JPH11284114A - Semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a chip size package type semiconductor device using a heat spreader which has a stress relaxing ability, heat resistance, electrolytic corrosion resistance and moisture resistance and is previously coated with and adhesive which reduces the deterioration caused by the moisture-resistance test under severe conditions such as pressure cooker test treatment. SOLUTION: Using a heat spreader 5 previously coated with an adhesive 3 a semiconductor chip 2 is adhered to the heat spreader 5, the adhesive 3 contains an epoxy resin having a wt. average mol.wt. of less than 5000 and its hardening agent 100 parts wt. in total, together with a hardening accelerator 0.1-5 parts wt. and epoxy group-contg. acrylic copolymer contg. a copolymer unit origination from glycidile (meta)acrylate 2-6 wt.% and having a glass transition temp. of -10 deg.C or higher and wt. average mol.wt. of 600000 or more, 100-300 parts wt.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a chip-size package type semiconductor device having a heat spreader.

[0002]

2. Description of the Related Art In recent years, the mounting density of electronic components has increased with the development of electronic devices, and semiconductor devices have been reduced in size.
2. Description of the Related Art A chip size package (CSP, sometimes referred to as a CSP hereinafter) having substantially the same size as a semiconductor chip is used. A CSP is a product formed by mounting a semiconductor chip on a substrate that connects an external terminal with a semiconductor chip called an interposer. Unlike a semiconductor bare chip,
It is a reliable electronic component that has passed quality inspection. With the recent increase in the degree of integration of semiconductor devices, the amount of heat generated during operation has been increasing, and in order to suppress heat generation of the semiconductor device, along with essential improvements such as a reduction in operating voltage and a design with less loss, Countermeasures such as forced cooling with a fan and installation of a heat spreader and a radiation fin for radiation are taken.

In order to directly attach a heat spreader such as aluminum or copper having excellent heat dissipation to a semiconductor chip, a large difference in the coefficient of thermal expansion between the heat spreader and the semiconductor chip is required. It is necessary to use an adhesive that can alleviate the generated stress, and that has heat resistance, electrolytic corrosion resistance, and moisture resistance, and that is less likely to deteriorate when subjected to a moisture resistance test under severe conditions such as PCT treatment. However, conventionally known adhesives could not satisfy these requirements.

For example, as an interposer used for a CSP, a thermal expansion coefficient of a semiconductor chip is about 4 ppm / ° C.
Ceramic substrates made of alumina or the like having a thermal expansion coefficient close to that of polyimide, flexible polyimide tape, or thick polyimide substrate are used (Nikkei Electronics 199).
6 years No. No. 668), an adhesive is used to fix the semiconductor chip to the interposer. When a ceramic substrate is used for the interposer, a liquid adhesive represented by a silver paste is used. However, liquid adhesives have problems such as the need to pay attention to the storage stability of the adhesive, and the workability is inferior to LOC and the like. Therefore, there is a problem that the dispersion is not uniform.

As the adhesive for semiconductors, in addition to a paste such as a silver paste or a liquid adhesive, a film adhesive is used for a flexible printed wiring board or the like, and there are many systems mainly composed of acrylonitrile butadiene rubber. .

JP-A-60-243180 discloses a film adhesive containing an acrylic resin, an epoxy resin, a polyisocyanate and an inorganic filler, and JP-A-61-138680 discloses an acrylic resin. , An epoxy resin, a film-like adhesive containing a primary amine compound having a urethane bond in the molecule at both ends and an inorganic filler. Although such film adhesives are often used mainly of acrylonitrile butadiene rubber, the adhesive strength after a long-time treatment at high temperature has a large decrease, and the electrolytic corrosion resistance is poor. There were drawbacks. In particular, when a moisture resistance test was performed under severe conditions such as a PCT (pressure cooker test) process used in reliability evaluation of semiconductor-related components, deterioration was large. For example, Japanese Patent Application Laid-Open No. Sho 60-243180
JP-A-61-138680, when subjected to a moisture resistance test under severe conditions such as PCT treatment, the deterioration was large and insufficient.

When a heat spreader made of aluminum or copper is bonded to a semiconductor chip using an adhesive as a material related to the printed wiring board, the difference in the thermal expansion coefficient between the heat spreader and the semiconductor chip is large, and the heat spreader and the semiconductor chip have a large difference in thermal expansion. It is not suitable for practical use because cracks are generated at the time of heat generation, and when a moisture resistance test is performed under severe conditions such as a temperature cycle test or a PCT process, deterioration is large.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a CSP type semiconductor device having a heat spreader for radiating heat, which is used for bonding a semiconductor chip having a large difference in thermal expansion coefficient from the heat spreader. A semiconductor device using a heat spreader pre-coated with an adhesive that has an ability, heat resistance, electrolytic corrosion resistance, and moisture resistance, and that reduces deterioration when subjected to a moisture resistance test particularly under severe conditions such as PCT processing. The purpose is to provide.

[0009]

SUMMARY OF THE INVENTION The present invention is directed to a chip-size package (chip-scale package) type semiconductor device having a heat spreader for improving heat dissipation, comprising a heat spreader to which an adhesive has been applied in advance. The semiconductor chip and the heat spreader are bonded together using an adhesive, and the adhesive is (1) a total amount of 100 parts by weight of an epoxy resin (1a) having a weight average molecular weight of less than 5,000 and a curing agent (1b) thereof, 2) Hardening accelerator
1-5 parts by weight and (3) 2-6% by weight of copolymerized units derived from glycidyl (meth) acrylate having a glass transition temperature of -10 ° C or higher and a weight average molecular weight of 60
An object of the present invention is to provide a semiconductor device containing 100 to 300 parts by weight of an epoxy group-containing acrylic copolymer having a molecular weight of 000 or more.

The present invention also provides, as one aspect of the semiconductor device of the present invention, a semiconductor device in which the curing agent (1b) in the adhesive is a phenol resin.

According to the present invention, as one aspect of the semiconductor device of the present invention, the adhesive may further comprise an epoxy resin (1a).
And the curing agent (1b) in a total amount of 100 parts by weight,
(4) High-molecular-weight resins having compatibility with the epoxy resin (1a) and having a weight average molecular weight of 30,000 or more.
It is intended to provide a semiconductor device containing 0 parts by weight.

According to another aspect of the present invention, there is provided a semiconductor device according to the present invention, wherein the high molecular weight resin having a weight-average molecular weight of 30,000 or more is a phenoxy resin, which is compatible with the epoxy resin (1a). An apparatus is provided.

According to another aspect of the present invention, there is provided a semiconductor device according to the present invention, wherein a heat spreader to which an adhesive is applied in advance is applied to a heat spreader by applying a varnish in which the adhesive is dissolved in a solvent, and then heating the solvent. To provide a semiconductor device which is a heat spreader with an adhesive obtained by forming an adhesive layer on the heat spreader by removing the heat spreader.

According to another aspect of the present invention, as an embodiment of the semiconductor device, the adhesive forming the adhesive layer on the heat spreader with the adhesive is completely cured when the adhesive is measured using a DSC. An object of the present invention is to provide a semiconductor device in a state where heat generation of 10 to 40% of a calorific value has been completed.

According to the present invention, as one mode of the semiconductor device of the present invention, the above-mentioned adhesive is cured to a state in which heat generation of 100% of the total curing calorific value measured by using a DSC is completed. The storage elastic modulus when measured using a dynamic viscoelasticity measurement device is 20 to 2,000 MPa at 25 ° C.,
An object of the present invention is to provide a semiconductor device having a temperature of 3 to 50 MPa at 260 ° C.

According to the present invention, as one mode of the semiconductor device of the present invention, the above-mentioned adhesive may contain 2 to 20 inorganic fillers.
An object of the present invention is to provide a semiconductor device which contains a volume%.

According to another aspect of the present invention, there is provided a semiconductor device in which the inorganic filler is selected from the group consisting of alumina, silica, silicon carbide, boron nitride, and aluminum nitride. .

According to the present invention, as one mode of the semiconductor device of the present invention, the heat spreader is made of aluminum, copper,
An object of the present invention is to provide a semiconductor device formed of a metal selected from the group consisting of an aluminum alloy and a copper alloy.

The present invention also provides, as one mode of the semiconductor device of the present invention, a semiconductor device in which at least a portion of a heat spreader to which an adhesive is applied is subjected to a surface treatment with a coupling agent. .

According to the present invention, as one aspect of the semiconductor device of the present invention, the heat spreader is formed of copper or a copper alloy, and at least a portion of the heat spreader to which the adhesive is applied is subjected to blackening treatment. A semiconductor device is provided.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the adhesive used in the present invention will be described.

The epoxy resin (1a) in the adhesive used in the present invention may be any as long as it cures and exhibits an adhesive action. Bifunctional or more, molecular weight or weight average molecular weight (polystyrene conversion value, the same applies hereinafter) is less than 5,000,
For example, 300 to less than 5,000, preferably 3,000
Less than 300, for example less than 3,000 epoxy resins are used. In particular, it is preferable to use a bisphenol A type or bisphenol F type liquid resin having a weight average molecular weight of 500 or less, since the fluidity at the time of bonding the heat spreader to the semiconductor chip can be improved. Bisphenol A-type or bisphenol F-type liquid resins having a weight average molecular weight of 500 or less are obtained from Yuka Shell Epoxy Co., Ltd., and are Epicoat 807, Epicoat 827, Epicoat 828.
It is marketed under the trade name. In addition, Dow Chemical Japan Co., Ltd. E. FIG. R. 330, D.I. E. FIG. R.
331; E. FIG. R. 361. In addition, YD128, Y
It is marketed under the trade name DF170.

As the epoxy resin (1a), a trifunctional or higher polyfunctional epoxy resin may be used for the purpose of increasing Tg. Examples of the polyfunctional epoxy resin include a phenol novolak type epoxy resin and a cresol novolak type epoxy resin. Is exemplified. When using a trifunctional or higher polyfunctional epoxy resin, the amount is preferably 10 to 50% by weight of the total amount of the bifunctional epoxy resin and the polyfunctional epoxy resin.

Examples of the phenol novolak type epoxy resin include those commercially available from Nippon Kayaku Co., Ltd. under the trade name EPPN-201. Also,
Examples of the cresol novolak type epoxy resin include ESCN-001, ESCN from Sumitomo Chemical Co., Ltd.
-195 and EOCN1012, EOCN1025, EOCN
A product marketed under the trade name of 1027 is exemplified.

As the curing agent (1b) for the epoxy resin (1a), those usually used as curing agents for the epoxy resin can be used, and amine, polyamide, acid anhydride, polysulfide, boron trifluoride and phenolic 1 hydroxyl group
Examples thereof include bisphenol A, bisphenol F, bisphenol S, and phenol resins, which are compounds having two or more in the molecule. In particular, it is preferable to use a phenol resin such as a phenol novolak resin, a bisphenol novolak resin, and a cresol novolak resin because of excellent electric corrosion resistance during moisture absorption. For example, these resins have a weight average molecular weight of 500 to 2,000,
Those having a size of from 00 to 1,500 are preferably used.

Examples of such particularly preferred curing agents include phenolite LF2882 and phenolite LF2 available from Dainippon Ink and Chemicals, Inc.
822, phenolite TD-2090, phenolite T
D-2149, phenolite VH4150, phenolite VH4170 (trade name) and the like.

The curing agent (1b) is preferably used in such an amount that a group having reactivity with an epoxy group, for example, a phenolic hydroxyl group is 0.8 to 1.2 mol per mol of epoxy group in the adhesive. , And more preferably in an amount of 0.95 to 1.05 mol.

A curing accelerator is used together with the curing agent (1b). It is preferable to use various imidazoles as the curing accelerator (4). Examples of imidazole include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole,
-Cyanoethyl-2-phenylimidazolium trimellitate;

Examples of commercially available imidazoles include 2E4MZ, 2PZ-CN,
Examples include those commercially available under the trade name of PZ-CNS.

The amount of the curing accelerator is determined by the amount of the epoxy resin (1a)
And 0.1 part of the total amount of the curing agent (1b) and 100 parts by weight.
1 to 5 parts by weight.

The epoxy group-containing acrylic copolymer used in the present invention contains 2 to 6% by weight of copolymerized units derived from glycidyl (meth) acrylate and has a Tg (glass transition temperature) of -10 ° C. or higher, for example, -10 ° C to 30 ° C and a weight average molecular weight of 600,000 or more, for example, 60
000 to 2,000,000, preferably 800,
000 to 1,200,000. Such an epoxy group-containing acrylic copolymer is commercially available from Teikoku Chemical Industry Co., Ltd. under the trade name HTR-860.
P-3 can be used. Here, (meth) acrylate means acrylate and / or methacrylate. For example, glycidyl (meth) acrylate means glycidyl acrylate and / or glycidyl methacrylate. When the amount of the copolymer unit derived from glycidyl (meth) acrylate in the epoxy group-containing acrylic copolymer is less than 2% by weight, the adhesive strength of the adhesive tends to be insufficient, and 6% by weight If it exceeds, gelling of the epoxy group-containing acrylic copolymer may easily occur. When the Tg of the epoxy group-containing acrylic copolymer is lower than -10 ° C, the tackiness of the adhesive in the B-stage state increases, and the handling property of the heat spreader with the adhesive may be deteriorated. The epoxy group-containing acrylic copolymer has a weight average molecular weight of 600,00.
If it is less than 0, the strength and handleability of the heat spreader with adhesive may deteriorate due to a decrease in the strength and flexibility of the adhesive layer and an increase in tackiness.

As the copolymerizable monomer other than glycidyl (meth) acrylate used in the synthesis of the epoxy group-containing acrylic copolymer, for example, acrylonitrile, alkyl (meth) acrylate and the like are preferable. Examples of the alkyl (meth) acrylate include ethyl (meth) acrylate, butyl (meth) acrylate, and the like. When a monomer having a functional group such as a carboxyl group or a hydroxyl group, for example, a carboxylic acid type acrylic acid or a hydroxyl group type hydroxymethyl (meth) acrylate is used, the crosslinking reaction proceeds easily, and the adhesive is gelled in a varnish state. However, it is not preferable because there is a problem such as a decrease in adhesive strength due to an increase in the degree of curing in the B stage state.

The Tg (glass transition temperature) containing 2 to 6% by weight of copolymerized units derived from glycidyl (meth) acrylate is -10 ° C. or more and the weight average molecular weight is 600,0
Specific examples of the epoxy group-containing acrylic copolymer having a molecular weight of 00 or more include (a) acrylonitrile 18 to
40% by weight, (b) 2 to 6% by weight of glycidyl (meth) acrylate as a functional group monomer, and (c) at least one monomer 54 to 80 selected from the group consisting of ethyl acrylate, ethyl methacrylate, butyl acrylate and butyl methacrylate. Copolymers obtained by copolymerizing by weight% are exemplified. Ethyl acrylate, ethyl methacrylate, butyl acrylate and butyl methacrylate can be used alone or in combination of two or more, and the mixing ratio is determined in consideration of the Tg of the copolymer. Examples of the polymerization method include pearl polymerization, solution polymerization, and the like, which can be obtained.

The compounding amount of the epoxy group-containing acrylic copolymer in the adhesive used in the present invention is as follows.
It is 100 to 300 parts by weight based on 100 parts by weight of the total amount of a) and the curing agent (1b). If the amount of the epoxy group-containing acrylic copolymer is less than 100 parts by weight, the strength of the adhesive layer may be reduced or the tackiness may be increased.
If the amount exceeds 0 parts by weight, the phase of the epoxy group-containing acrylic copolymer which is a rubber component in the adhesive increases, and the epoxy resin phase decreases, so that the handleability at high temperatures may deteriorate.

The high molecular weight resin compatible with the epoxy resin (1a) and having a weight average molecular weight of 30,000 or more includes phenoxy resin, high molecular weight epoxy resin, ultrahigh molecular weight epoxy resin, and rubber having a high polarity functional group. And a highly polar functional group-containing reactive rubber. By blending a high molecular weight resin having a weight average molecular weight of 30,000 or more, the tackiness of the adhesive in the B stage can be reduced and the flexibility at the time of curing can be improved. Therefore, the weight average molecular weight of the high molecular weight resin (2) is set to 30,000 or more, preferably 30,000.
0 to 600,000, more preferably 30,000 to 3
00,000, more preferably 45,000 to 200,
000. Here, “compatible with the epoxy resin (1a)” means a property of forming a homogeneous mixture without being separated from the epoxy resin (1a) after curing and being separated into two or more phases.

Examples of commercially available phenoxy resins include those commercially available from Toto Kasei Co., Ltd. under the trade names such as Phenotote YP-40, Phenotote YP-50, and Phenotote YP-60.

As the high molecular weight epoxy resin, a high molecular weight epoxy resin having a weight average molecular weight of 30,000 to 80,000 is used, and as the ultrahigh molecular weight epoxy resin, one having a weight average molecular weight exceeding 80,000, preferably 80 ,
000 and 200,000 or less (Japanese Patent Publication No. 7-59617, Japanese Patent Publication No. 7-59618).
JP, JP-B7-59619, JP-B7-59
No. 620, Japanese Patent Publication No. 7-64911, Japanese Patent Publication No. 7-64911
All are manufactured by Hitachi Chemical Co., Ltd. and are commercially available.

Examples of the reactive rubber having a high polarity functional group include acrylonitrile butadiene rubber and acrylic rubber to which a highly polar functional group such as a carboxyl group is added. Commercially available carboxyl group-containing acrylonitrile butadiene rubber includes PNR-1 (trade name) commercially available from Nippon Synthetic Rubber Co., Ltd. and Nipol 1072M commercially available from Zeon Corporation.
(Product name). Commercially available carboxyl group-containing acrylic rubbers include HTR-860P (trade name) commercially available from Teikoku Chemical Industry Co., Ltd.

The adhesive used in the present invention is compatible with the epoxy resin and has a weight average molecular weight of 30,0.
The amount of the high molecular weight resin of 00 or more is the epoxy resin (1
The amount is 10 to 40 parts by weight based on 100 parts by weight of the total of a) and the curing agent (1b). When the amount of the high molecular weight resin is less than 10 parts by weight, insufficient flexibility of a phase containing epoxy resin as a main component (hereinafter, referred to as epoxy resin phase), reduction of tackiness, and deterioration of insulation due to cracks or the like are prevented. The effect tends to be insufficient, and if it exceeds 40 parts by weight, the Tg of the epoxy resin phase may decrease.

A coupling agent may be added to the adhesive in order to improve interfacial bonding between different materials.
As the coupling agent, a silane coupling agent is preferable.

Examples of the silane coupling agent include γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, N-β-aminoethyl -Γ-aminopropyltrimethoxysilane and the like.

The above-mentioned silane coupling agent is such that γ-glycidoxypropyltrimethoxysilane is NUC A-
187, γ-mercaptopropyltrimethoxysilane is NUC A-189, γ-aminopropyltriethoxysilane is NUC A-1100, γ-ureidopropyltriethoxysilane is NUC A-1160, N-β-
Aminoethyl-γ-aminopropyltrimethoxysilane is commercially available from Nippon Unicar Co., Ltd. under the trade name NUC A-1120, and can be suitably used.

The amount of the coupling agent is preferably 0.1 to 9% by weight in the adhesive, from the viewpoint of the effect and cost of the addition.

Further, in order to adsorb ionic impurities and improve insulation reliability during moisture absorption, an ion scavenger can be blended. The amount of the ion scavenger is 5 to 10% by weight in the adhesive, depending on the effect of the addition, heat resistance, and cost.
Is preferred. As the ion scavenger, a compound known as a copper harm inhibitor, for example, a triazine thiol compound or a bisphenol-based reducing agent, for preventing ionization and dissolution of copper can also be blended. Examples of bisphenol-based reducing agents include 2,2'-methylene-bis- (4-methyl-6-tert-butylphenol) and 4,4'-thio-bis- (3-methyl-6-tert-butylphenol).
And the like.

A copper damage inhibitor containing a triazinethiol compound as a component is commercially available from Sankyo Pharmaceutical Co., Ltd. under the trade name Disnet DB. Further, a copper damage inhibitor containing a bisphenol-based reducing agent as a component is commercially available from Yoshitomi Pharmaceutical Co., Ltd. under the trade name Yoshinox BB.

Further, for the purpose of improving the handleability and thermal conductivity of the adhesive, imparting flame retardancy, adjusting the melt viscosity, imparting thixotropic properties, improving the surface hardness, and the like, You may mix | blend an inorganic filler with an adhesive agent. The amount of the inorganic filler in the adhesive is preferably 2 to 20% by volume. If the amount of the inorganic filler is less than 2% by volume, the effect of blending may be insufficient,
If it exceeds 0% by volume, problems such as an increase in the storage elastic modulus of the adhesive, a decrease in the adhesiveness, and a decrease in the electrical properties due to voids may be caused.

Examples of the inorganic filler include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, alumina powder, aluminum nitride powder, aluminum borate whisker, and boron nitride powder. And silica such as crystalline silica and amorphous silica.

To improve thermal conductivity, alumina,
Aluminum nitride, boron nitride, crystalline silica, amorphous silica and the like are particularly preferred.

Of these, alumina is preferred because it has good heat dissipation, good heat resistance and good insulation. In addition, crystalline silica or amorphous silica is inferior to alumina in terms of heat radiation, but has less ionic impurities, so it has high insulation properties during PCT processing, and corrodes copper foil, aluminum wire, aluminum plate, etc. It is suitable in that it has few points.

In order to provide flame retardancy, aluminum hydroxide, magnesium hydroxide and the like are preferable.

For the purpose of adjusting the melt viscosity and imparting thixotropic properties, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, alumina, Silica and amorphous silica are preferred.

For improving the surface hardness, short fiber alumina, aluminum borate whisker and the like are preferable.

In the semiconductor device of the present invention, the semiconductor chip and the heat spreader are bonded using a heat spreader to which the above-mentioned adhesive has been applied in advance. FIG. 1 is a cross-sectional view of one embodiment of a semiconductor device of the present invention. In the semiconductor device shown in FIG. 1, for example, a semiconductor chip (2) is bonded face-down with an adhesive (3) to a substrate (1) with wiring, and a chip-side terminal and a substrate-side terminal are connected to an inner lead (4). And joined by inner lead bonding. Further, a heat spreader (5) with an adhesive is adhered to the upper surface of the semiconductor chip (2), and the joint and the side surface of the chip are covered with a sealing material 6, thereby obtaining a completed product. In the semiconductor device of FIG. 1, external terminals (solder balls) (7) are further attached to the wiring board (1). In the present invention, the substrate is not particularly limited as long as it is used for mounting a semiconductor chip. For example, a ceramic substrate such as alumina, a flexible heat-resistant resin tape (such as a polyimide tape), a thick heat-resistant resin substrate (Such as a polyimide substrate).

As the heat spreader to which the adhesive has been applied in advance, a varnish in which the adhesive is dissolved in a solvent is applied to the heat spreader, and the solvent is removed by heating to form an adhesive layer on the heat spreader. It is preferable to use a heat spreader with an adhesive obtained by the above method.

In the heat spreader with an adhesive used in the present invention, the components of the adhesive are dissolved or dispersed to form a varnish, and the varnish is applied on the heat spreader, and the solvent is removed by heating to form an adhesive layer on the heat spreader. Obtained by forming.

As the heat spreader, aluminum, copper, an aluminum alloy, a copper alloy, or the like is used, but is not particularly limited as long as it has excellent heat conductivity. The shape and size of the heat spreader are not particularly limited as long as they are plate-shaped or foil-shaped, which is generally equal to or larger than the surface of the semiconductor chip to which the heat spreader is bonded. Further, the heat spreader preferably has a size that does not protrude from the outer periphery of the package. Further, the thickness of the heat spreader is 50 to 50 from the viewpoint of maintaining heat dissipation and strength.
200 μm, preferably 100 to 150 μm
Is more preferred.

In order to improve the adhesion to the adhesive layer,
It is preferable to modify the surface of the heat spreader that contacts the adhesive. In the case of aluminum, surface treatment such as surface roughening and a coupling agent is particularly preferable. Examples of the coupling agent used for the surface treatment include those exemplified above. In the case of copper or a copper alloy, it is preferable to perform a general blackening treatment as a surface treatment of the inner layer circuit of the wiring board. Further, an oxidation treatment or an oxidation-reduction treatment or the like, or a surface roughening treatment by sandblasting or the like is also preferable.

Solvents used for varnishing adhesives include methyl ethyl ketone, acetone, methyl isobutyl ketone, 2-ethoxyethanol, toluene, butyl cellosolve, methanol, ethanol, and the like having relatively low boiling points.
It is preferable to use -methoxyethanol or the like. Further, a high boiling point solvent may be added for the purpose of improving the coating properties. Examples of the high boiling point solvent include dimethylacetamide, N-methylpyrrolidone, dimethylformamide, cyclohexanone and the like.

When the dispersion of the inorganic filler is taken into consideration, the production of the varnish can be carried out by using a mill, a three-roll mill, a bead mill, or a combination thereof. After pre-mixing the filler and low molecular weight material,
By blending a high molecular weight substance, the time required for mixing can be shortened. After the varnish is formed, it is preferable to remove bubbles in the varnish by vacuum degassing.

The coating method is not particularly limited,
For example, a comma coat, a roll coat, a reverse roll coat, a gravure coat, a bar coat, a blade coat and the like can be mentioned.

An adhesive varnish is applied on the heat spreader and dried by heating to remove the solvent. The heating temperature is
The heating time is usually 90 to 200 ° C, preferably 120 to 150 ° C, and the heating time varies depending on the amount of the solvent in the varnish, the thickness of the coating film, and the like, but is usually 3 to 10 minutes, preferably 4 to 4 minutes.
7 minutes. The adhesive layer formed by this is DSC
10-40% of the total curing calorific value of the adhesive measured by using
It is preferable that the heat generation is completed (curing degree: 10 to 40%). Heat is applied when the solvent is removed. At this time, the curing reaction of the adhesive proceeds and gels. The cured state at that time affects the fluidity of the adhesive, and optimizes adhesiveness and handleability. The DSC (differential scanning calorimetry) is based on a zero-position method of supplying or removing a calorific value so as to constantly cancel a temperature difference between a standard sample having no heat generation and heat absorption within a measurement temperature range. The device is commercially available and can be measured using it. The curing reaction of the adhesive is an exothermic reaction. When the temperature of the sample is raised at a constant rate, the sample reacts and generates heat. The calorific value is output to a chart, and a heating curve and an area surrounded by the base line are obtained based on the base line, and this is defined as a calorific value. The temperature is measured from room temperature to 250 ° C. at a rate of temperature increase of 5 to 10 ° C./min, and the above-mentioned calorific value is obtained. Some of these are performed automatically, and can be easily performed by using them.
Next, the calorific value of the adhesive layer obtained by applying the composition on a heat spreader and drying by heating is determined as follows.

First, the total calorific value of the uncured sample obtained by drying and removing the solvent from the varnish using a vacuum dryer at 25 ° C. is measured, and this is defined as A (J / g) (total curing calorific value). Next, the calorific value of the adhesive layer sample formed by coating on a heat spreader and drying by heating was measured, and this was measured as B (J / g).
And The degree of curing C (%) of the adhesive layer sample (state in which heat generation has been completed by heating and drying) is given by the following equation 1.

C (%) = (Α−B) × 100 / Α Formula 1 The adhesive used in the present invention has a storage elasticity measured by a dynamic viscoelasticity measuring device when cured to a degree of cure of 100%. Modulus (dynamic storage modulus) is 20 to 2,000 at 25 ° C.
MPa, preferably 3-50 MPa at 260 ° C.
It is preferable that the elastic modulus is as low as a. The storage elastic modulus was measured by applying a tensile load to the cured product cured to a degree of cure of the adhesive of 100%, at a frequency of 10 Hz, and at a temperature increase rate of 5 to 5%.
The measurement is performed in a temperature-dependent measurement mode in which measurement is performed from -50 ° C to 300 ° C at a rate of 10 ° C / minute. An adhesive having a storage elastic modulus at 25 ° C. of the cured product of more than 2,000 MPa has a tendency to crack because the effect of relaxing the stress generated by the difference in the coefficient of thermal expansion between the semiconductor chip and the heat spreader is reduced. . On the other hand, if the cured product has a storage elastic modulus at 25 ° C. of less than 20 MPa, the heat spreader with an adhesive may be difficult to handle, or may not be able to maintain the adhesive strength at high temperatures. When the storage elastic modulus at 260 ° C. is less than 3 MPa, a sufficient adhesive strength cannot be maintained. When the storage elastic modulus is more than 50 MPa, the stress generated due to the difference in the thermal expansion coefficient between the semiconductor chip and the heat spreader is reduced. Cracks tend to occur because the effect of relaxation is small.

In the present invention, an epoxy resin-based adhesive containing an epoxy group-containing acrylic copolymer is used as an adhesive for bonding the semiconductor chip and the heat spreader. Low elastic modulus.
Therefore, by increasing the mixing ratio of the epoxy group-containing acrylic copolymer, the cracks due to the effect of relaxing the stress generated in the heating and cooling process during reflow due to the difference in the thermal expansion coefficient between the semiconductor chip and the heat spreader are reduced. And peeling can be suppressed, and a semiconductor device showing excellent reliability can be obtained. In addition, since the epoxy group-containing acrylic copolymer has excellent reactivity with the epoxy resin, the cured adhesive is chemically and physically stable, and exhibits excellent performance in a moisture resistance test represented by PCT processing. . Also, for the following reasons:
In the present invention using the above-mentioned adhesive, the problems when a conventional adhesive film is used are solved, and a semiconductor device having excellent reliability and productivity can be obtained. 1) By using the epoxy group-containing acrylic copolymer specified in the present invention, the occurrence of cracks during reflow can be suppressed. 2) By using an epoxy group-containing acrylic copolymer having a large molecular weight, the strength of the adhesive layer on the heat spreader can be ensured even when the amount of the copolymer is small. 3) By adding a high molecular weight resin compatible with the epoxy resin and having a weight average molecular weight of 30,000 or more,
The tackiness of the adhesive layer can be reduced, and the handleability of the heat spreader with the adhesive is improved.

Further, when an adhesive containing the above-mentioned high molecular weight resin is used as the adhesive, the epoxy resin and the high molecular weight resin have good compatibility and are uniform. Are partially reacted with them, and the whole is crosslinked and gelled, including unreacted epoxy resin. This suppresses the fluidity of the adhesive layer, and even when a large amount of unreacted epoxy resin or the like is contained, the handleability of the heat spreader with the adhesive is not impaired. In addition, since a large number of unreacted epoxy resins remain in the gel, when pressure is applied, unreacted components exude from the gel, so that even if the whole is gelled, the decrease in adhesiveness is reduced. .

When the adhesive varnish is heated and dried, both the epoxy group and the epoxy resin of the epoxy group-containing acrylic copolymer react with each other. However, the epoxy group-containing acrylic copolymer has a large molecular weight and has a large molecular weight in one molecular chain. Contains a large amount of epoxy groups, so that gelation occurs even when the reaction proceeds slightly. Usually, gelation occurs in a state where heat generation of 10 to 40% of the total curing heat generation amount measured by using DSC is completed, that is, in the first half of the A or B stage. Therefore, the gel is formed in a state containing a large amount of unreacted components such as an epoxy resin, and the melt viscosity is significantly increased as compared with a case where the gel is not gelled, so that the handleability is not impaired. In addition, when pressure is applied, unreacted components exude from the gel, and therefore, even when gelled, the adhesiveness is hardly reduced. Furthermore, since the adhesive can be formed into a film with a large amount of unreacted components such as epoxy resin, there is an advantage that the life (effective use period) of the adhesive layer of the heat spreader with the adhesive is increased.

In the conventional epoxy resin-based adhesive, gelation occurs for the first time in the C-stage state from the latter half of the B-stage, and the unreacted components such as the epoxy resin at the stage of the gelation are small, so that the fluidity is low. Even when pressure is applied, the amount of unreacted components oozing out of the gel is small, so that the adhesiveness is reduced.

The epoxy group contained in the epoxy group-containing acrylic copolymer and the low molecular weight epoxy resin (1a)
It is not clear how easily the epoxy groups react, but it is sufficient that they have at least the same degree of reactivity, and only the epoxy groups contained in the epoxy group-containing acrylic copolymer during heating and drying can be selectively used. It need not be responsive.

In this case, the A, B, and C stages are
Indicates the degree of curing of the adhesive. The A stage is in a state of being almost uncured and not gelling, and is a state in which heat generation of 0 to less than 20% of a total curing calorific value measured by using a DSC has been completed. The B stage is in a state in which curing and gelation have progressed slightly, and in a state in which heat generation of less than 20 to 60% of the total curing calorific value has been completed. The C stage is in a state where the curing has progressed considerably and is in a gelled state, and a state where heating of 60 to 100% of the total curing calorific value has been completed.

Regarding the determination of gelation, the adhesive layer was immersed in a highly permeable solvent such as THF (tetrahydrofuran) and allowed to stand at 25 ° C. for 20 hours, after which the adhesive layer was swollen without completely dissolving. Was determined to have gelled. In addition, it experimentally determined as follows.

An adhesive layer (weight W1) is immersed in THF,
After standing at 25 ° C. for 20 hours, the undissolved portion was filtered with a 200-mesh nylon cloth, and the weight after drying was measured (weight W2). The THF extraction rate (%) is calculated by the following equation 2.
It was calculated as follows. Those with a THF extraction rate of more than 80% by weight were not gelled, and those with 80% by weight or less were judged to be gelled.

[0072]

(Equation 1) In the present invention, by adding an inorganic filler to the adhesive, the melt viscosity can be increased, and the thixotropic property can be further exhibited, so that the above effects can be further enhanced.

Further, in addition to the above-mentioned effects, characteristics such as improvement of heat dissipation of the adhesive layer, imparting flame retardancy to the adhesive layer, giving proper viscosity at the temperature at the time of bonding, and improvement of surface hardness are also provided. Can be granted.

The bonding temperature for bonding the heat spreader with the adhesive to the semiconductor chip is usually 30 to 25.
0 ° C, preferably 100 to 180 ° C. If the bonding temperature is lower than 30 ° C., sufficient adhesive strength may not be obtained, and if it is higher than 250 ° C., the heat spreader may be oxidized. Further, the curing of the adhesive layer may proceed too quickly, and the adhesiveness to the semiconductor chip may be impaired. The bonding pressure is usually 0.3 to 5 MPa, preferably 0.5 to 5 MPa, and more preferably 1 to 3 MPa. If the bonding pressure is less than 0.3 MPa, the bonding may be insufficient. If the bonding pressure is more than 5 MPa, the adhesive layer may protrude from a position other than a predetermined position, resulting in poor dimensional accuracy. The pressurizing time is not particularly limited as long as the time can be used for bonding at the bonding temperature and the bonding pressure. However, considering workability, 0.3 to 40 seconds is preferable, 0.3 to 30 seconds is more preferable, and 0.5 to 20 seconds
Seconds are more preferred. After bonding the heat spreader to the semiconductor chip in this manner, a curing treatment of the adhesive layer is performed. The curing temperature of the curing treatment may be a condition under which the degree of cure of the adhesive layer measured by DSC becomes 100%, but is preferably 140 to 190 ° C, more preferably 160 to 180 ° C. The curing time may be a time at which the curing degree of the adhesive layer becomes 100% at the curing temperature, but is preferably 30 minutes to 3 hours, and more preferably 1 to 2 hours.

[0075]

The present invention will be described more specifically with reference to the following examples.

(Example 1) A copper foil having a thickness of 105 μm was used as a heat spreader, and the surface to which the adhesive was applied was subjected to a general oxidation treatment as a surface treatment for an inner layer circuit of a wiring board, followed by a reduction treatment. did.

As an epoxy resin, a bisphenol A type epoxy resin (epoxy equivalent: 200, trade name: Epicoat 828 manufactured by Yuka Shell Epoxy Co., Ltd.) is used.
5 parts by weight, cresol novolak type epoxy resin (epoxy equivalent 220, trade name ES manufactured by Sumitomo Chemical Co., Ltd.)
15 parts by weight of CN001), 40 parts by weight of a phenol novolak resin (trade name: LF2882 manufactured by Dainippon Ink and Chemicals, Inc., weight average molecular weight: 1,300) as a curing agent for the epoxy resin, compatible with the epoxy resin And a phenoxy resin (weight average molecular weight of 50,0) having a weight average molecular weight of 30,000 or more.
00, product name Phenotote YP- manufactured by Toto Kasei Co., Ltd.
50) 15 parts by weight, epoxy group-containing acrylic rubber as epoxy group-containing acrylic copolymer (weight average molecular weight 1,000,000, trade name HTR-860P-3 manufactured by Teikoku Chemical Industry Co., Ltd.) 150 Parts by weight, 1-cyanoethyl-2-phenylimidazole (Curesol 2 (trade name, manufactured by Shikoku Chemicals Co., Ltd.) as a curing accelerator
(PZ-CN) To a composition consisting of 0.5 parts by weight, methyl ethyl ketone was added, mixed with stirring, and degassed under vacuum. The obtained varnish was applied on the heat spreader,
Heat drying at 5 ° C. for 5 minutes to form a coating film (adhesive layer) in a B-stage state having a film thickness of 50 μm, thereby producing a heat spreader with an adhesive.

The degree of cure of the adhesive layer in this state is D
As a result of measurement (heating rate, 10 ° C./min) using SC (trade name: 912 type DSC manufactured by DuPont), it was in a state where heat generation of 15% of the total curing heat generation of the adhesive was completed. Also,
The adhesive layer (weight W1) is immersed in THF,
After standing for a period of time, the undissolved matter was filtered through a 200-mesh nylon cloth, and the weight after drying was measured (weight W
2) The THF extraction rate (= (W1-W2) × 100 / W
When 1) was obtained, the THF extraction ratio was 35% by weight. Further, the storage elastic modulus of a cured product having a curing degree of 100% of the adhesive is measured by a dynamic viscoelasticity measuring device (trade name, manufactured by Rheology Co., DVE-
V4) (sample size 20 mm length,
Width 4 mm, film thickness 50 μm, heating rate 5 ° C./min, tensile mode automatic static load), and as a result,
a, 4 MPa at 260 ° C.

The semiconductor device is a flexible printed wiring board using a polyimide film having a thickness of 25 μm as a base material as an interposer, and a CSP of 12 mm square in which this is integrated with a semiconductor chip is used. It was produced by bonding a heat spreader. The bonding conditions were 150 ° C and 0.5MPa.
The thermocompression bonding was performed for 0 second. This was post-cured in a dryer at 170 ° C. for 60 minutes.

Example 2 Instead of the copper foil used as the heat spreader in Example 1, the surface of the aluminum foil having a thickness of 150 μm to which the adhesive was applied was polished with a # 600 brush and cleaned. γ-glycidoxypropyltrimethoxysilane (NUC manufactured by Nippon Unicar Co., Ltd.)
A-187) was prepared in the same manner as in Example 1 except that the surface was treated with a methyl ethyl ketone solution (using A-187). Next, a semiconductor device was manufactured in the same manner as in Example 1 using this heat spreader with an adhesive.

Example 3 The phenoxy resin used in Example 1 was changed to a carboxyl group-containing acrylonitrile butadiene rubber (weight average molecular weight 400,000, using PNR-1 manufactured by Nippon Synthetic Rubber Co., Ltd.). Except for the above, a heat spreader with an adhesive was produced in the same manner as in Example 1. The degree of curing of the adhesive layer in this state was measured using a DSC, and as a result, heat generation of 20% of the total curing calorific value of the adhesive was completed. Adhesive layer T
The HF extraction rate was 35% by weight. Further, as a result of measuring the storage elastic modulus of the cured product having a curing degree of the adhesive of 100% using a dynamic viscoelasticity measuring device, it was found that the pressure was 300 MPa at 26 ° C.
It was 3 MPa at 0 ° C. Next, a semiconductor device was manufactured in the same manner as in Example 1 using this heat spreader with an adhesive.

Example 4 The same procedure as in Example 1 was repeated except that 10 parts by volume of alumina was added to 100 parts by weight of the solid content of the adhesive of the adhesive varnish of Example 1 and kneaded with a bead mill for 60 minutes. To prepare a heat spreader with an adhesive. The degree of cure of the adhesive layer in this state is DS
As a result of measurement using C, the total curing heat value of the adhesive was 15%.
% Exotherm. The THF extraction rate of the adhesive layer was 30% by weight. Further, the curing degree of the adhesive is 10
As a result of measuring the storage elastic modulus of the cured product of 0% using a dynamic viscoelasticity measuring apparatus, it was found that the storage elastic modulus at 25 ° C. was 1,800 MPa and 260 ° C.
Was 10 MPa. Next, a semiconductor device was manufactured in the same manner as in Example 1 using this heat spreader with an adhesive.

Example 5 A heat spreader with an adhesive was produced in the same manner as in Example 1 except that the phenoxy resin used in Example 1 was not used. The degree of curing of the adhesive layer in this state was measured using a DSC, and as a result, the state of heat generation of 15% of the total curing calorific value of the adhesive was completed. The THF extraction rate of the adhesive layer was 35% by weight. Further, the storage elastic modulus of the cured product having a curing degree of 100% of the adhesive was measured by using a dynamic viscoelasticity measuring device, and as a result, it was 3 at 25 ° C.
It was 4 MPa at 50 MPa and 260 ° C. Next, a semiconductor device was manufactured in the same manner as in Example 1 using this heat spreader with an adhesive.

Comparative Example 1 A heat spreader with an adhesive was produced in the same manner as in Example 1 except that the amount of the epoxy group-containing acrylic rubber was changed from 150 parts by weight to 50 parts by weight. The degree of curing of the adhesive layer in this state was measured using a DSC, and as a result, heat generation of 20% of the total curing calorific value of the adhesive was completed. Adhesive layer T
The HF extraction was 40% by weight. Furthermore, as a result of measuring the storage elastic modulus of a cured product having a curing degree of the adhesive of 100% using a dynamic viscoelasticity measuring device, it was found that
It was 5 MPa at 260 ° C. Next, a semiconductor device was manufactured in the same manner as in Example 1 using this heat spreader with an adhesive.

Comparative Example 2 A heat spreader with an adhesive was produced in the same manner as in Example 1 except that the amount of the epoxy group-containing acrylic rubber in Example 1 was changed from 150 parts by weight to 400 parts by weight. The degree of curing of the adhesive layer in this state was measured using a DSC, and as a result, heat generation of 20% of the total curing calorific value of the adhesive was completed. Adhesive layer T
The HF extraction rate was 30% by weight. Furthermore, as a result of measuring the storage elastic modulus of a cured product having a curing degree of the adhesive of 100% using a dynamic viscoelasticity measuring device, it was found that the pressure was 200 MPa at 25 ° C.
It was 1 MPa at 0 ° C. Next, a semiconductor device was manufactured in the same manner as in Example 1 using this heat spreader with an adhesive.

Comparative Example 3 Example 1 was repeated except that 150 parts by weight of the epoxy group-containing acrylic rubber of Example 1 was changed to phenoxy resin (165 parts by weight of phenoxy resin).
In the same manner as in the above, a heat spreader with an adhesive was produced. The degree of curing of the adhesive layer in this state was measured using a DSC, and as a result, heat generation of 20% of the total curing calorific value of the adhesive was completed. The THF extraction rate of the adhesive layer was 90% by weight. Furthermore, as a result of measuring the storage elastic modulus of the cured product having a curing degree of the adhesive of 100% using a dynamic viscoelasticity measuring device, it was 3400 MPa at 25 ° C. and 3 MPa at 260 ° C. Next, a semiconductor device was manufactured in the same manner as in Example 1 using this heat spreader with an adhesive.

The heat resistance and moisture resistance of the semiconductor devices manufactured in Examples 1 to 5 and Comparative Examples 1 to 3 were examined. As a method for evaluating heat resistance, a reflow crack resistance and a temperature cycle test were applied.

The reflow crack resistance of the semiconductor device was evaluated by passing the sample through an IR reflow furnace set at a maximum temperature of the sample surface of 240 ° C. and maintaining this temperature for 20 seconds, and leaving it at room temperature. The cooling was repeated twice to observe the separation between the semiconductor chip and the heat spreader in the sample. Those without peeling were regarded as good, and those with peeling were regarded as bad.

In the temperature cycle test, the sample was subjected to −55 ° C.
Leave it in the atmosphere for 30 minutes, and then
Assuming that the step of leaving for 0 minutes is one cycle, the number of cycles until peeling between the semiconductor chip and the heat spreader was measured in the same manner as in the evaluation of reflow resistance was evaluated. Those less than were judged as defective.

The moisture resistance was evaluated by treating a semiconductor device sample in a pressure cooker tester for 96 hours (P
CT treatment: temperature: 121 ° C., humidity: 100% RH)
This was performed by observing peeling between the semiconductor chip and the heat spreader and discoloration of the adhesive. A sample in which no peeling between the semiconductor chip and the heat spreader and no discoloration of the adhesive were observed was regarded as good, and a sample in which peeling or discoloration was observed was regarded as defective. The results are shown in Table 1.

[0091]

[Table 1] The adhesives used in Examples 1, 2, 3 and 4 all contain an epoxy resin and a curing agent thereof, a high molecular weight resin compatible with the epoxy resin, an epoxy group-containing acrylic copolymer, and a curing accelerator. The adhesive used in Example 5 was an adhesive containing both an epoxy resin and its curing agent, an epoxy group-containing acrylic copolymer, and a curing accelerator. It is an adhesive exhibiting storage elastic modulus at ℃ and 260 ℃. Therefore, the semiconductor device of the embodiment in which the semiconductor chip is bonded to the heat spreader specified by the present invention using the adhesive applied to the heat spreader has good reflow resistance, temperature cycle test, and PST resistance. Met.

The adhesive used in Comparative Example 1 has a small storage amount of the epoxy group-containing acrylic copolymer in the adhesive specified in the present invention, and therefore has a high storage modulus and cannot reduce stress. Therefore, the semiconductor device of Comparative Example 1 has reflow resistance,
Poor reliability due to poor results in temperature cycle test. Also,
The adhesive used in Comparative Example 2 has a low storage elastic modulus and is good because the amount of the epoxy group-containing acrylic copolymer in the adhesive specified in the present invention is too large. D Handling is poor. Since the adhesive used in Comparative Example 3 does not contain the epoxy group-containing acrylic copolymer specified in the present invention, the adhesive has a high storage modulus and, as in Comparative Example 1, cannot relax stress. Therefore, the semiconductor device of Comparative Example 3 has poor reflow resistance and poor results in the temperature cycle test.

[0093]

As described above, a semiconductor device in which a semiconductor chip and a heat spreader are bonded using the heat spreader with an adhesive of the present invention has a low elastic modulus near the room temperature of the adhesive. Thermal stress during heating and cooling caused by a difference in thermal expansion coefficient between the chip and the heat spreader can be reduced. Therefore, peeling between the semiconductor chip and the heat spreader at the time of reflow is not observed, and the heat resistance is excellent. In addition, it contains an epoxy group-containing acrylic copolymer as a low elastic modulus component, and has less moisture degradation, especially when subjected to a moisture resistance test under severe conditions such as PCT treatment. An excellent semiconductor device can be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of one embodiment of a semiconductor device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate with wiring 2 Semiconductor chip 3 Adhesive 4 Inner lead 5 Heat spreader with adhesive 6 Sealing material 7 External terminal (solder ball)

Continued on the front page (72) Inventor Kazunori Yamamoto 1500 Ogawa Oji, Shimodate City, Ibaraki Pref.Hitachi Chemical Industry Co., Ltd.

Claims (12)

[Claims] 1. A semiconductor device of a chip size package having a heat spreader for improving heat dissipation, wherein a semiconductor chip and a heat spreader are bonded using a heat spreader to which an adhesive is applied in advance. The adhesive is (1) a total of 100 parts by weight of an epoxy resin (1a) having a weight average molecular weight of less than 5,000 and a curing agent (1b) thereof;
1-5 parts by weight and (3) 2-6% by weight of copolymerized units derived from glycidyl (meth) acrylate having a glass transition temperature of -10 ° C or higher and a weight average molecular weight of 60
A semiconductor device comprising 100 to 300 parts by weight of an epoxy group-containing acrylic copolymer having a molecular weight of 000 or more. 2. The semiconductor device according to claim 1, wherein the curing agent (1b) is a phenol resin. 3. The adhesive further comprises: (1) an epoxy resin (1a) having a weight average molecular weight of less than 5,000 and a curing agent (1b) having a total amount of 100 parts by weight; 3) compatible with 1a) and having a weight average molecular weight of 3
2. The semiconductor device according to claim 1, wherein the semiconductor device contains 10 to 40 parts by weight of a high molecular weight resin having a molecular weight of 000 or more. 4. The semiconductor according to claim 3, wherein the curing agent (1b) is a phenol resin, and the high molecular weight resin having a weight average molecular weight of 30,000 or more, which is compatible with the epoxy resin (1a), is a phenoxy resin. apparatus. 5. A heat spreader to which an adhesive has been applied beforehand forms an adhesive layer on the heat spreader by applying a varnish obtained by dissolving the adhesive in a solvent to the heat spreader and removing the solvent by heating. A heat spreader with an adhesive obtained by the above method.
The semiconductor device according to any one of the above. 6. The state in which the adhesive forming the adhesive layer on the heat spreader with the adhesive has finished generating 10 to 40% of the total curing heat generation of the adhesive as measured by DSC. 6. The semiconductor device according to claim 5, wherein 7. The storage elastic modulus when the adhesive is cured to a state where heat generation of 100% of the total curing calorific value when measured using DSC has been completed, and measured using a dynamic viscoelasticity measuring device. Is 20 to 2,000 MPa at 25 ° C., and 26
The semiconductor device according to claim 1, wherein the semiconductor device has a pressure of 3 to 50 MPa at 0 ° C. 8. 8. The semiconductor device according to claim 1, wherein the adhesive contains 2 to 20% by volume of an inorganic filler. 9. The semiconductor device according to claim 8, wherein the inorganic filler is selected from the group consisting of alumina, silica, silicon carbide, boron nitride, and aluminum nitride. 10. The heat spreader is made of aluminum,
The semiconductor device according to claim 1, wherein the semiconductor device is formed of a metal selected from the group consisting of copper, an aluminum alloy, and a copper alloy. 11. The semiconductor device according to claim 1, wherein at least a portion of the heat spreader to which the adhesive is applied is subjected to a surface treatment with a coupling agent. 12. The heat spreader according to claim 1, wherein the heat spreader is formed of copper or a copper alloy, and at least a portion of the heat spreader to which the adhesive is applied is subjected to a blackening treatment. Semiconductor device.