.)
(C) Inorganic filler Inorganic filler 1: fused spherical silica (average particle size: 30 μm)
(D) Heterocyclic compound Heterocyclic compound 1: 2-hydroxy-N-1H-1,2,4-triazol-3-ylbenzamide (manufactured by ADEKA Corporation, “CDA-1M”)
(Curing accelerator)
Curing accelerator 1: 2-methylimidazole (manufactured by Shikoku Kasei Co., Ltd., “2MZ-H”)
(Silane coupling agent)
Silane coupling agent 1: Phenylaminopropyltrimethoxysilane (Toray Dow Corning Co., Ltd., “CF-4083”)
(Release agent)
Mold release agent: Montanic acid ester (manufactured by Clariant Japan, “Recove WE-4”)
(Coloring agent)
Colorant: Carbon black (Mitsubishi Chemical Corporation, “# 5”)
The softening point is
1484526591235_15.html
(Measured using Hitachi High-Tech Science Co., Ltd., DSC7020).

The obtained sealing resin composition was evaluated based on the following items.
(Temperature cycle test)
Using the obtained sealing resin composition, a low-pressure transfer molding machine (“MSL-06M” manufactured by Apic Yamada Co., Ltd.) was used, and the mold temperature was 200 ° C., the injection pressure was 10 MPa, and the curing time was 120 seconds. The package size was 114 mm × 30 mm, the thickness was 1.3 mm, the chip was not mounted, and the lead frame was made of Cu), and the semiconductor device for testing was manufactured by curing at 250 ° C. for 4 hours. The sealed test semiconductor device was cycled at −40 ° C. to 225 ° C., and the number of cycles in which package cracks and separation between members did not occur was measured.
(High temperature long-term storage characteristics)
Using a transfer molding apparatus, the obtained sealing resin composition was injection molded at a mold temperature of 200 ° C., an injection pressure of 9.8 MPa, and a curing time of 120 seconds to obtain a molded product having a diameter of 10 mmΦ × thickness of 4 mm. It was. Next, the obtained molded product was post-cured at 250 ° C. for 4 hours, and then dried at 150 ° C. for 16 hours to obtain a test piece, and the initial mass was measured. Then, it was put into an oven at 250 ° C., taken out after 50, 100, 250, 500, and 1000 hours and measured for mass. The mass reduction rate in Table 1 is the mass reduction amount after 1000 hours with respect to the initial mass, and the unit is mass%.
(Average coefficient of linear expansion, glass transition temperature)
Using the transfer molding apparatus, the obtained sealing resin composition was injection molded at a mold temperature of 200 ° C., an injection pressure of 9.8 MPa, and a curing time of 120 seconds to obtain a molded product of 15 mm × 4 mm × 4 mm. .

Subsequently, the obtained molded product was post-cured at 250 ° C. for 4 hours to prepare a test piece. Thereafter, the obtained test piece was subjected to measurement using a thermomechanical analyzer (manufactured by Seiko Instruments Inc., TMA100) under conditions of a measurement temperature range of 0 ° C. to 400 ° C. and a temperature increase rate of 5 ° C./min. The average linear expansion coefficient α1 in the plane direction (XY direction) in the range of the transition temperature, 50 ° C. to 70 ° C., and the average linear expansion coefficient α2 in the plane direction (XY direction) in the range of 310 ° C. to 330 ° C. were calculated. The unit of glass transition temperature is ° C. The unit of average linear expansion coefficients α1 and α2 is 10 ⁻⁶ / ° C.
(Flexural modulus)
Using a transfer molding apparatus, the sealing resin composition thus obtained was injection-molded at a mold temperature of 200 ° C., an injection pressure of 9.8 MPa, and a curing time of 120 seconds, and molded into a width of 10 mm × a thickness of 4 mm × a length of 80 mm. I got a product. Next, the obtained molded product was post-cured at 250 ° C. for 4 hours to prepare a test piece. Next, the flexural modulus at room temperature of the test piece was measured according to JIS K 6911. The unit is GPa.

  The results are summarized in Table 1 below.

As shown in Table 1, the sealing resin compositions of Examples 1 to 3 in which the content of the maleimide resin (A) was controlled were satisfactory in the temperature cycle test when applied to a semiconductor device. . In addition, it was excellent in high-temperature long-term storage characteristics, and both temperature cycle test reliability and high-temperature long-term storage characteristics were compatible.

  On the other hand, (A) Comparative Example 1 with a small proportion of maleimide resin and (A) Comparative Example 2 not containing maleimide resin were inferior in the results of the temperature cycle test and the high-temperature long-term storage characteristics as compared with each Example.

  Further, in Comparative Example 3 in which the ratio of (A) maleimide resin was large, the resin composition for sealing could not be produced because it did not melt during roll kneading.

  From the above, by obtaining the sealing resin composition in which the content of the (A) maleimide resin in the organic component was controlled, the reliability of the apparatus to which this was applied could be improved.

DESCRIPTION OF SYMBOLS 10 In-vehicle electronic control unit 12 Wiring board 14 Sealing resin 16 Electronic component 18 Connection terminal 20 Semiconductor element 30 Substrate 32 Die pad 34 Outer lead 40 Wire 50 Sealing material 60 Solder ball 100 Semiconductor device 120 Through hole

Claims (8)

(A) a maleimide resin represented by the general formula (1);
(B) a thermosetting resin;
(C) an inorganic filler;
A sealing resin composition comprising:
The content of the maleimide resin represented by (A) the general formula (1) is 30% by mass or more and 65% by mass or less with respect to the whole sealing resin composition (excluding (C) the inorganic filler). A sealing resin composition.

(In the formula (1), X ₁ is a divalent organic group having 1 to 18 carbon atoms, a group represented by the formula “—SO ₂ —”, a group represented by “—CO—”, an oxygen atom or a single atom. In addition, each R ₁ is independently a hydrogen atom, a substituent having 1 to 6 carbon atoms or an unsubstituted hydrocarbon group.) The sealing resin composition according to claim 1,
(B) The resin composition for sealing whose softening point of a thermosetting resin is a temperature lower than the softening point of said (A) maleimide resin. The sealing resin composition according to claim 1 or 2,
The (B) thermosetting resin is
(B-1) Maleimide resin (excluding those corresponding to (A) maleimide resin), (B-2) a seal selected from the group consisting of benzoxazine resin and (B-3) phenol resin Resin composition for stopping. A sealing resin composition according to any one of claims 1 to 3,
Furthermore, (D) the resin composition for sealing containing a heterocyclic compound. (A) a maleimide resin represented by the general formula (1);
(B) a thermosetting resin;
(C) an inorganic filler;
A sealing resin composition comprising:
From 310 ° C. to the average linear expansion coefficient α1 calculated in the range of 50 ° C. to 70 ° C. in the cured product obtained by curing the resin composition for sealing at 200 ° C. for 120 seconds and further cured after 250 hours at 250 ° C. A sealing resin composition having a ratio (α2 / α1) of an average linear expansion coefficient α2 calculated in a range of 340 ° C. of 1.0 or more and 7.0 or less.

(In the formula (1), X ₁ is a divalent organic group having 1 to 18 carbon atoms, a group represented by the formula “—SO ₂ —”, a group represented by “—CO—”, an oxygen atom or a single atom. In addition, each R ₁ is independently a hydrogen atom, a substituent having 1 to 6 carbon atoms or an unsubstituted hydrocarbon group.) A sealing resin composition according to any one of claims 1 to 5,
A sealing resin composition in which the glass transition temperature of a cured product obtained by curing the sealing resin composition at 200 ° C. for 120 seconds and further curing at 250 ° C. for 4 hours is from 250 ° C. to 350 ° C. A semiconductor element;
A cured product of the sealing resin composition according to any one of claims 1 to 6,
A semiconductor device comprising: The semiconductor device according to claim 7,
A semiconductor device in which the semiconductor element uses SiC, GaN, Ga ₂ O ₃ , or diamond.