JP2022027775A - Thermally conductive composition and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermally conductive composition which is small in peeling due to heat cycles when, for example, being applied to bond a semiconductor element and a substrate.

SOLUTION: A thermally conductive composition includes metal-containing particles and a thermosetting component that includes at least one selected from the group consisting of polymers, oligomers, and monomers, the metal-containing particles being sintered by heat treatment to form a particle-connected structure. A cured film, which is obtained by heating the thermally conductive composition from 30°C to 180°C at a constant rate over 60 minutes and then heating for two hours at 180°C, has a thermal conductivity λ in the thickness direction at 25°C of 25 W/m K or higher. A cured film, which is obtained by heating the thermally conductive composition from 30°C to 180°C at a constant rate over 60 minutes and then heating for two hours at 180°C, has a storage modulus E' of 10,000 MPa or less, the storage modulus being obtained by viscoelasticity measurement at 25°C, in a tension mode, and at a frequency of 1 Hz.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present invention relates to thermally conductive compositions and semiconductor devices. More specifically, the present invention relates to a semiconductor device including a thermally conductive composition and a member obtained by heat-treating the thermally conductive composition.

A technique for manufacturing a semiconductor device using a thermosetting resin composition containing metal particles is known with the intention of enhancing the heat dissipation of the semiconductor device. By including metal particles having a higher thermal conductivity than the resin in the heat-curable resin composition, the heat conductivity of the cured product can be increased.
As a specific example of application to a semiconductor device, as in Patent Documents 1 and 2 below, a semiconductor element and a substrate (support member) are bonded / bonded using a thermosetting resin composition containing metal particles. The technology to do is known.

Patent Document 1 describes a thermosetting resin composition for semiconductor adhesion, which comprises a (meth) acrylic acid ester compound, a radical initiator, silver fine particles, silver powder and a solvent (claim 1 and the like). There is also a description in this document that the bonding between the semiconductor element and the metal substrate can be realized by heating to 200 ° C. (paragraphs 0001, 0007, etc.).

Patent Document 2 describes a resin paste composition containing an epoxy resin, a curing agent, a curing accelerator, a diluent, and silver powder (Table 1 and the like). There is a description that the resin paste composition is cured at 150 ° C., and the semiconductor element and the support member can be adhered to each other by a cured product such as an epoxy resin (paragraph 0038, etc.).

Japanese Unexamined Patent Publication No. 2014-74132 Japanese Unexamined Patent Publication No. 2000-239616

Thermosetting resin compositions containing metal particles can be classified into several types according to the behavior of the metal particles during heat curing. For example, there are "sintering type" resin compositions that cause sintering by heat treatment to form a particle connection structure, and types that do not cause sintering.

According to the findings of the present inventors, when a semiconductor element and a substrate are bonded to each other with a conventional sintering type resin composition, peeling may occur due to a heat cycle (repeated heating-cooling).

The present invention has been made in view of such circumstances. One of the objects of the present invention is to provide a heat conductive composition having small peeling due to a heat cycle when applied to adhesion between a semiconductor device and a substrate, for example.

As a result of diligent studies, the present inventors have completed the inventions provided below and solved the above problems.

According to the present invention
Thermal conduction containing metal-containing particles and a thermosetting component containing at least one selected from the group consisting of polymers, oligomers and monomers, wherein the metal-containing particles undergo synterling to form a particle-connected structure by heat treatment. It is a sex composition
The heat conductive composition is heated at a constant rate from 30 ° C. to 180 ° C. for 60 minutes, and then heated at 180 ° C. for 2 hours to obtain a cured film that conducts heat in the thickness direction at 25 ° C. The rate λ is 25 W / m · K or more,
The heat conductive composition was heated at a constant rate from 30 ° C. to 180 ° C. for 60 minutes, and subsequently heated at 180 ° C. for 2 hours to obtain a cured film obtained by heating at 25 ° C., a tensile mode, and a frequency of 1 Hz. Provided is a thermally conductive composition having a storage elastic modulus E'determined by measuring viscoelasticity of 10,000 MPa or less.

Further, according to the present invention,
With the base material
A semiconductor device mounted on the substrate via an adhesive layer obtained by heat-treating the thermally conductive composition,
A semiconductor device is provided.

According to the present invention, there is provided a thermally conductive composition that is less likely to be peeled off due to a heat cycle when applied to adhesion between a semiconductor device and a substrate, for example.

It is sectional drawing which shows an example of the semiconductor device schematically. It is sectional drawing which shows an example of the semiconductor device schematically.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In all drawings, similar components are designated by the same reference numerals, and description thereof will be omitted as appropriate.
In order to avoid complication, (i) when there are a plurality of the same components in the same drawing, only one of them is coded and all of them are not coded, or (ii) especially the figure. In the second and subsequent stages, the same components as in FIG. 1 may not be designated again.
All drawings are for illustration purposes only. The shape and dimensional ratio of each member in the drawing do not necessarily correspond to the actual article.

In the present specification, the notation "a to b" in the description of the numerical range means a or more and b or less unless otherwise specified. For example, "1 to 5% by mass" means "1% by mass or more and 5% by mass or less".

In the notation of a group (atomic group) in the present specification, the notation that does not indicate whether it is substituted or unsubstituted includes both those having no substituent and those having a substituent. For example, the "alkyl group" includes not only an alkyl group having no substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).
The notation "(meth) acrylic" herein represents a concept that includes both acrylic (-CO-CH = CH ₂ ) and methacrylic (-CO-C (CH ₃ ) = CH ₂ ). The same applies to similar notations such as "(meth) acrylate".

<Thermal conductive composition>
The thermally conductive composition of the present embodiment contains metal-containing particles and a thermosetting component containing at least one selected from the group consisting of polymers, oligomers and monomers, and the metal-containing particles are sintered by heat treatment. It is a thermally conductive composition that is raised to form a particle-connected structure.
The heat conductive composition of the present embodiment is heated at a constant rate from 30 ° C. to 180 ° C. for 60 minutes, and subsequently heated at 180 ° C. for 2 hours to obtain a cured film in the thickness direction at 25 ° C. The thermal conductivity λ of is 25 W / m · K or more.
The heat conductive composition of the present embodiment was heated at a constant rate from 30 ° C. to 180 ° C. for 60 minutes, and then heated at 180 ° C. for 2 hours to obtain a cured film obtained by heating at 25 ° C. in a viscoelastic mode. The storage elastic modulus E'obtained by measuring the viscoelasticity at a frequency of 1 Hz is 10,000 MPa or less.

Hereinafter, the "thermosetting component containing at least one selected from the group consisting of polymers, oligomers and monomers" is also simply referred to as "thermosetting component".
Further, the cured film obtained by thermosetting under the above heating conditions may be referred to as "specific cured film".

The present inventors investigated the cause of peeling due to a heat cycle (repeated heating-cooling) when a sintered type thermally conductive composition was applied to adhesion.

The present inventors have found that the causes of peeling are (1) the heating temperature at which the composition is cured / the metal particles in the composition are sintered is too high, so that the cured product after cooling is thermally shrunk. It was considered that stress was generated, and (2) stress was also generated by expansion / contraction due to the heat cycle.

From the viewpoint of (1) above, the present inventors should design a composition that cures even when heated at a low temperature to some extent (when metal-containing particles are sintered, they are sintered to form a heat conduction path). I thought it was good. If the temperature required for curing / sintering of the metal-containing particles of the composition is low, the degree of heat shrinkage due to cooling after curing / sintering can be reduced, and the stress generated by the heat shrinkage can be reduced (and thus the stress generated by the heat shrinkage). This is because it was thought that the decrease in adhesive strength could be suppressed).
Further, from the viewpoint of (2) above, if the composition is designed so that the "elastic modulus" of the cured product is relatively small (so that the cured product becomes "soft" to some extent), the cured product is stressed by the heat cycle. I thought that the decrease in adhesive strength could be suppressed by absorbing the above.

Therefore, as one of the indexes for the design of the heat conductive composition, the present inventors can obtain the heat conductive composition by heating it at "180 ° C" (details of the heating conditions are as described above). The thermal conductivity λ of the cured film in the thickness direction at 25 ° C. was set. Then, I thought that if a thermally conductive composition having a sufficiently large λ was designed, the decrease in the adhesive force could be suppressed (λ is large because it correlates with the degree of sintering of the metal-containing particles). That roughly corresponds to "easy to sinter at low temperature (180 ° C)").

Further, as another index for the design of the heat conductive composition, the present inventors heat the heat conductive composition at 180 ° C. (details of the heating conditions are as described above) to obtain a cured film. , 25 ° C., tensile mode, frequency 1 Hz, and the storage elastic modulus E'obtained by measuring viscoelasticity was set. Then, I thought that if a heat conductive composition with an appropriately small E'was designed, the decrease in adhesive strength could be suppressed (if the cured product is "soft" to some extent, the cured product exerts stress due to the heat cycle. Because it seemed to be easier to absorb).

The present inventors designed a thermally conductive composition based on these two indexes. By newly designing a thermally conductive composition having λ of 25 W / m · K or more and E'of 10,000 MPa or less, it was possible to reduce the decrease in adhesive force due to the heat cycle.

In the present embodiment, a thermally conductive composition having a λ of 25 W / m · K or more and an E'of 10,000 MPa or less by appropriately selecting the type and amount of the material, the method for preparing the composition, and the like. Can be obtained. For example, by using the metal-coated resin particles described later as a part or all of the metal-containing particles, a thermally conductive composition in which λ and E'are appropriate values can be obtained. The materials that can be used and the preparation method will be explained more specifically below.

As a reminder, the present invention is not limitedly construed by the above description.

The components, physical properties, properties and the like contained in the heat conductive composition of the present embodiment will be described in detail below.

(Metal-containing particles)
The thermally conductive composition of the present embodiment contains metal-containing particles.
The metal-containing particles can typically undergo sintering (sintering) by appropriate heat treatment to form a particle-connected structure (sintering structure).

The "metal" in the metal-containing particles can be any metal. From the viewpoint of good thermal conductivity, ease of syntering, applicability to semiconductor devices, etc., the preferred metal is, for example, at least one selected from the group consisting of gold, silver, copper, nickel and tin. be. A more preferred metal is at least one selected from the group consisting of silver, gold and copper.
The metal-containing particles may contain only one type of metal or may contain two or more types of metal (that is, the metal-containing particles may be alloy-containing particles). Further, the core portion and the surface layer portion of the metal-containing particles may be composed of different kinds of metals.
In particular, the inclusion of silver-containing particles in the thermally conductive composition, in particular, the inclusion of silver particles having a relatively small particle size and a relatively large specific surface area, at a relatively low temperature (about 180 ° C.). A sintered structure is likely to be formed even by heat treatment. The preferred particle size will be described later.

The shape of the metal-containing particles is not particularly limited. The preferred shape is spherical, but non-spherical shapes such as ellipsoidal, flat, plate, flake, needle and the like may be used.
(The term "spherical" is not limited to a perfect sphere, but also includes a shape having some irregularities on the surface, etc. The same shall apply hereinafter in the present specification.)

The metal-containing particles may be (i) particles substantially composed of only metal, or (ii) particles composed of metal and non-metal components. Further, (i) and (ii) may be used in combination as the metal-containing particles.

In the present embodiment, the metal-containing particles particularly preferably include metal-coated resin particles whose surface is coated with metal. This makes it easy to prepare a thermally conductive composition having λ of 25 W / m · K or more and E'of 10,000 MPa or less.
Since the metal-coated resin particles have a metal surface and a resin inside, they are considered to have good thermal conductivity and are soft (compared to particles made of only metal). Therefore, it is considered easy to design λ and E'to appropriate values by using the metal-coated resin particles.
Usually, in order to increase λ, it is conceivable to increase the amount of metal-containing particles. However, since metals are usually "hard", if the amount of metal-containing particles is too large, the elastic modulus after sintering may become too large. Since some or all of the metal-containing particles are metal-coated resin particles, it is easy to design a thermally conductive composition having a λ of 25 W / m · K or more and an E'of 10,000 MPa or less.

In the metal-coated resin particles, a metal layer may cover at least a part of the surface of the resin particles. Of course, the entire surface of the resin particles may be covered with metal.
Specifically, in the metal-coated resin particles, the metal layer covers preferably 50% or more, more preferably 75% or more, still more preferably 90% or more of the surface of the resin particles. Particularly preferably, in the metal-coated resin particles, the metal layer covers substantially the entire surface of the resin particles.
As another viewpoint, when the metal-coated resin particles are cut in a certain cross section, it is preferable that a metal layer is confirmed all around the cross section.
As another viewpoint, the mass ratio of resin / metal in the metal-coated resin particles is, for example, 90/10 to 10/90, preferably 80/20 to 20/80, and more preferably 70/30 to 30/70. be.

The "metal" in the metal-coated resin particles is as described above. In particular, silver is preferred.
Examples of the "resin" in the metal-coated resin particles include silicone resin, (meth) acrylic resin, phenol resin, polystyrene resin, melamine resin, polyamide resin, polytetrafluoroethylene resin and the like. Of course, resins other than these may be used. Further, only one kind of resin may be used, or two or more kinds of resins may be used in combination.
From the viewpoint of elastic properties and heat resistance, the resin is preferably a silicone resin or a (meth) acrylic resin.

The silicone resin may be particles composed of organopolysiloxane obtained by polymerizing organochlorosilane such as methylchlorosilane, trimethyltrichlorosilane, and dimethyldichlorosilane. Further, a silicone resin having a structure in which organopolysiloxane is further three-dimensionally crosslinked may be used as a basic skeleton.
The (meth) acrylic resin is a resin obtained by polymerizing a monomer containing a (meth) acrylic acid ester as a main component (50% by weight or more, preferably 70% by weight or more, more preferably 90% by weight or more). be able to. Examples of the (meth) acrylic acid ester include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and lauryl (meth) acrylate. , Stearyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-propyl (meth) acrylate, chloro-2-hydroxyethyl (meth) acrylate, diethylene glycol mono (meth) acrylate, At least one compound selected from the group consisting of methoxyethyl (meth) acrylate, glycidyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate and isoboronor (meth) acrylate can be mentioned. can. Further, the monomer component of the acrylic resin may contain a small amount of other monomers. Examples of such other monomer components include styrene-based monomers. For the metal-coated (meth) acrylic resin, refer to the description in JP-A-2017-126463.
Various functional groups may be introduced into the silicone resin or the (meth) acrylic resin. The functional groups that can be introduced are not particularly limited. For example, an epoxy group, an amino group, a methoxy group, a phenyl group, a carboxyl group, a hydroxyl group, an alkyl group, a vinyl group, a mercapto group and the like can be mentioned.

The portion of the resin particles in the metal-coated resin particles may contain various additive components such as a low stress modifier. Examples of the low stress modifier include butadiene styrene rubber, butadiene acrylonitrile rubber, polyurethane rubber, polyisoprene rubber, acrylic rubber, fluororubber, liquid organopolysiloxane, liquid synthetic rubber such as liquid polybutadiene, and the like. In particular, when the portion of the resin particles contains a silicone resin, the elastic properties of the metal-coated resin particles can be made preferable by containing a low stress modifier.

The shape of the portion of the resin particles in the metal-coated resin particles is not particularly limited. The preferred shape is spherical, but irregular shapes other than spherical, such as flat, plate-shaped, and needle-shaped, may be used. When the shape of the metal-coated resin particles is formed into a spherical shape, it is preferable that the shape of the resin particles used is also spherical.

The specific gravity of the metal-coated resin particles is not particularly limited, but the lower limit is, for example, 2 or more, preferably 2.5 or more, and more preferably 3 or more. The upper limit of the specific gravity is, for example, 10 or less, preferably 9 or less, and more preferably 8 or less. Appropriate specific gravity is preferable in terms of dispersibility of the metal-coated resin particles themselves and uniformity when the metal-coated resin particles and other metal-containing particles are used in combination.

When the metal-coated resin particles are used, the proportion of the metal-coated resin particles in the entire metal-containing particles is preferably 1 to 50% by mass, more preferably 3 to 45% by mass, and further preferably 5 to 40% by mass. By appropriately adjusting this ratio, it is possible to further improve the heat dissipation while suppressing the decrease in the adhesive force due to the heat cycle.
Incidentally, when the ratio of the metal-coated resin particles in the entire metal-containing particles is not 100% by mass, the metal-containing particles other than the metal-coated resin particles are, for example, particles substantially composed of only metal.

The median diameter _D50 of the metal-containing particles (as a whole when a plurality of metal-containing particles are used in combination) is, for example, 0.001 to 1000 μm, preferably 0.01 to 100 μm, and more preferably 0.1 to 20 μm. be. By setting D ₅₀ to an appropriate value, it is easy to balance thermal conductivity, sinterability, heat cycle resistance, and the like. Further, by setting D ₅₀ to an appropriate value, it may be possible to improve the workability of coating / bonding.
The particle size distribution of the metal-containing particles (horizontal axis: particle diameter, vertical axis: frequency) may be monomodal or multimodal.

The median diameter D ₅₀ of the particles substantially composed of only metal is, for example, 0.8 μm or more, preferably 1.0 μm or more, and more preferably 1.2 μm or more. Thereby, the thermal conductivity can be further enhanced.
Further, the median diameter D ₅₀ of the particles substantially composed of only metal is, for example, 7.0 μm or less, preferably 5.0 μm or less, and more preferably 4.0 μm or less. As a result, it is possible to further improve the ease of sintering and improve the uniformity of sintering.

The median diameter D ₅₀ of the metal-coated resin particles is, for example, 0.5 μm or more, preferably 1.5 μm or more, and more preferably 2.0 μm or more. This makes it easy to set the storage elastic modulus E'to an appropriate value.
The median diameter D ₅₀ of the metal-coated resin particles is, for example, 20 μm or less, preferably 15 μm or less, and more preferably 10 μm or less. This makes it easy to sufficiently increase the thermal conductivity.

The median diameter D ₅₀ of the metal-containing particles can be determined, for example, by performing particle image measurement using a flow-type particle image analyzer FPIA (registered trademark) -3000 manufactured by Sysmex Corporation. More specifically, the particle diameter of the metal particles can be determined by measuring the volume-based median diameter in a wet manner using this device.

The proportion of metal-containing particles (in the case of using a plurality of types of metal-containing particles, the total thereof) in the entire heat conductive composition is, for example, 1 to 98% by mass, preferably 30 to 95% by mass, and more preferably 50. It is ~ 90% by mass. By setting the ratio of the metal-containing particles to 1% by mass or more, it is easy to increase the thermal conductivity. By setting the ratio of the metal-containing particles to 98% by mass or less, the workability of coating / bonding can be improved.

Among the metal-containing particles, particles substantially composed of only metal can be obtained from, for example, DOWA Hightech Co., Ltd., Fukuda Metal Foil Powder Industry Co., Ltd., and the like. Further, the metal-coated resin particles can be obtained from, for example, Mitsubishi Materials Corporation, Sekisui Chemical Co., Ltd., Sanno Co., Ltd., and the like.

(Thermosetting component)
The thermally conductive composition of the present embodiment contains at least one thermosetting component selected from the group consisting of polymers, oligomers and monomers.
The thermosetting component usually contains a group that polymerizes / crosslinks by the action of an active chemical species such as a radical, and / or a chemical structure that reacts with a curing agent described later. The thermosetting component includes, for example, one or more of an epoxy group, an oxetanyl group, a group containing an ethylenic carbon-carbon double bond, a hydroxy group, an isocyanate group, a maleimide structure, and the like.

The thermosetting component preferably contains at least one selected from the group consisting of an epoxy group-containing compound and a (meth) acryloyl group-containing compound.

The epoxy group-containing compound may be a compound having only one epoxy group in one molecule, or may be a compound having two or more epoxy groups in one molecule.

Specific examples of the epoxy group-containing compound include known epoxy resins.
Examples of the epoxy resin include bifunctional or crystalline epoxy resins such as biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, stilben type epoxy resin, and hydroquinone type epoxy resin; cresol novolac type epoxy resin, Novolak type epoxy resin such as phenol novolac type epoxy resin, naphthol novolak type epoxy resin; phenol aralkyl type epoxy resin containing phenylene skeleton, phenol aralkyl type epoxy resin containing biphenylene skeleton, phenol aralkyl type epoxy resin such as naphthol aralkyl type epoxy resin containing phenylene skeleton Resin: Trifunctional epoxy resin such as triphenol methane type epoxy resin and alkyl modified triphenol methane type epoxy resin; Modified phenol type epoxy resin such as dicyclopentadiene modified phenol type epoxy resin and terpene modified phenol type epoxy resin; Triazine nucleus Examples thereof include a heterocycle-containing epoxy resin such as a contained epoxy resin.

In addition, examples of the epoxy group-containing compound include monofunctional epoxy group-containing compounds such as 4-tert-butylphenylglycidyl ether, m, p-cresyl glycidyl ether, phenylglycidyl ether, and cresyl glycidyl ether. ..

Examples of the (meth) acryloyl group-containing compound include a monofunctional (meth) acrylic monomer having only one (meth) acrylic group in one molecule and a polyfunctional (meth) acrylic monomer having two or more (meth) acrylic groups in one molecule. Meta) Acryloyl monomer and the like can be mentioned.
The polyfunctional (meth) acrylic monomer typically comprises 2 to 6 (meth) acrylic groups in one molecule, preferably 2 to 4 (meth) acrylic groups in one molecule.

Specific examples of the monofunctional (meth) acrylic monomer include 2-phenoxyethyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, and tert-butyl (meth) acrylate. Isoamyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isodecyl (meth) acrylate, n-lauryl (meth) acrylate, n-tridecyl (meth) acrylate, n-stearyl (meth) acrylate, isostearyl (meth) acrylate , Ethoxydiethylene glycol (meth) acrylate, butoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, 2-ethylhexyldiethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, methoxydipropylene glycol (meth) acrylate , Cyclohexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, phenoxypolyethylene glycol (meth) acrylate, nonylphenol ethylene oxide-modified (meth) acrylate , Phenylphenol ethylene oxide modified (meth) acrylate, isobornyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate quaternized product, glycidyl (meth) acrylate, neopentyl Glycol (meth) acrylic acid benzoic acid ester, 1,4-cyclohexanedimethanol mono (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-Hydroxy-3-phenoxypropyl (meth) acrylate, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, 2- (Meta) acryloyloxyethyl phthalic acid, 2- (meth) acryloyloxyethyl-2-hydroxyethylphthalic acid, 2- (meth) acryloyloxyethyl acid phosphate, 2- (meth) acro Examples thereof include iroxyethyl acid phosphate.

Specific examples of the polyfunctional (meth) acrylic monomer include ethylene glycol di (meth) acrylate, trimethylolpropanetri (meth) acryloyl, propoxylated bisphenol A di (meth) acrylate, and hexane-1,6-diol bis (2-). Methyl (meth) acrylate), 4,4'-isopropyridene diphenol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,6-bis ((meth) acryloyloxy) -2,2 , 3,3,4,4,5,5-octafluorohexane, 1,4-bis ((meth) acryloyloxy) butane, 1,6-bis ((meth) acryloyloxy) hexane, triethylene glycol di ( Meta) acrylate, neopentyl glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, N, N'-di (meth) acryloylethylenediamine, N, N'-(1,2-dihydroxyethylene) bis (meth) ) Acrylate, 1,4-bis ((meth) acryloyl) piperazine and the like.

Further, as a kind of (meth) acrylic monomer, (meth) acrylamide monomer can also be mentioned. Specifically, (meth) acrylamide, diethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-dimethylmethacrylamide, N, N-diethyl (meth) acrylamide, N, N-diethyl ( Meta) acrylamide, N, N'-methylenebis (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, diacetone (meth) acrylamide, (meth) acryloylmorpholin And so on.

As the (meth) acrylic monomer, a monofunctional (meth) acrylic monomer or a polyfunctional (meth) acrylic monomer may be used alone, or a monofunctional (meth) acrylic monomer and a polyfunctional (meth) acrylic monomer may be used in combination. You may. Preferably, as the (meth) acrylic monomer, a polyfunctional acrylic monomer is used alone.
As the (meth) acrylic monomer, for example, the "light ester" series sold by Kyoeisha Chemical Co., Ltd. can be used.

The thermally conductive composition of the present embodiment may contain only one thermosetting component, or may contain two or more thermosetting components.
In the present embodiment, it is preferable that an epoxy resin and a (meth) acryloyl group-containing compound are used in combination as a thermosetting component. The ratio (mass ratio) when the epoxy resin and the (meth) acryloyl group-containing compound are used in combination is not particularly limited, but for example, epoxy resin / (meth) acryloyl group-containing compound = 95/5 to 50/50, preferably epoxy. Resin / (meth) acryloyl group-containing compound = 90/10 to 60/40.

In particular, as the epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin and the like are preferably mentioned. Further, as the (meth) acryloyl group-containing compound, a polyfunctional (meth) acrylic monomer is preferable, and a bifunctional (meth) acrylic monomer is more preferable.

The amount of the thermosetting component in the heat conductive composition of the present embodiment is, for example, 5 to 25% by mass, preferably 10 to 20% by mass, based on the total amount of the non-volatile component.

(Hardener)
The thermally conductive composition of the present embodiment may contain a curing agent.
Examples of the curing agent include those having a reactive group that reacts with a thermosetting component.
The curing agent contains, for example, a reactive group that reacts with a functional group such as an epoxy group, a maleimide group, or a hydroxy group contained in a thermosetting component.

The curing agent preferably contains a phenolic curing agent and / or an imidazole-based curing agent. These curing agents are particularly preferable when the thermosetting component contains an epoxy group.

The phenolic curing agent may be a low molecular weight compound or a high molecular weight compound (that is, a phenol resin).

Examples of the phenolic curing agent which is a low molecular weight compound include bisphenol compounds such as bisphenol A and bisphenol F (dihydroxydiphenylmethane) (phenol resins having a bisphenol F skeleton); compounds having a biphenylene skeleton such as 4,4'-biphenol. And so on.

Specifically, as the phenol resin, a novolak type phenol resin such as a phenol novolac resin, a cresol novolak resin, a bisphenol novolak resin, a phenol-biphenylnovolak resin; a polyvinylphenol; a polyfunctional phenol resin such as a triphenylmethane type phenol resin; a terpene. Modified phenol resins such as modified phenol resins and dicyclopentadiene modified phenol resins; phenol aralkyl resins having a phenylene skeleton and / or biphenylene skeleton, phenol aralkyl-type phenol resins such as naphthol aralkyl resins having phenylene and / or biphenylene skeletons, and the like. be able to.

When a curing agent is used, only one type may be used, or two or more types may be used in combination.
When the heat conductive composition of the present embodiment contains a curing agent, the amount thereof is, for example, 5 to 50 parts by mass, preferably 10 to 30 parts by mass, when the amount of the thermosetting component is 100 parts by mass. ..

(Curing accelerator)
The thermally conductive composition of the present embodiment may contain a curing accelerator.
The curing accelerator typically accelerates the reaction between the thermosetting component and the curing agent.

Specifically, as the curing accelerator, phosphorus atom-containing compounds such as organic phosphine, tetra-substituted phosphonium compound, phosphobetaine compound, adduct of phosphine compound and quinone compound, adduct of phosphonium compound and silane compound; dicyandiamide, 1 , 8-diazabicyclo [5.4.0] Undecene-7, amidines and tertiary amines such as benzyldimethylamine; nitrogen atom-containing compounds such as the amidine or the quaternary ammonium salt of the tertiary amines.

When a curing accelerator is used, only one type may be used, or two or more types may be used in combination.
When the heat conductive composition of the present embodiment contains a curing accelerator, the amount thereof is, for example, 0.1 to 10 parts by mass, preferably 0.5 to 100 parts by mass when the amount of the thermosetting component is 100 parts by mass. 5 parts by mass.

(Silane coupling agent)
The thermally conductive composition of the present embodiment may contain a silane coupling agent. As a result, the adhesive strength can be further improved.

Examples of the silane coupling agent include known silane coupling agents. Specifically, the following can be mentioned.
Vinylsilanes such as vinyltrimethoxysilane and vinyltriethoxysilane;
2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyl Epoxysilanes such as methyldiethoxysilane, 3-glycidoxypropyltriethoxysilane;
Styrylsilanes such as p-styryltrimethoxysilane;
Methylsilanes such as 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane;
Acrylic silanes such as 3- (trimethoxysilyl) propyl methacrylate, 3-acryloxypropyltrimethoxysilane;
N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, Aminosilanes such as 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, N-phenyl-γ-aminopropyltrimethoxysilane;
Isocyanurate silane;
Alkylsilane;
Ureidosilanes such as 3-ureidopropyltrialkoxysilanes;
Mercaptosilanes such as 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethoxysilane;
3-Isocyanate Silane such as propyltriethoxysilane.

When a silane coupling agent is used, only one type may be used, or two or more types may be used in combination.
When the heat conductive composition of the present embodiment contains a silane coupling agent, the amount thereof is, for example, 0.1 to 10 parts by mass, preferably 0.5 when the amount of the heat-curable component is 100 parts by mass. ~ 5 parts by mass.

(Plasticizer)
The thermally conductive composition of the present embodiment may contain a plasticizer. This makes it easy to design E'smaller. Then, it becomes easier to suppress the decrease in the adhesive force due to the heat cycle.

Specific examples of the plasticizer include a polyester compound, a silicone oil, a silicone compound such as silicone rubber, a polybutadiene compound such as a polybutadiene maleic anhydride adduct, and an acrylonitrile butadiene copolymer compound.

When a plasticizer is used, only one type may be used, or two or more types may be used in combination.
When the heat conductive composition of the present embodiment contains a plasticizer, the amount thereof is, for example, 5 to 50 parts by mass, preferably 10 to 30 parts by mass, when the amount of the thermosetting component is 100 parts by mass. ..

(Radical initiator)
The thermally conductive composition of the present embodiment may contain a radical initiator. As a result, for example, it is possible to suppress insufficient curing, sufficiently proceed with the curing reaction at a relatively low temperature (for example, 180 ° C.), and further improve the adhesive strength. It may happen.

Examples of the radical initiator include peroxides and azo compounds.

Examples of the peroxide include organic peroxides such as diacyl peroxide, dialkyl peroxide, and peroxyketal. More specifically, the following can be mentioned.
Ketone peroxides such as methyl ethyl ketone peroxide and cyclohexanone peroxide; 1,1-di (t-butylperoxy) cyclohexane, 2,2-di (4,4-di (t-butylperoxy) cyclohexyl) propane and the like. Peroxyketal;
Hydroperoxides such as p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutylhydroperoxide, cumene hydroperoxide, t-butylhydroperoxide;
To di (2-t-butylperoxyisopropyl) benzene, dicumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, t-butylcumyl peroxide, di-t- Dialkyl peroxides such as xyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexin-3, di-t-butyl peroxide;
Diacyl peroxides such as dibenzoyl peroxide and di (4-methylbenzoyl) peroxide;
Peroxydicarbonates such as di-n-propylperoxydicarbonate and diisopropylperoxydicarbonate;
Peroxyesters such as 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, t-hexylperoxybenzoate, t-butylperoxybenzoate, t-butylperoxy2-ethylhexanonate, etc. ..

Examples of the azo compound include 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis (2-cyclopropylpropionitrile), and 2,2'-azobis (2,). 4-Dimethylvaleronitrile) and the like can be mentioned.

When a radical initiator is used, only one type may be used, or two or more types may be used in combination.
When the thermally conductive composition of the present embodiment contains a radical initiator, the amount thereof is, for example, 0.1 to 10 parts by mass, preferably 0.5 to 10 parts by mass when the amount of the thermosetting component is 100 parts by mass. 5 parts by mass.

(solvent)
The thermally conductive composition of the present embodiment may contain a solvent. Thereby, for example, it is possible to adjust the fluidity of the heat conductive composition, improve the workability when forming the adhesive layer on the substrate, and the like.

The solvent is typically an organic solvent. Specific examples of the organic solvent include the following.

Methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol mono Ethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, methylmethoxybutanol, α-terpineol, β-terpineol, hexylene glycol, benzyl alcohol, 2-phenylethyl alcohol, isopalmityl alcohol, isostearyl alcohol, lauryl alcohol , Ethylene glycol, propylene glycol, butylpropylene triglycol, glycerin and other alcohols;

Acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, diacetone alcohol (4-hydroxy-4-methyl-2-pentanone), 2-octanone, isophorone (3,5,5-trimethyl-2-cyclohexene-1-one), Ketones such as diisobutyl ketone (2,6-dimethyl-4-heptanone);

Ethyl acetate, butyl acetate, diethyl phthalate, dibutyl phthalate, acetoxyethane, methyl butyrate, methyl hexanoate, methyl octanate, methyl decanoate, methyl cellosolve acetate, ethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, 1,2- Esters such as diacetoxyethane, tributyl phosphate, tricresyl phosphate, tripentyl phosphate, etc.;

Tetrahydrofuran, dipropyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, propylene glycol dimethyl ether, ethoxyethyl ether, 1,2-bis (2-diethoxy) ethane, 1,2-bis (2-methoxyethoxy) ) Ethers such as ethane;

Ester ethers such as 2- (2 butoxyethoxy) ethane acetate;
Ether alcohols such as 2- (2-methoxyethoxy) ethanol;
Hydrocarbons such as toluene, xylene, n-paraffin, isoparaffin, dodecylbenzene, turpentine oil, kerosene, and light oil;
Nitriles such as acetonitrile or propionitrile;
Amides such as acetamide, N, N-dimethylformamide;
Silicone oils such as low molecular weight volatile silicone oils and volatile organic modified silicone oils.

When a solvent is used, only one kind of solvent may be used, or two or more kinds of solvents may be used in combination.
When a solvent is used, the amount thereof is not particularly limited. The amount used may be appropriately adjusted based on the desired fluidity and the like. As an example, the solvent is used in an amount such that the concentration of the non-volatile component of the thermally conductive composition is 50 to 90% by mass.

(Characteristics of composition)
The thermally conductive composition of the present embodiment is preferably in the form of a paste at 20 ° C. That is, the thermally conductive composition of the present embodiment can be preferably applied to a substrate or the like at 20 ° C. like glue. As a result, the thermally conductive composition of the present embodiment can be preferably used as an adhesive for semiconductor devices and the like.
Of course, depending on the process to be applied and the like, the thermally conductive composition of the present embodiment may be in the form of a varnish having a relatively low viscosity.

(Supplementary information about λ)
As described above, the thermal conductivity λ of the specified cured film in the thickness direction at 25 ° C. is 25 W / m · K or more. λ is preferably 30 W / m · K or more, more preferably 50 W / m · K or more. A large value of λ itself means that the heat dissipation is good. That is, a large value of λ means that the thermally conductive composition of the present embodiment is preferably applicable to a semiconductor device.
From a realistic design point of view, λ is, for example, 200 W / m · K or less, preferably 150 W / m · K or less.

(Supplement about E')
As described above, the storage elastic modulus E'obtained by measuring the viscoelasticity of the specific cured film at 25 ° C., a tensile mode, and a frequency of 1 Hz is 10000 MPa or less. E'is preferably 8000 MPa or less, more preferably 6000 MPa or less. When the value of E'is moderately small, it becomes easier to absorb the stress due to the heat cycle.
On the other hand, E'is preferably 500 MPa or more, more preferably 1000 MPa or more. When the value of E'is moderately large, the mechanical strength of the cured product is enhanced. That is, damage due to physical impact or the like is suppressed.

<Semiconductor device>
A semiconductor device can be manufactured using the above-mentioned thermally conductive composition. For example, a semiconductor device can be manufactured by using the above-mentioned heat conductive composition as an "adhesive" between a base material and a semiconductor element.
In other words, the semiconductor device of the present embodiment includes, for example, a base material and a semiconductor element mounted on the base material via an adhesive layer obtained by heat-treating the above-mentioned heat conductive composition.
In the semiconductor device of the present embodiment, the adhesiveness of the adhesive layer is unlikely to decrease even with a heat cycle. That is, the reliability of the semiconductor device of this embodiment is high.

Examples of the semiconductor element include ICs, LSIs, power semiconductor elements (power semiconductors), and various other elements.
Examples of the substrate include various semiconductor wafers, lead frames, BGA substrates, mounting substrates, heat spreaders, heat sinks, and the like.

Hereinafter, an example of a semiconductor device will be described with reference to the drawings.
FIG. 1 is a cross-sectional view showing an example of a semiconductor device.
The semiconductor device 100 includes a base material 30 and a semiconductor element 20 mounted on the base material 30 via an adhesive layer 10 (diatack material) which is a heat-treated body of a heat-conducting composition.
The semiconductor element 20 and the base material 30 are electrically connected via, for example, a bonding wire 40 or the like. Further, the semiconductor element 20 is sealed with, for example, a sealing resin 50.

The thickness of the adhesive layer 10 is preferably 5 μm or more, more preferably 10 μm or more, still more preferably 20 μm or more. As a result, the stress absorption capacity of the heat conductive composition can be improved, and the heat cycle resistance can be improved.
The thickness of the adhesive layer 10 is, for example, 100 μm or less, preferably 50 μm or less.

In FIG. 1, the base material 30 is, for example, a lead frame. In this case, the semiconductor element 20 is mounted on the die pad 32 or the base material 30 via the adhesive layer 10. Further, the semiconductor element 20 is electrically connected to the outer lead 34 (base material 30) via, for example, a bonding wire 40. The base material 30 which is a lead frame is composed of, for example, a 42 alloy, a Cu frame, or the like.

The base material 30 may be an organic substrate or a ceramic substrate. Examples of the organic substrate include those made of an epoxy resin, a cyanate resin, a maleimide resin, or the like.
The surface of the base material 30 may be coated with a metal such as silver or gold. This improves the adhesiveness between the adhesive layer 10 and the base material 30.

FIG. 2 is a cross-sectional view showing an example of a semiconductor device 100 different from that of FIG.
In the semiconductor device 100 of FIG. 2, the base material 30 is, for example, an interposer. Of the base material 30 that is an interposer, for example, a plurality of solder balls 52 are formed on the surface opposite to one surface on which the semiconductor element 20 is mounted. In this case, the semiconductor device 100 is connected to another wiring board via the solder balls 52.

An example of a method for manufacturing a semiconductor device will be described.
First, the heat conductive composition is applied onto the base material 30, and then the semiconductor element 20 is arranged on the heat conductive composition. That is, the base material 30, the heat conductive composition, and the semiconductor element 20 are laminated in this order.
The method of applying the thermally conductive composition is not particularly limited. Specific examples thereof include a dispensing method, a printing method, and an inkjet method.
The thermally conductive composition is then thermoset. The thermosetting is preferably performed by pre-curing and post-curing. By thermosetting, the thermally conductive composition becomes a heat-treated body (cured product). By thermal curing (heat treatment), the metal-containing particles in the thermally conductive composition are aggregated, and a structure in which the interface between the plurality of metal-containing particles disappears is formed in the adhesive layer 10. As a result, the base material 30 and the semiconductor element 20 are adhered to each other via the adhesive layer 10. Next, the semiconductor element 20 and the base material 30 are electrically connected using the bonding wire 40. Next, the semiconductor element 20 is sealed with the sealing resin 50. In this way, the semiconductor device can be manufactured.

Although the embodiments of the present invention have been described above, these are examples of the present invention, and various configurations other than the above can be adopted. Further, the present invention is not limited to the above-described embodiment, and modifications, improvements, and the like to the extent that the object of the present invention can be achieved are included in the present invention.

Embodiments of the present invention will be described in detail based on Examples and Comparative Examples. The present invention is not limited to the examples.

<Preparation of thermally conductive composition>
First, each raw material component was mixed according to the blending amount shown in Table 1 below to obtain a varnish.
Next, the obtained varnish, solvent and metal-containing particles (including metal-coated resin particles) were blended according to the blending amounts shown in Table 1 below, and kneaded at room temperature with a three-roll mill. As a result, a paste-like heat conductive composition was prepared.

The information on the raw material components in Table 1 is shown below.

(Thermosetting component)
Epoxy resin 1: Bisphenol F type liquid epoxy resin (manufactured by Nippon Kayaku Co., Ltd., RE-303S)
-Acrylic monomer 1: (meth) acrylic monomer (ethylene glycol dimethacrylate, manufactured by Kyoei Kagaku Co., Ltd., light ester EG)
-Acrylic monomer 2: (meth) acrylic monomer (phenoxyethyl methacrylate, manufactured by Kyoei Kagaku Co., Ltd., light ester PO)
Acrylic monomer 3: (meth) acrylic monomer (1,4-cyclohexanedimethanol monoacrylate, manufactured by Mitsubishi Chemical Corporation, CHDMMA)

(Hardener)
-Curing agent 1: Phenol resin having a bisphenol F skeleton (solid at room temperature 25 ° C, manufactured by DIC, DIC-BPF)

(Acrylic particles)
-Acrylic particles 1: Isobutyl = methacrylate-methyl = methacrylate polymer (manufactured by Sekisui Plastics Co., Ltd., IBM-2, particle size 0.1-0.8 mm)

(Plasticizer)
-Plasticizer 1: Allyl resin (manufactured by Kanto Chemical Co., Inc., polymer of 1,2-cyclohexanedicarboxylic acid bis (2-propenyl) and propane-1,2-diol, polyester compound with the following chemical structure, R is methyl Base)

(Silane coupling agent)
-Silane coupling agent 1: 3- (trimethoxysilyl) propyl methacrylate (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-503P)
-Silane coupling agent 2: 3-glycidyloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-403E)

(Curing accelerator)
-Imidazole curing agent 1: 2-phenyl-1H-imidazole-4,5-dimethanol (manufactured by Shikoku Chemicals Corporation, 2PHZ-PW)

(Polymer initiator)
-Radical polymerization initiator 1: Dicumyl peroxide (manufactured by Kayaku Akzo, Percadox BC)

(solvent)
-Solvent 1: Butyl propylene triglycol (BFTG)

(Metal-containing particles)
-Silver particles 1: Silver powder (manufactured by DOWA Hightech, AG-DSB-114, spherical, _D50 : 1 μm)
-Silver particles 2: Silver powder (manufactured by Fukuda Metal Foil Powder Industry Co., Ltd., HKD-16, flake-shaped, D ₅₀ : 2 μm)
-Silver-coated resin particles 1: Silver-plated silicone resin particles (manufactured by Mitsubishi Materials, heat-resistant / surface-treated 10 μm product, spherical shape, D ₅₀ : 10 μm, specific gravity: 2.3, silver weight ratio 50 wt%, resin weight ratio 50wt%)
-Silver-coated resin particles 2: Silver-plated acrylic resin particles (manufactured by Sanno Co., Ltd., SANSILVER-8D, spherical shape, D ₅₀ : 8 μm, monodisperse particles, specific gravity: 2.4, silver weight ratio 50 wt%, resin weight Ratio 50 wt%)

<Measurement of thermal conductivity λ in the thickness direction at 25 ° C>
The obtained thermally conductive composition was applied onto a Teflon plate, heated from 30 ° C. to 180 ° C. over 60 minutes, and then heat-treated at 180 ° C. for 120 minutes. As a result, a heat-treated body of a thermally conductive composition having a thickness of 1 mm was obtained (“Teflon” is a registered trademark of fluororesin).
Next, the thermal diffusivity α in the thickness direction of the heat-treated body was measured by a laser flash method. The measurement temperature was 25 ° C.
In addition, the specific heat Cp was measured by differential scanning calorimetry (DSC) measurement.
Furthermore, the density ρ was measured according to JIS K 6911.
Using these values, the thermal conductivity λ was calculated based on the following equation.
Thermal conductivity λ [W / (m · K)] = α [m ² / sec] × Cp [J / kg · K] × ρ [g / cm ³ ]

<Measurement of storage elastic modulus E'at 25 ° C>
The obtained thermally conductive composition was applied onto a Teflon plate, heated from 30 ° C. to 180 ° C. over 60 minutes, and then heat-treated at 180 ° C. for 120 minutes. As a result, a heat-treated body having a heat-conducting composition having a thickness of 0.3 mm was obtained. The obtained heat-treated body was peeled off from the Teflon plate and set in a measuring device (DMS6100 manufactured by Hitachi High-Tech Science Co., Ltd.) in a tensile mode. , Dynamic mechanical analysis (DMA) was performed at a frequency of 1 Hz. Thereby, the storage elastic modulus E'(MPa) at 25 ° C. was measured.

<Confirmation of sintering>
The heat-treated body (cured film) used for the above-mentioned measurement of λ and E'was polished with an automatic polishing machine, and the polished surface was observed with an SEM (scanning electron microscope).
As a result of observation, it was confirmed that in all the heat-treated bodies prepared by using the compositions of Examples 1 to 3, the metal-containing particles were sintered by heating and a connected structure of the metal-containing particles was formed. In particular, in the linked structure of the metal-containing particles, the particles substantially composed of only metal and the metal on the surface of the metal-coated resin particles are sintered to form a linked structure.

<Heat cycle test / evaluation of peeling>
A heat conductive composition is applied on a surface silver-plated substrate to form a coating film, and a 3.5 × 3.5 mm silicon chip (only Comparative Example 2 is surface silver-plated, and the others are otherwise). No plating) was placed. The reason why the surface silver-plated silicon chip was used in Comparative Example 2 is that the silicon chip did not bond to the substrate at all in the case of no plating.
Then, the temperature was raised from 30 ° C. to 180 ° C. over 60 minutes, and then heat treatment was performed at 180 ° C. for 120 minutes. As described above, the heat conductive composition was cured, and the silicon chip was bonded to the substrate.
The bonded silicon chip / substrate was sealed with the sealing material EME-G700ML-C (manufactured by Sumitomo Bakelite). This was used as a sample for the temperature cycle test.

The sample was placed in a high temperature and high humidity bath at 85 ° C./60% RH, treated for 168 hours, and then subjected to a reflow treatment at 260 ° C.
The sample after the reflow treatment was put into a temperature cycle tester TSA-72ES (manufactured by Espec), and (i) 150 ° C./10 minutes, (ii) 25 ° C./10 minutes, (iii) -65 ° C./10 minutes, (Iv) 2000 cycles were performed with 25 ° C./10 minutes as one cycle.
After that, the presence or absence of peeling was confirmed by SAT (ultrasonic flaw detection). Those without peeling were evaluated as ◯ (good), and those with peeling were evaluated as × (poor).

Table 1 summarizes the composition of the thermally conductive composition, the thermal conductivity λ, the storage elastic modulus E', and the results of the heat cycle test. In Table 1, the unit of the amount of each component is a mass part.

As shown in Table 1, in the heat cycle test using the thermally conductive compositions of Examples 1 to 3 (λ is 25 W / m · K or more and E'is 10,000 MPa or less), peeling is performed. It did not occur.
On the other hand, in the heat cycle test using the heat conductive inhibitor (E'is more than 10,000 MPa) of Comparative Examples 1 and 2, peeling occurred.

This application claims priority on the basis of Japanese Application Japanese Patent Application No. 2019-161766 filed on September 5, 2019, and incorporates all of its disclosures herein.

100 Semiconductor device 10 Adhesive layer 20 Semiconductor element 30 Base material 32 Die pad 34 Outer lead 40 Bonding wire 50 Encapsulating resin 52 Solder ball

According to the present invention
Thermal conduction containing metal-containing particles and a thermosetting component containing at least one selected from the group consisting of polymers, oligomers and monomers, wherein the metal-containing particles undergo synterling to form a particle-connected structure by heat treatment. It is a sex composition
The metal-containing particles include metal-coated resin particles whose surface is coated with at least one metal selected from the group consisting of silver, copper, nickel and tin.
The heat conductive composition is heated at a constant rate from 30 ° C. to 180 ° C. for 60 minutes, and then heated at 180 ° C. for 2 hours to obtain a cured film that conducts heat in the thickness direction at 25 ° C. The rate λ is 25 W / m · K or more,
The heat conductive composition was heated at a constant rate from 30 ° C. to 180 ° C. for 60 minutes, and subsequently heated at 180 ° C. for 2 hours to obtain a cured film obtained by heating at 25 ° C., a tensile mode, and a frequency of 1 Hz. Provided is a thermally conductive composition having a storage elastic modulus E'determined by measuring viscoelasticity of 10,000 MPa or less.

Although the embodiments of the present invention have been described above, these are examples of the present invention, and various configurations other than the above can be adopted. Further, the present invention is not limited to the above-described embodiment, and modifications, improvements, and the like to the extent that the object of the present invention can be achieved are included in the present invention.
Hereinafter, an example of the reference form will be added.
1. 1.
Thermal conduction containing metal-containing particles and a thermosetting component containing at least one selected from the group consisting of polymers, oligomers and monomers, wherein the metal-containing particles undergo synterling to form a particle-connected structure by heat treatment. It is a sex composition
The heat conductive composition is heated at a constant rate from 30 ° C. to 180 ° C. for 60 minutes, and then heated at 180 ° C. for 2 hours to obtain a cured film that conducts heat in the thickness direction at 25 ° C. The rate λ is 25 W / m · K or more,
The heat conductive composition was heated at a constant rate from 30 ° C. to 180 ° C. for 60 minutes, and subsequently heated at 180 ° C. for 2 hours to obtain a cured film obtained by heating at 25 ° C., a tensile mode, and a frequency of 1 Hz. A thermally conductive composition having a storage elastic modulus E'determined by measuring viscoelasticity of 10,000 MPa or less.
2. 2.
1. 1. The thermally conductive composition according to the above.
The metal-containing particles are thermally conductive compositions containing particles containing at least one selected from the group consisting of silver, gold and copper.
3. 3.
1. 1. Or 2. The thermally conductive composition according to the above.
The metal-containing particles are a thermally conductive composition containing metal-coated resin particles whose surface is coated with metal.
4.
1. 1. ~ 3. The thermally conductive composition according to any one of the above.
The thermosetting component comprises at least one selected from the group consisting of an epoxy group-containing compound and a (meth) acryloyl group-containing compound.
5.
1. 1. ~ 4. The thermally conductive composition according to any one of the above.
A thermally conductive composition further comprising a curing agent.
6.
5. The thermally conductive composition according to the above.
The curing agent is a thermally conductive composition containing a phenol-based curing agent and / or an imidazole-based curing agent.
7.
1. 1. ~ 6. The thermally conductive composition according to any one of the above.
A thermally conductive composition further comprising a silane coupling agent.
8.
1. 1. ~ 7. The thermally conductive composition according to any one of the above.
A thermally conductive composition further comprising a plasticizer.
9.
1. 1. ~ 8. The thermally conductive composition according to any one of the above.
A thermally conductive composition further comprising a radical initiator.
10.
1. 1. ~ 9. The thermally conductive composition according to any one of the above.
A thermally conductive composition further comprising a solvent.
11.
1. 1. ~ 10. The thermally conductive composition according to any one of the above.
A thermally conductive composition that is in the form of a paste at 25 ° C.
12.
With the base material
1. 1. ~ 11. A semiconductor device mounted on the substrate via an adhesive layer obtained by heat-treating the thermally conductive composition according to any one of the above.
A semiconductor device.

Claims (12)

Thermal conduction containing metal-containing particles and a thermosetting component containing at least one selected from the group consisting of polymers, oligomers and monomers, wherein the metal-containing particles undergo syntaration by heat treatment to form a particle-connected structure. It is a sex composition
The heat conductive composition is heated at a constant rate from 30 ° C. to 180 ° C. for 60 minutes, and then heated at 180 ° C. for 2 hours to obtain a cured film that conducts heat in the thickness direction at 25 ° C. The rate λ is 25 W / m · K or more,
The heat conductive composition was heated at a constant rate from 30 ° C. to 180 ° C. for 60 minutes, and subsequently heated at 180 ° C. for 2 hours to obtain a cured film obtained by heating at 25 ° C., a tensile mode, and a frequency of 1 Hz. A thermally conductive composition having a storage elastic modulus E'determined by measuring viscoelasticity of 10,000 MPa or less. The heat conductive composition according to claim 1.
The metal-containing particles are thermally conductive compositions containing particles containing at least one selected from the group consisting of silver, gold and copper. The heat conductive composition according to claim 1 or 2.
The metal-containing particles are a thermally conductive composition containing metal-coated resin particles whose surfaces are coated with metal. The thermally conductive composition according to any one of claims 1 to 3.
The thermosetting component comprises at least one selected from the group consisting of an epoxy group-containing compound and a (meth) acryloyl group-containing compound. The thermally conductive composition according to any one of claims 1 to 4.
A thermally conductive composition further comprising a curing agent. The heat conductive composition according to claim 5.
The curing agent is a thermally conductive composition containing a phenol-based curing agent and / or an imidazole-based curing agent. The thermally conductive composition according to any one of claims 1 to 6.
A thermally conductive composition further comprising a silane coupling agent. The thermally conductive composition according to any one of claims 1 to 7.
A thermally conductive composition further comprising a plasticizer. The thermally conductive composition according to any one of claims 1 to 8.
A thermally conductive composition further comprising a radical initiator. The thermally conductive composition according to any one of claims 1 to 9.
A thermally conductive composition further comprising a solvent. The thermally conductive composition according to any one of claims 1 to 10.
A thermally conductive composition that is in the form of a paste at 25 ° C. With the base material
A semiconductor device mounted on the substrate via an adhesive layer obtained by heat-treating the thermally conductive composition according to any one of claims 1 to 11.
A semiconductor device.

Images