JP7279802B2 - PASTE RESIN COMPOSITION FOR HIGH THERMAL CONDUCTIVE MATERIAL, HIGH THERMAL CONDUCTIVE MATERIAL, AND SEMICONDUCTOR DEVICE - Google Patents

Description

TECHNICAL FIELD The present invention relates to a paste resin composition, a highly thermally conductive material, and a semiconductor device.

2. Description of the Related Art Techniques for manufacturing a semiconductor device using a thermosetting resin composition containing metal particles are known, with the intention of improving the heat dissipation of the semiconductor device. By including metal particles having a higher thermal conductivity than the resin in the thermosetting resin composition, the thermal conductivity of the cured product can be increased.

As a specific example of application to a semiconductor device, a thermosetting resin composition containing metal particles is used to adhere/join a semiconductor element and a substrate (supporting member), as in Patent Documents 1 and 2 below. technology is known.

Patent Document 1 discloses a thermosetting resin composition for bonding semiconductors containing a (meth)acrylic acid ester compound having a predetermined structure, a radical initiator, fine silver particles, silver powder, and a solvent; is disclosed. This document describes that connection reliability against temperature cycles after mounting can be improved (paragraph 0011).

Patent Document 2 discloses a resin paste composition containing an imide acrylate compound, a radical initiator, a filler, and a liquid rubber component, and a semiconductor device in which a semiconductor element and a substrate are bonded with the composition. This document describes that the generation of chip cracks and chip warpage can be suppressed by reducing the stress of the resin paste composition (paragraph 0003).

JP 2014-74132 A JP-A-2000-239616

However, a semiconductor device in which a semiconductor element and a base material are bonded with the resin compositions described in Patent Documents 1 and 2 may not exhibit good conductivity over a long period of time, and long-term reliability cannot be improved. There was room.

The present inventors found that by using a (meth)acryloyl group-containing compound having a predetermined structure, a semiconductor device exhibits good conductivity over a long period of time and is excellent in long-term reliability. completed.

（一般式（１）中、Ｒは水素原子または炭素数１～３のアルキル基を示し、複数存在するＲは同一でも異なっていてもよい。Ｘは水素原子、ハロゲン原子、アミノ基、シアノ基、メルカプト基、カルボキシル基、炭素数１～３のアルキル基、または炭素数１～３のアルコキシ基を示し、複数存在するＸは同一でも異なっていてもよい。ｍは２～１０の整数を示す。ｎは８以上３０以下の整数を示す。）
本発明によれば、前記ペースト状樹脂組成物を焼結して得られる高熱伝導性材料が提供される。
本発明によれば、基材と、前記基材上に接着層を介して搭載された半導体素子と、を備え、前記接着層は、前記ペースト状樹脂組成物を焼結してなる、半導体装置が提供される。 The present invention can be shown below.
According to the invention,
(A) a (meth)acryloyl group-containing compound containing at least one selected from compounds represented by the following general formula (1);
(B) metal-containing particles, including silver-containing particles or copper-containing particles;
A paste-like resin composition is provided.

(In the general formula (1), R represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and multiple R may be the same or different. X is a hydrogen atom, a halogen atom, an amino group, a cyano group , a mercapto group, a carboxyl group, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and multiple X may be the same or different, m is an integer of 2 to 10 .n represents an integer of 8 or more and 30 or less.)
According to the present invention, there is provided a highly thermally conductive material obtained by sintering the paste resin composition.
According to the present invention, a semiconductor device comprising a substrate and a semiconductor element mounted on the substrate via an adhesive layer, wherein the adhesive layer is formed by sintering the paste resin composition. is provided.

INDUSTRIAL APPLICABILITY According to the present invention, a paste-like resin composition that exhibits good conductivity over a long period of time and can provide a semiconductor device with excellent long-term reliability by applying it to the bonding of a semiconductor element and a base material. can be provided.

1 is a cross-sectional view schematically showing an example of a semiconductor device; FIG. 1 is a cross-sectional view schematically showing an example of a semiconductor device; FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. In addition, in all the drawings, the same constituent elements are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. In addition, "~" represents "more than" to "less than" unless otherwise specified.

The paste-like resin composition of the present embodiment includes (A) a (meth)acryloyl group-containing compound having at least two functionalities and having two or more repeating units of a linear or branched oxyalkylene group, and (B) and metal-containing particles comprising silver or copper particles.

[(Meth)acryloyl group-containing compound (A)]
As the (meth)acryloyl group-containing compound (A), any compound having two or more functional (meth)acryloyl groups and having two or more repeating units of a linear or branched oxyalkylene group can be used. It can be used without particular limitation as long as the effect can be exhibited.

In the present embodiment, by using a paste-like resin composition containing the (meth)acryloyl group-containing compound (A) having the structure, the material obtained by sintering the composition has a reduced stress and toughness. It is also excellent (breaking energy is high and it is difficult to break). Therefore, the semiconductor device in which the semiconductor element and the base material are bonded by the paste resin composition of the present embodiment suppresses peeling of the bonding portion, etc., exhibits good conductivity over a long period of time, and has long-term reliability. It is considered to be superior to

The number of repeating units of the oxyalkylene group can be 2 or more, preferably 4 or more, more preferably 4 to 30, particularly preferably 8 to 30, from the viewpoint of the effects of the present invention.

The oxyalkylene group is a linear or branched oxyalkylene group having 2 to 10 carbon atoms, preferably a linear or branched oxyalkylene group having 2 to 8 carbon atoms, more preferably a linear or branched oxyalkylene group having 2 to 8 carbon atoms. 5 oxyalkylene groups can be mentioned.
In the present embodiment, the (meth)acryloyl group-containing compound (A) preferably contains at least one compound selected from compounds represented by the following general formula (1).

In general formula (1), R represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and multiple R's may be the same or different.
X represents a hydrogen atom, a halogen atom, a hydroxyl group, an amino group, a cyano group, a mercapto group, a carboxyl group, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, preferably a hydrogen atom or a carbon number 1 to 3 alkyl groups. Multiple X's may be the same or different.
m can represent an integer of 2-10, preferably an integer of 2-8, more preferably an integer of 2-5.
n represents an integer of 4 or more and 30 or less, preferably an integer of 8 or more and 30 or less.

(Meth)acryloyl group-containing compound (A) includes diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, polyethylene glycol #200 di(meth)acrylate (n:4), polyethylene glycol # 400 di(meth)acrylate (n:9), polyethylene glycol #600 di(meth)acrylate (n:14), polyethylene glycol #1000 di(meth)acrylate (n:23), and the like.

The (meth)acryloyl group-containing compound (A) is 0.1 to 15% by weight or less, preferably 0.5 to 10% by weight, based on the total nonvolatile components of the paste resin composition, from the viewpoint of the effects of the present invention. , more preferably in an amount of 1.0 to 8% by weight.

In addition to the (meth)acryloyl group-containing compound (A) within a range that does not affect the effects of the present invention, a (meth)acryloyl group-containing monofunctional (meth)acryloyl monomer having only one (meth)acryloyl group in one molecule (meth) ) A (meth)acryloyl group-containing compound other than the acryloyl group-containing compound (A) can also be included.

[Metal-containing particles (B)]
The metal-containing particles (B) can be sintered by appropriate heat treatment to form a particle connecting structure (sintering structure).
Metal-containing particles (B) can include silver-containing particles or copper-containing particles.

In particular, the inclusion of silver-containing particles in the paste-like resin composition, particularly the inclusion of silver particles having a relatively small particle size and a relatively large specific surface area, allows A sintered structure is likely to be formed even by heat treatment. A preferred particle size will be described later.

The shape of the metal-containing particles (B) is not particularly limited. The preferred shape is spherical, but non-spherical shapes such as ellipsoidal, flattened, plate-like, flake-like, and needle-like are also possible.
(“Spherical” is not limited to a perfect sphere, but also includes a shape with a slight unevenness on the surface, etc. The same shall apply hereinafter in this specification.)

The metal-containing particles (B) may be (i) particles consisting essentially of a metal, or (ii) particles consisting of a metal and a component other than a metal. Moreover, (i) and (ii) may be used together as the metal-containing particles.

In this embodiment, the metal-containing particles (B) particularly preferably include metal-coated resin particles in which the surfaces of resin particles are coated with a metal. As a result, it is possible to prepare a paste-like resin composition from which a cured product having excellent thermal conductivity and excellent storage elastic modulus can be obtained.

Since the metal-coated resin particles have a metal surface and a resin inside, they have good thermal conductivity and are softer than particles made only of metal. Therefore, by using the metal-coated resin particles, the thermal conductivity and the storage elastic modulus can be easily designed to appropriate values.

Generally, in order to increase the thermal conductivity, it is conceivable to increase the amount of metal-containing particles. However, since metals are generally "hard", too much metal-containing particles may result in too high a modulus after sintering. By using metal-coated resin particles for part or all of the metal-containing particles, it is possible to easily design a paste-like resin composition from which a cured product having desired thermal conductivity and storage elastic modulus can be obtained.

In the metal-coated resin particles, it is sufficient that at least a part of the surface of the resin particles is covered with a metal layer. Of course, the metal may cover the entire surface of the resin particles.

Specifically, in the metal-coated resin particles, the metal layer preferably covers 50% or more, more preferably 75% or more, and 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.
From another point of view, when the metal-coated resin particles are cut along a certain cross section, it is preferable that the metal layer is observed all around the cross section.

As another aspect, 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, more preferably 70/30 to 30/70. be.

The “metal” in the metal-coated resin particles is as described above. Silver is particularly preferred.
Examples of the "resin" in the metal-coated resin particles include silicone resins, (meth)acrylic resins, phenol resins, polystyrene resins, melamine resins, polyamide resins, and polytetrafluoroethylene resins. Of course, resins other than these may be used. Moreover, only one resin may be used, or two or more 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 organochlorosilanes such as methylchlorosilane, trimethyltrichlorosilane and dimethyldichlorosilane. Alternatively, a silicone resin having a basic skeleton structure obtained by further three-dimensionally cross-linking an organopolysiloxane may be used.

The (meth)acrylic resin contains 50% by weight or more, preferably 70% by weight or more, more preferably 90% by weight or more of a resin obtained by polymerizing a monomer containing a (meth)acrylic acid ester as a main component. can be done. (Meth)acrylic acid esters, for example, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 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 isoboronol (meth)acrylate can be mentioned. can. Further, the monomer component of the acrylic resin may contain a small amount of other monomers. Such other monomer components include, for example, styrenic monomers. For the metal-coated (meth)acrylic resin, see also the description in JP-A-2017-126463.

Various functional groups may be introduced into the silicone resin or (meth)acrylic resin. Functional groups that can be introduced are not particularly limited. Examples thereof include epoxy group, amino group, methoxy group, phenyl group, carboxyl group, hydroxyl group, alkyl group, vinyl group and mercapto group.

The resin particle portion of the metal-coated resin particles may contain various additive components such as low stress modifiers. Examples of low-stress modifiers include liquid synthetic rubbers such as butadiene styrene rubber, butadiene acrylonitrile rubber, polyurethane rubber, polyisoprene rubber, acrylic rubber, fluorine rubber, liquid organopolysiloxane, and liquid polybutadiene. In particular, when the resin particle portion contains a silicone resin, the inclusion of a low-stress modifier can make the elastic properties of the metal-coated resin particles preferable.

The shape of the resin particle portion in the metal-coated resin particles is not particularly limited. A preferred shape is spherical, but non-spherical shapes such as flat, plate-like, and needle-like may also be used. When the shape of the metal-coated resin particles is spherical, the shape of the resin particles used is also preferably 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. Further, the upper limit of the specific gravity is, for example, 10 or less, preferably 9 or less, 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 together.

When metal-coated resin particles are used, the proportion of the metal-coated resin particles in the total metal-containing particles (B) is preferably 1 to 50% by mass, more preferably 3 to 45% by mass, and still more preferably 5 to 40% by mass. is. By appropriately adjusting this ratio, it is possible to further improve heat dissipation while suppressing a decrease in adhesive strength due to heat cycles.

Incidentally, when the proportion of the metal-coated resin particles in the entire metal-containing particles (B) is not 100% by mass, the metal-containing particles other than the metal-coated resin particles are, for example, particles consisting essentially of metal.

The median diameter _D50 of the metal-containing particles (B) (as a whole when multiple types of metal-containing particles are used together) is, for example, 0.001 to 1000 μm, preferably 0.01 to 100 μm, more preferably 0.1. ~20 μm. By setting _D50 to an appropriate value, it is easy to balance thermal conductivity, sinterability, resistance to heat cycles, and the like. Also, by setting the _D50 to an appropriate value, it may be possible to improve the workability of application/adhesion.
The particle size distribution (horizontal axis: particle size, vertical axis: frequency) of the metal-containing particles may be unimodal or multimodal.

The median diameter _D50 of the particles consisting essentially of metal is, for example, 0.8 μm or more, preferably 1.0 μm or more, and more preferably 1.2 μm or more. Thereby, heat conductivity can be improved more.

In addition, the median diameter _D50 of the particles consisting essentially of metal is, for example, 7.0 μm or less, preferably 5.0 μm or less, 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 _D50 of the metal-containing particles (B) 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.

In addition, the median diameter _D50 of the metal-containing particles (B) is, for example, 20 μm or less, preferably 15 μm or less, 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 (B) can be obtained, 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-containing particles (B) can be determined by measuring the volume-based median diameter in a wet manner using this device.

The proportion of the metal-containing particles (B) in the entire paste-like resin composition (the total of them when using multiple types of metal-containing particles) is, for example, 1 to 98% by mass, preferably 30 to 95% by mass, or more. It is preferably 50 to 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 (B) to 98% by mass or less, the workability of coating/adhesion can be improved.

Among the metal-containing particles (B), particles consisting essentially of metal can be obtained from, for example, DOWA Hi-Tech Co., Ltd., Fukuda Metal Foil & Powder Co., Ltd., and the like. Also, metal-coated resin particles can be obtained from, for example, Mitsubishi Materials Corporation, Sekisui Chemical Co., Ltd., Sanno Co., Ltd., and the like.

[Thermosetting resin (C)]
The paste resin composition of the present embodiment can further contain a thermosetting resin (C). In this embodiment, the thermosetting resin (C) does not contain the (meth)acryloyl group-containing compound (A).

The thermosetting resin (C) usually contains groups that polymerize/crosslink under the action of active chemical species such as radicals, and/or chemical structures that react with the curing agent (D) described below. The thermosetting resin (C) contains, 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 resin (C) is preferably an epoxy resin.
The epoxy resin may be a compound having only one epoxy group in one molecule, or a compound having two or more epoxy groups in one molecule.

Examples of epoxy resins include bifunctional or crystalline epoxy resins such as biphenyl type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, stilbene type epoxy resins, and hydroquinone type epoxy resins; cresol novolac type epoxy resins; Novolak type epoxy resins such as phenol novolac type epoxy resins and naphthol novolac type epoxy resins; Resin; trifunctional epoxy resin such as triphenolmethane type epoxy resin and alkyl-modified triphenolmethane 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 Heterocyclic ring-containing epoxy resins such as containing epoxy resins and the like can be mentioned.

The epoxy group-containing compound may also include monofunctional epoxy group-containing compounds such as 4-tert-butylphenyl glycidyl ether, m,p-cresyl glycidyl ether, phenyl glycidyl ether, and cresyl glycidyl ether.
The paste-like resin composition of the present embodiment may contain only one type of thermosetting component, or may contain two or more types.

In the present embodiment, the thermosetting resin (C) and the (meth)acryloyl group-containing compound (A) are preferably used together. The ratio (mass ratio) when these are used in combination is not particularly limited, but for example, thermosetting resin (C) / (meth)acryloyl group-containing compound (A) = 95/5 to 50/50, preferably thermosetting Resin (C)/((meth)acryloyl group-containing compound (A))=90/10 to 60/40.

An epoxy resin is preferred as the thermosetting resin (C). As the epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin and the like are preferably mentioned.
The amount of the thermosetting resin (C) in the paste resin composition of the present embodiment is, for example, 3 to 20% by mass, preferably 5 to 15% by mass, based on the total nonvolatile components.

[Curing agent (D)]
The paste resin composition of the present embodiment can further contain a curing agent (D).

Examples of the curing agent (D) include those having a reactive group that reacts with the thermosetting resin (C). The curing agent (D) contains, for example, reactive groups that react with functional groups such as epoxy groups, maleimide groups, and hydroxy groups contained in the thermosetting resin (C).

Curing agent (D) preferably contains a phenolic curing agent and/or an imidazole curing agent. These curing agents are particularly preferred when the thermosetting component contains epoxy groups.
The phenol-based curing agent may be a low-molecular-weight compound or a high-molecular-weight compound (ie, phenolic resin).

Examples of phenol-based curing agents that are low-molecular-weight compounds include bisphenol compounds (phenolic resins having a bisphenol F skeleton) such as bisphenol A and bisphenol F (dihydroxydiphenylmethane); compounds having a biphenylene skeleton such as 4,4'-biphenol. etc.

Specific examples of phenolic resins include novolac-type phenolic resins such as phenol novolak resin, cresol novolak resin, bisphenol novolak resin, and phenol-biphenyl novolak resin; polyvinylphenol; polyfunctional phenolic resins such as triphenylmethane-type phenol resin; modified phenolic resins such as modified phenolic resins and dicyclopentadiene-modified phenolic resins; phenolic aralkyl-type phenolic resins such as phenolaralkyl resins having a phenylene skeleton and/or biphenylene skeleton and naphtholaralkyl resins having a phenylene and/or biphenylene skeleton; be able to.
When using the curing agent (D), only one type may be used, or two or more types may be used in combination.

When the paste-like resin composition of the present embodiment contains the curing agent (D), the amount thereof is, for example, 10 to 150 parts by mass, preferably 20 parts by mass when the amount of the thermosetting resin (C) is 100 parts by mass. ~100 parts by mass.

(Curing accelerator)
The paste resin composition of the present embodiment may further contain a curing accelerator.
A curing accelerator typically accelerates the reaction between the thermosetting resin (C) and the curing agent (D).

Specific examples of curing accelerators include phosphorus atom-containing compounds such as organic phosphines, tetrasubstituted phosphonium compounds, phosphobetaine compounds, adducts of phosphine compounds and quinone compounds, adducts of phosphonium compounds and silane compounds; dicyandiamide, 1 ,8-diazabicyclo[5.4.0]undecene-7, amidines and tertiary amines such as benzyldimethylamine; and nitrogen atom-containing compounds such as quaternary ammonium salts of the above amidines or the above tertiary amines.
When using a hardening accelerator, only 1 type may be used and 2 or more types may be used together.

When the paste resin composition of the present embodiment contains a curing accelerator, its amount is, for example, 0.1 to 10 parts by mass, preferably 0, when the amount of the thermosetting resin (C) is 100 parts by mass. .5 to 5 parts by mass.

(Silane coupling agent)
The paste resin composition of the present embodiment can further contain a silane coupling agent. This makes it possible to further improve the adhesive force.

Silane coupling agents include known silane coupling agents, specifically vinylsilanes such as nyltrimethoxysilane and vinyltriethoxysilane;
2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyl epoxy silanes such as methyldiethoxysilane, 3-glycidoxypropyltriethoxysilane;
styrylsilanes such as p-styryltrimethoxysilane;
methacryloxysilanes 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-ureidopropyltrialkoxysilane;
Mercaptosilanes such as 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane;
Examples include isocyanatosilanes such as 3-isocyanatopropyltriethoxysilane.
When using a silane coupling agent, only 1 type may be used and 2 or more types may be used together.

When the paste resin composition of the present embodiment contains a silane coupling agent, the amount thereof is the amount of the thermosetting component (the total amount of the (meth)acryloyl group-containing compound (A) and the thermosetting resin (C) ) is 100 parts by mass, it is, for example, 0.1 to 10 parts by mass, preferably 0.5 to 5 parts by mass.

(Plasticizer)
The paste resin composition of the present embodiment can contain a plasticizer. The plasticizer makes it easy to design the storage elastic modulus to be small. And it becomes easy to suppress the fall of the adhesive force by a heat cycle further.

Specific examples of plasticizers include silicone compounds such as polyester compounds, silicone oils and silicone rubbers, polybutadiene compounds such as polybutadiene maleic anhydride adducts, and acrylonitrile-butadiene copolymer compounds.
When using a plasticizer, only 1 type may be used and 2 or more types may be used together.

When the paste-like resin composition of the present embodiment contains a plasticizer, the amount thereof is the amount of the thermosetting component (the total amount of the (meth)acryloyl group-containing compound (A) and the thermosetting resin (C)). When 100 parts by mass, it is, for example, 5 to 50 parts by mass, preferably 10 to 30 parts by mass.

(radical initiator)
The paste resin composition of the present embodiment can contain a radical initiator.
The radical initiator can, for example, prevent insufficient curing, allow the curing reaction to proceed sufficiently at relatively low temperatures (e.g., 180°C), and further improve adhesive strength. may occur.
Examples of radical initiators include peroxides and azo compounds.

Examples of peroxides include organic peroxides such as diacyl peroxide, dialkyl peroxide, and peroxyketals, more specifically, ketone peroxides such as methyl ethyl ketone peroxide and cyclohexanone peroxide; Peroxyketals such as 1,1-di(t-butylperoxy)cyclohexane and 2,2-di(4,4-di(t-butylperoxy)cyclohexyl)propane;
Hydroperoxides such as p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide;
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)hexyne-3, di-t-butyl peroxide;
Diacyl peroxides such as dibenzoyl peroxide and di(4-methylbenzoyl) peroxide;
Peroxydicarbonates such as di-n-propyl peroxydicarbonate and diisopropyl peroxydicarbonate;
Peroxyesters such as 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, t-hexylperoxybenzoate, t-butylperoxybenzoate, t-butylperoxy 2-ethylhexanonate, etc. can be mentioned.

Azo compounds include 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis(2-cyclopropylpropionitrile), 2,2'-azobis(2, 4-dimethylvaleronitrile) and the like.
When using a radical initiator, only 1 type may be used and 2 or more types may be used together.

When the paste-like resin composition of the present embodiment contains a radical initiator, the amount thereof is the amount of the thermosetting component (the total amount of the (meth)acryloyl group-containing compound (A) and the thermosetting resin (C)). is 100 parts by mass, for example, 0.1 to 10 parts by mass, preferably 0.5 to 8 parts by mass, more preferably 0.5 to 5 parts by mass.

(solvent)
The paste resin composition of the present embodiment can further contain a solvent. By using the solvent, for example, it is possible to adjust the fluidity of the paste-like resin composition, improve the workability when forming the adhesive layer on the base material, and the like.

The solvent is typically an organic solvent.
Organic solvents include 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 monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, methylmethoxybutanol, α-terpineol, β-terpineol, hexylene glycol, benzyl alcohol, 2-phenylethyl alcohol, isopalmityl alcohol, iso Alcohols such as stearyl alcohol, lauryl alcohol, ethylene glycol, propylene glycol, butylpropylene triglycol, glycerin;
Acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, diacetone alcohol (4-hydroxy-4-methyl-2-pentanone), 2-octanone, isophorone (3,5,5-trimethyl-2-cyclohexen-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 octanoate, 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, and tripentyl phosphate;
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, light oil;
Nitriles such as acetonitrile or propionitrile;
amides such as acetamide and N,N-dimethylformamide;
Silicone oils such as low-molecular-weight volatile silicone oils and volatile organic modified silicone oils can be used.
When using a solvent, only one solvent may be used, or two or more solvents may be used in combination.

When using a solvent, the amount 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 such an amount that the non-volatile component concentration of the paste-like resin composition is 50 to 90% by mass.

(Properties of composition)
The paste resin composition of the present embodiment is preferably pasty at 20°C. That is, the paste resin composition of the present embodiment can preferably be applied to a substrate or the like at 20° C. like a paste. As a result, the paste resin composition of the present embodiment can be preferably used as an adhesive for semiconductor elements or the like.
Of course, depending on the applied process, etc., the paste resin composition of the present embodiment may be in the form of a varnish with a relatively low viscosity.

<High thermal conductivity material>
A high thermal conductivity material can be obtained by sintering the paste resin composition of the present embodiment.
By changing the shape of the high thermal conductivity material, it can be applied to various parts that require heat dissipation in the fields of automobiles and electrical machinery.

<Semiconductor device>
A semiconductor device can be manufactured using the paste resin composition of the present embodiment. For example, a semiconductor device can be manufactured by using the paste resin composition of the present embodiment as an "adhesive" between a substrate and a semiconductor element.

In other words, the semiconductor device of the present embodiment includes, for example, a substrate and a semiconductor element mounted on the substrate via an adhesive layer obtained by sintering the paste resin composition by heat treatment. Prepare.
In the semiconductor device of the present embodiment, the adhesiveness of the adhesive layer is less likely to deteriorate due to heat cycles. That is, the reliability of the semiconductor device of this embodiment is high.
Examples of semiconductor devices include ICs, LSIs, power semiconductor devices (power semiconductors), and various other devices.
Examples of substrates include various semiconductor wafers, lead frames, BGA substrates, mounting substrates, heat spreaders, and heat sinks.

An example of a semiconductor device will be described below 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 (die attach material) that is a heat-treated paste resin composition.

The semiconductor element 20 and the base material 30 are electrically connected via bonding wires 40 or the like, for example. Also, the semiconductor element 20 is sealed with a sealing resin 50, for example.

The thickness of the adhesive layer 10 is preferably 5 μm or more, more preferably 10 μm or more, and even more preferably 20 μm or more. Thereby, the stress absorption capacity of the paste-like resin 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 with the adhesive layer 10 interposed therebetween. Also, the semiconductor element 20 is electrically connected to the outer leads 34 (the base material 30) via bonding wires 40, for example. The base material 30, which is a lead frame, is composed of, for example, 42 alloy, a Cu frame, or the like.

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

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

An example of a method for manufacturing a semiconductor device will be described.
First, the base material 30 is coated with a paste resin composition, and then the semiconductor element 20 is arranged thereon. That is, the base material 30, the paste resin composition, and the semiconductor element 20 are laminated in this order.
The method of applying the paste resin composition is not particularly limited. Specifically, a dispensing method, a printing method, an inkjet method, and the like can be mentioned.

Next, the paste resin composition is heat-cured. Thermal curing is preferably carried out by pre-curing and post-curing. By thermosetting, the paste-like resin composition is made into a heat-treated product (cured product). By thermosetting (heat treatment), the metal-containing particles in the paste-like resin composition are aggregated, and a structure is formed in the adhesive layer 10 in which interfaces between a plurality of metal-containing particles have disappeared. Thereby, the substrate 30 and the semiconductor element 20 are adhered via the adhesive layer 10 . Next, the semiconductor element 20 and the base material 30 are electrically connected using bonding wires 40 . Then, the semiconductor element 20 is sealed with the sealing resin 50 . Thus, a 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 those described above can be adopted. Moreover, the present invention is not limited to the above-described embodiments, and includes modifications, improvements, etc. within the scope of achieving the object of the present invention.

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

<Preparation of paste resin composition>
First, each raw material component was mixed according to the compounding amounts 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 in a three-roll mill. Thus, a paste resin composition was produced.

Information on raw material components in Table 1 is shown below.
(Thermosetting component)
・ Epoxy resin 1: Bisphenol F type liquid epoxy resin (manufactured by Nippon Kayaku, RE-303S)

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

((Meth)acryloyl group-containing compound)
・ Acrylic monomer 1: ethylene glycol dimethacrylate (manufactured by Kyoei Chemical Co., Ltd., Light Ester EG)
-Acrylic monomer 2: Polyethylene glycol #600 dimethacrylate (n in general formula (1) is 14) (manufactured by NOF Corporation, PDE600)
-Acrylic monomer 3: Polyethylene glycol #600 dimethacrylate (n in general formula (1) is 14) (Kyoeisha Chemical Co., Ltd., Light Ester 14EG)
-Acrylic monomer 4: polyethylene glycol #1000 diacrylate (n in general formula (1) is 23) (Shin-Nakamura Chemical Co., Ltd., A-1000)

(Plasticizer)
- Plasticizer 1: allyl resin (manufactured by Kanto Chemical Co., Ltd., polymer of bis(2-propenyl) 1,2-cyclohexanedicarboxylate and propane-1,2-diol)

(Curing accelerator)
- Imidazole curing agent 1: 2-phenyl-1H-imidazole-4,5-dimethanol (manufactured by Shikoku Kasei Kogyo Co., Ltd., 2PHZ-PW)

(Polymerization initiator)
- Radical polymerization initiator 1: Dicumyl peroxide (manufactured by Kayaku Akzo Co., Ltd., Perkadox BC)

(Metal-containing particles)
・ Silver particles 1: silver powder (manufactured by Fukuda Metal Foil & Powder Co., Ltd., HKD-38, flaky, D ₅₀ : 4 μm)
・Silver-coated resin particles 1: Silver-plated silicone resin particles (manufactured by Mitsubishi Materials Corporation, heat-resistant and surface-treated 10 μm product, spherical shape, D ₅₀ : 10 μm, specific gravity: 2.3, silver weight ratio 50 wt%, resin weight ratio 50 wt%)

(solvent)
・ Solvent 1: butyl propylene triglycol (BFTG)

<Measurement of thermal conductivity λ>
The resulting paste resin composition was applied to a Teflon plate, heated from 30° C. to 200° C. over 60 minutes in a nitrogen atmosphere, and then heat-treated at 200° C. for 120 minutes. As a result, a 1 mm-thick heat-treated body of the paste-like resin composition was obtained ("Teflon" is a registered trademark for fluororesin).
Then, the thermal diffusion coefficient α in the thickness direction of the heat-treated body was measured by the laser flash method. The measurement temperature was 25°C.
Also, the specific heat Cp was measured by differential scanning calorimetry (DSC).
Furthermore, the density ρ was measured according to JIS K 6911.
Using these values, the thermal conductivity λ was calculated according to the following formula.
Thermal conductivity λ [W/(m K)] = α [m ² /sec] x Cp [J/kg K] x ρ [g/cm ³ ]

<Measurement of electrical resistivity>
The resulting paste-like resin composition was applied onto a glass plate, heated from 30° C. to 200° C. over 60 minutes in a nitrogen atmosphere, and then heat-treated at 200° C. for 120 minutes. As a result, a heat-treated paste resin composition having a thickness of 0.05 mm was obtained. The resistance value of the surface of the heat-treated body was measured using a direct current four-electrode method with a milliohmmeter (manufactured by Hioki Co., Ltd.) and electrodes with an electrode spacing of 40 mm.

<Measurement of storage modulus E' at 25°C>
The resulting paste resin composition was applied to a Teflon plate, heated from 30° C. to 200° C. over 60 minutes, and then heat-treated at 200° C. for 120 minutes. As a result, a heat-treated body of the thermally conductive composition having a thickness of 0.3 mm was obtained.
The obtained heat-treated body was peeled off from the Teflon plate, set in a measuring device (DMS6100, manufactured by Hitachi High-Tech Science Co., Ltd.), and subjected to dynamic viscoelasticity measurement (DMA) in a tensile mode at a frequency of 1 Hz. Thereby, the storage elastic modulus E' (MPa) at 25°C was measured.

<Measurement of breaking strength>
The resulting paste resin composition was applied to a Teflon plate, heated from 30° C. to 200° C. over 60 minutes, and then heat-treated at 200° C. for 120 minutes. As a result, a heat-treated body of the thermally conductive composition having a thickness of 0.3 mm and a width of 4 mm was obtained. Then, the breaking strength of each test sample at 25° C. was measured using a tensile tester (manufactured by Shimadzu Corporation, “MST-1”).

<Measurement of breaking strain>
The breaking strain was calculated by dividing the elongation from the origin of elongation (initial distance between chucks) to the breaking point of each test piece (displacement amount when the test piece breaks) by the initial distance between chucks.

<Measurement of breaking energy>
The breaking point energy was calculated by integrating the stress from the origin of elongation (initial distance between chucks) to the breaking point of each test piece (displacement amount when the test piece broke) by displacement. The obtained energy at break was divided by the volume of the specimen to obtain the energy at break per unit volume (mJ/mm ³ ).

<Heat cycle test/evaluation of the presence or absence of peeling>
The paste-like resin composition was applied onto a surface-silver-plated substrate to form a coating film, and a 7×7 mm surface-gold-plated silicon chip was placed on the coating film. Thereafter, the temperature was raised from 30° C. to 200° C. over 60 minutes, followed by heat treatment at 200° C. for 120 minutes. As described above, the thermally conductive composition was cured, and the silicon chip was bonded to the substrate.
The bonded silicon chip/substrate was sealed with a sealing material EME-G700ML-C (manufactured by Sumitomo Bakelite). This was used as a sample for the temperature cycle test.
The samples were placed in a 60°C/60% RH high-temperature, high-humidity bath and treated for 48 hours, followed by a 260°C reflow treatment.
The sample after reflow treatment was put into a temperature cycle tester TSA-72ES (manufactured by Espec), (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 with no peeling were evaluated as ◯ (good), and those with peeling were evaluated as x (bad).

From the results of Table 1, by bonding the semiconductor element and the base material using the paste resin composition of the present invention, good conductivity is exhibited over a long period of time, and a semiconductor device with excellent long-term reliability. It was found that it is possible to obtain

This application claims priority based on Japanese Patent Application No. 2020-012506 filed on January 29, 2020, and the entire disclosure thereof is incorporated herein.

Claims (5)

A paste resin composition for obtaining a high thermal conductivity material by sintering, wherein the high thermal conductivity material after sintering is 26 W / mK or more under the measurement conditions described below. Paste for high thermal conductivity material A shaped resin composition,
(A) a (meth)acryloyl group-containing compound containing at least one selected from compounds represented by the following general formula (1);
(B) metal-containing particles, including silver-containing particles or copper-containing particles;
(C) a thermosetting resin (C) (excluding (meth)acryloyl group-containing compound (A));
A paste-like resin composition for highly thermally conductive materials containing (excluding the case where a β-dicarbonyl compound is contained).

(In the general formula (1), R represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and multiple R may be the same or different. X is a hydrogen atom, a halogen atom, an amino group, a cyano group , a mercapto group, a carboxyl group, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and multiple X may be the same or different, m is an integer of 2 to 10 .n represents an integer of 8 or more and 30 or less.)
[Measurement condition]
The paste resin composition is applied on a Teflon plate, heated from 30° C. to 200° C. over 60 minutes in a nitrogen atmosphere, and then heat-treated at 200° C. for 120 minutes to be sintered. This yields a highly thermally conductive material with a thickness of 1 mm. Next, the thermal diffusion coefficient α in the thickness direction of the high thermal conductivity material is measured by the laser flash method (measurement temperature 25° C.). Also, the specific heat Cp is measured by differential scanning calorimetry. Furthermore, the density ρ is measured according to JIS K 6911. Using these values, the thermal conductivity λ is calculated based on the following formula.
Thermal conductivity λ [W/(m K)] = α [m ² /sec] x Cp [J/kg K] x ρ [g/cm ³ ] The paste resin composition for high thermal conductivity material according to claim 1, wherein the thermosetting resin (C) contains an epoxy resin. 3. The paste resin composition for high thermal conductivity material according to claim 1, further comprising a curing agent (D). A highly thermally conductive material obtained by sintering the paste resin composition for a highly thermally conductive material according to any one of claims 1 to 3. a substrate;
A semiconductor element mounted on the base material via an adhesive layer,
A semiconductor device, wherein the adhesive layer is formed by sintering the paste resin composition for a high thermal conductivity material according to any one of claims 1 to 3.

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